Wiley Acta Medica Okayama 2688-4046 6 3 2026 PPy‐Coated Wire Actuators for the Micromechanostimulation of Cells: Fabrication and Characterization e202500639 EN Amaia B. Ortega‐Santos Sensor and Actuator Systems, Department of Physics Chemistry and Biology (IFM), Linköping University Satoru Hayano Department of Orthodontics, Okayama University Hospital Emilio Satoshi Hara Advanced Research Center for Oral and Craniofacial Sciences Dental School, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Jose G. Martínez Sensor and Actuator Systems, Department of Physics Chemistry and Biology (IFM), Linköping University Hiroshi Kamioka Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Edwin W. H. Jager Sensor and Actuator Systems, Department of Physics Chemistry and Biology (IFM), Linköping University Cellular mechanotransduction signals play a crucial role in physiological and pathological conditions, including skeletal disorders. Although various systems exist to mechanically stimulate cultured cells, most are constrained by incubator incompatibility, limited physiological relevance, nonuniform stimulation, or complexity. The objective of this article is to develop and validate a compact, incubator-compatible tool capable of delivering localized and physiologically relevant mechanical stimulation to small cell populations. Here, we introduce a polypyrrole-based wire-shaped microactuator designed to induce localized mechanical stress to adjacent cells. These wire-shaped microactuators are biocompatible, easy-to-use, and compact for use within standard in vitro cell culture systems. Using a noncontact optical method, we characterize the actuation of polypyrrole-coated wires in an aqueous NaDBS electrolyte, showing radial expansion of 1.5–8 µm depending on the deposited polypyrrole film thickness, comparable to cellular dimensions. Next, the actuation is confirmed to be robust and stable to use in cell culture media at physiological temperature. To evaluate biological relevance, osteoblastic KUSA-A1 cells are mechanically stimulated inside the incubator and transcriptomic changes are assessed. Mechanical stimulation resulted in upregulation of genes previously associated with mechanotransduction, including Fos and Fosb. Additionally, several uncharacterized long noncoding RNAs are differentially expressed, suggesting potential novel players in the mechanotransduction pathway. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1424-8220 25 21 2025 Integrated Authentication Server Design for Efficient Kerberos–Blockchain VANET Authentication 6651 EN Maya Rahayu Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Md. Biplob Hossain Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Samsul Huda Interdisciplinary Education and Research Field, Okayama University Yasuyuki Nogami Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Vehicular Ad Hoc Network (VANET) is a fundamental component of the intelligent transportation systems (ITS), providing critical road information to users. However, the volatility of VANETs creates significant vulnerabilities from malicious actors. Thus, verifying joining entities is crucial to maintaining the VANET’s communication security. Authentication delays must stay below 100 ms to meet VANET requirements, posing a major challenge for security. Our previous research introduced a Kerberos–Blockchain (KBC) authentication system that contains two main components separately: Authentication Server (AS) and Ticket Granting Server (TGS). However, this KBC architecture required an additional server to accommodate increasing vehicle volumes in urban environments, leading to higher infrastructure costs. This paper presents an integrated authentication server that merges AS and TGS into a Combined Server (CBS) while retaining blockchain security. We evaluate it using OMNeT++ with SUMO for traffic simulation and Ganache for blockchain implementation. Results show that CBS removes the need for an extra server while keeping authentication delays under 100 ms. It also improves throughput by 104% and reduces signaling overhead by 45% compared to KBC. By optimizing authentication without compromising security, the integrated server greatly enhances the cost-effectiveness and efficiency of VANET systems. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1424-8220 26 5 2026 A Proposal of Secure and Automated Over-the-Air Firmware Update Mechanism for IoT Devices Using Continuous Integration and Continuous Delivery 1535 EN Noprianto Department of Information and Communication Systems, Okayama University Nobuo Funabiki Department of Information and Communication Systems, Okayama University Htoo Htoo Sandi Kyaw Department of Information and Communication Systems, Okayama University Komang Candra Brata Department of Information and Communication Systems, Okayama University I Nyoman Darma Kotama Department of Information and Communication Systems, Okayama University The Internet of Things (IoT) technology has grown rapidly over the past decade, resulting in deployments of thousands of IoT devices around the world. Then, managing firmware updates for these numerous devices poses significant challenges. Firmware updates face issues such as version rollback, modified firmware files, and potential man-in-the-middle (MITM) attacks, highlighting the need for a secure over-the-air (OTA) firmware update mechanism. In this paper, we propose an automated OTA firmware update mechanism, integrated with continuous integration (CI) and continuous delivery (CD) to ensure trusted sources for firmware origins. It offers security, error handling during firmware updates, and monitoring of the update process. For evaluations, we implemented the proposal with the SEMAR IoT application server that has been implemented in our previous studies. Then, we verified the integrity and authentication, measured the performance and resource utilization, and performed benchmarking tests to assess the efficiency. The results demonstrate that the proposal is sufficiently reliable and efficient. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers (IEEE) Acta Medica Okayama 2169-3536 14 2026 FEM-Based Design and Characterization of a Millimeter-Scale Piezoelectric Resonance Force Sensor 17960 17970 EN Aoto Yamazaki Department of Mechanical Engineering, Toyohashi University of Technology Takuma Akiduki Department of Mechanical Engineering, Toyohashi University of Technology Atsuo Honna Riccoh Company Ltd. Michiteru Kitazaki Department of Computer Science and Engineering, Toyohashi University of Technology Tomoaki Mashimo Graduate School of Natural Science and Technology, Okayama University This paper presents a millimeter-scale piezoelectric effect-based force sensor that uses the change in its resonant frequency as the detection principle for high sensitivity and a wide measurement range. Such characteristics are suited for robot hand applications that not only detect small forces but also handle large payloads. We develop a methodology to estimate the relationship between applied force and resonant frequency shift by combining classical contact theory and finite element method (FEM) analysis. Although this relationship is non-linear, the designability of sensitivity and measurement range is demonstrated by the simulation. The simulation results based on the method are verified, showing good agreement with the experimental results. The static characteristics, including sensitivity, standard deviation, and resolution, are evaluated using prototype sensors with characteristic lengths ranging from 1 mm to 4 mm. The 4-mm model has a measurement range of 77 mN to 300 N, and the smallest model, which is one of the smallest force sensors suitable for practical implementation, has a measurement range of 9 mN to 20 N. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers (IEEE) Acta Medica Okayama 2644-1349 6 2026 Ultrafast Time-Compressive CMOS Image Sensors Based on Multitap Charge Modulators for Filming Light-In Flight 47 60 EN Keiichiro Kagawa Research Institute of Electronics, Shizuoka University Daisuke Hayashi Graduate School of Integrated Science and Technology, Shizuoka University Arashi Takakura Faculty of Engineering, Shizuoka University Yuto Umeki Graduate School of Integrated Science and Technology, Shizuoka University Michitaka Yoshida Faculty of Environmental, Life, Natural Science and Technology, Okayama University Keita Yasutomi Research Institute of Electronics, Shizuoka University Shoji Kawahito Research Institute of Electronics, Shizuoka University Youngcheol Chae Department of Electrical and Electronic Engineering, Yonsei University Hajime Nagahara D3 Center, The University of Osaka Ultrafast time-compressive CMOS image sensors based on multitap charge modulators can capture light-in flight using coded exposure masks on the focal plane. Transient images can then be reconstructed using iterative methods or deep learning models. Although the image sensor is based on indirect time-of-flight (ToF) image sensors, the reconstructed images are equivalent to those captured by direct ToF (D-ToF) image sensors. Important design parameters of the image sensor include the pixel block size and the number of taps of the charge modulator. Several constraints regarding the charge transfer of the multitap charge modulator, the hamming distance between exposure codes at adjacent timings, and the minimal time window duration must be considered when designing exposure codes. The influence of these factors on the fidelity of the reconstructed images is analyzed numerically. The results show that a pixel block size of 4×4 is optimal and that four or more taps are required for light detection and ranging (LiDAR) applications when 32 transient images of light-in flight are reconstructed. To demonstrate LiDAR in a scene with multipath interference, two objects were observed through a weakly diffusive sheet. The temporal resolution, as defined by the clock period of the exposure codes, was 1.65 ns. Multiple reflections were reconstructed using an iterative method (TVAL3) and a deep learning model (ADMM-Net). Although the waveforms of optical pulses reconstructed by TVAL3 are distorted, the amplitudes are more accurate. Conversely, although ADMM-Net reconstructs sharper optical pulses, the amplitudes are inaccurate. To achieve the shorter temporal resolution required for time-resolved diffuse optical tomography (DOT) and fluorescence lifetime imaging (FLIm), the feasibility of heterodyne compression was demonstrated through simulation. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1424-8220 26 4 2026 A Generative AI–Based Technical Data Extraction Tool for IoT Application Systems 1081 EN Dezheng Kong Department of Information and Communication Systems, Okayama University Nobuo Funabiki Department of Information and Communication Systems, Okayama University Htoo Htoo Sandi Kyaw Department of Information and Communication Systems, Okayama University I Nyoman Darma Kotama Department of Information and Communication Systems, Okayama University Zihao Zhu Department of Information and Communication Systems, Okayama University Alfiandi Aulia Rahmadani Department of Information and Communication Systems, Okayama University Nowadays, Internet of Things (IoT) application systems play an essential role in smart cities, industry, healthcare, agriculture, and smart homes. For non-expert users, designing and implementing IoT application systems remains challenging, especially when configuring sensors, edge devices, and server platforms. To support configuration tasks of IoT application systems, we have developed an AI-based setup assistance tool. However, AI models still fail to reliably support newly released or previously unseen devices, sometimes producing incomplete or erroneous outputs that may lead to configuration failures. Incorporating their technical-document information into Retrieval-Augmented Generation (RAG) is an effective way to supplement AI knowledge and improve reliability. In this paper, we propose a generative AI-based technical data extraction tool to address the challenges. It extracts essential technical information using the schema-based extraction from given PDF or HTML datasheets and converts it into a structured format suitable for AI-supported configurations. A local vector database is used to enable semantic similarity retrieval and provide document-grounded evidence for RAG-based answering, ensuring consistent support for previously unseen IoT devices. For evaluations, we applied the proposal to several sensor and device datasheets and compared extracted specifications with ground-truth values to measure accuracy and completeness. Then, we compared end-to-end configuration QA reliability against a commercial baseline (ChatPDF) using the golden benchmark. The results show that the proposed tool reliably acquires key specifications and significantly improves end-to-end configuration QA reliability. Across 960 golden QA pairs, the proposed method improves Recall from 0.636 to 0.926 and Accuracy from 0.595 to 0.807 compared with ChatPDF. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2079-9292 14 24 2025 An AI-Driven System for Learning MQTT Communication Protocols with Python Programming 4967 EN Zihao Zhu Department of Information and Communication Systems, Okayama University Nobuo Funabiki Department of Information and Communication Systems, Okayama University Htoo Htoo Sandi Kyaw Department of Information and Communication Systems, Okayama University I Nyoman Darma Kotama Department of Information and Communication Systems, Okayama University Anak Agung Surya Pradhana Department of Information and Communication Systems, Okayama University Alfiandi Aulia Rahmadani Department of Information and Communication Systems, Okayama University Noprianto Department of Information and Communication Systems, Okayama University With rapid developments of wireless communication and Internet of Things (IoT) technologies, an increasing number of devices and sensors are interconnected, generating massive amounts of data in real time. Among the underlying protocols, Message Queuing Telemetry Transport (MQTT) has become a widely adopted lightweight publish–subscribe standard due to its simplicity, minimal overhead, and scalability. Then, understanding such protocols is essential for students and engineers engaging in IoT application system designs. However, teaching and learning MQTT remains challenging for them. Its asynchronous architecture, hierarchical topic structure, and constituting concepts such as retained messages, Quality of Service (QoS) levels, and wildcard subscriptions are often difficult for beginners. Moreover, traditional learning resources emphasize theory and provide limited hands-on guidance, leading to a steep learning curve. To address these challenges, we propose an AI-assisted, exercise-based learning platform for MQTT. This platform provides interactive exercises with intelligent feedback to bridge the gap between theory and practice. To lower the barrier for learners, all code examples for executing MQTT communication are implemented in Python for readability, and Docker is used to ensure portable deployments of the MQTT broker and AI assistant. For evaluations, we conducted a usability study using two groups. The first group, who has no prior experience, focused on fundamental concepts with AI-guided exercises. The second group, who has relevant background, engaged in advanced projects to apply and reinforce their knowledge. The results show that the proposed platform supports learners at different levels, reduces frustrations, and improves both engagement and efficiency. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1687-8728 2026 1 2026 Experimental Analysis of Automatic Discrimination Performance Between Simulated Bruxism and Non‐Bruxism Under Conscious Conditions Using Electromyography and Machine Learning 7874254 EN Hajime Minakuchi Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Mitsuhiro Nagasaki Department of Electrical Engineering and Information Systems, Graduate School of Engineering, The University of Tokyo Lộc Hoàng Đình Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Haruna Miki Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ko Omori Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tazuko Nishimura Department of Electrical Engineering and Information Systems, Graduate School of Engineering, The University of Tokyo Takuo Kuboki Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuaki Minematsu Department of Electrical Engineering and Information Systems, Graduate School of Engineering, The University of Tokyo Purpose: This study aimed to evaluate the potential use of machine learning to automatically classify electromyography (EMG) data into bruxism simulated movement with tooth contact (BMwTC), bruxism simulated movement without tooth contact (BMwoTC), and non-bruxism movement (non-BM).<br> Methods: Twelve eligible healthy participants (female/male: 2/10, mean age: 35.3 ± 8.4 years) were asked to perform the simulated movements (all the tasks were performed five times for 5 s each with a 30-s rest interval). The electrodes were placed on the masseter, infrahyoid, inframandibular, and chin muscles. A sound sensor was placed adjacent to the masseter. The EMG and sound data were sampled at 1 and 44.1 kHz, respectively. Single- and multi-stream hidden Markov models (HMMs) were used to automatically discriminate the tested behavior from the others using a hamming window with 100 ms and shift length of 50 ms. The leave-one-out method was used for training and testing the model, with data from 11 participants used for training and one for testing. Each participant was evaluated, and the final performance was measured by averaging the results of 12 classification trials. The validity of the discrimination was assessed by calculating the harmony mean values using six EMG signals and the sound data.<br> Results: The masseter EMG demonstrated significantly higher discrimination accuracy in the single-stream model (p  < 0.05, One-way ANOVA, Tukey HDS). The multi-stream model also demonstrated higher accuracy; however, no significant difference was observed. Notably, the accuracy of BMwoTC was less than 0.5.<br> Conclusion: The machine-learning-based discriminative system accurately discriminates BMwTC from non-BM using masseter EMG. No potential conflict of interest relevant to this article was reported.

Fuji Technology Press Ltd. Acta Medica Okayama 1883-8049 37 6 2025 Directed Poisoning Attacks on FRIT in Adaptive Cruise Control 1392 1399 EN Taichi Ikezaki Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kenji Sawada Graduate school of Mechanical Engineering, The University of Osaka Osamu Kaneko Graduate School of Informatics and Engineering, The University of Electro-Communications Recent advances in connected-vehicle technologies have enabled the large-scale collection of driving data, facilitating the deployment of data-driven control schemes. Although these methods offer advantages by eliminating the need for explicit modeling, they also introduce vulnerabilities due to their reliance on stored data. This study investigates a class of targeted data poisoning attacks on fictitious reference iterative tuning, a widely used data-driven controller tuning approach. We present a method that allows an adversary to influence closed-loop dynamics by manipulating the training data so that the resulting controller behavior matches a maliciously defined reference response. This strategy differs from conventional poisoning attacks, which aim only to the degrade control performance. Instead, it enables deliberate alteration of control characteristics such as overshoot and convergence time. The proposed attack is formulated as a constrained optimization problem under bounded tampering signals. Through a numerical study involving adaptive cruise control with stop functionality, we show that minor data modifications, indistinguishable from sensor noise, can cause significant degradation in control behavior. These findings highlight the need for robust security mechanisms in data-driven control implementation. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2624-831X 6 3 2025 An Extension of Input Setup Assistance Service Using Generative AI to Unlearned Sensors for the SEMAR IoT Application Server Platform 52 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 Information Science and Technology, The University of Osaka 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 Nowadays, Internet of Things (IoT) application systems are broadly applied to various sectors of society for efficient management by monitoring environments using sensors, analyzing sampled data, and giving proper feedback. For their fast deployment, we have developed Smart Environmental Monitoring and Analysis in Real Time (SEMAR) as an integrated IoT application server platform and implemented the input setup assistance service using prompt engineering and a generative AI model to assist connecting sensors to SEMAR with step-by-step guidance. However, the current service cannot assist in connections of the sensors not learned by the AI model, such as newly released ones. To address this issue, in this paper, we propose an extension to the service for handling unlearned sensors by utilizing datasheets with four steps: (1) users input a PDF datasheet containing information about the sensor, (2) key specifications are extracted from the datasheet and structured into markdown format using a generative AI, (3) this data is saved to a vector database using chunking and embedding methods, and (4) the data is used in Retrieval-Augmented Generation (RAG) to provide additional context when guiding users through sensor setup. Our evaluation with five generative AI models shows that OpenAI’s GPT-4o achieves the highest accuracy in extracting specifications from PDF datasheets and the best answer relevancy (0.987), while Gemini 2.0 Flash delivers the most balanced results, with the highest overall RAGAs score (0.76). Other models produced competitive but mixed outcomes, averaging 0.74 across metrics. The step-by-step guidance function achieved a task success rate above 80%. In a course evaluation by 48 students, the system improved the student test scores, further confirming the effectiveness of our proposed extension. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1472-6831 25 1 2025 Phosphorylated pullulan as a local drug delivery matrix for cationic antibacterial chemicals to prevent oral biofilm 1333 EN Naoko Namba-Koide Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Yasuhiro Yoshida Department of Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School Takumi Okihara Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Yusuke Kawata Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Masahiro Ito Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Takashi Ito Center for Innovative Clinical Medicine, Okayama University Hospital Kazu Takeuchi-Hatanaka Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Yuki Shinoda-Ito Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazuhiro Omori Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadashi Yamamoto Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shogo Takashiba Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background Preventing oral infections, such as oral caries and periodontal disease, helps reduce the risks of various systemic diseases. In this study, the polysaccharide pullulan produced by the black yeast Aureobasidium pullulans was modified in combination with the cationic surfactant cetylpyridinium chloride (CPC) to create a local drug delivery system, and its antibacterial potential on oral bacteria was examined in vitro.<br> Methods Pullulan was phosphorylated at the CH2OH residue of α6 in the maltotriose structure and mixed with CPC. Bacterial attachment of cariogenic Streptococcus mutans on hydroxyapatite plates (HAPs) treated with the phosphorylated pullulan (PP) and CPC compound (0.01% PP and 0.001– 0.03% CPC, and vice versa) was assessed by observing bacteria using a field emission scanning electron microscope (FE-SEM) and quantified through 16 S rRNA amplification via real-time polymerase chain reaction (PCR). Additionally, the quartz crystal microbalance (QCM) method was employed to evaluate the sustained release of CPC.<br> Results PP-CPC compound maintained significant bactericidal activity even at 0.01%, which is one-fifth of the conventional applicable concentration of CPC. Additionally, a residual mixture was detected by the hydroxyapatite sensor of the crystal oscillator microbalance detector, suggesting an unknown molecular interaction that enables the sustained release of CPC after attachment to hydroxyapatite.<br> Conclusions The combination of PP and CPC may contribute to the low concentration and effective prevention of oral infections, such as dental caries. 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 0924-4247 390 2025 Extension-type flexible pneumatic actuator with a large extension force using a cross-link mechanism based on pantographs 116594 EN So Shimooka Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kazuma Tadachi Mechanical and Systems Engineering Program, School of Engineering, Okayama University Tetsushi Kamegawa Faculty of Environmental, Life, Natural Science and Technology, Okayama University In this study, we propose an extension-type flexible pneumatic actuator (EFPA) with a high extension force and no buckling. In a previous study, soft actuators that extended in the axial direction by applying a supply pressure were unable to generate the extension’s pushing force because the actuators buckled owing to their high flexibility. To generate a pushing force, the circumferential stiffness of an extension-type flexible soft actuator must be reinforced. Therefore, a cross-linked EFPA (CL-EFPA) was developed, inspired by a pantograph that restrains the EFPA three-dimensionally using the proposed link mechanism. The proposed CL-EFPA consists of three EFPAs and a cross-linking mechanism for integrating each EFPA circumference. The pushing force of the CL-EFPA is approximately 3.0 times compared with that generated by the previous EFPA with plates to restrain its plane. To perform various bending motions, attitude control was performed using an analytical model and a system that included valves, sensors, and controllers. No potential conflict of interest relevant to this article was reported.

IOS Press Acta Medica Okayama 0926-9630 2025 Trend of Digital Biomarkers (dBM) as Endpoints in Clinical Trials: Secondary Analysis of Open Data 391 395 EN Mizuki Morita Department of Biomedical Informatics, Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mina Honjoh Faculty of Health Sciences, Okayama University Medical School Takahiro Yamane Department of Biomedical Informatics, Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University This study examined clinical trial trends to guide digital biomarker (dBM) guideline development. Analysis of 2005–2023 data was conducted to assess the frequency and types of dBM used as endpoints (dEP) in these trials and the associated target diseases. Clinical trials using dEP increased from 0–7 per year (2005–2019) to 15–20 annually from 2020. Endocrine and metabolic conditions were the most common targets, showing a distinct disease distribution compared to overall trials. Most measurements used actigraphy devices or blood glucose sensors, with glucose sensors focusing on metabolic conditions while actigraphy covered broader applications. Additionally, 42.4% of trials used dEP as primary endpoints. While dEP use is growing, it remains limited in disease scope and device variety. Expanding both would enhance their utility in clinical research. 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.

American Chemical Society (ACS) Acta Medica Okayama 1554-8929 19 12 2024 Discovery of a Compound That Inhibits IRE1α S-Nitrosylation and Preserves the Endoplasmic Reticulum Stress Response under Nitrosative Stress 2429 2437 EN Haruna Kurogi 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 Sho Kubota Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ashutosh Kumar Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN Takehiro Suzuki Biomolecular Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science Naoshi Dohmae Biomolecular Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science Daisuke Sawada Department of Fine Organic Synthesis, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kam Y.J. Zhang Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Inositol-requiring enzyme 1α (IRE1α) is a sensor of endoplasmic reticulum (ER) stress and drives ER stress response pathways. Activated IRE1α exhibits RNase activity and cleaves mRNA encoding X-box binding protein 1, a transcription factor that induces the expression of genes that maintain ER proteostasis for cell survival. Previously, we showed that IRE1α undergoes S-nitrosylation, a post-translational modification induced by nitric oxide (NO), resulting in reduced RNase activity. Therefore, S-nitrosylation of IRE1α compromises the response to ER stress, making cells more vulnerable. We conducted virtual screening and cell-based validation experiments to identify compounds that inhibit the S-nitrosylation of IRE1α by targeting nitrosylated cysteine residues. We ultimately identified a compound (1ACTA) that selectively inhibits the S-nitrosylation of IRE1α and prevents the NO-induced reduction of RNase activity. Furthermore, 1ACTA reduces the rate of NO-induced cell death. Our research identified S-nitrosylation as a novel target for drug development for IRE1α and provides a suitable screening strategy. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1424-8220 25 12 2025 Effects of Sampling Frequency on Human Activity Recognition with Machine Learning Aiming at Clinical Applications 3780 EN Takahiro Yamane Department of Biomedical Informatics, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Moeka Kimura Faculty of Health Sciences, Okayama University Medical School Mizuki Morita Department of Biomedical Informatics, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Human activity recognition using wearable accelerometer data can be a useful digital biomarker for severity assessment and the diagnosis of diseases, where the relationship between onset and patient activity is crucial. For long-term monitoring in clinical settings, the volume of data collected over time should be minimized to reduce power consumption, computational load, and communication volume. This study aimed to determine the lowest sampling frequency that maintains recognition accuracy for each activity. Thirty healthy participants wore nine-axis accelerometer sensors at five body locations and performed nine activities. Machine-learning-based activity recognition was conducted using data sampled at 100, 50, 25, 20, 10, and 1 Hz. Data from the non-dominant wrist and chest, which have previously shown high recognition accuracy, were used. Reducing the sampling frequency to 10 Hz did not significantly affect the recognition accuracy for either location. However, lowering the frequency to 1 Hz decreases the accuracy of many activities, particularly brushing teeth. Using data with a 10 Hz sampling frequency can maintain recognition accuracy while decreasing data volume, enabling long-term patient monitoring and device miniaturization for clinical applications. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 25 7 2025 Length Estimation of Pneumatic Artificial Muscle with Optical Fiber Sensor Using Machine Learning 2221 EN Yilei Ni Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shuichi Wakimoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Weihang Tian Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuichiro Toda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takefumi Kanda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Daisuke Yamaguchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University A McKibben artificial muscle is a soft actuator driven by air pressure, characterized by its flexibility, lightweight design, and high power-to-weight ratio. We have developed a smart artificial muscle that is capable of sensing its motion. To enable this sensing function, an optical fiber was integrated into the sleeve consisting of multiple fibers and serving as a component of the McKibben artificial muscle. By measuring the macrobending loss of the optical fiber, the length of the smart artificial muscle is expected to be estimated. However, experimental results indicated that the sensor's characteristics depend not only on the length but also on the load and the applied air pressure. This dependency arises because the stress applied to the optical fiber increases, causing microbending loss. In this study, we employed a machine learning model, primarily composed of Long Short-Term Memory (LSTM) neural networks, to estimate the length of the smart artificial muscle. The experimental results demonstrate that the length estimation obtained through machine learning exhibits a smaller error. This suggests that machine learning is a feasible approach to enhancing the length measurement accuracy of the smart artificial muscle. 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.

