This study aimed to investigate the effects of hyperoxic gas breathing on the disappearance of blood lactate after exercise in two groups having different physical fitness and to determine the most effective O2 concentration in consideration of workload. Our previous study has demonstrated that hyperoxic gas breathing brought out different effects among subjects. In respect of these effects, it was thought necessary to pay attention to exercise intensity. Therefore, the exercise intensity of this study was set by using relative workload of anaerobic threshold (AT) from the aspect of blood lactate. Ten healthy male students participated as subjects and were divided into 2 groups; a group consisting of 5 active students whose mean AT was 60.4% VO2max (Higher AT group) and the other group consisting of 5 inactive students having the mean AT of 48.8% VO2max (Lower AT group). All subjects underwent three cycles of ergometer exercise on a bicycle (workload; 130% AT) for 5 min and recovery session for 6 min. The hyperoxic gas breathing was given only for the recovery session. The conditions of breathing were air, 30, 40, 60 or 80% O2. Blood for determination of the blood lactate level was taken only in the recovery session. When compared with air-breathing, the blood lactate level was significantly reduced in the condition of more than about 60% O2 breathing in Higher AT group, but not in Lower AT one. Together with the previous findings, it was found that the blood lactate level was markedly reduced by more than 60% O2 breathing in Higher AT group without relation to the workload in the range of about 70 to 80% VO2max. In Lower AT group, however, the effects of hyperoxic gas breathing were dependent on the exercise intensity; 30% and 40% O2 breathings were effective for the subjects with more than about 65% VO2max, but not in a lower intensity than it. These results indicate that the effects of hyperoxic gas breathing on the disappearance of blood lactate are dependent on the exercise intensity and the physical capacity.
The purpose of this study was to determine whether the hypothesis on the levels of psychological processes (Hatta, 1977, 1978) accounts for lateral differences in arm positioning movement (a spatial localization task). Fifteen right-handed male subjects were asked to perform a constrained criterion movement, 12 cm in length, with the left or right arm. Then, after a 10-sec retention interval, they were asked to perform the movement with the same arm, estimating lengths of 6, 12 or 24 cm. Different levels of psychological processes were assumed to be involved in estimating these various movement lengths-half, the same, or double that of the original. All possible combinations of the arm (left/right) and three movement length were tested. The CE scores were lower (more accurate) for the left arm (half; 1.5 ± 8.1 mm, same; 4.3 ± 6.2 mm, double; 5.9 ± 20.3 mm) than those for the right arm (half; 5.9 ± 7.6 mm, same; 10.6 ± 10.6 mm, double; 11.8 ± 23.6 mm) in all conditions, indicating a lateral difference (the right hemisphere dominance) in arm positioning tasks. This typical lateral difference, which displayed no significant difference among conditions, is supposed to be mediated by complex or high-level psychological processes. These psychological processes are required by the subjects in the estimation of the various movement lengths. This study suggests that the level of psychological processes is a crucial factor in the manifestation of lateral differences in the performance of arm positioning movements
By means of duplicate meals, we collected food samples of general female residents, aged 50 to 74 years at two suburban districts in Chiang Mai Province, which are distinguished by very high and low incidence rates of lung cancer. Then, on the basis of analyses of their consumption of foods by food groups, we compared their dietary habits in the dry season of northern Thailand with special reference to the difference in lung cancer incidence. In brief, the following features and difference in their dietary habits were found; 1) Rice, vegetables, and pork were most frequently eaten in both the districts. 2) Consumption of fruits, in both quantity and variety, at a high-risk district was much less than that at a low-risk district. 3) Female residents at a low-risk district consumed more variety of green and yellow vegetables than those at a high-risk district. 4) Potato was not found in food samples of a high-risk district. 5) Confectionery was more prevalent in a low-risk district than at a high-risk district.
