Japan Medical Association Acta Medica Okayama 2433-3298 9 1 2026 Relationship between Maternal Body Composition during Pregnancy and Newborn Birth Weight in Japan 189 197 EN Eriko Eto Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Masakazu Kato Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Satoe Kirino Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Chiaki Kuriyama Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Shujiro Sakata Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Hikari Nakato Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Sakurako Mishima Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Akiko Ohira Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Hisashi Masuyama Department of Obstetrics and Gynecology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Introduction: This study aimed to investigate the changes in maternal body composition during pregnancy in Japanese women and the relationship between maternal body composition and newborn birth weight using pre-pregnancy body mass index (BMI) in all trimesters.<br> Methods: A total of 1,851 pregnant Japanese women were enrolled in this study. Body composition was measured using TANITA MC-190EM. The associations between newborn birth weight and maternal BMI, fat mass (FM), fat-free mass (FFM), total body water (TBW), muscle mass (MM), FM gain, FFM gain, and weight gain were evaluated.<br> Results: The participants’ age and pre-pregnancy BMI were 34.1 years and 21.4 kg/m2, respectively. Among the patients, 13.4%, 73.0%, 10.3%, and 3.3% were underweight, average weight, overweight, and obese, respectively. The FM showed no significant change from the second to third trimesters in the underweight, overweight, and obese groups. Moreover, the FM in the overweight and obese groups did not change during any period. The FFM, TBW, and MM significantly increased from the first to second and second to third trimesters. In BMI-stratified multivariate regression analyses, FFM in the normal and overweight groups was positively associated with birth weight, whereas FM gain was negatively associated in the underweight and normal groups. No significant associations were observed in the obese group.<br> Conclusions: Changes in maternal body composition during pregnancy in Japanese women varied by pre-pregnancy BMI. Associations with birth weight also differed by BMI group. Further prospective studies are needed to confirm these relationships and investigate the mechanisms. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2073-4360 18 7 2026 Effect of Universal Adhesives on Resin Cement–Fiber Post–Core Materials 810 EN Masao Irie Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masahiro Okada Department of Dental Biomaterials, Graduate School of Dentistry, Tohoku University Yukinori Maruo Department of Prosthodontics, Okayama University Kenraro Akiyama Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kumiko Yoshihara Health Research Institute, National Institute of Advanced Industrial Science and Technology Akimasa Tsujimoto Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University Takuya Matsumoto Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University This study evaluated eleven resin cements used as core build-up materials by examining the following properties: (a) push-out force between root dentin and the fiber post; (b) pull-out force between the fiber post and the core build-up material; (c) shear bond strength of the resin cement to root dentin; (d) flexural strength of the resin cement; and (e) flexural modulus of elasticity of the resin cement. The purpose of this investigation was to clarify the relationships between recently available universal adhesives, core build-up materials, resin cements, and fiber posts. All experiments were performed at two evaluation periods: after 1 day of water storage (Base) and after 20,000 thermocycles (TC 20k). For the push-out test, simulated post spaces were prepared in single-rooted human premolars. The specimens were sectioned perpendicular to the long axis into 2 mm-thick slices and then subjected to push-out testing to assess the bond strength of the dentin–resin cement–fiber post complex. No significant differences in bonding performance were found between Base and TC 20k. These findings suggest that universal adhesives used for pretreatment of multiple substrates in fiber post cementation can provide not only strong but also durable adhesion over time. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0971-5894 2026 Suppression of salt-enhanced apoplastic flow by salicylic acid in rice EN Md. Asadulla Al Galib Graduate School of Environmental and Life Science, Okayama University Maoxiang Zhao Graduate School of Environmental and Life Science, Okayama University Toshiyuki Nakamura Graduate School of Environmental and Life Science, Okayama University Yoshimasa Nakamura Graduate School of Environmental and Life Science, Okayama University Yoshihiko Hirai Graduate School of Environmental and Life Science, Okayama University Yoshitaka Nakashima Graduate School of Environmental and Life Science, Okayama University Shintaro Munemasa Graduate School of Environmental and Life Science, Okayama University Izumi C. Mori Institute of Plant Science and Resources, Okayama University Yoshiyuki Murata Graduate School of Environmental and Life Science, Okayama University Salinity enhances apoplastic flow, resulting in an increment of Na+ uptake and a lower K+/Na+ ratio. Salicylic acid (SA) plays an important role in improving salinity tolerance in plants. The effect of exogenous SA on apoplastic flow in salt-treated rice seedlings was studied using an apoplastic tracer, 8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS) in light. Application of NaCl at 25 mM to the hydroponic solution significantly increased PTS uptake, while 25 mM NaCl did not affect seedling growth. Application of 25 mM NaNO3 increased PTS uptake to the same degree. Salinity significantly increased sodium (Na+) content but had no significant effect on potassium (K+) content, resulting in a lower K+/Na+ ratio. The application of SA at 0.05 mM and 0.1 mM to the hydroponic solution reduced Na-enhanced PTS uptake. Salicylic acid at 0.05 mM and 0.1 mM significantly reduced Na+ content and slightly increased K+ content in the shoots of rice seedlings, resulting in a higher K+/Na+ ratio. However, SA at up to 0.1 mM did not increase SA contents in shoots under salt stress. These results suggest that exogenous SA reduces Na+ uptake by suppressing Na+-enhanced apoplastic flow in rice seedlings. These findings provide insight into modulation of Na+ transport pathways from roots to shoots by SA and may allow us to utilize brackish water for rice cultivation and to improve salt-tolerant rice through suppression of salt-enhanced apoplastic flow by chemicals such as salicylic acid. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2662-4435 7 1 2026 Stability and distribution of dense hydrous magnesium silicates in the mantle transition zone under low water activity conditions 265 EN Yunke Song Key Laboratory of High-temperature and High-pressure Study of the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences Xinzhuan Guo State Key Laboratory of Critical Mineral Research and Exploration, Institute of Geochemistry, Chinese Academy of Sciences Kuan Zhai Key Laboratory of High-temperature and High-pressure Study of the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences Wei Guo State Key Laboratory of Geomicrobiology and Environmental Changes, School of Earth Sciences, China University of Geosciences (Wuhan) Takashi Yoshino Institute for Planetary Materials, Okayama University Water plays a central role in controlling the physical and chemical properties of Earth’s deep interior. It remains uncertain how water is stored in subducting slabs within the mantle transition zone, between depths of about 410 and 660 kilometers, and whether dense hydrous magnesium silicates act as major water carriers to greater depths. Here we report high-pressure and high-temperature laboratory experiments on the Mg-Si-H system at pressures of 16 and 21.5 GPa and a temperature of 1400 K to evaluate hydrous phase stability under transition zone conditions. We find that when bulk water content is below 1.22 wt%, H2O is predominantly incorporated into wadsleyite and ringwoodite rather than forming dense hydrous magnesium silicates. Because estimated water contents in subducted oceanic slabs are typically lower than one weight percent, formation of these silicates is unlikely, suggesting that the mantle transition zone may restrict large scale water transport into the lower mantle. No potential conflict of interest relevant to this article was reported.

岡山大学法学会 Acta Medica Okayama 0386-3050 75 3-4 2026 PFOS・PFOA 等の残留性有機汚染物質による水質汚染に関する一考察 ― 取引上の義務の視点から― 438 410 EN H. Tsuji No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1043-1802 37 3 2026 A Cysteine-Specific Cationization Strategy for Versatile Antibody Production against Intrinsically Disordered Proteins 580 589 EN Ryui Sakaguchi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ai Miyamoto Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Rikako Kutsuma Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takeru Mori Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Daichi Nakashima Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mirei Masui Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tomoko Honjo Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Midori Futami Department of Bioscience, Faculty of Life Science, Okayama University of Science Mariko Morii Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toshiyuki Oshiki Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Junichiro Futami Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Several autoantigens relevant to the immune system, especially those targeted by autoantibodies induced by antitumor responses, tend to be rich in disordered regions and are prone to aggregation. This inherent instability presents significant challenges for the production, purification, and analysis of autoantigens in laboratory settings. Cysteine-specific cationization can effectively solubilize and purify these challenging proteins, allowing the isolation of full-length water-soluble antigens in their denatured state. The purified antigens enable accurate multiplex autoantibody assays using a suspension Luminex bead array platform. However, well-validated positive control antibodies are essential to ensuring precise clinical diagnosis. In this study, we prepared and characterized a panel of control antibodies by immunizing rabbits with cysteine-specific S-cationized antigens. The resulting antibodies predominantly recognized linear epitopes and were highly effective as quality control reagents in autoantibody array assays. Additionally, these antibodies maintained their ability to bind to their native, unmodified intracellular counterparts, highlighting the usefulness of this approach for producing antibodies against intrinsically disordered proteins. Although a modest immune response against the S-cationized modification site was observed, it remained minimal and did not affect the usefulness of the antibodies for assay validation. We propose this versatile cysteine-specific cationization platform for managing unstable proteins rich in disordered regions, supporting antigen production for diagnostics, and antibody development for research and validation purposes. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2470-1343 11 9 2026 Water-Resistant Antibacterial Coatings Using Cetylpyridinium Chloride - Graphene Oxide Composites 14570 14577 EN Keisuke Okubo Department of Periodontics and Endodontics, Field of Medical Development, Okayama University Gen Kano Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masato Komoda Research Institute for Interdisciplinary Science, Okayama University Kazuhiro Omori Department of Pathophysiology - Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Shogo Takashiba Department of Pathophysiology - Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hospital-acquired infections remain a persistent threat in healthcare settings, especially with the increasing number of elderly and immunocompromised patients. In situations where the use of disposable materials is difficult, durable antibacterial surface coatings are essential. In this study, we report the structural characterization of cetylpyridinium chloride-graphene oxide (CPC–GO) hybrid materials and the sustainability of their antibacterial effects, aiming at washable antibacterial coatings for medical applications. Graphene oxide (GO) has a large surface area and numerous functional groups, while cetylpyridinium chloride (CPC) is a quaternary ammonium compound with well-documented antibacterial activity. We hypothesized that the stable incorporation of CPC through the functional groups of GO could improve surface retention and provide long-term antibacterial performance. The structural properties of the CPC–GO composites were characterized by UV–vis spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and atomic force microscopy. These analyses confirmed the formation of a complex through ionic bonds and the maintenance of a planar composite structure. The antibacterial performance of the CPC–GO coatings was examined using representative bacteria. Notably, the CPC–GO coatings maintained their antibacterial activity significantly better than the negative controls even after multiple washings. The excellent surface retention of the CPC–GO composite suggests its potential as a next-generation antibacterial coating for areas where disinfection and sterilization are impossible, such as the interior of complex medical devices. This study suggests a strategy to extend the efficacy of existing antibacterial agents through the application of nanomaterials. Future studies will focus on the controlled release, long-term stability, and biocompatibility of CPC to realize clinical applications. No potential conflict of interest relevant to this article was reported.

Japanese Society for Medical and Biological Engineering Acta Medica Okayama 2187-5219 15 2026 Verification of a Skin Electrical Impedance Model for Evaluating Indicators of Skin Barrier Function of Older Adults 160 164 EN Osamu UEHARA Medical Engineering Laboratory, ALCARE Co., Ltd. Yuya FUNAKI Medical Engineering Laboratory, ALCARE Co., Ltd. Takao NAKAMURA Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Skin barrier function has been quantitatively evaluated through trans-epidermal water loss, which has been difficult to measure in clinical settings owing to environmental factors and the measurement time. The thickness and surface water content of the stratum corneum are important indicators of skin barrier function, and current methods for measuring these two indicators are also difficult to implement in clinical settings. Therefore, we developed a model based on skin electrical impedance to estimate the thickness and water content of the stratum corneum, enabling measurement and estimation of these two indicators in a short time. In this study, we verified this model implemented in a portable skin electrical impedance measurement device for estimating the thickness and surface water content of the stratum corneum of the skin in older adults. Thirty-four older individuals were studied. The measurement electrodes were placed in contact with the forearm skin, and an alternating signal of two frequencies was applied to measure the impedance, from which the thickness and surface water content of the stratum corneum were estimated in approximately 5 s. The correlation coefficients between the estimated and measured thickness and between the estimated and measured surface water content were 0.732 and 0.604, respectively. Furthermore, the root mean square errors of the residuals for the thickness and surface water content were 1.66 µm and 3.50 points, respectively, indicating that the model accurately estimated the thickness and surface water content of the stratum corneum, even in the skin of older adults. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2076-3417 16 5 2026 Concentration-Dependent Synergistic Interfacial Interactions Between Multifunctional Acrylate and Silane Coupling Agents in an Organic–Inorganic Nanohybrid Material 2339 EN Yukinori Maruo Department of Prosthodontics, Okayama University Kumiko Yoshihara Health Research Institute, National Institute of Advanced Industrial Science and Technology Masao Irie Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University Naoki Kodama Department of Prosthodontics, Okayama University Mai Yoshizane Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kentaro Akiyama Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Synergistic effects of a multifunctional acrylate and a long-chain silane coupling agent were investigated in an organic–inorganic nanohybrid material. We tested the bond strength of nanohybrid composites treated with experimental primers containing silane coupling agents—3-methacryloxypropyl trimethoxysilane (γ-MPTS) or 8-methacryloxyoctyl trimethoxysilane (8-MOTS)—with or without multifunctional acrylates—trimethylolpropane triacrylate (A-TMPT) or dipentaerythritol hexaacrylate (A-DPH). Shear bond strength was evaluated after 24 h of water storage at 37 °C. Untreated control and silane-only groups exhibited low shear bond strengths (e.g., control: 2.4 ± 2.0 MPa) and failed exclusively at the adhesive interface. While addition of A-TMPT did not significantly improve bond strength, addition of A-DPH produced significantly higher shear bond strengths. Highest strength was achieved with 30% 8-MOTS and A-DPH (22.4 ± 6.1 MPa), followed by 20% γ-MPTS and A-DPH (19.0 ± 7.0 MPa), and A-DPH groups produced cohesive failures. Regardless of the silane used (γ-MPTS or 8-MOTS), incorporating A-DPH in the primer consistently yielded superior bond strengths, indicating a promising strategy for improved adhesion for such nanohybrid systems. These findings provide new insights into optimizing resin–filler interfacial interactions and may contribute to the development of restorative materials with improved long-term clinical durability. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2688-4526 7 2 2026 Safety and efficacy of Rezūm water vapour energy therapy in BPH patients receiving antithrombotic therapy: A Japanese single‐centre experience e70170 EN Takatoshi Moriwake Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yusuke Tominaga Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Satoshi Katayama Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Haruki Kaku Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ichiro Tsuboi Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kasumi Yoshinaga Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tomoaki Yamanoi Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tatsushi Kawada Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takuya Sadahira Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takehiro Iwata Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shingo Nishimura Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kensuke Bekku Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yasuhiro Katayama Department of Urology, Okamura Isshindo Hospital Motoo Araki Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Objectives: The objective of this study is to evaluate the safety and efficacy of Rezūm water vapour energy therapy (WAVE) in Japanese patients with benign prostatic hyperplasia (BPH) continuing antithrombotic therapy and to validate the Okayama University Modified Clavien-Dindo classification (OU-mCD) for perioperative hematuria.<br> Patients and Methods: We retrospectively analysed 80 consecutive patients who underwent WAVE from August 2023 to July 2024, including 37 (46.2%) continuing antithrombotic therapy perioperatively. Hematuria within 30 days was graded using conventional Clavien-Dindo classification and the OU-mCD, a novel classification focusing on intervention necessity. We assessed clinically significant hematuria (Grade ≥ Ib), catheter-free rate, prostate volume reduction and haemoglobin change.<br> Results: Clinically significant hematuria occurred in 21.6% (8/37) of patients continuing antithrombotic therapy versus 4.7% (2/43) without (p = 0.038). All 10 Grade ≥ Ib cases occurred during hospitalization with the catheter in place and were managed conservatively with continuous bladder irrigation (median 1 day); none required transfusion or surgical reintervention. Only one patient required temporary drug discontinuation. Treatment efficacy did not differ by antithrombotic status: 86.2% achieved PVR < 50 ml with 44% mean prostate volume reduction. Multivariate analysis identified antithrombotic therapy as the sole independent risk factor for Grade ≥ Ib hematuria (OR 5.46, 95% CI 1.06–28.16, p = 0.042).<br> Conclusion: WAVE can be safely performed with continued antithrombotic therapy. Whereas Grade ≥Ib hematuria occurred in 25% of antiplatelet/anticoagulant users (vs. 5% without), 75% had no significant bleeding, and all complications were managed conservatively without transfusion. The OU-mCD provides precise complication stratification. These findings suggest outpatient procedures may be feasible with appropriate patient selection. No potential conflict of interest relevant to this article was reported.

Japan Society of Mechanical Engineers Acta Medica Okayama 2187-9745 12 5 2025 Examining OpenFOAM-based LES analysis in terms of inviscid energy conservation and viscous turbulence decay 25-00095 EN Hiroki SUZUKI Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kento TANAKA Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Toshinori KOUCHI Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The present study examines an OpenFOAM-based LES analysis from the viewpoints of inviscid energy conservation and viscous turbulence decay. The Smagorinsky model is employed as the sub-grid scale (SGS) model, and a two-dimensional periodic analytical solution and a three-dimensional periodic Taylor-Green vortex (TGV) are employed to represent inviscid flows. The analytical relationship for the kinetic energy K, dK/dt = 0, with t as the dimensionless time, is utilized to validate the OpenFOAM results. For the viscous flow case, the TGV flow in a three-dimensional periodic cubic domain is adopted, and its turbulence kinetic energy distribution is compared with that obtained by a spectral method to examine the analysis. The OpenFOAM-based analysis exhibits energy conservation error in flows that should ideally conserve energy. For the two-dimensional flow, this error decreases with increasing grid resolution N. However, in the three-dimensional flow, the error does not improve even with higher N. In the three-dimensional TGV flow, the turbulence kinetic energy predicted by OpenFOAM exhibits a strong agreement with that from the spectral method when a standard constant value of the Smagorinsky model is employed and the mesh is sufficiently refined. Conversely, for a condition of relatively coarse mesh, the decay characteristics of turbulent kinetic energy deviate from those of the spectral method, and a higher constant value of the Smagorinsky model than the default value becomes necessary to reproduce comparable results. These results suggests that even in LES simulations where highly accurate conservation laws are not satisfied, adjusting the model constants so that the predicted values match experimental or numerical reference data can improve the apparent reliability of the turbulent kinetic energy in the decaying turbulence. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0956-7135 183 2026 Monitoring postharvest water loss in eggplants (Solanum melongena L.) using UV-induced fluorescence imaging and multivariate analysis 111902 EN Vincent Rotich Laboratory of Biosensing Engineering, Graduate School of Agriculture, Kyoto University Tianqi Gao Laboratory of Biosensing Engineering, Graduate School of Agriculture, Kyoto University Panintorn Prempree Laboratory of Biosensing Engineering, Graduate School of Agriculture, Kyoto University Takahiro Hayashi Laboratory of Biosensing Engineering, Graduate School of Agriculture, Kyoto University Kazuhiko Namba Faculty of Environmental, Life, Natural Science and Technology, Okayama University Mitsuji Monta Faculty of Environmental, Life, Natural Science and Technology, Okayama University Motomi Nishimoto Technology and Innovation Center, Daikin Industries, Ltd. Naoshi Kondo Laboratory of Biosensing Engineering, Graduate School of Agriculture, Kyoto University Eggplant (Solanum melongena L.) is susceptible to significant postharvest losses primarily due to water loss during storage, which affects market quality by causing texture and glossiness degradation. We investigated whether UV-induced fluorescence imaging and EEM (Excitation-Emission Matrix) fluorescence spectroscopy can non-destructively monitor WL under four storage regimes (10 °C/95 % RH, 20 °C/95 % RH, 20 °C/75 % RH, 10 °C/75 % RH). EEMs exhibited three regions; a 365/420 nm blue emission increased most under warm, low-humidity storage and is consistent with phenolic/lignin-related fluorescence. Side-view fluorescence (FL) images showed progressive blue-white emission and surface textural changes that tracked gravimetric water loss (WL). A PLSR model using combined color and texture features from FL and reflectance (CL) images achieved R2CV = 0.88 (RMSECV = 3.47 %) with only six features. To test a minimal predictor, we fit an Analysis of Covariance (ANCOVA) using Day-1 FL MeanBlue as a covariate and storage category as a factor with Leave One Out Cross-validation (LOOCV); this forecasted cumulative WL with R2LOOCV = 0.92 and MAE = 1.88 %. Importantly, this ANCOVA model using Day-1 blue-band fluorescence as a covariate was predictive only under 20 °C/75 % RH; under the other conditions, its contribution was weak. Linear Discriminant Analysis (LDA) and Support Vector Machine (SVM) models achieved accuracies of 94.4 % and 85.2 %, respectively, in differentiating storage conditions. These results support low-cost FL imaging as a practical tool to monitor WL and storage stress. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0969-0239 32 16 2025 Development of sulfation for cellulose pulp to change its fiber morphology and appearance to transparent in water 9663 9677 EN Ayato Nishimura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tetsuya Uchida Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Cellulose pulp (CP) is composed mainly of cellulose which is one of the most useful and sustainable natural polymers. Cellulose-based materials, such as completely dispersed nanofibers and water-soluble cellulose, are transparent in water. Additionally, chemical modification of CP has been employed as a pretreatment for the preparation of nanofibers and to impart absorption properties derived from anionic functional groups. However, little is known about chemically modified CPs comprising micron-scale fibers that are transparent in water.In this study, we synthesized transparent sulfated cellulose pulp (TSCP) that exhibits good dispersion stability, high transparency in water, and highly swollen fiber structures. The sulfation method involved heating sulfamic acid and urea supported on CP. TSCP synthesized using a sulfamic acid amount relative to CP (Q) of 18.5, a molar ratio of urea to sulfamic acid (R) of 0.80, and a reaction temperature of 140 °C exhibited the highest total light transmittance (94.7%) in water, a degree of polymerization (535), and amount of sulfate groups (1.73 mmol/g). Polarization microscopy confirmed that most TSCP fibers swelled in water along the fiber width direction. The structure of hydrous-state TSCP was further confirmed using low-vacuum scanning electron microscopy. The maximum fiber width of the swollen TSCP reached 122 μm, which was approximately six times than that of CP. The crystallinity was equivalent to that of the original CP with a Cellulose I-type crystalline structure. This transparent, hydrous-state TSCP, comprising predominantly swollen CP fibers, demonstrates potential for applications as a transparent material. No potential conflict of interest relevant to this article was reported.

Frontiers Media SA Acta Medica Okayama 1664-462X 16 2025 Structural analysis of PSI-ACPI and PSII-ACPII supercomplexes from a cryptophyte alga Rhodomonas sp. NIES-2332 1716939 EN Wenyue Zhang Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nozomi Yonehara Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mizuki Ishii Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haowei Jiang Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Romain La Rocca Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Pi-Cheng Tsai Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hongjie Li Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koji Kato Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Fusamichi Akita Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Jian-Ren Shen Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Light energy is converted to chemical energy by two photosystems (PSI and PSII) in complex with their light-harvesting complex proteins (LHCI and LHCII) in photosynthesis. Rhodomonas is a member of cryptophyte alga whose LHCs contain unique chlorophyll a/c proteins (ACPs) and phycobiliproteins. We purified PSI-ACPI and PSII-ACPII supercomplexes from a cryptophyte Rhodomonas sp. NIES-2332 and analyzed their structures at high resolutions of 2.08 Å and 2.17 Å, respectively, using cryo-electron microscopy. These structures are largely similar to those reported previously from two other species of cryptophytes, but exhibited some differences in both the pigment locations and subunit structures. A part of the antenna subunits of both photosystems is shifted compared with the previously reported structures from other species of cryptophytes, suggesting some differences in the energy transfer rates from the antenna to the PSI and PSII cores. Newly identified lipids are found to occupy the interfaces between the antennae and cores, which may be important for assembly and stabilization of the supercomplexes. Water molecules surrounding three iron-sulfur clusters of the PSI core are found in our high-resolution structure, some of which are conserved from cyanobacteria to higher plants but some are different. In addition, our structure of PSII-ACPII lacks the subunits of oxygen-evolving complex as well as the Mn4CaO5 cluster, suggesting that the cells are in the S-growth phase, yet the PSI-ACPI structure showed the binding of PsaQ, suggesting that it is in an L-phase. These results suggest that the S-phase and L-phase can co-exist in the cryptophytic cells. The high-resolution structures of both PSI-ACPIs and PSII-ACPIIs solved in this study provide a more solid structural basis for elucidating the energy transfer and quenching mechanisms in this group of the organisms. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2589-0042 28 9 2025 Extensive urine production in euryhaline red stingray for adaptation to hypoosmotic environments 113274 EN Naotaka Aburatani Atmosphere and Ocean Research Institute, The University of Tokyo Wataru Takagi Atmosphere and Ocean Research Institute, The University of Tokyo Marty Kwok-Shing Wong Atmosphere and Ocean Research Institute, The University of Tokyo Nobuhiro Ogawa Atmosphere and Ocean Research Institute, The University of Tokyo Shigehiro Kuraku Department of Genomics and Evolutionary Biology, National Institute of Genetics Mana Sato Department of Genomics and Evolutionary Biology, National Institute of Genetics Kazuhiro Saito Ushimado Marine Institute, Faculty of Science, Okayama University Waichiro Godo Ushimado Marine Institute, Faculty of Science, Okayama University Tatsuya Sakamoto Ushimado Marine Institute, Faculty of Science, Okayama University Susumu Hyodo Atmosphere and Ocean Research Institute, The University of Tokyo Maintaining water balance is a prerequisite for all organisms. Euryhaline elasmobranchs face the severest water-influx potential in fresh water (FW), as they retain high concentrations of urea even in hypotonic environments. To elucidate how they overcome this osmotic challenge, we assessed urine output in conscious euryhaline red stingrays (Hemitrygon akajei). Following acclimation to 5% diluted seawater, the stingrays increased urinary output by 87-fold—the greatest change observed in vertebrates—partly due to 6.8-fold increase in glomerular filtration rate (GFR). In the nephron, expressions of Aquaporin-1 (Aqp1), Aqp3, and Aqp15 were strongly downregulated in FW, indicating that tubular diuresis bridges the gap between GFR and final urine volume. Meanwhile, FW-acclimation upregulated Aqp1 and Aqp4 in the distinct bundle structure, which promotes urea reabsorption. Euryhaline elasmobranchs resolve the huge osmotic challenge of FW by excreting massive amounts of water and retaining osmolytes including urea through coordinated regulation of GFR and Aqp expressions. No potential conflict of interest relevant to this article was reported.

岡山大学文明動態学研究所 Acta Medica Okayama 2436-8326 5 2026 Generating Sacredness in the Domestic Sphere: Wedding Rituals and the Navarātri Kolu Festival in South India 82 100 EN Mayumi IIZUKA JapanTakasaki University of Commerce 特集：Sacred Objects in Religions (Special Issue: Sacred Objects in Religions) 10.18926/70056 This article examines how domestic sacredness is dynamically generated, negotiated, and undone within South Indian Brahmin households. Based on ethnographic analysis of the wedding first-night ritual and the Navarātri kolu festival, the study shows how ritual doubling—exemplified by the marappācci dolls as symbolic doubles of the bridal couple—and the circulation of miniature utensils link life-cycle rites with annual festivals. The kolu’s stepped display condenses cosmological hierarchies while activating gendered forms of ritual practice, auspiciousness (maṅgalam) and purity (śuddham). Everyday acts such as sweeping threshold, sparkling water, drawing kolam, and lighting lamps function as “religious profane” practices that continually remake the boundaries between the mundane and the sacred. Digital sharing and online kolu competitions further extend domestic sacredness into dispersed social networks. By foregrounding materiality, gender, purity, and the ephemerality of ritual arrangements, the article demonstrates that domestic sacredness is a plural, fragile and continually renewed process of making and unmaking. No potential conflict of interest relevant to this article was reported.

岡山大学文明動態学研究所 Acta Medica Okayama 2436-8326 5 2026 「新羅村落文書」に記された村の比定地 ―西原京所属の村（いわゆるＤ村）の検討― 40 53 EN Nana MURAKAMI Research Institute for the Dynamics of Civilizations, Okayama University 研究ノート (Research note) 10.18926/70053 The Silla Village Register is a fragmentary record from the Unified Silla period that details the economic conditions of villages under the jurisdiction of small capitals (小京) and local counties (郡 / 県). In analyzing this register, it is essential to consider the geographical conditions of the locations; however, the exact locations of the villages have long remained unidentified in previous studies. Therefore, this study builds on the readings proposed by Choi Kyŏng-sŏn ( 최 경 선 ) and examines official histories and geographical texts from the Chosŏn dynasty, as well as topographic maps from the early 20th century. As a result, this paper proposes a concrete candidate for the location of one of the four villages under the jurisdiction of Sŏwŏn-gyŏng (西原京), commonly referred to as Village D. It has been clarified that Village D can be read as " 西原京□椒子村" and it is highly likely to correspond to present-day Chojŏng-ri, Naesu-ŭp, Heungdeok-gu, Cheongju City (清州市清原区内秀邑椒井里). It was also found that Village D’s characteristic of having few rice paddies and a high proportion of upland field cultivation closely matches the actual local geographical conditions, which are characterized by limited water resources. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1862-4065 2026 Does Human Depopulation Reduce Resource Consumption? Evidence from Anthropocene Japan EN Anass Barrahmoune Graduate School of Humanities and Social Sciences, Faculty of Economics, Okayama University Peter Matanle School of East Asian Studies, The University of Sheffield Jiyoung Kim Graduate School of Humanities and Social Sciences, Faculty of Economics, Okayama University Humanity’s deepening strain on Earth systems has sparked widespread discussion of an “Anthropocene crisis,” often attributed to overpopulation. This raises the question: if overpopulation underpins the crisis, does its resolution lie in depopulation? Here, we examine the effects of Japan’s ongoing depopulation on the nexus of population, economy, cropland use, food, water, and energy. We take a systematic Bayesian approach to examine changes in the strength and direction of causality among these variables and explore plausible future pathways under Shared Socioeconomic Pathway (SSP) scenarios. We find that, while depopulation has led to reductions in resource demand, notably for water and energy, impacts on the food system are more complex due to interdependencies with economic and other factors beyond population change. In conclusion, we argue that it will take longer than predicted for depopulation dividends to materialize at a scale that could meaningfully contribute to addressing the crisis, and that proactive efforts to reshape consumption patterns and restructure economic systems, from a model predicated on perpetual growth to one oriented toward sufficiency, are necessary to capitalize on the potential dividends offered by this demographic shift. No potential conflict of interest relevant to this article was reported.

Japanese Society of Tribologists Acta Medica Okayama 1881-2198 20 4 2025 Tribological Properties of Amorphous-SiC-Based Coatings on Al2O3 Substrates in Normal Saline 212 219 EN Tadashi Shiota Faculty of Environmental, Life, Natural Science and Technology, Okayama University Daiki Taniya Graduate School of Natural Science and Technology, Okayama University Kazuma Shimazaki Graduate School of Natural Science and Technology, Okayama University Chiyu Nakano Department of Comprehensive Technical Solutions, Okayama University Yuya Omiya Faculty of Environmental, Life, Natural Science and Technology, Okayama University Masahiro Fujii Faculty of Environmental, Life, Natural Science and Technology, Okayama University Amorphous SiC (a-SiC)-based coatings containing not only Si–C bonds but also C–Si–O, C–C, and Si–O2 bonds were deposited on Al2O3 substrates via pulsed laser deposition. Sliding tests using SiC ceramic balls in normal saline revealed that the coating exhibited a low friction coefficient of 0.05-0.06 at a shorter running-in process than SiC bulk ceramic plates. The specific wear rate of the coating was also lower than that of the SiC plate. Reactive molecular dynamics simulations revealed that the C–Si–O bonds in the coating facilitated the generation of Si–O units, which contained Si–O bonds but no Si-C bonds, through tribochemical reactions with water, resulting in superior tribological properties in normal saline compared to those of SiC plates. These findings demonstrate that a-SiC-based coatings containing C–Si–O bonds are promising as low-friction and low-wear coatings for biomedical implants such as ceramic joint prostheses. No potential conflict of interest relevant to this article was reported.

American Society for Microbiology Acta Medica Okayama 0099-2240 2025 Efficient resuscitation of early-stage viable but non-culturable cells of Vibrio cholerae using treatment with proteolytic enzymes EN Shin-ichi Miyoshi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Mona Ogasawara Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shiho Niwaki Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Rena Sugihara Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Basilua Andre Muzembo Research Institute of Nursing Care for People and Community, University of Hyogo Daisuke Imamura Research Center for Intestinal Health Science, Okayama University Vibrio cholerae, the etiological agent of cholera, is ubiquitous in environmental brackish waters. Exposure to low water temperatures induces the bacterium to enter a viable but non-culturable (VBNC) state. In this study, a stepwise decrease in water temperature to 4°C was found to delay the transition to the non-culturable state compared to an abrupt temperature drop, suggesting that V. cholerae cells partially adapt to low temperatures. V. cholerae VBNC cells maintained at 4°C gradually lost their ability to revert to a culturable state. However, VBNC cells in the early stage of dormancy were efficiently resuscitated following treatment with proteolytic enzymes, including proteinase K. The abundance of culturable V. cholerae cells in brackish estuarine waters was quantified using the most probable number (MPN)–quantitative polymerase chain reaction (qPCR) method. Although culturable cells were undetectable in samples treated with bovine serum albumin, they were estimated at 93 and 1,500 MPN/mL in two water samples collected on different days and pre-incubated with proteinase K. Similarly, the abundance of Vibrio species increased markedly following treatment with this enzyme. Additionally, cells of Vibrio species were enumerated by the plating method using CHROMagar Vibrio plates. Consistent with the results of the MPN–qPCR method, treatment with proteinase K resulted in over a 100-fold increase in colony formation. Collectively, these findings suggest that treatment with proteinase K is effective for resuscitating and quantifying V. cholerae VBNC cells in environmental water samples. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2673-7086 5 4 2025 An Integrated QGIS-Based Evacuation Route Optimization Approach for Disaster Preparedness Against Urban Flood in Japan 74 EN Wenliang Pan Graduate School of Environmental and Life Science, Okayama University Shijun Pan Graduate School of Environmental and Life Science, Okayama University Junko Kaneto Graduate School of Environmental and Life Science, Okayama University Keisuke Yoshida Graduate School of Environmental and Life Science, Okayama University Satoshi Nishiyama Graduate School of Environmental and Life Science, Okayama University Urban inland flooding has become a serious problem in many cities because heavy rain often exceeds the capacity of drainage systems. In Japan, GIS-based evacuation maps are commonly used to support disaster preparedness, but they still have several limitations. In particular, they do not avoid flooded road segments and cannot generate multiple evacuation options at the same time. This study proposes an improved evacuation route method using the free and open-source software QGIS. The method combines flood-depth data with road network processing to remove roads where the predicted water depth is higher than 0.5 m. It also provides several evacuation paths to different shelters at the same time. A case study in Kurashiki City, Okayama Prefecture, demonstrates that about 1.37% of the road network becomes unusable during an inland-flood scenario. Several existing evacuation routes also pass through hazardous areas, but the QGIS-based method avoids these areas in most cases. Since the workflow uses only built-in QGIS functions and does not require programming or plug-ins, it is easy to reproduce and apply in other regions. This study offers a practical and low-cost method to support inland-flood evacuation planning for local governments. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2694-2445 5 6 2025 Electronic Structure of the S1 State Manganese Cluster in Photosystem II Investigated Using Q-Band Selective Hole-Burning 660 671 EN Shinya Kosaki Department of Physics, Graduate School of Science, Nagoya University Naohiko Nakamura Department of Physics, Graduate School of Science, Nagoya University Yoshiki Nakajima Research Institute for Interdisciplinary Science, Advanced Research Field, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Advanced Research Field, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroyuki Mino Department of Physics, Graduate School of Science, Nagoya University The electronic structure of the S1 state of photosystem II (PSII) was investigated using selective hole burning of Q-band pulsed electron paramagnetic resonance. The free induction decay and spin–echo signals of the tyrosine radical YD• in the plant PSII oscillated because of the magnetic dipole–dipole interaction with the S1 state Mn cluster. The initial period was 410 ns (2.44 MHz) and was assigned to the S = 1 spin state. Based on the oscillation analysis, both Mn1 and Mn4 and both Mn2 and Mn3 were assigned as Mn(III) and Mn(IV), respectively, which is consistent with the quantum chemical calculations. The 410 ns period was accounted for in the simplified model using the isotropic spin density distribution ratio [1.6:–1.1:–1.1:1.6] for Mn1–4 ions. This oscillation was identical with that observed in the presence of methanol. The oscillation decreased in PsbP/Q- and PsbO/P/Q-depleted PSII. In Thermosynechococcus vulcanus, two periods, 390 ns (2.56 MHz) and 630 ns (1.59 MHz), were detected, indicating that the cyanobacterial S1 state includes two isomers, S = 1 and S ≥ 2 spins. The S ≥ 2 spin was not detected in PsbO/U/V-depleted PSII without polyethylene glycol. The S ≥ 2 state was consistent with the reported quantum chemical calculation using S = 3. A simplified model accounted for the S = 1 state as the spin density distribution [1.8:–1.3:–1.3:1.8] and for the S ≥ 2 state as the isotropic spin density distribution [−0.5:0.5:0.5:0.5] for Mn1–4 ions. In combination with quantum chemical calculations, the most probable protonated structure is W1 = H2O, W2 = H2O, O4 = O2–, and O5 = O2– for the S1 state. These results demonstrate that the selective hole burning method is a powerful tool to complement X-ray studies to determine the valence and protonation structure of manganese clusters, not only in the S1 state but also in higher S-states and general metal clusters, which would provide important insights into the water oxidation mechanism. No potential conflict of interest relevant to this article was reported.

Spandidos Publications Acta Medica Okayama 2049-9450 23 5 2025 Prolonged exposure to axitinib alters the molecular profile of Caki‑2 renal cell carcinoma cells 101 EN Yuko Nakayama Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Himeji Dokkyo University Aya Ino Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Hyogo Medical University Kazuhiro Yamamoto Department of Integrated Clinical and Basic Pharmaceutical Sciences, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kohji Takara Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Hyogo Medical University Axitinib, an oral second‑generation multitargeted tyrosine kinase inhibitor, is used as a second‑line treatment for metastatic renal cell carcinoma (RCC). However, patients often develop resistance after initial responsiveness, necessitating the elucidation of the underlying resistance mechanisms. Therefore, the present study aimed to investigate the mechanisms underlying axitinib resistance using the Caki‑2 human papillary RCC model cells. Cells tolerating 0.1 µM axitinib were designated as Caki/AX cells. Cell viability was assessed using the water‑soluble tetrazolium salt assay. Notably, the 50% inhibitory concentration (IC50) values of axitinib and sunitinib were significantly higher in Caki/AX cells than those in Caki‑2 cells, indicating 2.83‑ and 1.2‑fold resistance, respectively. By contrast, the IC50 values of sorafenib and erlotinib were decreased in Caki/AX cells. Moreover, Caki/AX cells showed resistance to everolimus, temsirolimus and rapamycin, and decreased sensitivity to vinblastine, vincristine, paclitaxel, doxorubicin and SN‑38 compared with Caki‑2 cells. Notably, etoposide, 5‑fluorouracil, cisplatin and carboplatin sensitivities were comparable in both cell types. Reverse transcription‑quantitative polymerase chain reaction (PCR) analysis revealed that the mRNA levels of the ATP‑binding cassette subfamily B member 1 and subfamily G member 2 were significantly higher in Caki/AX cells than those in Caki‑2 cells. A PCR array related to vascular endothelial growth factor signalling showed that the mRNA levels of FIGF (also known as vascular endothelial growth factor D) and sphingosine kinase 1 were upregulated, whereas those of Rac family small GTPase 2 were downregulated in Caki/AX cells. Overall, these findings suggested that the upregulation of the ATP‑binding cassette subfamily B member 1, FIGF and sphingosine kinase 1 mRNA levels, and downregulation of the Rac family small GTPase 2 mRNA levels may contribute to acquired resistance in Caki/AX cells. No potential conflict of interest relevant to this article was reported.