MDPI Acta Medica Okayama 2224-2708 14 1 2024 Enhancing Campus Environment: Real-Time Air Quality Monitoring Through IoT and Web Technologies 2 EN Alfiandi Aulia Rahmadani Department of Electrical Engineering, State Polytechnic of Malang Yan Watequlis Syaifudin Department of Information Technology, State Polytechnic of Malang Budhy Setiawan Department of Electrical Engineering, State Polytechnic of Malang Yohanes Yohanie Fridelin Panduman Department of Information and Communication Systems, Okayama University Nobuo Funabiki Department of Information and Communication Systems, Okayama University Nowadays, enhancing campus environments through mitigations of air pollutions is an essential endeavor to support academic achievements, health, and safety of students and staffs in higher educational institutes. In laboratories, pollutants from welding, auto repairs, or chemical experiments can drastically degrade the air quality in the campus, endangering the respiratory and cognitive health of students and staffs. Besides, in universities in Indonesia, automobile emissions of harmful substances such as carbon monoxide (CO), nitrogen dioxide (NO2), and hydrocarbon (HC) have been a serious problem for a long time. Almost everybody is using a motorbike or a car every day in daily life, while the number of students is continuously increasing. However, people in many campuses including managements do not be aware these problems, since air quality is not monitored. In this paper, we present a real-time air quality monitoring system utilizing Internet of Things (IoT) integrated sensors capable of detecting pollutants and measuring environmental conditions to visualize them. By transmitting data to the SEMAR IoT application server platform via an ESP32 microcontroller, this system provides instant alerts through a web application and Telegram notifications when pollutant levels exceed safe thresholds. For evaluations of the proposed system, we adopted three sensors to measure the levels of CO, NO2, and HC and conducted experiments in three sites, namely, Mechatronics Laboratory, Power and Emission Laboratory, and Parking Lot, at the State Polytechnic of Malang, Indonesia. Then, the results reveal Good, Unhealthy, and Dangerous for them, respectively, among the five categories defined by the Indonesian government. The system highlighted its ability to monitor air quality fluctuations, trigger warnings of hazardous conditions, and inform the campus community. The correlation of the sensor levels can identify the relationship of each pollutant, which provides insight into the characteristics of pollutants in a particular scenario. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 79 1 2025 Endothelial Cell Polarity in Health and Disease 1 7 EN Moe Thiha Department of Pathophysiology and Drug Discovery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takao Hikita Department of Pathophysiology and Drug Discovery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masanori Nakayama Department of Pathophysiology and Drug Discovery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Review 10.18926/AMO/68353 Endothelial cell polarity is fundamental to the organization and function of blood vessels, influencing processes such as angiogenesis, vascular stability, and response to shear stress. This review elaborates on the molecular mechanisms that regulate endothelial cell polarity, focusing on key players like the PAR polarity complex and Rho family GTPases. These pathways coordinate the front–rear, apical–basal and planar polarity of endothelial cells, which are essential for the proper formation and maintenance of vascular structures. In health, endothelial polarity ensures not only the orderly development of blood vessels, with tip cells adopting distinct polarities during angiogenesis, but also ensures proper vascular integrity and function. In disease states, however, disruptions in polarity contribute to pathologies such as coronary artery disease, where altered planar polarity exacerbates atherosclerosis, and cancer, where disrupted polarity in tumor vasculature leads to abnormal vessel growth and function. Understanding cell polarity and its disruption is fundamental not only to comprehending how cells interact with their microenvironment and organize themselves into complex, organ-specific tissues but also to developing novel, targeted, and therapeutic strategies for a range of diseases, from cardiovascular disorders to malignancies, ultimately improving patient outcomes. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2079-9292 14 2 2025 A Proposal of In Situ Authoring Tool with Visual-Inertial Sensor Fusion for Outdoor Location-Based Augmented Reality 342 EN Komang Candra Brata Department of Information and Communication Systems, Okayama University Nobuo Funabiki Department of Information and Communication Systems, Okayama University Yohanes Yohanie Fridelin Panduman Department of Information and Communication Systems, Okayama University Mustika Mentari Department of Information and Communication Systems, Okayama University Yan Watequlis Syaifudin Department of Information Technology, Politeknik Negeri Malang Alfiandi Aulia Rahmadani Department of Information Technology, Politeknik Negeri Malang In location-based augmented reality (LAR) applications, a simple and effective authoring tool is essential to create immersive AR experiences in real-world contexts. Unfortunately, most of the current tools are primarily desktop-based, requiring manual location acquisitions, the use of software development kits (SDKs), and high programming skills, which poses significant challenges for novice developers and a lack of precise LAR content alignment. In this paper, we propose an intuitive in situ authoring tool with visual-inertial sensor fusions to simplify the LAR content creation and storing process directly using a smartphone at the point of interest (POI) location. The tool localizes the user’s position using smartphone sensors and maps it with the captured smartphone movement and the surrounding environment data in real-time. Thus, the AR developer can place a virtual object on-site intuitively without complex programming. By leveraging the combined capabilities of Visual Simultaneous Localization and Mapping(VSLAM) and Google Street View (GSV), it enhances localization and mapping accuracy during AR object creation. For evaluations, we conducted extensive user testing with 15 participants, assessing the task success rate and completion time of the tool in practical pedestrian navigation scenarios. The Handheld Augmented Reality Usability Scale (HARUS) was used to evaluate overall user satisfaction. The results showed that all the participants successfully completed the tasks, taking 16.76 s on average to create one AR object in a 50 m radius area, while common desktop-based methods in the literature need 1–8 min on average, depending on the user’s expertise. Usability scores reached 89.44 for manipulability and 85.14 for comprehensibility, demonstrating the high effectiveness in simplifying the outdoor LAR content creation process. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1936-0851 18 52 2024 Bright Quantum-Grade Fluorescent Nanodiamonds 35202 35213 EN Keisuke Oshimi Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Hitoshi Ishiwata The National Institutes for Quantum Science and Technology (QST), Institute for Quantum Life Science (iQLS) Hiromu Nakashima Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Sara Mandić Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Hina Kobayashi Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Minori Teramoto Advanced Materials Laboratory, Sumitomo Electric Industries, Ltd. Hirokazu Tsuji Advanced Materials Laboratory, Sumitomo Electric Industries, Ltd. Yoshiki Nishibayashi Advanced Materials Laboratory, Sumitomo Electric Industries, Ltd. Yutaka Shikano Institute of Systems and Information Engineering, University of Tsukuba Toshu An School of Materials Science, Japan Advanced Institute of Science and Technology Masazumi Fujiwara Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Optically accessible spin-active nanomaterials are promising as quantum nanosensors for probing biological samples. However, achieving bioimaging-level brightness and high-quality spin properties for these materials is challenging and hinders their application in quantum biosensing. Here, we demonstrate bright fluorescent nanodiamonds (NDs) containing 0.6–1.3-ppm negatively charged nitrogen-vacancy (NV) centers by spin-environment engineering via enriching spin-less 12C-carbon isotopes and reducing substitutional nitrogen spin impurities. The NDs, readily introduced into cultured cells, exhibited improved optically detected magnetic resonance (ODMR) spectra; peak splitting (E) was reduced by 2–3 MHz, and microwave excitation power required was 20 times lower to achieve a 3% ODMR contrast, comparable to that of conventional type-Ib NDs. They show average spin-relaxation times of T1 = 0.68 ms and T2 = 3.2 μs (1.6 ms and 5.4 μs maximum) that were 5- and 11-fold longer than those of type-Ib, respectively. Additionally, the extended T2 relaxation times of these NDs enable shot-noise-limited temperature measurements with a sensitivity of approximately 0.28K/√Hz. The combination of bulk-like NV spin properties and enhanced fluorescence significantly improves the sensitivity of ND-based quantum sensors for biological applications. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2635-0998 2 3 2023 All-in-one terahertz taste sensor: integrated electronic and bioelectronic tongues 620 626 EN 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 Taste sensors, also known as electronic tongues or bioelectronic tongues, are designed to evaluate food and beverages, as well as for medical diagnostics. These devices mimic the ability of the human tongue to detect and identify different tastes in liquid samples, such as sweet, sour, salty, bitter, and umami. In this study, a novel all-in-one terahertz taste sensor was proposed, which differs from traditional electrochemical approaches. This sensor utilizes terahertz technology for imaging and sensing chemical reactions on the terahertz semiconductor emitter surface. The surface can be functionalized with ion-sensitive membranes, proteins, DNA aptamers, and organic receptors, enabling the detection of various substances, such as solution pH, physiological ions, sugars, toxic chemicals, drugs, and explosives. Terahertz taste sensors offer several advantages, including being label-free, high sensitivity and selectivity, rapid response, minimal sample consumption, and the ability to detect non-charged chemical substances. By integrating multiple receptors or sensing materials on a single chip, the all-in-one terahertz taste sensor has significant potential for future taste substance detection, nutrition evaluation, metabolite and drug monitoring, and biomarker sensing. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 24 23 2024 The Design and Implementation of Kerberos-Blockchain Vehicular Ad-Hoc Networks Authentication Across Diverse Network Scenarios 7428 EN Maya Rahayu Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Md. Biplob Hossain Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Samsul Huda Green Innovation Center, Okayama University Yuta Kodera Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Md. Arshad Ali Faculty of CSE, Hajee Mohammad Danesh Science and Technology University Yasuyuki Nogami Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Vehicular Ad-Hoc Networks (VANETs) play an essential role in the intelligent transportation era, furnishing users with essential roadway data to facilitate optimal route selection and mitigate the risk of accidents. However, the network exposure makes VANETs susceptible to cyber threats, making authentication crucial for ensuring security and integrity. Therefore, joining entity verification is essential to ensure the integrity and security of communication in VANETs. However, to authenticate the entities, authentication time should be minimized to guarantee fast and secure authentication procedures. We propose an authentication system for VANETs using blockchain and Kerberos for storing authentication messages in a blockchain ledger accessible to Trusted Authentication Servers (TASs) and Roadside Units (RSUs). We evaluate the system in three diverse network scenarios: suburban, urban with 1 TAS, and urban with 2 TASs. The findings reveal that this proposal is applicable in diverse network scenarios to fulfill the network requirements, including authentication, handover, and end-to-end delay, considering an additional TAS for an increasing number of vehicles. The system is also practicable in storing the authentication message in blockchain considering the gas values and memory size for all scenarios. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 24 22 2024 Microdetection of Nucleocapsid Proteins via Terahertz Chemical Microscope Using Aptamers 7382 EN Xue Ding Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mana Murakami 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 Hirofumi Inoue Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama University Hospital Toshihiko Kiwa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University In the detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several methods have been employed, including the detection of viral ribonucleic acid (RNA), nucleocapsid (N) proteins, spike proteins, and antibodies. RNA detection, primarily through polymerase chain reaction tests, targets the viral genetic material, whereas antigen tests detect N and spike proteins to identify active infections. In addition, antibody tests are performed to measure the immune response, indicating previous exposure or vaccination. Here, we used the developed terahertz chemical microscope (TCM) to detect different concentrations of N protein in solution by immobilizing aptamers on a semiconductor substrate (sensing plate) and demonstrated that the terahertz amplitude varies as the concentration of N proteins increases, exhibiting a highly linear relationship with a coefficient of determination (R2 = 0.9881), indicating that a quantitative measurement of N proteins is achieved. By optimizing the reaction conditions, we confirmed that the amplitude of the terahertz wave was independent of the solution volume. Consequently, trace amounts (0.5 μL) of the N protein were successfully detected, and the detection process only took 10 min. Therefore, this study is expected to develop a rapid and sensitive method for the detection and observation of the SARS-CoV-2 virus at a microdetection level. It is anticipated that this research will significantly contribute to reducing the spread of novel infectious diseases in the future. No potential conflict of interest relevant to this article was reported.

九州工業大学ケアXDXセンター Acta Medica Okayama 2759-2871 2024 1 2024 Abacus Manipulation Understanding by Behavior Sensing Utilizing Document Camera as a Sensor 2 EN Yuki MATSUDA Faculty of Environmental, Life, Natural Science and Technology Okayama University 　The abacus (also known as Soroban) is a numerical calculation tool that is traditionally used in East Asian countries. With the advancement of information technologies, the abacus is no longer used as a standard calculation tool. However, abacus learning is garnering global attention due to the secondary skills it can foster, e.g., mental arithmetic ability. Numerical calculation using an abacus requires learning numerical expressions using the beads of the abacus and manipulating beads in multiple ways and in different orders. Due to this complexity, a long period of repeated learning is usually required to acquire the skill of using the abacus. However, the teaching method of the abacus mainly relied on lecturers' observation through finding errors and poor bead manipulations and pointing them out, and there is no other way but to rely on human labor at this moment. In this study, we aim to realize an ICT-based learning support system for arithmetic with a common abacus. This paper proposes a method of estimating input values on an abacus based on image recognition captured by a document camera. Through the evaluation experiments, we have confirmed that the proposed method showed an accuracy of 95.0% in the estimation of 7-digit number input on an abacus. Additionally, this paper will provide discussions to realize the proposed method with other cameras such as wearable camera devices, and to design the coaching system of abacus learning. No potential conflict of interest relevant to this article was reported.

MYU K.K. Acta Medica Okayama 0914-4935 36 10 2024 Mobile Augmented Reality Interface for Instruction-based Disaster Preparedness Guidelines 4585 4606 EN Sergio De León Aguilar Graduate School of Information Science, Nara Institute of Science and Technology Yuki Matsuda Faculty of Environmental, Life, Natural Science and Technology, Okayama University Keiichi Yasumoto Graduate School of Information Science, Nara Institute of Science and Technology Disaster preparedness guidelines help citizens protect themselves against disasters. Nonetheless, the general public has been found not to read them. Augmented reality (AR) interfaces are known to improve knowledge transfer in studies of education, industry, and elderly assistance. However, this is achieved this by creating specific interfaces for users, not the general public. To test the performance of these interfaces for general public guidance, we designed and implemented a novel AR-assisted disaster prevention guideline that leverages object detection models to identify targets of disaster preparedness advice. We then had a diverse-age audience compare our design against a real traditional paper-based preparedness guide in a room arranged as a common remote work bedroom. By testing their usability, task load, and capacity to make users aware of their environmental hazards, we gained important insights into the performance of different age groups following media developed for the general public. Regardless of different age groups achieving similar usability scores, we found minors improving their performance scores with our novel interface and adults from 20 to 49 years old seemingly performing better than other age groups. In this study, we highlight the importance of guidance alternatives for the young and the less-technology-aware population, contributing to the under-explored area of AR interfaces for the general public. No potential conflict of interest relevant to this article was reported.

Society of Photo-optical Instrumentation Engineers Acta Medica Okayama 2329-4124 10 1 2024 Design and performance of a gain calibration system for the POLARBEAR-2a receiver system at the Simons Array cosmic microwave background experiment 018003 EN Daisuke Kaneko High Energy Accelerator Research Organization, International Center for Quantum-field Measurement Systems for Studies of the Universe and Particles Sayuri Takatori Okayama University, Research Institute for Interdisciplinary Science Masaya Hasegawa High Energy Accelerator Research Organization, International Center for Quantum-field Measurement Systems for Studies of the Universe and Particles Masashi Hazumi High Energy Accelerator Research Organization, International Center for Quantum-field Measurement Systems for Studies of the Universe and Particles Yuki Inoue National Central University, Center for High Energy and High Field Physics, Department of Physics Oliver Jeong University of California, Department of Physics Nobuhiko Katayama University of Tokyo, Kavli Institute for the Physics and Mathematics of the Universe Adrian T. Lee University of California, Department of Physics Frederick Matsuda Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science Haruki Nishino The University of Tokyo, Graduate School of Science, Research Center for the Early Universe Praween Siritanasak National Astronomical Research Institute of Thailand Aritoki Suzuki Lawrence Berkeley National Laboratory, Physics Division Satoru Takakura Kyoto University, Department of Physics, Faculty of Science Takayuki Tomaru National Astronomical Observatory of Japan, Gravitational Wave Project Office We present an advanced system for calibrating the detector gain responsivity with a chopped thermal source for POLARBEAR-2a, which is the first receiver system of a cosmic microwave background (CMB) polarimetry experiment: the Simons Array. Intensity-to-polarization leakage due to calibration errors between detectors can be a significant source of systematic error for a polarization-sensitive experiment. To suppress this systematic uncertainty, POLARBEAR-2a calibrates the detector gain responsivities by observing a chopped thermal source before and after each period of science observations. The system includes a high-temperature ceramic heater that emits blackbody radiation covering a wide frequency range and an optical chopper to modulate the radiation signal. We discuss the experimental requirements of gain calibration and system design to calibrate POLARBEAR-2a. We evaluate the performance of our system during the early commissioning of the receiver system. This calibration system is promising for the future generation of CMB ground-based polarization observations. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2079-9292 13 14 2024 A Reference Paper Collection System Using Web Scraping 2700 EN Inzali Naing Department of Information and Communication Systems, Okayama University Soe Thandar Aung Department of Information and Communication Systems, Okayama University Khaing Hsu Wai Department of Information and Communication Systems, Okayama University Nobuo Funabiki Department of Information and Communication Systems, Okayama University Collecting reference papers from the Internet is one of the most important activities for progressing research and writing papers about their results. Unfortunately, the current process using Google Scholar may not be efficient, since a lot of paper files cannot be accessed directly by the user. Even if they are accessible, their effectiveness needs to be checked manually. In this paper, we propose a reference paper collection system using web scraping to automate paper collections from websites. This system can collect or monitor data from the Internet, which is considered as the environment, using Selenium, a popular web scraping software, as the sensor; this examines the similarity against the search target by comparing the keywords using the Bert model. The Bert model is a deep learning model for natural language processing (NLP) that can understand context by analyzing the relationships between words in a sentence bidirectionally. The Python Flask is adopted at the web application server, where Angular is used for data presentations. For the evaluation, we measured the performance, investigated the accuracy, and asked members of our laboratory to use the proposed method and provide their feedback. Their results confirm the method’s effectiveness. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 24 13 2024 Optimizing IoT Intrusion Detection Using Balanced Class Distribution, Feature Selection, and Ensemble Machine Learning Techniques 4293 EN Muhammad Bisri Musthafa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Samsul Huda Green Innovation Center, Okayama University Yuta Kodera Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Md. Arshad Ali Faculty of CSE, Hajee Mohammad Danesh Science and Technology University Shunsuke Araki Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology Jedidah Mwaura Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology Yasuyuki Nogami Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Internet of Things (IoT) devices are leading to advancements in innovation, efficiency, and sustainability across various industries. However, as the number of connected IoT devices increases, the risk of intrusion becomes a major concern in IoT security. To prevent intrusions, it is crucial to implement intrusion detection systems (IDSs) that can detect and prevent such attacks. IDSs are a critical component of cybersecurity infrastructure. They are designed to detect and respond to malicious activities within a network or system. Traditional IDS methods rely on predefined signatures or rules to identify known threats, but these techniques may struggle to detect novel or sophisticated attacks. The implementation of IDSs with machine learning (ML) and deep learning (DL) techniques has been proposed to improve IDSs' ability to detect attacks. This will enhance overall cybersecurity posture and resilience. However, ML and DL techniques face several issues that may impact the models' performance and effectiveness, such as overfitting and the effects of unimportant features on finding meaningful patterns. To ensure better performance and reliability of machine learning models in IDSs when dealing with new and unseen threats, the models need to be optimized. This can be done by addressing overfitting and implementing feature selection. In this paper, we propose a scheme to optimize IoT intrusion detection by using class balancing and feature selection for preprocessing. We evaluated the experiment on the UNSW-NB15 dataset and the NSL-KD dataset by implementing two different ensemble models: one using a support vector machine (SVM) with bagging and another using long short-term memory (LSTM) with stacking. The results of the performance and the confusion matrix show that the LSTM stacking with analysis of variance (ANOVA) feature selection model is a superior model for classifying network attacks. It has remarkable accuracies of 96.92% and 99.77% and overfitting values of 0.33% and 0.04% on the two datasets, respectively. The model's ROC is also shaped with a sharp bend, with AUC values of 0.9665 and 0.9971 for the UNSW-NB15 dataset and the NSL-KD dataset, respectively. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2055-5822 11 5 2024 Prediction of heart failure events based on physiologic sensor data in HINODE defibrillator patients 3322 3331 EN Nobuhiro Nishii Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasushi Sakata Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine Toyoaki Murohara Department of Cardiology, Nagoya University Graduate School of Medicine Kenji Ando Department of Cardiology, Kokura Memorial Hospital Takanori Ikeda Department of Cardiovascular Medicine, Toho University Faculty of Medicine Takeshi Mitsuhashi Department of Cardiology, Hoshi General Hospital Akihiko Nogami Department of Cardiology, Faculty of Medicine, University of Tsukuba Wataru Shimizu Department of Cardiovascular Medicine, Nippon Medical School Torri Schwartz Boston Scientific Torsten Kayser Boston Scientific Caroline Beaudoint Boston Scientific Kazutaka Aonuma Department of Cardiology, Faculty of Medicine, University of Tsukuba for HINODE Investigators Aims Hospitalizations are common in patients with heart failure and are associated with high mortality, readmission and economic burden. Detecting early signs of worsening heart failure may enable earlier intervention and reduce hospitalizations. The HeartLogic algorithm is designed to predict worsening heart failure using diagnostic data from multiple device sensors. The main objective of this analysis was to evaluate the sensitivity of the HeartLogic alert calculation in predicting worsening heart failure events (HFEs). We also evaluated the false positive alert rate (FPR) and compared the incidence of HFEs occurring in a HeartLogic alert state to those occurring out of an alert state. <br> Methods The HINODE study enrolled 144 patients (81 ICD and 63 CRT-D) with device sensor data transmitted via a remote monitoring system. HeartLogic alerts were then retrospectively simulated using relevant sensor data. Clinicians and patients were blinded to calculated alerts. Reported adverse events with HF symptoms were adjudicated and classified by an independent HFE committee. Sensitivity was defined as the ratio of the number of detected usable HFEs (true positives) to the total number of usable HFEs. A false positive alert was defined as an alert with no usable HFE between the alert onset date and the alert recovery date plus 30 days. The patient follow-up period was categorized as in alert state or out of alert state. The event rate ratio was the HFE rate calculated in alert to out of alert. <br> Results The patient cohort was 79% male and had an average age of 68 +/- 12 years. This analysis yielded 244 years of follow-up data with 73 HFEs from 37 patients. A total of 311 HeartLogic alerts at the nominal threshold (16) occurred across 106 patients providing an alert rate of 1.27 alerts per patient-year. The HFE rate was 8.4 times greater while in alert compared with out of alert (1.09 vs. 0.13 events per patient-year; P < 0.001). At the nominal alert threshold, 80.8% of HFEs were detected by a HeartLogic alert [95% confidence interval (CI): 69.9%-89.1%]. The median time from first true positive alert to an adjudicated clinical HFE was 53 days. The FPR was 1.16 (95% CI: 0.98-1.38) alerts per patient-year. <br> Conclusions Results suggest that signs of worsening HF can be detected successfully with remote patient follow-up. The use of HeartLogic may predict periods of increased risk for HF or clinically significant events, allowing for early intervention and reduction of hospitalization in a vulnerable patient population. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 59 17 2023 Non-enzymatic detection of glucose levels in human blood plasma by a graphene oxide-modified organic transistor sensor 2425 2428 EN Haonan Fan Institute of Industrial Science, The University of Tokyo Yui Sasaki Institute of Industrial Science, The University of Tokyo Qi Zhou Institute of Industrial Science, The University of Tokyo Wei Tang Institute of Industrial Science, The University of Tokyo Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Tsuyoshi Minami Institute of Industrial Science, The University of Tokyo We herein report an organic transistor functionalized with a phenylboronic acid derivative and graphene oxide for the quantification of plasma glucose levels, which has been achieved by the minimization of interferent effects derived from physical protein adsorption on the detection electrode. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 24 7 2024 An Application of Throughput Request Satisfaction Method for Maximizing Concurrent Throughput in WLAN for IoT Application System 2173 EN Bin Wu Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Sujan Chandra Roy Graduate School of Natural Science and Technology, Okayama University Md. Mahbubur Rahman Graduate School of Natural Science and Technology, Okayama University Dezheng Kong Graduate School of Natural Science and Technology, Okayama University Shihao Fang Graduate School of Natural Science and Technology, Okayama University With the wide applications of the Internet of Things (IoT) in smart home systems, IEEE 802.11n Wireless Local Area Networks (WLANs) have become a frequently chosen communication technology due to their adaptability and affordability. In a high-density network of devices such as the smart home scenerio, a host often meets interferences from other devices and unequal Received Signal Strength (RSS) from Access Points (APs). This results in throughput unfairness/insufficiency problems between hosts communicating concurrently in WLAN. Previously, we have studied the throughput request satisfaction method to address this problem. It calculates the target throughput from measured single and concurrent throughputs of hosts and controls the actual throughput at this target one by applying traffic shaping at the AP. However, the insufficiency problem of maximizing the throughput is not solved due to interferences from other hosts. In this paper, we present an extension of the throughput request satisfaction method to maximize the throughput of a high-priority host under concurrent communications. It recalculates the target throughput to increase the actual throughput as much as possible while the other hosts satisfy the least throughput. For evaluations, we conduct experiments using the test-bed system with Raspberry Pi as the AP devices in several topologies in indoor environments. The results confirm the effectiveness of our proposal. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2078-2489 15 3 2024 A Survey of AI Techniques in IoT Applications with Use Case Investigations in the Smart Environmental Monitoring and Analytics in Real-Time IoT Platform 153 EN Yohanes Yohanie Fridelin Panduman Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Evianita Dewi Fajrianti Graduate School of Natural Science and Technology, Okayama University Shihao Fang Graduate School of Natural Science and Technology, Okayama University Sritrusta Sukaridhoto Department of Informatic and Computer, Politeknik Elektronika Negeri Surabaya In this paper, we have developed the SEMAR (Smart Environmental Monitoring and Analytics in Real-Time) IoT application server platform for fast deployments of IoT application systems. It provides various integration capabilities for the collection, display, and analysis of sensor data on a single platform. Recently, Artificial Intelligence (AI) has become very popular and widely used in various applications including IoT. To support this growth, the integration of AI into SEMAR is essential to enhance its capabilities after identifying the current trends of applicable AI technologies in IoT applications. In this paper, we first provide a comprehensive review of IoT applications using AI techniques in the literature. They cover predictive analytics, image classification, object detection, text spotting, auditory perception, Natural Language Processing (NLP), and collaborative AI. Next, we identify the characteristics of each technique by considering the key parameters, such as software requirements, input/output (I/O) data types, processing methods, and computations. Third, we design the integration of AI techniques into SEMAR based on the findings. Finally, we discuss use cases of SEMAR for IoT applications with AI techniques. The implementation of the proposed design in SEMAR and its use to IoT applications will be in future works. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers Acta Medica Okayama 2169-3536 12 2024 WLAN Channel Status Duration Prediction for Audio and Video Services Using Probabilistic Neural Networks 28201 28211 EN Yafei Hou Faculty of Environmental, Life, Natural Science and Technology, Okayama University Satoshi Denno Faculty of Environmental, Life, Natural Science and Technology, Okayama University Due to massive increase in wireless access from smartphones, IoT devices, WLAN is aiming to improve its spectrum efficiency (SE) using many technologies. Some interesting techniques for WLAN systems are flexible allocation of frequency resource and cognitive radio (CR) techniques which expect to find more useful spectrum resource by modeling and then predicting of channel status using the captured statistics information of the used spectrum. This paper investigates the prediction accuracy of busy/idle duration of two major wireless services: audio service and video service using neural network based predictor. We first study the statistics distribution of their time-series busy/idle (B/I) duration, and then analyze the predictability of the busy/idle duration based on the predictability theory. Then, we propose a data categorization (DC) method which categorizes the duration of recent B/I duration according the their ranges to make the duration of next data be distributed into several streams. From the predictability analysis of each stream and the prediction performance using the probabilistic neural network (PNN), it can be confirmed that the proposed DC can improve the prediction accuracy of time-series data in partial streams. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 24 4 2024 An Enhancement of Outdoor Location-Based Augmented Reality Anchor Precision through VSLAM and Google Street View 1161 EN Komang Candra Brata 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 Evianita Dewi Fajrianti Graduate School of Natural Science and Technology, Okayama University Outdoor Location-Based Augmented Reality (LAR) applications require precise positioning for seamless integrations of virtual content into immersive experiences. However, common solutions in outdoor LAR applications rely on traditional smartphone sensor fusion methods, such as the Global Positioning System (GPS) and compasses, which often lack the accuracy needed for precise AR content alignments. In this paper, we introduce an innovative approach to enhance LAR anchor precision in outdoor environments. We leveraged Visual Simultaneous Localization and Mapping (VSLAM) technology, in combination with innovative cloud-based methodologies, and harnessed the extensive visual reference database of Google Street View (GSV), to address the accuracy limitation problems. For the evaluation, 10 Point of Interest (POI) locations were used as anchor point coordinates in the experiments. We compared the accuracies between our approach and the common sensor fusion LAR solution comprehensively involving accuracy benchmarking and running load performance testing. The results demonstrate substantial enhancements in overall positioning accuracies compared to conventional GPS-based approaches for aligning AR anchor content in the real world. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 24 2 2024 Ultrathin Platinum Film Hydrogen Sensors with a Twin-T Type Notch Filter Circuit 548 EN Shoki Wakabayashi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yuki Oh Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Haruhito Nakayama 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 Toshihiko Kiwa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University In recent years, hydrogen energy has garnered attention as a potential solution for mitigating greenhouse gas emissions. However, concerns regarding the inherent risk of hydrogen gas leakage and potential explosions have necessitated the development of advanced sensors. Within our research group, we have innovated an ultrathin platinum (Pt) film hydrogen sensor that gauges resistance changes in Pt thin films when exposed to hydrogen gas. Notably, the sensitivity of each sensor is contingent upon the thickness of the Pt film. To address the challenge of detecting hydrogen using multiple sensors, we integrated the ultrathin Pt film as a resistance element within a twin-T type notch filter. This filter exhibits a distinctive reduction in output signals at a specific frequency. The frequency properties of the notch filter dynamically alter with changes in the resistance of the Pt film induced by hydrogen exposure. Consequently, the ultrathin Pt film hydrogen sensor monitors output signal variations around the notch frequency, responding to shifts in frequency properties. This innovative approach enables the electrical control of sensor sensitivity by adjusting the operating frequency in proximity to the notch frequency. Additionally, the simultaneous detection of hydrogen by multiple sensors was successfully achieved by interconnecting sensors with distinct notch frequencies in series. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 1932-1058 17 5 2023 Diamond quantum sensors in microfluidics technology 054107 EN Masazumi Fujiwara Department of Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Diamond quantum sensing is an emerging technology for probing multiple physico-chemical parameters in the nano- to micro-scale dimensions within diverse chemical and biological contexts. Integrating these sensors into microfluidic devices enables the precise quantification and analysis of small sample volumes in microscale channels. In this Perspective, we present recent advancements in the integration of diamond quantum sensors with microfluidic devices and explore their prospects with a focus on forthcoming technological developments. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry Acta Medica Okayama 2041-6520 14 42 2023 An emissive charge-transfer excited-state at the well-defined hetero-nanostructure interface of an organic conjugated molecule and two-dimensional inorganic nanosheet 11914 11923 EN Tomokazu Umeyama Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo Daizu Mizutani Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Yuki Ikeda Department of Molecular Engineering, Graduate School of Engineering, Kyoto University W. Ryan Osterloh Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Futa Yamamoto Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo Kosaku Kato Graduate School of Natural Science and Technology, Okayama University Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Masahiro Higashi Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Takumi Urakami Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Hirofumi Sato Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Hiroshi Imahori Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Precise engineering of excited-state interactions between an organic conjugated molecule and a two-dimensional semiconducting inorganic nanosheet, specifically the manipulation of charge-transfer excited (CTE) states, still remains a challenge for state-of-the-art photochemistry. Herein, we report a long-lived, highly emissive CTE state at structurally well-defined hetero-nanostructure interfaces of photoactive pyrene and two-dimensional MoS2 nanosheets via an N-benzylsuccinimide bridge (Py-Bn-MoS2). Spectroscopic measurements reveal that no charge-transfer state is formed in the ground state, but the locally-excited (LE) state of pyrene in Py-Bn-MoS2 efficiently generates an unusual emissive CTE state. Theoretical studies elucidate the interaction of MoS2 vacant orbitals with the pyrene LE state to form a CTE state that shows a distinct solvent dependence of the emission energy. This is the first example of organic-inorganic 2D hetero-nanostructures displaying mixed luminescence properties by an accurate design of the bridge structure, and therefore represents an important step in their applications for energy conversion and optoelectronic devices and sensors. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2694-2453 3 5 2023 Highly Stretchable Stress-Strain Sensor from Elastomer Nanocomposites with Movable Cross-links and Ketjenblack 394 405 EN Ryohei Ikura Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Kota Kajimoto Department of Macromolecular Science, Graduate School of Science, Osaka University Junsu Park Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Shunsuke Murayama Graduate School of Organic Materials Engineering, Yamagata University Yusei Fujiwara Department of Mechanical Engineering, Osaka Institute of Technology Motofumi Osaki Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Tomohiro Suzuki Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Hidenori Shirakawa Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Yujiro Kitamura Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Hiroaki Takahashi Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Yasumasa Ohashi Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Seiji Obata Research Core for Interdisciplinary Sciences, Okayama University Akira Harada SANKEN (The Institute of Scientific and Industrial Research), Osaka University Yuka Ikemoto Japan Synchrotron Radiation Research Institute Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Yasutomo Uetsuji Department of Mechanical Engineering, Osaka Institute of Technology Go Matsuba Graduate School of Organic Materials Engineering, Yamagata University Yoshinori Takashima Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Practical applications like very thin stress-strain sensors require high strength, stretchability, and conductivity, simultaneously. One of the approaches is improving the toughness of the stress-strain sensing materials. Polymeric materials with movable cross-links in which the polymer chain penetrates the cavity of cyclodextrin (CD) demonstrate enhanced strength and stretchability, simultaneously. We designed two approaches that utilize elastomer nanocomposites with movable cross-links and carbon filler (ketjenblack, KB). One approach is mixing SC (a single movable cross-network material), a linear polymer (poly(ethyl acrylate), PEA), and KB to obtain their composite. The electrical resistance increases proportionally with tensile strain, leading to the application of this composite as a stress- strain sensor. The responses of this material are stable for over 100 loading and unloading cycles. The other approach is a composite made with KB and a movable cross-network elastomer for knitting dissimilar polymers (KP), where movable cross-links connect the CD-modified polystyrene (PSCD) and PEA. The obtained composite acts as a highly sensitive stress-strain sensor that exhibits an exponential increase in resistance with increasing tensile strain due to the polymer dethreading from the CD rings. The designed preparations of highly repeatable or highly responsive stress-strain sensors with good mechanical properties can help broaden their application in electrical devices. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 23 14 2023 An Interface Setup Optimization Method Using a Throughput Estimation Model for Concurrently Communicating Access Points in a Wireless Local Area Network 6367 EN Fatema Akhter Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Ei Ei Htet Graduate School of Natural Science and Technology, Okayama University Bin Wu Graduate School of Natural Science and Technology, Okayama University Dezheng Kong Graduate School of Natural Science and Technology, Okayama University Shihao Fang Graduate School of Natural Science and Technology, Okayama University The IEEE 802.11 wireless local-area network (WLAN) has been deployed around the globe as a major Internet access medium due to its low cost and high flexibility and capacity. Unfortunately, dense wireless networks can suffer from poor performance due to high levels of radio interference resulting from adjoining access points (APs). To address this problem, we studied the AP transmission power optimization method, which selects the maximum or minimum power supplied to each AP so that the average signal-to-interference ratio (SIR) among the concurrently communicating APs is maximized.However, this method requires measurements of receiving signal strength (RSS) under all the possible combinations of powers. It may need intolerable loads and time as the number of APs increases. It also only considers the use of channel bonding (CB), although non-CB sometimes achieves higher performance under high levels of interference. In this paper, we present an AP interface setup optimization method using the throughput estimation model for concurrently communicating APs. The proposed method selects CB or non-CB in addition to the maximum or minimum power for each AP. This model approach avoids expensive costs of RSS measurements under a number of combinations. To estimate the RSS at an AP from another AP or a host, the model needs the distance and the obstacles between them, such as walls. Then, by calculating the estimated RSS with the model and calculating the SIR from them, the AP interface setups for a lot of APs in a large-scale wireless network can be optimized on a computer in a very short time. For evaluation, we conducted extensive experiments using Raspberry Pi for APs and Linux PCs for hosts under 12 network topologies in three buildings at Okayama University, Japan, and Jatiya Kabi Kazi Nazrul Islam University, Bangladesh. The results confirm that the proposed method selects the best AP interface setup with the highest total throughput in any topology. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0924-4247 361 2023 A soft rotary actuator with a flexible shaft using flexible pneumatic actuators 114603 EN So Shimooka Faculty of Natural Science and Technology, Okayama University Miku Kawanaka Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Akio Gofuku Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University This paper proposes a soft rotary actuator that can rotate even when its shaft is bent. The tested rotary actuator consists of three Extension-type Flexible Pneumatic Actuators (EFPA), flexible plates for restraining the EFPAs geometrically, and a polyurethane tube as a shaft. The EFPA consists of a silicone rubber tube covered with a sleeve that can expand significantly in the axial direction when the tube is pressurized. By restraining the EFPA to a helical shape using plates, the proposed rotary actuator can rotate when the three EFPAs are extended in the rotational direction upon the application of pressure. It is confirmed that the tested actuator could rotate even if the shaft is bent, because the shaft and EFPAs consist of flexible materials. The maximum rotation angle and torque are approximately 400° and 0.5 Nm, respectively, for an input pressure of 500 kPa. An analytical model of the tested actuator is proposed to predict the relationship between the rotation angle and the input pressure. A comparison between the calculated and experimental rotation angles reveals that the experimental results can be accurately predicted using the proposed analytical model, which considers the effects of EFPA friction and restraining. 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 Trial of Sportswear Type ECG Sensor Device for Cardiac Safety Management during Marathon Running 151 161 EN Takahiro Yamane Department of Biomedical Informatics, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazuya Hirano Department of Biomedical Informatics, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kenta Hirai Department of Pediatrics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Daiki Ousaka Department of Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Noriko Sakano Department of Cardiovascular Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Mizuki Morita Department of Biomedical Informatics, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Susumu Oozawa Department of Clinical Safety, Okayama University Hospital Shingo Kasahara Department of Cardiovascular Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Cardiac arrest has been reported during participation in several sports. Of these sports, marathon running is a particularly popular sport but imposes high cardiac load. Indeed, its popularity has been growing worldwide. Risk of cardiac arrest during marathon races is also expected to increase. Several studies have recorded electrocardiographic (ECG) information during marathon races to protect athletes from cardiac arrest. Although evaluable ECG data have been obtained and analyzed, cost-effectiveness of the system, data quality, and clinical significance remain inadequate. This report is the first to describe an economical electrocardiograph built into a T-shirt for use during marathon race. Twenty healthy runners aged 20 to 59 years (mean 36 years) wore the ECG device while running. The ECG data were monitored and analyzed to assess the observed frequencies of specified arrhythmias and the sections of the marathon in which the arrhythmias occurred. Of the ECG data obtained from 14 runners who completed the full marathon, six ECG datasets were evaluable. In some runners, there was inadequate contact between the electrode and body surface or poor Bluetooth connection between the ECG wireless transmitter and smartphone. Regarding arrhythmia analysis, all evaluable data that were analyzed showed some rhythm fluctuations. In conclusion, this economical T-shirt type ECG sensor provided evaluable ECG data during marathon races, although the evaluable rate was not high. The data were used to analyze specified arrhythmias, but some difficulties were encountered. The ECG sensor did not function properly because of a system error. The ECG sensor was not adequately moistened to record ECGs accurately. Moreover, some runners chose an unsuitable shirt size, which impaired the stability and strength of the electrode–skin contact. These shortcomings produced noise in the ECG data, which made it difficult to analyze arrhythmias. The next step will be to solve these problems and acquire data from a large number of runners. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0924-4247 360 2023 Fabrication and characterization of a submillimeter-scale ultrasonic motor 114524 EN Kohei Kikuchi Okayama University Mudassir Hussain Okayama University Tomoaki Mashimo Okayama University Submillimeter-scale electrically driven micromotors have the potential to revolutionize micro-robotic systems, but difficulties in their fabrication processes and unknown physical phenomena prevent their development. In this paper, we propose a submillimeter-scale rotary piezoelectric ultrasonic motor with the smallest stator (0.41 mm × 0.41 mm × 0.25 mm) reported to date. The micromachining technologies enable the creation of tiny components. A micromanipulator that can control a small amount of adhesive of sub-milligram order engenders success in manufacture of the stator. Several experiments clarify the submillimeter-scale physical behaviors, such as the admittance and the quality factor. With appropriate piezoelectric materials, submillimeter-scale ultrasonic motors are built and characterized using a rotor with 0.15 mm diameter. The motor with typical hard PZTs demonstrated maximum torque of 5.4 nNm and a maximum angular velocity of 714 rad/s at an applied voltage with amplitude of 44.8 Vp-p. Furthermore, another motor with single-crystal PMN-PT piezoelectric elements presented the possibility of low-voltage actuation. These submillimeter-scale ultrasonic motors were compared with existing comparable-size micromotors. No potential conflict of interest relevant to this article was reported.

