Transdermal assessment of cortisol awakening response (CAR) by microneedle perforation technique was regarded. CAR is a prominent cortisol variation after awakening. Since it has been reported to associate with chronic or daily stress, CAR is assumed as a possible stress indication. However CAR determination by saliva has methodological disadvantages such as lower compliance of multiple specimen collection, bold estimation of total cortisol by discrete sampling time points, etc. We then introduced our developed transdermal interstitial fluid extraction technique, which was implemented by microneedle perforation technique, and investigated the validity of CAR determined by extracted interstitial fluid. Subjects, 10 healthy male, were instructed to collect their saliva at four time points after awakening at 6:00-7:00 and in the afternoon at 14:30-15:30. Besides, their interstitial fluid was collected by microneedle perforation technique on the same schedule. There found a significant positive correlation (r = 0.80, p <.01) between salivary CAR and that of interstitial fluid when it was adjusted by sodium ion concentration which was assumed as a calibrator of the extracted interstitial fluid. The proposed transdermal assessment of interstitial cortisol can be a useful methodology for CAR determination as the minimally invasive manner without any physical pain or bleeding.

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This study investigated whether salivary α-amylase activity (sAA) can be a useful index for evaluating sympathetic nervous system (SNS) function of autistic children in an educational setting. Subjects were 13 autistic children who were enrolled at a special needs education school. We measured the children's sAA activity and heart rate (HR) before and after their daily group and individual study sessions. The results showed that there was no significant difference in sAA or HR measured before and after each session. However, the variance of sAA values was significantly smaller after individual study sessions compared with that before the sessions. On the other hand, no significant difference was observed in the mean or variance of HR values between before and after each session. These results indicate that, in individual study sessions, teachers accurately recognize the arousal level of individual students and adjust the level of learning to meet each student's needs. Our findings also suggest that sAA values can be a useful indicator of functional changes in the SNS that are difficult to evaluate using HR values.

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To prevent various lifestyle-caused diseases, mental health care in daily life is one of the most important issues in recent years. This paper proposes quantitative analysis method of mental stress using heart rate variability (HRV). Specifically, we proposed the geometric figure analytical method of HRV in consideration for respiration sinus arrhythmia (RSA). Then mental stress is quantitatively evaluated by analyzing the geometric figures using pattern recognition. Experiments were repeated 72 times on 8 healthy male volunteers. It was suggested that the proposed method was successful for evaluating mental stress quantitatively. Finally, the result of long term monitoring experiment for a male volunteer, the proposed method was linked on his daily life situation.

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Human body communication is carried out along the body surface between the wearable equipment, and this technology can be potentially used for Body Area Networks. In this study, transmitter electrodes for human body communication were analyzed at 10MHz by FDTD method. This analysis has shown that the input impedance of the electrodes was dependent on the structure and dimensions of the electrodes. We derived approximation formulas to express these relationships between the input impedance and the design parameters. As an example, the electrodes for the wristwatch-sized (24 × 24mm) device were designed to have a matched input impedance of 50Ω without using impedance transformers or stubs. The electric field around the electrodes on the human arm under the impedance-matched condition was 10∼20 dB stronger than that of the mismatched condition, and the VSWR characteristics were less than 2 when the matched electrodes were used. The electric fields and currents on the body surface and inside the body, and those of the equipment, were less than the safety standards, when the received signal had sufficient strength for practical receivers. The transmission power of the antenna was less than that of Bluetooth devices.

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A wearable care support system has been developed for transmitting information of a wandering elderly person's location, environmental sounds and posture. The system consists of a wandering monitor device, a conventional desktop personal computer and a caregiver's mobile phone. The wandering monitor device, which is attached behind the neck of the person's shirt, is composed of a low transmitting power personal handy-phone system(PHS)module, a small microphone, an acceleration sensor and a one chip microcontroller. The wandering elderly person's location is identified by the PHS mobile phone company's base station via the PHS module. The caregiver sets the elderly person's safe resident area to the microcontroller. When the elderly person goes out of this area, the sensor automatically records the environmental sound around the wandering person, with the microphone, for 10 seconds. The PHS module sends the elderly person's location, the environmental sound and Z axis acceleration to the server computer. The server computer automatically informs the caregiver this information by e-mail. The caregiver can monitor the map of the wandering person's location and the sound via the Internet. The sound enables the presumption of a place and the situation of the elderly person.

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There are established anti-coagulation therapy and various rhythm and/or rate control therapies for atrial fibrillation treatment, although any therapies have unsolved problems. The efficacy of local brain cooling for epilepsy was previously reported. Atrial fibrillation is affected by various electrical abnormal activities on occurrence and maintenance, same as epilepsy. There were few reports of the investigation for cooling maneuver on the control of atrial fibrillation. We investigate the efficacy of local cooling maneuver for paroxysmal atrial fibrillation in the animal model. We use goats to experiment for local cooling maneuver for paroxysmal atrial fibrillation. We record the intra-cardiac electrogram by inserting a multi-electrode catheter which is placed for suitable right atrial site to distinguish the atrial electrogram from the ventricular one via juggler vein. We approach the beating heart by left thoracotomy in the anesthesized condition, and induce atrial fibrillation by giving direct current stimulation on left atrial surface. Induced atrial fibrillation rarely terminate spontaneously, then we utilize the Peltier device to cool left atrial surface after induced atrial fibrillation is sustained for 1 minute. Frequently we can observe termination of atrial fibrillation and restoration of sinus rhythm in 3 minute's cooling. The local atrial cooling maneuver might be effective for termination of atrial fibrillation.

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