Ceramic Society of Japan Acta Medica Okayama 1348-6535 134 1 2026 Structural and spectroscopic characterization of keatite (SiO2) 1 4 EN Masami Kanzaki Institute for Planetary Materials, Okayama University Xianyu Xue Institute for Planetary Materials, Okayama University Keatite, a polymorph of silica rare in nature, was synthesized by hydrothermal treatment of silicon and water at 100 MPa and 600 °C. The crystal structure of keatite at 24 °C was refined by the Rietveld method using synchrotron X-ray diffraction data. The obtained structure is consistent with the results of previous studies in which some constraints were imposed during refinements. The 29Si MAS NMR spectrum of keatite shows two peaks at −113.9 and −114.3 ppm, which can be assigned to Si at the Si1 and Si2 sites, respectively. The Raman spectrum of keatite shows a prominent peak at 473 cm−1, which is attributable to the Si–O–Si bending mode of the 5-membered ring. These spectra, reported for the first time, are expected to be valuable for the identification of keatite in synthetic and natural samples. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0009-2541 695 2025 Flash vaporization and migration of iodine in the oceanic plate subduction zone 123031 EN Noriyuki Suzuki Department of Earth and Planetary Sciences, Faculty of Science, Hokkaido University Jun Kameda Institute for Planetary Materials, Okayama University Miki Amo Geology and Geophysics Division, Technology Department, Japan Organization for Metals and Energy Security Crustal fluids in subduction zones, such as subsurface aquifers, submarine seeps, and gas hydrate waters, are often rich in iodine (I2) and methane (CH4). Large-scale aquifers in the Kanto subduction zone, where the Pacific Plate (PAC) and the Philippine Sea Plate (PHS) are subducting, also exhibit high concentrations of I2 and CH4. However, the origin and behavior of I2 in the subduction zone are unclear, and its coexistence with CH4 remains unresolved. To investigate this, we compiled the I2 phase diagram under high-pressure and high-temperature (P–T) conditions to predict its physicochemical properties in the subduction zone. We then applied the P–T paths of subducted PAC and PHS sediments to the I2 phase diagram. Our findings reveal that I2 can exist as a liquid in the young and hot PHS subduction zone. Transient decompressions during earthquake ruptures can cause liquid iodine to flash-vaporize and be expelled from subducted sediments. Along with I2, thermogenic CH4 and hydrogen (H2) generated in the subducted sediments are also released and transported upward, likely by slab-dehydrated fluids. Additionally, H2 may enhance microbial CH4 production through hydrogenotrophic methanogenesis. In subduction zones of young and hot oceanic plates such as the PHS, crustal fluids are enriched in I2 and coexist with CH4 owing to the simultaneous expulsion of I2, CH4, and H2 from the same subducted sediments and their migration via deep fluids. Large subsurface aquifers can act as traps and reservoirs for migrating I2 and CH4, forming large-scale I2 and CH4 deposits. No potential conflict of interest relevant to this article was reported.

Iron and Steel Institute of Japan Acta Medica Okayama 0915-1559 65 13 2025 Heat Transfer Enhancement by Forming Bridges among Reactive Particles in a Packed Bed Reactor of a Solid-gas Chemical Heat Storage System 2097 2104 EN Koichi Nakaso Faculty of Environmental, Life Natural Science and Technology, Okayama University Kenji Shimada Graduate School of Natural Science and Technology, Okayama University Yasushi Mino Faculty of Environmental, Life Natural Science and Technology, Okayama University Kuniaki Gotoh Faculty of Environmental, Life Natural Science and Technology, Okayama University In this study, the enhancement of the thermal output of solid-gas chemical heat storage systems was investigated. Bridges made of high-thermal conductivity materials were formed among reactive particles by drying a slurry which contained graphite powder as a thermal additive and dispersant in a packed-bed reactor. First, the effect of the volume ratio of the dispersant on effective thermal conductivity was investigated. The optimum volume ratio of dispersant to graphite powder was determined. Furthermore, repetitive bridge formation increased the effective thermal conductivity. Based on these results, we investigated the thermal response of the energy-discharge process. Consequently, the temperature distribution in the radial direction of the reactor decreased owing to the formation of bridges. In addition, the thermal energy generated by the adsorption of water vapor onto the adsorbent was effectively transferred to the reactor wall. The thermal output was estimated based on the experimental results. The thermal output was increased by the formation of bridges. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2772-4271 21 2026 Assessing water resources availability and crop performance under climate change in Kenya's Bura irrigation scheme using SWAT and AquaCrop 100624 EN Daniel Mwendwa Wambua Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University Morihiro Maeda Graduate School of Environmental and Life Science, Okayama University The current study focused on Tana River Basin in Kenya, home to the Bura irrigation scheme (BIS). The BIS faces water supply shortages during critical months of crop development. This study aimed to evaluate the available water resources and crop performance using the Soil and Water Assessment Tool (SWAT) and AquaCrop, respectively, under historical and future shared socioeconomic pathways (SSPs) at the BIS. SWAT estimated the total available flows (TAF) at the BIS intake, whereas AquaCrop estimated crop water requirements (CWR), yields, and water productivity (Wpet) of rice and maize at various carbon (IV) oxide (CO2) levels. The study suggested that the TAF will remain relatively low during the early critical crop development stages in the main cropping season, August-October. Maize yields remained steady over the two cropping seasons under both constant and elevated CO2 levels in the historical and future periods, as opposed to those of rice. Elevated CO2 levels led to diminishing CWR. Moreover, rice showed a stronger response to elevated CO2 than maize. As a result, maize which is less affected by variations in CO2 and temperatures and has less crop water requirements will be better suited than rice for cultivation in the BIS under climate change. To ensure a sustainable water supply in the scheme, the government should increase rainwater harvesting during periods of high TAF. Moreover, there should be a focus on introducing crops that are tolerant to water and temperature stresses and that can reap the most from the elevated CO2 levels. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2452-199X 57 2026 Robust adhesion between solid-state hydroxyapatite and bone tissue through surface demineralization 632 645 EN Shichao Xie Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masahiro Okada Division of Biomaterials Science and Engineering, Graduate School of Dentistry, Tohoku University Haruyuki Aoyagi Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihisa Otaka Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Xiaofeng Yang Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takayoshi Nakano Division of Materials and Manufacturing Science, Graduate School of Engineering, The University of Osaka Takuya Matsumoto Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Objective: Current bone adhesives typically lack adequate mechanical strength, long-term stability, or biocompatibility. To address these limitations, we designed a new adhesion strategy using a solid-state hydroxyapatite (HAp) adhesive in combination with bone surface demineralization.<br> Methods: Solid-state HAp adhesives were synthesized via wet chemical precipitation and heat treatment. Cortical bone specimens were partially demineralized with phosphoric acid (H3PO4) or ethylenediaminetetraacetic acid (EDTA), and characterized using scanning electron microscopy (SEM) and attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR). Shear adhesion strength of HAp to demineralized bone was measured over time. In vivo fixation was assessed in rats using micro-computed tomography and histology. Statistical analysis used Tukey-Kramer tests after normality and variance checks.<br> Results: Although the HAp adhesive failed to adhere to non-demineralized bone, effective adhesion was achieved on the surface-demineralized bone tissue. Shear adhesion strength was significantly higher in EDTA-treated samples (238.4 kPa at 10 h) compared to H3PO4-treated samples (102.9 kPa at 1 h), with performance correlating with demineralization depth. ATR-FTIR and SEM analyses revealed that EDTA preserved collagen's triple-helix structure and free water content, both enhancing adhesion. Animal experiments confirmed stable fixation of HAp adhesive to demineralized bone tissue.<br> Conclusions: Surface demineralization enabled strong adhesion of the solid-state HAp adhesive to bone by exposing collagen swollen with water. Adhesion strength was influenced by structural changes in the demineralized layer, and the adhesive provided stable in vivo fixation, supporting its potential for bone-anchored biomedical applications. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 79 6 2025 Exacerbation of Proteinuria in a Patient with Behçet’s Disease and IgA Nephropathy Following Colchicine Discontinuation 457 461 EN Tomohiko Asakawa Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Haruhito A. Uchida Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Yu Katayama Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Yoshimasa Sakurabu Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Katsuyoshi Katayama Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Yasuhiro Onishi Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Natsumi Matsuoka-Uchiyama Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Hidemi Takeuchi Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Keiko Tanaka Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Kenji Tsuji Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Ryoko Umebayashi Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Rika Takemoto Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Jun Wada Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences Case Report 10.18926/AMO/69849 This case involves a 23-year-old male who was diagnosed with Behçet’s disease 5 years ago and managed with colchicine. Two months ago, he underwent renal biopsy due to abnormal urinalysis and kidney dysfunction, leading to a diagnosis of IgA nephropathy. He subsequently underwent tonsillectomy followed by glucocorticoid pulse therapy. However, after the tonsillectomy, discontinuing colchicine led to increased proteinuria, despite the glucocorticoid pulse therapy. Upon reintroducing colchicine, urinary protein excretion decreased, achieving incomplete remission. These findings suggest that colchicine may be effective in decreasing proteinuria in patients with Behçet’s disease complicated by IgA nephropathy. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 79 6 2025 Frailty at 1 Month before ICU Admission Poses a Hospital Mortality Risk in Cancer Survivors whose Condition Has Deteriorated due to Medical Factors 437 444 EN Junya Matsumi Department of Anesthesiology and Intensive Care Medicine, National Cancer Center Hospital Tetsufumi Sato Department of Anesthesiology and Intensive Care Medicine, National Cancer Center Hospital Original Article 10.18926/AMO/69846 The optimal indications for intensive care unit (ICU) treatment for critically ill cancer survivors whose condition has deteriorated due to medical factors are unclear. To test our hypothesis that frailty before deterioration was associated with hospital mortality in this patient population, we retrospective analyzed the cases of the patients admitted to the ICU at the National Cancer Center Hospital, Japan (April 2014-March 2022). We excluded patients who underwent surgery within 28 days or were denied critical care within 24 h or admitted after cardiopulmonary arrest. Their Clinical Frailty Scale (CFS) scores at 1 month before ICU admission (Pre-ICU) were obtained. Frailty was defined as CFS scores ≥4 points. We analyzed 298 admissions and observed that the mortality rate at hospital discharge was significantly higher in the frailty group (n=119). A multivariate analysis demonstrated that the following factors were significantly associated with hospital mortality: Pre-ICU frailty (OR 2.00, 95%CI: 1.19-3.36, p=0.009), cancer type (hematological: OR 2.93, 95%CI: 1.42-6.05, p=0.004), and Sequential Organ Failure Assessment score at ICU admission (OR 0.88, 95%CI: 0.82-0.95, p=0.0008). Frailty retrospectively assessed using the CFS at 1 month pre-ICU admission is a risk factor for hospital mortality in these cancer survivors. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2772-5022 5 2 2025 Amelioration of Cd-induced bone deterioration by orally administered calcium phosphate 101482 EN Ping-chin Sung Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ahmad Bikharudin Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masahiro Okada Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Randa Musa Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kenta Uchida Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihisa Otaka Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadaaki Matsusaka Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University Aira Matsugaki Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University Takayoshi Nakano Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University Takuya Matsumoto Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Cadmium (Cd) is a heavy metal that accumulates in the body, primarily through daily grain intake, and has a high affinity for bone, leading to skeletal diseases such as osteomalacia and fractures. Hydroxyapatite (HAp), a major bone mineral component, is highly pH-sensitive and is known to incorporate Cd, as observed in studies of Itai-itai disease. Based on these findings, we hypothesized that HAp could serve as an effective oral detoxification material for heavy metals. This study investigated the efficacy of orally administered HAp in inhibiting Cd-induced changes in bone physical and chemical properties, comparing its effects to those of activated charcoal (AC), a common detoxifying agent. Six-week-old male ICR mice were exposed to cadmium via drinking water containing CdCl2 and subsequently given diets containing either HAp or AC for four weeks. Three-point bending tests, micro-CT analysis, and histological observations of the femurs demonstrated that mice receiving HAp exhibited improved mechanical strength and enhanced bone quality protection compared to the control and other Cd-treated groups. Activated charcoal also contributed to bone quality improvement at low concentrations, but its effect diminished at high concentrations. These results suggest that the oral administration of HAp may be a promising therapeutic strategy for suppressing cadmium-induced osteomalacia. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1120-1797 140 2025 Improvements of lateral penumbra at various depth regions in proton pencil beam scanning with a multileaf collimator: Dose verifications and plan comparisons 105684 EN Yuki Tominaga Department of Radiotherapy, Medical Co. Hakuhokai, Osaka Proton Therapy Clinic Yushi Wakisaka Department of Radiotherapy, Medical Co. Hakuhokai, Osaka Proton Therapy Clinic Takahiro Kato Department of Radiological Sciences, School of Health Sciences, Fukushima Medical University Keisuke Yasui School of Medical Sciences, Fujita Health University Ryohei Kato Department of Radiation Physics and Technology, Southern Tohoku Proton Therapy Center Masaya Ichihara Medical Physics Laboratory, Division of Health Science, Graduate School of Medicine, The University of Osaka Masashi Tomida Department of Proton Beam Technology Room, Narita Memorial Proton Center Motoharu Sasaki Graduate School of Biomedical Sciences, Tokushima University Masataka Oita Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Teiji Nishio Medical Physics Laboratory, Division of Health Science, Graduate School of Medicine, The University of Osaka Purpose: In scanned proton therapy, the current consensus is that the effective range of the collimator’s contribution to lateral penumbra improvement is up to approximately 150 mm depth. We characterized the penumbra variations for scanned proton beams with or without a new type of multileaf collimator (MLC) under various air gaps, depth, and with or without range shifter (RS).<br> Methods: Eighty-six uniform dose plans were created (38 RS-negative and 48 RS-positive plans) for nine box targets of 60 × 60 × 54 mm3 at 0–280 mm depths in water. They were created with or without MLC, with 50–300 mm air gaps. The penumbra and average doses of MLC-positive and MLC-negative plans at the organs at risk (OAR) region of each box plan were compared. Besides, several plan doses were validated by measurements with penumbra (with an average of 80–20 % dose point widths for both side profiles) differences and 2D gamma analysis.<br> Results: The MLC-positive plans reduced the penumbra and mean OAR doses by 1.0–5.1 mm and 3.3–13.5 %, respectively, compared to MLC-negative plans even at >150 mm depths. The penumbra differences in measurements were <±1.5 mm for all plans. The mean gamma scores at 2 %/2 mm were 97.9 ± 2.3 % and 97.4 ± 3.1 % for the MLC-negative and MLC-positive plans, respectively.<br> Conclusions: The MLC-positive beams improved the penumbra and reduced the OAR dose in every depth region and air gap. We have shown that PBS with MLCs can be useful at more than 150 mm regions, depending on the machine. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2155-5435 15 14 2025 Mesoporous Oxyhalide Aggregates Exhibiting Improved Photocatalytic Activity for Visible-Light H2 Evolution and CO2 Reduction 12551 12562 EN Hiroto Ueki Department of Chemistry, School of Science, Institute of Science Tokyo Toshiya Tanaka Department of Chemistry, School of Science, Institute of Science Tokyo Shuji Anabuki Graduate School of Natural Science and Technology, Okayama University Ryuichi Nakada Department of Chemistry, School of Science, Institute of Science Tokyo Megumi Okazaki Department of Chemistry, School of Science, Institute of Science Tokyo Kenta Aihara Department of Chemistry, School of Science, Institute of Science Tokyo Masashi Hattori Materials and Structures Laboratory, Institute of Integrated Research, Institute of Science Tokyo Fumitaka Ishiwari Department of Applied Chemistry, Graduate School of Engineering, Osaka University Rie Haruki Institute of Materials Structure Science, High Energy Accelerator Research Organization Shunsuke Nozawa Institute of Materials Structure Science, High Energy Accelerator Research Organization Toshiyuki Yokoi Nanospace Catalysis Unit, Institute of Integrated Research, Institute of Science Tokyo Michikazu Hara Materials and Structures Laboratory, Institute of Integrated Research, Institute of Science Tokyo Osamu Ishitani Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University Akinori Saeki Department of Applied Chemistry, Graduate School of Engineering, Osaka University Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Kazuhiko Maeda Department of Chemistry, School of Science, Institute of Science Tokyo Oxyhalides are promising visible-light photocatalysts for water splitting and CO2 conversion; however, those exhibiting high activity for these reactions have rarely been reported. Here, we show that using water-soluble Ti complexes as precursors in the microwave-assisted hydrothermal synthesis of the oxyhalide photocatalyst Pb2Ti2O5.4F1.2 (PTOF) resulted in the production of nanoparticulate PTOF. The primary particle size of the synthesized PTOF ranged from several tens of nanometers to several hundreds of nanometers. Using Ti-citric acid or Ti-tartaric acid complexes as precursors, the PTOF was formed as mesoporous aggregates, compared with a bulky analogue (0.5–1 μm) prepared using a TiCl4 precursor. The PTOF prepared from Ti-citric acid complex had a particle size of 50–100 nm and showed a one-order-of-magnitude greater activity for H2 evolution from an aqueous ethylenediaminetetraacetic acid solution with the aid of a Rh cocatalyst. An apparent quantum yield (AQY) of 15.4 ± 1.0% at 420 nm, which is the highest among the reported oxyhalide photocatalysts, was achieved under optimal conditions. Although excess particle size reduction of PTOF lowered the H2 evolution activity, the PTOF with the smallest possible primary particle size of 15–30 nm, prepared from Ti-tartaric acid complex, showed the highest activity toward the selective reduction of CO2 into formate in a nonaqueous environment when combined with a binuclear Ru(II) complex. The CO2 reduction AQY was 10.4 ± 1.8% at 420 nm, a record-high value among metal-complex/semiconductor binary hybrid photocatalysts. This study highlights the importance of morphological control of oxyhalides for realizing their full potential as photocatalysts for artificial photosynthesis. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0361-5995 89 3 2025 Autoclaved lightweight aerated concrete suppressed N2O and CO2 emissions from paddy soil e70091 EN Nagoda R. R. W. S. Rathnayake Department of Soil Science, Faculty of Agriculture, University of Ruhuna Morihiro Maeda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Dewpura A. L. Leelamanie Department of Soil Science, Faculty of Agriculture, University of Ruhuna Atsushi Yatagai Clion Co. Ltd Autoclaved lightweight aerated concrete (AAC), a construction waste that is utilized as a soil amendment, can influence terrestrial carbon dioxide (CO2) emissions. Still, no evidence exists regarding its impact on the emission of nitrous oxide (N2O), which has a higher global warming potential. This study examined effects of AAC on CO2 and N2O emissions from paddy soil under compacted and non-compacted conditions, under 60% and 100% water-holding capacity (WHC). Samples were incubated in glass vials (25°C) for 21 days. Emissions of CO2 and N2O were measured on days 0, 1, 3, 7, 14, and 21 using gas chromatography. The results revealed that AAC significantly (p < 0.05) lowered N2O emission rate during the whole period of incubation, while it suppressed CO2 emission rate only at the early stages (∼7 days) of incubation. In compacted soil, the emissions of CO2 were significantly lower, while N2O was significantly higher than that in non-compacted soil, showing the influence of soil physical conditions. The emissions of CO2 and N2O were significantly lower at 100% WHC than those at 60% WHC. AAC suppressed both CO2 and N2O emissions under both compaction and WHC levels. The results confirm that AAC supports suppressing terrestrial emission of both CO2 and N2O, indicating that AAC has a potential as a sustainable soil amendment that enhances the climate change resilience. No potential conflict of interest relevant to this article was reported.

Biophysical Society of Japan Acta Medica Okayama 2189-4779 22 3 2025 Origin of the unique topology of the triangular water cluster in &lt;i&gt;Rubrobacter xylanophilus&lt;/i&gt; rhodopsin e220018 EN Tomoyasu Noji Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo Masaki Tsujimura Department of Advanced Interdisciplinary Studies, The University of Tokyo Keisuke Saito Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo Keiichi Kojima Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuki Sudo Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hiroshi Ishikita Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo The crystal structure of Rubrobacter xylanophilus rhodopsin (RxR) reveals a triangular cluster of three water molecules (W413, W415, and W419) at the extracellular proton-release site, near Glu187 and Glu197. Using a quantum mechanical/molecular mechanical approach, we identified the structural nature of this unique water cluster. The triangular shape is best reproduced when all three water molecules are neutral H2O with protonated Glu187 and deprotonated Glu197. Attempts to place H3O+ at any of these water molecules result in spontaneous proton transfer to one of the acidic residues and significant distortion from the crystal structure. The plane defined by the triangular water cluster extends into the guanidinium plane of Arg71, with both aligned along the W413...W419 axis. This extended plane lies nearly perpendicular to a five-membered, ring-like H-bond network involving two carboxyl oxygen atoms from Glu187 and one from Glu197. The resulting bipartite planar architecture, defined by the water triangle, Arg71, and the Glu187/Glu197 network may reflect the exceptional thermal stability in RxR. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0883-2927 187 2025 Nitrogen distribution and nitrogen isotope fractionation in synthetic 2:1 phyllosilicates under hydrothermal conditions at 200 °C and saturated vapor pressure 106403 EN Jaeguk Jo Graduate School of Natural Science and Technology, Okayama University Toshiro Yamanaka Graduate School of Natural Science and Technology, Okayama University Youko Miyoshi Research Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST) Masaya Suzuki Research Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST) Yoshihiro Kuwahara Department of Environmental Changes, Faculty of Social and Cultural Studies, Kyushu University Isao Kadota Graduate School of Natural Science and Technology, Okayama University Hitoshi Chiba Graduate School of Natural Science and Technology, Okayama University Bum Han Lee Critical Minerals Research Center, Korea Institute of Geoscience & Mineral Resources (KIGAM) This study investigates nitrogen distribution and isotope fractionation within synthetic 2:1 phyllosilicates, simulating submarine hydrothermal environments at 200 °C and saturated vapor pressure. XRD and EDS results revealed the potential coexistence of multiple cations in the interlayer of synthetic 2:1 phyllosilicate, concurrently suggesting cation substitution in the tetrahedral and/or octahedral sheets. Meanwhile, the iron-enriched 25-5 sample exhibited restricted interlayer expansibility. NH4+ absorptions were identified in the NH4-stretching (3200–2800 cm−1) and NH4-bending (1450–1400 cm−1) regions, with wavenumber shifts indicating the influence of interlayer water removal. At pH 10.56, over 95% of nitrogen was released into the gas phase, while at pH 8.88, nitrogen proportions in the liquid and gas phases were comparable (average 48–49%). Experiments with iron at pH ∼8.80 showed that the nitrogen proportion in the gas phase (average 28%) was more than twofold lower than that in the liquid phase (average 68%). Equilibrium isotope fractionation factors indicated discernible preference for heavier nitrogen isotopes in the solid phase (αsolid-liquid = 1.009–1.021 and αsolid-gas = 1.011–1.027). The αliquid-gas range for sample 25–2 was 1.001–1.008, while that for the iron-enriched composite 25–5 was 0.997–1.010. Our experimental studies have confirmed that, in the absence of exchange interactions with external substances possessing different nitrogen isotope ratios, nitrogen isotope fractionation between ammonium and ammonia, controlled by variations in temperature and pH during mineralization, plays a crucial role in the variation of nitrogen isotope ratios. Additionally, we confirmed that metal-amines influence nitrogen isotope fractionation by modulating ammonia gas emission. These findings enhance our understanding of nitrogen cycling across the gas, liquid, and solid phases in submarine hydrothermal systems. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2504-3129 6 4 2025 Drip Fertigation in Greenhouse Eggplant Cultivation: Reducing N2O Emissions and Nitrate Leaching 116 EN Wataru Shiraishi Kochi Prefectural Agricultural Research Center Shion Nishimura Department of Bioresource Production Science, United Graduate School of Agriculture, Ehime University Morihiro Maeda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hideto Ueno Department of Bioresource Production Science, United Graduate School of Agriculture, Ehime University Drip fertigation (DF) is a sustainable agricultural management technique that optimizes water and nutrient usage, enhances crop productivity, and reduces environmental impact. Herein, we compared the effects of DF and conventional fertilization (CF) with a basal fertilizer on yield, soil inorganic nitrogen dynamics, N2O emissions, and nitrogen leaching during facility-grown eggplant cultivation. The experiment was conducted in a greenhouse from September 2023 to May 2024, with treatments arranged in three rows and three replicates. Soil, gas, and water samples were collected and analyzed throughout the growing season. The results revealed that the DF treatment produced yields comparable to those obtained with the CF treatment while significantly reducing nitrogen and phosphorus inputs. DF effectively prevented excessive nitrogen accumulation in the soil and reduced nitrogen loss through leaching and gas emissions. N2O emissions were significantly lower by more than 60% under DF than under CF. Precise nutrient management in DF suppressed nitrification and denitrification processes, mitigating N2O emissions. DF also significantly reduced nitrogen leaching by more than 70% compared with that in CF. These findings demonstrate that DF effectively enhances agricultural sustainability by improving nutrient use efficiency, reducing greenhouse gas emissions, and minimizing nitrogen leaching during the cultivation of facility-grown eggplant. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 16 1 2025 Efficient and stable n-type sulfide overall water splitting with separated hydrogen production 8786 EN Haolin Luo Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Zhixi Liu Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Haifeng Lv State Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Material Sciences, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China Junie Jhon M. Vequizo Institute of Aqua Regeneration, Shinshu University Mengting Zheng College of Chemical and Biological Engineering, Zhejiang University Feng Han Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Zhen Ye Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Akira Yamakata Faculty of Natural Science and Technology, Okayama University Wenfeng Shangguan Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Adam F. Lee Centre for Catalysis and Clean Energy, School of Environment and Science, Griffith University Xiaojun Wu State Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Material Sciences, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China Domen Kazunari Institute of Aqua Regeneration, Shinshu University Jun Lu College of Chemical and Biological Engineering, Zhejiang University Zhi Jiang Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University N-type sulfide semiconductors are promising photocatalysts due to their broad visible-light absorption, facile synthesis and chemical diversity. However, photocorrosion and limited electron transport in one-step excitation and solid-state Z-scheme systems hinder efficient overall water splitting. Liquid-phase Z-schemes offer a viable alternative, but sluggish mediator kinetics and interfacial side reactions impede their construction. Here we report a stable Z-scheme system integrating n-type CdS and BiVO₄ with a [Fe(CN)₆]³⁻/[Fe(CN)₆]⁴⁻ mediator, achieving 10.2% apparent quantum yield at 450 nm with stoichiometric H₂/O₂ evolution. High activity reflects synergies between Pt@CrOx and Co3O4 cocatalysts on CdS, and cobalt-directed facet asymmetry in BiVO₄, resulting in matched kinetics for hydrogen and oxygen evolution in a reversible mediator solution. Stability is dramatically improved through coating CdS and BiVO4 with different oxides to inhibit Fe4[Fe(CN)6]3 precipitation and deactivation by a hitherto unrecognized mechanism. Separate hydrogen and oxygen production is also demonstrated in a two-compartment reactor under visible light and ambient conditions. This work unlocks the long-sought potential of n-type sulfides for efficient, durable and safe solar-driven hydrogen production. No potential conflict of interest relevant to this article was reported.

Ceramic Society of Japan Acta Medica Okayama 1348-6535 133 7 2025 Underwater superoleophobic NaNbO3-based photocatalyst thin films prepared on bare soda-lime glass by sol–gel process 393 399 EN Shunsuke Nishimoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuya Kageyama Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shusuke Egusa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshikazu Kameshima Graduate School of Environmental, Life, Natural Science and Technology, Okayama University A self-cleaning flat transparent thin photocatalyst film was prepared on a bare soda-lime glass by a simple method using niobium alkoxide solution, which is a common coating solution for the sol–gel method. The film consisted of crystalline NaNbO3 and Na2Nb2O6·H2O phases. It was suggested that NaNbO3 and Na2Nb2O6·H2O were directly formed between the soda-lime glass and the niobium alkoxide coating solution during the heat treatment. Under UV irradiation, the film surface exhibited low photocatalytic oxidation activity and excellent photo-induced hydrophilicity. The hydrophilic state of the sample was maintained for 1 month in the dark, while the hydrophilicity of TiO2 sample prepared by a sol–gel method was decreased within 5 days in the dark. Additionally, the surface demonstrated excellent underwater oil repellency toward n-hexadecane and oleic acid and the ability to remove the adsorbed oily contaminant in water. These properties were also superior to those of the TiO2 surface. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1470-160X 177 2025 Long-term effects of forest growth dynamics and climate change on groundwater recharge and evapotranspiration in a steep catchment of western Japan 113652 EN Rendilicha Halake Guyo Graduate School of Environmental and Life Science, Okayama University Kunyang Wang Graduate School of Advanced Science and Engineering, Hiroshima University Shin-ichi Onodera Graduate School of Advanced Science and Engineering, Hiroshima University Mitsuyo Saito Graduate School of Advanced Science and Engineering, Hiroshima University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University Growing water demand for human and environmental needs has led to increased reliance on groundwater resources. However, groundwater is a finite resource, and its sustainability is closely linked to recharge processes, which are influenced by forest growth dynamics as well as climate change. Evapotranspiration, largely driven by vegetation cover and climatic conditions, represents a major component of terrestrial water loss that can reduce groundwater recharge. In this study, forest growth trends, reflecting the complete developmental stages from juvenile to post-maturity of a representative species, were reconstructed using remote sensing data, forest inventories, and field studies, and incorporated into the SWAT model to evaluate their impacts on groundwater recharge and evapotranspiration as indicators of forest hydrological function and ecosystem health. The model’s vegetation growth simulation was enhanced and uncertainty reduced by dynamically updating it with MODIS-derived leaf area index (LAI) at 5-year intervals. Groundwater recharge estimates were further improved through multi-variable calibration using Penman–Monteith–Leuning evapotranspiration (V2) and streamflow data to ensure water budget closure. Results showed that evergreen conifer growth from planting to maturity significantly reduced groundwater recharge (–4.7 mm/year) and increased evapotranspiration (+7.6 mm/year). In contrast, natural and mature deciduous broadleaf forests showed more stable recharge and evapotranspiration trends. Rising temperatures were identified as a key climatic driver of reduced recharge and increased evapotranspiration, reflecting broader global warming impacts. This study demonstrates that forest growth dynamics, especially during the critical transition from planting to maturity, alongside climate change, play a crucial role in shaping the catchment’s water balance and offer valuable insights for sustainable groundwater management, particularly in transitional forest ecosystems. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1350-4487 191 2026 A novel wearable dosimeter system that can analyze the incident direction of X-rays for medical dosimetry – Improvements to the detector arrangements and analysis algorithm – 107592 EN Takashi Asahara Department of Radiological Technology, Faculty of Health Sciences, Okayama University Rina Nishigami Graduate School of Medical Sciences, Kanazawa University Daiki Kobayashi Graduate School of Medical Sciences, Kanazawa University Natsumi Kimoto Department of Radiological Science, Faculty of Health Sciences, Junshin Gakuen University Sota Goto Faculty of Health Science, Kobe Tokiwa University Kazuki Takegami Department of Radiological Technology, Yamaguchi University Hospital Rin Ishii College of Transdisciplinary Sciences for Innovation, Kanazawa University Mana Mitani Division of Radiological Technology, Medical Support Department, Okayama University Hospital Mitsugi Honda Division of Radiological Technology, Medical Support Department, Okayama University Hospital Toshihiro Iguchi Department of Radiological Technology, Faculty of Health Sciences, Okayama University Hiroaki Hayashi College of Transdisciplinary Sciences for Innovation, Kanazawa University When performing real-time dosimetry using an active-type dosimeter during clinical fluoroscopic procedures, angular dependence of dosimeter response should be taken into account. Our research group addressed this issue and proposed a triple-type dosimeter that can determine the incident angle of scattered X-rays. The triple-type detector consists of three active dosimeters. The two side dosimeters have slope filters to enhance the angular dependence and are intentionally tilted. The central dosimeter faces forward. The incident angle of X-rays (θin) is estimated using the signal differences between the central dosimeter and the left and/or right dosimeters. Then, the absolute dose is determined by correcting the angular dependence of the central dosimeter based on the estimated θin. In order to verify the concept of the triple-type dosimeter, we conducted a proof-of-concept experiment using clinical X-ray fluoroscopic equipment. Scattered X-rays were generated by irradiating an elliptical cylindrical water phantom. The response of the triple-type dosimeter was evaluated by rotating it to vary the incident angle of scattered X-rays generated by the water phantom. The proposed dosimetry system could estimate the θin over an angular range of ±80° (with uncertainty of 1.35°), which is 30° wider than the previous version, and successfully determined the absolute doses after correction for the angular dependence of the dosimeter. Although the active-type dosimeter had a systematic uncertainty related to the angular dependence of ±15.2 %, our system succeeded in reducing the systematic uncertainty to ±3.2 %. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2025 Influences of land-use changes and water management strategies for water availability of coffee cultivation in the Srepok River Watershed, Vietnam EN TRUONG THAO SAM Graduate School of Environmental and Life Science, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2025 Improving sediment microbial fuel cells for water quality control in shrimp pond drainages in Central Vietnam EN NGUYEN TU UYEN Graduate School of Environmental and Life Science, Okayama University No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 17 4 2025 Subcutaneous and Periorbital Emphysema Following a Dental Procedure e83089 EN Takafumi Obara Department of Emergency, Critical Care and Disaster Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences Okayama University Tsuyoshi Nojima Department of Emergency, Critical Care and Disaster Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences Okayama University Kazuki Nakatsuji Department of Oral and Maxillofacial Reconstructive Surgery, Okayama University Hospital Takashi Hongo Department of Emergency, Critical Care and Disaster Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences Okayama University Tetsuya Yumoto Department of Emergency, Critical Care and Disaster Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences Okayama University Atsunori Nakao Department of Emergency, Critical Care and Disaster Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences Okayama University Subcutaneous emphysema following dental procedures is rare. We present the case of a young, healthy woman who was transferred from a dental clinic to our emergency department due to sudden swelling of the left orbit immediately after a dental procedure involving the use of the dental air and water syringe. The diagnosis of subcutaneous facial emphysema was made based on the patient's history, physical examination, and computed tomography imaging. The patient received prophylactic amoxicillin, and the lesion resolved completely in one week. Prompt clinical suspicion and a thorough evaluation of the signs and symptoms, including a detailed clinical history, are crucial for diagnosing subcutaneous emphysema following a dental procedure. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1085-3278 2025 Enhancing Soil Aggregation and Water Retention by Applying Kaolinite Clay to Post‐Tin‐Mined Land on Belitung Island, Indonesia EN Hirmas F. Putra Graduate School of Environmental and Life Science, Okayama University Yasushi Mori Graduate School of Environmental and Life Science, Okayama University Post-mining sandy soils have low water retention, which causes soil particle separation and persistent soil erosion. Although organic matter is commonly used for soil restoration, it is lightweight, washes away during heavy rain, and decomposes under strong sunlight. The high potential for extreme rainfall events in tropical regions poses significant challenges to restoration projects. Therefore, we investigated the impact of kaolinite clay particles on enhancing soil stability in post-mining sandy soils. Soil samples were collected from three sites representing different succession stages of post-mined land (0, 1, and 6 years since mining cessation) and an adjacent natural forest as the reference site on Belitung Island, Indonesia. Soil samples were treated with 1% or 5% kaolinite or left untreated (control) and incubated at 34°C to mimic the local conditions of the study area. The samples were then analyzed to determine the soil aggregate distribution, water holding capacity, and soil erodibility, and SEM imaging was performed to examine the soil particle morphology. The results revealed an increasing trend in the silt-sized aggregate content and a 2%–5% increase in water retention in the 6-year soils relative to the untreated soils. The highest water retention was observed in the 6-year post-mining soil sample. Kaolinite amendment significantly reduced soil erodibility by 40%–50% compared to the untreated soils, even in the early restoration period (0–1 year post-mining). Kaolinite improved soil aggregation and water retention in post-mining sandy soils while reducing soil erodibility—highlighting its potential for accelerating land restoration in mining-affected areas. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0341-8162 254 2025 Cellulose nanofibers boost soil water availability, plant growth, and irrigation water use efficiency under deficit irrigation 108998 EN An Thuy Ngo Graduate School of Environmental and Life Science, Okayama University Manh Cong Nguyen Nong Lam University Morihiro Maeda Graduate School of Environmental and Life Science, Okayama University Yasushi Mori Graduate School of Environmental and Life Science, Okayama University Under climate change, even previously rainfall-prone areas may experience droughts, and effective strategies are vital for soil conservation. Owing to their cutting-edge water absorption and storage properties, cellulose nanofibers (CNF) are expected to increase soil water availability and help plants resist water stress. However, the role of CNF in improving plant growth and soil water retention under various irrigation regimes is not yet known. We evaluated the effects of CNFs on plant available water (PAW), germination, plant growth, and irrigation water use efficiency (IWUE) under both adequate and deficit irrigation conditions. Plant cultivation experiments were conducted using different CNF dosages (0%, 0.1%, 0.5%, and 1.0%), irrigation levels (I100, I50, and I25), and soil types (sandy and silty loam). The results indicated that CNF significantly increased field capacity (FC) and PAW in both soil types, with PAW in CNF-amended soils increasing by up to 110% and 88% in sandy and silty loam soil, respectively, at 1% CNF dosage. In germination tests, CNF showed no phytotoxicity and supported the germination process during water stress, with enhancements of up to 64% and 163% at I50 and up to 125% and 214% at I25 in germination percentage and germination index, respectively. Plant growth experiments revealed that CNF addition helped plants resist water stress, maintaining plant height and weight close to those under full irrigation, while using 50% less water. IWUE analyses demonstrated that CNF enhanced IWUE, with increases of up to 56% under sufficient watering (I100), 169% under moderate water stress (I50), and 120% under severe water stress (I25), at 1% CNF dosage. These findings highlight the potential of CNF as a multifaceted amendment, offering practical solutions for addressing water scarcity challenges and contributing to more resilient and sustainable agricultural practices. No potential conflict of interest relevant to this article was reported.

Japanese Society of Tribologists Acta Medica Okayama 1881-2198 20 3 2025 Water Lubrication of Polysiloxane-Containing Polyimide Coatings on Stainless Steel Substrates 124 129 EN Yuelin Fan Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tadashi Shiota Faculty of Environmental, Life, Natural Science and Technology, Okayama University Yuya Omiya Faculty of Environmental, Life, Natural Science and Technology, Okayama University Masahiro Fujii Faculty of Environmental, Life, Natural Science and Technology, Okayama University This study investigated the water-lubricated tribological properties of coatings made of a novel polysiloxane-containing polyimide (si-PI) material that was recently developed for the aerospace industry and can be diluted with the harmless and environmentally friendly ethanol or water. The si-PI coatings were deposited on stainless steel (JIS SUS304) substrates at curing temperatures ranging from 160°C to 275°C. Their water lubrication properties were measured by rubbing the coatings against each other in water at room temperature. The coatings exhibited lower friction than conventional polyimide materials, with a minimum friction coefficient of 0.04, which was lower than that of polytetrafluoroethylene (PTFE) measured under the same sliding conditions. Unlike the conventional polyimide, the coatings did not exhibit any obvious wear or damage. The results demonstrate that the si-PI coating is a promising low-friction and highly durable coating for water lubrication. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1744-683X 21 43 2025 Effect of the pH value on compression and array structures of highly charged microgels at the air/water interface 8323 8333 EN Takahisa Kawamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruka Minato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Daisuke Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Understanding the interfacial behavior of stimuli-responsive microgels is critical for applications such as foam and emulsion stabilization, as well as for the fabrication of two-dimensional colloidal crystals using the interfaces. In this study, the pH-dependent compression behavior and array structures of micron-sized poly(N-isopropylacrylamide-co-acrylic acid) microgels at the air/water interface was investigated. By combining a Langmuir trough with fluorescence microscopy, microgel arrays under compression and acidic (pH = 3) or basic (pH = 9) conditions were directly visualized. At pH = 9, the carboxyl groups within the microgels are deprotonated, resulting in significant swelling and the formation of ordered hexagonal arrays with high crystallinity (Ψ6 > 0.84) upon compression. In contrast, at pH = 3, the carboxyl groups within the microgels are protonated, leading to a suppression of the electrostatic repulsion between neighboring microgels and a reduction in crystallinity (Ψ6 ∼ 0.70) of the microgel arrays before and after compression. Furthermore, the calculated surface-compression modulus using the compression isotherms indicated higher interfacial elasticity for charged microgels, demonstrating that electrostatic repulsion governs both array ordering and mechanical robustness. These findings provide fundamental insights into the role of charge in controlling the microgel structure and mechanics at interfaces, thus offering further guidelines for the design of stimuli-responsive materials and stabilizers for foams and emulsions. No potential conflict of interest relevant to this article was reported.

American Geophysical Union (AGU) Acta Medica Okayama 2169-9313 130 10 2025 Electrical Conductivity of Carbonated Hydrous Basaltic Melt: Implications for the Conductivity Anomaly Beneath the Ocean Floors e2025JB032215 EN Bin Zhao Institute for Planetary Materials, Okayama University Jintao Zhu Institute for Planetary Materials, Okayama University Jinze He Institute for Planetary Materials, Okayama University Takashi Yoshino Institute for Planetary Materials, Okayama University We measured the electrical conductivity of CO2 and H2O-bearing basaltic melts up to 1750 K at 2 GPa, corresponding to pressure around the lithosphere-asthenosphere boundary. The electrical conductivity of the dry and hydrous samples is comparable to those reported by previous studies on the Fe-free basaltic melt. The substantial CO2 can limit the water solubility in basaltic melt at 2 GPa. Both CO2 and H2O, which cannot completely dissolve in the melt, coexist as fluid phases, resulting in reduced electrical conductivity of the basaltic melt, which has a lower water content relative to the amount of volatile components in the bulk starting system. The activation enthalpy of basaltic melt is markedly higher than those of more evolved silicate melts, especially on the H2O-poor condition, due to the more enriched alkaline earth elements. The present results suggest that an overall melt fraction of 0.1–5.3 vol% is needed to account for the high electrical conductivity anomalies (10−1.3 to 10−0.3 S/m) beneath the oceanic plate near the East Pacific Rise and Cocos plate. However, for those regions where the electrical conductivity is extremely high (≥10−0.3 S/m), more than 6 wt% H2O is expected to incorporate to maintain a melt fraction that will not trigger mechanical instability. In turn, it requires a low CO2 budget or degree of carbonation within these regions. No potential conflict of interest relevant to this article was reported.