MYU K.K. Acta Medica Okayama 0914-4935 34 8 2022 A Method for Estimating Physician Stress Using Wearable Sensor Devices 2955 2971 EN Issei Imura Graduate School of Natural Science and Technology, Okayama University Yusuke Gotoh Faculty of Natural Science and Technology, Okayama University Koji Sakai Department of Radiology, Kyoto Prefectural University of Medicine Yu Ohara Department of Radiology, Kyoto Prefectural University of Medicine Jun Tazoe Department of Radiology, Kyoto Prefectural University of Medicine Hiroshi Miura Department of Radiology, Kyoto Prefectural University of Medicine Tatsuya Hirota Department of Radiology, Kyoto Prefectural University of Medicine Akira Uchiyama Graduate School of Information Science and Technology, Osaka University Yoshinari Nomura Faculty of Natural Science and Technology, Okayama University The idea of Society 5.0 initiative has been proposed to solve various social problems by connecting virtual cyberspace and real physical space through information technology. When applying the idea to improve the work-life balance of physicians in the medical field, we must consider the increased stress owing to their long continuous working hours. Estimating the stress of physicians in their daily lives by the questionnaires is insufficient, because of the difficulty of accurate their activity recalling. By using bio-metric information such as heart rate, physical activity, and sleeping information, it was expected that the daily stress state of physicians with high accuracy. In this paper, we propose a method for estimating physician stress by analyzing bio-metric information acquired by wearing a wearable sensor device. The proposed method estimates the state of stress during daily activities by acquiring data on heart rate variability (HRV) during wakefulness as well as sleep depth during rapid eye movement (REM) and non-REM sleep. Up to seven physicians wore the wearable sensor device for the maximum of eight weeks and the sleep depth and low-/high-frequency (LF/HF) components of HRV were obtained. Our observation showed that physicians' root mean square of successive differences (rMSSDs) were constantly high in their healthy state. Therefore, the decreasing of this index can be used as an indicator of fatigue and stress. In addition, by combining LF/HF components to the rMSSDs, we may estimate the stress state of physicians and find personal stressors. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2078-2489 14 6 2023 An Edge Device Framework in SEMAR IoT Application Server Platform 312 EN Yohanes Yohanie Fridelin Panduman Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Sho Ito Graduate School of Natural Science and Technology, Okayama University Radhiatul Husna Graduate School of Natural Science and Technology, Okayama University Minoru Kuribayashi Graduate School of Natural Science and Technology, Okayama University Mitsuhiro Okayasu Graduate School of Natural Science and Technology, Okayama University Junya Shimazu Graduate School of Natural Science and Technology, Okayama University Sritrusta Sukaridhoto Department of Informatic and Computer, Politeknik Elektronika Negeri Surabaya Nowadays, the Internet of Things (IoT) has become widely used at various places and for various applications. To facilitate this trend, we have developed the IoT application server platform called SEMAR (Smart Environmental Monitoring and Analytical in Real-Time), which offers standard features for collecting, displaying, and analyzing sensor data. An edge device is usually installed to connect sensors with the server, where the interface configuration, the data processing, the communication protocol, and the transmission interval need to be defined by the user. In this paper, we proposed an edge device framework for SEMAR to remotely optimize the edge device utilization with three phases. In the initialization phase, it automatically downloads the configuration file to the device through HTTP communications. In the service phase, it converts data from various sensors into the standard data format and sends it to the server periodically. In the update phase, it remotely updates the configuration through MQTT communications. For evaluations, we applied the proposal to the fingerprint-based indoor localization system (FILS15.4) and the data logging system. The results confirm the effectiveness in utilizing SEMAR to develop IoT application systems. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers Acta Medica Okayama 2169-3536 11 2023 Stargazer: Long-Term and Multiregional Measurement of Timing/ Geolocation-Based Cloaking 52750 52762 EN Shota Fujii Graduate School of Natural Science and Technology, Okayama University Takayuki Sato Research and Development Group, Hitachi Ltd. Sho Aoki Research and Development Group, Hitachi Ltd. Yu Tsuda National Institute of Information and Communications Technology Nobutaka Kawaguchi Research and Development Group, Hitachi Ltd. Tomohiro Shigemoto Research and Development Group, Hitachi Ltd. Masato Terada Research and Development Group, Hitachi Ltd. Malicious hosts have come to play a significant and varied role in today's cyber attacks. Some of these hosts are equipped with a technique called cloaking, which discriminates between access from potential victims and others and then returns malicious content only to potential victims. This is a serious threat because it can evade detection by security vendors and researchers and cause serious damage. As such, cloaking is being extensively investigated, especially for phishing sites. We are currently engaged in a long-term cloaking study of a broader range of threats. In the present study, we implemented Stargazer, which actively monitors malicious hosts and detects geographic and temporal cloaking, and collected 30,359,410 observations between November 2019 and February 2022 for 18,397 targets from 13 sites where our sensors are installed. Our analysis confirmed that cloaking techniques are widely abused, i.e., not only in the context of specific threats such as phishing. This includes geographic and time-based cloaking, which is difficult to detect with single-site or one-shot observations. Furthermore, we found that malicious hosts that perform cloaking include those that survive for relatively long periods of time, and those whose contents are not present in VirusTotal. This suggests that it is not easy to observe and analyze the cloaking malicious hosts with existing technologies. The results of this study have deepened our understanding of various types of cloaking, including geographic and temporal ones, and will help in the development of future cloaking detection methods. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2023 Motion planning of a snake robot in crowded pipe environments EN Yongdong WANG Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University No potential conflict of interest relevant to this article was reported.

Frontiers Media Acta Medica Okayama 2296-9144 10 2023 Parameter search of a CPG network using a genetic algorithm for a snake robot with tactile sensors moving on a soft floor 1138019 EN Hajime Tamura Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tetsushi Kamegawa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University When a snake robot explores a collapsed house as a rescue robot, it needs to move through various obstacles, some of which may be made of soft materials, such as mattresses. In this study, we call mattress-like environment as a soft floor, which deforms when some force is added to it. We focused on the central pattern generator (CPG) network as a control for the snake robot to propel itself on the soft floor and constructed a CPG network that feeds back contact information between the robot and the floor. A genetic algorithm was used to determine the parameters of the CPG network suitable for the soft floor. To verify the obtained parameters, comparative simulations were conducted using the parameters obtained for the soft and hard floor, and the parameters were confirmed to be appropriate for each environment. By observing the difference in snake robot's propulsion depending on the presence or absence of the tactile sensor feedback signal, we confirmed the effectiveness of the tactile sensor considered in the parameter search. No potential conflict of interest relevant to this article was reported.

Taylor and Francis Acta Medica Okayama 1468-6996 24 1 2023 Electrochemical control of bone microstructure on electroactive surfaces for modulation of stem cells and bone tissue engineering 2183710 EN Danfeng Cao Sensor and Actuator Systems, Department of Physics, Chemistry and Biology (IFM), Linköping University Jose G. Martinez Sensor and Actuator Systems, Department of Physics, Chemistry and Biology (IFM), Linköping University Risa Anada Advanced Research Center for Oral and Craniofacial Sciences Dental School, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Emilio Satoshi Hara Advanced Research Center for Oral and Craniofacial Sciences Dental School, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hiroshi Kamioka Department of Orthodontics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Edwin W. H. Jager Sensor and Actuator Systems, Department of Physics, Chemistry and Biology (IFM), Linköping University Controlling stem cell behavior at the material interface is crucial for the development of novel technologies in stem cell biology and regenerative medicine. The composition and presentation of bio-factors on a surface strongly influence the activity of stem cells. Herein, we designed an electroactive surface that mimics the initial process of trabecular bone formation, by immobilizing chondrocyte-derived plasma membrane nanofragments (PMNFs) on its surface for rapid mineralization within 2 days. Moreover, the electroactive surface was based on the conducting polymer polypyrrole (PPy), which enabled dynamic control of the presentation of PMNFs on the surface via electrochemical redox switching, further resulting in the formation of bone minerals with different morphologies. Furthermore, bone minerals with contrasting surface morphologies had differential effects on the differentiation of human bone marrow-derived stem cells (hBMSCs) cultured on the surface. Together, this electroactive surface showed multifunctional characteristics, not only allowing dynamic control of PMNF presentation but also promoting the formation of bone minerals with different morphologies within 2 days. This electroactive substrate could be valuable for more precise control of stem cell growth and differentiation, and further development of more suitable microenvironments containing bone apatite for housing a bone marrow stem cell niche, such as biochips/bone-on-chips. No potential conflict of interest relevant to this article was reported.

ROYAL SOC CHEMISTRY Acta Medica Okayama 2046-2069 13 8 2023 Convergent evolution of animal and microbial rhodopsins 5367 5381 EN Keiichi Kojima Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuki Sudo Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Rhodopsins, a family of photoreceptive membrane proteins, contain retinal as a chromophore and were firstly identified as reddish pigments from frog retina in 1876. Since then, rhodopsin-like proteins have been identified mainly from animal eyes. In 1971, a rhodopsin-like pigment was discovered from the archaeon Halobacterium salinarum and named bacteriorhodopsin. While it was believed that rhodopsin- and bacteriorhodopsin-like proteins were expressed only in animal eyes and archaea, respectively, before the 1990s, a variety of rhodopsin-like proteins (called animal rhodopsins or opsins) and bacteriorhodopsin-like proteins (called microbial rhodopsins) have been progressively identified from various tissues of animals and microorganisms, respectively. Here, we comprehensively introduce the research conducted on animal and microbial rhodopsins. Recent analysis has revealed that the two rhodopsin families have common molecular properties, such as the protein structure (i.e., 7-transmembrane structure), retinal structure (i.e., binding ability to cis- and trans-retinal), color sensitivity (i.e., UV- and visible-light sensitivities), and photoreaction (i.e., triggering structural changes by light and heat), more than what was expected at the early stages of rhodopsin research. Contrastingly, their molecular functions are distinctively different (e.g., G protein-coupled receptors and photoisomerases for animal rhodopsins and ion transporters and phototaxis sensors for microbial rhodopsins). Therefore, based on their similarities and dissimilarities, we propose that animal and microbial rhodopsins have convergently evolved from their distinctive origins as multi-colored retinal-binding membrane proteins whose activities are regulated by light and heat but independently evolved for different molecular and physiological functions in the cognate organism. 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.

