Yumiko Nagai

In a pilot study, we observed the state of "heat shock" in elderly persons living in Osaka and Akita by means of simulating bathing and excretion in winter. Furthermore, using data on indoor thermal environments collected nationwide, we investigated relationships between heating equipment and air temperature in bathrooms and toilets, temperature differences from living rooms, and thermal sensations for the elderly. The pilot study showed that differences in air temperature between living rooms and other rooms were larger in cold latitudes, where there was a subject with remarkably increased blood pressure when moving from the living room to the bathroom or the toilet. According to data from our nationwide survey, temperature differences between living rooms and bathrooms or toilets were the highest around eight o'clock in the evening. Despite similar thermal sensations, actual air temperatures in bathrooms and toilets were lower than those in living rooms. Elderly persons seemed to be tolerant to cold in bathrooms and toilets, although they might be stressed physically. Differences in temperature between living and bathrooms have a tendency to correlate with death rates from bathing.

A survey on thermal conditions of houses was carried out on 331 houses in 11 regions (Sapporo, Akita, Sendai, Chiba(north), Chiba(south), Shizuoka, Toyama, Osaka, Hiroshima, Fukuoka and Kagoshima) from December, 2004 to March, 2005. The air temperatures in the living room, bathroom, dressing room, toilet, corridor, bedroom and outdoor of houses were measured evety minute for 7 days. The water temperatures of bath during bathing were also recorded. The thermo-recorders which measured air temperatures at a height of 0.6-1.1m were kept out of the sun. The following results were obtained. (1) The room temperatures in Sapporo were kept above 15℃ in all rooms in winter. On the other hand, only living rooms were kept warm in the rest of regions. (2)The room temperatures in dressing rooms and/or corridors were vety low in all regions, except in Sapporo, (3)The mortality rate ofdrowninginthe 11 regions was correlated withthe room temperature in the dressing room.

The purpose of this research was to examine effect of the sports shoes which change shape by use on lumbar part and lower limbs. Subjects were 251 people who belong to a college student track-and-field part. 1) Relation was accepted between the usable years of shoes, and injury of a waist and the leg. The injury of the thigh was occurring frequently to the person who used shoes seven months or more. The injury of the lower legs and foot were occurring frequently to the person who used shoes less than six months. 2) Those to whom the tiptoe inner side of an out sole was worn out have the high danger that injury would occur in the thigh and lower limbs. Those to whom the out sole heel outside was worn out have the high danger that injury would occur in lower limbs. Additionally, those to whom both the out sole heel outside and the tiptoe inner side of an out sole were worn out have the high danger that injury would occur in lower limbs. 3) Relation was not accepted between wear of the heel partial outside of an out sole, and supination injury. Furthermore, relation was not accepted between wear of a shoes inner side, and pronation injury. 4) Use of shoes seven months or more wears the heel outside of an in sole, and the root portion of the little toe of an out sole. However, relation was not accepted between other wear parts and usable years of shoes.

The purpose of this study was to compare bathing conditions in each area of Japan and to find the features of them in order to investigate factors affecting regional differences in death rates in the bathroom. In this study, a questionnaire survey was carried out in 11 areas, Sapporo, Akita, Sendai, northern and southern Chiba, Shizuoka, Toyama, Osaka, Hiroshima, Fukuoka, and Kagoshima. Questionnaires were distributed to approximately 30 detached houses in each area twice in summer and winter. Subjects were asked on passed years after building their houses, fixtures and thermal sensations in the houses, behaviors during bathing, and so on. Answers showed the regional differences in bathing conditions among areas as follows: From the view points of retentiveness and insulation of heat, newer and northern houses are better than older and southern ones. Unexpectedly, subjects of the southern areas reported colder thermal sensation in the bathroom in winter than those of the northern areas. There were regional differences in frequency and duration of bathing, and the person who take a bath first It seems that there may be the relationship between the bathing condition in each area and death rates in the bathroom, but ftirther investigations are needed.

Five healthy young and elderly female volunteers slept from 23:00 to 7:00 in a climate chamber that was controlled at 13℃ 60% RH. The lower extremity area of the futon was heated by using an electric blanket before sleep. Bed climate, body movement, skin temperature (T_<sk>), and heart rate were measured continuously throughout the night. Subjective sensational and sleep evaluations were conducted before and after the recording sessions. The bed climate of the foot area was significantly lower in the elderly. During wake, the finger and toe T_<sk> was significantly higher in the elderly, while that of the chest was lower. During sleep, the chest and mean T_<sk> were significantly higher in the young. The sleep maintenance factor of the subjective sleep evaluation was significantly better in the elderly. These results suggest that chest and mean T_<sk>, bed climate of the foot area and subjective sleep evaluation when an electric blanket is used before sleep may differ depending on age. The usage and the temperature level setting of the electric blanket should be adjusted according to age.