Japan Society of Hydrology and Water Resources Acta Medica Okayama 1882-3416 19 4 2025 Unique drought tendency of an understudied region in the Mekong Delta, Vietnam 223 230 EN Yu Tsuha Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Vo Ngoc Quynh Tram Research Center for Climate Change, Nong Lam University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University Water resource vulnerability due to uneven precipitation and water allocations is a significant issue in many regions of the world, including the Mekong Delta. Although numerous studies have already evaluated drought tendencies in many parts of the Mekong Delta, some areas have been excluded. This study targeted these excluded areas, including one inland, one coastal area, and two islands, which are defined as “understudied regions.” The meteorological drought intensity, frequency, and duration in the study areas in the Mekong Delta were evaluated using different time scales of the Standardized Precipitation Index (SPI) between 1994–2020. Unique contrasts in drought features were found between the study areas, indicating that severe drought events occupied the highest percentages inland from 2011 onward, while the most extreme drought events occurred in the coastal areas. Furthermore, trends in drought intensity, tendency, frequency, and duration were identified within the same delta region, demonstrating that combining SPI with other indicators can detect drought patterns in the Mekong Delta. These findings emphasize the importance of comprehensive evaluation of drought tendencies, including in understudied regions, for a better understanding of the features and future of water resources management. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2398-4902 2025 Activation of barium titanate for photocatalytic overall water splitting via low-valence cation codoping EN Shigeru Ikeda Faculty of Science and Engineering, Konan University Kaori Takagi Faculty of Science and Engineering, Konan University Ryota Tomizawa Carbon Neutral Energy Development Division, Toyota Motor Corporation Tomoya Nagano Carbon Neutral Energy Development Division, Toyota Motor Corporation Koji Hayashi Carbon Neutral Energy Development Division, Toyota Motor Corporation Akira Yamakata Research Institute for Interdisciplinary Science, Okayama University Yoshitaro Nose Department of Materials Science and Engineering, Kyoto University Barium titanate (BaTiO3) has long been regarded as inactive for photocatalytic overall water splitting, in stark contrast to its perovskite counterparts SrTiO3 and CaTiO3. Here we report that BaTiO3 codoped with Al3+ and Sc3+ at Ti4+ sites under flux synthesis conditions is activated as a robust photocatalyst for overall water splitting. This material achieves apparent quantum yields of 29.8% at 310 nm and 27.5% at 365 nm, representing the first demonstration of efficient overall water splitting on BaTiO3. Comparative analyses show that BaTiO3 doped only with Al3+ suffers from severe band-edge disorder, whereas BaTiO3 codoped with Al3+ and Mg2+ exhibits clear activation with moderate efficiency. In contrast, BaTiO3 codoped with Al3+ and Sc3+ achieves the critical defect and structural control required to push the material across the threshold from inactive to highly active. These findings overturn the long-standing perception of BaTiO3 as unsuitable for water splitting and establish a general design principle for activating previously inactive perovskite oxides, thereby expanding the materials palette for solar-to-hydrogen energy conversion. No potential conflict of interest relevant to this article was reported.

Japan Society on Water Environment Acta Medica Okayama 1348-2165 23 5 2025 Biochar-amended Sediment Microbial Fuel Cells for Water Quality Improvement in Intensive and Extensive Pond Drainages in Central Vietnam 234 249 EN Uyen Tu Nguyen Graduate School of Environmental and Life Science, Okayama University Morihiro Maeda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroaki Somura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nozomi Nakahara Department of Comprehensive Technical Solutions, Okayama University Gamamada Liyanage Erandi Priyangika Perera Graduate School of Environmental and Life Science, Okayama University Chiyu Nakano Graduate School of Environmental and Life Science, Okayama University Huu Tien Le Department of Education, Science and Technology Quang Tri Branch, Hue University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University The use of nutrient-rich feed in shrimp farming in Central Vietnam has led to high nitrogen (N) and phosphorus (P) contents in the pond sediment. The objectives of the study were to assess the effectiveness of biochar-sediment microbial fuel cells (BC-SMFCs) in suppressing P and N release from two types of sediment in intensive (Int) and extensive (Ext) pond drainages in Central Vietnam. Single chamber SMFCs were set up and operated under open or closed-circuit (no SMFC or SMFC) conditions. Coconut shell biochar (BC) was amended to sediments at 1%. For Int-sediment, total phosphorus (TP) release was reduced by no BC-SMFCs through co-precipitation with Fe. On the other hand, BC-SMFCs did not suppress TP release because P was released from BC and organic matter decomposition was enhanced in the sediment. Application of BC enhanced organic N mineralization in the sediment. Nitrification and denitrification occurred in the overlying water, reducing mineral N concentrations. For Ext-sediment, BC addition and SMFC conditions did not affect TP and total nitrogen (TN) release because of low initial organic matter content, and less reductive condition. Our study suggested that the effect of SMFCs was masked by BC which released more P from Int-sediment to the water. No potential conflict of interest relevant to this article was reported.

American Geophysical Union (AGU) Acta Medica Okayama 2169-9313 130 1 2025 Reduced Thermal Conductivity of Hydrous Aluminous Silica and Calcium Ferrite‐Type Phase Promote Water Transportation to Earth's Deep Mantle e2024JB030704 EN Wen‐Pin Hsieh Institute of Earth Sciences, Academia Sinica Takayuki Ishii Institute for Planetary Materials, Okayama University Frédéric Deschamps Institute of Earth Sciences, Academia Sinica Yi‐Chi Tsao Institute of Earth Sciences, Academia Sinica Jen‐Wei Chang Institute of Earth Sciences, Academia Sinica Giacomo Criniti Earth and Planets Laboratory, Carnegie Institution for Science Subduction of oceanic slabs introduces chemical heterogeneities in the Earth's interior, which could further induce thermal, seismic, and geodynamical anomalies. Thermal conductivity of slab minerals crucially controls the thermal evolution and dynamics of the subducted slab and ambient mantle, while such an important transport property remains poorly constrained. Here we have precisely measured high pressure-temperature thermal conductivity of hydrous aluminous post-stishovite (ΛHy-Al-pSt) and aluminum-rich calcium ferrite-type phase (ΛCF), two important minerals in the subducted basaltic crust in the lower mantle. Compared to the dry aluminous stishovite and pure stishovite, hydration substantially reduces the ΛHy-Al-pSt, resulting in ∼9.7–13.3 W m−1 K−1 throughout the lower mantle. Surprisingly, the ΛCF remains at ∼3–3.8 W m−1 K−1 in the lower mantle, few-folds lower than previously assumed. Our data modeling offers better constraints on the thermal conductivity of the subducted oceanic crust from mantle transition zone to the lowermost mantle region, which is less thermally conductive than previously modeled. Our findings suggest that if the post-stishovite carries large amounts of water to the lower mantle, the poorer heat conduction through the basaltic crust reduces the slab's temperature, which not only allows the slab bringing more hydrous minerals to greater depth, but also increases slab's density and viscosity, potentially impacting the stability of heterogeneous structures at the lowermost mantle. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0008-6223 243 2025 Organic solvent transport through reduced graphene oxide membranes with controlled oxygen content 120539 EN Hongzhe Chen School of Materials Science and Engineering, University of New South Wales Sydney Tongxi Lin School of Materials Science and Engineering, University of New South Wales Sydney Zeno Rizqi Ramadhan Electron Microscope Unit, University of New South Wales Aditya Rawal Mark Wainwright Analytical Centre, University of New South Wales Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Amir Karton School of Science and Technology, University of New England Xiaojun Ren School of Materials Science and Engineering, University of New South Wales Sydney Rakesh Joshi School of Materials Science and Engineering, University of New South Wales Sydney Recent advances in membranes based on 2-dimensional (2D) materials have enabled precise control over angstrom-scale pores, providing a unique platform for studying diverse mass transport mechanisms. In this work, we systematically investigate the transport of solvent vapors through 2D channels made of graphene oxide (GO) laminates with precisely controlled oxygen content. Using in-situ chemical reduction of GO with vitamin C, we fabricated reduced GO membranes (VRGMs) with oxygen content systematically decreased from 31.6 % (pristine GO) to 24.0 % (VRGM-maximum reduction). Vapor permeability measurements showed a distinct correlation between oxygen functional groups and solvent transport behaviour. Specifically, non-polar hexane exhibits 114 % of enhanced permeance through the reduced membranes with larger graphitic domains, while the permeance of water decreases by 55 %. With the support of density functional theory (DFT) simulations, we modelled the hydrogen-bond and dispersion complexes between the solvents and GO and calculated the complexation energies. The simulation results suggest that polar molecules interact with the oxygen functional groups of GO via a hydrogen-bond network, supporting in-plane transport. In contrast, van der Waals forces drive the transport of low-polarity solvents along the graphitic domains of the 2D channel in reduced GO membranes. Our findings provide potential strategies for future design of organic solvent nanofiltration membranes. No potential conflict of interest relevant to this article was reported.

IOP Publishing Acta Medica Okayama 2053-1583 12 4 2025 Covalent cross-linked graphene oxide aerogels for moisture adsorption 045010 EN Zhijian Cao School of Materials Science and Engineering, University of New South Wales Xiaojun Ren School of Materials Science and Engineering, University of New South Wales Tongxi Lin School of Materials Science and Engineering, University of New South Wales Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Masamichi Yoshimura Graduate School of Engineering, Toyota Technological Institute Rakesh Joshi School of Materials Science and Engineering, University of New South Wales Covalent cross-linking is an effective approach to enhance the hydrophilicity and water adsorption properties of graphene oxide (GO). We studied moisture absorption in GO cross-linked with poly(ethylene glycol) diamines. At relative humidity (RH) of 85%, the PEG-cross-linked GO exhibited a significantly enhanced water uptake capacity of 0.59 g of water per gram of GO (gg−1), compared to 0.37 for unmodified GO. This is attributed to the presence of alkoxy groups via cross-linking, resulting in the enhanced interaction between GO and water molecules. These findings highlight the potential of PEG-based covalent functionalisation for efficient moisture capture in GO-based materials. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0012-821X 658 2025 Limited water contents of wadsleyite and ringwoodite coexisting with hydrous minerals in cold subducting slabs 119310 EN Takayuki Ishii Institute for Planetary Materials, Okayama University Jintao Zhu Institute for Planetary Materials, Okayama University Eiji Ohtani Department of Earth Sciences, Graduate School of Science, Tohoku University How water is distributed in a subducting slab is essential to understand water transport into the deep mantle and mechanisms of deep-focus earthquakes and slab deformation around the 660-km discontinuity. A recent experimental study demonstrated that water contents of olivine and wadsleyite coexisting with hydrous phase A is limited at upper mantle pressures, suggesting strong water partitioning to the hydrous phase. However, water distribution between nominally anhydrous and hydrous minerals at the deeper mantle is not investigated in detail. We determined water contents in wadsleyite and ringwoodite coexisting with hydrous phases down to transition-zone depths along cold slab temperatures. Wadsleyite coexisting with hydrous phase A has ∼200 ppm water at 14–16 GPa and 800 °C. At 21 GPa, ringwoodite coexisting with superhydrous phase B has 8–13 ppm water at 800 °C and 46 ppm at 900 °C. Thus, olivine and its high-pressure polymorphs are kinetically dry along cold slab core conditions even in a wet subducting slab. Slab deformation and stagnation around 660 km depth can be caused by grain-size reduction due to phase transitions of dry olivine and the presence of rheologically weak hydrous phases. The deepest earthquakes below 660 km depth can be caused by dehydration of hydrous phases. No potential conflict of interest relevant to this article was reported.

Ceramic Society of Japan Acta Medica Okayama 1348-6535 133 1 2025 Comparative study of the effects of fluoride treatment with cyclic variations in pH on the structures of stoichiometric, calcium-deficient, and carbonated hydroxyapatites 15 24 EN Satoshi Hayakawa Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yu Okada Graduate School of Natural Science and Technology, Okayama University Tomohiko Yoshioka Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University The primary objective of this study was to analyze the effects of fluoride treatment with cyclic variations in pH on the structure of stoichiometric hydroxyapatite (HAp), calcium-deficient HAp (CDHAp), and carbonated HAp (CHAp) powders. The structures of HAp, CDHAp, and CHAp before and after fluoride treatment were investigated using X-ray diffraction, Fourier-transform infrared, Raman, and nuclear magnetic resonance spectroscopic analyses. The fluoride treatment with cyclic variations in pH increased the calcium deficiency in HAp and CHAp but decreased in CDHAp. During fluoride treatment, fluoridated CDHAp or fluoridated calcium-deficient CHAp was formed on the surface of the HAp samples via dissolution and crystal growth, accompanied by the selective elution of component ions and partial substitution of OH− groups in the HAp hexagonal lattice with F− ions. No evidence of the formation of Ca(OH)2 and OH− groups outside the HAp crystal lattice was obtained. A new perspective on the formation of structured water at the surface termination of the OH columns (disordered region), with possible interactions with adsorbed water molecules or nonspecifically adsorbed F− ions was provided. The top surface of the fluoridated CDHAp consisted of an amorphous fluoride-rich hydrated layer, which included calcium phosphate and CaF2. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1609-0985 2025 An Alternative Approach Based on Skin Electrical Impedance to Determine Transepidermal Water Loss for Skin Barrier Function Assessments EN Osamu Uehara Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Takao Nakamura Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Purpose: The transepidermal water loss (TEWL) has long been measured as an indicator to assess the skin barrier function in dermatological research and clinical practice. However, practical limitations such as time requirement, environmental sensitivity, and measurement complexity hinder the widespread uptake of conventional TEWL measurements in clinical settings and routine monitoring. Consequently, there is a growing need for rapid, robust, and clinically applicable alternatives to conventional TEWL measurements. Here, we present a simple, non-invasive, and time-efficient method based on the skin electrical impedance for skin barrier function assessments.<br> Methods: The skin electrical impedance, TEWL, stratum corneum (SC) thickness, and SC surface water content of 25 healthy adult participants with no history of dermatological diseases were measured at two adjacent forearm sites: intact site with a normal skin barrier and tape-stripped site with an impaired skin barrier. The measured impedance was used to calculate the SC thickness and surface water content, from which the TEWL was estimated and then compared against the TEWL measured using a Tewameter. The estimation accuracy was evaluated by determining the correlation coefficient (R) and root mean square error (RMSE) between estimated and measured TEWL.<br> Results: A strong correlation (R = 0.891) was observed between estimated and measured TEWL, with an RMSE of 6.05 g/m²/h, indicating high accuracy of the proposed method.<br> Conclusion: This impedance-based method provides accurate estimations of the TEWL, indicating its potential as a practical alternative to conventional TEWL measurements for skin barrier function assessments, particularly in clinical or high-throughput settings. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2073-4409 14 17 2025 Discovery and Functional Characterization of Novel Aquaporins in Tomato (Solanum lycopersicum): Implications for Ion Transport and Salinity Tolerance 1305 EN Newton Chandra Paul Institute of Plant Science and Resources, Okayama University Shahin Imran Institute of Plant Science and Resources, Okayama University Anri Mitsumoto Institute of Plant Science and Resources, Okayama University Izumi C. Mori Institute of Plant Science and Resources, Okayama University Maki Katsuhara Institute of Plant Science and Resources, Okayama University Aquaporins (AQPs) are membrane proteins that facilitate the transport of water and solutes. Among AQPs, plasma membrane intrinsic proteins (PIPs) play a critical role in maintaining water balance between the internal and external cell environments. This study focuses on the tomato due to its economic importance and cultivation under moderate salinity conditions in Japan. A swelling assay using X. laevis oocyte confirmed that all five examined tomato SlPIP2 isoforms showed water transport activity. Among them, two-electrode voltage clamp (TEVC) experiments showed that only SlPIP2;1, SlPIP2;4, and SlPIP2;8 transport Na+ and K+, with no transport activity for Cs+, Rb+, Li+, or Cl−. CaCl2 (1.8 mM) reduced ionic currents by approximately 45% compared to 30 µM free-Ca2+. These isoforms function as very low-affinity Na+ and K+ transporters. Expression analysis showed that SlPIP2;4 and SlPIP2;8 had low, stable expression, while SlPIP2;1 was strongly upregulated in roots NaCl treatment (200 mM, 17days), suggesting distinct physiological roles for these ion-conducting AQPs (icAQPs). These data hypothesized that tomato icAQPs play a critical role in ion homeostasis, particularly under salinity stress. In conclusion, the first icAQPs have been identified in the dicotyledonous crop. These icAQPs are essential for plant resilience under salt stress. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0956-5663 287 2025 A plant-insertable multi-enzyme biosensor for the real-time monitoring of stomatal sucrose uptake 117674 EN Shiqi Wu Graduate School of Information, Production and Systems, Waseda University Wakutaka Nakagawa Graduate School of Information, Production and Systems, Waseda University Yuki Mori Faculty and Graduate School of Environmental Engineering, The University of Kitakyushu Saman Azhari Graduate School of Information, Production and Systems, Waseda University Gábor Méhes Graduate School of Information, Production and Systems, Waseda University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Tomonori Kawano Faculty and Graduate School of Environmental Engineering, The University of Kitakyushu Takeo Miyake Graduate School of Information, Production and Systems, Waseda University Monitoring sucrose transport in plants is essential for understanding plant physiology and improving agricultural practices, yet effective sensors for continuous and real-time in-vivo monitoring are lacking. In this study, we developed a plant-insertable sucrose sensor capable of real-time sucrose concentration monitoring and demonstrated its application as a useful tool for plant research by monitoring the sugar-translocating path from leaves to the lower portion of plants through the stem in living plants. The biosensor consists of a bilirubin oxidase-based biocathode and a needle-type bioanode integrating glucose oxidase, invertase, and mutarotase, with the two electrodes separated by an agarose gel for ionic connection. The sensor exhibits a sensitivity of 6.22 μA mM−1 cm−2, a limit of detection of 100 μM, a detection range up to 60 mM, and a response time of 90 s at 100 μM sucrose. Additionally, the sensor retained 86 % of its initial signal after 72 h of continuous measurement. Day-night monitoring from the biosensor inserted in strawberry guava (Psidium cattleianum) showed higher sucrose transport activity at night, following well the redistribution of photosynthetically produced sugars. In addition, by monitoring the forced translocation of sucrose dissolved in the stable isotopically labeled water, we demonstrated that a young seedling of Japanese cedar known as Sugi (Cryptomeria japonica) can absorb and transport both water and sucrose through light-dependently opened stomata, which is the recently revealed path for liquid uptake by higher plants. These findings highlight the potential of our sensor for studying dynamic plant processes and its applicability in real-time monitoring of sugar transport under diverse environmental conditions. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0360-3199 101 2025 Next frontier in photocatalytic hydrogen production through CdS heterojunctions 173 211 EN Aminul Islam Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Abdul Malek Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Md. Tarekul Islam Department of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and Technology Farzana Yeasmin Nipa Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Obayed Raihan Department of Pharmaceutical Sciences, College of Health Sciences and Pharmacy, Chicago State University Hasan Mahmud Bangladesh Energy and Power Research Council (BEPRC) Md. Elias Uddin Department of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and Technology Mohd Lokman Ibrahim School of Chemistry and Environment, Faculty of Applied Sciences, Universiti Teknologi MARA G. Abdulkareem-Alsultan Catalysis Science and Technology Research Centre, Faculty of Science, Universiti Putra Malaysia Alam Hossain Mondal USAID - Bangladesh Advancing Development and Growth through Energy (BADGE) Project, Tetra Tech Md. Munjur Hasan Department of Chemistry, Graduate School of Science, Osaka University Md. Shad Salman Institute for Chemical Research, Kyoto University Khadiza Tul Kubra Department of Chemistry, Graduate School of Science, Osaka University Md. Nazmul Hasan Department of Chemistry, School of Science, The University of Tokyo Md. Chanmiya Sheikh Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tetsuya Uchida Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Adiba Islam Rasee Department of Chemistry, Graduate School of Science, Osaka University Ariyan Islam Rehan Department of Chemistry, School of Science, The University of Tokyo Mrs Eti Awual Institute for Chemical Research, Kyoto University Mohammed Sohrab Hossain Department of Chemistry, Graduate School of Science, Osaka University R.M. Waliullah Institute for Chemical Research, Kyoto University Md. Rabiul Awual Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University Photocatalytic hydrogen (H₂) generation via solar-powered water splitting represents a sustainable solution to the global energy crisis. Cadmium sulfide (CdS) has emerged as a promising semiconductor photocatalyst due to its tunable bandgap, high physicochemical stability, cost-effectiveness, and widespread availability. This review systematically examines recent advancements in CdS-based heterojunctions, categorized into CdS-metal (Schottky), CdS-semiconductor (p-n, Z-scheme, S-scheme), and CdS-carbon heterojunctions. Various strategies employed to enhance photocatalytic efficiency and stability are discussed, including band structure engineering, surface modification, and the incorporation of crosslinked architectures. A critical evaluation of the underlying photocatalytic mechanisms highlights recent efforts to improve charge separation and photostability under operational conditions. This review highlights the challenges and opportunities in advancing CdS-based photocatalysts and provides a direction for future research. The insights presented aim to accelerate the development of efficient and durable CdS-based photocatalysts for sustainable H₂ production. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1438-4957 2025 From sewage sludge to agriculture: governmental initiatives, technologies, and sustainable practices in Japan EN Thu Huong Nguyen Graduate School of Engineering, Kyoto University Taku Fujiwara Graduate School of Engineering, Kyoto University Hiromasa Yamashita Water Supply and Sewerage Department, National Institute for Land and Infrastructure Management Hironori Togawa Water Supply and Sewerage Department, National Institute for Land and Infrastructure Management Haruo Miyake R & D Department, Japan Sewage Works Agency Masako Goto 1St Research Department, Japan Institute of Wastewater Engineering and Technology Hideaki Nagare Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Masato Nakamura Institute for Rural Engineering, NARO Fumiko Oritate Institute for Rural Engineering, NARO Hirotaka Ihara Institute for Agro-Environmental Sciences, NARO Morihiro Maeda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Sewage sludge (SS), an underutilized but valuable resource for agriculture, contains essential nutrients, such as phosphorus. In Japan, where dependence on imported fertilizers is high and global price fluctuations persist, using SS as fertilizer presents a sustainable alternative aligned with circular economy goals. This review analyzes Japan’s current efforts to repurpose SS, focusing on technological developments and key policy initiatives that promote safe and effective application. Selective phosphorus recovery technologies mitigate resource depletion, while holistic approaches, such as composting and carbonization, maximize sludge utilization for agricultural applications. Government-led initiatives, including public awareness campaigns, quality assurance standards and research support, have facilitated the adoption of sludge-based fertilizers. To contextualize Japan’s position, international trends, particularly in the EU, are also examined. These comparisons reveal both common strategies and areas for policy and technological advancement, especially regarding regulation of emerging contaminants. By integrating national case studies with global perspectives, the study offers insights into the economic, environmental, and social benefits of SS reuse, contributing to Japan’s goals of resource self-sufficiency and carbon neutrality, while also informing broader sustainable agriculture transitions worldwide. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0001-8686 343 2025 Progress in silicon-based materials for emerging solar-powered green hydrogen (H2) production 103558 EN Aminul Islam Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Md. Tarekul Islam Department of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and Technology Siow Hwa Teo Industrial Chemistry Program, Faculty of Science and Natural Resources, Universiti Malaysia Sabah Hasan Mahmud Bangladesh Energy and Power Research Council (BEPRC) A.M. Swaraz Department of Genetic Engineering and Biotechnology, Jashore University of Science and Technology Ariyan Islam Rehan Department of Chemistry, School of Science, The University of Tokyo Adiba Islam Rasee Department of Chemistry, Graduate School of Science, Osaka University Khadiza Tul Kubra Department of Chemistry, Graduate School of Science, Osaka University Md. Munjur Hasan Department of Chemistry, Graduate School of Science, Osaka University Md. Shad Salman Institute for Chemical Research, Kyoto University R.M. Waliullah Institute for Chemical Research, Kyoto University Md. Nazmul Hasan Department of Chemistry, School of Science, The University of Tokyo Md. Chanmiya Sheikh Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tetsuya Uchida Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Mrs Eti Awual Department of Chemistry, Graduate School of Science, Osaka University Mohammed Sohrab Hossain Department of Chemistry, Graduate School of Science, Osaka University Hussein Znad Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University Md. Rabiul Awual Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University The imperative demand for sustainable and renewable energy solutions has precipitated profound scientific investigations into photocatalysts designed for the processes of water splitting and hydrogen fuel generation. The abundance, low toxicity, high conductivity, and cost-effectiveness of silicon-based compounds make them attractive candidates for hydrogen production, driving ongoing research and technological advancements. Developing an effective synthesis method that is simple, economically feasible, and environmentally friendly is crucial for the widespread implementation of silicon-based heterojunctions for sustainable hydrogen production. Balancing the performance benefits with the economic and environmental considerations is a key challenge in the development of these systems. The specific performance of each catalyst type can vary depending on the synthesis method, surface modifications, catalyst loading, and reaction conditions. The confluence of high crystallinity, reduced oxygen concentration, and calcination temperature within the silicon nanoparticle has significantly contributed to its noteworthy hydrogen evolution rate. This review provides an up-to-date evaluation of Si-based photocatalysts, summarizing recent developments, guiding future research directions, and identifying areas that require further investigation. By combining theoretical insights and experimental findings, this review offers a comprehensive understanding of Si-based photocatalysts for water splitting. Through a comprehensive analysis, it aims to elucidate existing knowledge gaps and inspire future research directions towards optimized photocatalytic performance and scalability, ultimately contributing to the realization of sustainable hydrogen generation. No potential conflict of interest relevant to this article was reported.

Japan Society on Water Environment Acta Medica Okayama 1348-2165 23 2 2025 Study on the Removal Technology of Trichloramine from Drinking Water Using Ultraviolet Light 71 81 EN Ayumi Hashiguchi Faculty of Environmental, Life, Natural Science and Technology, Okayama University Shiho Yoshida Graduate School of Natural Science and Technology, Shimane University Shinya Echigo Graduate School of Global Environmental Studies, Kyoto University Ryohei Takanami Faculty of Design Technology, Osaka Sangyo University Hideaki Nagare Faculty of Environmental, Life, Natural Science and Technology, Okayama University Trichloramine (NCl3) is an inorganic chloramine that causes a pungent chlorine-like odor, and it is difficult to remove its precursors (nitrogen organic compounds and/or ammonia) completely from water. Powdered activated carbon, ozonation, and UV treatment have been applied for decomposing NCl3, but free chlorine was also decomposed. So, it is necessary to develop a technique that can selectively control NCl3 without losing free chlorine. UV light-emitting diodes (265, 280, and 300 nm) and plasma emission UV sheet (347 ± 52 nm, hereafter 350 nm) were compared to find the optimal wavelengths that decompose NCl3 but not free chlorine. As a result, 90.6, 96.7, 92.5, and 77.8% of NCl3 were removed at 265, 280, 300 (3,600 mJ/cm2), and 350 nm (14,400 mJ/cm2), respectively. On the other hand, free chlorine at neutral pH (hypochlorous acid is dominant) and slightly alkaline pH (hypochlorite ion is dominant) was not decomposed at 350 nm, but at other wavelengths (i.e., 265, 280, and 300 nm) the removals were more than 64%. Therefore, UV radiation at 350 nm can be candidates to remove NCl3 while maintaining free chlorine. However, this method requires high input energy, and further study is needed for evaluating the practical applicability of this method by considering optimal reactor design. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0002-8177 156 2 2025 The greater palatine nerve and artery both supply the maxillary teeth 151 159.e1 EN Joe Iwanaga Division of Gross and Clinical Anatomy, Department of Anatomy, School of Medicine, Kurume University Yohei Takeshita Department of Oral and Maxillofacial Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Muralidharan Anbalagan Department of Structural and Cellular Biology, School of Medicine, Tulane University Binghao Zou Department of Structural and Cellular Biology, School of Medicine, Tulane University Taku Toriumi Department of Anatomy, School of Life Dentistry at Niigata, The Nippon Dental University Yuki Kunisada Department of Oral and Maxillofacial Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Soichiro Ibaragi Department of Oral and Maxillofacial Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University R. Shane Tubbs University of Queensland Background. It is generally accepted that the greater palatine nerve and artery supply the palatal mucosa, gingiva, and glands, but not the bone or tooth adjacent to those tissues. When the bony palate is observed closely, multiple small foramina are seen on the palatal surface of the alveolar process. The authors hypothesized that the greater palatine nerve and artery might supply the maxillary teeth via the foramina on the palatal surface of the alveolar process and the superior alveolar nerve and artery. The authors aimed to investigate the palatal innervation and blood supply of the maxillary teeth.<br> Methods. Eight cadaveric maxillae containing most teeth or alveolar sockets were selected. The mean age at the time of death was 82.4 years. The samples were examined with colored water injection, latex injection, microcomputed tomography with contrast dye, gross anatomic dissection, and histologic observation.<br> Results. Through both injection studies and microcomputed tomographic analysis, the authors found that the small foramina on and around the greater palatine groove connected to the alveolar process and tooth sockets. The small foramina in the greater palatine and incisive canal also continued inside the alveolar process and the tooth sockets.<br> Conclusions. The alveolar branches of the greater palatine nerve and artery as well as the nasopalatine nerve and sphenopalatine artery supply maxillary teeth, alveolar bone, and periodontal tissue via the palatal alveolar foramina with superior alveolar nerves and arteries.<br> Practical Implications. This knowledge is essential for dentists when administering local anesthetic to the maxillary teeth and performing an osteotomy. Anatomic and dental textbooks should be updated with this new knowledge for better patient care. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1939-5981 2025 Study of the Mechanical Properties of Al–Mg ADC6 Aluminum Alloy Produced by Unidirectional Casting Under Various Cooling Rates EN S. Takeuchi M. Okayasu To create the high strength and high ductility of Al–Mg-based aluminum alloy (JIS–ADC6), ADC6 samples were produced by the unidirectional continuous casting (HMC). The HMC process was conducted with direct water cooling to melt ADC6, which can make fine microstructures and control crystal orientation. The cast samples were prepared under various cooling rates (CRs): 6.3, 34, and 62 K/s. The microstructure and crystal orientation of the samples were altered with CR. At CRs of 34 K/s and 62 K/s, the α-Al phases and intermetallic compounds, e.g., Mg2Si and Al15(Fe, Mn)3Si2, became finer and more spherical. The secondary dendrite arm spacing for the sample at 62 K/s was 8.7 µm—more than 70% smaller than the ADC6 sample (ingot) made by a gravity casting process. Notably, at a CR of 34 K/s, the crystal orientation was predominantly arranged with the (101) plane. Tensile properties—ultimate tensile strength (σUTS), 0.2% proof stress (σ0.2), and failure strain (εf)—varied with the CR. The tensile strength (σUTS and σ0.2) consistently increased with increasing the CR. The improvement in the tensile strength resulted from the refined microstructures, such as the α-Al phase and intermetallic compounds. Similarly, the failure strain also increased with increasing CR, which was severely affected by the finer and more spherical intermetallic compounds. In this case, the εf value of the sample at 34 K/s was, however, slightly higher than that at 62 K/s, due to more uniformly organized crystal orientation, while their ductility was much higher than that of the gravity cast sample. The tensile properties in detail were further analyzed using their failure characteristics. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1613-6810 2025 Droplet Transportation on Janus Harp Wires for Enhanced Fog Harvesting e06765 EN Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Taku Ishikawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Ensuring freshwater resources is a vital issue for human beings worldwide. Fog harvesting is one promising way to provide water from unconventional sources. However, clogging by the captured liquid depresses the fog harvesting performance. Here, a harp-shaped Janus harvesting system, which has thin wires with a superhydrophobic side facing the fog stream and a superhydrophilic back side to transport the droplets, is used to yield simultaneous fog capturing and water transport abilities. Attached droplets on the Janus wire transported along the periphery avoided clogging and enhanced the performance. The Janus system thus suppressed the increase and fluctuations of actual shade coefficients, which indicated blockage of the fog stream. This optimized the design of the harvester. Experiments using a multilayered Janus harvester demonstrated a significant enhancement compared with that constructed with mono-wettability wires. Overall, the results indicated the promise of droplet transportation on single wires for improving fog harvesting, as well as for other applications such as oil mist recovery and demulsification. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0952-3480 38 9 2025 Ultrahigh‐Field MR‐Compatible Mechanical Tactile Stimulator for Investigating Somatosensory Processing in Small‐Bodied Animals e70105 EN Chenyu Wang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hirohiko Imai Innovation Research Center for Quantum Medicine, Gifu University School of Medicine Masaki Fukunaga Section of Brain Function Information, National Institute for Physiological Sciences Hiroki Yamamoto Graduate School of Human and Environmental Studies, Kyoto University Yinghua Yu Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazuhiko Seki Department of Neurophysiology, National Center of Neurology and Psychiatry Takashi Hanakawa Department of Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of Medicine Tatsuya Umeda Department of Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of Medicine Jiajia Yang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Common marmosets (Callithrix jacchus), small-bodied New World primates that share similar sensory processing pathways with human beings, have gained great interests. Their small body size allows imaging of brain activity with high spatial resolution and on a whole-brain scale using ultrahigh-field (UHF) magnetic resonance imaging (MRI) scanners. However, the strong magnetic field and the small size of the hand and forearm pose challenges in delivering tactile stimulation during fMRI experiments. In the present study, we developed an MR-compatible tactile dual-point stimulator to provide high-precision mechanical stimulation for exploring somatosensory processing in small-bodied animals. The study population consisted of a water phantom and three male common marmosets. Cerebral blood volume (CBV) weighted fMRI data were obtained with a gradient echo (GE), echo-planar imaging (EPI) sequence at 7T scanner. The output performance of the device was tested by a pressure sensor. The MR compatibility of the device was verified by measuring the temporal signal-to-noise ratio (tSNR) of a water phantom. To test the effectiveness of tactile stimulation, we conducted block designed tactile stimulation experiments on marmosets. A one-way repeated measures ANOVA was conducted for comparing the tSNR results. We performed one-sample t-tests to investigate the negative response of the forearm and hand stimulation with a threshold of t > 1.96 (p < 0.05). Performance tests revealed that mechanical stimulation (averaged force: 31.69 g) was applied with a delay of 12 ms. Phantom experiments confirmed that there was no significant difference in the tSNR among three (10 Hz, 1 Hz, and no-stimulus) conditions (F (2, 798) = 0.71, p = 0.49). The CBV activity results showed that the stimulator successfully elicited hand and forearm somatosensory activations in primary somatosensory areas. These results indicated that the device is well suited for small-bodied animal somatosensory studies. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 0032-5791 104 3 2025 An ultra-simplified protocol for PCR template preparation from both unsporulated and sporulated Eimeria oocysts 104810 EN Aruto Takano Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Dennis V. Umali Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, College April H. Wardhana Research Center for Veterinary Science, National Research and Innovation Agency Dyah H. Sawitri Research Center for Veterinary Science, National Research and Innovation Agency Isao Teramoto Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University Toshimitsu Hatabu Laboratory of Animal Physiology, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yasutoshi Kido Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University Akira Kaneko Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University Kazumi Sasai Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Hiromitsu Katoh Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Makoto Matsubayashi Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Molecular biological techniques have enabled the accurate identification of the avian Eimeria parasite, however, the preparation of PCR template remains a bottleneck due to contaminants from feces and the robust oocyst's wall resistant to chemical and mechanical force. Generally, the preparation of PCR template involves three main steps: (1) pretreatment of oocysts; (2) disruption of oocysts; and (3) purification of genomic DNA. We prepared PCR templates from both unsporulated and sporulated E. tenella oocysts using various protocols, followed by species-specific PCR to define the limit of detection. Our data revealed that whereas neither pretreatment of oocysts with sodium hypochlorite nor purification of genomic DNA with commercial kits improved the limit of detection of PCR, disruption of oocysts was a critical step in the preparation of PCR templates. The most sensitive PCR assay was achieved with the template prepared by disrupting oocysts suspended in distilled water, followed by bead-beating and heating at 99°C for 5 min, which detected 0.16 oocysts per PCR. This ultra-simplified protocol for preparation of PCR template, which does not require expensive reagents or equipment, will significantly enhance the sensitive and efficient molecular identification of Eimeria. It will improve our understanding of the prevalence of this parasite at the species level and contribute to the development of techniques for the control in the field. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2192-2640 14 10 2024 Biocompatibility of Water-Dispersible Pristine Graphene and Graphene Oxide Using a Close-to-Human Animal Model: A Pilot Study on Swine 2401783 EN Paola Nicolussi Istituto Zooprofilattico Sperimentale della Sardegna Giovannantonio Pilo Istituto Zooprofilattico Sperimentale della Sardegna Maria Giovanna Cancedda Istituto Zooprofilattico Sperimentale della Sardegna Guotao Peng Institute of Environmental Medicine, Karolinska Institutet Ngoc Do Quyen Chau CNRS, Immunology, Immunopathology and Therapeutic Chemistry Alejandro De la Cadena Dipartimento di Fisica, Politecnico di Milano Renzo Vanna Istituto di Fotonica e Nanotecnologie – CNR Yarjan Abdul Samad Cambridge Graphene Centre, University of Cambridge Tanweer Ahmed Cambridge Graphene Centre, University of Cambridge Jeremia Marcellino Cambridge Graphene Centre, University of Cambridge Giuseppe Tedde Istituto Zooprofilattico Sperimentale della Sardegna Linda Giro ImmuneNano Laboratory, Department of Biomedical Sciences Acelya Ylmazer Department of Biomedical Engineering, Ankara University Federica Loi Istituto Zooprofilattico Sperimentale della Sardegna Gavina Carta Istituto Zooprofilattico Sperimentale della Sardegna Loredana Secchi Istituto Zooprofilattico Sperimentale della Sardegna Silvia Dei Giudici Istituto Zooprofilattico Sperimentale della Sardegna Simona Macciocu Istituto Zooprofilattico Sperimentale della Sardegna Dario Polli Dipartimento di Fisica, Politecnico di Milano Yuta Nishina Graduate School of Natural Science and Technology, Okayama University Ciriaco Ligios Istituto Zooprofilattico Sperimentale della Sardegna Giulio Cerullo Dipartimento di Fisica, Politecnico di Milano Andrea Ferrari Cambridge Graphene Centre, University of Cambridge Alberto Bianco CNRS, Immunology, Immunopathology and Therapeutic Chemistry Bengt Fadeel Institute of Environmental Medicine, Karolinska Institutet Giulia Franzoni Istituto Zooprofilattico Sperimentale della Sardegna Lucia Gemma Delogu ImmuneNano Laboratory, Department of Biomedical Sciences Graphene-based materials (GBMs) are of considerable interest for biomedical applications, and the pilot study on the toxicological and immunological impact of pristine graphene (GR) and graphene oxide (GO) using swine as a close-to-human provides valuable insights. First, ex vivo experiments are conducted on swine blood cells, then GBMs are injected intraperitoneally (i.p.) into swine. Hematological and biochemical analyses at various intervals indicate that neither GO nor GR cause systemic inflammation, pro-coagulant responses, or renal or hepatic dysfunction. Importantly, no systemic toxicity is observed. Analysis of a panel of 84 immune-related genes shows minimal impact of GO and GR. The animals are sacrificed 21 days post-injection, and transient absorption imaging and Raman mapping show the presence of GO and GR in the mesentery only. Histological evaluation reveals no signs of alterations in other organs. Thus, clusters of both materials are detected in the mesentery, and GO aggregates are surrounded only by macrophages with the formation of granulomas. In contrast, modest local reactions are observed around the GR clusters. Overall, these results reveal that i.p. injection of GBMs resulted in a modest local tissue reaction without systemic toxicity. This study, performed in swine, provides essential guidance for future biomedical applications of graphene. No potential conflict of interest relevant to this article was reported.

