The objective of the present study was to establish standard values for the salivary and urinary cortisol concentrations, since cortisol levels are often used as stress indicators. Saliva and urine samples were collected from 85 men and 81 women, between the ages of 20-59 years, at five different times (when they got out of bed, 10:00, 11:40, 14:00 and 16:00) on two different days (one workday and one holiday). Cortisol concentrations were determined by the HPLC method, and standard values (mean±S.D.) were calculated in relation to sex, measurement time and day. In addition, the concentration of cortisol in 299 saliva samples and 155 urine samples was determined by the RIA method to derive a simple equation to compare the RIA and HPLC methods. Under transient stress, the level of salivary cortisol deviated greatly from the standard value, suggesting that the present standard values are useful in assessing stress. Finally, the scope of application of standard value tables was discussed.

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The purpose of this study was to compare baseball pitches between skilled and nonskilled pitchers using a three-dimensional cinematographic analysis. Nine baseball pitchers were used as subjects. The pitching motions were filmed by two high-speed cameras. The time series of three-dimensional landmark coordinates of the subject and the ball during the baseball pitch were calculated using the DLT method. First, the index called SFD (Shoulder Fulcrum Dispersion) which expresses quantitatively the dispersion of the shoulder joint on the opposite side of the throwing arm was proposed to compare the SFD between skilled and nonskilled pitchers. Next, kinematic parameters such as abduction/adduction (AA) angle at the shoulder joint of the throwing arm, horizontal flexion/extension (HFE) angle at the shoulder joint of the throwing arm, backword/forward lean (BFL) of the upper torso, and right/left lean (RLL) of the upper torso were calculated to investigate the hypothesis that these parameters of the skilled pitchers were less different between types of pitch (fastball and curveball pitches). As a result, it was indicated that the skilled pitchers had smaller SFD than the nonskilled pitchers. The kinematic variables such as AA, HFE, BFL and RLL of the skilled pitches were found to be not different between types of pitch as compared with those of the nonskilled pitchers.

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Visual imagery plays an important role in design activity. In this paper, we dealt with “eidetic imagery (EI), ” that is, a visual representation of a previously perceived object, and conducted a fundamental research to clarify functions of EI in the design activity. 114 undergraduates in industrial design course answered our questionnaire through which we intended to review usage of visual imagery in daily life. The 15 subjects from the questionnaire survey participated in the EI test. As a result, 4 were found to be eidetic (eidetikers). They had a particular tendency common to all of them: they are more absorbable in imagination and fantasy than non-eidetikers. The result also suggests that eidetikers have an advantage in behaviors such as retention of visual image and imaginal operations, which is an essential part of design activities.

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This study was designed to investigate the factors which affect the impression of road traffic noise and to find the effective countermeasures to improve sound environment. A preliminary experiment was conducted with 30 different kinds of road traffic noise in order to select sound sources to be used in Experiments 1 and 2. It was found in the preliminary experiment that LAeq showed fairly good correlation with noisiness. However, there were some sounds whose noisiness deviated from the regression line. In Experiment 1 the impression of 10 kinds of road traffic noise was judged using semantic differential. The LAeq values of the sounds were kept equal. It was found that sounds which dominantly consisted of engine noise or exhaust noise were judged as being “shrill” and “powerful”. The impression of “powerful” showed high correlation with loudness level based on ISO 532B and fluctuation strength and the impression of “shrill” with calculated sharpness. The impression of “pleasant” was found to be affected by many factors such as sound pressure level, frequency characteristics and temporal fluctuation of the sound. Experiment 2 was conducted in order to confirm the result of Experiment 1 using the method of paired comparisons. It was suggested that the sound quality was affected by loudness level, fluctuation strength and sharpness. The possible countermeasures to improve the impression of road traffic noise were discussed on the basis of the results of the experiments.

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To evaluate upper arm muscles size and strength in contemporary Japanese adults, the cross-sectional area (CSA) and maximum voluntary isometric strength of elbow flexor and extensor muscles were examined on 102 men and 116 women. Each subject was assigned to one of three age groups (3rd, 4th-5th, and 6th-7th decade). The cross-sectional areas of upper arm flexor and extensor muscles were estimated by our previously developed ultrasonographic measurement system. Voluntary strength of the elbow flexors and extensors was measured isometrically. While there were no difference in elbow flexor and extensor CSA with age in men, the elbow flexor and extensor CSA for the 3rd decade of women were significantly smaller compared to those for middle-age and elderly women. Male isometric elbow flexor strength in the 4th-5th decade was significantly larger than those in the 6th-7th decade, whereas no such age-dependent change was evident in extensor strength. For women, both elbow flexor and extensor strengths for the 3rd decade were the smallest among the three age groups. The aging-associated reduction of muscle strength per unit of muscle CSA in the elbow flexors started from the 6th or 7th decade in men. The muscle strength per unit of muscle CSA in the elbow extensors was not significantly different between each age group for both men and women. In conclusion, the fact that contemporary Japanese young women have a relatively small CSA and strength in their elbow flexors and extensors should be recognized for exercise-health programs.

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