The experiment is aimed at knowing the effect of “body heating” on color preference. Eleven subjects with normal color vision served as subjects. Two tests, one of the “No Bath” and the other of the “Bath” were conducted. Hot bath immersion with 38.5°C was performed for 30 min from 07:30 h to 08:00 h. Then, they were instructed to choose a single colored cloth out of 41 cloth colors (24 × 52 cm), preferred by themselves, every five min from 08:00 h to 09:00 h under the ambient temperature (Ta) of 27°C. Most subjects preferred cooler color after “body heating” than after “no body heating”. This finding was discussed in terms of greater differences between core temperature and its set point after “body heating”, because cooler color would be helpful psychologically in allowing raised core temperature approach its set point.
Due to comprehensive research on floor heating in Japan and abroad over the last twenty years it is possible today to predict these combinations of comfortable conditions. The specific aim of this investigation is to obtain experimental data upon which the comfortable range of the floor surface temperature could be based, thereby providing a practical and more satisfactory design guide. Accordingly, literatures on floor heating are collected and investigated with the purpose of revealing what the comfort range of floor surface temperature ought to be. Authors tried to obtain a comfortable and permissible floor surface temperature and then reconfirm the maximum comfortable range so that they can propose a reasonable comfortable floor surface temperature and make it fit for practical and extensive use. After synthesizing all the comfortable and permissible values reported in many other papers, this paper finally advances a suggestion on the optimal and permissible floor surface temperatures. Results concerning this subject are as follows. The lowest floor surface temperature would be limited to 25°C, and the highest value to be 31°C. The most optimal temperature for floor surface may as well be within 26-30°C, and it is 21-23°C for the air temperature so that more than 80% subjects can be expected to be comfortable within this recommended temperature interval.
Some apparatuses stimulating the region of tongue innervated by chorda tympani nerve were well known and they were used popularly, but the apparatuses for glossopharyngeal nerve were not produced yet. In the study, the apparatus for the stimulations of glossopharyngeal nerve was trially produced. It was known that the substance of “Umami” was responded well in the tongue region innervated by glossopharyngeal nerve. The evoked potential for the stimulations of monosodium glutamate (MSG) solution which was known as substance of Umami was measured with the use of the trial stimulating apparatus. The evoked potential was detected by monopolar lead for the positions between Cz and A1 (left lobe) with the ground at Fpz. The evoked potential of MSG consisted of a positive peak wave with the latency at approximately 250 ms. The amplitudes increased and the latency decreased as the concentration of MSG increased. The evoked potential stimulating the tongue innervated by this glossopharyngeal nerve could be detected for the first time by the use of the trial apparatus.
Seven male students were exposed to four varied air temperature environments: hot (37°C) to neutral (27°C) (HN), neutral to hot (NH), cool (17°C) to neutral (CN), and neutral to cool (NC). The air temperature was maintained at the first condition for 20 min, then was changed to the second condition after 15 min and was held there for 20 min. Each subject wore a T-shirt, briefs, trunks, and socks. Each sat on a chair and was continuously evaluated for thermal sensation, thermal comfort, and air velocity sensation. Some physiological and thermal parameters were also measured every 5 s during the experiment. The correlation between thermal sensation and skin temperature at 15 sites was found to be poor. The subjects felt much warmer during the rising phase of the air temperature (CN, NH) than during the descending phase (HN, NC) at a given mean skin temperature. However, thermal sensation at the same heat flux or at the same value of the difference between skin and air temperature (Δ(Tsk-Ta)) was not so different among the four experimental conditions, and the correlation between thermal sensation and heat flux or Δ (Tsk-Ta) was fairly good. The multiple regression equation of the thermal sensation (TS) on 15 sites of skin temperature (Tsk; °C) was calculated and the coefficient of determination (R*2) was found to be 0.656. Higher coefficients of determination were found in the equations of thermal sensation for the heat flux (H; kcal·m-2·h-1) at the right and left thighs of the subjects and on Δ(Tsk-Ta) (°C) at 4 sites. They were as follows: TS=2.04-0.016 Hright-0.036 Hleft; R*2=0.717, TS=1.649+0.013 Delta;(Tsk-Ta)UpperArm-0.036 Δ(Tsk-Ta)Chest-0.223 Δ(Tsk-Ta)Thigh-0.083Δ(Tsk-Ta)LowerLeg;R*2=0.752, respectively.