It is a well-known fact that the skin surface pH has weak acid. Recent many studies have shown that skin barrier role and atopic dermatitis (AD) related to the skin surface pH. The final goal of this study is to develop a multifunctional skin measurement system for portable use, to evaluate data as pH, water content and etc. However, those methods have some limits, such as when measuring skin surface pH which by using the glass electrode, there is the need to add water on the skin, influencing the water content measurement. We developed the measurement system with Dry-pH-sensor that consists of a platinum wire electrode and Ag/AgCl wire electrode, based on the Nernstian response. The purpose of this study was to examine whether the pH sensor could measure the skin surface pH without any water added, same as using water added glass electrode. Skin surface pH was measured for 2 minutes with using the sensor and glass electrode measurement was performed. The correlation between the sensor response averages of 90-120 s and skin surface pH was found (R=0.98). We concluded that Dry-pH-sensor could measure skin surface pH with same response as traditional sensor, without using any water.

Developing robotic systems that can encourage the social activities of the aged or handicapped is important. We propose a mobile robotic system that follows a person, closely monitoring when the person goes out of the house; becomes a chair when the person wants to sit; and assists in the standing-up motion when the person resumes walking. The mobile robot comprises an arc-shaped mechanism to assist in the standing-up motion. In this study, the standing-up motion of a person is analyzed from the viewpoint of the combination of the lateral movement of the knee and the rotational movement of trochanter major when its rotational center is considered to be in the same position as the knee. In addition, the rotational movement of trochanter major and the lateral movement of the knee are modeled using spline functions. The errors between the trajectories obtained by the models and those obtained from experimental data were confirmed to be very small, showing the effectiveness of the models. The mobile robot can reproduce the trajectory of natural standing up by controlling its own movement and the arc-shaped mechanism by following the trajectories of the models.

We developed a dorsiflexion support RT (Robot Technology) for patients with paralytic equinus. It is composed of a rubber artificial muscle, which assists the dorsiflexion muscle while walking. We conducted clinical trials on the dorsiflexion support RT in five patients with paralytic equinus. We conducted a 10-m walk test using a pre-post design for validating the adaptability of and the immediate effect of the dorsiflexion support RT on the muscle. We set the following two indices for evaluating dorsiflexion: differences in the ankle joint angle during dorsiflexion between toe off (pre-swing phase) and mid-swing phases and the toe clearance, which is the angle between the floor and sole during the initial contact phase. Results revealed that the ankle joint angle during dorsiflexion increased by 7.5° and the toe clearance increased by 4.2° after the intervention. Therefore, it is possible to effectively improve the abnormal gait of patients with stroke using this device. Also, It is considerable to obtain an immediate effect for learning gait in short-term. In the future, the number of clinical cases demonstrating the medium- and long-term intervention effect needs to be increased.

In this paper, we developed a magnetic field generating coil for finding out an effective magnetic field for supercooled freezing of biological tissues under the magnetic field. The range of the frequency and the magnetic flux density of the inducing magnetic field was expanded by reducing the resistance compared with the previous coil. The upper range of the frequency increased from 2 kHz to 10 kHz and that of the magnetic flux density increased from 0.3 mT to 2.0 mT. We evaluated the magnetic field dependency of the degree of supercooling of the porcine ovarian tissues using the developed coil. In supercooled freezing, it is reported that the growth of the ice crystals, which is a cause of cell destruction, was suppressed with the increase of the degree of supercooling. This result indicates that increasing the degree of supercooling may enable to prevent cell destruction. Therefore we evaluated the effect of the magnetic field by measuring the degree of supercooling. As a result of the measurement, the averages of the degree of supercooling at 10 kHz frequency of 2.0 mT magnetic field increased the most from 9.1 ± 1.7 °C for without magnetic field to 10.5 ± 1.7 °C.