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The purpose of this study was to investigate whether, when subjects were living in a moderately warm environment: (1) the softness of clothing worn during the daytime could influence the subjects’ preference in the evening for the softness of clothing and a face towel; and (2) the softness of bedding materials could modulate their nocturnal body temperature, overnight urinary catecholamine excretion, and sleep quality. Six females were tested during the luteal phase of their menstrual cycles. The experiment was conducted over three consecutive days and nights in a climatic chamber controlled at 28 ± 0.2 °C and 50% RH during the evening (from 19:30 to 21:30 h) and at 29 ± 0.2 °C and 50% RH during the sleep period (from 22:30 to 07:00 h). The first night was for adaptation to the experimental chamber. Five different sets of clothing and bedding were used; these were identical except for the softness/hardness of the materials used (due to treatment with fabric softener or starch), and material softness decreased in the order: Type A (softest) > Type B > Type C > Type D > Type E (hardest). There were two phases to the experiment, conducted in random order. In one phase, subjects wore “soft type” (Type B) T-shirt and shorts in the daytime and, in the other phase, “hard type” (Type D/E) T-shirt and shorts. In both phases, subjects were asked at 21:30 h to select a T-shirt and a face towel which they felt would be most comfortable to use. At night, they slept on bedding (a mattress cover, a pillowcase and a covering blanket) which was of the same degree of softness as the T-shirt and shorts that had been worn in the daytime in that phase. Rectal temperature, skin temperatures at seven sites, and body movement were measured during sleep, an overnight urine sample was taken for measurement of urinary excretion of adrenaline and noradrenaline, and subjective sleep quality was assessed on being woken the following morning. The main results were as follows: (1) T-shirt preference in the evening showed large inter-individual variation but did not differ significantly between the two phases (when “hard type” or “soft type” clothing had been worn during the daytime). The preferred texture of the face towel was softer than that of the T-shirt, the difference in softness between the chosen face towel and T-shirt being significant (p < 0.05 andp < 0.10, respectively, when having worn “soft type” and “hard type” clothing in the daytime). (2) Rectal temperature and mean skin temperature were not significantly different when sleeping with “soft type” (Type B) and “hard type” (Type D/E) bedding materials. (3) Overnight secretions of urinary adrenaline and noradrenaline were significantly less with “soft type” than “hard type” (p < 0.01 andp < 0.05 for adrenaline and noradrenaline, respectively) bedding. (4) When sleeping with “soft type” bedding materials, five out of the six subjects showed less body movements during the sleep period and reported that they had slept better. These results suggest that, in a moderately warm environment, bedding materials with a softer texture might be more comfortable to the subject (due to less tactile stimulation of the skin, which results in neurophysiological relaxation) and provide them with better sleep quality. [ABSTRACT FROM PUBLISHER]

In human circadian rhythm research, rectal temperature is the traditional gold standard for estimating core temperature, but the measurement of rectal temperature is inconvenient and unacceptable to some subjects. This study examined whether the circadian rhythm of forehead skin temperature would be an alternative to that of rectal temperature in sedentary subjects living in a thermally neutral environment. Six healthy female volunteers participated as subjects for 37.5 h, from 21:30 h on day 0 to 06:30 h on day 2. They were tested twice while wearing two different types of clothing. One type of clothing covered the whole body except the head and hands (Type L); the other exposed the head and distal extremities (Type H). Subjects lived in a climatic chamber controlled at 23.8 ± 0.2 °C and 60 ± 5% RH with light intensity of 500 lux from 06:30 to 19:30 h, 100 lux from 19:30 to 22:30 h and 0 lux from 22:30 to 06:30 h. Rectal temperature and skin temperatures at seven sites were recorded continuously at 10 min intervals. The extent to which the circadian rhythms of forehead and hand skin temperature mirrored that of rectal temperature was determined by cross-correlation and cosinor analyses. Cross-correlation analysis of data from the group or individuals, and whether wearing Type L or Type H clothing, indicated that the profile of forehead skin temperature was similar to that of rectal temperature, with highly significant positive correlation coefficients (r = 0.9099–0.9744) and time lags of 0.17–0.33 h. By contrast, the profile of hand skin temperature was approximately in antiphase, with smaller correlation coefficients (though still highly significant:r = 0.6036–0.7526), and with time lags of 11.00–14.11 h. Cosinor analysis indicated that the acrophase of the circadian rhythm of forehead skin temperature for individuals was slightly, but not significantly, earlier than that of rectal temperature with both types of clothing (0.54 ± 0.68 and 0.35 ± 0.64 h with Type L and Type H clothing, respectively). The circadian rhythm of forehead skin temperature showed a significantly greater amplitude and lower mesor than rectal temperature, whether wearing Type L or Type H clothing. Individuals’ data gave 0.38 ± 0.09 and −2.92 ± 0.31 °C, respectively, with Type L clothing and 0.40 ± 0.26 and −2.86 ± 0.35 °C with Type H clothing; these differences were not significantly different between the two types of clothing. It is concluded that, in sedentary subjects living in a thermally neutral environment, forehead skin temperature gives information regarding phase and some aspects of amplitude that can act as substitutes for rectal temperature data. [ABSTRACT FROM AUTHOR]

