In a series of experimental shift-work studies, individual differences in adapting to a new schedule were examined after a time shift of 12 hours. Four male students (A.D)participated on a normal schedule (sleeping period:00:30-07:30) for two days and on a shif tschedule (sleeping period:12:30-19:30) for two days.Mah-jong game was loaded in most awaking times.Oral temperature was measured and urine was collected every 4 hours except during sleep.At the same time, the subjects completed a fatigue feeling scale and a sleepiness scale.No obvious individual differences on the circadian variations of oral temperature, and urinaryadrenaline and 17-OHCS were observed on the normal schedule.However, the variations in these physiological indices on the shift schedule were classified into two types.Whereas the circadian period of oral temperature rhythms in subjects A and B which was equal to 24-hours was maintained, these rhythms in subjects C and D shifted and had two peaks in a day. The variations in adrenaline and 17-OHCS excretion in A, B-group were also different from thosein C, D-group.The acrophases of the excretion rhythms in A, B-group were preceded by those in C, D-group.The subjective ratings of fatigue and sleepiness in subjects A and B tended to be higher than those in subjects C and D on the shift schedule.

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A computer simulation in the expiratory flow method was utilized to obtain information on the effects of error factors on the gas exchange during breath-by-breath measurement.The error sensitivites of gas exchange variables (V_O_2, V_CO₂, and R) to the error in expiratory flow integration were always one, while the error sensitivities to the flow base-line drift decreased with the reduction of expiratory period.V_O_2 values were affected by dhfts in both expired oxygen and carbon dioxide concentration.A combined error of the integrals of flow and the integrals of product of flow times gas concentration caused multiple effects on V_O_2, depending on the sign and magnitude of theintegrals.Problems in this simulation were selection of average gas consentration in the integrals, application to the transient response, and lack of the wave form analysis of distorted signals.

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The effects of speed and gradient on stereotyped pattern of temporal-distance parameters of the lower limb in human gait were observed on five male subjects walking on a treadmill.Step length and step duration were consecutively determined by means of a computerized system.Step lengrt hincreased approximately in proportion to the square root of the speed, and step duration decreased in proportion to the reciprocal of the square root of the speed.In grade waiking, when compared with level walking, the subject had a tendency to take shorter steps at high speeds and longer steps at low speeds.Standard deviations of step length and step duration showed the minima at the speeds which were estimated to be about 90 and 95m/min for step length and step duration, respectively, although there were some variations of the speed with gradient.Coefficients of variation of these factors also showed the minima at particular speeds.These results suggest that when the subject is allowed to choose his own step length, there exists the speed at which the fluctuation of stereotyped movement of lower limb shows the minimum.

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The associations of seven variables-age, body mass index, alcohol consumption, cigarette smoking, type of work and stress as related to work-with systolic and diastolic blood pressure were studied in 1447 male workers aged from 20 to 63 years in a factory.The quantification theory mode I was employed to determine which variables were independently associated with blood pressure and how much were the magnitudes of associations of them.Body mass index, alcohol consumption, age, physical exercise, cigarette smoking and stress as related to work were attained as the predictors for systolic blood pressure in decreasing order of the relation of each variable to systolic blood pressure.For diastolic blood pressure, body mass index, age, alcohol consumption, physical exercise and cigarette smoking were attained as predictors.These results were discussed compahng with the effects of each variable on blood pressure in experimental and any other population studies.

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This project was performed to clarify the learning effects on the fmction of visual attention and maintaining of it indicated by the TAF (target-aiming function) test.A standardized curve of the TAF-test was obtained from six healthy male students, being tested for three days, five times a day.In a ddition, observations of the TAF were made when scores were at their highest values.The displacement of the body's center of gravity during all TAF-tests was measured,

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This project was carried out to clarify the mental work load on programmers using VDT.Subjects were nine male programmers aged from 23 to 33 years.They used VDT at a low frequency and worked in a self-paced system.Critical fusion frequency, ocular accommodation, subjective feelings of fatigue published by Japan Association of Industrial Health, cumulative fatigue index, working hours and work elements of VDT were measured.

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An optical multichamel detector system detects whole spectra simultaneously.Therefore it enables spectral measurement of light fluctuating rapidly in intensity or in spectral composition, which is difficult or impossible by other means.An optical multichamel detector system including original computer programs has been constructed and spectra of ultraviolet light from arc weldings have been measured by this system.Complicated spectra containing a great number of spectral lines have been obtained, which could not be measured before the development of optical multichamel detector systems.

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The problem of human adaptation is so funda-mental that many textbooks appeared so far.The author briefly took up this subject previously (Ueda, 1984), so the topics will be reiterated not from the same point of view, but from the other angles.Most physiologists tend to investigate only a short period of phenomena, though anthropologists seem to take a long period of changes into consideration.Thus by means of physiological anthropology, the study of human will be better developed.

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