MDPI Acta Medica Okayama 1424-8220 22 22 2022 Realization of Crowded Pipes Climbing Locomotion of Snake Robot Using Hybrid Force-Position Control Method 9016 EN Yongdong Wang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tetsushi Kamegawa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University The movement capabilities of snake robots allow them to be applied in a variety of applications. We realized a snake robot climbing in crowded pipes. In this paper, we implement a sinusoidal curve control method that allows the snake robot to move faster. The control method is composed of a hybrid force-position controller that allows the snake robot to move more stably. We conducted experiments to confirm the effectiveness of the proposed method. The experimental results show that the proposed method is stable and effective compared to the previous control method that we had implemented in the snake robot. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 22 22 2022 A Throughput Request Satisfaction Method for Concurrently Communicating Multiple Hosts in Wireless Local Area Network 8823 EN Md Mahbubur Rahman Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Kwenga Ismael Munene Graduate School of Natural Science and Technology, Okayama University Sujan Chandra Roy Graduate School of Natural Science and Technology, Okayama University Minoru Kuribayashi Graduate School of Natural Science and Technology, Okayama University Melki Mario Gulo Department of Informatics and Computer Engineering, Politeknik Elektronika Negeri Surabaya Wen-Chung Kao Department of Electrical Engineering, National Taiwan Normal University Nowadays, the IEEE 802.11 wireless local area network (WLAN) has been widely used for Internet access services around the world. Then, the unfairness or insufficiency in meeting the throughput request can appear among concurrently communicating hosts with the same access point (AP), which should be solved by sacrificing advantageous hosts. Previously, we studied the fairness control method by adopting packet transmission delay at the AP. However, it suffers from slow convergence and may not satisfy different throughput requests among hosts. In this paper, we propose a throughput request satisfaction method for providing fair or different throughput requests when multiple hosts are concurrently communicating with a single AP. To meet the throughput request, the method (1) measures the single and concurrent throughput for each host, (2) calculates the channel occupying time from them, (3) derives the target throughput to achieve the given throughput request, and (4) controls the traffic by applying traffic shaping at the AP. For evaluations, we implemented the proposal in the WLAN testbed system with one Raspberry Pi AP and up to five hosts, and conducted extensive experiments in five scenarios with different throughput requests. The results confirmed the effectiveness of our proposal. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 76 6 2022 Graphene Oxide-based Endodontic Sealer: An in Vitro Study 715 721 EN Mohammed Zahedul Islam Nizami Department of Pathophysiology – Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Melahat Gorduysus Department of Pathophysiology – Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuki Shinoda-Ito Department of Pathophysiology – Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadashi Yamamoto Department of Pathophysiology – Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Shogo Takashiba Research Core for Interdisciplinary Sciences, Okayama University Zulema Arias Department of Pathophysiology – Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Original Article 10.18926/AMO/64122 The failure of endodontic treatment is directly associated with microbial infection in the root canal or periapical areas. An endodontic sealer that is both bactericidal and biocompatible is essential for the success of root canal treatments. This is one of the vital issues yet to be solved in clinical dental practice. This in vitro study assessed the effectiveness of graphene oxide (GO) composites GO-CaF2 and GO-Ag-CaF2 as endodontic sealer materials. Dentin slices were coated with either the GO-based composites or commonly used root canal sealers (non-eugenol zinc oxide sealer). The coated slices were treated in 0.9% NaCl, phosphate-buffered saline (PBS), and simulated body fluid (SBF) at 37˚C for 24 hours to compare their sealing effect on the dentin surface. In addition, the radiopacity of these composites was examined to assess whether they complied with the requirements of a sealer for good radiographic visualization. Scanning electron microscopy showed the significant sealing capability of the composites as coating materials. Radiographic images confirmed their radiopacity. Mineral deposition indicated their bioactivity, especially of GO-Ag-CaF2, and thus it is potential for regenerative application. They were both previously shown to be bactericidal to oral microbes and cytocompatible with host cells. With such a unique assemblage of critical properties, these GO-based composites show promise as endodontic sealers for protection against reinfection in root canal treatment and enhanced success in endodontic treatment overall. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 76 6 2022 Intraoperative Hypothermia Is Not Associated with Surgical Site Infections after Total Hip or Knee Arthroplasty 651 660 EN Bright Osman Abugri Department of Anesthesiology and Resuscitology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takashi Matsusaki Department of Anesthesiology and Resuscitology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Wanxu Ren Department of Anesthesiology and Resuscitology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Morimatsu Department of Anesthesiology and Resuscitology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/64115 Maintaining perioperative normothermia decreases the post-surgery surgical site infection (SSI) rate. We investigated whether SSI is associated with intraoperative hypothermia in total hip (THA) and total knee (TKA) arthroplasties by retrospectively analyzing 297 THA and TKA cases. The patients’ intraoperative core body temperature (BT) was measured by bladder catheter or forehead sensor. We evaluated the associations between SSI and intraoperative BT and other variables and patient characteristics. Fifty-six patients (18.8%) had hypothermia (BT <36°C); 43 developed SSI (14.5%); only five had hypothermia (11.6%). Intraoperative hypothermia and SSI were not significantly associated. The SSI group had more men (34.9% vs. 18.1%) and THA patients (77.4%), a longer mean surgical duration (174.3 vs. 143.5 mins), and a higher average BT (36.4°C vs. 36.2°C) than the no-SSI group. The SSI patients had a higher intraoperative BT. A multivariable analysis revealed that SSI was associated with male sex (OR 2.3, 95%CI: 1.031-4.921, p=0.042), longer surgery (OR, 1.01, 95%CI: 1.003-1.017, p=0.004), THA (OR 3.6, 95%CI: 1.258-10.085, p=0.017), and intraoperative BT >36.0°C (OR 3.6, 95%CI: 1.367-9.475, p=0.009). Intraoperative hypothermia was not associated with SSI in adults who underwent THA or TKA. These results suggest that hypothermia might not be the problem for SSI. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2542-6605 20 2022 A throughput drop estimation model and its application to joint optimization of transmission power, frequency channel, and channel bonding in IEEE 802.11n WLAN for large-scale IoT environments 100583 EN Kwenga Ismael Munene Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Md. Mahbubur Rahman Graduate School of Natural Science and Technology, Okayama University Hendy Briantoro Graduate School of Natural Science and Technology, Okayama University Sujan Chandra Roy Graduate School of Natural Science and Technology, Okayama University Minoru Kuribayashi Graduate School of Natural Science and Technology, Okayama University The concept of Internet of Things (IoT) has been widely studied in smart home networks, smart city networks, smart grid systems, autonomous driving systems, and smart healthcare systems. In IoT, the IEEE 802.11n wireless local-area network (WLAN) is used as a common communication technology due to its exibility and low cost. Then, the high performance WLAN is required to enhance quality of service (QoS) of large-scale IoT applications connecting a number of devices or sensors allocated in wide areas. WLAN can use the limited number of partially overlapping channels (POCs) at 2.4 GHz band. The WLAN performance can be degraded by interfered signals from other WLANs. Then, to optimize the POC assignment by reducing interferences, we have proposed the throughput drop estimation model for concurrently communicating multiple links under interferences. Unfortunately, the 40 MHz channel bonding (CB) and the 20 MHz non-CB are considered separately, while the transmission power is always fixed to the maximum. In this paper, we study the throughput drop estimation model under coexistence of CB and non-CB while the transmission power is changed. Then, we present its application to the joint optimization of assigning the transmission power, the frequency channel, and the channel bonding to enhance the throughput performance of IEEE 802.11n WLAN. For evaluations, we compare estimated throughputs by the model with measured ones in various network topologies to verify the model accuracy. Then, we apply the model to the joint assignment optimization in them, and confirm the effectiveness through simulations and experiments using the testbed system. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 22 17 2022 Design and Implementation of SEMAR IoT Server Platform with Applications 6436 EN Yohanes Yohanie Fridelin Panduman Graduate School of Natural Science and Technology, Okayama University Nobuo Funabiki Graduate School of Natural Science and Technology, Okayama University Pradini Puspitaningayu Graduate School of Natural Science and Technology, Okayama University Minoru Kuribayashi Graduate School of Natural Science and Technology, Okayama University Sritrusta Sukaridhoto Department of Informatic and Computer, Politeknik Elektronika Negeri Surabaya Wen-Chung Kao Department of Electrical Engineering, National Taiwan Normal University Nowadays, rapid developments of Internet of Things (IoT) technologies have increased possibilities of realizing smart cities where collaborations and integrations of various IoT application systems are essential. However, IoT application systems have often been designed and deployed independently without considering the standards of devices, logics, and data communications. In this paper, we present the design and implementation of the IoT server platform called Smart Environmental Monitoring and Analytical in Real-Time (SEMAR) for integrating IoT application systems using standards. SEMAR offers Big Data environments with built-in functions for data aggregations, synchronizations, and classifications with machine learning. Moreover, plug-in functions can be easily implemented. Data from devices for different sensors can be accepted directly and through network connections, which will be used in real-time for user interfaces, text files, and access to other systems through Representational State Transfer Application Programming Interface (REST API) services. For evaluations of SEMAR, we implemented the platform and integrated five IoT application systems, namely, the air-conditioning guidance system, the fingerprint-based indoor localization system, the water quality monitoring system, the environment monitoring system, and the air quality monitoring system. When compared with existing research on IoT platforms, the proposed SEMAR IoT application server platform offers higher flexibility and interoperability with the functions for IoT device managements, data communications, decision making, synchronizations, and filters that can be easily integrated with external programs or IoT applications without changing the codes. The results confirm the effectiveness and efficiency of the proposal. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 76 4 2022 Therapeutic Approaches Targeting miRNA in Systemic Lupus Erythematosus 359 371 EN Sumie Hiramatsu-Asano 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 Review 10.18926/AMO/63887 Systemic lupus erythematosus (SLE) is a potentially fatal systemic autoimmune disease, and its etiology involves both genetic and environmental factors such as sex hormone imbalance, genetic predisposition, epigenetic regulation, and immunological factors. Dysregulation of microRNA (miRNA) is suggested to be one of the epigenetic factors in SLE. miRNA is a 22-nucleotide single-stranded noncoding RNA that contributes to post-transcriptional modulation of gene expression. miRNA targeting therapy has been suggested to be useful for the treatment of cancers and other diseases. Gene knockout and miRNA targeting therapy have been demonstrated to improve SLE disease activity in mice. However, these approaches have not yet reached the level of clinical application. miRNA targeting therapy is limited by the fact that each miRNA has multiple targets. In addition, the expression of certain miRNAs may differ among cell tissues within a single SLE patient. This limitation can be overcome by targeted delivery and chemical modifications. In the future, further research into miRNA chemical modifications and delivery systems will help us develop novel therapeutic agents for SLE. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 22 14 2022 A Heartbeat Classifier for Continuous Prediction Using a Wearable Device 5080 EN Eko Sakti Pramukantoro Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Akio Gofuku Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Heartbeat monitoring may play an essential role in the early detection of cardiovascular disease. When using a traditional monitoring system, an abnormal heartbeat may not appear during a recording in a healthcare facility due to the limited time. Thus, continuous and long-term monitoring is needed. Moreover, the conventional equipment may not be portable and cannot be used at arbitrary times and locations. A wearable sensor device such as Polar H10 offers the same capability as an alternative. It has gold-standard heartbeat recording and communication ability but still lacks analytical processing of the recorded data. An automatic heartbeat classification system can play as an analyzer and is still an open problem in the development stage. This paper proposes a heartbeat classifier based on RR interval data for real-time and continuous heartbeat monitoring using the Polar H10 wearable device. Several machine learning and deep learning methods were used to train the classifier. In the training process, we also compare intra-patient and inter-patient paradigms on the original and oversampling datasets to achieve higher classification accuracy and the fastest computation speed. As a result, with a constrain in RR interval data as the feature, the random forest-based classifier implemented in the system achieved up to 99.67% for accuracy, precision, recall, and F1-score. We are also conducting experiments involving healthy people to evaluate the classifier in a real-time monitoring system. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 22 13 2022 A Business-to-Business Collaboration System That Promotes Data Utilization While Encrypting Information on the Blockchain 4909 EN Hiroaki Nasu Graduate School of Natural Science and Technology, Okayama University Yuta Kodera Faculty of Natural Science and Technology, Okayama University Yasuyuki Nogami Faculty of Natural Science and Technology, Okayama University Ensuring the reliability of data gathering from every connected device is an essential issue for promoting the advancement of the next paradigm shift, i.e., Industry 4.0. Blockchain technology is becoming recognized as an advanced tool. However, data collaboration using blockchain has not progressed sufficiently among companies in the industrial supply chain (SC) that handle sensitive data, such as those related to product quality, etc. There are two reasons why data utilization is not sufficiently advanced in the industrial SC. The first is that manufacturing information is top secret. Blockchain mechanisms, such as Bitcoin, which uses PKI, require plaintext to be shared between companies to verify the identity of the company that sent the data. Another is that the merits of data collaboration between companies have not been materialized. To solve these problems, this paper proposes a business-to-business collaboration system using homomorphic encryption and blockchain techniques. Using the proposed system, each company can exchange encrypted confidential information and utilize the data for its own business. In a trial, an equipment manufacturer was able to identify the quality change caused by a decrease in equipment performance as a cryptographic value from blockchain and to identify the change one month earlier without knowing the quality value. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2379-3694 7 4 2022 Dip-and-Read, Organic Solvent-Compatible, Paper-Based Analytical Devices Equipped with Chromatographic Separation for Indole Analysis in Shrimp 1194 1200 EN Sasikarn Seetasang Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Takashi Kaneta Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University We developed an organic solvent-compatible paper-based analytical device (PAD) for the quantitative analysis of indole, which is an indicator of shrimp freshness. Although indole is insoluble in water, ethyl acetate is a suitable solvent to dissolve and extract indole from shrimp. The PADs are fabricated using a cutting method that allows the use of an organic solvent because no hydrophobic barrier is needed to form fluidic channels. Ehrlich's reagent consists of 4-(dimethylamino)benzaldehyde and p-dimethylaminobenzaldehyde and was deposited onto the reaction zone of the PAD followed by lamination to prevent evaporation of the ethyl acetate. Samples are introduced into the PAD via immersion in organic sample solutions. When the PAD is immersed into an indole solution of ethyl acetate in a closed bottle, the sample solution penetrates the channel of the PAD and successively flows into the detection zone to form a hydrophilic colored product. The PADs provide a linear relationship between the logarithm of the indole concentration and the color intensity within a range of 1.0-20 ppm with correlation coefficients of r2 > 0.99. The limits of detection and quantification are 0.36 and 0.71 ppm, respectively. Relative standard deviations for both the intraday (n = 2) and interday (n = 3) precision were less than 2.5%. In the indole analysis of shrimp, the PADs separated the interfering orange-colored astaxanthin in the extract from the colored product of indole via the paper chromatographic principle. We used the PADs to investigate the degradation of shrimp, and the results showed a rapid increase in the indole level after 7 days. High-performance liquid chromatography verified the accuracy of the PADs by showing good agreement with the obtained indole levels. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 2158-3226 12 3 2022 Magnetic thickness measurement for various iron steels using magnetic sensor and effect of electromagnetic characteristics 035109 EN Keiji Tsukada 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 Shoya Adachi 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 Faculty of Environmental and Urban Engineering Department of Civil, Environmental and Applied System Engineering, Kansai University Mohd Mawardi Saari Faculty of Electrical and Electronic Engineering, Universiti Malaysia Pahang Kengo Hori Nippon Steel Metal Products Co., Ltd. Kazumasa Hisazumi Nippon Steel Corp. Tomonori Tominaga Nippon Steel Corp. The diagnosis and prevention of the deterioration of iron-steel infrastructure has become an important social issue in recent years. The thickness measurement technique (extremely low-frequency eddy current testing (ELECT)) using a magnetic sensor for detecting steel corrosion at extreme frequency ranges has been previously reported. Using the calibration curves based on the correlation between the phase of the detected magnetic signal and the plate thickness, the plate thickness reduction caused by corrosion can be estimated from the detected phase signal. Iron-steel materials have large changes in electromagnetic characteristics; therefore, the reference calibration data for each type of iron-steel are required for plate thickness estimation. In this study, the effect of electromagnetic characteristics on the magnetic thickness measurement was investigated to improve the thickness estimation. Four types of iron-steel plates (SS400, SM400A, SM490A, and SMA400AW) with thicknesses ranging from 1 mm to 18 mm were measured by ELECT, and the phase change at multiple frequencies of each plate were analyzed. The shift in the phase and linearity regions of the calibration curves for each type of steel plate was observed. To analyze this shift phenomenon, the electromagnetic characteristics (permeability mu and conductivity sigma) of each type of steel were measured. Compared with the permeability mu and conductivity sigma of each steel plate in the applied magnetic field strength range, the product (sigma mu) for various steel plates decreased in the following order: SM400 > SS400 >SMA400AW > SM490A. The product of mu and sigma is related to the skin depth, indicating the electromagnetic wave attenuation and eddy current phase shift in the material. Therefore, each shift in the calibration curve of each type of iron steel is explained by the changes in the parameters sigma and mu. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 22 9 2022 Displacement Sensing of an Active String Actuator Using a Step-Index Multimode Optical Fiber Sensor 3232 EN Weihang Tian Graduate School of Natural Science and Technology, Okayama University Shuichi Wakimoto Graduate School of Natural Science and Technology, Okayama University Takefumi Kanda Graduate School of Natural Science and Technology, Okayama University Daisuke Yamaguchi Graduate School of Natural Science and Technology, Okayama University A thin McKibben artificial muscle is a pneumatic actuator with an outer diameter of only 1.8 mm. We fabricated a string-shaped actuator called an "active string actuator," which achieves a high contractile displacement by accumulating thin McKibben artificial muscles. To control the displacement, the length of the active string actuator should be estimated. However, this is difficult because bulky and rigid sensors are unsuitable for the sensor element of the active string actuator. Therefore, in this study, we propose a new sensing method for estimating the length of an active string actuator. The proposed sensing system is simple and comprises only three components: a step-index multimode optical fiber, a light emitter, and a light receiver. A step-index multimode optical fiber was combined with the active string actuator, and the length was estimated from the change in the amount of light propagating in the optical fiber when the active string actuator was driven. Fundamental experiments were conducted in this study, and the results demonstrated that the optical fiber sensor value changed with the actuator length. This suggests that it is possible to estimate the displacement of an active string actuator using an optical fiber sensor. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 76 1 2022 Mouse Model for Optogenetic Genome Engineering 1 5 EN Tomoka Takao Department of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Daisuke Yamada Department of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takeshi Takarada Department of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Review 10.18926/AMO/63202 Optogenetics, a technology to manipulate biological phenomena thorough light, has attracted much attention in neuroscience. Recently, the Magnet System, a photo-inducible protein dimerization system which can control the intracellular behavior of various biomolecules with high accuracy using light was developed. Furthermore, photoactivation systems for controlling biological phenomena are being developed by combining this technique with genome-editing technology (CRISPR/Cas9 System) or DNA recombination technology (Cre-loxP system). Herein, we review the history of optogenetics and the latest Magnet System technology and introduce our recently developed photoactivatable Cre knock-in mice with temporal-, spatial-, and cell-specific accuracy. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 21 22 2021 Detection of Lung Cancer Cells in Solutions Using a Terahertz Chemical Microscope 7631 EN Yuichi Yoshida Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Xue Ding Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kohei Iwatsuki Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Katsuya Taniizumi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hirofumi Inoue Graduate School of Medicine Dentistry and Pharmaceutical Sciences, 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 Cancer genome analysis has recently attracted attention for personalized cancer treatment. In this treatment, evaluation of the ratio of cancer cells in a specimen tissue is essential for the precise analysis of the genome. Conventionally, the evaluation takes at least two days and depends on the skill of the pathologist. In our group, a terahertz chemical microscope (TCM) was developed to easily and quickly measure the number of cancer cells in a solution. In this study, an antibody was immobilized on a sensing plate using an avidin-biotin reaction to immobilize it for high density and to improve antibody alignment. In addition, as the detected terahertz signals vary depending on the sensitivity of the sensing plate, the sensitivity was evaluated using pH measurement. The result of the cancer cell detection was corrected using the result of pH measurement. These results indicate that a TCM is expected to be an excellent candidate for liquid biopsies in cancer diagnosis. No potential conflict of interest relevant to this article was reported.

Institute of Electronics, Information and Communications Engineers (IEICE) Acta Medica Okayama 0916-8532 E99.D 12 2016 Rule-Based Sensor Data Aggregation System for M2M Gateways 2943 2955 EN Yuichi Nakamura Hitachi, Ltd. Akira Moriguchi Hitachi Solutions, Ltd. Masanori Irie Hitachi Solutions, Ltd. Taizo Kinoshita Hitachi, Ltd. Toshihiro Yamauchi Graduate School of Natural Science and Technology at Okayama University To reduce the server load and communication costs of machine-to-machine (M2M) systems, sensor data are aggregated in M2M gateways. Aggregation logic is typically programmed in the C language and embedded into the firmware. However, developing aggregation programs is difficult for M2M service providers because it requires gatewayspecific knowledge and consideration of resource issues, especially RAM usage. In addition, modification of aggregation logic requires the application of firmware updates, which are risky. We propose a rule-based sensor data aggregation system, called the complex sensor data aggregator (CSDA), for M2M gateways. The functions comprising the data aggregation process are subdivided into the categories of filtering, statistical calculation, and concatenation. The proposed CSDA supports this aggregation process in three steps: the input, periodic data processing, and output steps. The behaviors of these steps are configured by an XML-based rule. The rule is stored in the data area of flash ROM and is updatable through the Internet without the need for a firmware update. In addition, in order to keep within the memory limit specified by the M2M gateway’s manufacturer, the number of threads and the size of the working memory are static after startup, and the size of the working memory can be adjusted by configuring the sampling setting of a buffer for sensor data input. The proposed system is evaluated in an M2M gateway experimental environment. Results show that developing CSDA configurations is much easier than using C because the configuration decreases by 10%. In addition, the performance evaluation demonstrates the proposed system’s ability to operate on M2M gateways. No potential conflict of interest relevant to this article was reported.

Nature Research Acta Medica Okayama 2045-2322 11 1 2021 Quantification of patellar tendon reflex using portable mechanomyography and electromyography devices 2284 EN Hironori Tsuji Department of Orthopaedic Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Haruo Misawa Department of Orthopaedic Surgery, Okayama University Hospital Tomoyuki Takigawa Department of Orthopaedic Surgery, Kobe Red Cross Hospital Tomoko Tetsunaga Department of Orthopaedic Surgery, Okayama University Hospital Kentaro Yamane Department of Orthopaedic Surgery, Okayama University Hospital Yoshiaki Oda Department of Orthopaedic Surgery, Okayama University Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Dentistry, and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Deep tendon reflexes are one of the main components of the clinical nervous system examinations. These assessments are inexpensive and quick. However, evaluation can be subjective and qualitative. This study aimed to objectively evaluate hyperreflexia of the patellar tendon reflex using portable mechanomyography (MMG) and electromyography (EMG) devices. This study included 10 preoperative patients (20 legs) who had a pathology that could cause bilateral patellar tendon hyperreflexia and 12 healthy volunteers (24 legs) with no prior history of neurological disorders. We attached MMG/EMG sensors onto the quadriceps and tapped the patellar tendon with maximal and constant force. Our results showed a significantly high amplitude of the root mean square (RMS) and low frequency of the mean power frequency (MPF) in the rectus femoris, vastus medialis, and vastus lateralis muscles in both EMG and MMG with both maximal and constant force. Especially in the patients with cervical and thoracic myelopathy, the receiver operating characteristic (ROC) curve for diagnosing hyperreflexia of the patellar tendon showed a moderate to very high area under the curve for all EMG-RMS, EMG-MPF, MMG-RMS, and MMG-MPF values. The use of EMG and MMG for objectively quantifying the patellar tendon reflex is simple and desirable for future clinical applications and could help diagnose neurological disorders. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 75 3 2021 Role of the Transcription Factor BTB and CNC Homology 1 in a Rat Model of Acute Liver Injury Induced by Experimental Endotoxemia 363 372 EN Nohito Tanioka Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroko Shimizu Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Emiko Omori Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toru Takahashi Faculty of Health and Welfare Science, Okayama Prefectural University Masakazu Yamaoka Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Morimatsu Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/62232 Hepatic oxidative stress plays an important role in the pathogenesis of several acute liver diseases, and free heme is thought to contribute to endotoxemia-induced acute liver injury. The heme oxygenase 1 (HO-1) gene is upregulated and the δ-aminolevulinate synthase (ALAS1) gene is downregulated in the rat liver following lipopolysaccharide (LPS) treatment. BTB and CNC homology 1 (Bach1) is a heme-responsive transcription factor that normally represses HO-1 expression. In this study, we evaluated the changes in HO-1, ALAS1, and Bach1 expression and nuclear Bach1 expression in rat livers following intravenous LPS administration (10 mg/kg body weight). LPS significantly upregulated HO-1 mRNA and downregulated ALAS1 mRNA in the rat livers, suggesting that hepatic free heme concentrations are increased after LPS treatment. Bach1 mRNA was strongly induced after LPS injection. In contrast, nuclear Bach1 was significantly but transiently decreased after LPS treatment. Rats were also administered hemin (50 mg/kg body weight) intravenously to elevate heme concentrations, which decreased nuclear Bach1 levels. Our results suggest that elevated hepatic free heme may be associated with a decline of nuclear Bach1, and induction of Bach1 mRNA may compensate for the decreased nuclear Bach1 after LPS treatment in the rat liver. No potential conflict of interest relevant to this article was reported.

岡山大学大学院ヘルスシステム統合科学研究科 Acta Medica Okayama 2436-3227 1 2021 遠隔での見守りのための機器・サービスの調査と訪問看護での利用を想定した分類 47 63 EN Toshio Sakamoto Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Akina Hirata Yell Co., Ltd. Mizuki Morita Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University 10.18926/interdisciplinary/61889 This study aims to improve the quality of home nursing care for the elderly. The report presents web-based information about devices and services for remote monitoring and health management using information and communication technology and about how they can improve home care nursing station efficiency in Japan. The search terms "elderly people," "watch over," and "service," plus "sensor" were used to narrow the search. After repeating the search using a chained search for materials and links extracted from those search results, services for home care stations particularly addressing the remote monitoring of elderly people were selected and extracted. Early detection of abnormalities for support by home health nurse responsibilities for observing the general condition of the patient was chosen as the main evaluation index of usefulness. The contractor and service cost were secondary evaluation axes. Results show 9 information communication devices and services for real-time monitoring of the elderly persons’ vital signs in real time for 24 hr, 2 of which are highly useful for early detection of abnormalities and subsequent response. Results suggest that other services might be more useful, depending on how they are used, and that general-purpose services with minimum functions and low cost of introduction and maintenance can provide more opportunities for utilization. Providing these services on a BtoBtoC model and responding to patients’ medical needs can supplement home care nursing station work, increase human resource and time efficiencies, and give patients "the feeling that a nurse is always at their bedside,” even when far away. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 25901524 5 2021 Structural basis of enzyme activity regulation by the propeptide of l-lysine α-oxidase precursor from Trichoderma viride 100044 EN Masaki Kitagawa Department of Macromolecular Science, Graduate School of Science, Osaka University Nanako Ito Department of Macromolecular Science, Graduate School of Science, Osaka University Yuya Matsumoto Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University Masaya Saito Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University Takashi Tamura Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University Hitoshi Kusakabe Enzyme Sensor Co., Ltd. Kenji Inagaki Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University Katsumi Imada Department of Macromolecular Science, Graduate School of Science, Osaka University Harmuful proteins are usually synthesized as inactive precursors and are activated by proteolytic processing. l-Amino acid oxidase (LAAO) is a flavoenzyme that catalyzes the oxidative deamination of l-amino acid to produce a 2-oxo acid with ammonia and highly toxic hydrogen peroxide and, therefore, is expressed as a precursor. The LAAO precursor shows significant variation in size and the cleavage pattern for activation. However, the molecular mechanism of how the propeptide suppresses the enzyme activity remains unclear except for deaminating/decarboxylating Pseudomonasl-phenylalanine oxidase (PAO), which has a short N-terminal propeptide composed of 14 residues. Here we show the inactivation mechanism of the l-lysine oxidase (LysOX) precursor (prLysOX), which has a long N-terminal propeptide composed of 77 residues, based on the crystal structure at 1.97 Å resolution. The propeptide of prLysOX indirectly changes the active site structure to inhibit the enzyme activity. prLysOX retains weak enzymatic activity with strict specificity for l-lysine and shows raised activity in acidic conditions. The structures of prLysOX crystals that soaked in a solution with various concentrations of l-lysine have revealed that prLysOX can adopt two conformations; one is the inhibitory form, and the other is very similar to mature LysOX. The propeptide region of the latter form is disordered, and l-lysine is bound to the latter form. These results indicate that prLysOX uses a different strategy from PAO to suppress the enzyme activity and suggest that prLysOX can be activated quickly in response to the environmental change without proteolytic processing. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0022-3042 158 2020 Phosphatidylinositol‐3 kinase mediates the sweet suppressive effect of leptin in mouse taste cells 233 245 EN Ryusuke Yoshida Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Robert F. Margolskee Monell Chemical Senses Center Yuzo Ninomiya Monell Chemical Senses Center Leptin is known to selectively suppress neural and taste cell responses to sweet compounds. The sweet suppressive effect of leptin is mediated by the leptin receptor Ob‐Rb, and the ATP‐gated K+ (KATP) channel expressed in some sweet‐sensitive, taste receptor family 1 member 3 (T1R3)‐positive taste cells. However, the intracellular transduction pathway connecting Ob‐Rb to KATP channel remains unknown. Here we report that phosphoinositide 3‐kinase (PI3K) mediates leptin's suppression of sweet responses in T1R3‐positive taste cells. In in situ taste cell recording, systemically administrated leptin suppressed taste cell responses to sucrose in T1R3‐positive taste cells. Such leptin's suppression of sucrose responses was impaired by co‐administration of PI3K inhibitors (wortmannin or LY294002). In contrast, co‐administration of signal transducer and activator of transcription 3 inhibitor (Stattic) or Src homology region 2 domain‐containing phosphatase‐2 inhibitor (SHP099) had no effect on leptin's suppression of sucrose responses, although signal transducer and activator of transcription 3 and Src homology region 2 domain‐containing phosphatase‐2 were expressed in T1R3‐positive taste cells. In peeled tongue epithelium, phosphatidylinositol (3,4,5)‐trisphosphate production and phosphorylation of AKT by leptin were immunohistochemically detected in some T1R3‐positive taste cells but not in glutamate decarboxylase 67‐positive taste cells. Leptin‐induced phosphatidylinositol (3,4,5)‐trisphosphate production was suppressed by LY294002. Thus, leptin suppresses sweet responses of T1R3‐positive taste cells by activation of Ob‐Rb–PI3K–KATP channel pathway. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 0032-0781 61 8 2020 Decoding Plant–Environment Interactions That Influence Crop Agronomic Traits 1408 1418 EN Keiichi Mochida Institute of Plant Science and Resources, Okayama University Ryuei Nishii School of Information and Data Sciences, Nagasaki University Takashi Hirayama Institute of Plant Science and Resources, Okayama University To ensure food security in the face of increasing global demand due to population growth and progressive urbanization, it will be crucial to integrate emerging technologies in multiple disciplines to accelerate overall throughput of gene discovery and crop breeding. Plant agronomic traits often appear during the plants’ later growth stages due to the cumulative effects of their lifetime interactions with the environment. Therefore, decoding plant–environment interactions by elucidating plants’ temporal physiological responses to environmental changes throughout their lifespans will facilitate the identification of genetic and environmental factors, timing and pathways that influence complex end-point agronomic traits, such as yield. Here, we discuss the expected role of the life-course approach to monitoring plant and crop health status in improving crop productivity by enhancing the understanding of plant–environment interactions. We review recent advances in analytical technologies for monitoring health status in plants based on multi-omics analyses and strategies for integrating heterogeneous datasets from multiple omics areas to identify informative factors associated with traits of interest. In addition, we showcase emerging phenomics techniques that enable the noninvasive and continuous monitoring of plant growth by various means, including three-dimensional phenotyping, plant root phenotyping, implantable/injectable sensors and affordable phenotyping devices. Finally, we present an integrated review of analytical technologies and applications for monitoring plant growth, developed across disciplines, such as plant science, data science and sensors and Internet-of-things technologies, to improve plant productivity. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 20 21 2020 Diagnosis of Occlusal Tooth Wear Using 3D Imaging of Optical Coherence Tomography Ex Vivo 6016 EN Misa Kashiwa Department of Cariology and Operative Dentistry Department, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University Yasushi Shimada Department of Operative Dentistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Alireza Sadr Department of Cariology and Operative Dentistry Department, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University Masahiro Yoshiyama Department of Operative Dentistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yasunori Sumi Center of Advanced Medicine for Dental and Oral Diseases, Department for Advanced Dental Research, National Center for Geriatrics and Gerontology Junji Tagami Department of Cariology and Operative Dentistry Department, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University The aim of this study was to assess the utility of 3D imaging of optical coherence tomography (OCT) for the diagnosis of occlusal tooth wear ex vivo. Sixty-three extracted human molars with or without visible tooth wear were collected to take digital intraoral radiography and 3D OCT images. The degree of tooth wear was evaluated by 12 examiners and scored using 4-rank scale: 1-slight enamel wear; 2-distinct enamel wear; 3-tooth wear with slight dentin exposure; 4-tooth wear with distinct involvement of dentin. The degree of tooth wear was validated by the histological view of confocal laser scanning microscopy (CLSM). The sensitivity, specificity, and area under the curve (AUC) of receiver operating characteristic analysis were calculated. Diagnostic accuracy was compared with the agreement with CLSM observation using weighted kappa. The results were statistically analyzed at a significance level of alpha = 0.05. Three-dimensional OCT showed significantly higher sensitivity (p < 0.05) for all the diagnostic thresholds of enamel wear and dentin exposure than digital radiography (0.82, 0.85, and 0.79 vs. 0.56, 0.52, and 0.57, respectively). Three-dimensional OCT showed higher AUC and kappa coefficients than digital radiography (p < 0.05), where mean AUC and Kappa values were 0.95 and 0.76 for OCT and 0.92 and 0.47 for radiography, respectively. No significant difference of specificity was observed (p > 0.05). Three-dimensional OCT could visualize and estimate the degree of tooth wear and detect the dentin exposure at the tooth wear surface accurately and reproducibly. Consequently, a new guideline for tooth wear assessment can be proposed using OCT. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-2607 8 9 2020 Regulation of Chitin-Dependent Growth and Natural Competence in Vibrio parahaemolyticus 1303 EN Anusuya Debnath Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tamaki Mizuno Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shin-Ichi Miyoshi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Vibrios can degrade chitin surfaces to soluble N-acetyl glucosamine oligosaccharides (GlcNAc(n)) that can be utilized as a carbon source and also induce a state of natural genetic competence. In this study, we characterized chitin-dependent growth and natural competence in Vibrio parahaemolyticus and its regulation. We found that growth on chitin was regulated through chitin sensors ChiS (sensor histidine kinase) and TfoS (transmembrane transcriptional regulator) by predominantly controlling the expression of chitinase VPA0055 (ChiA2) in a TfoX-dependent manner. The reduced growth of Delta chiA2, Delta chiS and Delta tfoS mutants highlighted the critical role played by ChiA2 in chitin breakdown. This growth defect of Delta chiA2 mutant could be recovered when chitin oligosaccharides GlcNAc(2) or GlcNAc(6) were supplied instead of chitin. The Delta tfoS mutant was also able to grow on GlcNAc(2) but the Delta chiS mutant could not, which indicates that GlcNAc(2) catabolic operon is dependent on ChiS and independent of TfoS. However, the Delta tfoS mutant was unable to utilize GlcNAc(6) because the periplasmic enzymes required for the breakdown of GlcNAc(6) were found to be downregulated at the mRNA level. We also showed that natural competence can be induced only by GlcNAc(6), not GlcNAc(2), because the expression of competence genes was significantly higher in the presence of GlcNAc(6) compared to GlcNAc(2). Moreover, this might be an indication that GlcNAc(2) and GlcNAc(6) were detected by different receptors. Therefore, we speculate that GlcNAc(2)-dependent activation of ChiS and GlcNAc(6)-dependent activation of TfoS might be crucial for the induction of natural competence in V. parahaemolyticus through the upregulation of the master competence regulator TfoX. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 74 5 2020 Three-dimensional Evaluation of Abnormal Gait in Patients with Hip Osteoarthritis 391 399 EN Daisuke Homma Division of Orthopedic Surgery, Niigata University Graduate School of Medical and Dental Sciences Izumi Minato Division of Orthopedic Surgery, Niigata Rinko Hospital Norio Imai Division of Comprehensive Geriatrics in Community, Niigata University Graduate School of Medical and Dental Sciences Dai Miyasaka Division of Orthopedic Surgery, Niigata Bandai Hospital Yoshinori Sakaif Division of Orthopedic Surgery, Niigata General Hospital Yoji Horigome Division of Orthopedic Surgery, Niigata University Graduate School of Medical and Dental Sciences Hayato Suzuki Division of Orthopedic Surgery, Niigata University Graduate School of Medical and Dental Sciences Hayato Shimada Division of Orthopedic Surgery, Mito Saiseikai General Hospital Yoichiro Dohmae Division of Orthopedic Surgery, Niigata Bandai Hospital Naoto Endo Division of Orthopedic Surgery, Niigata University Graduate School of Medical and Dental Sciences Original Article 10.18926/AMO/60798 Indexes for objectively evaluating abnormal gait in hip osteoarthritis (OA) patients and determining effective interventions are unclear. We analyzed the abnormal gait of hip OA patients by focusing on movements of the trunk and pelvis to establish an effective evaluation index for each direction of motion. We studied 28 patients with secondary hip OA due to developmental dysplasia of the hip and 16 controls. The trunk and pelvic movements during gait were measured in the medial-lateral (x), vertical (y), and back-and-forth (z) directions by a triaxial angular accelerometer. Gait speed, steps, step length, muscle strength, range of motion, and timed up-and-go (TUG) test performance were measured. We determined the correlations between physical function and the index of abnormal gait in the hip OA patients. Movements other than trunk and pelvic motions in the y-direction indicated abnormal gait in the patients. Significant correlations were found between abnormal gait and range of motions (extension, internal rotation), TUG score, stride length, and steps. The TUG test, stride length and steps were important for evaluating abnormal gait in hip OA patients. Individual interventions for each movement direction are required. No potential conflict of interest relevant to this article was reported.