In the maker's office space with a multi-board radiant cooling system, subjective response, e.g. thermal comfort, thermal sensation etc., and skin temperature of occupants were measured as well as thermal conditions, e.g. air temperature, air humidity, etc. We focused on the air temperature to evaluate the thermal condition, because air temperature is decreased by the multi-board type of radiant cooling system more than by the single-board type. It was shown that a radiant cooling system is suitable to use in an office and that mechanical ventilation is recommended to use together with a radiant cooling system.

In order to investigate the physical, economical, physiological and psychological aspects regarding ancient lighting, two series of experiment were performed. At first a darkroom (1.3×4.5 m, Ht: 2.7m) was constructed. In experiment I, illuminance and consumption rate of fuel were measured. The Japanese classic candle, plant oil and animal fat yield I.12, 0.30-0.62 and 0.05 Iux at 1.0 m distance, respectively. The illuminance was reduced to about 50% by andon which was a lighting tool of folkcraft. The burning duration of plant oil was about two weeks to 180 ml when it burned 4 hours per one day. In experiment II, 15 young females were examined regarding the visual properties such as visual acuity, readability of newspaper and discrimination of color under the simulated illumination of candle. The visual acuity was 0.42 under 0.16 Iux. It needed more than 1.44 Iux to read a newspaper.In the color discrimination test, yellowish green was most difficult, silver or long wave range colors were easy.

Subcutaneous fat is an essential element in shaping the body of human beings. In this research, skinfold thickness was measured specifically in 33 regions of the human body, including the abdomen and buttocks. Based on our measurements, the subcutaneous fat distribution was assessed for several age groups. The subjects were healthy Japanese women aged 20 to 58 years. Skinfold thickness was measured using the B-mode ultrasound methods, together with anthropometric measurement. A comparison was made between the following five age groups: early 20's, Iate 20's, 30's, 40's and 50's. The measured values for the early 20's group were used as the standard and the relationship between increase ratio of subcutaneous fat and age was studied. Through our research, we obtained data on the subcutaneous fat distribution in each age group. The largest change was observed between the ages of the early 20's and late 20's. The skinfold thickness measurements of the abdomen and buttocks was consistently around 10 mm for the early 20's, and increased up to 23.8 mm on the rear side section for the late 20's. This result indicates that the increase ratio varied depending on the part of body. Furthermore, the changes in skinfold thickness were different in specific parts of the abdomen and buttocks among different age groups. The difference in skinfold thickness between upper and lower sections of the abdomen also becomes more pronounced with age. Skinfold thickness increased significantly between the early 20's and late 20's. Among the body regions, measurements at the rear side showed the largest change with age; averaging 11.3 mm for the early 20's compared to 33.6 mm for the 50's. The subcutaneous fat distribution on the buttock also showed the differences wlth age, indicating changes in body shape. Using careful measurements of the abdomen and buttocks, subcutaneous fat distribution among each age group was determined as well as the variation in changes with the aging process.

In order to investigate the physical, economical, physiological and psychological aspects regarding ancient lighting, two series of experiment were performed. At first a darkroom (1.3×4.5 m, Ht: 2.7m) was constructed. In experiment I, illuminance and consumption rate of fuel were measured. The Japanese classic candle, plant oil and animal fat yield I.12, 0.30-0.62 and 0.05 Iux at 1.0 m distance, respectively. The illuminance was reduced to about 50% by andon which was a lighting tool of folkcraft. The burning duration of plant oil was about two weeks to 180 ml when it burned 4 hours per one day. In experiment II, 15 young females were examined regarding the visual properties such as visual acuity, readability of newspaper and discrimination of color under the simulated illumination of candle. The visual acuity was 0.42 under 0.16 Iux. It needed more than 1.44 Iux to read a newspaper.In the color discrimination test, yellowish green was most difficult, silver or long wave range colors were easy.