This study investigated skin temperature, the nocturnal secretion of urinary 6-sulfatoxymelatonin (aMT-6s), and self-estimated sleep propensity in subjects living in a thermally neutral environment but wearing two types of clothing which provided different thermal insulation to the extremities. The experiment was conducted from 21:30 h on day 0 to 06:30 h on day 2 in an environmental chamber controlled at 24 ± 0.2 °C and a relative humidity of 50 ± 5%. Seven healthy female volunteers participated twice, while wearing “covering” or “exposing” types of clothing. The “covering” type of experimental clothing consisted of long-sleeved shirts, full-length trousers and socks (Type L, weighing 1042 g); the “exposing” type of clothing consisted of half-sleeved shirts and knee-length trousers (Type H, weighing 747 g). During nocturnal sleep (from 22:30 h to 06:30 h), all subjects were covered by two thin sheets made of 100% cotton. When wearing Type H clothing, the nocturnal fall of forehead skin temperature tended to be greater (p = 0.07) and hand skin temperature was significantly lower during time awake (p < 0.05) with a greater nocturnal increase (p < 0.05). The distal-to-proximal skin temperature gradient, DPG, (a measure of the process of thermal regulation) was significantly lower with Type H clothing during times awake and asleep (p < 0.01 andp < 0.05, respectively), but the increase of DPG during the sleep period was greater with Type H clothing (p < 0.01). Type H clothing was also associated with a significantly greater secretion of nocturnal urinary aMT-6s during the first half of sleep (p < 0.05). Sleeping Inventory tests indicated that the subjects with Type H clothing had better subjective scores for sleepiness, sleep initiation, and sleep maintenance (allp < 0.05), and slightly less worries (0.05 < p < 0.10). These results suggest that clothing type uncovering the extremities in a thermally neutral environment of 24 °C might induce a greater day-night variation in heat loss and a larger nocturnal increase in skin temperature in the distal regions and promote more sleepiness and a more rapid sleep onset via increased urinary aMT-6s secretion in the first half of sleep period. It is suggested that these changes might be related to the role of the sympathetic nervous system in thermoregulation and melatonin secretion. [ABSTRACT FROM PUBLISHER]

A pilot-scale two-step biofilter system was evaluated in treating food waste composting emission for 220 days. Wood chips were packed at the bottom section while mixture of rock wool and earthworm compost (6% w/v) was packed at the top section. Inlet ammonia concentration was found to be dominant and intermittent. The overall ammonia removal of over 98% was achieved, 70% of which was removed in the wood chip section. The highest ammonia elimination capacity was determined to be 39.43 g-NH3/m3/h at 99.5% removal efficiency. From biodegradation kinetic analysis, the maximum removal rate, Vm, of the wood chip section was determined to be 200 g-NH3/m3/h and the saturation constant, Ks, 180 mg/m3. For the rock wool-earthworm cast mixture section, the Vm was 87 g-NH3/m3/h and Ks was 87 mg/m3. Complete removal of hydrogen sulfide and most trace compounds were achieved by the biofilter. Highest hydrogen sulfide elimination rate was 0.22 g-H2S/m3/h. The biofilter was optimized from 24 to 16 s EBRT with resulting low average pressure drops of 16 and 29 mm H2O/m, respectively. [ABSTRACT FROM AUTHOR]

Abstract The purpose of this study was to determine whether the different thermal conditions of the arm and leg due to wearing different types of clothing during the afternoon could modulate the circadian rhythm of body temperature and subjective sleep quality. Six healthy female volunteers were studied twice with two types of clothing, leaving the arm and leg covered or uncovered. The environmental chamber was controlled at 24&ThickSpace;±&ThickSpace;0.5°C and 50&ThickSpace;±&ThickSpace;5% RH during wakefulness and 28&ThickSpace;±&ThickSpace;0.5°C and 50&ThickSpace;±&ThickSpace;5% RH during night sleep. One type of clothing consisted of long-sleeved shirts and full-length trousers (Type L, 989 g, 0.991 clo); the other type was of half-sleeved shirts and knee-length trousers (Type H, 750 g, 0.747 clo). One testing session lasted for 16 h from 14:00 to 06:00 h the next morning. Subjects wore Type L or Type H clothing during the afternoon exposure (14:00&ThickSpace;–&ThickSpace;19:00), and Type L clothing during the evening (19:00&ThickSpace;–&ThickSpace;22:30 h) and the night sleep (22:30&ThickSpace;–&ThickSpace;06:00 h). Results were as follows. (1) When wearing Type H rather than Type L clothing, skin temperatures of the arm and leg were significantly lower during the time of exposure, and increased more after the evening. (2) Rectal temperature was not significantly different between the two types of clothing except during the early part of the exposure period, but it decreased during the evening by a significantly greater amount when wearing Type H clothing. (3) Subjective sleep quality was not significantly different between the two clothing types. These results suggest that afternoon exposure of the arm and leg to a slightly cool environment does not have a strong after-effect on the body temperature and subjective sleep quality. [ABSTRACT FROM AUTHOR]