Nature Acta Medica Okayama 2045-2322 10 1 2020 Mechanism underlying hippocampal long-term potentiation and depression based on competition between endocytosis and exocytosis of AMPA receptors 14711 EN Tomonari Sumi Research Institute for Interdisciplinary Science, Okayama University Kouji Harada Department of Computer Science and Engineering, Toyohashi University of Technology N-methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP) and long-term depression (LTD) of signal transmission form neural circuits and thus are thought to underlie learning and memory. These mechanisms are mediated by AMPA receptor (AMPAR) trafficking in postsynaptic neurons. However, the regulatory mechanism of bidirectional plasticity at excitatory synapses remains unclear. We present a network model of AMPAR trafficking for adult hippocampal pyramidal neurons, which reproduces both LTP and LTD. We show that the induction of both LTP and LTD is regulated by the competition between exocytosis and endocytosis of AMPARs, which are mediated by the calcium-sensors synaptotagmin 1/7 (Syt1/7) and protein interacting with C-kinase 1 (PICK1), respectively. Our result indicates that recycling endosomes containing AMPAR are always ready for Syt1/7-dependent exocytosis of AMPAR at peri-synaptic/synaptic membranes. This is because molecular motor myosin V-b constitutively transports the recycling endosome toward the membrane in a Ca2+-independent manner. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-2607 8 6 2020 Lanthanide-Dependent Methanol and Formaldehyde Oxidation inMethylobacterium aquaticumStrain 22A 822 EN Patcha Yanpirat Institute of Plant Science and Resources, Okayama University Yukari Nakatsuji Institute of Plant Science and Resources, Okayama University Shota Hiraga Institute of Plant Science and Resources, Okayama University Yoshiko Fujitani Institute of Plant Science and Resources, Okayama University Terumi Izumi Institute of Plant Science and Resources, Okayama University Sachiko Masuda Institute of Plant Science and Resources, Okayama University Ryoji Mitsui Department of Biochemistry, Faculty of Science, Okayama University of Science Tomoyuki Nakagawa The United Graduate School of Agricultural Science, Gifu University Akio Tani Institute of Plant Science and Resources, Okayama University Lanthanides (Ln) are an essential cofactor for XoxF-type methanol dehydrogenases (MDHs) in Gram-negative methylotrophs. The Ln(3+)dependency of XoxF has expanded knowledge and raised new questions in methylotrophy, including the differences in characteristics of XoxF-type MDHs, their regulation, and the methylotrophic metabolism including formaldehyde oxidation. In this study, we genetically identified one set of Ln(3+)- and Ca2+-dependent MDHs (XoxF1 and MxaFI), that are involved in methylotrophy, and an ExaF-type Ln(3+)-dependent ethanol dehydrogenase, among six MDH-like genes inMethylobacterium aquaticumstrain 22A. We also identified the causative mutations in MxbD, a sensor kinase necessary formxaFexpression andxoxF1repression, for suppressive phenotypes inxoxF1mutants defective in methanol growth even in the absence of Ln(3+). Furthermore, we examined the phenotypes of a series of formaldehyde oxidation-pathway mutants (fae1,fae2,mchin the tetrahydromethanopterin (H4MPT) pathway andhgdin the glutathione-dependent formaldehyde dehydrogenase (GSH) pathway). We found that MxaF produces formaldehyde to a toxic level in the absence of the formaldehyde oxidation pathways and that either XoxF1 or ExaF can oxidize formaldehyde to alleviate formaldehyde toxicity in vivo. Furthermore, the GSH pathway has a supportive role for the net formaldehyde oxidation in addition to the H4MPT pathway that has primary importance. Studies on methylotrophy inMethylobacteriumspecies have a long history, and this study provides further insights into genetic and physiological diversity and the differences in methylotrophy within the plant-colonizing methylotrophs. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry Acta Medica Okayama 1744-683X 16 6 2019 Preparation of tough, thermally stable, and water-resistant double-network ion gels consisting of silica nanoparticles/poly(ionic liquid)s through photopolymerisation of an ionic monomer and subsequent solvent removal 1572 1581 EN Takaichi Watanabe Department of Applied Chemistry, Graduate School of Natural Science, Okayama University Ruri Takahashi Department of Applied Chemistry, Graduate School of Natural Science, Okayama University Tsutomu Ono Department of Applied Chemistry, Graduate School of Natural Science, Okayama University We report the preparation of tough, thermally stable, and water-resistant double-network (DN) ion gels, which consist of a partially-clustered silica nanoparticle network and poly(ionic liquid) (PIL) network holding an ionic liquid. Silica nanoparticles/poly([Evim][Tf2N]) DN ion gels are prepared by photo-induced radical polymerisation of [Evim][Tf2N] in a mixture containing silica nanoparticles, [Bmim][Tf2N], ionic liquid based cross-linker [(VIM)2C4][Tf2N]2, and ethyl acetate, followed by subsequent solvent evaporation. Tensile strength measurements show that the mechanical properties of the PIL DN ion gels were higher than those of the PIL single-network (SN) ion gel. A rheological study indicates that an enhancement in mechanical strength of the PIL DN ion gels can be achieved when silica nanoparticles form partial clusters in [Bmim][Tf2N]. The cyclic stress–strain measurement of the PIL DN ion gels shows hysteresis loops, suggesting that the silica nanoparticle clusters rupture and dissipate the loading energy when the PIL DN ion gels undergo a large deformation. The fracture strength and Young's modulus of the PIL DN ion gels increase as the diameter of the silica nanoparticles is decreased. Thermogravimetric analysis measurement shows that the PIL DN ion gel has a high decomposition temperature of approximately 400 °C. Moreover, the swelling test shows that the PIL DN ion gel possesses an excellent water-resistant property because of the hydrophobic nature of the PIL backbone. We believe that such tough, thermally stable, and water-resistant PIL DN ion gels can be used as carbon dioxide separation membranes, sensors, and actuators for soft robotics. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 74 3 2020 Dkk3/REIC, an N-glycosylated Protein, Is a Physiological Endoplasmic Reticulum Stress Inducer in the Mouse Adrenal Gland 199 208 EN Hirofumi Fujita Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tetsuya Bando Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Seiichi Oyadomari Division of Molecular Biology, Institute for Genome Research, University of Tokushima Kazuhiko Ochiai Department of Basic Science, School of Veterinary Nursing and Technology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University Masami Watanabe Department of Urology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiromi Kumon Innovation Center Okayama for Nanobio-Targeted Therapy, Okayama University Hideyo Ohuchi Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/59950 Dickkopf 3 (Dkk3) is a secreted protein belonging to the Dkk family and encoded by the orthologous gene of REIC. Dkk3/REIC is expressed by mouse and human adrenal glands, but the understanding of its roles in this organ is still limited. To determine the functions of Dkk3 in the mouse adrenal gland, we first identified that the mouse Dkk3 protein is N-glycosylated in the adrenal gland as well as in the brain. We performed proteome analysis on adrenal glands from Dkk3-null mice, in which exons 5 and 6 of the Dkk3 gene are deleted. Twodimensional polyacrylamide gel electrophoresis of adrenal proteins from wild-type and Dkk3-null mice revealed 5 protein spots whose intensities were altered between the 2 genotypes. Mass spectrometry analysis of these spots identified binding immunoglobulin protein (BiP), an endoplasmic reticulum (ER) chaperone. To determine whether mouse Dkk3 is involved in the unfolded protein response (UPR), we carried out a reporter assay using ER-stress responsive elements. Forced expression of Dkk3 resulted in the induction of distinct levels of reporter expression, showing the UPR initiated by the ER membrane proteins of activating transcription factor 6 (ATF6) and inositol-requring enzyme 1 (IRE1). Thus, it is possible that Dkk3 is a physiological ER stressor in the mouse adrenal gland. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1424-8220 20 6 2020 Diagnosis of Occlusal Caries with Dynamic Slicing of 3D Optical Coherence Tomography Images 1659 EN Minh N. Luong Department of Restorative Dentistry, University of Washington Yasushi Shimada Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazuyuki Araki Division of Radiology, Department of Oral Diagnostic Sciences, Showa University School of Dentistry Masahiro Yoshiyama Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Junji Tagami Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University Alireza Sadr Department of Restorative Dentistry, University of Washington Detecting the extent of occlusal caries is a clinically important but challenging task required for treatment decision making. The aim of this study was to assess the diagnostic power of 3D swept-source optical coherence tomography (OCT) for evaluation of occlusal caries in comparison with X-ray radiography. Extracted human molars not exhibiting American Dental Association (ADA) criteria advanced caries were mounted in a silicone block and digital dental radiographs were captured from the buccal side. Subsequently, occlusal surfaces were scanned with a prototype Yoshida Dental OCT. Thirteen examiners evaluated the presence and extent of caries on radiographs and dynamically sliced 3D OCT video images, using a 4 level scale-0: intact; 1: enamel demineralization without cavitation; 2: enamel caries with cavitation; 3: dentin caries with or without cavitation. Sensitivity, specificity and area under operating characteristic curves (Az) were statistically analyzed (alpha = 0.05). Reliability analysis showed an excellent agreement among the 13 examiners for both methods. The OCT presented a significantly higher sensitivity and Az value for the detection of caries compared to radiographs (p < 0.05). Radiography showed especially low sensitivity for dentin caries (0-2 versus 3). Dynamic slicing of 3D OCT volumes is a powerful adjunct tool to visual inspection to diagnose the dentin occlusal caries in vitro. No potential conflict of interest relevant to this article was reported.

IOP Publishing Acta Medica Okayama 2053-1591 7 5 2020 Synthesis of solvent-free conductive and flexible cellulose-carbon nanohorn sheets and their application as a water vapor sensor 056402 EN Karthik Paneer Selvam Graduate School of Natural Science and Technology, Okayama University Tomohiro Nakagawa Graduate School of Natural Science and Technology, Okayama University Tatsuki Marui Graduate School of Natural Science and Technology, Okayama University Hirotaka Inoue Graduate School of Natural Science and Technology, Okayama University Takeshi Nishikawa Graduate School of Natural Science and Technology, Okayama University Yasuhiko Hayashi Graduate School of Natural Science and Technology, Okayama University Carbon nanohorns (CNHs) are mixed with cellulose to make freestanding thin-film conductive sheets. CNHs, at different ratios (5, 10, 25, 50 wt%), form composites with cellulose (hydroxyethylcellulose). Freestanding cellulose-carbon nanohorn (CCN) sheets were fabricated using a 100 mu m-thick metal bar coater. Surfactants or any other chemical treatments to tailor the surface properties of CNHs were avoided to obtain composite sheets from pristine CNHs and cellulose. Utilizing the hygroscopic property of hydroxyethylcellulose and the electrical conductivity of CNHs paved a path to perform this experiment. The synthesis technique is simple, and the fabrication and drying of the sheets were effortless. As the loading concentration of CNH increased, the resistance, flexibility, and strength of the CCN composite sheets decreased. The maximum loading concentration possible to obtain a freestanding CCN sheet is 50 wt%. The resistance of the maximum loading concentration of CNH was 53 k omega. The response of the CCN sheets to water vapor was 4 s and recover time was 13 s, and it is feasible to obtain a response for different concentrations of water vapor. High-resolution transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, resistance measurement, tensile strength measurement, and thermogravimetric analysis were used to investigate the mechanical, morphological, electrical, and chemical properties of the CCN sheets. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 19365233 13 4 2020 S100 Soil Sensor Receptors and Molecular Targeting Therapy Against Them in Cancer Metastasis 100753 EN Nahoko Tomonobu Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Rie Kinoshita Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masakiyo Sakaguchi Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences The molecular mechanisms underlying the 'seed and soil' theory are unknown. S100A8/A9 (a heterodimer complex of S100A8 and S100A9 proteins that exhibits a 'soil signal') is a ligand for Toll-like receptor 4, causing distant melanoma cells to approach the lung as a 'seeding' site. Unknown soil sensors for S100A8/A9 may exist, e.g., extracellular matrix metalloproteinase inducer, neuroplastin, activated leukocyte cell adhesion molecule, and melanoma cell adhesion molecule. We call these receptor proteins 'novel S100 soil sensor receptors (novel SSSRs).' Here we review and summarize a crucial role of the S100A8/A9-novel SSSRs' axis in cancer metastasis. The binding of S100A8/A9 to individual SSSRs is important in cancer metastasis via upregulations of the epithelial-mesenchymal transition, cellular motility, and cancer cell invasiveness, plus the formation of an inflammatory immune suppressive environment in metastatic organ(s). These metastatic cellular events are caused by the SSSR-featured signal transductions we identified that provide cancer cells a driving force for metastasis. To deprive cancer cells of these metastatic forces, we developed novel biologics that prevent the interaction of S100A8/A9 with SSSRs, followed by the efficient suppression of S100A8/A9-mediated lung-tropic metastasis in vivo. No potential conflict of interest relevant to this article was reported.

Academic Press Acta Medica Okayama 0006291X 524 4 2020 S-Nitrosylation at the active site decreases the ubiquitin-conjugating activity of ubiquitin-conjugating enzyme E2 D1 (UBE2D1), an ERAD-associated protein 910 915 EN Kana Fujikawa Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Kengo Nakahara Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Tadashi Nishiya School of Pharmaceutical Sciences, Ohu University Akihiro Ito School of Life Sciences, Tokyo University of Pharmacy and Life Sciences Koji Uchida Laboratory of Food Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo Takashi Uehara Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University S-Nitrosylation of protein cysteine thiol is a post-translational modification mediated by nitric oxide (NO). The overproduction of NO causes nitrosative stress, which is known to induce endoplasmic reticulum (ER) stress. We previously reported that S-nitrosylation of protein disulfide isomerase (PDI) and the ER stress sensor inositol-requiring enzyme 1 (IRE1) decreases their enzymatic activities. However, it remains unclear whether nitrosative stress affects ER-associated degradation (ERAD), a separate ER stress regulatory system responsible for the degradation of substrates via the ubiquitin-proteasomal pathway. In the present study, we found that the ubiquitination of a known ERAD substrate, serine/threonine-protein kinase 1 (SGK1), is attenuated by nitrosative stress. C-terminus of Hsc70-interacting protein (CHIP) together with ubiquitin-conjugating enzyme E2 D1 (UBE2D1) are involved in this modification. We detected that UBE2D1 is S-nitrosylated at its active site, Cys85 by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Furthermore, in vitro and cell-based experiments revealed that S-nitrosylated UBE2D1 has decreased ubiquitin-conjugating activity. Our results suggested that nitrosative stress interferes with ERAD, leading to prolongation of ER stress by co-disruption of various pathways, including the molecular chaperone and ER stress sensor pathways. Given that nitrosative stress and ER stress are upregulated in the brains of patient with Parkinson’s disease (PD) and of those with Alzheimer’s disease (AD), our findings may provide further insights into the pathogenesis of these neurodegenerative disorders. No potential conflict of interest relevant to this article was reported.

Springer Acta Medica Okayama 2190-1678 11 2 2019 The hypoglycemia-prevention effect of sensor-augmented pump therapy with predictive low glucose management in Japanese patients with type 1 diabetes mellitus: a short-term study 97 104 EN Akihiro Katayama Diabetes Center, Okayama University Hospital Atsuhito Tone Diabetes Center, Okayama Saiseikai General Hospital Mayu Watanabe Department of Primary Care and Medical Education, Okayama University Sanae Teshigawara Diabetes Center, Okayama Saiseikai General Hospital Satoshi Miyamoto Center for Innovative Clinical Medicine, Okayama University Hospital Jun Eguchi Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Atsuko Nakatsuka Okayama Univ, Dept Med & Clin Sci, Grad Sch Med Dent & Pharmaceut Sci Kenichi Shikata Center for Innovative Clinical Medicine, Okayama University Hospital Jun Wada Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Aims/introduction</br> The predictive low glucose management (PLGM) system was introduced in March 2018 in Japan. Although there are some reports demonstrating the benefit of PLGM in preventing hypoglycemia, no data are currently available in Japanese patients with type 1 diabetes mellitus (T1DM). The aim of the present study is to evaluate the effect of PLGM with sensor-augmented pump therapy in the prevention of hypoglycemia in Japanese patients.</br> Materials and methods</br> We included 16 patients with T1DM who used the MiniMed®640G system after switching from the MiniMed®620G system. We retrospectively analysed the data of the continuous glucose monitoring system in 1 month after switching to MiniMed®640G.</br> Results</br> The area under the curve (AUC) of hypoglycemia of < 70 mg/dL was lowered from 0.42 ± 0.43 mg/dL day to 0.18 ± 0.18 mg/dL day (P = 0.012). Correspondingly, the duration of severe hypoglycemia (< 54 mg/dL) was reduced significantly from 15.3 ± 21.7 min/day to 4.8 ± 6.9 min/day (P = 0.019). The duration of hypoglycemia was reduced, but the reduction was not significant. Regarding the AUC for hyperglycemia > 180 mg/dL and the duration of hyperglycemia did not change. With the PLGM function, 79.3% of the predicted hypoglycemic events were avoided.</br> Conclusions</br> The hypoglycemia avoidance rate was comparable to those in previous reports. In addition, we demonstrated that PLGM can markedly suppress severe hypoglycemia without deteriorating glycemic control in Japanese T1DM patients. It is necessary to further investigate the effective use of the PLGM feature such as establishing a lower limit and the timing of resumption. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2019 Localization of the ultraviolet-sensor Opn5m and its effect on myopia-related gene expression in the late-embryonic chick eye EN Mutsuko Kato Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 20904479 2019 CO2 concentration measurements inside expansion-compression engine under high EGR conditions using an infrared absorption method EN Fatma B.M. Ahmed Department of Physics, Faculty of Science, Aswan University Mohamed F.C. Esmail Department Mechanical Power Engineering, Faculty of Energy Engineering, Aswan University Nobuyuki Kawahara Department of Mechanical Engineering, Okayama University Eiji Tomita Department of Mechanical Engineering, Okayama University The purpose of this study is to measure the high concentrations of CO2 near a spark plug inside an internal combustion engine, and an infrared absorption method is used for the measurement. The spark plug sensor was adapted to a compression-expansion machine, and the CO2 concentration near the spark plug was measured by adding a gas mixture, including CO2 to imitate EGR. Next, the EGR ratio was changed from 10 to 40%, and the CO2 concentration was measured. The effect of the CO2 on the flame propagation was investigated by visualizing the bottom view of the compression-expansion machine. The measurements of CO2 mass concentration are in agreement with those predicted by direct-absorption spectroscopy fundamental theory from the crank angle −60 to −15 deg ATDC. The error was less than 20%, and under the conditions with an EGR ratio of 20–40%. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0360-4012 97 5 2018 Enhanced oxidative stress and the treatment by edaravone in mice model of amyotrophic lateral sclerosis 607 609 EN Yasuyuki Ohta Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Emi Nomura Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Jingwei Shang Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tian Feng Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yong Huang Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Xia Liu Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Xiaowen Shi Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yumiko Nakano Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nozomi Hishikawa Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kota Sato Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Mami Takemoto Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toru Yamashita Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Koji Abe Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Oxidative stress is associated with the degeneration of both motor neurons and skeletal muscles in amyotrophic lateral sclerosis (ALS). A free radical scavenger edaravone has been proven as a therapeutic drug for ALS patients, but the neuroprotective mechanism for the oxidative stress of ALS has not been fully investigated. In this study, we investigated oxidative stress in ALS model mice bearing both oxidative stress sensor nuclear erythroid 2-related factor 2 (Nrf2) and G93A-human Cu/Zn superoxide dismutase (Nrf2/G93A) treated by edaravone. In vivo Nrf2 imaging analysis showed the accelerated oxidative stress both in spinal motor neurons and lower limb muscles of Nrf2/G93A mice according to disease progression in addition to the enhancement of serum oxidative stress marker dROMS. These were significantly alleviated by edaravone treatment accompanied by clinical improvements (rotarod test). The present study suggests that in vivo optical imaging of Nrf2 is useful for detecting oxidative stress in ALS, and edaravone alleviates the degeneration of both motor neurons and muscles related to oxidative stress in ALS patients. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 24701343 4 12 2019 Characterization of Pieces of Paper That Form Reagent Containers for Use as Portable Analytical Devices 15249 15254 EN Supatana Buking Flow Innovation-Research for Science and Technology Laboratories (FIRST Labs) and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University Yusuke Suedomi Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Duangjai Nacapricha Flow Innovation-Research for Science and Technology Laboratories (FIRST Labs) and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University Takashi Kaneta Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Reagent-deposited pieces of paper were characterized by the use of a compact conductometer, a compact pH sensor, and a conventional spectrophotometer to assess their suitability for use as reagent containers. The pieces of paper were fabricated by wax printing to form a limited hydrophilic area to which a consistent volume of an aqueous reagent could be added. The pieces of paper without the reagent increased the conductivity of water gradually because of the release of sodium salts, whereas pH of NaOH decreased because of the acidity of the functional groups in the paper. Three reagents, sulfamic acid as an acid, Na2CO3 as a base, and BaCl2 as a metal salt, were deposited on the pieces of paper to evaluate their ability to release from the pieces of paper. Sulfamic acid and Na2CO3 were released in quantities of 58 and 73% into water after 420 s, whereas 100% of BaCl2 was released after 480 s. The conductometric titrations of NaOH, HCl, and Na2SO4, and the spectrophotometry of Fe2+ were examined using the pieces of paper that contained sulfamic acid, Na2CO3, BaCl2, and 1,10-phenanthroline. Titrations using the pieces of paper suggested that the reagents were quantitatively released into the titrant, which resulted in a linear relationship between the endpoints and the equivalent points. In 120 s of soaking time, 60-70% of the reagents were released. The spectrophotometric measurements of Fe2+ indicated that when an excess amount of the reagents was deposited onto the pieces of paper, they nonetheless sufficiently fulfilled the role of a reagent container. No potential conflict of interest relevant to this article was reported.

Elsevier B.V Acta Medica Okayama 24055808 19 2019 Localization of the ultraviolet-sensor Opn5m and its effect on myopia-related gene expression in the late-embryonic chick eye 100665 EN Mutsuko Kato Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Keita Sato Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Munenori Habuta Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hirofumi Fujita Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tetsuya Bando Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuki Morizane Department of Ophthalmology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Fumio Shiraga Department of Ophthalmology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science Satoru Miyaishi Department of Legal Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hideyo Ohuchi Department of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Recent studies show that exposure to ultraviolet (UV) light suppresses ocular elongation, which causes myopia development. However, the specific mechanisms of this process have not been elucidated. A UV-sensor, Opsin 5 (Opn5) mRNA was shown to be present in extraretinal tissues. To test the possibility that UV-signals mediated by Opn5 would have a direct effect on the outer connective tissues of the eye, we first examined the expression patterns of a mammalian type Opn5 (Opn5m) in the late-embryonic chicken eye. Quantitative PCR showed Opn5m mRNA expression in the cornea and sclera. The anti-Opn5m antibody stained a small subset of cells in the corneal stroma and fibrous sclera. We next assessed the effect of UV-A (375 nm) irradiation on the chicken fibroblast cell line DF-1 overexpressing chicken Opn5m. UV-A irradiation for 30 min significantly increased the expression of Early growth response 1 (Egr1), known as an immediate early responsive gene, and of Matrix metalloproteinase 2 (Mmp2) in the presence of retinal chromophore 11-cis-retinal. In contrast, expression of Transforming growth factor beta 2 and Tissue inhibitor of metalloproteinase 2 was not significantly altered. These results indicate that UV-A absorption by Opn5m can upregulate the expression levels of Egr1 and Mmp2 in non-neuronal, fibroblasts. Taken together with the presence of Opn5m in the cornea and sclera, it is suggested that UV-A signaling mediated by Opn5 in the extraretinal ocular tissues could influence directly the outer connective tissues of the chicken late-embryonic eye. No potential conflict of interest relevant to this article was reported.

ELSEVIER GMBH Acta Medica Okayama 14384221 306 8 2016 Role of a sensor histidine kinase ChiS of Vibrio cholerae in pathogenesis 657 665 EN Rhishita Chourashi Division of Biochemistry, National Institute of Cholera and Enteric Diseases Moumita Mondal Division of Biochemistry, National Institute of Cholera and Enteric Diseases Ritam Sinha Division of Bacteriology, National Institute of Cholera and Enteric Diseases Anusuya Debnath Division of Biochemistry, National Institute of Cholera and Enteric Diseases Suman Das Division of Biochemistry, National Institute of Cholera and Enteric Diseases Hemanta Koley Division of Bacteriology, National Institute of Cholera and Enteric Diseases Nabendu Sekhar Chatterjeea Division of Biochemistry, National Institute of Cholera and Enteric Diseases Vibrio cholera survival in an aquatic environment depends on chitin utilization pathway that requires two factors, chitin binding protein and chitinases. The chitinases and the chitin utilization pathway are regulated by a two-component sensor histidine kinase ChiS in V. cholerae. In recent studies these two factors are also shown to be involved in V. cholerae pathogenesis. However, the role played by their upstream regulator ChiS in pathogenesis is yet to be known. In this study, we investigated the activation of ChiS in presence of mucin and its functional role in pathogenesis. We found ChiS is activated in mucin supplemented media. The isogenic chiS mutant (ChiS-) showed less growth compared to the wild type strain (ChiS+) in the presence of mucin supplemented media. The ChiS- strain also showed highly retarded motility as well as mucin layer penetration in vitro. Our result also showed that ChiS was important for adherence and survival in HT-29 cell. These observations indicate that ChiS is activated in presence of intestinal mucin and subsequently switch on the chitin utilization pathway. In animal models, our results also supported the in vitro observation. We found reduced fluid accumulation and colonization during infection with ChiS- strain. We also found ChiS- mutant with reduced expression of ctxA, toxT and tcpA. The cumulative effect of these events made V. cholerae ChiS- strain hypovirulent. Hence, we propose that ChiS plays a vital role in V. cholerae pathogenesis. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2018 High calcium enhances the expression of double-stranded RNA sensors and antiviral activity in epidermal keratinocytes EN Yuriko Yamamura Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University No potential conflict of interest relevant to this article was reported.

岡山大学教師教育開発センター Acta Medica Okayama 2186-1323 8 2018 生活体験と科学的定義とのギャップを 解消するための新たな授業展開 31 43 EN Shuuichi Inada Shinichi Arano Yoshihiko Inada Makoto Sugiyama Etsumasa Hiura Ryousuke Furujyou Toshimi Nakakura Mikiha Nose Yasuharu Iwamoto 10.18926/CTED/55805 理科の授業では，物理量の定義を起点として学びの展開を構成する場合が多い（定義起点展開法）。一方，日常生活では，「目的地までの所用時間の短さ」と「速さ」を連動させて思考することが多い（生活起点展開法）。そのため，科学的定義に基づく扱いとのギャップに生徒が戸惑い，理科の学習内容を日常生活へ関連させて理解するときの障壁になっている可能性がある。中学校２・３年生679名を対象とした事前調査では，速さについて「生活起点」で考えている生徒が615名（90.6％），「定義起点展開法」で考えている生徒が51名（7.5％）であった。また，生徒の「速さ」の捉え方に対する回答反応時間の分析結果からも，「定義起点展開法」の正解者の反応時間の平均が22.0秒に比べ「生活起点展開法」の平均は18.4秒であり，「目的地までの所用時間の短さ」と「速さ」を連動して思考する「生活起点展開法」の考え方が多いと推測される。 No potential conflict of interest relevant to this article was reported.