Subcutaneous fat is an essential element in shaping the body of human beings. In this research, skinfold thickness was measured specifically in 33 regions of the human body, including the abdomen and buttocks. Based on our measurements, the subcutaneous fat distribution was assessed for several age groups. The subjects were healthy Japanese women aged 20 to 58 years. Skinfold thickness was measured using the B-mode ultrasound methods, together with anthropometric measurement. A comparison was made between the following five age groups: early 20's, Iate 20's, 30's, 40's and 50's. The measured values for the early 20's group were used as the standard and the relationship between increase ratio of subcutaneous fat and age was studied. Through our research, we obtained data on the subcutaneous fat distribution in each age group. The largest change was observed between the ages of the early 20's and late 20's. The skinfold thickness measurements of the abdomen and buttocks was consistently around 10 mm for the early 20's, and increased up to 23.8 mm on the rear side section for the late 20's. This result indicates that the increase ratio varied depending on the part of body. Furthermore, the changes in skinfold thickness were different in specific parts of the abdomen and buttocks among different age groups. The difference in skinfold thickness between upper and lower sections of the abdomen also becomes more pronounced with age. Skinfold thickness increased significantly between the early 20's and late 20's. Among the body regions, measurements at the rear side showed the largest change with age; averaging 11.3 mm for the early 20's compared to 33.6 mm for the 50's. The subcutaneous fat distribution on the buttock also showed the differences wlth age, indicating changes in body shape. Using careful measurements of the abdomen and buttocks, subcutaneous fat distribution among each age group was determined as well as the variation in changes with the aging process.

The purpose of this study is to obtain some knowledge related to physiological and psychological effects of head heating by radiation on the vital body under varying conditions of the environmental temperature and physical activity. The study was proceeded with experiments 1 and 2 using 8 women, all in good health as subjects. In experiment 1, firstly the subject at rest was kept at an ambient temperature of 28℃ for 40 minutes. Then, moving to a room kept at an ambient temperature of 18℃ or 28℃ , the state at rest was maintained with head heating at 3 radiant intensities (without radiation, 35℃ and 40℃ of globe temperature) for a further 40 minutes. In experiment 2, continued from the same procedure of experiment 1, work on the ergometer was performed for 30 minutes with head heating at 2 radiant intensities (without radiation and 35℃ of globe temperature). Items measured were tympanic temperature, skin temperatures, heart rate, and subjective sensations. The principal results obtained are as follows: 1) Tympanic temperature, forehead skin temperature and score of thermal sensation of head increased, while the others decreased at 18℃ . 2) Decrease of scores was inhibited by head heating in finger skin temperature, toe skin temperature and heart rate. 3) When radiant intensities at 35℃ and 40'C were compared, statistical significant difference was noted in forehead skin temperature only, the difference of radiant conditions gives a little effect to the vital body. 4) Effects brought by head heating during rest decreased owing to the addition of work.

The purpose of this study is to obtain some knowledge related to physiological and psychological effects of head heating by radiation on the vital body under varying conditions of the environmental temperature and physical activity. The study was proceeded with experiments 1 and 2 using 8 women, all in good health as subjects. In experiment 1, firstly the subject at rest was kept at an ambient temperature of 28℃ for 40 minutes. Then, moving to a room kept at an ambient temperature of 18℃ or 28℃ , the state at rest was maintained with head heating at 3 radiant intensities (without radiation, 35℃ and 40℃ of globe temperature) for a further 40 minutes. In experiment 2, continued from the same procedure of experiment 1, work on the ergometer was performed for 30 minutes with head heating at 2 radiant intensities (without radiation and 35℃ of globe temperature). Items measured were tympanic temperature, skin temperatures, heart rate, and subjective sensations. The principal results obtained are as follows: 1) Tympanic temperature, forehead skin temperature and score of thermal sensation of head increased, while the others decreased at 18℃ . 2) Decrease of scores was inhibited by head heating in finger skin temperature, toe skin temperature and heart rate. 3) When radiant intensities at 35℃ and 40'C were compared, statistical significant difference was noted in forehead skin temperature only, the difference of radiant conditions gives a little effect to the vital body. 4) Effects brought by head heating during rest decreased owing to the addition of work.

Since the health hazard of asbestos fibers has been widely recognized, the number of asbestos abatement projects in schools has increased rapidly. Most of these projects were planned during summer vacation from school. However, in Japan, it is hot and humid in summer. Moreover, the workers have to wear impermeable protective clothing because of the asbestos exposure risk. The purpose of this survey is to study the workload of asbestos abatement work by measuring physiological reactions. Physiological strains of 12 male workers and working conditions during asbestos abatements work in two schools were measured in August in 1988 and in 1989. Body weight loss by the work of all workers was measured, and heart rate, rectal temperature and skin temperatures at five sites of some of them were measured every minute.