Tremor is an invisible mechanical vibration observed on parts of the body. It is classified into physiological and pathological tremors. It was reported that an oral dose of alcohol could decrease the amplitude of pathological tremor. Usually, drunken level is estimated by the alcohol concentration in expiration. But, physiological tremor can be used to estimate drunken level easily. In this paper, power spectrum of the physlological tremor of index finger and some reaction time of the pedal operations of imitated car driving were measured every 15 minutes for 3 hours under drinking and non-drinking conditions. Subjects were 10 males aged 20 to 25 years. Under drinking condition, the total power values of tremor from 15 to 180 minutes after drinking were smaller than that of before drinking. It is clear that the influence of drinking could be estimated by the total power of the physiological tremor, even when the significant difference of the influence of drinking on reaction time was not found.

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The present study was made to search for the origin on human dorsal surface, whlch is available for a correct grasp of a change of body surface (skin surface) with human activities and to try to re-evaluate, using the above origin, quantitative skin daformation of human dorsal surface on raising arms. The following results were obtained : l) X. examination in standing (static) and arm-raising (dynamic) positions revealed a site with inter-positional difference, as zero, in slippage on dorsal median line. This site was supposed to be the origin and was confirmed to be Th₁0 and Th₁2. The palpation of the site of, Th₁0 and Th₁2 on dorsal medlan line was thought to be simple and effective in searching for a site with the least bone and skin slippage, thus in presuming the origin. 2) Based upon the origins on dorsal median line and scapular line parallel thereto in sitting position, 5 cm φ-correct circles were stamped up and down, then arm raising action was taken. The utilization of the origin enabled us to determine the length, l, directional angle, θ, and area, S, of the slippage between correct and distorted circles as obtained by these actions. 3) For arm raising, the skin slipped up and down on median line for lower and higher sites than the origin, respectively, with the angle θ on scapular line indicating the + direction, while l and θ appeared greater and smaller for a nearer site to the origin, respectively. 4) S showed a tendency to have greater and smaller changes at lower and higher sites on median line than the origin, respectively, while on scapular line, the areal change generally appeared greater than that on median line, having a tendency to be greatest at a near site to the origin, with a decrease according to a lower site than the origin Besides S and S' as obtained in an origin-free condition proved to be SS'. Therefore, the involvement of the origin in the grasp of the skin change on human dorsal surface was confirmed.

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Experiments were conducted to examine the visibility of different floor levels from a stumbling point of view. The test subjects were the elderly and the young, and we compared the difference between the two. We investigated eye movement while they were scanning the different floor levels. The results were as follows : 1) The height of different floor levels and illuminance had an influence on the visibility of different floor levels. Especially, the elderly were easily influenced by them. 2) The eye movements in scanning the different floor levels did not relate to the visibility of them, but were related to the personality of the test subjects. Eye movement patterns of the elderly differed from that of the young. The elderly were scanning mainly the lower part. The eye fixation time of the elderly was longer than that of the young. From the results, it was clarified that there were the difference betlveen the elderly and the young. We could show it by the degree of influence. For example, the influence by the change of environmental condition.

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To investigate the effects of wearing compression stockings on cardiovascular responses, the heart rate (HR), cardiac output (Q) measured by CO₂ rebreathing method, and oxygen intake were measured at rest in a supine position for 40 min and standing position for 120 min. Six female subjects wore the compression stockings after 20 min of rest at supine position. The oxygen intake and ventilation showed no significant difference between with and without the stockings. Q at standing position was lower than that at supine position by an act of hydrostatic pressure. However this decrease was lower with stockings than that without stockings. The compression stockings used in this study might improve the venous return to the heart. However, the subjects complained of discomfort due to the high clothing pressure. In the second experiment, the authors estimated the minimum pressure required in improving the venous return. The subjects wore the trousers having two bladders inflated by air pressure. The trousers could compress the leg (contain the foot) and thigh individually. From the relationship between air pressure and Q, the estimated minimum pressures were 17 mmHg for the leg and 15 mmHg for the thigh.

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The purpose of this study was to evaluate the effects of two types of underwear materials on thermophysiological responses during rest and light exercise. Two differently moistureregaining underwear materials were tested : 100% cotton (COTTON) and 100% acrylic (ORLON). Nine female subjects participated in the experiments at an ambient temperature of -10°C. The experiment comprised a 20-min of rest, a 40-min of walking exercise (6 km/ h) and a 40-min of recovery. No significant differences could be found in the average values of core temperature, skin and clothing temperatures, amount of non-evaporated and evaporated sweat or subjective ratings of thermal sensations within the two different underwear ensembles. The amount of sweat accumulated into the underwear was very low (3 ± 1g) and (5±3g) (mean±SE) in COTTON and ORLON, respectively. In both ensembles moisture was tranferred towards outer layers of the clothing where the amount of moisture correlated significantly with the total sweat production. In a heavily sweating individual, however, the properties of COTTON underwear, such as wicking ability and high moisture regain, became apparent (accumulated sweat 71g) compared to ORLON (46g). It is concluded that the underwear materials have no significant influence on the thermophysiological responses or subjective sensations under the conditions studied, especially when the sweat rate is low. On the other hand, in individuals with a higher sweating rate the differences between materials may become evident even during light exercise.

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Recently spaces for the aged have become more wide spread as the population of them has increased. Most of the spaces, however, are originally provided for the young and, accordingly, can not be considered preferable environments for the aged. From this point of view, the authors aimed at the visual environments for the aged and carried out experimental research on the influences that. aging gives to recognizability for colored targets, for the purpose of providing a preferable visual environment for the aged. The results show that the recognizability for colored targets declines drastically from about fifty years old, as just as the recognizability for uncolored targets. Moreover, the results show that, although the recognizability of the young is considerably influenced by differences of the illuminance and color of the target surfaces, aging made the recognizability less influenceable by these differences.

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