American Institute Of Physics Acta Medica Okayama 0034-6748 88 6 2017 Fast x-ray detector system with simultaneous measurement of timing and energy for a single photon 063105 EN Takahiko Masuda Research Institute for Interdisciplinary Science, Okayama University S. Okubo Graduate School of Natural Science and Technology, Okayama University H. Hara Research Institute for Interdisciplinary Science, Okayama University T. Hiraki Research Institute for Interdisciplinary Science, Okayama University S. Kitao Research Reactor Institute, Kyoto University Y. Miyamoto Research Institute for Interdisciplinary Science, Okayama University K. Okai Graduate School of Natural Science and Technology, Okayama University R. Ozaki Graduate School of Natural Science and Technology, Okayama University N. Sasao Research Institute for Interdisciplinary Science, Okayama University M. Seto Research Reactor Institute, Kyoto University S. Uetake Research Institute for Interdisciplinary Science, Okayama University A. Yamaguchi Quantum Metrology Laboratory, RIKEN Y. Yoda Japan Synchrotron Radiation Research Institute A. Yoshimi Research Institute for Interdisciplinary Science, Okayama University K. Yoshimura Research Institute for Interdisciplinary Science, Okayama University We developed a fast X-ray detector system for nuclear resonant scattering (NRS) experiments. Our system employs silicon avalanche photo-diode (Si-APD) as a fast X-ray sensor. The system is able to acquire both timing and energy of a single X-ray photon simultaneously in a high rate condition, 106 counts per second for one Si-APD. The performance of the system was investigated in SPring-8, a synchrotron radiation facility in Japan. Good time resolution of 120 ps (FWHM) was achieved with a slight tail distribution in the time spectrum by a level of 10-9 at 1 ns apart from the peak. Using this system, we successfully observed the NRS from the 26.27-keV level of mercury-201, which has a half-life of 630(50) ps. We also demonstrated the reduction of background events caused by radioactive decays in a radioactive sample by discriminating photon energy. No potential conflict of interest relevant to this article was reported.

American Society for Biochemistry and Molecular Biology Acta Medica Okayama 0021-9258 292 23 2017 Crystal structure and redox properties of a novel cyanobacterial heme protein with a His/Cys heme axial ligation and a Per-Arnt-Sim (PAS)-like domain 9599 9612 EN Taiki Motomura the Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University Michihiro Suga the Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University Rainer Hienerwadel the Laboratoire de Génétique et Biophysique des Plantes, UMR 7265, CNRS-CEA-Aix-Marseille Université, Faculté des Sciences de Luminy Akiko Nakagawa the Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University Thanh-Lan Lai iBiTec-S Wolfgang Nitschke the Laboratoire de Bioénergétique et Ingénierie des Protéines Takahiro Kuma the Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University Miwa Sugiura the Proteo-Science Research Center, Ehime University Alain Boussac iBiTec-S Jian-Ren Shen the Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University Photosystem II catalyzes light-induced water oxidation leading to the generation of dioxygen indispensable for sustaining aerobic life on Earth. The Photosystem II reaction center is composed of D1 and D2 proteins encoded by psbA and psbD genes, respectively. In cyanobacteria, different psbA genes are present in the genome. The thermophilic cyanobacterium Thermosynechococcus elongatus contains three psbA genes: psbA1, psbA2, and psbA3, and a new c-type heme protein, Tll0287, was found to be expressed in a strain expressing the psbA2 gene only, but the structure and function of Tll0287 are unknown. Here we solved the crystal structure of Tll0287 at a 2.0 Å resolution. The overall structure of Tll0287 was found to be similar to some kinases and sensor proteins with a Per-Arnt-Sim-like domain rather than to other c-type cytochromes. The fifth and sixth axial ligands for the heme were Cys and His, instead of the His/Met or His/His ligand pairs observed for most of the c-type hemes. The redox potential, E½, of Tll0287 was -255 ± 20 mV versus normal hydrogen electrode at pH values above 7.5. Below this pH value, the E½ increased by ≈57 mV/pH unit at 15 °C, suggesting the involvement of a protonatable group with a pKred = 7.2 ± 0.3. Possible functions of Tll0287 as a redox sensor under microaerobic conditions or a cytochrome subunit of an H2S-oxidizing system are discussed in view of the environmental conditions in which psbA2 is expressed, as well as phylogenetic analysis, structural, and sequence homologies. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 2186-7755 106 2017 果樹における水分ストレスによる 果実成分の制御と葉内水分の計測 43 49 EN Kunihisa Morinaga Graduate School of Environmental and Life Science, Okayama University 　In fruit production, water status during the maturation season has a significant effect on fruit quality, influencing not only sugar but also organic acid and amino acid contents. Water management technology, therefore, is important for improving fruit quality and maintaining yield in Japan. This study firstly discusses extensive research into the effect of irrigation control on each component of grape fruit juice. Secondly, given that real time monitoring of leaf moisture content is essential to controlling water status, a simple estimation method is described. This method involved fixing a “water stress indicator” to the abaxial side of a leaf; the indicator changed color depending on the water status, which could then be evaluated. The water status was assessed against an indicator color scale, based on a property of cobalt （II） chloride that causes it to change color, from blue to light pink, through a hydration reaction between the indicator sheet and the water evaporating from the leaf to which the indicator sheet is affixed. By using this method, estimates were made of decreases under water stress conditions in the water evaporation rate from satsuma mandarin, grapes, peaches, and Japanese pear, based on the time required for the indicator sheet to change color. Thirdly, a new electrical sensor method to investigate water status in fruit tree leaves was developed, and used to measure electro pulse period; the relationship with transpiration rate was then evaluated using a leaf porometer. Pulse period was found to be consistently correlated with transpiration rate. The results indicate that the water status of fruit tree leaves can be estimated by measuring pulse period. This provides an accurate and quick method for detecting water stress, which could potentially be used for other crops that are particularly sensitive to water stress. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 70 4 2016 Safety of Percutaneous Cryoablation in Patients with Painful Bone and Soft Tissue Tumors: A Single Center Prospective Study (SCIRO-1502) 303 306 EN Toshihiro Iguchi Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Jun Sakurai Center for Innovative Clinical Medicine, Okayama University Hospital Takao Hiraki Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hideo Gobara Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroyasu Fujiwara Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yusuke Matsui Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshihisa Masaoka Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Susumu Kanazawa Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Clinical Study Protocols 10.18926/AMO/54509 This single center prospective study is being conducted to evaluate the safety of the cryoablation for patients with pathologically diagnosed painful bone and soft tissue tumors. Enrollment of 10 patients is planned over the 3-year recruitment period. Patients have related local pain after receiving medications or external radiation therapies will be included in this study. Cryoablation will be percutaneously performed under imaging guidance, and a temperature sensor will be used during treatment as necessary. The primary endpoint is prevalence of severe adverse events within 4 weeks after therapy. The secondary endpoint is effectiveness 4 weeks after the procedure. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 128 2 2016 平成27年度岡山医学会賞 がん研究奨励賞（林原賞・山田賞） 99 102 EN Hiromichi Dansako Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences No potential conflict of interest relevant to this article was reported.

Nature Publishing Group Acta Medica Okayama 2045-2322 5 2015 Metamaterial Absorbers for Infrared Detection of Molecular Self-Assembled Monolayers 12570 EN Atsushi Ishikawa Takuo Tanaka The emerging field of plasmonic metamaterials has introduced new degree of freedom to manipulate optical field from nano to macroscopic scale, offering an attractive platform for sensing applications. So far, metamaterial sensor concepts, however, have focused on hot-spot engineering to improve the near-field enhancement, rather than fully exploiting tailored material properties. Here, we present a novel spectroscopic technique based on the metamaterial infrared (IR) absorber allowing for a low-background detection scheme as well as significant plasmonic enhancement. Specifically, we experimentally demonstrate the resonant coupling of plasmonic modes of a metamaterial absorber and IR vibrational modes of a molecular self-assembled monolayer. The metamaterial consisting of an array of Au/MgF2/Au structures exhibits an anomalous absorption at ~3000 cm−1, which spectrally overlaps with C-H stretching vibrational modes. Symmetric/asymmetric C-H stretching modes of a 16-Mercaptohexadecanoic acid monolayer are clearly observed as Fano-like anti-resonance peaks within a broad plasmonic absorption of the metamaterial. Spectral analysis using Fano line-shape fitting reveals the underlying resonant interference in plasmon-molecular coupled systems. Our metamaterial approach achieves the attomole sensitivity with a large signal-to-noise ratio in the far-field measurement, thus may open up new avenues for realizing ultrasensitive IR inspection technologies. No potential conflict of interest relevant to this article was reported.

Nature Publishing Group Acta Medica Okayama 2045-2322 5 2015 Regulation of the unfolded protein response via S-nitrosylation of sensors of endoplasmic reticulum stress 14812 EN Nakato Ryosuke Ohkubo Yu Konishi Akari Shibata Mari Kaneko Yuki Iwawaki Takao Nakamura Tomohiro Lipton Stuart A. Uehara Takashi Protein S-nitrosylation modulates important cellular processes, including neurotransmission, vasodilation, proliferation, and apoptosis in various cell types. We have previously reported that protein disulfide isomerase (PDI) is S-nitrosylated in brains of patients with sporadic neurodegenerative diseases. This modification inhibits PDI enzymatic activity and consequently leads to the accumulation of unfolded/misfolded proteins in the endoplasmic reticulum (ER) lumen. Here, we describe S-nitrosylation of additional ER pathways that affect the unfolded protein response (UPR) in cell-based models of Parkinson's disease (PD). We demonstrate that nitric oxide (NO) can S-nitrosylate the ER stress sensors IRE1α and PERK. While S-nitrosylation of IRE1α inhibited its ribonuclease activity, S-nitrosylation of PERK activated its kinase activity and downstream phosphorylation/inactivation or eIF2α. Site-directed mutagenesis of IRE1α(Cys931) prevented S-nitrosylation and inhibition of its ribonuclease activity, indicating that Cys931 is the predominant site of S-nitrosylation. Importantly, cells overexpressing mutant IRE1α(C931S) were resistant to NO-induced damage. Our findings show that nitrosative stress leads to dysfunctional ER stress signaling, thus contributing to neuronal cell death. No potential conflict of interest relevant to this article was reported.

Taylor and Francis Acta Medica Okayama 0169-1864 27 15 2013 Positioning device for outdoor mobile robots using optical sensors and lasers 1147 1160 EN Isaku Nagai Genki Yamauchi Keiji Nagatani Keigo Watanabe Kazuya Yoshida We propose a novel method for positioning a mobile robot in an outdoor environment using lasers and optical sensors. Position estimation via a noncontact optical method is useful because the information from the wheel odometer and the global positioning system in a mobile robot is unreliable in some situations. Contact optical sensors such as computer mouse are designed to be in contact with a surface and do not function well in strong ambient light conditions. To mitigate the challenges of an outdoor environment, we developed an optical device with a bandpass filter and a pipe to restrict solar light and to detect translation. The use of two devices enables sensing of the mobile robot’s position, including posture. Furthermore, employing a collimated laser beam allows measurements against a surface to be invariable with the distance to the surface. In this paper, we describe motion estimation, device configurations, and several tests for performance evaluation. We also present the experimental positioning results from a vehicle equipped with our optical device on an outdoor path. Finally, we discuss an improvement in postural accuracy by combining an optical device with precise gyroscopes. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 0007-0963 171 3 2014 Cathelicidin antimicrobial peptide LL-37 augments interferon-beta expression and antiviral activity induced by double-stranded RNA in keratinocytes 492 498 EN T Takiguchi S Morizane T Yamamoto A Kajita K Ikeda K Iwatsuki Background Cathelicidin antimicrobial peptide LL-37 has the capacity to kill a wide range of microbes and to modify host immunity. Recently, our group observed that the activation of keratinocytes by LL-37 and DNA greatly increases interferon (IFN)-beta through Toll-like receptor (TLR) 9. However, the effect of LL-37 on the induction of IFN-beta through TLR3, a sensor of double-stranded (ds) RNA, in keratinocytes is not well known. Objectives To investigate whether LL-37 could affect TLR3 signalling and antiviral activity in normal human epidermal keratinocytes (NHEKs). Methods We investigated the production of IFN-beta in NHEKs stimulated with a TLR3 ligand, poly (I:C), in the presence of LL-37. To examine the effect of LL-37 and poly (I:C) on antiviral activity, a virus plaque assay using herpes simplex (HS) virus type-1 was carried out. The uptake of poly (I:C) conjugated with fluorescein isothiocyanate (FITC) into the keratinocytes was observed in the presence of LL-37. Immunostaining for TLR3 and LL-37 was performed using skin samples from HS. Results LL-37 and poly (I:C) synergistically induced the expression of IFN-beta in NHEKs. Furthermore, co-stimulation with LL-37 and poly (I:C) significantly decreased the viral plaque numbers compared with poly (I:C) or LL-37 alone. LL-37 enhanced the uptake of FITC-conjugated poly (I:C) into cells. Immunohistochemical analysis demonstrated that the expression of TLR3 and LL-37 is up-regulated in HS lesions. Conclusions Our findings suggest that LL-37 augments the antiviral activity induced by dsRNA in keratinocytes, which may contribute to the innate immune response to cutaneous viral infections such as HS. No potential conflict of interest relevant to this article was reported.

Elsevier Science Bv Acta Medica Okayama 0006-8993 1473 2012 Impaired response of hypoxic sensor protein HIF-1 alpha and its downstream proteins in the spinal motor neurons of ALS model mice 55 62 EN Kota Sato Nobutoshi Morimoto Tomoko Kurata Takafumi Mimoto Kazunori Miyazaki Yoshio Ikeda Koji Abe We have recently reported spinal blood flow-metabolism uncoupling in an amyotrophic lateral sclerosis (ALS) animal model using Cu/Zn-superoxide dismutase 1 (SOD1)-transgenic (Tg) mice, suggesting a relative hypoxia in the spinal cord. However, the hypoxic stress sensor pathway has not been well studied in ALS. Here, we examined temporal and spatial changes of the hypoxic stress sensor proteins HIF-1 alpha and its downstream proteins (VEGF, HO-1, and EPO) during the normcodccourse of motor neuron (MN) degeneration in the spinal cord of these ALS model mice. We found that HIP-1 alpha protein expression progressively increased both in the anterior large MNs and the surrounding glial cells in Tg mice from early symptomatic 14 week (W) and end stage 18W. Double immunofluorescence analysis revealed that HIP-1 alpha, plus GFAP and Iba-1 double-positive surrounding glial cells, progressively increased from 14 W to 18 W, although the immunohistochemistiy in large MNs did not change. Expression levels of VEGF and HO-1 also showed a progressive increase but were significant only in the surrounding glial cells at 18W. In contrast, EPO protein expression was decreased in the surrounding glial cells of Tg mice at 18W. Because HIF1-alpha serves as an important mediator of the hypoxic response, these findings indicate that MNs lack the neuroprotective response to hypoxic stress through the HIF-1 alpha system, which could be an important mechanism of neurodegeneration in ALS. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 68 3 2014 Alternative Placement of Bispectral Index Electrode for Monitoring Depth of Anesthesia during Neurosurgery 151 155 EN Phuping Akavipat Nate Hungsawanich Rungruedee Jansin Original Article 10.18926/AMO/52655 In neurosurgery in particular, the recommended placement of electrodes for monitoring depth of anesthesia during surgery sometimes conflicts with the surgical site or patient positioning. Therefore, we proposed this study to evaluate the agreement and correlation of bispectral index values recorded from the usual frontal area and the alternate, post-auricular areas in neurosurgery patients. Thirty-four patients scheduled for neurosurgery under general anesthesia were included. Bispectral index (BIS) sensors were placed at both the frontal and post-auricular areas. The anesthesia given was clinically adjusted according to the frontal (standard) BIS reading. The BIS values and impedance were recorded;Pearsonʼs correlation and Bland-Altman plots were analyzed. The bias ± 2SD for the electrode placement before, during, and post-anesthesia were 0±23.32, 1.5±10.69, and 2.1±13.52, while the limits of agreement were −23.3 to 23.3, −12.2 to 9.2, and −17.7 to 13.5, respectively. The correlation coefficient between frontal- and post-auricular-area electrodes was 0.74 with a p-value ＜0.001.The post-auricular placement of a BIS electrode is a practical alternative to frontal lobe placement. Nevertheless, proper electrode location is important to minimize error. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2014 Impaired response of hypoxic sensor protein HIF-1α and its downstream proteins in the spinal motor neurons of ALS model mice EN Kota Sato No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2041-1723 4 2013 An essential role for the N-terminal fragment of Toll-like receptor 9 in DNA sensing EN Masahiro Onji Atsuo Kanno Shin-Ichiroh Saitoh Ryutaro Fukui Yuji Motoi Takuma Shibata Fumi Matsumoto Aayam Lamichhane Shintaro Sato Hiroshi Kiyono Kazuhide Yamamoto Kensuke Miyake Toll-like receptor 9 (TLR9) is an innate immune sensor for microbial DNA that erroneously responds to self DNA in autoimmune disease. To prevent autoimmune responses, Toll-like receptor 9 is excluded from the cell surface and silenced until the N-terminal half of the ectodomain (TLR9N) is cleaved off in the endolysosome. Truncated Toll-like receptor 9 (TLR9C) senses ingested microbial DNA, although the precise role of the truncation remains controversial. Here we show that TLR9 is expressed on the surface of splenic dendritic cells. Following the cleavage of TLR9 in the endolysosome, N-terminal half of the ectodomain remains associated with truncated TLR9, forming the complex TLR9N + C. The TLR9-dependent cytokine production by Tlr9(-/-) dendritic cells is rescued by a combination of TLR9N and TLR9C, but not by TLR9C alone. These results demonstrate that the TLR9N + C complex is a bona fide DNA sensor. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 0924-4247 184 2012 An ultrasonic motor for cryogenic temperature using bolt-clamped Langevin-type transducer 134 140 EN Daisuke Yamaguchi Takefumi Kanda Koichi Suzumori In this study, a small ultrasonic motor driven under cryogenic temperature conditions has been fabricated and evaluated. Since transducer performance generally decreases at cryogenic temperatures, we designed and fabricated a bolt-clamped Langevin-type transducer for operation at cryogenic temperature. We simulated the influence of thermal stress on the transducer. The results from simulation were used to design the transducer, and it was then used to fabricate an ultrasonic motor for cryogenic temperature. The maximum diameter and the height of the motor are 30 mm and 38.7 mm. To enable the motor to be driven at cryogenic temperature, we evaluated the relationship between the contact pre-load and the lowest rotatable temperature. The motor's driving performance was evaluated at both room temperature and cryogenic temperatures. In a 4.5 K helium gas ambient, the rotation speed and starting torque were 133 rpm and 0.03 mu N m when the applied voltage was 50 Vp-p. No potential conflict of interest relevant to this article was reported.

Hindawi Publishing Corporation Acta Medica Okayama 2012 2012 Theoretical Study on the Detection of Tilted Lipid Bilayers Using Surface Plasmon Resonance Techniques EN Koyo Watanabe Koji Matsuura Effective refractive indices detected using surface plasmon resonance techniques are calculated as a function of the tilt angle of lipid bilayers in a multilayered model. The changes in the effective refractive indices are derived from the shift of an excitation angle of surface plasmon. To obtain effective refractive index plots, we determined refractive index changes in the lipid bilayers with 3 and 5 nm thicknesses as a function of tilt angle and obtained a relationship between the effective refractive index and tilt angle. We also showed that the effective refractive index depended on the lipid bilayers thickness and anisotropic permittivities, which vary with interchain distance. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 0924-4247 164 1-2 2010 Multiplex pneumatic control method for multi-drive system 88 94 EN Yasutaka Nishioka Koichi Suzumori Takefumi Kanda Shuichi Wakimoto Pneumatic actuators have several advantages such as light weight safety low cost and high compliance However many pneumatic actuators have complicated systems that include a compressor air tubes and pneumatic valves with electrical wires This research proposes a new control method for a multiplex pneumatic transmission constructed with special resonant valves and air tubes with a control system driven by air vibration in air tubes without electrical wires The control is simplified and effective for pneumatic systems having many degrees of freedom In this paper the development of a primitive model of the resonant valve and a prototype valve is described In addition two control methods which are a superimposing method and a time-sharing method are shown and the independent driving of four actuators is realized by using one of the control methods with air tubes only. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 0169-1864 24 10 2010 Development of an Intelligent Chair Tool System Applying New Intelligent Pneumatic Actuators 1503 1528 EN Ahmad 'Athif Mohd Faudzi Koichi Suzumori Shuichi Wakimoto This paper develops an Intelligent Chair Tool (ICT) - a new chair-type human and machine interaction seating system powered by 36 intelligent pneumatic actuators. This tool can be used to facilitate investigation of chair shapes from spring and damping effects of seating and backrest surfaces. Each actuator used consists of five extensive elements of encoder, laser strip rod, pressure sensor, valves and PSoC microcontroller incorporated in a single device. By using the ICT, different shapes, spring and damping characteristics can be obtained to aid the design of chairs from the control inputs, i.e., position x, stiffness k(s) and viscous coefficient c. Several control algorithms are presented to realize the communication and control system, and to obtain all data in real-time. The control methodology presented contains an inner force loop and an outer position loop implemented using a unified control system. The specification, development design and experimental evaluation of the ICT control system and actuator used are presented and discussed. No potential conflict of interest relevant to this article was reported.