Japan Society on Water Environment Acta Medica Okayama 1348-2165 22 6 2024 Effects of Sediment Microbial Fuel Cells on CH4 and CO2 Emissions from Straw Amended Paddy Soil 271 285 EN Adhena Tesfau Bekele Graduate School of Environmental and Life Science, Okayama University Morihiro Maeda Graduate School of Environmental and Life Science, Okayama University Satoshi Akao Faculty of Science and Engineering, Doshisha University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Chiyu Nakano Organization for Research Strategy and Development, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Straw returning into paddy soil enhances soil organic matter which usually promotes the emission of greenhouse gases to the atmosphere. The application of sediment microbial fuel cells (SMFCs) to paddy soil activates power-generating microorganisms and enhances organic matter biodegradation. In the present study, rice straw addition in SMFCs was examined to determine its effect on CH4 and CO2 emissions. Columns (height, 25 cm; inner diameter, 9 cm) with four treatments: soil without and with rice straw under SMFC and without SMFC conditions were incubated at 25°C for 70 days. Anodic potential values at 7 cm depth sediment were kept higher by SMFCs than those without SMFCs. Cumulative CH4 emission was significantly reduced by SMFC with straw amendment (p < 0.05) with no significant effect on CO2 emission. 16S rRNA gene analysis results showed that Firmicutes at the phylum, Closteridiales and Acidobacteriales at order level were dominant on the anode of straw-added SMFC, whereas Methanomicrobiales were in the treatment without SMFC, indicating that a certain group of methanogens were suppressed by SMFC. Our results suggest that the anodic redox environment together with the enrichment of straw-degrading bacteria contributed to a competitive advantage of electrogenesis over methanogenesis in straw-added SMFC system. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2470-1343 9 34 2024 Engineering Zeolitic-Imidazolate-Framework-Derived Mo-Doped Cobalt Phosphide for Efficient OER Catalysts 36114 36121 EN Mohammad Atiqur Rahman Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Ze Cai Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Zannatul Mumtarin Moushumy Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University Ryuta Tagawa Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Yoshiharu Hidaka Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Chiyu Nakano Research Core for Interdisciplinary Sciences, Okayama University Md. Saidul Islam Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Yoshihiro Sekine Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Shintaro Ida Institute of Industrial Nanomaterials (IINa), Kumamoto University Shinya Hayami Institute of Industrial Nanomaterials (IINa), Kumamoto University Designing a cheap, competent, and durable catalyst for the oxygen evolution reaction (OER) is exceedingly necessary for generating oxygen through a water-splitting reaction. In this project, we have designed a ZIF-67-originated molybdenum-doped cobalt phosphide (CoP) using a simplistic dissolution–regrowth method using Na2MoO4 and a subsequent phosphidation process. This leads to the formation of an exceptional hollow nanocage morphology that is useful for enhanced catalytic activity. Metal–organic frameworks, especially ZIF-67, can be used both as a template and as a metal (cobalt) precursor. Molybdenum-doped CoP was fabricated through a two-step synthesis process, and the fabricated Mo-doped CoP showed excellent catalytic activity during the OER with a lower value of overpotential. Furthermore, the effect of the Mo amount on the catalytic activity has been explored. The best catalyst (CoMoP-2) showed an onset potential of around 1.49 V at 10 mA cm–2 to give rise to a Tafel slope of 62.1 mV dec–1. The improved catalytic activity can be attributed to the increased porosity and surface area of the resultant catalyst. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0008-6223 238 2025 Grafting-through functionalization of graphene oxide with cationic polymers for enhanced adsorption of anionic dyes and viruses 120296 EN Ryota Kimura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Pilar Ferré-Pujol Research Core for Interdisciplinary Sciences, Okayama University Yuta Nishina Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Graphene oxide (GO) is a sheet-like carbon material with abundant oxygen-containing functional groups on its surface. GO has been extensively studied as an adsorbent for heavy metals and organic compounds. However, effective strategies for negatively charged materials have yet to be established. This study aimed to synthesize composites of GO and cationic polymers for the selective adsorption of negatively charged materials; a challenge in this approach is the strong electrostatic interactions between GO and cationic polymers, which can lead to aggregation. This study addresses this issue by employing the grafting-through method. GO was initially modified with allylamine to introduce a polymerizable site, followed by radical polymerization to covalently bond polymers to the GO surface, effectively preventing aggregation. Adsorption experiments demonstrated that the GO-polymer composite selectively adsorbs anionic dye, such as methyl orange. Virus adsorption tests showed significantly enhanced performance compared to pristine GO. These results emphasize the critical role of controlled surface modification and charge manipulation in optimizing the adsorption performance of GO. This study establishes a simple and effective approach for synthesizing GO-cationic polymer composites, contributing to the development of advanced materials for water purification applications. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 15 1 2025 OsPIP2;4 aquaporin water channel primarily expressed in roots of rice mediates both water and nonselective Na+ and K+ conductance 12857 EN Sen Thi Huong Tran Institute of Plant Science and Resources, Okayama University Maki Katsuhara Institute of Plant Science and Resources, Okayama University Yunosuke Mito Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University Aya Onishi Institute of Plant Science and Resources, Okayama University Ayaka Higa Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University Shuntaro Ono Institute of Plant Science and Resources, Okayama University Newton Chandra Paul Institute of Plant Science and Resources, Okayama University Rie Horie Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University Yoshihiko Harada Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University Tomoaki Horie Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University Aquaporin (AQP)-dependent water transport across membranes is indispensable in plants. Recent evidence shows that several AQPs, including plasma membrane intrinsic proteins (PIPs), facilitate the electrogenic transport of ions as well as water transport and are referred to as ion-conducting aquaporins (icAQPs). The present study attempted to identify icAQPs that exhibit cation transport activity among PIPs from rice. Electrophysiological experiments on 11 OsPIPs using Xenopus laevis oocytes revealed that OsPIP2;4 mediated the electrogenic transport of alkali monovalent cations with the selectivity sequence of Na+ ≈ K+ > Rb+ > Cs+ > Li+, suggesting non-selective cation conductance for Na+ and K+. Transcripts of OsPIP2;4 were abundant in the elongation and mature zones of roots with similar expression levels between the root stelar and remaining outer parts in the cultivar Nipponbare. Immunostaining using sections of the crown roots of Nipponbare plants revealed the expression of OsPIP2;4 in the exodermis and sclerenchyma of the surface region and in the endodermis and pericycle of the stelar region. The present results provide novel insights into OsPIP2;4-dependent non-selective Na+ and K+ transport and its physiological roles in rice. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0140-7791 2025 Amino Acid Substitutions in Loop C of Arabidopsis PIP2 Aquaporins Alters the Permeability of CO2 EN Shaila Shermin Tania Institute of Plant Science and Resources, Okayama University Shigeko Utsugi Institute of Plant Science and Resources, Okayama University Yoshiyuki Tsuchiya Institute of Plant Science and Resources, Okayama University Shizuka Sasano Institute of Plant Science and Resources, Okayama University Maki Katsuhara Institute of Plant Science and Resources, Okayama University Izumi C. Mori Institute of Plant Science and Resources, Okayama University The transport of CO2 across biomembranes in plant cells is essential for efficient photosynthesis. Some aquaporins capable of CO2 transport, referred to as ‘COOporins’, are postulated to play a crucial role in leaf CO2 diffusion. However, the structural basis of CO2 permeation through aquaporins remains largely unknown. Here, we show that amino acids in loop C are critical for the CO2 permeability of Arabidopsis thaliana PIP2 aquaporins. We found that swapping tyrosine and serine in loop C to histidine and phenylalanine, which differ between AtPIP2;1 and AtPIP2;3, altered CO2 permeability when examined in the Xenopus laevis oocyte heterologous expression system. AlphaFold2 modelling indicated that these substitution induced a conformational shift in the sidechain of arginine in the aromatic/arginine (ar/R) selectivity filter and in lysine at the extracellular mouth of the monomeric pore in PIP2 aquaporins. Our findings demonstrate that distal amino acid substitutions can trigger conformational changes of the ar/R filter in the monomeric pore, modulating CO2 permeability. Additionally, phylogenetic analysis suggested that aquaporins capable of dual water/CO2 permeability are ancestral to those that are water-selective and CO2-impermeable, and CO2-selective and water impermeable. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0033-183X 262 2 2024 Analysis of the effect of permeant solutes on the hydraulic resistance of the plasma membrane in cells of Chara corallina 385 395 EN Masashi Tazawa Yoshida Biological Laboratory Randy Wayne Laboratory of Natural Philosophy, Plant Biology Section, Cornell University Maki Katsuhara Institute of Plant Science and Resources (IPSR), Okayama University In the cells of Chara corallina, permeant monohydric alcohols including methanol, ethanol and 1-propanol increased the hydraulic resistance of the membrane (Lpm−1). We found that the relative value of the hydraulic resistance (rLpm−1) was linearly dependent on the concentration (Cs) of the alcohol. The relationship is expressed in the equation: rLpm−1 = ρmCs + 1, where ρm is the hydraulic resistance modifier coefficient of the membrane. Ye et al. (2004) showed that membrane-permeant glycol ethers also increased Lp−1. We used their data to estimate Lpm−1 and rLpm−1. The values of rLpm−1 fit the above relation we found for alcohols. When we plotted the ρm values of all the permeant alcohols and glycol ethers against their molecular weights (MW), we obtained a linear curve with a slope of 0.014 M−1/MW and with a correlation coefficient of 0.99. We analyzed the influence of the permeant solutes on the relative hydraulic resistance of the membrane (rLpm−1) as a function of the external (π0) and internal (πi) osmotic pressures. The analysis showed that the hydraulic resistance modifier coefficients (ρm) were linearly related to the MW of the permeant solutes with a slope of 0.012 M−1/MW and with a correlation coefficient of 0.84. The linear relationship between the effects of permeating solutes on the hydraulic resistance modifier coefficient (ρm) and the MW can be explained in terms of the effect of the effective osmotic pressure on the hydraulic conductivity of water channels. The result of the analysis suggests that the osmotic pressure and not the size of the permeant solute as proposed by (Ye et al., J Exp Bot 55:449–461, 2004) is the decisive factor in a solute’s influence on hydraulic conductivity. Thus, characean water channels (aquaporins) respond to permeant solutes with essentially the same mechanism as to impermeant solutes. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2574-0962 8 13 2025 Microagglomerate of VO2 Particles Packing Paraffin Wax Using Capillary Force as a Latent Thermal Energy Storage Medium 9595 9603 EN Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kaketo Yamauchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University This study proposed a material to retain paraffin wax with vanadium dioxide (VO2) particles as a latent thermal energy storage medium, an alternative to core–shell microcapsules containing phase change materials. VO2 microparticles, which were synthesized through a sol–gel method and annealing process, were dispersed in the oil-in-water microemulsion to obtain microagglomerates of VO2 microparticles. The average diameter of microagglomerates was 5 μm, and they retained paraffin wax at the vacancies among VO2 particles. Although the microagglomerates had no complete shells similar to core–shell microcapsules, the microagglomerates successfully trapped paraffin wax droplets without any leakage even in a high-temperature environment. It was because capillary forces acting among VO2 particles strictly prevented any leakage of paraffin waxes. The differential scanning calorimetry revealed that the microagglomerates contained only 16.5 wt % of n-octadecane, used as a paraffin wax. However, since VO2 particles can release or absorb latent heat due to their metal–insulator phase transition, the proposed microagglomerates exhibited higher thermal energy storage densities than phase change microcapsules whose shells do not show phase transitions. Moreover, the microagglomerates exhibited higher thermal conductivity than microcapsules with amorphous inorganic shells because the VO2 particles were crystallized through annealing. The proposed microagglomerate is a promising form for further improving the thermal energy storage density and thermal performance of the latent thermal energy storage medium, especially in the temperature range of 30 to 70 °C. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2041-6520 16 26 2025 Collective motions in the primary coordination sphere: a critical functional framework for catalytic activity of the oxygen-evolving complex of photosystem II 12024 EN Hiroshi Isobe Takayoshi Suzuki Research Institute for Interdisciplinary Science, Okayama University Michihiro Suga Research Institute for Interdisciplinary Science, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Okayama University Kizashi Yamaguchi Center for Quantum Information and Quantum Biology, Osaka University Photosynthetic water oxidation, vital for dioxygen production and light energy conversion, is catalyzed by the oxygen-evolving complex of photosystem II, where the inorganic Mn4CaO5 cluster acts as the catalytic core. In this study, we investigate the functional significance of collective motions of amino acid side chains within the primary coordination sphere of the Mn cluster, focusing on their role in modulating the energetic demands for catalytic transformations in the S3 state. We applied regularized canonical correlation analysis to quantitatively correlate the three-dimensional arrangement of coordinating atoms with catalytic driving forces computed via density functional theory. Our analysis reveals that distinct collective side chain motions profoundly influence the energetic requirements for structural reconfigurations of the Mn cluster, achieved through expansion and contraction of the ligand cavity while fine-tuning its geometry to stabilize key intermediates. Complementary predictions from a neural network-based machine learning model indicate that the coordination sphere exerts a variable energetic impact on the catalytic transformations of the Mn cluster, depending on the S-state environment. Integrated computational analyses suggest that the extended lifetime of the S3YZ˙ state, consistently observed after three flash illuminations, may result from slow, progressive protein dynamics that continuously reshape the energy landscape, thereby shifting the equilibrium positions of rapid, reversible chemical processes over time. Overall, our findings demonstrate that collective motions in the primary coordination sphere constitute an active, dynamic framework essential for the efficient execution of multi-electron catalysis under ambient conditions, while simultaneously achieving a high selectivity with irreversible nature required for effective 3O2 evolution. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2079-7737 14 5 2025 Mutagenesis Targeting the S153 Residue Within the Transmembrane β-Hairpin of Mosquito-Larvicidal Mpp46Ab Affects Its Toxicity and the Synergistic Toxicity with Cry4Aa 489 EN Tohru Hayakawa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Syun Yamaoka Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mami Asakura Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Minako Hirano Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toru Ide Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University We constructed a library of Mpp46Ab mutants, in which S153 within the transmembrane β-hairpin was randomly replaced by other amino acids. Mutagenesis and subsequent primary screening yielded 10 different Mpp46Ab mutants in addition to the wild type. Remarkably, S153 was replaced with a more hydrophobic amino acid in most of the mutants, and the S153I mutant in particular exhibited significantly increased toxicity. Electrophysiologic analysis using artificial lipid bilayers revealed that the single-channel conductance and PK/PCl permeability ratio were significantly increased for S153I pores. This suggests that the formation of highly ion-permeable and highly cation-selective toxin pores increases the influx of cations and water into cells, thereby facilitating osmotic shock. In addition, the S153F, S153L, and S153I mutants exhibited significantly reduced synergistic toxicity with Cry4Aa. Electrophysiologic analysis showed that the S153F, S153L, and S153I mutants form toxin pores with a significantly reduced PK/PNa permeability ratio and a significantly increased PK/PCa permeability ratio compared to wild-type pores. Thus, our results suggest that pore formation is central to the insecticidal activity of Mpp46Ab and that the ion permeability of toxin pores is a potential indicator correlated with both toxicity and synergistic toxicity with other toxins. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0039-9140 297 2026 Microfluidic paper-based analytical devices for antioxidant vitamins C and E in foods 128540 EN Mana Kawahara Department of Chemistry, Okayama University Kaewta Danchana Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University In this study, we developed microfluidic paper-based analytical devices (μPADs) for the determination of antioxidant vitamins. The proposed μPADs utilize the reduction of metal ions by hydrophilic and hydrophobic antioxidant vitamins, which is followed by colorimetric reactions with chelating reagents. Hydrophilic vitamin C reduces Fe(III) to Fe(II) and forms a stable Fe(II)-bathophenanthroline complex in an aqueous solution. By contrast, this complex is unstable in organic solvents, and hydrophobic vitamin E requires Fe(III) and bathophenanthroline to be replaced with Cu(II) and bathocuproine. In these results, the relationship between the logarithm of a vitamin's concentration and its color intensity was linear and ranged from 4.4 to 35 mg L−1 for ascorbic acid and 50–200 mg L−1 for α-tocopherol. The limits of detection, estimated from the standard deviation of blank samples, were 3.1 mg L−1 for ascorbic acid and either 27 mg L−1 (in hexane) or 48 mg L−1 (in ethanol) for α-tocopherol. The proposed method was used to quantify vitamin C in bell peppers, mandarin oranges, kiwifruit, and lemons, as well as vitamin E in almonds, almond milk, and dietary supplements. The results demonstrate the effectiveness of these μPADs for the practical analysis of antioxidant vitamins in food samples. No potential conflict of interest relevant to this article was reported.

日本エアロゾル学会 Acta Medica Okayama 0912-2834 40 2 2025 水溶性高分子含有スラリー液滴乾燥過程の評価 99 108 EN Koichi Nakaso Faculty of Environmental, Life, Natural Science and Technology, Okayama University Daichi Yamashita Graduate School of Natural Science and Technology, Okayama University Yutaro Aoyama Graduate School of Natural Science and Technology, Okayama University Yasushi Mino Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kuniaki Gotoh Faculty of Environmental, Life, Natural Science and Technology, Okayama University The granulation process of a slurry droplet containing a water-soluble polymer in a spray dryer is investigated. Although there have been many studies on the drying behavior of a single-component slurry droplet, there have been few reports for a multicomponent slurry droplet. This is due to the complexity and difficulty in evaluating the drying behavior of a multicomponent slurry droplet. Therefore, for the production of granules from multicomponent materials by a spray dryer, its operating conditions are usually determined by trial and error. To optimize the practical granule production process, the drying behavior of multicomponent slurry droplets should be studied. In this study, the drying behavior of a silica slurry droplet containing polyvinyl alcohol (PVA) is investigated. The drying behavior of a droplet suspended on the tip of a needle was observed. The effect of the volume fraction of PVA on the drying behavior and the morphology of a dried granule is studied. The effect of drying condition on the granule formation process is also investigated. As a result, the structure of dried granules was strongly influenced by PVA concentration. Segregation of PVA in the dried granules was observed. Based on the results, the drying process diagram is presented. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0981-9428 227 2025 The hidden cation-selective pore in ion-conducting aquaporin OsPIP2;4 from rice 110168 EN Shuntaro Ono Institute of Plant Science and Resources, Okayama University Sen Thi Huong Tran Institute of Plant Science and Resources, Okayama University Yasunori Saitoh Research Institute for Interdisciplinary Science, Okayama University Shigeko Utsugi Institute of Plant Science and Resources, Okayama University Tomoaki Horie Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University Maki Katsuhara Institute of Plant Science and Resources, Okayama University Ion-conducting aquaporins (icAQPs) transport ions as well as water. Although the molecular mechanism of how AQPs establish selective permeability for water molecules is well understood, the ion-transporting mechanism in icAQPs has not yet been fully elucidated. In this study, we investigated the molecular mechanism of cation transport in OsPIP2;4, an icAQP in rice, by homology modeling and the electrophysiological analysis using Xenopus laevis oocytes. Water and ion transport assays using OsPIP2;4 T227M and G278K mutants strongly suggested that water- and cation-transporting pathways are independent of each other. Data from amino acid substitutions V54I and A143G in OsPIP2;4 led to the identification of a novel hidden pathway for cation transport located on the side surfaces of the tetramer channel, where two protomers are in contact, which is distinct from conventional monomeric pores and the tetrameric central pore in AQPs. Moreover, the present results provide the possibility that this hypothetical hidden pore also functions in the barley icAQP HvPIP2;8. The overall structure of this novel pathway appears to differ from the structure of general cation channels. However, the arrangement of hydrophilic amino acids at the entrance of the pathway of OsPIP2;4 was found to be comparable to that of some cation channels, which implies that the molecular mechanism of dehydration of hydrated ions might resemble that of the channels. Although direct structural evidence is needed to confirm the proposed pathway, the present study can be a stepping stone toward unraveling the mechanism of dual water and ion transport through icAQPs in plants. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2197-4284 12 1 2025 Stability and water solubility of calcium ferrite-type aluminum-rich phase: implications for deep water cycle caused by subducting basaltic crusts 32 EN Xinyue Zhang Deep Space Exploration Laboratory/School of Earth and Space Sciences, University of Science and Technology of China Izumi Mashino Institute for Planetary Materials, Okayama University Takayuki Ishii Institute for Planetary Materials, Okayama University The subducting crustal materials serve as a crucial channel for transporting water to the lower mantle. Recent experimental studies suggest that crustal materials such as basaltic crust can be a main water carrier and reservoir playing an important role on water cycling in the lower mantle. Despite being a primary mineral in crustal materials, the water solubility of calcium ferrite-type (CF) phase and its stability are unclear yet. A recent phase relation study of hydrous basalts showed Na-depletion in lower-mantle minerals, suggesting the presence of fluid possibly with high Na concentration and the absence of CF phase along the low-temperature slab geotherms, where Al-rich hydrous phase H and ferropericlase appear instead. These phases could consequently produce Na-depleted CF phase when reaching the dehydration temperature of Al-rich hydrous phase H. In this study, we investigated the stability and water solubility of CF-type MgAl2O4, which is a main CF component in a hydrous basalt, in water-bearing systems at 26–32 GPa and 1200–1900 °C using a Kawai-type multi-anvil press. Our results indicate that the stability of the CF phase is strongly influenced by water content in the system. Water contents of recovered CF phases estimated by Fourier-transform infrared spectroscopy show a limited variation between 73 and 87 ppm wt at a pressure of 26 GPa and temperatures of 1500–1900 °C. We suggest that CF phase could not be a primary water carrier at lower mantle depths. This emphasizes contributions of hydrous aluminous silica minerals to Earth’s deep water cycling and heterogeneous structures in the lower mantle due to the strong water partitioning to this phase compared with other constituent minerals. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1526-9914 26 6 2025 Quantitative quality control of 3D water tank using image analysis e70119 EN Yuki Tanimoto Department of Radiology, NHO Kure Medical Center and Chugoku Cancer Center Kohei Sugimoto Department of Radiological Technology, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare Kazunobu Koshi Department of Radiology, NHO Fukuyama Medical Center Akira Hiroshige Department of Radiology, NHO Shikoku Cancer Center Shohei Yoshida Department of Radiology, NHO Shikoku Cancer Center Yoshiki Fujita Department of Radiology, NHO Shikoku Cancer Center Atsuki Nakahira Department of Radiology, NHO Shikoku Cancer Center Daiki Nakanishi Division of Radiology, Department of Medical Technology, Kyushu University Hospital Hirofumi Honda Department of Radiological Technology, Ehime University Hospital Masataka Oita Department of Healthcare Science, Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Background and objective: Accurate beam data acquisition using three-dimensional (3D) water tanks is essential for beam commissioning and quality control (QC) in clinical radiation therapy. This study introduces a novel method for quantitative QC of the system, utilizing MV images and webcam videos. The stability of the motor drive speed and the positional accuracy of the fixture were evaluated under two measurement modes: “continuous mode” and “step-by-step mode.”<br> Methods: A TRUFIX mounting system (PTW Freiburg Inc., Germany) was used to attach the center of the steel ball to its top, ensuring alignment with the water surface of the tank. To assess deviations from the radiation isocenter, MV images were acquired and compared with digitally reconstructed radiographs (DRRs). These evaluations were performed at different speed settings (slow, medium, and fast) using ET CT Body Marker (BRAINLAB Inc., USA) mounted on the drive unit. A webcam was utilized to capture the images, and custom-developed tracking software was employed to analyze deviations in driving speed and positional errors.<br> Results: The mean error of the radiation isocenter was 0.37 ± 0.09 mm. As the motor drive speed increased, the discrepancy between the set speed and the actual speed observed in the analysis also became larger. In “continuous mode,” the deviation from the displayed value was greater than that observed in “step-by-step mode.”<br> Conclusion: It is demonstrated that the proposed analysis method can quantitatively evaluate radiation isocenter misalignment, tank setup position deviation, and both the indicated drive speed values and their stability. At higher drive speeds, the “step-by-step mode” showed smaller deviations from the indicated values. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2025 Evaluation of the impacts of climate change on water availability, crop water productivity, and agroclimatic zones in the Tana River Basin, Kenya: a focus on the Bura irrigation scheme EN DANIEL MWENDWA WAMBUA Graduate School of Environmental and Life Science, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2025 Molecular Simulation and Integral Equation Studies of the Solute-Solute Effective Interactions in Water and Simple Liquids EN Hidefumi NAITO Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0039-9140 295 2025 Using a microfluidic paper-based analytical device and solid-phase extraction to determine phosphate concentration 128303 EN Kaewta Danchana Department of Chemistry, Okayama University Haruka Namba Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University Phosphate is an essential nutrient, but in high concentrations it contributes to water pollution. Traditional methods for phosphate measurement, such as absorption spectrophotometry and ion chromatography, require expensive equipment and skilled operators. This study introduces a microfluidic paper-based analytical device (μPAD) that is designed to accomplish field-based, low-concentration phosphate measurements. This μPAD utilizes colorimetric detection based on the molybdenum blue method. Herein, we describe how the conditions were optimized in terms of design and sensitivity by adjusting reagent concentrations, paper thickness, and the time frames for sample introduction, and reaction. The operation consists of simply dipping the μPAD into a sample, capturing images in a home-made photo studio box, and processing the images with ImageJ software to measure RGB intensity. An additional preconcentration step involves solid-phase extraction with an anion exchange resin that achieves a 10-fold enrichment, which enables detection that ranges from 0.05 to 1 mg L−1 with a detection limit of 0.089 mg L−1 and a quantification limit of 0.269 mg L−1. The replicated measurements showed good reproducibility both intraday and interday (five different days) as 4.7 % and 3.0 % of relative standard deviations, respectively. After storage in a refrigerator for as long as 26 days, this μPAD delivered stable and accurate results for real-world samples of natural water, soil, and toothpaste. The results produced using this system correlate well with those produced via spectrophotometry. This μPAD-based method is a cost-effective, portable, rapid, and simple approach that allows relatively unskilled operators to monitor phosphate concentrations in field applications. No potential conflict of interest relevant to this article was reported.

Spandidos Publications Acta Medica Okayama 2049-9434 22 6 2025 Effects of aged garlic extract on experimental periodontitis in mice 97 EN Canyan Kuang Department of Pathophysiology‑Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Anna Hirai Division of Periodontics and Endodontics, Department of Dentistry, Okayama University Hospital Chiaki Kamei‑Νagata Division of Periodontics and Endodontics, Department of Dentistry, Okayama University Hospital Hiroshi Nango Central Research Institute, Wakunaga Pharmaceutical Co., Ltd. Masahiro Ohtani Central Research Institute, Wakunaga Pharmaceutical Co., Ltd. Kazuhiro Omori Department of Pathophysiology‑Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shogo Takashiba Department of Pathophysiology‑Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Aged garlic extract (AGE) has been reported to exert anti‑inflammatory effects. AGE has been recently found to reduce the inflammatory symptoms of periodontitis, a widespread chronic inflammatory disease caused by oral bacterial infection. However, the mechanisms underlying these effects remain unclear. In the present study, it was aimed to determine the effects of AGE on experimental periodontitis and the related inflammatory factors. AGE (2 g/kg/day) was orally administered to 15 mice during the experimental period, while a control group consisted of 15 mice that received pure water. A total of 3 days after initiation of administration, the left maxillary second molar was ligated with a 5‑0 silk thread for 7 days. Blood biochemical tests were performed to monitor the systemic effects of AGE. Alveolar bone loss was measured morphometrically using a stereomicroscope, and reverse transcription‑quantitative PCR was performed to assay mRNAs of proinflammatory cytokines in gingival tissues. A histological survey was also performed to identify osteoclasts in periodontitis lesions (five mice per group). The total protein and albumin levels showed no significant differences between the AGE and control groups. However, ligation‑induced bone resorption was lower in the AGE group than in the control group (P=0.01). Additionally, ligature increased the mRNA expression of inflammatory cytokines, whereas AGE administration tended to suppress them. Remarkably, tumor necrosis factor gene expression was significantly suppressed (P=0.04). The number of osteoclasts in periodontitis lesions was reduced in the AGE‑treated group. These results indicate that AGE prevents alveolar bone loss by suppressing the inflammatory responses related to osteoclast differentiation in the periodontal tissue. Further research is needed to elucidate the role of AGE in reducing inflammatory bone resorption. No potential conflict of interest relevant to this article was reported.

Japan Society of Hydrology and Water Resources Acta Medica Okayama 1882-3416 19 2 2025 Effects of different management approaches on unmet water demand in coffee-producing areas during wet and dry years: a case study of the Srepok River Watershed, Vietnam 94 100 EN Truong Thao Sam Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University The primary cause of conflicts over water allocation is growing demand and limited supply, which has become an increasingly serious issue in many watersheds. To alleviate water disputes, effective management strategies can be employed, particularly in the context of intensifying agricultural production and unpredictable changes in weather. In this study, two models, SWAT and WEAP, and the modified surface water supply index (MSWSI) were utilized to evaluate water allocation in the Srepok River Watershed (SRW), considering the prioritization of demand and various irrigation methods, during both wet and dry years. The crop irrigation was chosen to be the main focus in relation to the unmet water demand (UWD). The results indicated that coffee was the primary cause of UWD in the middle of the watershed during the second half of the dry season, and annual crops (AC) were the secondary cause. This research further elucidated that while prioritizing demand had an insignificant impact, transitioning from hose irrigation to sprinkler irrigation could be remarkably effective in mitigating the issues of UWD in coffee crops during both wet and dry years. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1996-1944 18 9 2025 Initial Bonding Performance to CAD/CAM Restorative Materials: The Impact of Stepwise Concentration Variation in 8-Methacryloxyoctyl Trimethoxy Silane and 3-Methacryloxypropyl Trimethoxy Silane on Feldspathic Ceramic, Lithium Disilicate Glass-Ceramic, and Polymer-Infiltrated Ceramic 1983 EN Yukinori Maruo Department of Prosthodontics, Okayama University Miho Kuwahara Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kumiko Yoshihara Health Research Institute, National Institute of Advanced Industrial Science and Technology Masao Irie Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School Mai Yoshizane Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takuya Matsumoto Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kentaro Akiyama Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences This study investigated the effects of varying concentrations of two distinct silane agents, 8-methacryloxyoctyl trimethoxy silane (8-MOTS) and 3-methacryloxypropyl trimethoxy silane (γ-MPTS), on their initial bonding efficacy to feldspathic ceramic (FC), lithium disilicate glass-ceramic (LD) and polymer-infiltrated ceramic (PIC) specimens, in 10% increments for concentrations ranging from 10% to 40%. Shear bond strengths between the ceramic substrates and the luting material were assessed following 24 h incubation in distilled water. For FC, the median value of shear bond strength peaked at 20% of γ-MPTS (7.4 MPa), while 8-MOTS exhibited a concentration-dependent increase, reaching its highest value at 40% (13.1 MPa). For LD, γ-MPTS above 10% yielded similar strength median values (10.2 MPa), whereas 8-MOTS at 30% (15.8 MPa) and 40% (13.4 MPa) yielded higher strength values than at 10% (2.9 MPa) and 20% (4.1 MPa), with the highest median value exhibited at 30%. For PIC, both γ-MPTS and 8-MOTS demonstrated similarly low bond strength values which were not significantly different from the non-silane-treated specimens. When applied on silica-based FC and LD, silane revealed a concentration-dependent bonding effect, with 8-MOTS exhibiting superior bond strength to γ-MPTS. However, PIC, characterized by a high inorganic filler content, demonstrated limited bondability with both silanes. No potential conflict of interest relevant to this article was reported.

Informa UK Limited Acta Medica Okayama 0737-3937 43 6 2025 Spray-drying of polymer solutions across a broad concentration range and the subsequent formation of a few micro- ∼nano-meter sized fibers 1108 1116 EN Chika Araga Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Kaito Fukushima Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Haruna Sato Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Nao Honda Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Takato Hasegawa Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Koichi Nakaso Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Naoyuki Ishida Department of Chemical Engineering and Material Sciences, Faculty of Science and Engineering, Doshisha University Koreyoshi Imamura Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Spray drying is a widely utilized technique for the concentration and fine particulation of dried products. This study demonstrated that a versatile spray dryer, equipped with a two-fluid nozzle atomizer, can convert polymer solutions into nanoscale fibers by manipulating the conditions of the polymer solutions. The polymers employed in this research included polyvinylpyrrolidones (Mw 24.5 k to 60 kDa), dextrans (70 k to 450–650 kDa), pullulan, gum Arabic, Eudragit and agar, with methanol and water serving as solvents. Various combinations of polymers and solvents were subjected to spray drying at polymer concentrations ranging from 5 to 1000 g/L. Scanning electron microscopy analyses of the spray-dried samples indicated that the products transitioned from micrometer-sized particles to sub-micrometer fibers in several instances when the polymer concentrations exceeded specific threshold levels. The investigation also explored the relationship between these threshold concentrations and the surface tension and viscosity of the polymer solutions. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 79 2 2025 Association between the Pretreatment Body Mass Index and Anamorelin’s Efficacy in Patients with Cancer Cachexia: A Retrospective Cohort Study 65 73 EN Masatoshi Maki Department of Hospital Pharmacy, NHO Fukuyama Medical Center Ryo Takada Department of Hospital Pharmacy, NHO Fukuyama Medical Center Tomoyuki Ishigo Department of Pharmacy, Sapporo Medical University Hospital Miki Fujiwara Department of Hospital Pharmacy, NHO Fukuyama Medical Center Yoko Takahashi Department of Hospital Pharmacy, NHO Fukuyama Medical Center Shinya Otsuka Department of Surgery, NHO Fukuyama Medical Center Koji Tamura Department of Hospital Pharmacy, NHO Fukuyama Medical Center Terutaka Hamaoka Department of Hospital Pharmacy, NHO Fukuyama Medical Center Original Article 10.18926/AMO/68644 Anamorelin (ANAM) is used to treat cancer-associated cachexia, a syndrome involving muscle loss and anorexia. The timing of the initiation of ANAM treatment is crucial to its efficacy. Although the body mass index (BMI) is a diagnostic criterion for cancer cachexia, no studies have explored its association with ANAM efficacy. We conducted a single-center, retrospective cohort study to investigate the association between the pre-treatment BMI and ANAM efficacy in patients with cancer-associated cachexia (n=47). The ANAM treatment was considered effective if the patient’s appetite improved within 30 days of treatment initiation. We calculated a BMI cutoff value (19.5 kg/m2) and used it to divide the patients into high- and low-BMI groups. Their background, clinical laboratory values, cancer types, and treatment lines were investigated. Twenty (42.6%) had a high BMI (≥ 19.5 kg/m2) and 27 (57.4%) had a low BMI (< 19.5 kg/m2). High BMI was significantly associated with ANAM effectiveness (odds ratio 7.86, 95% confidence interval 1.99-31.00, p=0.003). Together these results indicate that it is beneficial to initiate ANAM treatment before a patient’s BMI drops below 19.5 kg/m2. Our findings will help advance cancer cachexia treatment and serve as a reference for clinicians to predict ANAM’s efficacy. No potential conflict of interest relevant to this article was reported.

BMC Acta Medica Okayama 1477-7819 23 1 2025 Surgical protocol of robotic liver resection using a two-surgeon technique (TAKUMI-3): a technical note and initial outcomes 124 EN Kosei Takagi Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Tomokazu Fuji Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Kazuya Yasui Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Yuzo Umeda Department of Hepatobiliary Pancreatic Surgery, Ehime University Graduate School of Medicine Motohiko Yamada Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Takeyoshi Nishiyama Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Yasuo Nagai Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Noriyuki Kanehira Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Background Internationally, evidence supporting robotic liver resection (RLR) has gradually increased in recent years. However, a standardized protocol for RLR remains lacking. This study describes a surgical protocol and the initial outcomes of RLR in a high-volume center for robotic hepatopancreatobiliary surgery in Japan.<br> Methods Patients were placed in the reverse Trendelenburg position, with a supine position for anterolateral tumors and left lateral position for posterosuperior tumors. Our standard RLR protocol involved a two-surgeon technique. Liver parenchymal transection was performed by an assistant using the clamp crush technique with a console, with or without a laparoscopic Cavitron ultrasonic surgical aspirator (CUSA). Surgical techniques, including the tips, tricks, and pitfalls of RLR, are also demonstrated.<br> Results We performed 113 RLR at our institution for common primary diseases, including hepatocellular carcinoma (n = 52, 46.0%) and metastatic tumors (n = 48, 42.5%) between July 2022 and December 2024. The median operative time and estimated blood loss were 156 min (interquartile range [IQR], 121-209 min) and 20 mL (IQR, 0-100 mL), respectively. During liver parenchymal transection, a laparoscopic CUSA was used in 59 patients (52.2%), and a water-jet scalpel was used in 12 patients (10.6%). The incidence of mortality, major complications, and bile leakage was 0%, 6.2%, and 2.7%, respectively. The median hospital stay was 7 days (IQR, 6-9 days).<br> Conclusions We successfully introduced an RLR program using the two-surgeon technique. Safe implementation of RLR can be achieved upon completion of the training program and thorough understanding of the surgical protocols. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2227-9032 13 6 2025 Effects of Trehalose on Halitosis: A Randomized Cross-Over Clinical Trial 619 EN Hisataka Miyai Department of Preventive Dentistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takaaki Tomofuji Department of Community Oral Health, School of Dentistry, Asahi University Hirofumi Mizuno Department of Preventive Dentistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Manabu Morita Department of Oral Health Sciences, Faculty of Health Care Sciences, Takarazuka University of Medical and Health Care Momoko Nakahara Department of Preventive Dentistry, Division of Dentistry, Okayama University Hospital Kota Kataoka Department of Preventive Dentistry, Division of Dentistry, Okayama University Hospital Ichiro Sumita Department of Preventive Dentistry, Division of Dentistry, Okayama University Hospital Yurika Uchida Department of Preventive Dentistry, Division of Dentistry, Okayama University Hospital Naoki Toyama Department of Preventive Dentistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Aya Yokoi Department of Preventive Dentistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Reiko Yamanaka-Kohno Department of Preventive Dentistry, Division of Dentistry, Okayama University Hospital Noriko Takeuchi Department of Preventive Dentistry, Division of Dentistry, Okayama University Hospital Takayuki Maruyama Department of Preventive Dentistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Daisuke Ekuni Department of Preventive Dentistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background/Objectives: Halitosis is a condition characterized by an unpleasant malodor. Intra-oral halitosis is caused by volatile sulfur compounds (VSCs) and can be associated with oral dryness. Trehalose is one of the materials used to relieve oral dryness. The aim of the present study was to investigate the effect of trehalose on halitosis. Methods: This prospective, double-blinded, placebo-controlled, cross-over study enrolled volunteers from Okayama University Hospital. The participants were randomly divided into two groups, with one group receiving trehalose (a 10% trehalose solution) and the other receiving a placebo (distilled water) in a 1:1 allocation. The primary study outcome was the subjective organoleptic test. The secondary outcomes were the concentrations of the VSCs, which were measured using a portable gas chromatography device, and the oral moisture status, which was measured using an oral moisture meter. The planned sample size was 10 participants based on the previous study. Results: The final intention-to-treat analysis was performed using the data from 9 participants. After applying 10% trehalose as an oral spray, the organoleptic score decreased in a time-dependent manner. However, no significant differences were seen between the trehalose and placebo groups. In terms of secondary outcomes, the oral moisture levels increased immediately after the trehalose spray application, and significant differences in the amount of change from the baseline were seen between the trehalose and placebo groups (p = 0.047). No significant differences were seen in any of the other variables (p > 0.05). Conclusions: We could not identify any positive effects on halitosis from a one-time 10% trehalose application as an oral spray in this prospective, double-blinded, placebo-controlled, cross-over study. However, the trehalose application immediately improved the oral moisture levels and was useful for treating oral dryness. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 41 11 2025 Droplet Impact Behavior on Convex Surfaces with a Circumferential Wettability Difference 7640 7647 EN Taku Ishikawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Controlling the bouncing behavior of the impacting droplets is an important issue for splay cooling, icing prevention, and other applications. The bouncing behavior of impacting droplets on superhydrophobic curved surfaces and flat substrates with a wettability difference has been widely investigated, and droplets impacting these surfaces show shorter contact times than those on superhydrophobic flat surfaces and droplet transport. However, there have been few studies on the droplet impact behavior on curved surfaces with a wettability difference, where efficient droplet control could be achieved by combining the features. In the present study, droplet impact experiments were conducted using copper cylinders with different circumferential wettabilities from hydrophilic to superhydrophobic, varying the impact velocity, cylinder diameter, and rotation angle. Droplets that impacted the wettability boundary showed asymmetric deformation and moved to the hydrophilic side, owing to the driving force of the wettability difference. Moreover, the droplet behavior was classified into four types: the droplet bounced off the surface, the droplet bounced off the surface and split, the droplet attached to the surface, and the droplet attached to the surface and split. The droplet behavior was estimated by using the maximum spreading width of the droplet impacted on the flat substrate. We evaluated whether the droplets attached to the surface or bounced off the surface after impact using the Weber number and rotation angle, and the estimations were in agreement with the experimental results for cylinder diameters of 4 and 6 mm. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0026-265X 210 2025 A microfluidic paper-based analytical device that uses gelatin film to assay protease activity via time readout 112952 EN Jianchao Ren Department of Chemistry, Okayama University Kaewta Danchana Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University Food processing, detergents, and pharmaceuticals frequently employ proteases, which are enzymes that break the chemical bonds of both proteins and peptides. In this work, we developed a microfluidic paper-based analytical device (µPAD) for protease activity assays via time readout. To accomplish this, we folded the µPAD to form layers, then inserted a water-insoluble gelatin film between the layers of paper to form the device. Lamination helps to maintain the gelatin film between the introduction zone, which is the upper layer, and the detection channel, which is the lower layer. Proteases decompose the gelatin film when it enters the introduction zone, which then allows it to flow into the detection channel. The protease activity in the sample solution determines the time required to dissolve the gelatin film, which leads to a linear relationship between the logarithm of the protease concentration and the time required to flow the solution a specific distance on the detection channel. The µPAD was used to measure proteases in concentrations that ranged from 0.25 to 1 mg L−1 for bromelain, 2.5 to 10 mg L−1 for papain, and 1 to 8 mg L−1 for trypsin. The limits of quantification for bromelain, papain, and trypsin were 0.41, 2.7, and 9.2 mg mL−1, respectively. The relative standard deviations for bromelain were smaller than 2 % for concentrations ranging from 0.5 to 1.0 mg L−1. We compared the µPAD to a commercially available protease activity assay kit, which relies on quenching fluorescein isothiocyanate-labeled casein. Both methods demonstrated the same order of activity: bromelain > papain > trypsin. The proposed device allowed the assay of bromelain in both pineapple pulp and juice, which were stored at room temperature. When first using the proposed device, the bromelain in the pulp gradually lost its activity, while the activity of the bromelain in the juice showed no significant change for five days. The µPAD requires no analytical instruments for quality control and monitoring of the protease activity in food. No potential conflict of interest relevant to this article was reported.

