Communication with others plays an important role in human social interaction and information exchange in modern society. However, some individuals have difficulty in communicating due to dysarthria. Therefore, it is necessary to develop effective diagnostic techniques for early treatment of the dysarthria. In the present study, we propose a mobile device-based methodology that enables to automatically classify dysarthria type. The light-weight CNN model was trained by using the open audio dataset of Korean patients with dysarthria. The trained CNN model can successfully classify dysarthria into related subtype disease with 78.8%~96.6% accuracy. In addition, the user-friendly mobile application was also developed based on the trained CNN model. Users can easily record their voices according to the selected inspection type (e.g. word, sentence, paragraph, and semi-free speech) and evaluate the recorded voice data through their mobile device and the developed mobile application. This proposed technique would be helpful for personal management of dysarthria and decision making in clinic.

The purpose of this study is to conduct a summative evaluation of the usability of a general-purpose ventilator to determine whether it can be used for its intended purpose in the intended environment by the intended user and to find possible errors in use. The importance of ventilators has increased due to the accelerated aging of the population and the impact of the pandemic. In addition, patients who require ventilators are often in critical condition, so even a small error in use can be fatal. Therefore, it is important to ensure that the ventilator has sufficient stability and can be used satisfactorily without inconvenience to the user. In this study, we conducted a usability test with 17 respiratory nurses with more than 3 years of experience using the ventilator. We analyzed the task success rate, satisfaction, and opinions of the intended users while going through a total of 17 scenarios. Satisfaction was captured through an ASQ questionnaire and subjective opinions were captured through a detailed opinion questionnaire. The results showed a high level of satisfaction with an average score of 6.3 for the use scenarios. Evaluators expressed satisfaction with the overall visibility and versatility of the features, but noted that improvements were needed for calibration tasks with low task success rates. As the calibration method is different from other equipment, it was suggested that specific explanations of the calibration method and the picture that appears when calibrating are needed, and that if relevant training is provided, the equipment can be used without problems. If the usability evaluation is not limited to securing efficiency and satisfaction from the intended users, but also continuously receives feedback from users to prepare for use in emergency environments such as pandemic situations, it will be very helpful to seize opportunities such as emergency authorization in future situations, and ultimately contribute to patient safety by reducing use errors.

Extracellular vesicles (EVs) are nano-sized lipid bilayer vesicles released by cells. EVs act as messengers for cell-to-cell communication. Inside, it contains various substances that show biological activity, such as proteins, lipids, nucleic acids, and metabolites. The study of EVs extracted from terrestrial organisms and stem cells on inflammatory environments and tissue regeneration have been actively conducted. However, marine organisms-derived EVs are limited. Therefore, we have extracted EVs from sea urchins belonging to the Echinoderm group with their excellent regenerative ability. First, we extracted extracellular matrix (ECM) from sea urchin gonads treated with hypotonic buffer, followed by collagenase treatment, and filtration to collect ECM-bounded EVs. The size of sea urchin gonad-derived EVs (UGEVs) is about 20-100 nm and has a round shape. The protein content was higher after EVs burst than before, which is evidence that proteins are contained inside. In addition, proteins of various sizes are distributed inside. PKH-26 was combined with UGEVs, which means that UGEVs have a lipid membrane. PHK-26-labeled UGEVs were successfully uptaken by cells. UGEVs can be confirmed to have the same characteristics as traditional EVs. Finally, it was confirmed that Schwann cells were not toxic by increasing proliferation after treatment.

Functional brain imaging techniques have been used to diagnose psychiatric disorders such as dementia, depression, and autism. Recently, these techniques have also been actively used to study hearing loss. The present study reviewed the application of the functional brain imaging techniques in auditory research, especially those focusing on hearing loss, over the past decade. EEG, fMRI, fNIRS, MEG, and PET have been utilized in auditory research, and the number of research studies using these techniques has been increasing. In particular, fMRI and EEG were the most frequently used technique in auditory research. EEG studies mostly used event-related designs to analyze the direct relationship between stimulus and the related response, and in fMRI studies, resting-state functional connectivity and block designs were utilized to analyze alterations in brain functionality in hearing-related areas. In terms of age, while studies involving children mainly focused on congenital and pre- and post-lingual hearing loss to analyze developmental characteristics with and without hearing loss, those involving adults focused on age-related hearing loss to investigate changes in the characteristics of the brain based on the presence of hearing loss and the use of a hearing device. Overall, ranging from EEG to PET, various functional brain imaging techniques have been used in auditory research, but it is difficult to perform a comprehensive analysis due to the lack of consistency in experimental designs, analysis methods, and participant characteristics. Thus, it is necessary to develop standardized research protocols to obtain high-quality clinical and research evidence.

In this study, we explored the possibility of using sympathetic skin response (SSR), a type of electrodermal activity (EDA), as a method of evaluating a subject's responsiveness to physical or psychological stimulation. To provide physical and psychological stimulation, walking on an acupressure plate and a roller coaster virtual reality experience wearing an HMD (head mounted display) were used. Walking on an acupressure plate significantly increased the SSR signal compared to walking on the bare floor. Additionally, it was observed that the SSR response significantly increased while the subject was wearing an HMD and experiencing a roller coaster compared to the resting state of sitting on a chair. The SSR response to physical or psychological stimulation increased in all subjects, but the degree of reactivity differed. These experimental results suggested that sympathetic skin response (SSR) is a useful tool as a biosignal that can be used to evaluate the human body's responsiveness to physical stimulation or psychological stimulation using virtual reality.

The prevalence of obesity and its complications is steadily increasing worldwide. It is essential to understand cellular level metabolism and microenvironment to treat diseases related to lipid metabolism. Mechanical loading can activate signaling pathway by stimulating cells, especially vibration loading known to inhibit adipogenesis, so it has been studied as a treatment for obesity. Also, vibration loading can affect the inside of the human body non-invasively. Another clue to reducing adipose tissue is browning, which means that white adipocytes changes to brown adipocyte. In this study, we design and developed a device that that can control cell-cell contact, and vibration simulation device. Using these two devices, we investigated responses of cells to vibration loading. Protein expression associated with browning and adipogenesis were analyzed. In conclusion, vibration loading can be transmitted through cell contact and loading applied to the cells can induce browning and inhibit adipogenesis of preadipocytes. These results suggest the possibility that vibrations could be a treatment for obesity.

Accurate measurement of blood pressure is essential for classifying an individual's disease, identifying blood pressure-related risks, and managing health. Due to the environmental and health hazards of mercury sphygmomanometers, automatic sphygmomanometers using the oscillometric method are widely used in hospitals as well as in general homes, and have established themselves as a practical standard sphygmomanometer. In this study, we developed a blood pressure simulator using an actuator that provides simulated pressure to an automatic blood pressure cuff. The developed blood pressure simulator adopts an arm-shaped cylindrical shape similar to the situation in which a person measures blood pressure with an automatic blood pressure monitor, and implements a method of transmitting pressure to the cuff using a pressure plate. Accuracy was evaluated through the mean and standard deviation of the difference with the commercialized blood pressure simulator BP PUMP 2, and reproducibility was confirmed using two automatic blood pressure monitors. The developed blood pressure simulator enables automatic blood pressure monitoring in a simple manner and also meets the evaluation standards for accuracy and reproducibility. In the future, as a standardized blood pressure simulator, it is expected to be of great help in evaluating and verifying the performance of automatic blood pressure monitors by supplementing precise hardware and software and building a blood pressure database.