Elsevier Science B.V. Acta Medica Okayama 0167-577X 65 14 2011 Effect of varying the ratio of matrix/dispersoid particle size on the piezoresistivity of alumina/carbon-black composite ceramics 2197 2200 EN Akira Kishimoto Yuto Takagawa Takashi Teranishi Hidetaka Hayashi Alumina/carbon-black composite ceramics with different percolation thresholds were fabricated by changing the size ratio of constituent particles. The dependence of resistivity on pressure was established for each sample. The compositional dependence of resistivity can be explained by percolation theory. The percolation threshold decreases with increasing alumina/carbon-black particle size ratio. The pressure dependence of the resistivity increases as the composition approaches the percolation threshold. When the relative composition at the percolation threshold is fixed, the sensitivity increases with increasing matrix/dispersoid initial particle size ratio. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 123 1 2011 アンフィファイジンとN-WASPのダイナミックな相互作用は，アクチン重合を制御する 1 11 EN Hiroshi Yamada Sergi Padilla-Parra Sun Joo Park Toshiki Itoh Mathilde Chaineau Ilaria Monaldi Ottavio Cremona Fabio Benfenati Pietro De Camilli Maïté Coppey-Moisan Marc Tramier Thierry Galli Kohji Takei No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 101 7-8 1989 Pusher plate pump varible rate modeによる左心バイパス法の研究―特に，左室局所心筋血流量による検討― 711 721 EN Kazuo Shiotsu Left heart bypass (LHB) was performed in goats with normal ventricles and in those with LV failure. A pneumatic type pusher-plate pump can be operated in fixed rate, synchronous mode variable pulse rate (VR). In this experiment, the pump was operated in VR, that is, the pusher-plete position signal from a hall effect sensor was utilized to regulate the pump stroke at a constant level, but its rate was allowed to vary automatically depending on the preload and afterload. LHB was performed in 12 goats with normal ventricles. Blood was drained from the left atrium and was returned to the descending aorta. Pump flows averaged 61.3% of cardiac output (CO). When bypass was started, CO decreased from 72.5 to 57.2 ml/min/kg (p<0.005), and LV(max dp/dt) decreased from 3943 to 2989 mmHg/sec (p<0.05). Atrial pressure (AP), A-VDO(2), pulmonary atrial pressure (PAP) and TTI did not show significant changes. Regional myocardial blood flow (RMBF), which was measured using the hydogen gas clearance method, decreased from 128 to 85 ml/min/100g (p<0.05). In 12 goats, LV failure was induced by injecting 0.08 ml/kg of 5N NaOH into the LV free wall. The weight ratio of myocardial necrosis to the LV free wall was 22.7%. Pump flows averaged 52.5% of CO. When bypass was started, CO increased from 45.7 to 61.4 (p<0.005). AP increased from 85.2 to 124 (p<0.001), A-VDO(2) decreased from 6.08 to 4.74 vol% (p<0.01) and PAP decreased from 33.2 to 30.3 (p<0.02). LV(max dp/dt) and TTI did not show significant changes. RMBF, which was determined at normal LV free wall, decreased from 98.6 to 76.1 (p<0.05). These data suggest that LHB is more effective in goats with LV failure than in those with normal ventricles in terms of left ventricular and systemic circulatory support. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 127 1 2006 A micro ultrasonic motor using a micro-machined cylindrical bulk PZT transducer 131 138 EN Takefumi Kanda Akira Makino Tomohisa Ono Koichi Suzumori Takeshi Morita Minoru Kuribayashi Kurosawa <p>In this paper, a micro ultrasonic motor using a micro-machined bulk piezoelectric transducer is introduced. The cylindrical shaped bulk piezoelectric transducer, a diameter of 0.8 mm and a height of 2.2 mm, was developed as stator transducer for traveling wave type ultrasonic motor. The transducer was made of lead zirconate titanate (PZT) bulk ceramics, and formed by micro machining, Ni plating and laser beam cutting process. Using this stator transducer, we have fabricated a cylindrical micro ultrasonic motor, a diameter of 2.0 mm and a height of 5.9 mm. We have also evaluated some characteristics and succeeded in driving the micro ultrasonic motor.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 1999 Development of measuring method for softness of epidermis using rotational step response 359 364 EN Yoshitake Yamamoto Keisuke Kawai <p>We have proposed a new measuring method for the softness of epidermis using rotational step response. It can be proceeded that horizontal torsional step is given periodically to the human skin surface by rotational step motor. Then dynamically epidermal characteristic is abstracted selectively from the human skin minimizing influence of the subcutaneous tissue. The cylindrical rotor is attached to the shaft of step motor and its external area is surrounded by the cylindrical guard ring; therefore, only human skin surface of inside the guard ring is screwed periodically by its rotor. At this moment, viscoelasticity of the epidermis is evaluated from analyzing the inducting coil of the step motor. The waveform of voltage of inducing coil can be characterized by overshoot P1, damping ratio D and undamped natural frequency &#969;n. The softness Ks that indicates viscoelasticity of the epidermis can be calculated from these parameters. Many experimental results showed that the softness Ks corresponds to the human sense and it is rational as a parameter for the human skin characteristics. This system is very useful as the measurement can be done easily, in vivo, and non-invasively. It also can be constructed simply without special mechanical sensor because step motor acts as not only driving but also sensing </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1990 A venous occlusion plethysmography using a load cell as the sensing element 38 42 EN Yoshitake Yamamoto Tatsuya Yamamoto P. Ake Oberg Akiharu Yoshida <p>An application of the load cell as a sensor in venous occlusion plethysmography is presented. In this method the limb volume changes that follow venous occlusion are converted into water volume changes using a water tank for volume change detection. The hydrostatic pressure, as well as the water surface level, is measured and used for the calculation of the volume change. By using this method the influence of water pressure on limb blood flow, as well as drift and leakage of the sensing element, is avoided. The load cell has the advantage of measuring the weight of the displaced water volume, which simplifies the design principles of the plethysmography. The plethysmography is found to be sensitive, highly linear, and easy to handle. It has been evaluated in several subjects, and the results of these studies are in agreement with earlier results </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 133 2 2008 Analysis of response mechanism of a proton-pumping gate FET hydrogen gas sensor in air 538 542 EN Tomiharu Yamaguchi Masanori Takisawa Toshihiko Kiwa Hironobu Yamada Keiji Tsukada <p>Two different types of hydrogen response signals (DC and AC) of a proton-pumping gate FET with triple layer gate structure (Pd/proton conducting polymer/Pt) were obtained. The proton-pumping gate FET showed good selectivity against other gases (CH₄, C₂H₆, NH₃, and O₂). For practical use, the hydrogen response characteristics of the proton-pumping gate FET were investigated in air (a gaseous mixture of oxygen and nitrogen). The proton-pumping gate FET showed different hydrogen response characteristics in nitrogen as well as in air, despite the lack of oxygen interference independently. To clarify the response mechanism of the proton-pumping gate FET, a hydrogen response measurement was performed, using a gas flow system and electrochemical impedance spectroscopy. Consequently, the difference in response between nitrogen and air was found to be due to the hydrogen dissociation reaction and the interference with the proton transfer caused by the adsorbed oxygen on the upper Pd gate electrode</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 39 6 1990 A venous occlusion plethysmography using a load cell as the sensing element 987 990 EN Yoshitake Yamamoto Tatsuma Yamamoto P. Ake Oberg Akiharu Yoshida <p>An application of the load cell as a sensor in venous occlusion plethysmography, which is a well-established method for limb or digit blood-flow measurements is presented. In this method, the limb volume changes that follow venous occlusion are transferred into the volume change of a water pool. The hydrostatic pressure as well as the water surface level are measured and used for the calculation of the volume change. By using this method, the influence of water pressure on limb blood flow is avoided together with drift and leakage of the sensing element. The load cell has the advantage that it measures the weight of the displaced water volume, which simplifies the design principles of the plethysmography. The plethysmography is found to be sensitive, highly linear, and easy to handle. The results of using a manufactured water-displacement plethysmography to determine actual blood-flow measurements in forearms and fingers are presented </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1997 Obstacle avoidance by changing running path for an autonomous running vehicle applying visual servoing 106 111 EN Akira Gofuku Yutaka Tanaka Hiroyoshi Soda Isaku Nagai <p>This paper describes an improved running control algorithm based on the visual servoing in consideration of the turning back of a running path to avoid an obstacle on the path by changing the running path. This paper also describes an experimental autonomous running vehicle to demonstrate the algorithm. As a vision sensor, the vehicle equips with a video-rate stereo rangefinder which processes color images from stereo CCD cameras and is developed in the authors' laboratory. From the several basic autonomous running experiments, it is concluded that the experimental vehicle runs smoothly any planned path composed of several teaching routes by transferring routes. It is also concluded that the vehicle can turn back on a path including turning back of route transference</p> No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers Acta Medica Okayama 1999 Application of pneumatic parallel manipulator as haptic human interface 185 190 EN Masahiro Takaiwa Toshiro Noritsugu When humans and robots implement a cooperative task, information (intention) transfer between them is an important problem as the task becomes complicated. In the paper, a haptic interface using a pneumatic parallel manipulator is developed to realize “information transfer by means of contact”. The contact information given by the human, namely contact force vector and contact point on the manipulator, is detected by the interface itself and such information is transferred to the robot by being connected with some reference signal. The pneumatic parallel manipulator works as a kind of elastic body even when its position is controlled owing to the air compressibility. Focusing on this characteristic and introducing an idea of compliance center with a spherical shell, contact force vector and contact point are detected without a force sensor. The validity of the proposed method is confirmed through some experiments. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 2002 Pneumatic direct-drive stepping motor for robots 2031 2036 EN Koichi Suzumori Tatsuya Hashimoto Kazuo Uzuka Isao Enomoto <p>A new type of pneumatic stepping motor, named pneumatic nutation motor, was developed. This motor achieves stepping positioning of 720 steps/rotation without any electrical devices or sensors mounted on the servo mechanisms. This makes the motor possible to be used under hazardous conditions such as in water and in strong magnetic fields where conventional electromagnetic motors cannot be used. The motor torque is so big that the motor can be used as a direct motor. In this report, the driving principle and design of this motor are presented. Its characteristics are analyzed experimentally and theoretically. The motors were applied to a parallel linkage mechanism with six degrees of freedom. The mechanism shows that the pneumatic nutation motors can be used as a direct servo motor for robot mechanisms.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 4 2004 Active link mechanisms for physical man-machine interaction 3895 3900 EN Jumpei Ochi Tatsuya Hashimoto Koichi Suzumori Takefumi Kanda <p>&lt;p&gt;In this paper, we propose a new type of haptic interface, named active link mechanism. This device realizes physical man-machine interaction (PMI) between machines and persons. Two prototypes were developed to demonstrate the potential of the active link mechanisms. Developed interface devices are an active tetrahedron and an active icosahedron. Nine-DOF micro spherical joints and pressure control pneumatic cylinders were developed to realize the active tetrahedron, while fifteen-DOF micro spherical joints and intelligent pneumatic cylinders were developed for the active icosahedron. The tetrahedron successfully realizes &quot;virtual touch&quot;; the operators feel actions, forces, and shapes of the virtual objects in PC and also move and deform them. Real time PMI is realized by building the developed devices into MSC.Visual-Nastran4D. MSC.VisuaI-Nastran4D is a mechanism analysis software, which can make motion analysis in real time. The active icosahedron also realized dynamic interaction with virtual objects in PC, showing the potential of the devices as a haptic interface.&lt;/p&gt;</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 3 2003 Development of force displaying device using pneumatic parallel manipulator and application to palpation motion 4098 4103 EN Masahiro Takaiwa Toshiro Noritsugu <p>&#60;P&#62;The goal of this study is to develop a mechanical system which display elastic characteristic like stiffness on the surface of human body aiming at applying to palpation simulator. Pneumatic parallel manipulator is employed as a driving mechanism, consequently, it brings capability of minute force displaying property owing to the air compressibility. Compliance control system without using force/moment sensor is constructed by introducing a disturbance observer and a compliance display scheme is proposed. The validity of the proposed scheme is verified experimentally. </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2004 Development of active icosahedron and its application to virtual clay modeling 175 180 EN Jumpei Ochi Tatsuya Hashimoto Junichi Tanaka Koichi Suzumori Takefumi Kanda <p>We have developed an active link mechanism for physical man-machine interaction. We report an active icosahedron consisting of intelligent cylinders and its application to virtual clay modeling. Intelligent pneumatic cylinders are newly developed to realize active link mechanisms. This cylinder aims at a novel cylinder in which various sensors and control devices are built. Active link mechanisms are highly integrated and enhanced by intelligent cylinders. A control system is built for the active icosahedron. In the control system, a key element is a control program implementing drawing of a virtual model on display and controlling of active links. Virtual clays are deformed by the program based on the apex positions converted from cylinder lengths. The active icosahedron realized dynamic interaction with virtual objects in PC, showing the potential of the devices as a haptic interface.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 2005 A cylindrical micro ultrasonic motor using micro-machined piezoelectric vibrator 721 724 EN Takefumi Kanda Akira Makino Yoshitaka Oomori Koichi Suzumori <p>A micro ultrasonic motor using a micro-machined cylindrical bulk piezoelectric vibrator is introduced. This motor consists of the vibrator, a glass case and a rotor. The diameter of the piezoelectric vibrator is 0.8 mm and that of the motor case is 1.8 mm. Since the stator transducer is fixed at the end of the cylinder, it is easy to support the vibrator and the structure of the motor is not complicated. In addition, the vibrator and rotor are supported by the glass case. This is important for the micro ultrasonic motor because it is difficult to support the vibrator when the vibrator is miniaturized. We have fabricated and evaluated the cylindrical shaped traveling type micro ultrasonic motor using this vibrator.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 2005 Development of intelligent McKibben actuator with built-in soft conductive rubber sensor 745 748 EN Shuichi Wakimoto Koichi Suzumori Takefumi Kanda <p>This study aims at the development of an intelligent McKibben actuator, in which a soft rubber displacement sensor is integrated. Recently, the McKibben actuator has attracted engineers because of light weight, high output power and high compliance. But in the case of using it for servo control at present, the systems need encoders or potentiometers, therefore the systems tend to grow in size and take away from compliance which is an important advantage for a safe and secure mechanism. We have developed a soft displacement sensor and incorporated it in a McKibben actuator, named it the intelligent McKibben actuator, and proved its potential.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2005 Development of intelligent McKibben actuator 487 492 EN Shuichi Wakimoto Koichi Suzumori Takefumi Kanda <p>The aim of this study is to develop an intelligent McKibben actuator with an integrated soft displacement sensor inside, so that displacement of this actuator can be controlled without having any extra devices attached. In addition, the high compliance which is a positive feature of the McKibben actuator is still conserved. This paper consists of four main parts. First of all, different types of soft displacement sensors made out of rubber were composed, and tested for their functional characteristics. Secondly, the intelligent McKibben actuator was developed with the soft displacement sensor incorporated within. Then, experiments of the position servo control with a single intelligent McKibben actuator were carried out. At last a robot arm mechanism was designed with two intelligent McKibben actuators, and those experimental results showed a great potential for its future applications.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 3 2002 Recognition of elastic characteristic of object using pneumatic parallel manipulator 1724 1727 EN Masahiro Takaiwa Toshiro Noritsugu Kenichi Fujie <p>The goal of this study is to develop a mechanical system that can display elastic characteristic of an object aiming at the application in the field of virtual reality. A pneumatic parallel manipulator is introduced as a driving mechanism, which consequently brings the capability of minute force displaying property owing to the air compressibility. A compliance control system without using force/moment sensor is constructed by introducing a disturbance observer, and a compliance display scheme is proposed. The validity of the proposed scheme is verified experimentally. </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 134 2 2008 Oxygen electrode as a new tool to evaluate hydroxyl radical-scavenging ability 516 520 EN Keiko Komagoe Hiroaki Takeuchi Takashi Katsu <p>An oxygen electrode was applied to determine hydroxyl radical ((OH)-O-center dot) levels for the first time. The method is based on the determination of (OH)-O-center dot generated by the Fenton reaction using the reaction of (OH)-O-center dot with a scavenger and the resulting radical consuming an oxygen molecule stoichiometrically. Thus, the (OH)-O-center dot-scavenging abilities of antioxidant reagents, as well as the concentration of (OH)-O-center dot, can be determined by the measurement of consumption of dissolved oxygen using an oxygen electrode. A good correlation between the present method and conventional colorimetry was obtained for the estimation of the (OH)-O-center dot-scavenging activities of antioxidants. Furthermore, the results correlated with the (OH)-O-center dot-scavenging rate constants of the reagents evaluated by a "cupric ion reducing antioxidant capacity (CUPRAC)" assay. We applied the present method to estimate the (OH)-O-center dot-scavenging abilities of commercially available alcoholic drinks.</p> No potential conflict of interest relevant to this article was reported.

Elsevier Science Ltd Acta Medica Okayama 0272-8842 34 4 2008 Improvement of piezoresistance properties of silicon carbide ceramics through co-doping of aluminum nitride and nitrogen 845 848 EN Akira Kishimoto Yasuyuki Okada Hidetaka Hayashi The piezoresistance coefficient was measured on co-doped silicon carbide ceramics. Evaluation samples of alpha-silicon carbide ceramics were first fabricated by glass capsule HIP method using powder mixture of silicon carbide and aluminum nitride with various ratios. The resultant aluminum nitride added silicon carbide ceramics were doped with nitrogen by changing the post-HIP nitrogen gas pressure. The lattice parameter increased with the amount of adding aluminum nitride indicating that the incorporated aluminum substituted smaller silicon atoms. After post-HIP treatment, lattice parameter then decreased with nitrogen gas pressure. The piezoresistive coefficient increased with the addition of aluminum nitride, it further increased with the nitrogen doping pressure. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 2004 A new laser-based position sensor with the ability of detecting the incident angle of a light 1010 1014 EN Mitsuru Baba Norimasa Michiue Daisuke Narita Kozo Ohtani <p>This paper describes a new sensor with the ability of simultaneously detecting the position and the incident angle of a light. The basic principle is to detect the difference in the peak positions between two image sensors. We have designed and build three kinds of prototype of the proposed sensor. We experimentally verified the practicable accuracy of the proposed position sensors.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 1996 A new position sensor for high-speed measurement of multiple points EN Mitsuru Baba Tadataka Konishi Yuko Hori Kouji Otani <p>A high-speed measuring system of multiple points is becoming an important issue in many industrial applications. Therefore, the development of a high-speed position sensor is an important issue. However, conventional sensors such as CCD(charge-coupled device) and PSD(position-sensitive detector) are insufficient to apply to the high-speed measurement of multiple points. We propose a new position sensor for high-speed measurement of multiple points. The proposed sensor features a single scanning detecting method of multiple points by parallel processing technique and design of the sensor by analog circuitry, which makes high-speed measurement of multiple points possible. The designed sensor system realizes both high-speed performance and high accuracy </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 2003 Three-dimensional shape measurement of a transparent object using a rangefinding approach 1022 1027 EN Daisuke Narita Mitsuru Baba Kozo Ohtani <p>This paper describes a non-contact optical measuring approach by which to measure the three-dimensional (3D) shape of a transparent object such as a glass panel or an acrylic plate. In conventional approaches to obtain the 3D shape of a transparent object, contact-type sensors have been widely used. However, the measurement accuracy of contact-type sensors is susceptible to the influence of various factors. In this paper, we propose a novel triangulation-based rangefinding approach that can be applied to the 3D shape of a transparent object or to an opaque object. The rangefinder is based on the fact that the light projected onto the surface of a transparent object is in part reflected by the surface, though the majority of the projected light is transmitted through the surface. From the experimental results, the proposed rangefinding approach has the advantage that it can easily measure the 3D-shape of an object if the object reflects or transmits light, depending on its location. As a result, we conclude that the proposed approach has great potential for a wide range of industrial applications.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 2003 A new sensor system for simultaneously detecting the position and incident angle of a light spot 456 460 EN Norimasa Michiue Mitsuru Baba Kozo Ohtani <p>The present paper describes a newly devised sensor, which has the ability to detect the two-dimensional position and the one-dimensional angle of a light spot simultaneously. Ordinary laser-based measurement systems utilize CCD or PSD sensors. These conventional sensors can detect only a light spot's position. When the sensor can detect the incident angle of a light spot as well as the position, the sensor has a wide range of applicability. The sensor consists of two linear array-type sensors whose depth positions are slightly different. We have designed and built a prototype sensor system. We experimentally verified the practicable accuracy of the present sensor system. We also applied the present sensor system to two typical laser-based measurement systems: 2-D position measurement, and 3-D shape measurement for specular objects. Experimental results show that the sensor system was applicable to a laser-based measurement system. </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 3 1999 Range imaging system with multiplexed structured light by direct space encoding 1437 1442 EN Mitsuru Baba Tadataka Konishi <p>Since practical multiplexed structured light systems currently available use plural light patterns or different illumination conditions to ensure a high reliability, their fast performance is impaired. This paper describes a fast, highly reliable range imaging system with a multiplexed structured light system that uses a direct space encoding approach while using only a single light pattern. Unlike a conventional encoding approach, the proposed approach is unique in that it encodes object space through the use of a special optical system which consists of field stops, plural lenses, and shield masks, rather than a light pattern. The theoretical considerations and experimental results demonstrate that the proposed approach is effective for a highly reliable, fast, accurate range imaging system </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 1997 A new fast rangefinding method based on a non-mechanical scanning mechanism and a high-speed image sensor 957 962 EN Mitsuru Baba Tadataka Konishi Nobuaki Kobayashi <p>In this paper, we present a new fast rangefinding method based on a non-mechanical scanning mechanism and a high-speed image sensor. Although the light stripe rangefinding method often is utilized to measure three dimensional shape of an object, it is difficult to acquire dense range data at high-speed with conventional light stripe rangefinders. We proposed a fast rangefinding method based on two new ideas unlike conventional methods: (1) to move a parabolic light pattern onto the object by means of a non-mechanical mechanism; (2) to detect a true peak value using a high-speed image sensor. We have designed and built a prototype rangefinder. The rangefinder was able to acquire three-dimensional position at 500 ns which is faster than conventional rangefinders. As a result, the proposed method is effective for high-speed three-dimensional measurement </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 3 2002 A new method for 3-D shape measurement and surface reflectance of an object with rangefinder 1409 1410 EN Daisuke Narita Kozo Ohtani Mitsuru Baba <p>An object for computer graphics application requires the following two information: the three dimensional (3D) shape and surface reflectance property of the object. We proposed a 3D shape and surface reflectance measurement system using the new sensor, which can detect the incidence position and the angle of the light simultaneously. Experimental results successfully demonstrate the efficacy of the method.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 3 2004 3D shape recognition system by ultrasonic sensor array and genetic algorithms 1948 1952 EN Mitsuru Baba Kozo Ohatani Syunya Komatsu <p>This paper describes 3D shape recognition system using ultrasound pressure data and a Genetic Algorithm. The ultrasonic 3D shape recognition system using has commonly used a Neural Network (NN). However, a NN perform poorly when lacking learned data. In order to overcome this problem when using a NN, we here attempt to replace the NN with a Genetic Algorithm (GA). Unlike a NN, the GA can recognize shapes without depending on learned data. Experimental results demonstrate that the recognition ratios of the proposed recognition system using the GA are higher than that of a conventional 3D shape recognition system using a NN. Therefore, it is shown that our ultrasonic 3D shape recognition system is effective for many industrial applications. </p> No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 61 3 2007 Calpain-calcineurin signaling in the pathogenesis of calcium-dependent disorder. 123 137 EN Hai-Yan Wu Kazuhito Tomizawa Hideki Matsui Review 10.18926/AMO/32905 Intracellular calcium is a powerful secondary messenger that affects a number of calcium sensors, including calpain, a Ca2+-dependent cysteine protease, and calcineurin, a Ca2+/calmodulin-dependent protein phosphatase. Maintenance of low basal levels of intracellular calcium allows for the tightly regulated physiological activation of these proteins, which is crucial to a wide variety of cellular processes, such as fertilization, proliferation, development, learning, and memory. Deregulation of calpain and calcineurin has been implicated in the pathogenesis of several disorders, including hypertension, heart disease, diabetes, cerebral ischemia, and Alzheimer's disease. Recent studies have demonstrated an interplay between calpain and calcineurin, in which calpain can directly regulate calcineurin activity through proteolysis in glutamate-stimulated neurons in culture and in vivo. The calpain-mediated proteolytic cleavage of calcineurin increases phosphatase activity, which promotes caspase-mediated neuronal cell death. Thus, the activation of the calpain-calcineurin pathway could contribute to calcium-dependent disorders, especially those associated with Alzheimer's disease and myocardial hypertrophy. Here, we focus briefly on recent advances in revealing the structural and functional properties of these 2 calcium-activated proteins, as well as on the interplay between the 2, in an effort to understand how calpain-calcineurin signaling may relate to the pathogenesis of calcium- dependent disorders. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 46 5 1992 Hemodynamic Performance of the Biventricular Bypass System Operated in an Independent Variable Rate Mode 317 321 EN Kozo Ishino Taiji Murakami Hiroyuki Irie Hironobu Nakayama Hiroshi Izumoto Makoto Yamada Hiromichi Teraoka Yoshimasa Sanoo Shigeru Teramoto Article 10.18926/AMO/32662 <p>The present study was undertaken to determine whether a biventricular bypass system operated in an independent variable rate (VR) mode can maintain the entire circulation. Two pusher-plate pumps which incorporated the Hall effect position sensors were used to bypass the right and left ventricles in 10 sheep under fibrillation. The flow distributions of the pump output to the carotid and renal arteries were investigated every 6 h using ultrasonic blood flow meters for 24 h in 5 animals, and the controllability of the VR mode was evaluated in 5 long-term experiments. The carotid artery flow ratio to the pump output decreased significantly from 4.7 +/- 0.8% before the bypass to 2.7 +/- 0.9% after 24 h. However, the renal artery flow ratio did not change throughout the experiments. In the long-term experiments, the animals were kept alive from 3 to 48 days (mean 15.6 days). The mean pump output had been maintained at more than 90 ml/min/kg for the first 7 days. After the surgery, the pump driving conditions were not readjusted in any experiment. The results indicate that the biventricular bypass system operated in the independent VR mode automatically maintains the entire circulation at a satisfactory level.</p> No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 54 2 2000 Possible postsynaptic action of aminoglycosides in the frog rectus abdominis. 49 56 EN Yusuf Karatas Yusuf Ergun Cemil Gocmen Ata Secilmis Ergin Singirik Atilla Dikmen Firuz Bayasal Article 10.18926/AMO/32289 <p>The present study was undertaken to investigate the postsynaptic effects of aminoglycosides on contractions evoked by acetylcholine (ACh), KCl, electrical field stimulation (EFS) and Na(+)- and Ca(2+)-free Ringer solution with 0.2 mM Na2 EDTA (NaFCaFR) in the isolated frog rectus abdominis. Neomycin inhibited contraction elicited by ACh, NaFCaFR, and EFS at the higher frequencies (8 and 10 Hz) but not those elicited by KCl and EFS at the lower frequencies (2, 3 and 5 Hz). D-tubocurarine inhibited ACh-induced contractions in a concentration-dependent manner. In addition, drug reduced EFS-evoked contractions to a limited extent. Lower concentrations (10(-5), 5 x 10(-5), 10(-4), 2 x 10(-4) and 3 x 10(-4) M) but not higher concentrations (4 x 10(-4) and 5 x 10(-4) M) of methoxyverapamil exhibited a concentration-dependent inhibitory action on NaFCaFR-induced contractions. Similar inhibitions of the same type of contraction were displayed by aminoglycosides (neomycin, streptomycin, netilmycin, gentamycin and amikacin). These results suggest that in addition to their antagonistic action on nicotinic receptors in the frog rectus abdominis, aminoglycosides may exert stabilizing effects on some functional components contributing to contractions at the membrane.</p> No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 45 4 1991 A sheep survived for 48 days with the biventricular bypass type total artificial heart. 223 231 EN Kozo Ishino Taiji Murakami Hironobu Nakayama Makoto Yamada Tooru Morimoto Kunikazu Hisamochi Takashi Tanaka Yoshimasa Senoo Shigeru Teramoto Article 10.18926/AMO/32169 <p>A biventricular bypass type total artificial heart (BVB-TAH) utilizing two pusher-plate pumps was developed and implanted in a sheep for 48 days with excellent results. A Hall effect sensor was utilized to operate each pump independently with a full stroke at variable rates (VR). With this system, the animal's hemodynamics was kept physiologically, and all metabolic parameters except hemoglobin and hematocrit returned to normal three weeks after implantation. However, signs of infection appeared on the forty-second day, and consequently the animal fell into a state of shock. Even at that time the BVB-TAH maintained circulation by increasing pumping rate automatically. On the forty-eighth day, the animal could not stand and suffered from anuria; the experiment was then terminated after 1,140 h pumping. At autopsy, there was an enlarged heart with an atrophic change, 1,900 ml of pleural effusion, and 3,100ml of ascites fluid. Blood culture taken on the forty-seventh day yielded Acinetobacter calcoaceticus. The BVB-TAH operated in an independent VR mode maintained entire circulation, and has a capability of substituting the native heart function in any situation.</p> No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 52 5 1998 Evaluation of wheelchair cushions by means of pressure distribution mapping. 245 254 EN Hirosuke Takechi Akihiro Tokuhiro Article 10.18926/AMO/31321 <p>We studied the seated buttock pressure distribution in six paraplegic patients by means of computerized pressure mapping. They were all male and their age ranged from 18 to 48 years old. Their level of paralysis varied from Th5 to L1. Five kinds of wheelchair cushions were studied: an air cushion, a contour cushion, a polyurethane foam cushion, a Cubicushion (which is made of polyurethane foams) and a silicone gel cushion. A tactile sensor consisting of 2064 matrices was used for measuring the buttock pressure distribution and the data was analyzed on a personal computer. Peak pressures measured for each cushion were as follows (in descending order): the Cubicushion, the polyurethane foam cushion, the contour cushion, the silicone gel cushion, and the air cushion. The areas of total contact measured for each cushion were as follows (in descending order): the air cushion, the silicone gel cushion, the polyurethane foam cushion, the contour cushion and the Cubicushion. Based on these findings, we conclude that the most advantageous cushion is the air cushion or the silicone gel cushion. Likewise, we conclude that the Cubicushion is not practical for pressure sore prevention.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 1999 Automatic Micromanipulation System using Stereoscopic Microscope 327 331 EN Tetsuya Sano Hidekazu Nagahata Hideki Yamamoto <p>In this paper, we developed a visual feedback system that controls a micromanipulator so that a needle head may reach a target. The system consists of a stereoscopic microscope, a micromanipulator, two CCD cameras and a personal computer. The position of the target and the needle head under stereoscopic microscope are measured three dimensionally by using two CCD cameras which are set to eyepieces of the microscope. It is necessary that the image processing employed be fast so that the micromanipulation can be carried out at a realistic rate. The image processing time for detecting the target and the needle head is greatly reduced by using image compression </p> No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers Acta Medica Okayama 2 1996 Development of a tactile sensing flexible actuator 723 728 EN Yutaka Tanaka Akio Gofuku Yuji Fujino <p>The disadvantages of flexible artificial fingers have been improved. The finger is provided with the tactile sense by two types of sensors to detect when the finger tip touches an object and to estimate both the finger force and object size. The rigidity is enhanced by equipping the finger with a reinforcing material similar to that of human bone. A prototype robot hand with four fingers has been manufactured for experiments and mounted on an industrial articulated robot. The effectiveness of the improved robot hand finger was confirmed throughout experimental tests of grasping action</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 2003 Application of artificial pneumatic rubber muscles to a human friendly robot 2188 2193 EN Toshiro Noritsugu Daisuke Sasaki Masahiro Takaiwa <p>When robots work together with a human or contact with a human body directly in such as a medical welfare field, in order to avoid an accident from crash and so on, a flexibility is required for the robot. The purpose of this study is to realize a safe mechanism for a human-friendly robot. In this paper, the structure and the fundamental characteristics of a pneumatic rubber muscle and soft mechanism are described, and then the structure and the fundamental operation of the developed soft hand are shown. Finally, the shaking hands is discussed as an example of force communication tasks between a robot and a human. </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 3 1999 Micromanipulation using Stereoscopic Microscope 1066 1069 EN Tetsuya Sano Hideki Yamamoto <p>this paper, we developed a visual feedback system that controls a micromanipulator so that a needle head may reach a target. The system consists of a stereoscopic microscope, a micromanipulator, two CCD cameras and a personal computer, The positions of the target and the needle head under stereoscopic microscope are measured three dimensionally by using two CCD cameras which are set to eyepieces of the microscope. In order that the micromanipulation can be carried out at a realistic rate, it is necessary that the image processing is employed be fast. The image processing time for detecting the target and the needle head is greatly reduced by using image data compression.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 1991 High-speed processing for obtaining three-dimensional distance image and its application 365 370 EN Yutaka Tanaka Hideki Tsukaoka Hidetoshi Takeda Kazuo Honda Takaaki Sarai <p>A high-speed method of 3-D distance acquisition based on the triangulation principle is presented. This method uses conventional devices such as a CCD camera, a laser emitting semiconductor, and scanning mirrors; however, new circuits have been developed for detecting the position of spot image on the CCD. This development enables the high speed measurement and reduces the cost of the apparatus. Experiments showed that the apparatus and the method gave the practical measuring accuracy and speed, and it was found that the system is useful for image recognition. This method can easily display the stereoscopic image and cross-sectional figure of the object body. The method of real time processing has also been developed with the view to apply the device to the range finders for robots and blind persons</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 4 2001 Perception-action rule acquisition by coevolutionary fuzzy classifier system 2405 2410 EN Hisashi Handa Takashi Noda Tadataka Konishi Mitsuru Baba Osamu Katai <p>Recently, many researchers have studied the techniques in applying a fuzzy classifier system (FCS) to control mobile robots, since the FCS can easily treat continuous inputs, such as sensors and images by using a fuzzy number. By using the FCS, however, only reflective rules are acquired. Thus, in the proposed approach, an additional genetic algorithm is incorporated in order to search for strategic knowledge, i.e., the sequence of effective activated rules in the FCS. Therefore, the proposed method consists of two modules: an ordinal FCS and the genetic algorithm. Computational experiments based on WEBOTS, one of the Khepera robot simulators, confirm the effectiveness of the proposed method</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2000 Improvement of odometry for omnidirectional vehicle using optical flow information 468 473 EN Keiji Nagatani Satoshi Tachibana Makoto Sofue Yutaka Tanaka <p>Our research goal is to realize a robust navigation in indoor and outdoor environment for autonomous vehicle. An omnidirectional vehicle driven by four Mecanum wheels was chosen for our research platform. Mecanum wheel has 16 tilted rollers (45 degrees against the direction of wheel rotation) around the wheel, so the vehicle moves omnidirectionally by controlling these wheels independently. However, it has a disadvantage in odometry because of wheel slippage. Particularly, when the robot moves laterally, same wheels' rotations generate different traveling distance depending on friction of ground surface. To cope with the problem, we estimate robot's position by detecting optical flow of ground image using vision sensor (visual dead-reckoning). The estimation method is inaccurate comparing with odometry, but it is independent from friction of ground surface. Therefore, the estimated vehicle position can be improved by fusing odometry and visual dead-reckoning based on maximum likelihood technique. This paper describes an odometry method and a visual dead-reckoning method for omnidirectional vehicle, and fusion technique to improve the estimated position of the vehicle. Finally, experimental results support above technique </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 1995 Visual servoing with nonlinear observer 484 489 EN Koichi Hashimoto Hidenori Kimura <p>Visual servo system is a robot control system which incorporates the vision sensor in the feedback loop. Since the robot controller is also in the visual servo loop, compensation of the robot dynamics is important for high speed tasks. Moreover estimation of the object motion is necessary for real time tracking because the visual information includes considerable delay. This paper proposes a nonlinear model-based controller and a nonlinear observer for visual servoing. The observer estimates the object motion and the nonlinear controller makes the closed loop system asymptotically stable based on the estimated object motion. The effectiveness of the observer-based controller is verified by simulations and experiments on a two link planar direct drive robot</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1 1999 Visual servoing with linearized observer 263 268 EN Koichi Hashimoto Toshiro Noritsugu <p>One of the most important problems in feature-based visual servoing is the slow sampling rate and the delay of the camera that can make the closed loop system oscillative or unstable easily. In the paper, a linearized observer that estimates the object velocity and updates the visual information with the joint sampling rate is proposed. Stability of the observer-based control system and effectiveness of the observer are verified by experiments on a PUMA 560 robot</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 1998 A visual feedback system for micromanipulation with stereoscopic microscope 1127 1132 EN Tetsuya Sano Hidekaz Nagahata Hiroshi Endo Tetsuhiro Sumimoto Takeshi Kunishi Hideki Yamamoto <p>A stereoscopic microscope is widely used in a micromanipulation such as to operate genes and to inspect integration circuits. As in these tasks the micromanipulation is handled and makes too heavy burden to operators, it is desirable to perform the micromanipulation automatically. In this paper, we propose a visual feedback system for micromanipulation with stereoscopic microscope. This system takes less time to control the manipulator by reducing searching area to detect an object </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 4 2000 Enlargement of stable region in visual servo 3927 3932 EN Koichi Hashimoto Toshiro Noritsugu <p>Proposes a potential switching scheme that enlarges the stable region of feature-based visual servoing. Potential is defined as the norm of an image feature error and the stable region is a downward convex region of the potential surface that includes a reference position. The proposed scheme generates relay images that interpolate initial and reference image features and artificial potential is defined by using relay images. The artificial potentials are patched around the reference point of the original potential to enlarge the stable region. Simulations with simplified configuration and experiments on a 6 DOF robot show the validity of the proposed control scheme</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2001 Sensor based navigation for car-like mobile robots using generalized Voronoi graph 1017 1022 EN Keiji Nagatani Yosuke Iwai Yutaka Tanaka <p>Our research objective is to realize sensor based navigation by car-like mobile robots. The generalized Voronoi graph (GVG) can describe a mobile robot's path for sensor based navigation from the point of view of completeness and safety. However, it is impossible to apply the path to a car-like mobile robot directly, because limitation of the minimum turning radius prevents following the non-smooth GVG. To solve the problem, we propose a local smooth path planning algorithm for car-like mobile robots. Basically, an initial path is generated by a conventional path planning algorithm using GVG theory, and it is deformed smoothly to enable car-like robots' following by maximizing an evaluation function proposed in the paper. The key topics are: definition of our evaluation function; and how to modify the GVG. We introduce a local smooth path planning algorithm based on the GVG, and explain a detail of the evaluation function. Simulation results support validity of the algorithm </p> No potential conflict of interest relevant to this article was reported.