Japan Society of Hydrology and Water Resources Acta Medica Okayama 1882-3416 19 1 2025 Evaluation of the temporal behavior of fulvic acid iron in Asahi River, Okayama, Japan 36 43 EN Rohdof Lactem Yengeh Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University Yasushi Mori Graduate School of Environmental and Life Science, Okayama University Morihiro Maeda Graduate School of Environmental and Life Science, Okayama University Iron is essential for biogeochemical processes in aquatic ecosystems, but its riverine concentration can be affected by environmental conditions. This study assessed weekly fulvic acid iron (FAFe) concentration at a single sampling site in Asahi River from 2022–2023 to explore the differences in the temporal scales. The objectives of this study were to evaluate the effects of physicochemical properties of the river on the concentration of FAFe, analyze the concentration of FAFe in spring, summer, autumn and winter, and assess the relationship between FAFe concentration and land use types of the watershed. The results indicated that physicochemical parameters, such as pH and surface water temperature (SWT) seemed to influence FAFe concentration (p < 0.05). Hydrological dynamics influenced FAFe concentration and transport, revealing an increasing trend during spring (p < 0.001) and summer (p = 0.05), with non-significant trends during autumn and winter (p > 0.05). FAFe exhibited a strong positive correlation with total organic carbon (TOC) (p < 0.001). Upland fields significantly influenced FAFe concentration (p < 0.01) through runoff with abundant NO3– and PO43– into the river. Thus, FAFe concentration in Asahi River was influenced by pH, SWT, TOC, hydrological regime, and agricultural runoff. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2073-445X 14 2 2025 Interchangeability of Cross-Platform Orthophotographic and LiDAR Data in DeepLabV3+-Based Land Cover Classification Method 217 EN Shijun Pan Graduate School of Environmental and Life Science, Okayama University Keisuke Yoshida Graduate School of Environmental and Life Science, Okayama University Satoshi Nishiyama Graduate School of Environmental and Life Science, Okayama University Takashi Kojima TOKEN C. E. E. Consultants Co., Ltd. Yutaro Hashimoto Graduate School of Environmental and Life Science, Okayama University Riverine environmental information includes important data to collect, and the data collection still requires personnel's field surveys. These on-site tasks still face significant limitations (i.e., hard or danger to entry). In recent years, as one of the efficient approaches for data collection, air-vehicle-based Light Detection and Ranging technologies have already been applied in global environmental research, i.e., land cover classification (LCC) or environmental monitoring. For this study, the authors specifically focused on seven types of LCC (i.e., bamboo, tree, grass, bare ground, water, road, and clutter) that can be parameterized for flood simulation. A validated airborne LiDAR bathymetry system (ALB) and a UAV-borne green LiDAR System (GLS) were applied in this study for cross-platform analysis of LCC. Furthermore, LiDAR data were visualized using high-contrast color scales to improve the accuracy of land cover classification methods through image fusion techniques. If high-resolution aerial imagery is available, then it must be downscaled to match the resolution of low-resolution point clouds. Cross-platform data interchangeability was assessed by comparing the interchangeability, which measures the absolute difference in overall accuracy (OA) or macro-F1 by comparing the cross-platform interchangeability. It is noteworthy that relying solely on aerial photographs is inadequate for achieving precise labeling, particularly under limited sunlight conditions that can lead to misclassification. In such cases, LiDAR plays a crucial role in facilitating target recognition. All the approaches (i.e., low-resolution digital imagery, LiDAR-derived imagery and image fusion) present results of over 0.65 OA and of around 0.6 macro-F1. The authors found that the vegetation (bamboo, tree, grass) and road species have comparatively better performance compared with clutter and bare ground species. Given the stated conditions, differences in the species derived from different years (ALB from year 2017 and GLS from year 2020) are the main reason. Because the identification of clutter species includes all the items except for the relative species in this research, RGB-based features of the clutter species cannot be substituted easily because of the 3-year gap compared with other species. Derived from on-site reconstruction, the bare ground species also has a further color change between ALB and GLS that leads to decreased interchangeability. In the case of individual species, without considering seasons and platforms, image fusion can classify bamboo and trees with higher F1 scores compared to low-resolution digital imagery and LiDAR-derived imagery, which has especially proved the cross-platform interchangeability in the high vegetation types. In recent years, high-resolution photography (UAV), high-precision LiDAR measurement (ALB, GLS), and satellite imagery have been used. LiDAR measurement equipment is expensive, and measurement opportunities are limited. Based on this, it would be desirable if ALB and GLS could be continuously classified by Artificial Intelligence, and in this study, the authors investigated such data interchangeability. A unique and crucial aspect of this study is exploring the interchangeability of land cover classification models across different LiDAR platforms. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2078-2489 16 2 2025 Implementation of Sensor Input Setup Assistance Service Using Generative AI for SEMAR IoT Application Server Platform 108 EN I. Nyoman Darma Kotama Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Yohanes Yohanie Fridelin Panduman Graduate School of Natural Science and Technology, Okayama University Komang Candra Brata Graduate School of Natural Science and Technology, Okayama University Anak Agung Surya Pradhana Graduate School of Natural Science and Technology, Okayama University Noprianto Graduate School of Natural Science and Technology, Okayama University I. Gusti Made Ngurah Desnanjaya Department of Computer System Engineering, Institute of Business and Technology Indonesia For rapid deployments of various IoT application systems, we have developed Smart Environmental Monitoring and Analytical in Real-Time (SEMAR) as an integrated server platform. It is equipped with rich functions for collecting, analyzing, and visualizing various data. Unfortunately, the proper configuration of SEMAR with a variety of IoT devices can be complex and challenging for novice users, since it often requires technical expertise. The assistance of Generative AI can be helpful to solve this drawback. In this paper, we present an implementation of a sensor input setup assistance service for SEMAR using prompt engineering techniques and Generative AI. A user needs to define the requirement specifications and environments of the IoT application system for sensor inputs, and give them to the service. Then, the service provides step-by-step guidance on sensor connections, communicating board configurations, network connections, and communication protocols to the user, which can help the user easily set up the configuration to connect the relevant devices to SEMAR. For evaluations, we applied the proposal to the input sensor setup processes of three practical IoT application systems with SEMAR, namely, a smart light, water heater, and room temperature monitoring system. In addition, we applied it to the setup process of an IoT application system for a course for undergraduate students at the Insitut Bisnis dan Teknologi (INSTIKI), Indonesia. The results demonstrate the effectiveness of the proposed service for SEMAR. No potential conflict of interest relevant to this article was reported.

Japanese Society of Animal Breeding and Genetics Acta Medica Okayama 1345-9961 53 1 2025 Investigation of SNPs associated with reproductive and body growth traits in Vietnamese and Nepalese native buffaloes 3 10 EN Nguyen Thuy Thanh Graduate School of Environmental and Life Science, Okayama University Tetsuo Kunieda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shah Manoj Kumar National Swine Research Program Le Thu Nu Anh Faculty of Animal Sciences and Veterinary Medicine, University of Agriculture and Forestry, Hue University Nguyen Van Huu Faculty of Animal Sciences and Veterinary Medicine, University of Agriculture and Forestry, Hue University Koichiro Ushijima Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mayuko Nagae Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takehito Tsuji Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Water buffaloes are essential to the rural economies of many developing countries, including Vietnam and Nepal, but native buffalo populations in these countries face challenges such as low productivity due to fertility and body growth issues. This study analyzed 34 SNPs in 18 genes associated with reproductive and body growth traits reported in cattle and buffalo in Vietnamese and Nepalese native buffaloes. Results showed no polymorphism at bovine SNPs in either buffalo. Further analysis with SNPs previously reported only in popular buffalo breeds, such as Murrah, found that Vietnamese buffalo were monomorphic at all sites, which may reflect reduced genetic diversity due to population decline. In contrast, Nepalese buffalo, consisting of two native breeds, showed polymorphism in 11 SNPs in 7 genes, with 10 of these matching those found in the Murrah buffalo analyzed here. These findings suggest that these SNPs may be applicable for genetic improvement in Nepalese native buffalo. This study provides valuable insights for future conservation and breeding programs aimed at enhancing reproductive and body growth performance of native buffalo in Vietnam and Nepal. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2025 1 2024 Modification on Thermal Motion in Geant4 for Neutron Capture Simulation in Gadolinium Loaded Water 013C01 EN Y. Hino Department of Physics, Okayama University K. Abe Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo R. Asaka Department of Physics, Faculty of Science and Technology, Tokyo University of Science S. Han Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo M. Harada Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo M. Ishitsuka Department of Physics, Faculty of Science and Technology, Tokyo University of Science H. Ito Department of Physics, Faculty of Science and Technology, Tokyo University of Science S. Izumiyama Department of Physics, Tokyo Institute of Technology Y. Kanemura Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo Y. Koshio Department of Physics, Okayama University F. Nakanishi Department of Physics, Okayama University H. Sekiya Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo T. Yano Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo Neutron tagging is a fundamental technique for electron anti-neutrino detection via the inverse beta decay channel. A reported discrepancy in neutron detection efficiency between observational data and simulation predictions prompted an investigation into neutron capture modeling in Geant4. The study revealed that an overestimation of the thermal motion of hydrogen atoms in Geant4 impacts the fraction of captured nuclei. By manually modifying the Geant4 implementation, the simulation results align with calculations based on evaluated nuclear data and show good agreement with observables derived from the SK-Gd data. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0008-6223 234 2025 Reversible chemical modifications of graphene oxide for enhanced viral capture and release in water 120015 EN Pilar Ferré-Pujol Research Institute for Interdisciplinary Science, Okayama University Seiji Obata Research Institute for Interdisciplinary Science, Okayama University Jésus Raya Institut de Chimie, UMR 7177 CNRS, Université de Strasbourg Alberto Bianco Research Institute for Interdisciplinary Science, Okayama University Hiroyuki Katayama Department of Urban Engineering, School of Engineering, The University of Tokyo Takashi Kato Research Center for Water Environment Technology, School of Engineering, The University of Tokyo Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Detecting low concentrations of viruses in sewage water is crucial for monitoring the spread of emerging viral diseases. However, current detection methods, which involve concentrating viruses using traditional materials such as gauze or cotton, have limitations in effectively accomplishing this task. This study demonstrates that graphene oxide (GO), a two-dimensional carbon material, possesses strong viral adsorption capabilities. However, it lacks efficiency for effective viral release. Therefore, we designed a series of new GO-based materials, which exhibited a viral adsorption similar to pristine GO, while significantly enhancing their release performance by attaching alkyl chains and hydrophilic functional groups. Among the synthesized materials, 1,8-aminooctanol grafted to GO (GO-NH2C8OH) has emerged as the most promising candidate, achieving a viral release rate higher than 50 %. This superior performance can be attributed to the synergistic effect of the alkyl chain and the terminal OH group, which enhances both its affinity for viruses and water dispersibility. Furthermore, we have successfully applied GO-NH2C8OH in a new protocol for concentrating viruses from sewage wastewater. This approach has demonstrated a 200-fold increase in virus concentration, allowing PCR detection of this type of pathogens present in wastewater below the detection limit by direct analysis, underscoring its significant potential for virus surveillance. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1618-954X 2024 The perception of plastic waste and composition of boathouse waste in floating villages on Tonlé Sap Lake, Cambodia EN Habuer Environmental Management Course, Architecture, Civil Engineering and Environmental Management Program, School of Engineering, Okayama University Takeshi Fujiwara Environmental Management Course, Architecture, Civil Engineering and Environmental Management Program, School of Engineering, Okayama University Spoann Vin Department of Economic Development, Faculty of Development Studies, Royal University of Phnom Penh Phat Chandara Department of Natural Resource Management and Development, Faculty of Development Studies, Royal University of Phnom Penh Makoto Tsukiji Environmental Management Course, Architecture, Civil Engineering and Environmental Management Program, School of Engineering, Okayama University Villagers living on Tonlé Sap (TS) Lake have low incomes and no access to basic public services, such as waste management, domestic water, electricity, and health care. Knowledge of the villagers’ perceptions and the composition of the waste from their boathouses will contribute to constructing a waste collection system with community participation within the framework of waste prevention and reduction. This study surveyed residents living in boathouses in four floating villages on TS Lake, Cambodia, regarding their perceptions and boathouse waste composition to assess the status of plastic waste and the villagers’ environmental awareness and their willingness to participate in waste collection. The household waste survey sought to clarify the amount of plastic waste and other recyclable waste discharged from floating houses. The perception survey revealed that in the wet season, 36% of respondents disposed of plastic waste by open burning/dumping and 40% by discharge into TS Lake; in the dry season, 76% disposed of waste by open burning/dumping, and only 4% discharged waste into TS Lake. An analysis of the boathouse plastic waste composition showed that residents of the floating villages generated 40.21 g plastic waste/day/capita, which was much lower than 340 g/day/capita in the USA, 120 g/day/capita in China, and even 70 g/day/capita in Cambodian on average, but higher than the 10 g/day/capita in India. This study proposes a novel and valuable framework to estimate and determine the level of awareness of people in floating villages related to plastic pollution effects and waste components from boathouses. At the same time, the research results provide an essential scientific basis to be able to develop an effective waste collection system in the area of TS Lake. The proposed framework of this study will help the policy decision-makers in the TS Lake area and those in similar geographical regions facing similar problems. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1520-6106 129 2 2024 Hydronium Ions Are Less Excluded from Hydrophobic Polymer–Water Interfaces than Hydroxide Ions 726 735 EN Ryan L. Myers Department of Chemistry, The Pennsylvania State University, University Park Aoi Taira Department of Chemistry, Okayama University Chuanyu Yan Department of Chemistry, The Pennsylvania State University, University Park Seung-Yi Lee Department of Chemistry, The Pennsylvania State University, University Park Lauren K. Welsh Department of Chemistry, The Pennsylvania State University, University Park Patrick R. Ianiro Department of Chemistry, University of Pittsburgh at Bradford Tinglu Yang Department of Chemistry, The Pennsylvania State University, University Park Kenichiro Koga Department of Chemistry, Okayama University Paul S. Cremer Department of Chemistry, The Pennsylvania State University, University Park The cloud point temperatures of aqueous poly(N-isopropylacrylamide) (PNIPAM) and poly(ethylene) oxide (PEO) solutions were measured from pH 1.0 to pH 13.0 at a constant ionic strength of 100 mM. This ionic strength was reached by mixing the appropriate concentration of NaCl with either HCl or NaOH. The phase transition temperature of both polymers was nearly constant between pH 2.0 and 12.0. However, the introduction of 100 mM HCl (pH 1.0) led to an increase in the cloud point temperature, although this value was still lower than the cloud point temperature in the absence of salt. By contrast, the introduction of 100 mM NaOH (pH 13.0) caused a decrease in the cloud point temperature, both relative to adding 100 mM NaCl and adding no salt. Nuclear magnetic resonance (NMR) studies of these systems were performed below the cloud point temperature, and the chemical shifts closely tracked the corresponding changes in the phase transition temperature. Specifically, the introduction of 100 mM HCl caused the 1H chemical shift to move downfield for the CH resonances from both PNIPAM and PEO, while 100 mM NaOH caused the same resonances to move upfield. Virtually no change in the chemical shift was seen between pH 2.0 and 12.0. These results are consistent with the idea that a sufficient concentration of H3O+ led to polymer swelling compared to Na+, while substituting Cl– with OH– reduced swelling. Finally, classical all-atom molecular dynamics (MD) simulations were performed with a monomer and 5-mer corresponding to PNIPAM. The results correlated closely with the thermodynamic and spectroscopic data. The simulation showed that H3O+ ions more readily accumulated around the amide oxygen moiety on PNIPAM compared with Na+. On the other hand, OH– was more excluded from the polymer surface than Cl–. Taken together, the thermodynamic, spectroscopic, and MD simulation data revealed that H3O+ was less depleted from hydrophobic polymer/water interfaces than any of the monovalent Hofmeister metal cations or even Ca2+ and Mg2+. As such, it should be placed on the far-right side of the cationic Hofmeister series. On the other hand, OH– was excluded from the interface and could be positioned in the anionic Hofmeister series between H2PO4– and SO42–. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0013-9351 222 2023 Environmental water in Kolkata is suitable for the survival of Vibrio cholerae O1 115374 EN Eizo Takahashi Collaborative Research Center of Okayama University for Infectious Diseases in India Kei Kitahara Collaborative Research Center of Okayama University for Infectious Diseases in India Shin-ichi Miyoshi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences of Okayama University Goutam Chowdhury National Institute of Cholera and Enteric Diseases Asish K. Mukhopadhyay National Institute of Cholera and Enteric Diseases Shanta Dutta National Institute of Cholera and Enteric Diseases Sadayuki Ochi Department of Health Pharmacy, Yokohama University of Pharmacy Keinosuke Okamoto Graduate School of Medicine, Dentistry and Pharmaceutical Sciences of Okayama University Many patients with cholera emerge in Kolkata, India throughout the year. Such emergency indicates that cholera toxin-producing Vibrio cholerae O1 (toxigenic V. cholerae O1) are widespread in Kolkata. This suggests that the suitable conditions for replication of toxigenic V. cholerae O1 is provided in Kolkata. In previous studies, we found that the replication rate of toxigenic V. cholerae O1 is low in the low ionic aqueous solution. Then we measured the ion concentration in the environmental water of Kolkata. As a control, we measured them in Japanese environmental water. The ion concentration in the environmental water of Kolkata was significantly high. Then, we examined the survival of toxigenic V. cholerae O1 in groundwater from Kolkata and found that V. cholerae O1 survive for long time in the solution but not in the solution diluted with Milli Q water. In addition, we found that V. cholerae O1 proliferated in environmental water of Kolkata to which a small amount of nutrient was added, but did not grow in the environmental water diluted with water to which the same amount of nutrient was added. These results indicate that the environmental water from Kolkata is suitable for survival of V. cholerae O1. No potential conflict of interest relevant to this article was reported.

Japanese Society for Medical and Biological Engineering Acta Medica Okayama 2187-5219 12 2023 Transepidermal Water Loss Estimation Model for Evaluating Skin Barrier Function 1 8 EN Osamu Uehara Medical Engineering Laboratory, ALCARE Co., Ltd. Toshimasa Kusuhara Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Takao Nakamura Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Deterioration of skin barrier function causes symptoms such as allergies because it allows various chemical substances to enter the human body. Quantitative evaluation of the thickness and water content of the stratum corneum is useful as a measure of skin barrier function in fields such as dermatology, nursing science, and cosmetics development. The stratum corneum is responsible for most of the skin barrier function, and this function has conventionally been evaluated using transepidermal water loss (TEWL). In this paper, we propose a new model for estimation of TEWL from measurements of the thickness of the stratum corneum and water content of the surface of the stratum corneum, and discuss the results of the measurements. By measuring the thickness and water content of the stratum corneum using confocal laser microscopy and confocal Raman spectroscopy, respectively, and examining the relationship of these variables with TEWL, we established a new potential model for estimating TEWL from these two variables. The correlation coefficient of the validation data was 0.886 and the root mean squared error was 8.18 points. These findings indicate the feasibility of qualitative evaluation of TEWL by measuring the thickness and water content of the stratum corneum. No potential conflict of interest relevant to this article was reported.

Informa UK Limited Acta Medica Okayama 0038-0768 71 2 2024 Effects of aged microplastics on paddy soil properties and greenhouse gas emissions under laboratory aerobic conditions 215 224 EN Tian Zhang Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Satoshi Akao Faculty of Science and Engineering, Doshisha University Nozomi Nakahara Environmental Management Center, Okayama University Gamamada Liyanage Erandi Priyangika Perera Graduate School of Environmental and Life Science, Okayama University Chiyu Nakano Graduate School of Natural Science and Technology, Okayama University Morihiro Maeda Graduate School of Environmental and Life Science, Okayama University Microplastics (MPs) formed after changes in chemical or physical properties may alter soil properties, which in turn may affect microbial activities and greenhouse gas (GHG) emissions. However, few studies have focused on the effects of aged MPs changes on soil properties and greenhouse gas emissions. Therefore, we aimed to investigate the impact of MPs with different aging times on soil GHG emissions and dissolved organic carbon (DOC). Low-density polyethylene (PE) and polylactic acid (PLA) were treated with ultraviolet (UV) irradiation for 0–2 weeks. Soil was incubated with PE or PLA 1% (w/w) concentration at 60% water holding capacity (WHC) for 35 days. Emissions of nitrous oxide (N2O) and carbon dioxide (CO2) were measured on days 0, 1, 3, 5, 7, 14, 21, 28, and 35. Results showed that CO2 and N2O emissions were higher (p < 0.05) in MPs-amended treatments than those without MPs and increased with MPs age. The addition of virgin PE did not affect soil DOC content, whereas aged PE and all PLA additions significantly increased soil DOC content on day 0, probably because UV irradiation caused the degradation of MPs to smaller molecules. In addition, aged MPs addition altered DOC spectral characteristics on day 7, possibly because aged PE and PLA promote microbial decomposition of organic matter by altering soil properties. Changes in soil DOC content and specific ultraviolet absorbance (SUVA) by aged PE and PLA probably promoted the emissions of CO2 and N2O compared to virgin MPs or soil only. Our study revealed that aged PE and PLA promote GHG emissions from soil by changing DOC contents and qualities. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 161 21 2024 The nature of the hydrophobic interaction varies as the solute size increases from methane’s to C60’s 214501 EN Hidefumi Naito Department of Chemistry, Faculty of Science, Okayama University Tomonari Sumi Department of Chemistry, Faculty of Science, Okayama University Kenichiro Koga Department of Chemistry, Faculty of Science, Okayama University The hydrophobic interaction, often combined with the hydrophilic or ionic interactions, makes the behavior of aqueous solutions very rich and plays an important role in biological systems. Theoretical and computer simulation studies have shown that the water-mediated force depends strongly on the size and other chemical properties of the solute, but how it changes with these factors remains unclear. We report here a computer simulation study that illustrates how the hydrophobic pair interaction and the entropic and enthalpic terms change with the solute size when the solute–solvent weak attractive interaction is unchanged with the solute size. The nature of the hydrophobic interaction changes qualitatively as the solute size increases from that of methane to that of fullerene. The potential of mean force between small solutes has several well-defined extrema, including the third minimum, whereas the potential of mean force between large solutes has the deep contact minimum and the large free-energy barrier between the contact and the water-bilayer separated configurations. The difference in the potential of mean force is related to the differences in the water density, energy, and hydrogen bond number distributions in the vicinity of the pairs of hydrophobic solutes. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-3417 14 23 2024 Preparation of Nano- and Microparticles Obtained from Polymerization Reaction and Their Application to Surface Coating of Woody Materials 11326 EN Toshinori Shimanouchi Department of Environmental Chemistry and Materials, Okayama University, Daichi Hirota Department of Environmental Chemistry and Materials, Okayama University, Masafumi Yoshida Department of Environmental Chemistry and Materials, Okayama University, Kazuma Yasuhara Division of Materials Science, Nara Institute of Science and Technology (NAIST) Yukitaka Kimura Department of Environmental Chemistry and Materials, Okayama University, A surface coating of polymer particles of different hydrophobicity and wide-ranged size is helpful for the surface modification of materials such as woody thin board (WTB) derived from biomass. A preparation method for polymer particles was, in this study, proposed using a capillary-type flow system. Under hydrothermal conditions, the refinement of dispersed oil droplets in water (O/W emulsions) and the polymerization reaction could be simultaneously advanced, and polymer particles of polystyrene (PS), polyvinyl alcohol (PVA), polymethyl methacrylate (PMMA), and poly-L-lactic acid (PLLA) with a particle size of about 100 nm could be synthesized. The coating of polymer particles gave an improved effect on the water repellency of WTBs due to the hydrophobicity of polymer particles and an alteration of surface roughness, and it also provided long-term stability (more than 6 years). No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 9 50 2024 Conformational Flexibility of D1-Glu189: A Crucial Determinant in Substrate Water Selection, Positioning, and Stabilization within the Oxygen-Evolving Complex of Photosystem II 50041 50048 EN Hiroshi Isobe Research Institute for Interdisciplinary Science, Okayama University Takayoshi Suzuki Research Institute for Interdisciplinary Science, Okayama University Michihiro Suga Research Institute for Interdisciplinary Science, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Okayama University Kizashi Yamaguchi Center for Quantum Information and Quantum Biology, Osaka University Photosynthetic water oxidation is a vital process responsible for producing dioxygen and supplying the energy necessary to sustain life on Earth. This fundamental reaction is catalyzed by the oxygen-evolving complex (OEC) of photosystem II, which houses the Mn4CaO5 cluster as its catalytic core. In this study, we specifically focus on the D1-Glu189 amino acid residue, which serves as a direct ligand to the Mn4CaO5 cluster. Our primary goal is to explore, using density functional theory (DFT), how the conformational flexibility of the D1-Glu189 side chain influences crucial catalytic processes, particularly the selection, positioning, and stabilization of a substrate water molecule within the OEC. Our investigation is based on a hypothesis put forth by Li et al. (Nature, 2024, 626, 670), which suggests that during the transition from the S2 to S3 state, a specific water molecule temporarily coordinating with the Ca ion, referred to as O6*, may exist as a hydroxide ion (OH-). Our results demonstrate a key mechanism by which the detachment of the D1-Glu189 carboxylate group from its coordination with the Ca ion allows the creation of a specialized microenvironment within the OEC that enables the selective attraction of O6* in its deprotonated form (OH-) and stabilizes it at the catalytic metal (MnD) site. Our findings indicate that D1-Glu189 is not only a structural ligand for the Ca ion but may also play an active and dynamic role in the catalytic process, positioning O6* optimally for its subsequent participation in the oxidation sequence during the water-splitting cycle. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0378-3774 306 2024 Regional-scale evaluation of tertiary irrigation system in Muda Irrigation Scheme from space 109175 EN Aliya Mhd Zahir Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University A tertiary irrigation system is essential for efficient water management in large-scale irrigation scheme and requires regular evaluation to understand their effectiveness. The current water balance method for tertiary irrigation system evaluation requires extensive data, making continuous monitoring over vast areas unfeasible. A better approach using geospatial data from the Google Earth Engine (GEE) is introduces to evaluate the efficiency of tertiary irrigation systems on a regional scale, aiding water management strategies. This study aims to (1) define the rice cultivation boundary for accurate data collection and (2) quantitatively evaluate irrigation system performance using specific indicators. Remote sensing evapotranspiration (RS-ET) and yield derived from Normalized Difference Vegetation Index (NDVI) were collected within rice cultivation boundary across 60 irrigation blocks, including 14 blocks equipped with tertiary irrigation system in Region II of the Muda Irrigation Scheme. Three irrigation system performance indicators (equity, adequacy, and water productivity) were used as a key metric in over four rice-growing seasons to evaluate tertiary irrigation system. Results reveal that tertiary irrigation system performance varies with the current three-phase water management strategy. Equity performance was highest during the off-season, particularly in phase 1 (2–8 %). Adequacy was moderate across all phases and seasons (median: 0.6–0.67), while water productivity showed consistent strength in phases 1 and 3, with fluctuations in phase 2, across seasons. This study underscores the cost-effectiveness and efficiency of using geospatial data from space for continuous regional-scale monitoring, highlighting areas for improvement in the current water management strategy. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2024 Water use properties contributing to the maintenance of plant biomass and grain production in NERICA upland rice subjected to dry soils EN NGUYEN THI THANH HIEN Graduate School of Environmental and Life Science, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2024 Sustainable Practice for Water-Scarce Agriculture: Enhancing Soil Water Retention and Plant Growth Efficiency with Cellulose Nanofibers EN NGO THUY AN Graduate School of Environmental and Life Science, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2024 クロスカルメロースナトリウムの塩基性環境下における高吸水性ゲル化を利用した新規徐放化システムの開発 EN Masato GOMI Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University No potential conflict of interest relevant to this article was reported.

FapUNIFESP (SciELO) Acta Medica Okayama 1984-3143 20 3 2023 Rapid thawing of frozen bull spermatozoa by transient exposure to 70 °C improves the viability, motility and mitochondrial health e20220127 EN Hai Thanh Nguyen Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University Son Quang Do Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University Rukmali Athurupana Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University Takuya Wakai Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University Hiroaki Funahashi Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University Up to now, the definitive conclusion of the positive effects of rapid transient thawing at higher temperatures for shorter durations has not been obtained yet and is still under discussion due to some contradictory findings and limited assessment of post-thawed parameters. The purpose of the current study was to evaluate the effectiveness of rapid thawing in water at 70 °C by using various post-thawed parameters of frozen bull spermatozoa. Experiment 1, monitoring the change of temperature inside frozen bull straw thawed in water at different temperatures. Experiment 2, evaluation of various post-thawed characteristics of frozen bull spermatozoa thawed in water at different temperatures by using a computer-assisted sperm analysis, flow cytometry and immunocytochemistry. The time it took for the temperature inside the straw to warm up to 15 °C was nearly twice as faster when the straw was thawed in 70 °C water compared with 39 °C. Although there were differences among bulls, viability, motility, and mitochondrial membrane potential of spermatozoa thawed at 70 °C for 8 seconds and stabilized at 39 °C for 52 seconds were significantly higher than those of controls (thawed at 39 °C for 60 seconds) at 0 and 3 h after thawing. Just after thawing, however, there were no differences in acrosome integrity and distribution of phospholipase C zeta1, whereas mitochondrial reactive oxygen species production was significantly lower in spermatozoa thawed at 70 °C. From these results, we conclude that rapid thawing at 70 °C and then stabilization at 39 °C significantly improves viability, motility and mitochondrial health of bull spermatozoa rather than conventional thawing at 39 °C. The beneficial effect of rapid transient thawing could be due to shorter exposure to temperatures outside the physiological range, consequently maintaining mitochondrial health. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0947-6539 30 70 2024 MoSe2-Sensitized Water Splitting Assisted by C60-Dendrons on the Basal Surface e202402690 EN Tomoyuki Tajima Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tomoki Matsuura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Arif Efendi Department of Materials Design and Engineering, University of Toyama Mariko Yukimoto Department of Materials Design and Engineering, University of Toyama Yutaka Takaguchi Department of Materials Design and Engineering, University of Toyama To facilitate water splitting using MoSe2 as a light absorber, we fabricated water-dispersible MoSe2/C60-dendron nanohybrids via physical modification of the basal plane of MoSe2. Upon photoirradiation, the mixed-dimension MoSe2/C60 (2D/0D) heterojunction generates a charge-separated state (MoSe2⋅+/C60⋅−) through electron extraction from the exciton in MoSe2 to C60. This process is followed by the hydrogen evolution reaction (HER) from water in the presence of a sacrificial donor (1-benzyl-1,4-dihydronicotinamide) and co-catalyst (Pt-PVP). The apparent quantum yields of the HER were estimated to be 0.06 % and 0.27 % upon photoexcitation at the A- and B-exciton absorption peaks (λmax=800 and 700 nm), respectively. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2024 11 2024 Measurement of γ-Rays Generated by Neutron Interaction with 16O at 30 MeV and 250 MeV 113D01 EN T. Tano Department of Physics, Okayama University T. Horai Department of Physics, Okayama University Y. Ashida Department of Physics and Astronomy, University of Utah Y. Hino Department of Physics, Okayama University F. Iacob Department of Physics and Astronomy, University of Padova A. Maurel Ecole Polytechnique, IN2P3-CNRS, Laboratoire Leprince-Ringuet M. Mori National Astronomical Observatory of Japan G. Collazuol Department of Physics and Astronomy, University of Padova A. Konaka TRIUMF Y. Koshio Department of Physics, Okayama University T. Nakaya Department of Physics, Kyoto University T. Shima Research Center for Nuclear Physics (RCNP) R. Wendell Department of Physics, Kyoto University Deep understanding of γ-ray production from the fast neutron reaction in water is crucial for various physics studies at large-scale water Cherenkov detectors. We performed test experiments using quasi-mono energetic neutron beams (⁠En = 30 and 250 MeV) at Osaka University’s Research Center for Nuclear Physics to measure γ-rays originating from the neutron–oxygen reaction with a high-purity germanium detector. Multiple γ-ray peaks which are expected to be from excited nuclei after the neutron–oxygen reaction were successfully observed. We measured the neutron beam flux using an organic liquid scintillator for the cross section measurement. With a spectral fitting analysis based on the tailored γ-ray signal and background templates, we measured cross sections for each observed γ-ray component. The results will be useful to validate neutron models employed in ongoing and future water Cherenkov experiments. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0340-5761 99 2 2024 Therapeutic potential of 4-phenylbutyric acid against methylmercury-induced neuronal cell death in mice 563 574 EN Ryohei Miki Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ryosuke Nomura Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuta Iijima Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sho Kubota Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takao Iwawaki Division of Cell Medicine, Department of Life Science, Medical Research Institute, Kanazawa Medical University Masatake Fujimura Department of International Affairs and Research, National Institute for Minamata Disease Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Methylmercury (MeHg) is an environmental neurotoxin that induces damage to the central nervous system and is the causative agent in Minamata disease. The mechanisms underlying MeHg neurotoxicity remain largely unknown, and there is a need for effective therapeutic agents, such as those that target MeHg-induced endoplasmic reticulum (ER) stress and the unfolded protein response (UPR), which is activated as a defense mechanism. We investigated whether intraperitoneal administration of the chemical chaperone, 4-phenylbutyric acid (4-PBA), at 120 mg/kg/day can alleviate neurotoxicity in the brains of mice administered 50 ppm MeHg in drinking water for 5 weeks. 4-PBA significantly reduced MeHg-induced ER stress, neuronal apoptosis, and neurological symptoms. Furthermore, 4-PBA was effective even when administered 2 weeks after the initiation of exposure to 30 ppm MeHg in drinking water. Our results strongly indicate that ER stress and the UPR are key processes involved in MeHg toxicity, and that 4-PBA is a novel therapeutic candidate for MeHg-induced neurotoxicity. No potential conflict of interest relevant to this article was reported.

Japan Society of Hydrology and Water Resources Acta Medica Okayama 1882-3416 15 3 2021 Evaluation of drought features in the Dakbla watershed, Central Highlands of Vietnam 77 83 EN Vo Ngoc Quynh Tram Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University The drought impacts in the Dakbla watershed were assessed based on a combination of hydrological modeling and drought indices. Three drought indices, the Standardized Precipitation Index (SPI), Standardized Soil Moisture Index (SSI), and Streamflow Drought Index (SDI) were utilized to evaluate the drought features of meteo-hydrology and agriculture. The results indicated that these indices are well adapted to the local conditions, especially the 12-month time scale. Evaluations of drought features on the watershed scale could provide more specific information regarding drought risk than regional-scale/district-level assessments, because a watershed is a hydrologically fundamental unit to consider water resources management. Additionally, evaluations of drought impacts using the SSI showed longer and higher trends than those using the SPI and SDI in terms of drought duration and frequency. Considering the spatial distribution of drought frequency, the areas predominated by agricultural land in the target watershed had higher drought risk. Thus, assessment of agricultural droughts along with meteo-hydrological droughts is extremely important to support realistic local drought management strategies by considering water availability, water balance, and soil characteristics, especially in specific agricultural areas. No potential conflict of interest relevant to this article was reported.

Japan Society of Hydrology and Water Resources Acta Medica Okayama 1882-3416 18 4 2024 Evaluation and selection of a set of CMIP6 GCMs for water resource modeling in the poorly gauged complex terrain of the Tana River basin in Kenya 87 94 EN Daniel Mwendwa Wambua Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University The Tana River basin is among the least monitored in terms of meteorological data in Kenya. The Kenya Meteorological Department (KMD) provided data on a ten-day timescale, which is not adequate for water resource evaluation. To bridge this data gap, there is a growing need to leverage General Circulation Models (GCMs) and global datasets to assess current and future water resources in this basin. This study focused on evaluating the performance of 19 CMIP6 GCMs concerning precipitation (pr), maximum temperature (tasmax), and minimum temperature (tasmin) for the complex terrain of the Tana River basin. This involved a rigorous process of disaggregating the data provided by the KMD into a daily timescale for downscaling. The GCMs’ historical output was prepared using the Climate Data Operator (CDO) in Cygwin. The Kling Gupta Efficiency (KGE) was computed for each variable at three stations: Nyeri (upstream), Kitui (midstream), and Bura (downstream). The KGE results were validated using Taylor statistics. Five GCMs, CMCC-ESM2, MPI-ESM1-2-HR, ACCESS-CM2, NorESM2-MM, and GFDL-ESM4, performed best with a multivariable Multi-station KGE statistic of 0.455–0.511. The outputs from these selected GCMs were subsequently downscaled for later use in assessing the water resources and crop water demand in the basin. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2024 10 2024 Study of the Neutrino–Oxygen Cross Sections of the Charged-Current Reaction 16O(ν̄e, e+)16N(0 MeV, 2–) and the Neutral-Current Reaction 16O(ν, ν′)16O(12.97/12.53 MeV, 2–), Producing High-Energy γ Rays 103D01 EN Makoto Sakuda Physics Department, Okayama University Toshio Suzuki Department of Physics, College of Humanities and Sciences, Nihon University Ken'Ichiro Nakazato Faculty of Arts and Science, Kyushu University Hideyuki Suzuki Department of Physics, Faculty of Science and Technology, Tokyo University of Science In our previous work, we discussed the cross section and the detection of 4.4 MeV γ rays produced in the neutrino neutral-current (NC)reaction 16O(ν, ν′)16O(12.97 and 12.53 MeV, 2−) in a water Cherenkov detector at low energy below 100 MeV. In this report, we further investigate both the charged-current reaction 16O(ν¯e, e+)16N(0 MeV, 2−) and the NC reaction16O(ν, ν′)16O(12.97 and 12.53 MeV, 2−), producing high-energy γ rays, in which a more solid identification of the reactions can be applied via the coincidence method. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1618-2642 416 28 2024 Comparison of protein immobilization methods with covalent bonding on paper for paper-based enzyme-linked immunosorbent assay 6679 6686 EN Yang Chen Department of Chemistry, Okayama University Kaewta Danchana Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University In this study, two methods were examined to optimize the immobilization of antibodies on paper when conducting a paper-based enzyme-linked immunosorbent assay (P-ELISA). Human IgG, as a test-capture protein, was immobilized on paper via the formation of Schiff bases. Aldehyde groups were introduced onto the surface of the paper via two methods: NaIO4 and 3-aminopropyltriethoxysilane (APTS) with glutaraldehyde (APTS-glutaraldehyde). In the assay, horseradish peroxidase-conjugated anti-human IgG (HRP-anti-IgG) binds to the immobilized human IgG, and the colorimetric reaction of 3,3′,5,5′-tetramethylbenzyzine (TMB) produces a blue color in the presence of H2O2 and HRP-anti-IgG as a model analyte. The immobilization of human IgG, the enzymatic reaction conditions, and the reduction of the chemical bond between the paper surface and immobilized human IgG all were optimized in order to improve both the analytical performance and the stability. In addition, the thickness of the paper was examined to stabilize the analytical signal. Consequently, the APTS-glutaraldehyde method was superior to the NaIO4 method in terms of sensitivity and reproducibility. Conversely, the reduction of imine to amine with NaBH4 proved to exert only minimal influence on sensitivity and stability, although it tended to degrade reproducibility. We also found that thick paper was preferential when using P-ELISA because a rigid paper substrate prevents distortion of the paper surface that is often caused by repeated washing processes. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1022-1336 46 1 2024 Elastomer Particle Monolayers Formed by the Compression of Poly(methyl acrylate) Microparticles at an Air/Water Interface 2400604 EN Yuma Sasaki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuichiro Nishizawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Natsuki Watanabe Department of Physics, Nagoya University Takayuki Uchihashi Department of Physics, Nagoya University Daisuke Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University In the previous study (Green Chem., 2023, 25, 3418), highly stretchable and mechanically tough poly(methyl acrylate) (pMA) microparticle-based elastomers can be formed by drying a microparticle-containing aqueous dispersion. This discovery has the potential to overcome the mechanical weakness of industrially produced aqueous latex films. However, in 3D-arranged particle films, structural complexity, such as the existence of defects, makes it difficult to clearly understand the relationship between the particle film structure and its mechanical properties. In this study, 2D-ordered pMA particle monolayers at the air/water interface of a Langmuir trough are prepared. Under high compression at the air/water interface, the microparticles contact their neighboring particles, and the resulting monolayers can be successfully transferred onto a solid substrate. The compression of the monolayer films is linked to an increase in the elastic modulus of the monolayer film on the solid substrate as evident from the local Young's modulus mapping using atomic force microscopy. Thus, pMA particle films with different mechanical properties can be created using a Langmuir trough. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0928-0707 112 2 2024 Electrochemically assisted sol-gel deposition of bioactive gels for biomedical applications 419 424 EN Tomohiko Yoshioka Biomaterials Laboratory, Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Naoki Miyamoto Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Satoshi Hayakawa Biomaterials Laboratory, Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University So far, the sol-gel process has been available to prepare precursor gels of bioactive glasses with various compositions. In this report, we described a novel coating method of bioactive gels on a titanium substrate where the sol-gel transition is controlled by applying external electric fields. The application of a constant current of 10 mA/cm2 in an acidic sol containing pre-hydrolyzed tetraethoxysilane, calcium nitrate, and ammonium dihydrogen phosphate led to the deposition of gels on the titanium cathodes due to the generation of OH– by water electrolysis as a catalyst of the sol-gel transition. The obtained gels, which were characterized to be amorphous and consisted of Si, Ca, and P, covered the titanium substrates as a coating. The bioactivity of the gels deposited was confirmed by soaking in a simulated body fluid (SBF) up to 7 days, suggesting that the electrochemically assisted sol-gel process is promising for providing bioactive coatings on metallic implants. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2073-4360 16 16 2024 Long-Term Bonding Performance of One-Bottle vs. Two-Bottle Bonding Agents to Lithium Disilicate Ceramics 2266 EN Masao Irie Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiro Okada Department of Dental Biomaterials, Tohoku University Graduate School of Dentistry Yukinori Maruo Department of Prosthodontics, Okayama University Hospital Goro Nishigawa Department of Prosthodontics, Okayama University Hospital Takuya Matsumoto Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences The aim of this study was to compare the long-term bonding performance to lithium disilicate (LDS) ceramic between one-bottle and two-bottle bonding agents. Bonding performance was investigated under these LDS pretreatment conditions: with hydrofluoric acid (HF) only, without HF, with a two-bottle bonding agent (Tokuyama Universal Bond II) only. Shear bond strengths between LDS and nine resin cements (both self-adhesive and conventional adhesive types) were measured at three time periods: after one-day water storage (Base), and after 5000 and 20,000 thermocycles (TC 5k and TC 20k respectively). Difference in degradation between one- and two-bottle bonding agents containing the silane coupling agent was compared by high-performance liquid chromatography. With HF pretreatment, bond strengths were not significantly different among the three time periods for each resin cement. Without HF, ESTECEM II and Super-Bond Universal showed significantly higher values than others at TC 5k and TC 20k when treated with the recommended bonding agents, especially at TC 20k. Difference in degradation between one- and two-bottle bonding agents containing the silane coupling agent was compared by high-performance liquid chromatography (HPLC). For both cements, these values at TC 20k were also not significantly different from pretreatment with only Tokuyama Universal Bond II. For LDS, long-term bond durability could be maintained by pretreatment with Tokuyama Universal Bond II instead of the hazardous HF. No potential conflict of interest relevant to this article was reported.

