This study aims to identify Single Nucleotide Polymorphisms (SNP) alleles at multiple loci associated with racial differences in skin color using SNP genotyping. A total of 122 Caucasians living in Toledo, Ohio and 100 Japanese were genotyped for the 20 SNPs in the 7 candidate genes. Data obtained from the SNP genotyping were used to analyze associations of the 20 SNP alleles by use of linkage disequilibrium (LD). Combinations of SNP alleles under LD were jointly tested for association with the racial groups by performing a χ^2 test for independence. Results show that the SNP alleles at the multiple loci considered as the haplotype contribute to the differences while suggesting a high probability of LD. Confirmation of these findings requires further study with other ethnic groups to analyze the associations between SNP alleles at multiple loci and racial skin color variation.

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The effects of L-theanine on daytime drowsiness were investigated using the Psychomotor Vigilance Task (PVT) as an objective evaluation and the Visual Analog Scale (VAS) as a subjective evaluation. PVT evaluates the vigilance stage and ability to perform. It measures the reaction time and considers if answers are correct. It was estimated that a decrease in the ratio of correct answers, the prolongation of reaction time, and an increase in the variance of the reaction time tended to lower the vigilance. Healthy male daytime workers were recruited for this study. Data was collected from 13 participants (36.4±4.5 years old) in the morning session and collected from 14 participants (30.8±7.1 years old) in the afternoon session. The study was randomized, double-blind, placebo controlled, cross over design. The evaluations to test drowsiness were performed from 10 AM to 11 AM and from 2 PM to 5 PM. The behavioral controls before the test were referenced with the Multiple Sleep Latency Test. As the active condition, 200 mg of L-theanine were ingested 1 hour before the test. According to PVT result, the ratio of correct answers, the reaction time, and the variance of the reaction were not affected by L-theanine. Furthermore, the VAS showed that L-theanine did not induce drowsiness, but instead, that it maintained appropriate vigilance in the test participants.

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This study aimed to clarify the body heat balance between the human body and its sleep environment. However, because heat transfer coefficients of sleeping positions have not been sufficiently studied, body heat balance of its positions cannot be accurately assessed. Therefore, the purpose of this paper is to propose the radiative heat transfer coefficient of the whole body and the empirical formula of convective heat transfer coefficient of the whole body in natural convection, with focus on the convective heat transfer area of the human body. Measurements were carried out with a thermal mannequin. Experimental posture was supine (floor contact) position. Thermal sensors directly measuring the heat flux and thermal radiation were employed. Experiments were conducted under the following conditions in an artificial climate chamber. Air temperature was set to six cases (ta=16, 18, 20, 22, 24, 26℃). Wall, floor and ceiling temperatures were set to equal air temperature (mrt=ta). Relative humidity and air velocity were kept constant level of 50% and less than 0.2m/s. The following results were obtained. The radiative heat transfer coefficient with supine (floor contact) posture was 3.235W/(m^2・K). The empirical formula of the convective heat transfer coefficient of the whole body with supine (floor contact) posture was represented hc=0.881ΔT^<0.368>[W/(m^2・K)] where the power of the difference between the mean skin temperature corrected by convective heat transfer area and air temperature (ΔT[K]).

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The purpose of this study was to investigate the effects of 12weeks of physical training on cardiovascular responses to postural change at 27℃ and 35℃. 16 sedentary subjects were assigned to either a training group (n=8:30-min ergometer at 60% V^^・O_2peak, 3 days a week) or a control group (n=8 : no exercise). Measurements were made of heart rate (HR), stroke volume (SV), cardiac index (CI), mean blood pressure (MBP), total peripheral resistance (TPR), rectal temperature (Tr), mean skin temperature (Tsk) and heart rate variability (HRV), before and after a chronic physical training. After training, training group significantly increased their V^^・O_2 peak (+10.3%, p<0.01). As for the cardiovascular responses to head-up tilt, in both group there were significant interaction effects between postural condition and ambient temperature in HR, CI and TPR. In training group, HR was significantly decreased after training during head-up tilt at 27℃. These results suggest that the physical training may effect on cardiovascular responses to postural change.

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In 2005, Japan's aged population (aged 65 and above) reached a historic high of 20,560,000, or 20.04% of the total population, exceeding 20% for the first time. Therefore, the problem of an aging workforce and the influence on society in general cannot be ignored. In particular, the detrimental effect of aging on visual information has led to a rapid rise in the number of traffic accidents involving elderly drivers. Because of this situation, the aim of this study is to clarify the cause of decreased visual function with aging, by considering the difference in visual information processing between younger and elderly persons. Two experiments were conducted in this study. The peripheral visual field was measured to evaluate the region in which objects could be detected. Since the distance from fixation point to the visual object is the intensity of stimulus, the psychometric curve is utilized for the peripheral visual field by statistical estimation using the staircase method. Also in the second experiment, the fixation point and saccadic movement as evaluation indices were measured to examine the visual information processing. The results shows following: (1) It is shown that there is no different in the size of the peripheral visual field between younger and elderly person. (2) The latency of saccadic movement extends as people get older. Also, the accuracy of saccadic movement decreases as people get older. (3) Elderly persons took longer than younger persons to recognize the characteristic of the target.

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The purpose of this study is to evaluate the sedative effect of fragrances which have existed in Japan since long time ago such as sakura, ume and fuji. 17 healthy female Japanese subjects were enrolled (21.5±1.3yr). The salivary amylase activity (sAMY) was analyzed during the inhalation of fragrance. Using questionnaire, subjective evaluation was conducted. aAMY was significantly lower during inhalation of fragrance than control. Inhalation of fragrance affected subjects' work performance. Our results indicated that the Japanese fragrances induced the effect in Japanese females, as assessed by both analysis of sAMY and work performance.

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There is no report which examines the change rate of the growth curve in physical growth of infant. The present study is to analyze the growth distance and velocity curves the change rate of height, weight, chest girth, head circumference and BMI in infant. The wavelet interpolation method is applied from 0 to 6 years of these physical items in infant, the growth distance and velocity curves are described, and the derived growth velocity curves are analyzed. A rapid increase for one year after the human was born was especially most remarkable for one month after the birth. When seeing age at largest peak velocity, boys and girls were just 0.05 years (18.3 days) about those all items. When seeing age at first local peak velocity, in height, boys were 1.55 years and girls were 1.50 years, and in weight, both of boys and girls were 1.65 years, and both ages was clearly different. However, that of boys were 1.50 years in both of the chest girth and head circumference, the chest girth was 1.45 years and head circumference was 1.35 years in girls, it was shown that first local peak velocity in the girl was a little earlier than that of boys. The gender difference was already inferred in growth velocity during infant in their head circumference. BMI was showing steady numerical value from 1.50years during infant, and was valid as the index. In conclusion, these data suggest that the aspect of growth velocity curve was made for maturity rate in gender difference clarified during infant.

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