岡山大学環境管理センター Acta Medica Okayama 0917-1533 25 2003 誘電率計測法による地盤の汚染度及び有効間隙率の測定方法に関する基礎的研究 19 24 EN Makoto Nishigaki Mitsuru Komatsu Man-il Kim For evaluating subsurface contamination, sampling method (boring) is commonly used, but this method cannot monitor the change of in-situ contamination and concentration with respect to time. The purpose of this study is to develop a measuring system for subsurface contamination in which a so-called FDR (Frequency Domain Refiectometry) and FDR-V (with Vector network analyzer) system was employed to measure the salinity and oil contaminant. This FDR and FDR-V method is a coaxial probe method, which allows the measurement of the dielectric. The experimental study indicates the possibility in measuring both the contaminant concentration and volumetric moisture content. In addition, the method for obtaining the effective porosity using this equipment was shown. Concretely, the sensor was inserted in the ground, and the liquid in which the dielectric constant differed on the water in the circumference was injected, and the method for obtaining the effective porosity from the change of the dielectric constant was proposed. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 122 1 2010 DNA 損傷センサーATMキナーゼとChk2はＣ型肝炎ウイルスのRNA複製に必要である 9 16 EN Yasuo Ariumi Misao Kuroki Hiromichi Dansako Kenichi Abe Masanori Ikeda Takaji Wakita Nobuyuki Kato No potential conflict of interest relevant to this article was reported.

日本分析化学会 Acta Medica Okayama 0525-1931 42 7 1993 微分光度滴定法による水溶液での陰イオン界面活性剤の定量 T105 T111 EN Shoji Motomizu Yunhua Gao Shinsuke Ishihara Kouji Uemura Kazuyuki Daito Tatsushi Wakisaka 微分光度滴定装置を用いて,水溶液での陰イオン界面活性剤を定量する方法について検討した.滴定終点決定の指示薬系としては,酸性染料のテトラブロモフェノールフタレインエチルエステル(TBPE)と非イオン界面活性剤のTriton X-100(TX-100)の混合溶液を用いた.TBPEは非イオン界面活性剤の存在下で,酸性では黄色となり可溶化しているが,滴定剤の第四級アンモニウムイオンと反応するとイオン会合体を形成し,解離型(TBPE-)の青色(λ(max)=610nm)となる.滴定剤には第四級アンモニウム塩のジステアリルジメチルアンモニウム・クロリド(DSDMA(+)・Cl(-))を用いた.本滴定法で10(-6)〜10(-3)Mの濃度範囲の陰イオン界面活性剤が定量できる.実際試料の定量結果はオキシエチレン基を持つもの以外の試料において,JIS滴定法(JIS K 3362)及びエチルバイオレット抽出吸光光度法(JIS K 0101)とよく一致した. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254　 99 1 2010 食肉の品質特性の解析と応用 85 95 EN Masatoshi Izumimoto The quality of food has always been evaluated by the five senses of human. It is possible for a sensory evaluation with no special device for anyone anywhere anytime. The evaluation is only result information, but it is not possible by evaluation to obtain cause information for quality control. Among evaluation information by the five senses for the food, sight has been developed most as the scientific method. The next development is texture, and then taste, odor and hearing are just developing. Deterioration of food becomes economic loss then results in environment load, so quality control is important. Instrumental analyses of the qualities of taste and flavor have not been very developed. Actually, the sensory evaluations for sight, odor, taste, hearing and texture examination are performed by the senses, but it is only evaluation. The evaluation is results information and there is a limit to know cause information. Sensory evaluation is subjective, vague and may become arbitrary. Quality control is difficult by non experts with knowledge and experience. Therefore, cause information for scientific quality control was integrated with result information as evaluation. Objective cause information for the quality control is obtained by computer connected with the instrument having sensory sensor. In this report, first, differences of evaluation and quality control for meat quality are explained. Successively, automatic analysis of characteristics of color quality and quality control, human interface of texture quality, inhibition of cells DNA damage by heme protein, the method of color development without nitrous acid and inhibition with fig protease against ACE, angiotensin-I converting enzyme were described. No potential conflict of interest relevant to this article was reported.

IEEE SMC Hiroshima Chapter Acta Medica Okayama 1883-3977 2009 1 2009 Basic study on effectiveness of tactile interface for warning presentation in driving environment 242 247 EN Atsuo Murata Kohki Tanaka Makoto Moriwaka The aim of this study was to get insight into the development of tactile interface for automobile warning system. In other words, it was investigated whether the important driving information in the right and left peripheral visual fields can be recognized faster using tactile warning system as compared with auditory warning system. The participants were required to simultaneously carry out a tracking task (main task), a switch pressing task such as selection of light-on function, and a judgment task of important information which randomly appeared to the right or left peripheral visual field. The tracking error, the number of lane deviation, the percentage correct of switch pressing, and the response time to right and left peripheral stimulus were measured. It was examined how age, the modality of alarm presentation (no alarm, auditory, and tactile), the addition of direction in alarm presentation, and the existence of disturbance sound, and the location of tactile sensor (steering or foot) affected the measures above. The young adults performed better than older adults. The response time was not affected by the modality of alarm presentation, and the disturbance sound. The addition of direction of alarm presentation affected the performance. The tactile sensor attached to the foot led to faster response than that attached to the steering wheel. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 86 1-2 1974 隔膜型ポーラログラフ電極による人血液カタラーゼの定量的スクリーニングテスト法について 53 59 EN Syozo Sumida Acatalasemia is the homozygote of an abnormal gene which is considered to be involved in the vital catalase synthesis of man, as discovered by Takahara in 1946. The hypocatalasemia which is a heterozygote of this abnormal gene, since its blood catalase activity is only about one half that of normal persons, has a characteristic of being accurately detected by the biochemical methods. In addition, it is of a great importance in the sense of gentics to determine its frequency by the cases of hypocatalasemia. As for the screening tests of this hypocatalasemia the titration with potassium permanganate has been mostly used, but the author devised a new method of determining catalase activities of the subjects by measuring the amount of oxygen gas produced from H(2)O(2) by the action of catalase, using the polarographic sensor. This method, compared with the available ones has a great advantage in that its accuracy, the ease of examinations and possible simultaneous screening tests with quantiative analysis are possible. Furthermore, this method is a superior one that it is easy to transport the test apparatus and conduct field examinations. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 91 7-8 1979 急性頭蓋内圧亢進時の脳循環動態に関する研究 第1編 光電法を応用した局所脳血液量測定法の開発 861 880 EN Hideyuki Kuyama The cerebral blood volume (CBV) is an important parameter of cerebral hemodynamics. However, measurement of CBV has been difficult. We have devised a photoelectric method for measurement of regional CBV. The sensor of the apparatus was made of three components; a microlamp, a photodiode to which an infra-red filter was attached, and a polyethylene balloon, or polyethylene catheter with its tip open for intracranial pressure (ICP) measurement. These were pasted with silicon rubber. The sensor was applied to the brain surface to measure the intensity of the optical absorption (OA) of hemoglobin in the brain tissue. OA remained nearly constant despite various alterations in cerebral blood flow (CBF), brain tissue pressure, and water content of the brain. Both OA and ICP increased during vasodilatation induced by CO(2) inhalation, compression of the jugular veins, or intravenous injection of Papaverine hydrochloride. Both decreased during vasoconstriction induced by hyperventilation or severe arterial hypotension. These results suggest that OA reflects changes of CBV. The disadvantages of this method are that the absolute CBV and the CBV in the deeper brain tissues can not be measured and that the operative field has to be kept dark. However, this method has several advantages; (1) Regional CBV is continuously measured without radionuclide or other specific indicators. (2) This method does not require a skilled technique. (3) The cerebral transit time can be measured by injection of saline or other indicators into the right brachial artery. (4) This device can also measure ICP. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 91 3-4 1979 脳浮腫における局所頭蓋内圧差発生に関する実験的研究 437 452 EN Kazuhiko Ninomiya The present studies were designed to determine whether significant pressure differences between hemispheres occur in response to cold-induced cerebral edema and if so, their response to induced high intracranial pressure. The experiments were carried out on 35 adult mongrel dogs weighing between 8 to 12kg under intraperitoneal pentobarbital anesthesia. A cold-induced edema was produced at the left frontal lobe by placing a metallic cylinder filled with liquid nitrogen on the exposed dura mater for 5 minutes. Subdural pressures were recorded continuously for 12 hours from the subdural spaces over the left parietal lobe adjacent to the cold injury and the right parietal lobe remote to the injury, using microballoons or Fiber-optic pressure switch sensors through burr holes. Cisterns magna pressure was also continuously measured with a needle inserted into the cisterna magna by percutaneous puncture. In addition, during progressing cerebral edema, intracranial pressure was investigated after the injection of saline solution into the cisterna magna at 1000 mm hydrostatic pressure at 3, 6 and 12 hours after cold injury. Three hours after cold injury, the subdural pressure of the left injured hemisphere was higher than that of the right non-injured one. About 6-9 hours following injury, pressure differences between injured and non-injured hemispheres showed maximal values ranging from 40 to 160 mm H(2)O (3-11.8 mmHg). Intracranial pressure had increased markedly. by 9 hours after cold injury, at which time such pressure differences decreased gradually. In the late stage of edema, however, intracranial pressure was distributed equally throughout the entire brain, so that pressure differences had disappeared. The changes in intracranial pressure after injection of saline revealed a biphasic pattern about 3 hours after injury as compared with the normal. At 12 hours, elevated intracranial pressure after injection did not return to the previous resting level. These phenomina suggest that the initial steep drop represented intracranial volumetric compensation by the intracranial and spinal coverings and venous system in the central nervous system, and that the late gentle slope represented impairment of cerebrospinal fluid absorption. These results indicated at least two possible explanations for the origin of pressure differences : 1) reduction of the pressure compensating capacity of the injured swollen hemisphere blocking the free communication of cerebrospinal fluid and collapsed venous system, 2) delayed transmission of the elevated pressure from the lesion to the noninjured hemisphere because of local change in viscoelasticity. Accordingly, changes in pressure differences as well as the height of intracranial pressure would play a major role in the pathophysiology of an expanding lesion. No potential conflict of interest relevant to this article was reported.

Faculty of Engineering, Okayama University Acta Medica Okayama 0475-0071 27 1 1992 Process Fault Diagnosis using Neural Networks and Fault Tree Analysis Information 33 44 EN Yukiyasu Shimada Kazuhiko Suzuki Hayatoshi Sayama 10.18926/15391 Neural nets have recently become the focus of much attention, largely because of their wide range of complex and nonlinear problems. This paper presents a new integrated approach using neural networks for diagnosing process failures. The fault propagation in process is modeled by causal relationships from the fault tree and its minimal cut sets. The measurement patterns required for training and testing the neural network were obtained from fault propagation model. The network is able to diagnose even in the presence of malfunction of certain sensors. We demonstrate via a nitric acid cooler process how the neural network can learn and successfully diagnose the faults. No potential conflict of interest relevant to this article was reported.

Faculty of Engineering, Okayama University Acta Medica Okayama 0475-0071 30 1 1995 Principle of Biodynamic Analysis Using Human Limb Electrical Impedance 19 24 EN Takao Nakamura Yoshitake Yamamoto 10.18926/15369 This paper describes a new measurement method and principle of detection of biodynamics using bioelectrical impedance method based on four-electrode technique with sinusoidal constant current. This method uses a human body itself as a part of the sensor. First, we show a bioelectrical impedance measuring device and the change of bioelectrical resistance is measured in human movement. Second, we proposes a principle of detection of biodynamics based on correspondence of magnitude, form and stability of movement to impedance waveform. Hence we can use this method for the judgement of sports skill using the impedance characteristics. No potential conflict of interest relevant to this article was reported.

岡山大学医学部保健学科 Acta Medica Okayama 1345-0948 16 1 2005 トノメトリ法による血圧脈波計測原理解析のための血管断面構造モデルに求められる要件 9 20 EN Tomoki Kitawaki Hisao Oka 10.18926/15179 生体内の血圧脈波を非侵襲的に計測する手法として,｢トノメトリ法｣が知られており,近年,この計測手法を用いて得られた血圧脈波波形から,動脈硬化などの循環器系疾患のスクリーニングや予防診断に役立てようという動きが活発である｡しかしながら,組織内の血管を圧迫した場合の血管の変形挙動については,十分な解析は行われていない｡そこで本研究では,生体中のトノメトリ状態を解析可能な数値解析モデルを構築することを目的とした｡この結果, トノメトリ法による血圧脈波計測の原理解析を行うための血管断面構造の応力解析モデルには,以下の要件が求められることが明らかとなった｡・センサ部と皮膚表面はそれぞれ独立な要素としてモデル化し,これらの接触部においては摩擦を考慮しなければならない｡・応力の定量的な解析を行うためには,素材の非線形的な機械的特性を考慮する必要がある｡さらに,実験結果と計算結果を一致させるためには,初期形状を正確にモデル化することが必要であることがわかった｡ No potential conflict of interest relevant to this article was reported.

岡山大学医学部附属病院三朝分院 Acta Medica Okayama 0918-7839 65 1994 気管支喘息および慢性関節リウマチにおける気道抵抗(sRaw)および気道コンダクタンス(sGaw)に対するサルブタモールまたはクロモリン吸入の影響 87 95 EN Satoshi Yokota Hikaru Kitani Takashi Mifune Kazuhiro Kajimoto Fumihiro Mitsunobu Itiro Takata Yoshiro Tanizaki Shinya Tada Mine Harada 10.18926/15159 サルブタモールまたはdisodium cromoglycate(クロモリン)吸入液を,気管支喘息(以下BA)6例,慢性関節リウマチ(以下RA)7例,正常対照5例に吸入させ,吸入前および吸入後約30分に,気道抵抗(sRaw)と気道コンダクタンス(sGaw)を,定容積型体プレチスモグラフ(Sensor Medics Corporation, Anaheim, California, made in U.S.A.)を用いて測定した｡吸入前の値をsGawで比較すると,BAはRAや正常対照に比べ有意に閉塞の程度が強く,RAと正常対照の間では有意な差はなかった｡サルブタモール吸入の場合,BAでは吸入後にsRawおよびsGawの有意な改善(P<0.01)がみられ,それらの改善率(%)は,RAや正常対照と比べて有意に高く(P<0.01),RAと正常対照の間では改善率の有意な差は認めなかった｡クロモリン吸入の場合,いずれの群においても,sRawおよびsGawの吸入後の変化に有意差はみられなかったが,BAにおいて,sRawの改善率(%)はRAと正常対照に対して,またsGawの改善率(%)は正常対照に対して有意に高く(P<0.05),RAと正常対照の間では,sRaw,sGaw共に改善率(%)の明らかな差はみられなかった｡ No potential conflict of interest relevant to this article was reported.

岡山大学医学部附属病院三朝分院 Acta Medica Okayama 0918-7839 66 1995 気管支喘息における抗喘息薬吸入効果の体プレチスモグラフによる評価 49 56 EN Satoshi Yokota Takashi Mifune Kazuhiro Kajimoto Fumihiro Mitsunobu Yoshiro Tanizaki 10.18926/15124 サルブタモール,クロモグリク酸ナトリウム(クロモリン)吸入液を,気管支喘息(以下BA)11例,肺病変のない対照群9例に吸入させ,吸入前および吸入後30分に,sRaw(specific airway resistance)とsGaw(specific airway conductance)を,定容積型体プレチスモグラフ(Sensor Medics Corporation, Anaheim, California, U.S.A.)を用いて測定した。サルブタモールの場合,BAでは吸入後に有意な改善(p<0.01)を認め,対照群でも有意な変化(p<0.05)があったが,改善率(%)はBA が対照群に比べて有意に高かった(p<0.01)｡クロモリンの場合,吸入前後での比較では有意差は認めなかったが,吸入後にBAでは改善,対照群では悪化する傾向があり,改善率(%)はBA が対照群に比べて有意に高値(p<0.01)であった｡ No potential conflict of interest relevant to this article was reported.

岡山大学理学部地球科学教室 Acta Medica Okayama 1340-7414 7 1 2000 船舶を用いた海面乱流フラックスの自動観測 1 14 EN Satoshi Takahashi Osamu Tsukamoto Hiroshi Ishida Kunio Yoneyama 10.18926/ESR/13891 Sea surface eddy fluxes were evaluated with the eddy correlation method including ship motion correction for the wind vector components. Previous ship motion correction algorithm was revised as a simple scheme setting a motion sensor at the same place with the sonic anemometer. This revised eddy flux system was mounted as a routine continuous measurement system on the R/V 'Mirai' of Japan Marine Science and Technology Center. The first cruise was conducted at the tropical weatern Pacific in June 2000. Continuous sea surface fluxes were obtained and the data quality was checked with some parameters. This system is planned to be developed as a automated data processing system including ship motion correction and real-time flux evaluation system. These eddy fluxes can be integrated with the bulk fluxes and radiation fluxes to understand sea surface heat balance over the global ocean. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 116 1 2004 神経シナプスにおけるエンドサイトーシス機能タンパク質‐膜リン脂質 相互作用機序の人工脂質膜を用いた解析法―岡山大学医学賞（新見賞）を受賞して― 1 8 EN No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 117 2 2005 ペンシル型CCD 生体顕微鏡システムを用いたin vivo肺微小循環と肺胞呼吸の同時可視化 119 125 EN Taro Morimoto We succeeded in visualizing in vivo perialveolar microcirculation and individual alveolar respiration in rats,by our high resolution intravital charge-coupled device videomicroscopy system. To elucidate the relevance and usefullness of our methods, we investigated their behavior 1) under control conditions, 2) during increased tidal volumes (TV), 3)during positive-end expiratory pressure (PEEP) application, and 4)during exposure to hypoxia. We recognized a sheet-like flow pattern in capillaries, and observed semi-collapsed capillaries at end-inspiration while flow continued.The latter indicate existence of“vascular waterfall phenomenon”.When TV was increased from 2.5 to 5ml, the alveolar size was increased from 30±10 to 65±18μm (n＝21, p＜0.05), and the red blood cell velocities in perialveolar capillary were significantly decreased from 910±210 to 290±140μm/sec (n＝21,p＜0.05). Following PEEP application with TV of 5ml,the alveolar diameter was increased even more to 80±20μm (n＝12,p＜0.05)and the flows of microvessels stopped temporarily at end-inspiration.We also visualized that precapillary arterioles clearly constricted from 34±6 to 28±6μm in response to hypoxia (n＝9, p＜0.05). In conclusion, the intravital pencil lens-probe videomicroscopy can be a powerful tool for in vivo observation of perialveolar microcirculation and alveolar respiration under important physiological conditions such as changing TV, application of PEEP, and exposure to hypoxia. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 117 3 2006 シナプス小胞エンドサイトーシスの制御機構に関する研究 193 198 EN No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 116 3 2005 新しい核内受容体 Pregnane X Receptor の生殖生理における役割―岡山大学医学賞（林原賞）を受賞して― 215 220 EN No potential conflict of interest relevant to this article was reported.

岡山大学環境理工学部 Acta Medica Okayama 1341-9099 9 1 2004 傾度法と渦相関法で測定した二酸化炭素フラックスの比較 69 73 EN Sachiko Inohara Toru Iwata Eiji Ohtaki 10.18926/fest/11459 To elucidate the seasonal and inter-annual variation of CO(2) exchanges between the atmosphere and cultivated field in Japan, the CO(2) flux has been measured by the eddy correlation technique at the experimental farm of Agricultural Faculty, Okayama University since December in 1998. The CO(2) sensor, however, does not work under rainy conditions. The improved aerodynamic technique was developed and used to cover CO(2) flux data which were not collected. This technique gives reasonable CO(2) fluxes even in rainy days. The reliability of the technique was also confirmed by comparing CO(2) fluxes with those measured by the eddy correlation technique using data in fine weather conditions. No potential conflict of interest relevant to this article was reported.

岡山大学資源生物科学研究所 Acta Medica Okayama 0916-930X 1 2 1993 群落生物環境反応測定装置によるオオムギ群落における試験観測結果について 137 146 EN Toshihiko Maitani Yoshiaki Kashiwagi A system designed to measure the vegetation response to environment was constructed on the basis of the eddy correlation method.It consisted of two sets of a small rapid response sensors; three dimensional sonic anemometer thermometers and infrared CO2-humidity fluctuation meters,and a personal computer for data acquisition. Field tests of the system were made over a barley field in April and May,1990.The turbulent fluxes obtained by two sets of flux measuring system mounted at the same height were in fair agreement. The turbulent fluxes(momentum,sensible heat,latent heat and carbon dioxide) measured at two height wihtin and above plant cannopies and their differences showed realistic diurnal variations.The direction and magnitude of each flux varied depending on the srength or distribution of source and sink within plant canopies. These findings confirmed that this measureing system is promising for quantitative estimate of vegetation response such as transpiration, photosynthesis and respiration in certain canopy layers to environmental variations. No potential conflict of interest relevant to this article was reported.

岡山大学教育学部 Acta Medica Okayama 0471-4008 132 2006 AGVを適用した工場モデルの教材化に関する研究 29 37 EN Kazumasa Ohashi 10.18926/bgeou/10938 Recently, the factory automation controlled by computer has greater impact on manufacturing development. The factory model pursuing both efficiency and flexibility of manufacturing is proposed in this paper. Automated Guided Vehicle has an important role for technological improvement of factory model. It can transport many parts to each station consisting of NC machines. In order to learn the operating management of the proposed factory automation, a new teaching material is needed for school education. Consequently, a prototype of factory model with AGV routing layout is constructed in this paper. In this model, AGV controlled by some sensors is assembled with LEGO Mindstorms. Finally, an example is given to show the practical use of the proposed factory model for the manufacturing education. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 91 1 2002 Ｌ−グルタミン酸オキシダーゼを用いたグルタミン酸センサーの開発及びＧＯＴ/ＧＰＴセンシングへの応用 15 22 EN Jiro Arima Takashi Tamura Hiroaki Shinohara Hitoshi Kusakabe Hidehiko Tanaka Kenji Inagaki L-Glutamate measurement and GOT/GPT assay was successful by H2O2 measurement using the L-glutamate oxidase with 4-aminoantipyrine / phenol method. But, in examination of oxigen electrode, immobilized L-glutamate oxidase at the cellulose to L-glutamate and GOT-GPT sensor, Lpglutamate measurement was used for the amperometric determination with non-fixed enzyme. On examination of electron mediator, response for L-glutamate was observed with each of the compounds ferricyane, ferrocene-COOH, ferrocene-MeOH, and benzoquinone. L-Glutamate was measured by carbon printed tip electrode the L-glutamate oxidase and ferricyane based on the principle of chronoamperometry. A linear calibration graph was obtained between 1mM and 30mM. These results suggest that L-glutamate oxidase is able to utilize to L-glutamate sensor, and that there is a strong possibility to put this sensor to sensing for GOT/GPT activity. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1999 Evaluation of Wheelchair Cushions by Means of Pressure Distribution Mapping EN Hirosuke Takechi We studied the seated buttock pressure distribution in six paraplegic patients by means of computerized pressure mapping. They were all male and their age ranged from 18 to 48 years old. Their level of paralysis varied from Th5 to L1. Five kinds of wheelchair cushions were studied: an air cushion, a contour cushion, a polyurethane foam cushion, a Cubicushion (which is made of polyurethane foams) and a silicone gel cushion. A tactile sensor consisting of 2064 matrices was used for measuring the buttock pressure distribution and the data was analyzed on a personal computer. Peak pressures measured for each cushion were as follows (in descending order): the Cubicushion, the polyurethane foam cushion, the contour cushion, the silicone gel cushion, and the air cushion. The areas of total contact measured for each cushion were as follows (in descending order): the air cushion, the silicone gel cushion, the polyurethane foam cushion, the contour cushion and the Cubicushion. Based on these findings, we conclude that the most advantageous cushion is the air cushion or the silicone gel cushion. Likewise, we conclude that the Cubicushion is not practical for pressure sore prevention. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 73 1 1989 Detecting Fruit by Visual Feedback on Hand-Eye System (�U) : Fruit Detecting Simulation by Computer 75 78 EN Naoshi Kondo Shunzo Endo The computer simulation of detecting fruit by visual feedback on hand-eye system was done in order to investigate detecting accuracy under the various conditions. From the result, it was obtained as follows : 1. The smaller the distance from the visual sensor to the fruit was smaller, the error by visual feedback became smaller proportionally. 2. The error depended on the fruit diameter. 3. The bigger the picture element number was, the smaller the scattering. 4. The bigger the manipulator speed was, the bigger the picture element number recognizing fruit became, and the error became bigger. 5. It was not suitable that visual feedback on hand-eye system was independently used for detecting fruit whose diameter had the scattering fairly. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 72 1 1988 Detecting Fruit by Visual Feedback on Hand-Eye System (I) : Fruit Detecting Experiment Using Anthropomorphic Type Manipulator 69 76 EN Naoshi Kondo A visual sensor which could recognize fruits was made in order to develop the sight sense of the fruit harvesting robot. This visual sensor was attached to an anthropomorphic type manipulator, and a fruit detecting experiment using a method of visual feedback was done. The results were obtained as follows ; 　It was observed that the hand was able to grip the orange balls which positioned at 30 cm in front of the visual sensor. It was given as defects that the error depended on the fruit diameter arose, number of the image input was big, and so on. It was considered that this method was more advantageous to telescopic type manipulator than anthropomorphic type manipulator. No potential conflict of interest relevant to this article was reported.