Frontiers Media Acta Medica Okayama 1664-462X 15 2024 Lentil adaptation to drought stress: response, tolerance, and breeding approaches 1403922 EN Md. Mahmud Al Noor Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture Md. Tahjib-Ul-Arif Graduate School of Environmental, Life, Natural Science and Technology, Okayama University S. M. Abdul Alim Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture Md. Mohimenul Islam Horticulture Division, Bangladesh Institute of Nuclear Agriculture Md. Toufiq Hasan Department of Biotechnology, Bangladesh Agricultural University Md. Ali Babar Agronomy Departments, University of Florida Mohammad Anwar Hossain Department of Genetics and Plant Breeding, Bangladesh Agricultural University Zilhas Ahmed Jewel Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Science and Technology University Yoshiyuki Murata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mohammad Golam Mostofa Department of Biochemistry and Molecular Biology, Michigan State University Lentil (Lens culinaris Medik.) is a cool season legume crop that plays vital roles in food and nutritional security, mostly in the least developed countries. Lentil is often cultivated in dry and semi-dry regions, where the primary abiotic factor is drought, which negatively impacts lentil growth and development, resulting in a reduction of yield. To withstand drought-induced multiple negative effects, lentil plants evolved a variety of adaptation strategies that can be classified within three broad categories of drought tolerance mechanisms (i.e., escape, avoidance, and tolerance). Lentil adapts to drought by the modulation of various traits in the root system, leaf architecture, canopy structure, branching, anatomical features, and flowering process. Furthermore, the activation of certain defensive biochemical pathways as well as the regulation of gene functions contributes to lentil drought tolerance. Plant breeders typically employ conventional and mutational breeding approaches to develop lentil varieties that can withstand drought effects; however, little progress has been made in developing drought-tolerant lentil varieties using genomics-assisted technologies. This review highlights the current understanding of morpho-physiological, biochemical, and molecular mechanisms of lentil adaptation to drought stress. We also discuss the potential application of omics-assisted breeding approaches to develop lentil varieties with superior drought tolerance traits. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 2666-8319 10 2024 Reduction with zinc - Impact on the determination of nitrite and nitrate ions using microfluidic paper-based analytical devices 100347 EN Mika I. Umeda Okayama University Kaewta Danchana Okayama University Takatoshi Fujii National Institute of Technology, Yonago College Eiichi Hino National Institute of Technology, Yonago College Yusuke Date National Institute of Technology, Yonago College Kaoru Aoki National Institute of Technology, Yonago College Takashi Kaneta Okayama University We used a microfluidic paper-based analytical device (mu PAD) to investigate the influence that zinc reduction exerts on the determination of nitrite and nitrate ions in natural water samples. The mu PAD consists of layered channels for the reduction of nitrate to nitrite with zinc powder and the subsequent detection of nitrite with Griess reagent. The amount of zinc, number of layers, and reaction time for the reduction were optimized to obtain an intense signal for nitrate. Initially, the sensitivity to nitrate corresponded to 55% that of nitrite, which implied an incomplete reduction. We found, however, that zinc decreased the sensitivity to nitrite in both the mu PAD and spectrophotometry. The sensitivity to nitrite was decreased by 48% in spectrophotometry and 68% in the mu PAD following the reaction with zinc. One of the reasons for the decreased sensitivity is attributed to the production of ammonia, as we elucidated that both nitrite and nitrate produced ammonia via the reaction with zinc. The results suggest that the total concentration of nitrite and nitrate must be corrected by constructing a calibration curve for nitrite with zinc, in addition to developing curves for nitrate with zinc and for nitrite without zinc. Using these calibration curves, the absorbance at different concentration ratios of nitrite and nitrate ions could be reproduced via calculation using the calibration curves with zinc for nitrite and nitrate. Eventually, the developed mu PAD was applied to the determination of nitrite and nitrate ions in natural water samples, and the results were compared with those using a conventional spectrophotometric method. The results of the mu PAD are in good agreement with those of conventional spectrophotometry, which suggests that the mu PAD is reliable for the measurement of nitrite and nitrate ions in natural water samples. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1387-1811 378 2024 Mesoporous carbon with extremely low micropore content synthesized from graphene oxide modified with alkali metal nitrates 113269 EN Zhao Li Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Moeto Toyota Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Takahiro Ohkubo Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University High-temperature thermal exfoliation is a simple, rapid, and cost-efficient method for transforming graphene oxide (GO) materials into reduced graphene oxide (rGO) materials. In this study, GO materials were dispersed with alkali metal nitrates (MNO3), leading to the preparation of porous rGO materials characterized by high specific surface area (SSA) and pore volume via high-temperature thermal exfoliation. Experimental data indicate that the metal cations of MNO3 tend to react directly with the oxygen functional groups (OFG) of GO, modulating the OFG content. Simultaneously, nitrate anions have preferential interaction with alkali metal ions and adhere to the surface of the GO. The presence of MNO3 on the surface of GO facilitates the thermal exfoliation process and leads to the formation of structures with an extremely high proportion of mesoporous content. The isothermal gas adsorption results show that the exfoliation efficiency of the samples activated with different nitrate salts decreases in the order rGO-KNO3 > rGO-NaNO3 > rGO-LiNO3. Among these samples, rGO modified with KNO3 exhibited the greatest exfoliation efficiency, with a mesopore-to-micropore volume ratio of 22.4, more than 1.7 times that of rGO. Its SSA and pore volume were 359 m2 g−1 and 1.26 cm3 g−1, respectively. These values significantly surpass those of rGO. Our research findings demonstrate that activation with MNO3 significantly increases the SSA and pore volume of the GO material after high-temperature annealing. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 40 32 2024 Effect of Droplet-Removal Processes on Fog-Harvesting Performance on Wettability-Controlled Wire Array with Staggered Arrangement 16994 17000 EN Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Junya Oka Graduate School of Natural Science and Technology, Okayama University Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Development of freshwater resources is vital to overcoming severe worldwide water scarcity. Fog harvesting has attracted attention as a candidate technology that can be used to obtain fresh water from a stream of foggy air without energy input. Drainage of captured droplets from fog harvesters is necessary to maintain the permeability of harp-shaped harvesters. In the present study, we investigated the effect of the droplet-removal process on the amount of water harvested using a harvester constructed by wettability-controlled wires with an alternating and staggered arrangement. Droplet transfer from hydrophobic to hydrophilic wires, located upstream and downstream of the fog flow, respectively, was observed with a fog velocity greater than 1.5 m/s. The proportion of harvesting resulting from droplet transfer exceeded 30% of the total, and it reflected more than 20% increase of the harvesting performance compared with that of a harvester with wires of the same wettability: this value varied with the adhesive property of the wires and fog velocity. Scaled-up and multilayered harvesters were developed to enhance harvesting performance. We demonstrated certain enhancements under multilayered conditions and obtained 15.99 g/30 min as the maximum harvested amount, which corresponds to 13.3% of the liquid contained in the fog stream and is enhanced by 10% compared with that without droplet transfer. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1744-683X 20 29 2024 Relationship between π–A isotherms and single microgel/microgel array structures revealed via the direct visualization of microgels at the air/water interface 5836 5847 EN Takahisa Kawamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruka Minato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Daisuke Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The structures of single microgels and microgel arrays formed at the air/water interface were visualized directly, and their structures correlated with π–A isotherms in order to understand the compression behavior of soft and deformable microgels at this interface. Large microgels (ca. 4 μm) were synthesized so that these can be clearly visualized at the air/water interface, even under high compression, and a series of microgel compression experiments were directly evaluated using a Langmuir trough equipped with a fluorescence microscope. The experiments revealed that upon compressing the microgel arrays at the interface voids disappeared and colloidal crystallinity increased. However, the colloidal crystallinity decreased when the microgel arrays were strongly compressed. In addition, when the structures were observed at higher magnification, it became clear that the single microgel structures, when visualized from above, changed from circular to polygonal upon compressing the microgel array. The results of this study can be expected to improve the understanding of the compression behavior of microgel arrays adsorbed at the air/water interface and will thus be useful for the creation of new functional microgel stabilizers with potential applications in e.g., bubbles and emulsions. No potential conflict of interest relevant to this article was reported.

Japan Concrete Institute Acta Medica Okayama 1346-8014 22 5 2024 Freeze-thaw Resistance of Concrete using Ground Granulated Blast-furnace Slag and Blast-furnace Slag Sand in Salt Water 253 266 EN Toshiki Ayano Faculty of Environmental, Life, Natural Science and Technology, Okayama University Takashi Fujii Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kanako Okazaki Division of Social Engineering and Environmental Management, Graduate School of Environmental and Life Science, Okayama University The freeze-thaw resistance of concrete is significantly lower in salt water than in fresh water. Concrete deteriorates through repeated freezing and thawing, but in salt water, freezing alone leads to destruction. This paper investigated the effect of calcium hydroxide in concrete on the failure of concrete under such low temperatures. Calcium hydroxide precipitates at the transition zone between aggregate and cement paste due to the hydration of cement. The lower the temperature and the higher the concentration of salt water, the more calcium hydroxide dissolves. From concrete, more calcium hydroxide is eluted in salt water than in fresh water. This accelerates the deterioration of mortar and concrete due to freeze-thaw action. Mortar and concrete using ground granulated blast-furnace slag produces less calcium hydroxide. In mortar and concrete using blast-furnace slag sand, calcium hydroxide precipitated around the aggregate reacts with cement paste and blast-furnace slag sand to modify the transition zone. From these results, it was clarified that concrete using blast-furnace slag exhibits high freeze-thaw resistance even in salt water.<br> This paper is the English translation of the authors’ previous work [Ayano, T., Fujii, T. and Okazaki, K., (2023). “Freeze-thaw resistance of concrete using ground granulated blast-furnace and blast-furnace slag sand in salt water.” Japanese Journal of JSCE, 79(12), 23-00042. (in Japanese)]. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 78 3 2024 Spontaneous Bilateral Pneumothorax in a Patient with Anorexia Nervosa: The Management of Prolonged Postoperative Air Leakage 281 284 EN Kazuhiro Okada Department of Thoracic Surgery, Hiroshima City Hiroshima Citizens Hospital Yuho Maki Department of Thoracic Surgery, Hiroshima City Hiroshima Citizens Hospital Kei Matsubara Department of Thoracic Surgery, Hiroshima City Hiroshima Citizens Hospital Yutaka Hirano Department of Thoracic Surgery, Hiroshima City Hiroshima Citizens Hospital Toshiya Fujiwara Department of Thoracic Surgery, Hiroshima City Hiroshima Citizens Hospital Motoki Matsuura Department of Thoracic Surgery, Hiroshima City Hiroshima Citizens Hospital Case Report 10.18926/AMO/67203 A 24-year-old Japanese female with anorexia nervosa presented to our hospital for bilateral pneumothorax, and 12-Fr thoracostomy catheters were inserted into the bilateral pleural cavities. On hospital day 9, a thoracoscopic bullectomy was performed. However, air leakage relapsed on both sides on postoperative day 1. The air leakage on the right side was particularly persistent, and we switched the drainage to a Heimlich valve. Both lungs expanded gradually and the chest tube was removed on postoperative day 19. Passive pleural drainage might be an option for prolonged air leakage after a bullectomy in patients with anorexia nervosa. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 2352-1864 35 2024 Effects of cellulose nanofibers on soil water retention and aggregate stability 103650 EN An Thuy Ngo Graduate School of Environmental and Life Science, Okayama University Yasushi Mori Graduate School of Environmental and Life Science, Okayama University Long Thanh Bui Graduate School of Environmental and Life Science, Okayama University Innovative solutions that address global challenges such as water scarcity and soil erosion are critical for maintaining sustainable agriculture. Due to their water-absorbing and soil-binding properties, cellulose nanofibers (CNF) can be applied to soil to enhance soil water retention and aggregate stability. In this study, we analyzed the effects of the drying temperature, dosage, irrigation water quality, and soil type on the efficacy of CNFs. Our results revealed that CNF dried at 5 degrees C is more effective at absorbing water than others, and adding 1% CNF enhanced soil water content up to 98%. The CNF samples absorbed water due to their hydrophilic molecular groups and morphological structure, as confirmed by Fourier-transform infrared spectroscopy and scanning electron microscopy. CNF addition increased the soil volumetric water content and prolonged water retention by 22 days in the paddy soil samples, highlighting its potential for drought-prone areas. Furthermore, irrigation water quality, such as pH and cation values, influenced the interactions between CNF and water molecules, suggesting adjustments to the water retention curve. In its hydrated state, CNF promotes colloid flocculation and binds to soil particles, thereby strengthening the bonds crucial for aggregate formation and stability. CNF enhanced macro-aggregate formation by up to 48% and 59% in the masa and paddy soil samples, respectively. Our study emphasizes the potential of CNF for water conservation, soil health, and overall agricultural sustainability. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-2607 12 5 2024 Isolation of Vibrio cholerae and Vibrio vulnificus from Estuarine Waters, and Genotyping of V. vulnificus Isolates Using Loop-Mediated Isothermal Amplification 877 EN Shin-Ichi Miyoshi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Megumi Kurata Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Riho Hirose Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masaya Yoshikawa Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yong Liang Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yosuke Yamagishi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tamaki Mizuno Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Bacteria in the genus Vibrio are ubiquitous in estuarine and coastal waters. Some species (including Vibrio cholerae and Vibrio vulnificus) are known human pathogens causing ailments like cholera, diarrhea, or septicemia. Notably, V. vulnificus can also cause a severe systemic infection (known as vibriosis) in eels raised in aquaculture facilities. Water samples were periodically collected from the estuary of the Asahi River, located in the southern part of Okayama City, Japan. These samples were directly plated onto CHROMagar Vibrio plates, and colonies displaying turquoise-blue coloration were selected. Thereafter, polymerase chain reaction was used to identify V. cholerae and V. vulnificus. A total of 30 V. cholerae strains and 194 V. vulnificus strains were isolated during the warm season when the water temperature (WT) was higher than 20 degrees C. Concurrently, an increase in coliforms was observed during this period. Notably, V. vulnificus has two genotypes, designated as genotype 1 and genotype 2. Genotype 1 is pathogenic to humans, while genotype 2 is pathogenic to both humans and eels. The loop-mediated isothermal amplification method was developed to rapidly determine genotypes at a low cost. Of the 194 strains isolated, 80 (41.2%) were identified as genotype 1 strains. Among the 41 strains isolated when the WTs were higher than 28 degrees C, 25 strains (61.0%) belonged to genotype 1. In contrast, of the 32 strains isolated when the WTs were lower than 24 degrees C, 27 strains (84.4%) belonged to genotype 2. These results suggest that the distribution of the two genotypes was influenced by WT. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2075-163X 14 5 2024 Measurements of Thermodynamic Data of Water in Ca-Bentonite by Relative Humidity Method 477 EN Kosuke Ichikawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruo Sato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Buffer material (compacted bentonite), one of the engineered barrier elements in the geological disposal of a high-level radioactive waste, develops swelling stress due to groundwater penetration from the surrounding rock mass. Montmorillonite is the major clay mineral component of bentonite. Even previous studies provide few mechanical and thermodynamic data on Ca-montmorillonite. In this study, thermodynamic data on Ca-montmorillonite were obtained as a function of water content by measuring relative humidity (RH) and temperature. The activities of water and the relative partial molar Gibbs free energies of water were determined from the experimental results, and the swelling stress of Ca-bentonite was calculated using the thermodynamic model and compared with measured data. The activities of water and the relative partial molar Gibbs free energies obtained in the experiments decreased with decreasing water content in water contents lower than about 25%. This trend was similar to that of Na-montmorillonite. The swelling stress calculated based on the thermodynamic model was approximately 200 MPa at a montmorillonite partial density of 2.0 Mg/m3 and approximately 10 MPa at a montmorillonite partial density of 1.4 Mg/m3. The swelling stresses in the high-density region (around 2.0 Mg/m3) were higher than that of Na-montmorillonite and were similar levels in the low-density region (around 1.5 Mg/m3). Comparison with measured data showed the practicality of the thermodynamic model. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2227-9717 12 4 2024 Pyrene-Modified Cyclic Peptides Detect Cu2+ Ions by Fluorescence in Water 746 EN Yuhi Maekawa Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Sora Sakura Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Yuji Furutani Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Rento Fujihara Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Hisashi Sugime Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University The detection of metal ions is an option for maintaining water quality and diagnosing metal ion-related diseases. In this study, we successfully detected metal ions using fluorescent peptides in water. First, we prepared seven linear (L1-L7) and seven cyclic (C1-C7) peptides containing two pyrenyl (Pyr) units and assessed the response to various metal ions by fluorescence. The results indicated that C1, which contains a hexameric cyclic peptide moiety consisting of Pyr and Gly units, did not show a fluorescent response to metal ions, while the linear L1 corresponding to C1 showed a response to Cu2+, but its selectivity was found to be poor through a competition assay for each metal ion. We then assessed C2-C7 and L2-L7, in which Gly was replaced by His units at various positions in the same manner. The results showed that C2-C7 responded to Cu2+ in a manner dependent on the His position. Additionally, superior selectivity was observed in C7 through a competition assay. These results demonstrate that the structural restriction of peptides and the sequence affect the selective detection of Cu2+ and reveal that peptides with an appropriate structure can accomplish the fluorescent detection of Cu2+ specifically. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2075-163X 14 4 2024 Swelling Stress of Bentonite: Thermodynamics of Interlayer Water in K-Montmorillonite in Consideration of Alteration 430 EN Misato Endo Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruo Sato Institute of Academic and Research, Okayama University The buffer material that makes up the geological disposal system of high-level waste swells by contact with groundwater and seals space with rock mass and fractures in rock mass. The buffer material has a function of mechanical buffer with rock pressure, and swelling stress is important in this case. The alteration of bentonite may occur due to the initial replacement of cations (Na+ ions) in the interlayer with K+ ions upon contact with groundwater, but there are no studies on the swelling stress of K-bentonite. In this study, the author prepared K-montmorillonite samples and obtained thermodynamic data on interlayer water as a function of water content using a relative humidity method. The swelling stress was analyzed based on a thermodynamic model developed in earlier studies and compared with measured data. The activity and the relative partial molar Gibbs free energy of porewater decreased with decreasing water content in the region, below approximately 15%. This behavior significantly differs from that of other ions, such as Na. The swelling stress calculated based on the thermodynamic model and date occurred in the region of high density of 1.9 Mg/m3 with montmorillonite partial density. It was indicated for the first time that K-bentonite scarcely swells under realistic design conditions. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2075-163X 14 4 2024 Changes of Temperature and Moisture Distribution over Time by Thermo-Hydro-Chemical (T-H-C)-Coupled Analysis in Buffer Material Focusing on Montmorillonite Content 394 EN Kohei Ouchi Graduate School of Natural Science and Technology, Okayama University Haruo Sato Graduate School of Natural Science and Technology, Okayama University Bentonite is used as a buffer material in engineered barriers for the geological disposal of high-level radioactive waste. The buffer material will be made of bentonite, a natural clay, mixed with silica sand. The buffer material is affected by decay heat from high-level radioactive waste, infiltration of groundwater, and swelling of the buffer material. The analysis of these factors requires coupled analysis of heat transfer, moisture transfer, and groundwater chemistry. The purpose of this study is to develop a model to evaluate bentonite types and silica sand content in a unified manner for thermo-hydro-chemical (T-H-C)-coupled analysis in buffer materials. We focused on the content of the clay mineral montmorillonite, which is the main component of bentonite, and developed a model to derive the moisture diffusion coefficient of liquid water and water vapor based on Philip and de Vries, and Kozeny-Carman. The evolutions of the temperature and moisture distribution in the buffer material were analyzed, and the validity of each distribution was confirmed by comparison with the measured data obtained from an in situ experiment at 350 m in depth at the Horonobe Underground Research Center, Hokkaido, Japan. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-6640 249 2024 How do water-mediated interactions and osmotic second virial coefficients vary with particle size? 440 452 EN Hidefumi Naito Department of Chemistry, Faculty of Science, Okayama University Tomonari Sumi Department of Chemistry, Faculty of Science, Okayama University Kenichiro Koga Department of Chemistry, Faculty of Science, Okayama University We examine quantitatively the solute-size dependences of the effective interactions between nonpolar solutes in water and in a simple liquid. The potential w(r) of mean force and the osmotic second virial coefficients B are calculated with high accuracy from molecular dynamics simulations. As the solute diameter increases from methane's to C60's with the solute–solute and solute–solvent attractive interaction parameters fixed to those for the methane–methane and methane–water interactions, the first minimum of w(r) lowers from −1.1 to −4.7 in units of the thermal energy kT. Correspondingly, the magnitude of B (<0) increases proportional to σα with some power close to 6 or 7, which reinforces the solute-size dependence of B found earlier for a smaller range of σ [H. Naito, R. Okamoto, T. Sumi and K. Koga, J. Chem. Phys., 2022, 156, 221104]. We also demonstrate that the strength of the attractive interactions between solute and solvent molecules can qualitatively change the characteristics of the effective pair interaction between solute particles, both in water and in a simple liquid. If the solute–solvent attractive force is set to be weaker (stronger) than a threshold, the effective interaction becomes increasingly attractive (repulsive) with increasing solute size. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0302-8933 205 10 2023 Flavobacterium okayamense sp. nov. isolated from surface seawater 346 EN Kei Kitahara Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Basilua Andre Muzembo Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sho Morohoshi TechnoSuruga Laboratory Co., Ltd Tadao Kunihiro TechnoSuruga Laboratory Co., Ltd Nozomi Tazato TechnoSuruga Laboratory Co., Ltd Ayumu Ohno Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazuma Uesaka Graduate School of Bioagricultural Sciences, Nagoya University Makoto Taniguchi Oral Microbiome Center, Taniguchi Dental Clinic Shin-ichi Miyoshi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Strain KK2020170T, a Gram-stain negative, yellow colony-forming bacterium, was isolated from surface seawater sampled in Kojima Bay, Okayama, Japan. Phylogenetic analysis based on the 16S rRNA gene revealed that strain KK2020170T belongs to the genus Flavobacterium, with Flavobacterium haoranii LQY-7T (98.1% similarity) being its closest relative, followed by Flavobacterium sediminis MEBiC07310T (96.9%) and Flavobacterium urocaniciphilum YIT 12746T (96.0%). Whole-genome shotgun sequencing showed that strain KK2020170T, when paralleled with F. haoranii LQY-7 T, had 81.3% average nucleotide identity, and 24.6% in silico DNA–DNA hybridization values, respectively. The DNA G + C content of strain KK2020170T was 31.1 mol%. The most abundant fatty acids (> 10%) of strain KK2020170T were iso-C15: 0, iso-C17: 0 3-OH and iso-C15: 1 G. The dominant respiratory quinone of the strain was menaquinone MK-6. Based on the phylogenetic and phenotypic analysis results, we propose that strain KK2020170T represents a novel species, for which the name Flavobacterium okayamense sp. nov. has been proposed. The type strain is KK2020170T (= ATCC TSD-280 T = NBRC 115344 T). No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 78 2 2024 Impacts of Age and Gender on Brain Edema in a Mouse Water Intoxication Model 115 122 EN Emi Nakamura-Maruyama Department of Physiology2, Kawasaki Medical School Keiichiro Irie Department of Neurological Surgery, Kagawa University Faculty of Medicine Kazuhiko Narita Department of Physiology2, Kawasaki Medical School Naoyuki Himi Department of Physiology2, Kawasaki Medical School Osamu Miyamoto Department of Physiology2, Kawasaki Medical School Takehiro Nakamura Department of Physiology2, Kawasaki Medical School Original Article 10.18926/AMO/66914 Brain edema causes abnormal fluid retention and can be fatal in severe cases. Although it develops in various diseases, most treatments for brain edema are classical. We analyzed the impacts of age and gender on the characteristics of a water intoxication model that induces pure brain edema in mice and examined the model’s usefulness for research regarding new treatments for brain edema. C57BL/6J mice received an intraperitoneal administration of 10% body weight distilled water, and we calculated the brain water content by measuring the brain-tissue weight immediately after dissection and after drying. We analyzed 8-OHdG and caspase-3 values to investigate the brain damage. We also applied this model in aquaporin 4 knockout (AQP4−) mice and compared these mice with wild-type mice. The changes in water content differed by age and gender, and the 8-OHdG and caspase-3 values differed by age. Suppression of brain edema by AQP4− was also confirmed. These results clarified the differences in the onset of brain edema by age and gender, highlighting the importance of considering the age and gender of model animals. Similar studies using genetically modified mice are also possible. Our findings indicate that this water intoxication model is effective for explorations of new brain edema treatments. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 78 2 2024 The Roles of Neuropeptide Y in Respiratory Disease Pathogenesis via the Airway Immune Response 95 106 EN Junko Itano Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Katsuyuki Kiura Department of Allergy and Respiratory Medicine, Okayama University Hospital Yoshinobu Maeda Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuaki Miyahara Department of Allergy and Respiratory Medicine, Okayama University Hospital Review 10.18926/AMO/66912 The lungs are very complex organs, and the respiratory system performs the dual roles of repairing tissue while protecting against infection from various environmental stimuli. Persistent external irritation disrupts the immune responses of tissues and cells in the respiratory system, ultimately leading to respiratory disease. Neuropeptide Y (NPY) is a 36-amino-acid polypeptide and a neurotransmitter that regulates homeostasis. The NPY receptor is a seven-transmembrane-domain G-protein-coupled receptor with six subtypes (Y1, Y2, Y3, Y4, Y5, and Y6). Of these receptors, Y1, Y2, Y4, and Y5 are functional in humans, and Y1 plays important roles in the immune responses of many organs, including the respiratory system. NPY and the Y1 receptor have critical roles in the pathogenesis of asthma, chronic obstructive pulmonary disease, and idiopathic pulmonary fibrosis. The effects of NPY on the airway immune response and pathogenesis differ among respiratory diseases. This review focuses on the involvement of NPY in the airway immune response and pathogenesis of various respiratory diseases. No potential conflict of interest relevant to this article was reported.

IOP Publishing Ltd Acta Medica Okayama 0004-637X 965 1 2024 Supernova Burst and Diffuse Supernova Neutrino Background Simulator for Water Cherenkov Detectors 91 EN Fumi Nakanishi Department of Physics, Okayama University Shota Izumiyama Department of Physics, Tokyo Institute of Technology Masayuki Harada Department of Physics, Okayama University Yusuke Koshio Department of Physics, Okayama University If a Galactic core-collapse supernova explosion occurs in the future, it will be critical to rapidly alert the community to the direction of the supernova by utilizing neutrino signals in order to enable the initiation of follow-up optical observations. In addition, there is anticipation that observation of the diffuse supernova neutrino background will yield discoveries in the near future, given that experimental upper limits are approaching theoretical predictions. We have developed a new supernova event simulator for water Cherenkov neutrino detectors, such as the highly sensitive Super-Kamiokande. This simulator calculates the neutrino interaction in water for two simulation purposes, individual core-collapse supernova bursts and diffuse supernova neutrino background. Based on this simulator, we can evaluate the precision in determining the location of supernovae and estimate the expected number of events related to the diffuse supernova neutrino background in Super-Kamiokande. In this paper, we describe the basic structure of the simulator and its demonstration. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 40 15 2024 Engineering Interconnected Open-Porous Particles via Microfluidics Using Bijel Droplets as Structural Templates 8074 8082 EN Mina Masaoka Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Hiroaki Ishida Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tsutomu Ono Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Designing porous structures is key in materials science, particularly for separation, catalysis, and cell culture systems. Bicontinuous interfacially jammed emulsion gels represent a unique class of soft matter formed by kinetically arresting the separation of the spinodal decomposition phase, which is stabilized by colloidal particles with neutral wetting. This study introduces a microfluidic technique to create highly interconnected open-porous particles using bijel droplets stabilized with hexadecyltrimethylammonium bromide (CTAB)-modified silica particles. Monodisperse droplets comprising a hydrophobic monomer, water, ethanol, silica particles, and CTAB were initially formed in the microfluidic device. The diffusion of ethanol from these droplets into the continuous cyclohexane phase triggered spinodal decomposition within the droplets. The phase-separated structure within the droplets was stabilized by the CTAB-modified silica particles, and subsequent photopolymerization yielded microparticles with highly interconnected, open pores. Moreover, the influence of the ratio of the CTAB and silica particles, fluid composition, and microchannel direction on the final structure of the microparticles was explored. Our findings indicated that the phase-separated structure of the particles transitioned from oil-in-water to water-in-oil as the CTAB/silica ratio was increased. At intermediate CTAB/silica ratios, microparticles with bicontinuous structures were formed. Regardless of the fluid composition, the pore size of the particles increased with time after phase separation. However, this coarsening was arrested 15 s after droplet formation in the CTAB-modified silica particles, accompanied by a change in the particle shape from spherical to ellipsoidal. In situ observations of the bijel droplet formation revealed that the particle shape deformation is caused by the rolling of elastic bijel droplets at the bottom of the microchannel. As such, the channel setup was altered from horizontal to vertical to prevent the deformation of bijel droplets, resulting in spherical particles with open pores. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0028-0836 626 7999 2024 Oxygen-evolving photosystem II structures during S1–S2–S3 transitions 670 677 EN Hongjie Li Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Yoshiki Nakajima Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Eriko Nango Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Shigeki Owada Japan Synchrotron Radiation Research Institute Daichi Yamada Department of Picobiology, Graduate School of Life Science, University of Hyogo Kana Hashimoto Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Fangjia Luo Japan Synchrotron Radiation Research Institute Rie Tanaka RIKEN SPring-8 Center Fusamichi Akita Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Koji Kato Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Jungmin Kang RIKEN SPring-8 Center Yasunori Saitoh Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Shunpei Kishi Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Huaxin Yu Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Naoki Matsubara Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Hajime Fujii Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Michihiro Sugahara Japan Synchrotron Radiation Research Institute Mamoru Suzuki Institute for Protein Research, Osaka University Tetsuya Masuda Division of Food and Nutrition, Faculty of Agriculture, Ryukoku University Tetsunari Kimura Department of Chemistry, Graduate School of Science, Kobe University Tran Nguyen Thao Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Shinichiro Yonekura Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Long-Jiang Yu Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Takehiko Tosha RIKEN SPring-8 Center Kensuke Tono Japan Synchrotron Radiation Research Institute Yasumasa Joti Japan Synchrotron Radiation Research Institute Takaki Hatsui Japan Synchrotron Radiation Research Institute Makina Yabashi Japan Synchrotron Radiation Research Institute Minoru Kubo Department of Picobiology, Graduate School of Life Science, University of Hyogo So Iwata RIKEN SPring-8 Center Hiroshi Isobe Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Kizashi Yamaguchi Center for Quantum Information and Quantum Biology, Osaka University Michihiro Suga Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Photosystem II (PSII) catalyses the oxidation of water through a four-step cycle of Si states (i = 0–4) at the Mn4CaO5 cluster1,2,3, during which an extra oxygen (O6) is incorporated at the S3 state to form a possible dioxygen4,5,6,7. Structural changes of the metal cluster and its environment during the S-state transitions have been studied on the microsecond timescale. Here we use pump-probe serial femtosecond crystallography to reveal the structural dynamics of PSII from nanoseconds to milliseconds after illumination with one flash (1F) or two flashes (2F). YZ, a tyrosine residue that connects the reaction centre P680 and the Mn4CaO5 cluster, showed structural changes on a nanosecond timescale, as did its surrounding amino acid residues and water molecules, reflecting the fast transfer of electrons and protons after flash illumination. Notably, one water molecule emerged in the vicinity of Glu189 of the D1 subunit of PSII (D1-E189), and was bound to the Ca2+ ion on a sub-microsecond timescale after 2F illumination. This water molecule disappeared later with the concomitant increase of O6, suggesting that it is the origin of O6. We also observed concerted movements of water molecules in the O1, O4 and Cl-1 channels and their surrounding amino acid residues to complete the sequence of electron transfer, proton release and substrate water delivery. These results provide crucial insights into the structural dynamics of PSII during S-state transitions as well as O–O bond formation. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0020-1693 564 2024 Synthesis and characterization of iron(II) complex with unsymmetrical heterocyclic (2-pyridyl)(4-imidazolyl)azine 121937 EN Kennedy Mawunya Hayibor Yukinari Sunatsuki Takayoshi Suzuki A new iron(II) complex bearing unsymmetrical azine, [Fe(HLH)2](PF6)2·H2O·MeCN (HLH = 2-pyridylmethylidenehydrazono(4-imidazolyl)methane), was synthesized exclusively by a reaction of 2-pyridine carboxaldehyde, 1H-imidazole-4-carboxaldehyde, hydrazine monohydrate and FeCl2·4H2O (in a molar ratio of 2:2:2:1) in methanol, followed by the addition of an aqueous NH4PF6 solution. It was characterized using spectroscopic techniques, elemental analysis, magnetic measurement, and cyclic voltammetry. The molecular and crystal structure of the compound was revealed by X-ray analysis, where an iron(II) ion was surrounded by two HLH azines with a planar E(py),Z(im) conformation, and tridentate κ3N,N’,N” coordination mode, forming a monomeric six-coordinated and diamagnetic complex. The complex cations were linked by water molecules via intermolecular hydrogen-bonding interactions between the imidazole N−H and the neighboring uncoordinated azine-N atom, forming a 1D chain structure. The selective formation of this unsymmetrical azine (HLH) from a stoichiometric mixture of the components would result from the steric preference of the five- and six-membered chelate rings by the 2-pyridyl and 4-imidazolyl azine moieties, respectively, with the E(py),Z(im) configuration. No potential conflict of interest relevant to this article was reported.

Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH) Acta Medica Okayama 1882-3416 18 1 2024 Efficient agricultural monitoring: a methodology for assessing individual farmer adherence to rice-planting schedule for tertiary irrigation system under the Muda Irrigation Scheme using Earth observation datasets 14 21 EN Aliya Mhd Zahir Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Toshitsugu Moroizumi Graduate School of Environmental and Life Science, Okayama University The tertiary irrigation system (TIS) was designed for the Muda Irrigation Scheme (MIS) to distribute irrigation water to farmers' fields to ensure the reliability of water supply for cultivating rice paddies twice a year. Variability in farming practices, influenced by farmer autonomy along the tertiary canal adds complexity and uncertainty to adherence monitoring. Traditional on -site data collection methods are limited in scope and efficiency, whereas Earth observation (EO) enables continuous monitoring. In this study, we introduced a methodology that uses EO datasets to monitor individual field adherence to rice -planting schedules under TIS. These tools improve the monitoring of rice -planting schedule adherence by identifying non -adherent fields for further countermeasures. This study highlights the potential use of EO datasets and advanced data processing techniques for efficient agricultural monitoring. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2041-1723 14 1 2023 Structural insights into photosystem II supercomplex and trimeric FCP antennae of a centric diatom Cyclotella meneghiniana 8164 EN Songhao Zhao Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Lili Shen Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Xiaoyi Li Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Qiushuang Tao Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Zhenhua Li Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Caizhe Xu Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Cuicui Zhou Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Yanyan Yang Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Min Sang China National Botanical Garden Guangye Han Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Long-Jiang Yu Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Tingyun Kuang Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Jian-Ren Shen Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University Wenda Wang Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences Diatoms are dominant marine algae and contribute around a quarter of global primary productivity, the success of which is largely attributed to their photosynthetic capacity aided by specific fucoxanthin chlorophyll-binding proteins (FCPs) to enhance the blue-green light absorption under water. We purified a photosystem II (PSII)-FCPII supercomplex and a trimeric FCP from Cyclotella meneghiniana (Cm) and solved their structures by cryo-electron microscopy (cryo-EM). The structures reveal detailed organizations of monomeric, dimeric and trimeric FCP antennae, as well as distinct assemblies of Lhcx6_1 and dimeric FCPII-H in PSII core. Each Cm-PSII-FCPII monomer contains an Lhcx6_1, an FCP heterodimer and other three FCP monomers, which form an efficient pigment network for harvesting energy. More diadinoxanthins and diatoxanthins are found in FCPs, which may function to quench excess energy. The trimeric FCP contains more chlorophylls c and fucoxanthins. These diversified FCPs and PSII-FCPII provide a structural basis for efficient light energy harvesting, transfer, and dissipation in C. meneghiniana. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 1083-351X 299 7 2023 Structural insights into the action mechanisms of artificial electron acceptors in photosystem II 104839 EN Shinji Kamada Faculty of Science, Okayama University Yoshiki Nakajima Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University Photosystem II (PSII) utilizes light energy to split water, and the electrons extracted from water are transferred to QB, a plastoquinone molecule bound to the D1 subunit of PSII. Many artificial electron acceptors (AEAs) with molecular structures similar to that of plastoquinone can accept electrons from PSII. However, the molecular mechanism by which AEAs act on PSII is unclear. Here, we solved the crystal structure of PSII treated with three different AEAs, 2,5-dibromo-1,4-benzoquinone, 2,6dichloro-1,4-benzoquinone, and 2-phenyl-1,4-benzoquinone, at 1.95 to 2.10 angstrom resolution. Our results show that all AEAs substitute for QB and are bound to the QB-binding site (QB site) to receive electrons, but their binding strengths are different, resulting in differences in their efficiencies to accept electrons. The acceptor 2-phenyl-1,4-benzoquinone binds most weakly to the QB site and showed the highest oxygen-evolving activity, implying a reverse relationship between the binding strength and oxygen-evolving activity. In addition, a novel quinonebinding site, designated the QD site, was discovered, which is located in the vicinity of QB site and close to QC site, a binding site reported previously. This QD site is expected to play a role as a channel or a storage site for quinones to be transported to the QB site. These results provide the structural basis for elucidating the actions of AEAs and exchange mechanism of QB in PSII and also provide information for the design of more efficient electron acceptors. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 78 1 2024 Quantitative Assessment of the Heat Transfer Capacity of Ice Bags and their Cooling Effects on the Skin Surface and Core Temperature 53 61 EN Yukiko Ichikawa Department of Nursing Science, Faculty of Health and Welfare Science, Okayama Prefectural University Tetsuya Ogino Department of Nursing Science, Faculty of Health and Welfare Science, Okayama Prefectural University Original Article 10.18926/AMO/66671 Ice bags are frequently used in medical care settings for pain relief, comfort, and in some cases, whole-body cooling. This study quantifies heat energy transfer capacity of ice bags and evaluates their cooling effects on body temperature. Forty-eight healthy adults in their 20s were recruited. An ice bag wrapped in two layers of dry towel was applied to the forehead, neck, or palm of each participant for 10 min. The skin surface temperature, heat flow, and core temperature were recorded during the cooling and non-cooling periods, with energy transfer calculated by integrating heat flow over time. Over the non-cooling period, 31.4-53.6 kJ·m-2 of energy was dissipated over 10 min, whereas during the cooling period, the range increased to 180.0-218.7 kJ·m-2 over 10 min. Skin surface temperature decreased by 3.2-5.7°C, whereas core temperature was unchanged. Ice bag use augmented energy transfer by about 150-180 kJ·m-2 over 10 min, but this was insufficient for rapid whole body cooling due to the small skin-surface area in contact with the ice bag. The measured energy transfer indicated that topical ice bag application absorbs insufficient energy to affect core temperature. Quantitative assessment of energy transfer was shown to inform the safe and appropriate use of thermotherapy. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0343-8651 81 3 2024 Mutational analysis of the transmembrane α4-helix of Bacillus thuringiensis mosquito-larvicidal Cry4Aa toxin 80 EN Hirokazu Takahashi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mami Asakura Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toru Ide Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tohru Hayakawa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Cry4Aa, produced by Bacillus thuringiensis subsp. israelensis, exhibits specific toxicity to larvae of medically important mosquito genera. Cry4Aa functions as a pore-forming toxin, and a helical hairpin (α4-loop-α5) of domain I is believed to be the transmembrane domain that forms toxin pores. Pore formation is considered to be a central mode of Cry4Aa action, but the relationship between pore formation and toxicity is poorly understood. In the present study, we constructed Cry4Aa mutants in which each polar amino acid residues within the transmembrane α4 helix was replaced with glutamic acid. Bioassays using Culex pipiens mosquito larvae and subsequent ion permeability measurements using symmetric KCl solution revealed an apparent correlation between toxicity and toxin pore conductance for most of the Cry4Aa mutants. In contrast, the Cry4Aa mutant H178E was a clear exception, almost losing its toxicity but still exhibiting a moderately high conductivity of about 60% of the wild-type. Furthermore, the conductance of the pore formed by the N190E mutant (about 50% of the wild-type) was close to that of H178E, but the toxicity was significantly higher than that of H178E. Ion selectivity measurements using asymmetric KCl solution revealed a significant decrease in cation selectivity of toxin pores formed by H178E compared to N190E. Our data suggest that the toxicity of Cry4Aa is primarily pore related. The formation of toxin pores that are highly ion-permeable and also highly cation-selective may enhance the influx of cations and water into the target cell, thereby facilitating the eventual death of mosquito larvae. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 2186-7755 113 2024 Effect of seed cold PEG-priming and subsequent long storage on germination, growth and flowering of Eustoma grandiflorum（Raf.）Shinn ʻExe Lavenderʼ 7 10 EN Thao Thu Phan Graduate School of Environmental and Life Science, Okayama University Keigo Fukushima Hiroshima Prefectural Technology Research Institute, Agricultural Technology Research Center Yoshiyuki Tanaka Graduate School of Environmental and Life Science, Okayama University Ken-ichiro Yasuba Graduate School of Environmental and Life Science, Okayama University Yuichi Yoshida Graduate School of Environmental and Life Science, Okayama University Tanjuro Goto Graduate School of Environmental and Life Science, Okayama University Cold wet treatment is frequently applied to Eustoma seeds to enhance the bolting rate of plants grown under high temperatures. Our previous study indicated that cold PEG‒primed Eustoma seeds could maintain their germination rate and bolting rate even after being re‒dried for 30days and grown under high temperatures. The present study aimed to investigate whether prolonged storage after cold PEG‒priming affect the germination, growth, and flowering of Eustoma ‘Exe Lavender’ seedling. Seeds were initially cold‒primed with water or PEG‒6000 at ‒1.5 MPa for 5 weeks at 10°C in the dark and were then subjected to re‒drying and storage for 30, 60, 90 and 360days at 10°C. After 360days of storage, cold PEG‒primed seeds germinated earlier and more effectively than cold hydro‒primed seeds. Compared to the results after 30days of storage, plants grown from 360days exhibited similar bolting rate, days to bolting, bolting node and flowering rate, cut flower length and number of flower node. These results suggest that ‘Exe Lavender’ seeds can germinate and develop well even after 360days of storage and under high temperature conditions when subjected to cold PEG‒6000 treatment. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1549-9596 64 2 2023 pSPICA Force Field Extended for Proteins and Peptides 532 542 EN Yusuke Miyazaki Research Institute for Interdisciplinary Science, Okayama University Wataru Shinoda Research Institute for Interdisciplinary Science, Okayama University Many coarse-grained (CG) molecular dynamics (MD) studies have been performed to investigate biological processes involving proteins and lipids. CG force fields (FFs) in these MD studies often use implicit or nonpolar water models to reduce computational costs. CG-MD using water models cannot properly describe electrostatic screening effects owing to the hydration of ionic segments and thus cannot appropriately describe molecular events involving water channels and pores through lipid membranes. To overcome this issue, we developed a protein model in the pSPICA FF, in which a polar CG water model showing the proper dielectric response was adopted. The developed CG model greatly improved the transfer free energy profiles of charged side chain analogues across the lipid membrane. Application studies on melittin-induced membrane pores and mechanosensitive channels in lipid membranes demonstrated that CG-MDs using the pSPICA FF correctly reproduced the structure and stability of the pores and channels. Furthermore, the adsorption behavior of the highly charged nona-arginine peptides on lipid membranes changed with salt concentration, indicating the pSPICA FF is also useful for simulating protein adsorption on membrane surfaces. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1936-0851 18 1 2023 Close-Packed Ices in Nanopores 347 354 EN Kenji Mochizuki Department of Chemistry, Zhejiang University Yuji Adachi Graduate School of Natural Sciences, Okayama University Kenichiro Koga Department of Chemistry, Okayama University Water molecules in any of the ice polymorphs organize themselves into a perfect four-coordinated hydrogen-bond network at the expense of dense packing. Even at high pressures, there seems to be no way to reconcile the ice rules with the close packing. Here, we report several close-packed ice phases in carbon nanotubes obtained from molecular dynamics simulations of two different water models. Typically they are in plastic states at high temperatures and are transformed into the hydrogen-ordered ice, keeping their close-packed structures at lower temperatures. The close-packed structures of water molecules in carbon nanotubes are identified with those of spheres in a cylinder. We present design principles of hydrogen-ordered, close-packed structures of ice in nanotubes, which suggest many possible dense ice forms with or without nonzero polarization. In fact, some of the simulated ices are found to exhibit ferroelectric ordering upon cooling. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0003-6951 123 23 2023 Water/ice mixture- and freezing-front motion in a non-isothermal liquid bridge 231601 EN Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kodai Okano School of Engineering, Okayama University Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University We experimentally investigate the water/ice mixture- and freezing-front behavior in a water liquid bridge under isothermal and non-isothermal conditions. We find rapid propagation, temporary suspension, and regression of the water/ice mixture front, and finally, it merges with the freezing front when part of the liquid bridge is higher than the freezing temperature. However, freezing-front propagation follows dendritic ice formation, and a protrusion forms at the middle of the liquid bridge as long as the whole liquid bridge is lower than the freezing temperature. We explain those phenomena by quasi-stationary heat-transfer considerations. No potential conflict of interest relevant to this article was reported.

eLife Sciences Publications Acta Medica Okayama 2050-084X 12 2023 Characterization of tryptophan oxidation affecting D1 degradation by FtsH in the photosystem II quality control of chloroplasts RP88822 EN Yusuke Kato Institute of Plant Science and Resources (IPSR), Okayama University Hiroshi Kuroda Research Institute for Interdisciplinary Science, Okayama University Shin-Ichiro Ozawa Institute of Plant Science and Resources (IPSR), Okayama University Keisuke Saito Research Center for Advanced Science and Technology, The University of Tokyo Vivek Dogra Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences Martin Scholz Institute of Plant Biology and Biotechnology, University of Münster Guoxian Zhang Institute of Plant Science and Resources (IPSR), Okayama University Catherine de Vitry Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université Pierre et Marie Curie Hiroshi Ishikita Research Center for Advanced Science and Technology, The University of Tokyo Chanhong Kim Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences Michael Hippler Institute of Plant Science and Resources (IPSR), Okayama University Yuichiro Takahashi Research Institute for Interdisciplinary Science, Okayama University Wataru Sakamoto Institute of Plant Science and Resources (IPSR), Okayama University Photosynthesis is one of the most important reactions for sustaining our environment. Photosystem II (PSII) is the initial site of photosynthetic electron transfer by water oxidation. Light in excess, however, causes the simultaneous production of reactive oxygen species (ROS), leading to photo-oxidative damage in PSII. To maintain photosynthetic activity, the PSII reaction center protein D1, which is the primary target of unavoidable photo-oxidative damage, is efficiently degraded by FtsH protease. In PSII subunits, photo-oxidative modifications of several amino acids such as Trp have been indeed documented, whereas the linkage between such modifications and D1 degradation remains elusive. Here, we show that an oxidative post-translational modification of Trp residue at the N-terminal tail of D1 is correlated with D1 degradation by FtsH during high-light stress. We revealed that Arabidopsis mutant lacking FtsH2 had increased levels of oxidative Trp residues in D1, among which an N-terminal Trp-14 was distinctively localized in the stromal side. Further characterization of Trp-14 using chloroplast transformation in Chlamydomonas indicated that substitution of D1 Trp-14 to Phe, mimicking Trp oxidation enhanced FtsH-mediated D1 degradation under high light, although the substitution did not affect protein stability and PSII activity. Molecular dynamics simulation of PSII implies that both Trp-14 oxidation and Phe substitution cause fluctuation of D1 N-terminal tail. Furthermore, Trp-14 to Phe modification appeared to have an additive effect in the interaction between FtsH and PSII core in vivo. Together, our results suggest that the Trp oxidation at its N-terminus of D1 may be one of the key oxidations in the PSII repair, leading to processive degradation by FtsH. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1436-2228 25 6 2023 Nuclear Transformation of the Marine Pennate Diatom Nitzschia sp. Strain NIES-4635 by Multi-Pulse Electroporation 1208 1219 EN Koki Okada Graduate School of Environmental and Life Science, Okayama University Yu Morimoto Graduate School of Environmental and Life Science, Okayama University Yukine Shiraishi Graduate School of Environmental and Life Science, Okayama University Takashi Tamura Faculty of Environmental, Life, Natural Science and Technology, Okayama University Shigeki Mayama The Advanced Support Center for Science Teachers, Tokyo Gakugei University Takashi Kadono Faculty of Agriculture and Marine Science, Kochi University Masao Adachi Faculty of Agriculture and Marine Science, Kochi University Kentaro Ifuku Graduate School of Agriculture, Kyoto University Michiko Nemoto Faculty of Environmental, Life, Natural Science and Technology, Okayama University Nitzschia is one of the largest genera of diatoms found in a range of aquatic environments, from freshwater to seawater. This genus contains evolutionarily and ecologically unique species, such as those that have lost photosynthetic capacity or those that live symbiotically in dinoflagellates. Several Nitzschia species have been used as indicators of water pollution. Recently, Nitzschia species have attracted considerable attention in the field of biotechnology. In this study, a transformation method for the marine pennate diatom Nitzschia sp. strain NIES-4635, isolated from the coastal Seto Inland Sea, was established. Plasmids containing the promoter/terminator of the fucoxanthin chlorophyll a/c binding protein gene (fcp, or Lhcf) derived from Nitzschia palea were constructed and introduced into cells by multi-pulse electroporation, resulting in 500 μg/mL nourseothricin-resistant transformants with transformation frequencies of up to 365 colonies per 108 cells. In addition, when transformation was performed using a new plasmid containing a promoter derived from a diatom-infecting virus upstream of the green fluorescent protein gene (gfp), 44% of the nourseothricin-resistant clones exhibited GFP fluorescence. The integration of the genes introduced into the genomes of the transformants was confirmed by Southern blotting. The Nitzschia transformation method established in this study will enable the transformation this species, thus allowing the functional analysis of genes from the genus Nitzschia, which are important species for environmental and biotechnological development. No potential conflict of interest relevant to this article was reported.

岡山大学文明動態学研究所 Acta Medica Okayama 2436-8326 3 2024 明治期における水利・洪水と千住中組高尾家―見沼代用水を事例に― 79 91 EN Shoji MIMURA National Defense Academy of Japan 特集：災害と文明・地域社会 (Special Issue: Disasters, civilization, and local society) 10.18926/66194 This paper examines the maintenance work of the Minuma Substitute Canal by the Meiji Government and how Noriyoshi Takao who lived at Senjū-nakagumi was involved in it. In the 1880s, when the cost of maintaining the Minuma Substitute Canal was shifted from government expenditures to private ones, the early modern water usage system was on the verge of being converted to a modern one. This meant that the system, which was based on villages or ryō (領), transformed into one based on individuals, especially landowners. The village served as a cost-sharing unit during the Meiji period. Ryō (領) were operated in the downstream water of the Minuma Substitute Canal where there were no critical structures. However, districts (郡) supervised the water usage of ryō, creating a multilayered local community in terms of water usage. No potential conflict of interest relevant to this article was reported.

Informa UK Limited Acta Medica Okayama 0737-3937 42 2 2023 Flavor retention characteristics of amorphous solid dispersion of flavors, prepared by vacuum-foam- and spray-drying under different conditions 227 237 EN Yuna Nitta Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Haruna Sato Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Rina Yamamoto Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Hiroyuki Imanaka Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Naoyuki Ishida Department of Chemical Engineering and Material Sciences, Faculty of Science and Engineering, Doshisha University Koreyoshi Imamura Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University We investigated the powderization of flavoring substances, using an amorphous solid dispersion (ASD) technique, in which hydrophobic molecules are separately embedded in a water-soluble carrier matrix. Six flavors, five carrier forming materials (polyvinylpyrrolidone/disaccharides), two solvents (methanol/ethanol) and two drying methods (vacuum-foam-/spray-drying) were employed. The drying conditions for the two drying processes were first examined, and under the optimal drying conditions, various flavor-carrier combinations and compositions of ASD samples were prepared and their flavor retention after drying and during storage under a vacuum were compared. Results demonstrated that flavor loss during drying and storage was minimized when the material was vacuum-foam-dried with polyvinylpyrrolidone. Vacuum-foam-drying in the presence of α-maltose or palatinose also resulted in a greater retention of flavor during drying and storage than a typical O/W emulsification-based powderization. These findings suggest that the ASD-based powderization of flavoring materials is a feasible alternative to the currently used produces. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2075-4418 13 18 2023 MicroRNAs as Biomarkers and Therapeutic Targets for Acute Kidney Injury 2893 EN Kenji Tsuji Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroyuki Nakanoh Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhiko Fukushima Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kitamura Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Jun Wada Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Acute kidney injury (AKI) is a clinical syndrome where a rapid decrease in kidney function and/or urine output is observed, which may result in the imbalance of water, electrolytes and acid base. It is associated with poor prognosis and prolonged hospitalization. Therefore, an early diagnosis and treatment to avoid the severe AKI stage are important. While several biomarkers, such as urinary L-FABP and NGAL, can be clinically useful, there is still no gold standard for the early detection of AKI and there are limited therapeutic options against AKI. miRNAs are non-coding and single-stranded RNAs that silence their target genes in the post-transcriptional process and are involved in a wide range of biological processes. Recent accumulated evidence has revealed that miRNAs may be potential biomarkers and therapeutic targets for AKI. In this review article, we summarize the current knowledge about miRNAs as promising biomarkers and potential therapeutic targets for AKI, as well as the challenges in their clinical use. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2079-6382 12 11 2023 Novel Iron Chelators, Super-Polyphenols, Show Antimicrobial Effects against Cariogenic Streptococcus mutans 1562 EN Yuki Shinoda-Ito Department of Pathophysiology-Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazuhiro Omori Department of Pathophysiology-Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takashi Ito Center for Innovative Clinical Medicine, Okayama University Hospital Masaaki Nakayama Department of Oral Microbiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Atsushi Ikeda Department of Periodontics & Endodontics, Division of Dentistry, Okayama University Hospital Masahiro Ito Department of Pathophysiology-Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shogo Takashiba Department of Pathophysiology-Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Dental caries are an oral infectious disease that can affect human health both orally and systemically. It remains an urgent issue to establish a novel antibacterial method to prevent oral infection for a healthy life expectancy. The aim of this study was to evaluate the inhibitory effects of novel iron chelators, super-polyphenols (SPs), on the cariogenic bacterium Streptococcus mutans, in vitro. SPs were developed to reduce the side effects of iron chelation therapy and were either water-soluble or insoluble depending on their isoforms. We found that SP6 and SP10 inhibited bacterial growth equivalent to povidone-iodine, and viability tests indicated that their effects were bacteriostatic. These results suggest that SP6 and SP10 have the potential to control oral bacterial infections such as Streptococcus mutans. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1463-9076 25 45 2023 Solvation free energies of alcohols in water: temperature and pressure dependences 31107 31117 EN Aoi Taira Department of Chemistry, Faculty of Science, Okayama University Ryuichi Okamoto Graduate School of Information Science, University of Hyogo Tomonari Sumi Department of Chemistry, Faculty of Science, Okayama University Kenichiro Koga Department of Chemistry, Faculty of Science, Okayama University Solvation free energies μ* of amphiphilic species, methanol and 1,2-hexanediol, are obtained as a function of temperature or pressure based on molecular dynamics simulations combined with efficient free-energy calculation methods. In general, μ* of an amphiphile can be divided into Image ID:d3cp03799a-t1.gif and Image ID:d3cp03799a-t2.gif, the nonpolar and electrostatic contributions, and the former is further divided into Image ID:d3cp03799a-t3.gif and Image ID:d3cp03799a-t4.gif which are the work of cavity formation process and the free energy change due to weak, attractive interactions between the solute molecule and surrounding solvent molecules. We demonstrate that μ* of the two amphiphilic solutes can be obtained accurately using a perturbation combining method, which relies on the exact expressions for Image ID:d3cp03799a-t5.gif and Image ID:d3cp03799a-t6.gif and requires no simulations of intermediate systems between the solute with strong, repulsive interactions and the solute with the van der Waals and electrostatic interactions. The decomposition of μ* gives us several physical insights including that μ* is an increasing function of T due to Image ID:d3cp03799a-t7.gif, that the contributions of hydrophilic groups to the temperature dependence of μ* are additive, and that the contribution of the van der Waals attraction to the solvation volume is greater than that of the electrostatic interactions. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2023 Application of amorphous sugar matrix dried from alcohol to solid dispersion of hydrophobic drug and its physicochemical characteristics EN Koji TAKEDA Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 77 5 2023 Low Patient Weight and Long Intubation Time Are Key Factors for Pain during Colonoscopy 471 478 EN Shohei Oka Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Keita Harada Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shumpei Yamamoto Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Eriko Yasutomi Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shoko Igawa Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masayasu Ohmori Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Mami Hirai Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasushi Yamasaki Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshihiro Inokuchi Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hideaki Kinugasa Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiro Takahara Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Sakiko Hiraoka Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroyuki Okada Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/65969 Although the clinical usefulness of colonoscopy has been established, the procedure remains painful for many patients. This study was designed to clarify the factors predicting colonoscopy-related pain. We evaluated 283 consecutive patients who completed a first-ever, total colonoscopy without sedatives or analgesics. The severity of pain symptoms was evaluated by a numeric rating scale (NRS) in a questionnaire immediately after the colonoscopy. Patient backgrounds and endoscopic findings were analyzed to evaluate their association with pain. Out of 283 patients, 53 scored their pain 0-1 on the NRS while 48 scored it 6-10. We defined the colonoscopies of the former and latter patients as painless and painful, respectively, and compared the two. Multivariate analyses revealed that low body weight (OR 4.95, 95%CI 1.89-12.99) and longer intubation time (OR 3.63, 95%CI 1.46-9.03) were significant risk factors for painful colonoscopy. To identify factors contributing to the increased intubation time, we divided subjects into short- and long-intubation-time groups based on a median insertion time of 7 min. Older age (OR 2.28, 95%CI 1.31-3.98), previous abdominal surgery (OR 1.93, 95%CI 1.13-3.32) and findings of invasive cancer (OR 10.90, 95%CI 1.34-88.90) were significant factors for longer intubation time. No potential conflict of interest relevant to this article was reported.

American Association for the Advancement of Science (AAAS) Acta Medica Okayama 2375-2548 8 12 2022 Structure and dynamics of Odinarchaeota tubulin and the implications for eukaryotic microtubule evolution eabm2225 EN Caner Akıl Research Institute for Interdisciplinary Science, Okayama University Samson Ali Research Institute for Interdisciplinary Science, Okayama University Linh T. Tran Research Institute for Interdisciplinary Science, Okayama University Jérémie Gaillard University of Grenoble-Alpes, CEA, CNRS, INRA, Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab Wenfei Li National Laboratory of Solid State Microstructure, Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University Kenichi Hayashida Cellular and Structural Physiology Institute (CeSPI), Nagoya University Mika Hirose Institute for Protein Research, Osaka University Takayuki Kato Institute for Protein Research, Osaka University Atsunori Oshima Cellular and Structural Physiology Institute (CeSPI), Nagoya University Kosuke Fujishima Tokyo Institute of Technology, Earth-Life Science Institute (ELSI) Laurent Blanchoin University of Grenoble-Alpes, CEA, CNRS, INRA, Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab Akihiro Narita Division of Biological Science, Graduate School of Science, Nagoya University Robert C. Robinson Research Institute for Interdisciplinary Science, Okayama University Tubulins are critical for the internal organization of eukaryotic cells, and understanding their emergence is an important question in eukaryogenesis. Asgard archaea are the closest known prokaryotic relatives to eukaryotes. Here, we elucidated the apo and nucleotide-bound x-ray structures of an Asgard tubulin from hydrothermal living Odinarchaeota (OdinTubulin). The guanosine 5′-triphosphate (GTP)–bound structure resembles a microtubule protofilament, with GTP bound between subunits, coordinating the “+” end subunit through a network of water molecules and unexpectedly by two cations. A water molecule is located suitable for GTP hydrolysis. Time course crystallography and electron microscopy revealed conformational changes on GTP hydrolysis. OdinTubulin forms tubules at high temperatures, with short curved protofilaments coiling around the tubule circumference, more similar to FtsZ, rather than running parallel to its length, as in microtubules. Thus, OdinTubulin represents an evolutionary stage intermediate between prokaryotic FtsZ and eukaryotic microtubule-forming tubulins. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2046-2069 12 6 2022 Flame retardance-donated lignocellulose nanofibers (LCNFs) by the Mannich reaction with (amino-1,3,5-triazinyl)phosphoramidates and their properties 3300 3308 EN Fumiaki Ono Okayama Biomass Innovation Creative Center Takumi Okihara Graduate School of Natural Science and Technology, Okayama University Noboru Osaka Faculty of Science, Okayama University of Science Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Science, Okayama University Dental School Yuji Kameoka Marubishi Oil Chemical Co., Ltd Akira Ishikawa Marubishi Oil Chemical Co., Ltd Hironari Ooki Gen Gen Corporation Takumi Ito Gen Gen Corporation Daisuke Todome Faculty of Science, Okayama University of Science Shinya Uemoto Okayama Biomass Innovation Creative Center Mitsuaki Furutani Okayama Biomass Innovation Creative Center Tsutomu Inokuchi Graduate School of Natural Science and Technology, Okayama University Kenji Okada Department of Life Science, Kurashiki University of Science & the Arts Nitrogen/phosphorus-containing melamines (NPCM), a durable flame-retardant, were prepared by the successive treatment of ArOH (Ar = BrnC6H5−n, n = 0, 1, 2, and 3) with POCl3 and melamine monomer. The prepared flame-retardants were grafted through the CH2 unit to lignocellulose nanofibers (LCNFs) by the Mannich reaction. The resulting three-component products were characterized using FT-IR (ATR) and EA. The thermal behavior of the NPCM-treated LCNF fabric samples was determined using TGA and DSC analyses, and their flammability resistances were evaluated by measuring their Limited Oxygen Index (LOI) and the UL-94V test. A multitude of flame retardant elements in the fabric samples increased the LOI values as much as 45 from 20 of the untreated LCNFs. Moreover, the morphology of both the NPCM-treated LCNFs and their burnt fabrics was studied with a scanning electron microscope (SEM). The heat release lowering effect of the LCNF fabric against the water-based paint was observed with a cone calorimeter. Furthermore, the mechanical properties represented as the tensile strength of the NPCM-treated LCNF fabrics revealed that the increase of the NPCM content in the PP-composites led to an increased bending strength with enhancing the flame-retardance. No potential conflict of interest relevant to this article was reported.

Japanese Society for Medical and Biological Engineering Acta Medica Okayama 2187-5219 11 2022 Skin Electrical Impedance Model for Evaluation of the Thickness and Water Content of the Stratum Corneum 98 108 EN Osamu Uehara Medical Engineering Laboratory, ALCARE CO., Ltd. Toshimasa Kusuhara Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Kenichi Matsuzaki Medical Engineering Laboratory, ALCARE CO., Ltd. Yoshitake Yamamoto Okayama University Takao Nakamura Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Deterioration of the skin barrier function causes symptoms such as allergies because various chemical substances may enter the human body. Quantitative evaluation of the thickness and water content of the stratum corneum is useful as a measure of the skin barrier function in domains such as dermatology, nursing science, and cosmetics development. The stratum corneum is responsible for most of the skin barrier function, and two factors—the thickness and water content of the stratum corneum—are thus important. In this paper, the stratum corneum is regarded as a parallel model of resistance and capacitance. From measurements of the electrical impedance of the skin, we propose a new model for simultaneous estimation of the thickness and water content of the stratum corneum conventionally measured by a confocal laser scanning microscope and a confocal Raman spectrometer, respectively, and we discuss the results of the measurements. The electrical impedance of the skin was measured using a device that we developed. The measurement began 3 seconds after the electrodes on the measurement head of the device came into contact with the skin, and parameters including the impedance, which was obtained by applying an alternating current signal at two frequencies, were measured. We measured the thickness and water content of the stratum corneum using confocal laser microscopy and confocal Raman spectroscopy, respectively; investigated the relationship of the thickness and water content of the stratum corneum with the electrical impedance of the skin; and established a new potential model for estimating the thickness and water content of the stratum corneum from the parallel resistance and capacitance. The correlation coefficients of the verification data were 0.931 and 0.776, respectively; and the root-mean-squared error of the thickness of the stratum corneum was 2.3 µm, while the root-mean-squared error of the water content at the surface of the stratum corneum was 5.4 points. These findings indicate the feasibility of quantitative evaluation of the thickness and water content of the stratum corneum by measuring skin electrical impedance. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0021-9673 1706 2023 Separation and fractionation of glutamic acid and histidine via origami isoelectric focusing 464247 EN Kaewta Danchana Department of Chemistry, Okayama University Nayu Yamashita Department of Chemistry, Okayama University Mika I. Umeda Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University We demonstrated the fractionation of two amino acids, glutamic acid and histidine, separated via isoelectric focusing (IEF) on filter paper folded and stacked in an origami fashion. Channels for electrophoresis were fabricated as circular zones acquired via wax printing onto the filter paper. An ampholyte solution with amphiphilic samples was deposited on all the circle zones, which was followed by folding to form the electrophoresis channels. IEF was achieved by applying an electrical potential between the anodic and cathodic chambers filled with phosphoric acid and sodium hydroxide solutions, respectively. A pH gradient was formed using either a wide-range ampholyte with a pH of 3 to 10 or a narrow-range version with a pH of 5 to 8, which was confirmed by adding pH indicators to each layer. The origami IEF was used to separate the amino acids, glutamic acid and histidine, by mixing with the ampholytes, which were deposited on the layers. The components in each layer were extracted with water and measured by high-performance liquid chromatography using pre-column derivatization with dansyl chloride. The results indicated that the focus for glutamic acid and that for histidine were at different layers, according to their isoelectric points. The origami isoelectric focusing achieved the fractionation of amino acids in less than 3 min using voltage as low as 30 V. No potential conflict of interest relevant to this article was reported.

IOP Publishing Ltd Acta Medica Okayama 2041-8205 951 2 2023 Search for Astrophysical Electron Antineutrinos in Super-Kamiokande with 0.01% Gadolinium-loaded Water L27 EN M. Harada Department of Physics, Okayama University We report the first search result for the flux of astrophysical electron antineutrinos for energies O(10) MeV in the gadolinium-loaded Super-Kamiokande (SK) detector. In 2020 June, gadolinium was introduced to the ultrapure water of the SK detector in order to detect neutrons more efficiently. In this new experimental phase, SK-Gd, we can search for electron antineutrinos via inverse beta decay with efficient background rejection thanks to the high efficiency of the neutron tagging technique. In this paper, we report the result for the initial stage of SK-Gd, during 2020 August 26, and 2022 June 1 with a 22.5 x 552 kton center dot day exposure at 0.01% Gd mass concentration. No significant excess over the expected background in the observed events is found for the neutrino energies below 31.3 MeV. Thus, the flux upper limits are placed at the 90% confidence level. The limits and sensitivities are already comparable with the previous SK result with pure water (22.5 x 2970 kton center dot day) owing to the enhanced neutron tagging. Operation with Gd increased to 0.03% started in 2022 June. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 77 4 2023 Association between Radon Hot Spring Bathing and Health Conditions: A Cross-Sectional Study in Misasa, Japan 387 394 EN Takahiro Kataoka Department of Radiological Technology, Okayama University Graduate School of Health Sciences Hiroshi Habu Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ayumi Tanaka Department of Radiological Technology, Okayama University Graduate School of Health Sciences Shota Naoe Department of Radiological Technology, Okayama University Graduate School of Health Sciences Kaito Murakami Department of Radiological Technology, Okayama University Graduate School of Health Sciences Yuki Fujimoto Department of Radiological Technology, Okayama University Graduate School of Health Sciences Ryohei Yukimine Department of Radiological Technology, Okayama University Graduate School of Health Sciences Soshi Takao Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Fumihiro Mitsunobu Department of Longevity and Social Medicine (Geriatrics), Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takashi Yorifuji Department of Epidemiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kiyonori Yamaoka Department of Radiological Technology, Okayama University Graduate School of Health Sciences Original Article 10.18926/AMO/65749 No epidemiological studies have examined the health effects of daily bathing in radon hot springs. In this cross-sectional study, we investigated the associations between radon hot spring bathing and health conditions. The target population was 5,250 adults ≥ 20 years old in the town of Misasa, Japan. We collected information about the participants’ bathing habits and alleviation of a variety of disease symptoms, and their self-rated health (SRH). Unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CI) were calculated. In both the adjusted and unadjusted models of hypertension, significant associations between the > 1×/week hot spring bathing and the alleviation of hypertension symptoms were observed compared to the group whose hot spring bathing was <1×/week: adjusted model, OR 5.40 (95%CI: 1.98-14.74); unadjusted model, 3.67 (1.50-8.99) and for gastroenteritis: adjusted model, 9.18 (1.15-72.96); unadjusted model, 7.62 (1.59-36.49). Compared to the no-bathing group, higher SRH was significantly associated with both bathing < 1×/week: unadjusted model, 2.27 (1.53-3.37) and > 1×/week: adjusted model, 1.91 (1.15-3.19). These findings suggest that bathing in radon hot springs is associated with higher SRH and the alleviation of hypertension and gastroenteritis. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-3921 12 7 2023 Combined Effect of Salicylic Acid and Proline Mitigates Drought Stress in Rice (Oryza sativa L.) through the Modulation of Physiological Attributes and Antioxidant Enzymes 1438 EN Tahmina Akter Urmi Department of Soil Science, Faculty of Agriculture, Bangladesh Agricultural University Md. Moshiul Islam Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kamrun Naher Zumur Department of Agronomy, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University Md. Anwarul Abedin Department of Soil Science, Faculty of Agriculture, Bangladesh Agricultural University M. Moynul Haque Department of Agronomy, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University Manzer H. Siddiqui Department of Botany and Microbiology, College of Science, King Saud University Yoshiyuki Murata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Md. Anamul Hoque Department of Soil Science, Faculty of Agriculture, Bangladesh Agricultural University Salicylic acid (SA) and proline exhibit protective effects against a wide range of stresses. However, the combined impact of SA and proline on rice under drought stress is still unknown. Therefore, we investigated the protective roles of SA and/or proline in conferring drought tolerance in rice. There were eight treatments comprising the control (T1; 95-100% FC), 1.5 mM SA (T2), 2 mM proline (T3), 0.75 mM SA + 1 mM proline (T4), 45-50% FC (T5, drought stress), T5 + 1.5 mM SA (T6), T5 + 2 mM proline (T7), and T5 + 0.75 mM SA + 1 mM proline (T8), and two rice varieties: BRRI dhan66 and BRRI dhan75. Drought stress significantly decreased the plant growth, biomass, yield attributes, photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (Tr), photosynthetic pigments (chlorophyll and carotenoids content), relative water content (RWC), membrane stability index (MSI), soluble sugar and starch content, and uptake of N, P and K+ in roots and shoots. Drought-induced oxidative stress in the form of increased hydrogen peroxide (H2O2) production and lipid peroxidation (MDA) was observed. The combined application of SA (0.75 mM) + proline (1 mM) was found to be more effective than the single application of either for drought stress mitigation in rice. A combined dose of SA + proline alleviated oxidative stress through boosting antioxidant enzymatic activity in contrast to their separate application. The application of SA + proline also enhanced proline, soluble sugar and starch content, which resulted in the amelioration of osmotic stress. Consequently, the combined application of SA and proline significantly increased the gas exchange characteristics, photosynthetic pigments, RWC, MSI, nutrient uptake, plant growth, biomass and yield of rice. Therefore, the combined application of SA and proline alleviated the detrimental impacts of drought stress more pronouncedly than their separate application did by increasing osmoprotectants, improving nutrient transport, up-regulating antioxidant enzyme activity and inhibiting oxidative stress. No potential conflict of interest relevant to this article was reported.

Taylor and Francis Group Acta Medica Okayama 0951-8398 37 6 2023 Anti-oppressive global citizenship education in English language teaching: a three-pillar approach 1772 1787 EN Shawna M. Carroll Graduate School of Education, Okayama University Anti-oppressive global citizenship education (GCE), a specific strand of critical GCE, is a new field, especially concerning empirical studies within English classrooms. Based on an anti-oppressive GCE framework and the research question, “what does anti-oppressive theory look like in practice in English classrooms and how can this be woven into GCE?”, this paper explains the results of a project which used a portraiture methodology to collect and analyze approximately 6 hours of semi-structured interviews, detailed impressionistic records, and several lessons collected with one secondary school English teacher in Ontario, Canada. The portrait showcases how the educator implements a three-pillar approach to anti-oppressive GCE language education and the need to shine light on minoritized identities, create healthy soil for the foundation of learning about systemic oppression, and give the proper amounts of water/support to each student. No potential conflict of interest relevant to this article was reported.

Frontiers Media Acta Medica Okayama 2624-9553 4 2022 Sea Surface Temperature and Salinity in Lombok Strait Reconstructed From Coral Sr/Ca and δ18O, 1962–2012 918273 EN Ai Genda Graduate School of Natural Science and Technology, Okayama University Minoru Ikehara Center for Advanced Marine Core Research, Kochi University Atsushi Suzuki Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST) Ali Arman Research and Technology Center for Application of Isotope and Radiation, National Research and Innovation Agency Mayuri Inoue Graduate School of Natural Science and Technology, Okayama University Coral geochemical tracers have been used in studies of the paleoclimatology and paleoceanography of the tropics and subtropics. We measured Sr/Ca and oxygen isotope ratios (δ18O) in a coral sample collected from the southern part of Lombok Strait, a significant outlet of the Indonesian Throughflow (ITF) to the Indian Ocean, to reconstruct the historical record of sea surface temperature (SST) and seawater δ18O. Seawater δ18O can be used to approximate sea surface salinity (SSS) because it reflects the balance of evaporation and precipitation. The resulting time series reconstructed SST and SSS, covering the period 1962–2012, shows no clear trend of global warming, although the record includes a large cooling event (~4°C) during 1996–1997. Although neither SST nor SSS shows a systematic relationship with El Niño–Southern Oscillation and Indian Ocean Dipole (IOD), weak but significant correlations are found partly. In addition, the coral data show signals of major IOD and El Niño events in 1994 and 1997, respectively, although climatic trends recorded in the coral are not consistent with those found along the Java-Sumatra coast. To evaluate other influences on the ITF in Lombok Strait, we compared our coral record with coral records from sites in the Java Sea, the southern part of Makassar Strait, and Ombai Strait. During the northwest monsoon (December–January–February), variations in SST and SSS at Lombok Strait site are similar to those at the Java Sea and southern Makassar sites for the period 1962–1995, which suggests that low-salinity water from the Java Sea is carried at least to the southern part of Makassar Strait where it suppresses the ITF upstream from Lombok Strait. However, the SST and SSS records differ at the three sites during the southeast monsoon (June–July–August), indicating that surface conditions in Lombok Strait vary separately from those in the Java Sea. In the longer term, although global warming has been widely identified in the Indonesian Seas, the coral record shows no clear warming trend in the southern part of Lombok Strait, where fluctuations in the ITF may be modulating the distribution of heat in the surface waters of the western Pacific and eastern Indian Ocean. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-3417 13 12 2023 Hydrothermal Preparation of Faceted Vesicles Made of Span 40 and Tween 40 and Their Characterization 6893 EN Toshinori Shimanouchi Department of Environmental Chemistry and Materials, Okayama University Yui Komori Department of Environmental Chemistry and Materials, Okayama University Kazuki Toramoto Department of Environmental Chemistry and Materials, Okayama University Keita Hayashi National Institute of Technology, Nara College Kazuma Yasuhara Division of Materials Science, Nara Institute of Science and Technology (NAIST) Ho-Sup Jung Center for Food and Bioconvergence, Department of Food Science and Biotechnology, Seoul National University Yukitaka Kimura Department of Environmental Chemistry and Materials, Okayama University The Span 40 (sorbitan monooleate)/Tween 40 (polyoxyethylene sorbitan monolaurate) system gives faceted vesicles with angular surfaces, rather than spherical vesicles. Herein, a continuous and facile preparation method, based on the subcritical water-assisted emulsification and solvent diffusion, was presented to yield faceted vesicles with two major and minor axes (Type A) and vesicles closer to a polyhedron (Type B). Type A, rather than Type B, vesicles were likely to be formed. From the measurements concerning & zeta;-potential, membrane fluidity, and the polarization environment of the membranes, faceted vesicles could be obtained at 0.25 wt% of the surfactant concentration. The phase-separated behavior of Span 40 and Tween 40 within vesicle membranes could explain the structural feature of faceted vesicles and calcein leakage behavior. The significant advantage is that Type A vesicles would be utilized as alternative drug carriers for others with low encapsulation efficiency, although the present technical limitations cause difficulty in the selective formation of Type A and B vesicles and the selection of adequate solvent to accelerate the solvent diffusion step. No potential conflict of interest relevant to this article was reported.

Proceedings of the National Academy of Sciences Acta Medica Okayama 0027-8424 119 43 2022 Structures and mechanisms of actin ATP hydrolysis e2122641119 EN Yusuke Kanematsu Graduate School of Information Sciences, Hiroshima City University Akihiro Narita Structural Biology Research Center, Graduate School of Science, Nagoya University Toshiro Oda Faculty of Health and Welfare, Tokai Gakuin University Ryotaro Koike Graduate School of Informatics, Nagoya University Motonori Ota Graduate School of Informatics, Nagoya University Yu Takano Graduate School of Information Sciences, Hiroshima City University Kei Moritsugu Graduate School of Medical Life Science, Yokohama City University Ikuko Fujiwara Graduate School of Science, Osaka City University Kotaro Tanaka Structural Biology Research Center, Graduate School of Science, Nagoya University Hideyuki Komatsu Department of Bioscience and Bioinformatics, Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology Takayuki Nagae Synchrotron Radiation Research Center, Nagoya University Nobuhisa Watanabe Synchrotron Radiation Research Center, Nagoya University Mitsusada Iwasa Graduate School of Informatics, Nagoya University Yuichiro Maéda Research Institute for Interdisciplinary Science, Okayama University Shuichi Takeda Research Institute for Interdisciplinary Science, Okayama University The major cytoskeleton protein actin undergoes cyclic transitions between the monomeric G-form and the filamentous F-form, which drive organelle transport and cell motility. This mechanical work is driven by the ATPase activity at the catalytic site in the F-form. For deeper understanding of the actin cellular functions, the reaction mechanism must be elucidated. Here, we show that a single actin molecule is trapped in the F-form by fragmin domain-1 binding and present their crystal structures in the ATP analog-, ADP-Pi-, and ADP-bound forms, at 1.15-Å resolutions. The G-to-F conformational transition shifts the side chains of Gln137 and His161, which relocate four water molecules including W1 (attacking water) and W2 (helping water) to facilitate the hydrolysis. By applying quantum mechanics/molecular mechanics calculations to the structures, we have revealed a consistent and comprehensive reaction path of ATP hydrolysis by the F-form actin. The reaction path consists of four steps: 1) W1 and W2 rotations; 2) PG–O3B bond cleavage; 3) four concomitant events: W1–PO3− formation, OH− and proton cleavage, nucleophilic attack by the OH− against PG, and the abstracted proton transfer; and 4) proton relocation that stabilizes the ADP-Pi–bound F-form actin. The mechanism explains the slow rate of ATP hydrolysis by actin and the irreversibility of the hydrolysis reaction. While the catalytic strategy of actin ATP hydrolysis is essentially the same as those of motor proteins like myosin, the process after the hydrolysis is distinct and discussed in terms of Pi release, F-form destabilization, and global conformational changes. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 77 3 2023 Usefulness of Simple Diffusion Kurtosis Imaging for Head and Neck Tumors: An Early Clinical Study 273 280 EN Yudai Shimizu Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiro Kuroda Radiological Technology, Graduate School of Health Sciences, Okayama University Yuki Nakamitsu Radiological Technology, Graduate School of Health Sciences, Okayama University Wlla E. Al-Hammad Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Suzuka Yoshida Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuka Fukumura Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshihide Nakamura Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhiro Kuroda Radiological Technology, Graduate School of Health Sciences, Okayama University Ryo Kamizaki Radiological Technology, Graduate School of Health Sciences, Okayama University Satoshi Imajoh Radiological Technology, Graduate School of Health Sciences, Okayama University Yoshinori Tanabe Radiological Technology, Graduate School of Health Sciences, Okayama University Kohei Sugimoto Graduate School of Interdisciplinary Sciences and Engineering in Health Systems, Okayama University Masataka Oita Graduate School of Interdisciplinary Sciences and Engineering in Health Systems, Okayama University Irfan Sugianto Department of Oral Radiology, Faculty of Dentistry, Hasanuddin University Babatunde O. Bamgbose Department of Oral Diagnostic Sciences, Faculty of Dentistry, Bayero University Yoshinobu Yanagi Department of Dental Informatics, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Junichi Asaumi Department of Oral and Maxillofacial Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Original Article 10.18926/AMO/65492 Diffusion kurtosis (DK) imaging (DKI), a type of restricted diffusion-weighted imaging, has been reported to be useful for tumor diagnoses in clinical studies. We developed a software program to simultaneously create DK images with apparent diffusion coefficient (ADC) maps and conducted an initial clinical study. Multi-shot echo-planar diffusion-weighted images were obtained at b-values of 0, 400, and 800 sec/mm2 for simple DKI, and DK images were created simultaneously with the ADC map. The usefulness of the DK image and ADC map was evaluated using a pixel analysis of all pixels and a median analysis of the pixels of each case. Tumor and normal tissues differed significantly in both pixel and median analyses. In the pixel analysis, the area under the curve was 0.64 for the mean kurtosis (MK) value and 0.77 for the ADC value. In the median analysis, the MK value was 0.74, and the ADC value was 0.75. The MK and ADC values correlated moderately in the pixel analysis and strongly in the median analysis. Our simple DKI system created DK images simultaneously with ADC maps, and the obtained MK and ADC values were useful for differentiating head and neck tumors from normal tissue. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 77 3 2023 Early Fluid Balance Is Associated with 90-Day Mortality in Patients Receiving Continuous Renal Replacement Therapy 263 272 EN Yusheng Guo Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Junko Kosaka Department of Anesthesiology and Resuscitology, Okayama University Hospital Hiroshi Morimatsu Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/65491 Continuous renal replacement therapy (CRRT) is widely used to control fluid balance, but the optimal fluid balance to improve the prognosis of patients remains debated. Appropriate fluid management may depend on hemodynamic status. We investigated the association between 90-day mortality and fluid balance/mean arterial pressure (MAP) in patients receiving CRRT. This single-center retrospective study was conducted between May 2018 and March 2021. Based on the cumulative fluid balance at 72 h after initiation of CRRT, the cases were divided into negative (< 0 mL) and positive (> 0 mL) fluid balance groups. Ninety-day mortality was higher in the positive fluid balance group (p=0.009). At 4 h before and after CRRT initiation, the mean MAP was lower in the positive fluid balance group (p<0.05). After multivariate cox adjustment, 72-h positive fluid balance was independently associated with 90-day mortality (p=0.004). In addition, the cumulative fluid balance was associated with 90-day mortality (p<0.05) in cases without shock, high APACHE II score, sepsis, dialysis dependence, or vasopressor use. A 72-h positive fluid balance was associated with 90-day mortality in patients receiving CRRT. No potential conflict of interest relevant to this article was reported.

岡山大学理学部地球科学科 Acta Medica Okayama 1340-7414 29 1 2023 岡山県吉備中央町賀陽周辺の古第三系～新第三系の地質と吉備高原面のゆるやかな曲隆 1 27 EN Hajime TANAKA Seibu Engineering Consultants Co., Ltd. Shigeyuki SUZUKI Department of Earth Sciences, Okayama University 10.18926/ESR/65479 The Paleogene to Neogene successions which are composed of the Paleogene Kayo Formation, the late Oligocene to earliest Miocene Yagane Formation and the middle Miocene Ukan Formation are sporadically distributed in the Kibi Plateau region, surrounding area of Kibichuou Town, Okayama Prefecture, Southwest Japan. The gravel of the Kayo Formation occupied paleo-valley of Pre-Paleogene basement. The Yagane and Ukan formations unconformably overlay Pre-Paleogene rocks and occupy the gentle valley on the Kibi Surface as valley fill deposits.<br> The fluvial of the Kayo Formation is mainly composed of conglomerate with minor amount of sandstone and mudstone. The fluvial Yagane Formation is mainly composed of conglomerate and associated with sandstone, mudstone and coal beds. The marine Ukan Formation is subdivided into 3 members, the Yamagata Muddy sandstone Member (YMM), the Shimoyokomi Sandstone Member (SSM) and the Tsuneyama Mudstone Member (TMM) in ascending order. The YMM is characterized by the bio-disturbed very poorly sorted muddy sandstone with frequent burrows, which indicate tidal flat deposits. The SSM is mainly composed of parallel bedded well-sorted sandstone with occasional burrows, which suggest near shore deposits. The TMM is composed of homogeneous clay rich mudstone, which implies off shore deposits.<br> The boundary between the SSM and TMM (the contact of the sandstone and mudstone) is distinctive and correlative throughout the study area. The boundary is considered to be formed under similar water depth. The variations of the boundary height indicate a later ground movement. From the north to the south in about 25km distance, the height of the boundary changes 260m (in Ukan), 300m (in Takeshou), 360m (in Kibikogentoshi) and 260m (in Nichiouji). It indicates that a very gentle upwarping of the Kibi Plateau Surface was formed after the deposition of the Miocene. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2023 Photochemical properties of carbon nanotube/dendrimer hybrids for photocatalytic H2 evolution from water and biomedical imaging EN Masahiro YAMAGAMI Graduate School of Environmental and Life Science, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2023 Luminal Administration of a Water-soluble Carbon Monoxide–releasing Molecule (CORM-3) Mitigates Ischemia/Reperfusion Injury in Rats Following Intestinal Transplantation EN Takafumi OBARA Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University No potential conflict of interest relevant to this article was reported.

Frontiers Media Acta Medica Okayama 2296-634X 11 2023 Mutagenic analysis of actin reveals the mechanism of His161 flipping that triggers ATP hydrolysis 1105460 EN Mitsusada Iwasa Graduate School of Informatics, Nagoya University Shuichi Takeda Research Institute for Interdisciplinary Science (RIIS), Okayama University Akihiro Narita Structural Biology Research Center, Graduate School of Science, Nagoya University Yuichiro Maeda Research Institute for Interdisciplinary Science (RIIS), Okayama University Toshiro Oda Faculty of Health and Welfare, Tokai Gakuin University The dynamic assembly of actin is controlled by the hydrolysis of ATP, bound to the center of the molecule. Upon polymerization, actin undergoes a conformational change from the monomeric G-form to the fibrous F-form, which is associated with the flipping of the side chain of His161 toward ATP. His161 flipping from the gauche-minus to gauche-plus conformation leads to a rearrangement of the active site water molecules, including ATP attacking water (W1), into an orientation capable of hydrolysis. We previously showed that by using a human cardiac muscle a-actin expression system, mutations in the Pro-rich loop residues (A108G and P109A) and in a residue that was hydrogen-bonded to W1 (Q137A) affect the rate of polymerization and ATP hydrolysis. Here, we report the crystal structures of the three mutant actins bound to AMPPNP or ADP-P-i determined at a resolution of 1.35-1.55( )angstrom, which are stabilized in the F-form conformation with the aid of the fragmin F1 domain. In A108G, His161 remained non-flipped despite the global actin conformation adopting the F-form, demonstrating that the side chain of His161 is flipped to avoid a steric clash with the methyl group of A108. Because of the non-flipped His161, W1 was located away from ATP, similar to G-actin, which was accompanied by incomplete hydrolysis. In P109A, the absence of the bulky proline ring allowed His161 to be positioned near the Pro-rich loop, with a minor influence on ATPase activity. In Q137A, two water molecules replaced the side-chain oxygen and nitrogen of Gln137 almost exactly at their positions; consequently, the active site structure, including the W1 position, is essentially conserved. This seemingly contradictory observation to the reported low ATPase activity of the Q137A filament could be attributed to a high fluctuation of the active site water. Together, our results suggest that the elaborate structural design of the active site residues ensures the precise control of the ATPase activity of actin. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0032-3896 2023 Preparation of crystalline polyimide nanofibers via solution crystallization EN Shota Kumano Graduate School of Natural Science and Technology, Okayama University Tomoyasu Takaki Graduate School of Natural Science and Technology, Okayama University Tetsuya Uchida Graduate School of Natural Science and Technology, Okayama University Two crystalline polyimide nanofibers (PINFs) with different morphologies were prepared. The crystalline unit cells of the aromatic PI crystals and the crystal morphologies of the fabricated PINFs were examined. PINF-I (lengths = 305 ± 152 nm and diameters = 12 ± 2 nm) was crystallized from crystalline PI dissolved in a concentrated sulfuric acid solution. The resulting PINF-I was isolated from this solution, and it did not aggregate in water. PINF-II with diameters of 105 ± 99 nm was prepared by dispersing PINF-I in a mixed water and t-butanol (TBA) solution (water:TBA = 4:1), followed by freeze-drying. Then, the PINF-II was heated to enhance its crystallinity. X-ray diffraction and transmission electron microscopy studies of the heat-treated PINF-II revealed a PI crystalline unit cell [orthorhombic, a = 1.21 nm, b = 0.88 nm, and c = 2.23 nm (molecular chain axis direction)]. The crystal structure of the heat-treated PINF-II suggested that highly crystalline PINFs were fabricated in which the PI molecular chains were oriented along the direction of the fiber lengths. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2304-8158 12 6 2023 Taste Responses and Ingestive Behaviors to Ingredients of Fermented Milk in Mice 1150 EN Yuko Yamase Department of Dental Anesthesiology and Special Care Dentistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hai Huang Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yoshihiro Mitoh Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masahiko Egusa Department of Dental Anesthesiology and Special Care Dentistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takuya Miyawaki Department of Dental Anesthesiology and Special Care Dentistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ryusuke Yoshida Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Fermented milk is consumed worldwide because of its nutritious and healthful qualities. Although it is somewhat sour, causing some to dislike it, few studies have examined taste aspects of its ingredients. Wild-type mice and T1R3-GFP-KO mice lacking sweet/umami receptors were tested with various taste components (sucrose, galactose, lactose, galacto-oligosaccharides, fructo-oligosaccharides, l- and d-lactic acid) using 48 h two-bottle tests and short-term lick tests. d-lactic acid levels were measured after the ingestion of d- or; l-lactic acid or water to evaluate d-lactic acidosis. In wild-type mice, for the sweet ingredients the number of licks increased in a concentration-dependent manner, but avoidance was observed at higher concentrations in 48 h two-bottle tests; the sour ingredients d- and l-lactic acid showed concentration-dependent decreases in preference in both short- and long-term tests. In 48 h two-bottle tests comparing d- and l-lactic acid, wild-type but not T1R3-GFP-KO mice showed higher drinking rates for l-lactic acid. d-lactic acidosis did not occur and thus did not contribute to this preference. These results suggest that intake in short-term lick tests varied by preference for each ingredient, whereas intake variation in long-term lick tests reflects postingestive effects. l-lactic acid may have some palatable taste in addition to sour taste. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2073-4360 15 5 2023 Shear Bond Strength of Resin Luting Materials to Lithium Disilicate Ceramic: Correlation between Flexural Strength and Modulus of Elasticity 1128 EN Masao Irie Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Masahiro Okada Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Yukinori Maruo Department of Prosthodontics, Division of Dentistry, Okayama University Goro Nishigawa Department of Prosthodontics, Division of Dentistry, Okayama University Takuya Matsumoto Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science This study investigates the effect of the curing mode (dual-cure vs. self-cure) of resin cements (four self-adhesive and seven conventional cements) on their flexural strength and flexural modulus of elasticity, alongside their shear bond strength to lithium disilicate ceramics (LDS). The study aims to determine the relationship between the bond strength and LDS, and the flexural strength and flexural modulus of elasticity of resin cements. Twelve conventional or adhesive and self-adhesive resin cements were tested. The manufacturer's recommended pretreating agents were used where indicated. The shear bond strengths to LDS and the flexural strength and flexural modulus of elasticity of the cement were measured immediately after setting, after one day of storage in distilled water at 37 degrees C, and after 20,000 thermocycles (TC 20k). The relationship between the bond strength to LDS, flexural strength, and flexural modulus of elasticity of resin cements was investigated using a multiple linear regression analysis. For all resin cements, the shear bond strength, flexural strength, and flexural modulus of elasticity were lowest immediately after setting. A clear and significant difference between dual-curing and self-curing modes was observed in all resin cements immediately after setting, except for ResiCem EX. Regardless of the difference of the core-mode condition of all resin cements, flexural strengths were correlated with the LDS surface upon shear bond strengths (R-2 = 0.24, n = 69, p < 0.001) and the flexural modulus of elasticity was correlated with them (R-2 = 0.14, n = 69, p < 0.001). Multiple linear regression analyses revealed that the shear bond strength was 17.877 + 0.166, the flexural strength was 0.643, and the flexural modulus was (R-2 = 0.51, n = 69, p < 0.001). The flexural strength or flexural modulus of elasticity may be used to predict the bond strength of resin cements to LDS. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2023 1 2023 Detection of the 4.4-MeV gamma rays from 16O(ν, ν′)16O(12.97 MeV, 2−) with a water Cherenkov detector in supernova neutrino bursts 013D02 EN Makoto Sakuda Physics Department, Okayama University Toshio Suzuki Department of Physics, College of Humanities and Sciences, Nihon University Mandeep Singh Reen Department of Physics, Akal University Ken'Ichiro Nakazato Faculty of Arts and Science, Kyushu University Hideyuki Suzuki Department of Physics, Faculty of Science and Technology, Tokyo University of Science We first discuss and determine the isospin mixing of the two 2− states (12.53 MeV and 12.97 MeV) of the16O nucleus using inelastic electron scattering data. We then evaluate the cross section of 4.4-MeV γ rays produced in the neutrino neutral-current (NC) reaction 16O(ν, ν′)16O(12.97 MeV, 2−) in a water Cherenkov detector at a low energy, below 100 MeV. The detection of γ rays for Eγ > 5 MeV from the NC reaction 16O(ν, ν′)16O(Ex > 16 MeV, T = 1) with a water Cherenkov detector in supernova neutrino bursts has been proposed and discussed by several authors previously. In this article, we discuss a new NC reaction channel from 16O(12.97 MeV, 2−) producing a 4.4-MeV γ ray, the cross section of which is more robust and even larger at low energy (Eν < 25 MeV) than the NC cross section from 16O(Ex > 16 MeV, T = 1). We also evaluate the number of such events induced by neutrinos from supernova explosion which can be observed by the Super-Kamiokande, an Earth-based 32-kton water Cherenkov detector. No potential conflict of interest relevant to this article was reported.

岡山大学経済学会 Acta Medica Okayama 2433-4146 54 3 2023 日中韓の地域間国際間の水誘発構造　―日中韓地域間国際産業連関表による分析― 17 35 EN Taku Ishiro 10.18926/OER/65010 　When we analyze the international and interregional relation we need the Transnational Interregional Input-Output Table based on International Input-Output Table. At the moment Transnational Interregional Input-Output Table between Japan and China （TIIOT） made by IDE-JETRO provide the most useful information about these research. However, the regional classification of Japan in the table is not classified in detail such as Hokkaido, Tohoku, Kanto and so on. Therefore, the author divide Kanto area of TIIOT into 11 regions by information based on author's study （Ishiro （2011））. Furthermore, we divide the South Korea into 6 regions to expand our study and database. We analyze water footprint between Japan and mainland China and South Korea （Ishiro and Hasebe （2013））. Additionally, we expand our database to divide 7 region of mainland China into 30 regions by information of China multi-regional input-output table（ Ishiro and Yu（2016））. In this study we analyze the water inducement structures between Japan's Tokyo and Kanagawa and China's Beijing and Shanghai and South Koreaʼs Sudogwon by the database of Ishiro and Yu（2016） No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 0304-3800 464 2022 Quantifying the GCM-related uncertainty for climate change impact assessment of rainfed rice production in Cambodia by a combined hydrologic - rice growth model 109815 EN K. Tsujimoto Graduate School of Environmental and Life Science, Okayama University N. Kuriya Faculty of Environmental Science and Technology, Okayama University T. Ohta Assistance Unit for Research and Engineering Development (U-PRIMO) K. Homma Graduate School of Agricultural Science, Tohoku University M.So Im Ministry of Water Resources and Meteorology (MOWRAM) of Cambodia The effects of climate change on agriculture are a major concern for global food security. In this study, the impacts of climate change on rainfed rice production in the granary of Cambodia were examined on a basin scale by developing and applying a combined model consisting of a crop model and a basin-scale distributed hydrological model. The response of rice production to soil-water availability was simulated for past (1981–2000) and future (2041–2060, 2081–2100) periods. From 34 general circulation models (GCMs) that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5), 5 GCMs were selected by evaluating monthly rainfall in the past. Although annual rainfall was projected to increase by all five selected GCMs, notable decreases in rainfed rice production were projected with 3 GCMs, while small changes were projected with the other 2 GCMs. The main factor restricting future rice production was soil water availability, brought by the projected change in the seasonal distribution of rainfall and the projected more severe dry spells in the early monsoon season. The results suggest the importance of the selection and bias correction of GCMs to force rice crop models and of the simulation of soil water flow on a basin scale for the assessment of rain-fed rice production. In particular, improvements in projections of rainfall amounts over shorter periods rather than annual or seasonal periods, which fit within the time scales of rice plant growth, were suggested to be important. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1999-4923 15 1 2022 Formation of a Stable Co-Amorphous System for a Brick Dust Molecule by Utilizing Sodium Taurocholate with High Glass Transition Temperature 84 EN Shohei Aikawa Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Okayama University Hironori Tanaka Formulation Research Department, Formulation R&D Laboratory, Shionogi & Co., Ltd. Hiroshi Ueda Bioanalytical, Analysis and Evaluation Laboratory, Shionogi & Co., Ltd. Masato Maruyama Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Okayama University Kazutaka Higaki Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Okayama University Brick dust molecules are usually poorly soluble in water and lipoidal components, making it difficult to formulate them in dosage forms that provide efficient pharmacological effects. A co-amorphous system is an effective strategy to resolve these issues. However, their glass transition temperatures (Tg) are relatively lower than those of polymeric amorphous solid dispersions, suggesting the instability of the co-amorphous system. This study aimed to formulate a stable co-amorphous system for brick dust molecules by utilizing sodium taurocholate (NaTC) with a higher Tg. A novel neuropeptide Y-5 receptor antagonist (AntiY(5)R) and NaTC with Tg of 155 degrees C were used as the brick dust model and coformer, respectively. Ball milling formed a co-amorphous system for AntiY(5)R and NaTC (AntiY(5)R-NaTC) at various molar ratios. Deviation from the theoretical Tg value and peak shifts in Fourier-transform infrared spectroscopy indicated intermolecular interactions between AntiY(5)R and NaTC. AntiY(5)R-NaTC at equal molar ratios resulting in an 8.5-fold increase in AntiY(5)R solubility over its crystalline form. The co-amorphous system remained amorphous for 1 month at 25 degrees C and 40 degrees C. These results suggest that the co-amorphous system formed by utilizing NaTC as a coformer could stably maintain the amorphous state and enhance the solubility of brick dust molecules. No potential conflict of interest relevant to this article was reported.

American Geophysical Union Acta Medica Okayama 1942-2466 14 12 2022 Too Frequent and Too Light Arctic Snowfall With Incorrect Precipitation Phase Partitioning in the MIROC6 GCM e2022MS003046 EN Yuki Imura Department of Earth Sciences, Okayama University Takuro Michibata Department of Earth Sciences, Okayama University Cloud-phase partitioning has been studied in the context of cloud feedback and climate sensitivity; however, precipitation-phase partitioning also has a significant role in controlling the energy budget and sea ice extent. Although some global models have introduced a more sophisticated precipitation parameterization to reproduce realistic cloud and precipitation processes, the effects on the process representation of mixed- and ice-phase precipitation are poorly understood. Here, we evaluate how different precipitation modeling (i.e., diagnostic [DIAG] vs. prognostic [PROG] schemes) affects the simulated precipitation phase and occurrence frequency. Two versions of MIROC6 were used with the satellite simulator COSP2. Although the PROG scheme significantly improves the simulated cloud amount and snowfall rates, the phase partitioning, frequency, and intensity of precipitation with the PROG scheme are still biased, and are even worse than with the DIAG scheme. We found a "too frequent and too light" Arctic snowfall bias in the PROG, which cannot be eliminated by model tuning. The cloud-phase partitioning is also affected by the different approaches used to consider precipitation. The ratio of supercooled liquid water is underrepresented by switching from the DIAG to PROG scheme, because some snowflakes are regarded to be cloud ice. Given that the PROG precipitation retains more snow in the atmosphere, the underestimation becomes apparent when other models incorporate the PROG scheme. This depends on how much precipitation is within the clouds in the model. Our findings emphasize the importance of correctly reproducing the phase partitioning of cloud and precipitation, which ultimately affects the simulated climate sensitivity. Plain Language Summary This study examined cloud and precipitation phase partitioning (i.e., the ratio between liquid and ice) in the Arctic using the MIROC6 global climate model (GCM). Despite recent advances in precipitation modeling by GCMs, the associations between the macrostructures (i.e., cloud coverage and precipitation rate) and phase partitioning have been little studied. Prognostic treatment of precipitation, which is a more sophisticated parameterization, yields seasonal and annual cloud cover and snowfall that are in better agreement with satellite observations. However, it tends to generate snowfall too frequently and too lightly, resulting in the misrepresentation of precipitation phase partitioning. In addition, there is a risk of overestimating the ratio of cloud ice to cloud liquid by including prognostic precipitation. The bias is difficult to remove by model tuning alone. If the models misrepresent the precipitation phase partitioning, then the bias will further influence feedback processes in a future warming scenario through the snow-to-rain phase change, similar to the cloud phase feedback. Our findings emphasize the importance of conducting process-oriented model evaluations on a regional scale. No potential conflict of interest relevant to this article was reported.

Public Library Science Acta Medica Okayama 1932-6203 17 12 2022 Behavioural osmoregulation during land invasion in fish: Prandial drinking and wetting of the dry skin e0277968 EN Yukitoshi Katayama Ushimado Marine Institute, Faculty of Science, Okayama University Takehiro Tsukada Department of Biomolecular Science, Toho University Susumu Hyodo Laboratory of Physiology, Atmosphere and Ocean Research Institute, University of Tokyo Hirotaka Sakamoto Ushimado Marine Institute, Faculty of Science, Okayama University Tatsuya Sakamoto Ushimado Marine Institute, Faculty of Science, Okayama University Osmoregulatory behaviours should have evolutionarily modified for terrestrialisation of vertebrates. In mammals, sensations of buccal food and drying have immediate effects on postprandial thirst to prevent future systemic dehydration, and is thereby considered to be 'anticipatory thirst'. However, it remains unclear whether such an anticipatory response has been acquired in the non-tetrapod lineage. Using the mudskipper goby (Periophthalmus modestus) as a semi-terrestrial ray-finned fish, we herein investigated postprandial drinking and other unique features like full-body 'rolling' over on the back although these behaviours had not been considered to have osmoregulatory functions. In our observations on tidal flats, mudskippers migrated into water areas within a minute after terrestrial eating, and exhibited rolling behaviour with accompanying pectoral-fin movements. In aquarium experiments, frequency of migration into a water area for drinking increased within a few minutes after eating onset, without systemic dehydration. During their low humidity exposure, frequency of the rolling behaviour and pectoral-fin movements increased by more than five times to moisten the skin before systemic dehydration. These findings suggest anticipatory responses which arise from oral/gastrointestinal and cutaneous sensation in the goby. These sensation and motivation seem to have evolved in distantly related species in order to solve osmoregulatory challenges during terrestrialisation. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 2186-7755 112 2023 Effect of seed cold PEG–priming concentration and period followed by re–drying on germination, growth and flowering of Eustoma grandiflorum （Raf.） Shinn ʻExe Lavenderʼ 7 12 EN Thao Thu Phan Graduate School of Environmental and Life Science, Okayama University Keigo Fukushima Hiroshima Prefectural Technology Research Institute, Agricultural Technology Research Center Yoshiyuki Tanaka Graduate School of Environmental and Life Science, Okayama University Ken-ichiro Yasuba Graduate School of Environmental and Life Science, Okayama University Yuichi Yoshida Graduate School of Environmental and Life Science, Okayama University Tanjuro Goto Graduate School of Environmental and Life Science, Okayama University This study aimed to investigate whether seed cold priming by PEG‒6000, followed by re‒drying would affect the germination, growth, and flowering of Eustoma ‘Exe Lavender’ raised seedling under high temperatures. Seeds of control treatment were not treated with cold‒priming or re‒drying. In experiment 1, seeds were cold‒primed with water and PEG‒6000 at ‒0.75 and ‒1.5 MPa for 5 weeks at 10°C in the dark and then subjected to re‒dried and storage for 30 days at 10°C. The results showed that cold‒primed seeds germinated earlier than those of the control. Compared to water treatment, plants grown from PEG‒6000 treatments and re‒drying showed similar germination rate, bolting rate, days to bolting, bolting node and flowering rate. In experiment 2, cold priming periods by water and ‒1.5 MPa PEG‒6000 were investigated for 4, 5, 6, 7, and 8 weeks. ‘Exe Lavender’ seeds treated with cold water and in the dark for longer than 5 weeks increased their percentage of radicle emergence and decreased germination rate after 30 days of re‒drying and storage. Meanwhile, those treated with cold-PEG did not protrude the radicle even for 8 weeks of priming and maintained the germination rate after re‒drying and storage. Days to bolting and days to flowering tended to decrease when the priming period decreased. The results suggest that the seed cold priming treatment by ‒1.5 MPa PEG‒6000 and subsequent re‒drying improved germination rate and maintained bolting rate and flowering rate in Eustoma compared to cold priming treatment by water raised seedling under high temperature conditions. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2071-1050 15 1 2022 Interspecific Variability in Growth Characteristics and Phytoremediation of Cu by Free-Floating Azolla Macrophytes 497 EN Muhammad Shahbaz Akhtar Department of Environmental Sciences, Forman Christian College University Sohaib Aslam Department of Environmental Sciences, Forman Christian College University Allah Ditta Department of Environmental Sciences, Shaheed Benazir Bhutto University Bedur Faleh A. Albalawi Department of Biology, University of Tabuk Yoko Oki Department of Environmental Management Engineering, Graduate School of Environmental and Life Science, Okayama University Yoshitaka Nakashima Department of Environmental Management Engineering, Graduate School of Environmental and Life Science, Okayama University The phytoremediation potential of aquatic plants, particularly for Cu, is scarcely reported in the pertinent literature. In this regard, differential growth behavior and phytoaccumulation ability of three free-floating Azolla species (A. japonica, A. pinnata, and A. hybrid) were evaluated in a climatically controlled (a temperature of 25/20 degrees C, light/dark 16/8 h, a light intensity of 60 mu mol m(-2) s(-1), and a relative humidity of 65%) microcosm study. Azolla plants were exposed to solutions having three Cu concentrations (0, 3, and 6 mg L-1) under two incubation periods (4 and 8 days). Different Cu treatments significantly reduced Azolla biomass during both incubation periods and A. pinnata was the most sensitive species. Azolla plants grown in aqueous solutions showed substantial variations in Cu removal capacity. Higher bioconcentration values displayed by Azolla plants indicated that these plants can be deployed as potential plants for Cu removal from Cu contaminated water. Nevertheless, the plants exposed to higher Cu concentrations displayed color changes and root detachment due to Cu phytotoxic effects which may also ultimately lead to plant death. Significant correlations between Cu removed from the aqueous solutions and Cu contents of plant biomass indicated that Cu phytoremediation by Azolla plants was due to the phytoaccumulation mechanism because the removed Cu from aqueous solutions was accumulated in plant biomass. Introduced Azolla species, i.e., A. hybrid, displayed comparable Cu removal efficiency with naturally grown Azolla species, i.e., A. japonica and A. pinnata. Tested Azolla species proved to be suitable candidates to remediate Cu contaminated water and can be deployed for phytoremediation. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 23 1 2022 Thickness Measurement at High Lift-Off for Underwater Corroded Iron-Steel Structures Using a Magnetic Sensor Probe 380 EN Shoya Adachi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Minoru Hayashi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Taisei Kawakami Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yuto Ando Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Jin Wang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kenji Sakai Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toshihiko Kiwa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toshiyuki Ishikawa Department of Civil, Environmental and Applied System Engineering, Faculty of Environmental and Urban Engineering, Kansai University Keiji Tsukada Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Infrastructure facilities that were built approximately half a century ago have rapidly aged. Steel sheet piles, the inspection object in this study, are severely corroded, resulting in cave-in damages at wharfs. To solve such a problem, non-destructive inspection techniques are required. We previously demonstrated plate thickness measurement using extremely low-frequency eddy current testing. However, when the steel sheet piles are located in water, shellfish adhere to their surface, causing a lift-off of several tens of millimeters. Therefore, this large lift-off hinders the thickness measurement owing to fluctuations of magnetic signals. In this study, sensor probes with different coil diameters were prototyped and the optimum size for measuring steel sheet piles at high lift-off was investigated. Using the probes, the magnetic field was applied with a lift-off range from 0 to 80 mm, and the intensity and phase of the detected magnetic field were analyzed. Subsequently, by increasing the probe diameter, a good sensitivity was obtained for the thickness estimation with a lift-off of up to 60 mm. Moreover, these probes were used to measure the thickness of actual steel sheet piles, and measurements were successfully obtained at a high lift-off. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 1083-351X 298 12 2022 Crystal structures of photosystem II from a cyanobacterium expressing psbA2 in comparison to psbA3 reveal differences in the D1 subunit 102668 EN Yoshiki Nakajima Research Institute for Interdisciplinary Science, Okayama University Natsumi Ugai-Amo Graduate School of Natural Science and Technology, Okayama University Naoki Tone Graduate School of Natural Science and Technology, Okayama University Akiko Nakagawa Proteo-Science Research Center, Ehime University Masako Iwai Graduate School and College of Arts and Sciences, The University of Tokyo Masahiko Ikeuchi Graduate School and College of Arts and Sciences, The University of Tokyo Miwa Sugiura Proteo-Science Research Center, Ehime University Michihiro Suga Research Institute for Interdisciplinary Science, Okayama University Shen Jian-Ren Research Institute for Interdisciplinary Science, Okayama University Three psbA genes (psbA1, psbA2, and psbA3) encoding the D1 subunit of photosystem II (PSII) are present in the ther-mophilic cyanobacterium Thermosynechococcus elongatus and are expressed differently in response to changes in the growth environment. To clarify the functional differences of the D1 protein expressed from these psbA genes, PSII dimers from two strains, each expressing only one psbA gene (psbA2 or psbA3), were crystallized, and we analyzed their structures at resolu-tions comparable to previously studied PsbA1-PSII. Our results showed that the hydrogen bond between pheophytin/D1 (PheoD1) and D1-130 became stronger in PsbA2-and PsbA3-PSII due to change of Gln to Glu, which partially explains the increase in the redox potential of PheoD1 observed in PsbA3. In PsbA2, one hydrogen bond was lost in PheoD1 due to the change of D1-Y147F, which may explain the decrease in stability of PheoD1 in PsbA2. Two water molecules in the Cl-1 channel were lost in PsbA2 due to the change of D1-P173M, leading to the narrowing of the channel, which may explain the lower efficiency of the S-state transition beyond S2 in PsbA2-PSII. In PsbA3-PSII, a hydrogen bond between D1-Ser270 and a sulfoquinovosyl-diacylglycerol molecule near QB dis-appeared due to the change of D1-Ser270 in PsbA1 and PsbA2 to D1-Ala270. This may result in an easier exchange of bound QB with free plastoquinone, hence an enhancement of oxygen evolution in PsbA3-PSII due to its high QB exchange efficiency. These results provide a structural basis for further functional examination of the three PsbA variants. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 23 23 2022 Alterations in UPR Signaling by Methylmercury Trigger Neuronal Cell Death in the Mouse Brain 15412 EN Ryosuke Nomura Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hideki Hiraoka Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuta Iijima Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takao Iwawaki Division of Cell Medicine, Department of Life Science, Medical Research Institute, Kanazawa Medical University Yoshito Kumagai Environmental Biology Laboratory, Faculty of Medicine, University of Tsukuba Masatake Fujimura Department of Basic Medical Science, National Institute for Minamata Disease Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Methylmercury (MeHg), an environmental toxicant, induces neuronal cell death and injures specific areas of the brain. MeHg is known to induce oxidative and endoplasmic reticulum (ER) stress. The unfolded protein response (UPR) pathway has a dual nature in that it regulates and protects cells from an overload of improperly folded proteins in the ER, whereas excessively stressed cells are eliminated by apoptosis. Oxidative stress/ER stress induced by methylmercury exposure may tilt the UPR toward apoptosis, but there is little in vivo evidence of a direct link to actual neuronal cell death. Here, by using the ER stress-activated indicator (ERAI) system, we investigated the time course signaling alterations of UPR in vivo in the most affected areas, the somatosensory cortex and striatum. In the ERAI-Venus transgenic mice exposed to MeHg (30 or 50 ppm in drinking water), the ERAI signal, which indicates the activation of the cytoprotective pathway of the UPR, was only transiently enhanced, whereas the apoptotic pathway of the UPR was persistently enhanced. Furthermore, detailed analysis following the time course showed that MeHg-induced apoptosis is strongly associated with alterations in UPR signaling. Our results suggest that UPR modulation could be a therapeutic target for treating neuropathy. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1880-7062 44 1 2022 Chemopreventive effects and anti-tumorigenic mechanisms of Actinidia arguta, known as sarunashi in Japan toward 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)- induced lung tumorigenesis in a/J mouse 26 EN Jun Takata Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Naoko Miyake Faculty of Pharmaceutical Sciences, Okayama University Yusuke Saiki Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Misako Tada Faculty of Pharmaceutical Sciences, Okayama University Kensuke Sasaki Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshio Kubo Department of Allergy and Respiratory Medicine, Okayama University Hospital Katsuyuki Kiura Department of Allergy and Respiratory Medicine, Okayama University Hospital Sakae Arimoto-Kobayashi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background<br> Previously, we reported the inhibitory effect of Actinidia arguta juice, known as sarunashi juice (sar-j) in Japan, on mutagenesis, inflammation, and mouse skin tumorigenesis. The components of A. arguta responsible for the anti-mutagenic effects were identified to be water-soluble, heat-labile phenolic compounds. We proposed isoquercetin (isoQ) as a candidate anticarcinogenic component. In this study, we sought to investigate the chemopreventive effects of A. arguta juice and isoQ on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in A/J mice, and identify the possible mechanisms underlying the anti-tumorigenic effects of A. arguta.<br> <br> Results<br> The number of tumor nodules per mouse lung in the group injected with NNK and administered A. arguta juice orally was significantly lower than that in the group injected with NNK only. Oral administration of isoQ also reduced the number of nodules in the mouse lungs. As expected, the mutagenicity of NNK and 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) detected using S. typhimurium TA1535 decreased in the presence of sar-j. However, NNK and MNNG mutagenicity detected using S. typhimurium YG7108, a strain lacking the O6-methylguanine DNA methyltransferases (ogtST and adaST) did not decrease in the presence of sar-j suggesting that sar-j may mediate its antimutagenic effect by enhancing the DNA damage repair by ogtST and adaST. Phosphorylation of Akt, with or without epidermal growth factor stimulation, in A549 cells was significantly decreased following sar-j and isoQ treatment, indicating that components in sar-j including isoQ suppressed the PI3K/AKT signaling pathways.<br> <br> Conclusions<br> Sar-j and isoQ reduced NNK-induced lung tumorigenesis. Sar-j targets both the initiation and growth/progression steps during carcinogenesis, specifically via anti-mutagenesis, stimulation of alkyl DNA adduct repair, and suppression of Akt-mediated growth signaling. IsoQ might contribute in part to the biological effects of sar-j via suppression of Akt phosphorylation, but it may not be the main active ingredient. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0010-8545 471 2022 Geometric, electronic and spin structures of the CaMn4O5 catalyst for water oxidation in oxygen-evolving photosystem II. Interplay between experiments and theoretical computations 214742 EN Kizashi Yamaguchi Center for Quantum Information and Quantum Biology, Osaka University Mitsuo Shoji Center of Computational Sciences, Tsukuba University Hiroshi Isobe Research Institute for Interdisciplinary Science, and Graduate School of Natural Science and Technology, Okayama University Takashi Kawakami RIKEN Center for Computational Science Koichi Miyagawa Center of Computational Sciences, Tsukuba University Michihiro Suga Research Institute for Interdisciplinary Science, and Graduate School of Natural Science and Technology, Okayama University Fusamichi Akita Research Institute for Interdisciplinary Science, and Graduate School of Natural Science and Technology, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, and Graduate School of Natural Science and Technology, Okayama University The aim of this review is to elucidate geometric structures of the catalytic CaMn4Ox (x = 5, 6) cluster in the Kok cycle for water oxidation in the oxygen evolving complex (OEC) of photosystem II (PSII) based on the high-resolution (HR) X-ray diffraction (XRD) and serial femtosecond crystallography (SFX) experiments using the X-ray free-electron laser (XFEL). Quantum mechanics (QM) and QM/molecular mechanics (MM) computations are performed to elucidate the electronic and spin structures of the CaMn4Ox (x = 5, 6) cluster in five states S-i (i = 0 similar to 4) on the basis of the X-ray spectroscopy, electron paramagnetic resonance (EPR) and related experiments. Interplay between the experiments and theoretical computations has been effective to elucidate the coordination structures of the CaMn4Ox (x = 5, 6) cluster ligated by amino acid residues of the protein matrix of PSII, valence states of the four Mn ions and total spin states by their exchange-couplings, and proton-shifted isomers of the CaMn4Ox (x = 5, 6) cluster. The HR XRD and SFX XFEL experiments have also elucidated the biomolecular systems structure of OEC of PSII and the hydrogen bonding networks consisting of water molecules, chloride anions, etc., for water inlet and proton release pathways in PSII. Large-scale QM/MM computations have been performed for elucidation of the hydrogen bonding distances and angles by adding invisible hydrogen atoms to the HR XRD structure. Full geometry optimizations by the QM and QM/MM methods have been effective for elucidation of the molecular systems structure around the CaMn4Ox (x = 5, 6) cluster in OEC. DLPNO-CCSD(T-0) method has been applied to elucidate relative energies of possible intermediates in each state of the Kok cycle for water oxidation. Implications of these results are discussed in relation to the blueprint for developments of artificial catalysts for water oxidation. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1226-8615 25 4 2022 Longevity of Lucilia sericata (Meigen, 1826) used as pollinator 101999 EN Koichi Shimomae Graduate School of Environmental and Life Science, Okayama University Takuya Sato Japan Maggot Company, Co. Ltd. Yuichi Yoshida Graduate School of Environmental and Life Science, Okayama University Shine Shane Naing Graduate School of Environmental and Life Science, Okayama University Takahisa Miyatake Graduate School of Environmental and Life Science, Okayama University Pollinators play an important role in the production of many agricultural products. Honeybees, Apis mellifera L., are leading pollinators, but the number of honeybees in the world is declining. Finding alternatives is beginning to be important. In the present study, we compared the longevity of Lucilia sericata (Meigen, 1826), which is used as a pollinator, in cages in the laboratory and in a vinyl greenhouse under controlled feeding conditions. First, we showed that the longevity of the flies was significantly extended (c.a. 40 days) in the laboratory when water and sugar were supplied compared to the cases without sugar and/or water. Second, we found that the average longevity was 20 days with water and sugar in cages kept in a vinyl greenhouse during the summer. Finally, we released marked flies into a vinyl greenhouse where strawberries were cultivated without feeding water or sugar in the spring. As a result, fewer than 10% of the flies survived 10 days after release. Based on the result, we discuss the use of this species as a pollinator in the context of its survival rate. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1520-6106 126 38 2022 Roles of the Flexible Primary Coordination Sphere of the Mn4CaOx Cluster: What Are the Immediate Decay Products of the S-3 State? 7212 7228 EN Hiroshi Isobe Research Institute for Interdisciplinary Science, Okayama University Mitsuo Shoji Center for Computational Science, University of Tsukuba, Takayoshi Suzuki Research Institute for Interdisciplinary Science, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Okayama University Kizashi Yamaguchi Institute for NanoScience Design, Osaka University The primary coordination sphere of the multinuclear cofactor (Mn4CaOx) in the oxygen-evolving complex (OEC) of photosystem II is absolutely conserved to maintain its structure and function. Recent time-resolved serial femtosecond crystallography identified large reorganization of the primary coordination sphere in the S-2 to S-3 transition, which elicits a cascade of events involving Mn oxidation and water molecule binding to a putative catalytic Mn site. We examined how the crystallographic fields, created by transient conformational states of the OEC at various time points, affect the thermodynamics of various isomers of the Mn cluster using DFT calculations, with an aim of comprehending the functional roles of the flexible primary coordination sphere in the S-2 to S-3 transition and in the recovery of the S-2 state. The results show that the relative movements of surrounding residues change the size and shape of the cavity of the cluster and thereby affect the thermodynamics of various catalytic intermediates as well as the ability to capture a new water molecule at a coordinatively unsaturated site. The implication of these findings is that the protein dynamics may serve to gate the catalytic reaction efficiently by controlling the sequence of Mn oxidation/reduction and water binding/release. This interpretation is consistent with EPR experiments; g similar to 5 and g similar to 3 signals obtained after near-infrared (NIR) excitation of the S-3 state at 4 K and a g similar to 5 only signal produced after prolonged incubation of the S-3 state at 77 K can be best explained as originating from water-bound S-2 clusters (S-total = 7/2) under a S-3 ligand field, i.e., the immediate one-electron reduction products of the oxyl-oxo (S-total = 6) and hydroxo-oxo (S-total = 3) species in the S-3 state. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2022 The impacts of droughts, local land-use policies, and anthropogenic activities against water resources in the upstream Sesan river basin, Central Highlands of Vietnam EN VO NGOC QUYNH TRAM Graduate School of Environmental and Life Science, Okayama University No potential conflict of interest relevant to this article was reported.