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Facial skin temperature has been applied to evaluate thermal comfort in a few studies, but the related theoretical basis is not sufficient. We conducted a climate‐controlled experiment in winter. The air temperatures were 12, 15, 18, 21, and 24°C, and the relative humidity was set to 60%. During exposure (140 min), the subjects were in a sedentary state, and their thermal sensation, comfort, and acceptability of perceived thermal environments were documented many times. iButton instruments were used to continuously and automatically record skin temperatures on the forehead, nose, right ear, right cheek, left cheek, left ear, and chin. The measurement accuracy of the corrected skin temperature was within 0.1°C after calibrating each i‐Button. The experimental results showed that the skin temperatures at different measurement points varied significantly. The forehead skin temperature was the highest, whereas the nose, being the facial part, exhibited the lowest skin temperature (except 24°C). The uneven degree of the skin temperature distribution increased as air temperature decreased. Correlation analysis confirmed that the facial skin temperature can be used to evaluate thermal sensation. Nose skin temperature and the average skin temperature of the forehead, nose, and chin are the most suitable indicators of thermal sensation. The correlation between facial skin temperature and the thermal sensation was significantly higher after 15 min of exposure time than that during 0–15 min. This study provides a theoretical basis for using facial skin temperature to dynamically monitor thermal sensations. [ABSTRACT FROM AUTHOR]

A method to develop an adaptive thermal comfort model based on the running mean outdoor temperature for Chinese people was proposed. The determination of two important parameters (neutral temperature and outdoor temperature) in the adaptive thermal comfort model was the focus of this work. A longitudinal survey was conducted from Jan. 2010 to Feb. 2011 in two naturally ventilated office buildings located in Changsha, China. During the survey, the thermal sensation of the subjects was investigated, and the indoor temperature was measured daily. Based on the field data, the neutral temperature and the running mean outdoor temperature were determined. Further, an adaptive thermal comfort model was established by quantifying the relationship between the neutral temperature and the running mean outdoor temperature. The results show that the adaptive thermal comfort model based on the running mean outdoor temperature can well reflect the change of neutral temperature in the two office buildings with the climate of Changsha China. This study provides a reliable method to adjust the adaptive thermal comfort model based on the running mean temperature for Chinese people. [ABSTRACT FROM AUTHOR]

This study investigated the effects of four important microclimate parameters on outdoor thermal sensation and neutral temperature. A long term (almost 2 years) field investigation was conducted at six typical public spaces in Changsha China, with hot-summer and cold-winter climate. During a single investigation of one day (from 9:00 to 18:00), outdoor air temperature, air humidity, global temperature and wind speed were continuously measured at one measuring point. People visiting the public spaces (near the measuring site) were randomly invited to fill out a questionnaire describing their feelings of thermal comfort and other important psychological factors. Based on the field data (7851 samples), relationship between people’s outdoor thermal sensation and the microclimate parameters were quantified. Further, the effect of the microclimate parameters on outdoor thermal sensation and neutral temperatures was analyzed. The results revealed that outdoor microclimate parameters, especially outdoor air temperature, play important roles on outdoor thermal sensation when people stay outdoors. The variation in outdoor microclimate parameters led to the biggest change of outdoor neutral temperature in winter. Seasonal and regional differences in outdoor neutral temperature were found, which reflects different thermal comfort requirements under distinct outdoor microclimate conditions. [ABSTRACT FROM AUTHOR]

Abstract: This study proposed a method to determine time period of thermal adaption for occupants in naturally ventilated building, and analyzed the synergistic and separate feedback effect of the physical and psychological adaption modes on the time period of thermal adaption. Using the method, the values of the time period of thermal adaption were obtained on the basis of the data from a long-term field survey conducted in two typical naturally ventilated offices located in Changsha, China. The results showed that the occupants need to take 4.25 days to fully adapt to a step-change in outdoor air temperature, under the synergistic feedback effect of the physical and psychological adaption modes. The time period of thermal adaption increased to 13 days, if only the feedback effect of the physical adaption mode was accounted for. The difference between the two values of the time period of thermal adaption indicated that the psychological adaption mode can speed up the process of thermal adaption to the variation in the outdoor climate condition. This study presented a new insight into the feedback from the thermal adaption modes to occupant thermal comfort. [Copyright &y& Elsevier]

Prevalence of allergic rhinitis has rapidly increased among Chinese children, but the reasons are unclear. Recent findings have suggested that exposure to outdoor air pollutants may increase the risk of allergic rhinitis, but the results were inconsistent. This study further investigated the effect of outdoor air pollutants on allergic rhinitis among preschool children. A standardized questionnaire on health, home and environmental factors was conducted for 4988 children aged 1–8 in the city of Changsha, and the concentrations of PM 10 (particle diameter ⩽10 μm), sulfur dioxide (SO 2) and nitrogen dioxide (NO 2) during 2006–2011 were acquired from the official web of Changsha Environmental Protection Agency. Results showed that the prevalence of children’s doctor diagnosed rhinitis was 8.4% (95% confidence interval [CI] 7.0%–10.0%). It was found that the prevalence of rhinitis was not associated with site-specific background concentrations of air pollutants, but significantly positively correlated with age-related accumulative personal exposure of PM 10, SO 2 and NO 2. We conclude that age-related accumulative personal exposure to ambient air pollution may play an important role in the development of rhinitis. [ABSTRACT FROM AUTHOR]

Abstract: The present study gave a comprehensive insight into the relationship between human thermal adaptive behaviour and the change of climate conditions. A long-term survey was carried out from Jan. 2010 to Feb. 2011 in two naturally ventilated offices, located in Changsha, China. During the survey, occupants’ thermal adaptive behaviour (use of various controls) was investigated daily. The controls included window, door, curtain, fan, hand heater and air-conditioner. Relativity analysis indicated that outdoor air temperature is the most important climate parameter that caused the use of controls. The effects of outdoor air temperature on the use of each control were further analyzed from three aspects: usage proportion, usage degree and transition of control state. Based on the analysis, the characteristics of the thermal adaptive behaviour in the offices were revealed. And also, the differences between the two offices located in different types of building were discussed. The results of this study are helpful to adapt the built environment in naturally ventilated buildings to the change of climate conditions. [Copyright &y& Elsevier]

Clothing adjustment is an essential way for people to adapt to the weather changes and maintain thermal comfort in an outdoor environment. In this study, it was assumed that outdoor clothing adjustment was influenced by the local past temperatures. With temperature changes, clothing adjustment could be divided into "free adjustment phase" and "restricted adjustment phase". Two consecutive years of outdoor field investigation experiments were conducted in 6 typical outdoor spaces in Changsha, China, which was hot in summer and cold in winter. During the field experiment, outdoor thermal environment parameters were measured in real-time, meanwhile, clothing and thermal comfort of participants were documented. The analysis results of field experiment data verified the assumption. 7876 effective samples were collected to build a creative outdoor clothing model (OCM) considering the weather characteristics of Changsha based on running mean temperature and four-parameter logistic function. The determination coefficient (R 2) of the OCM was 0.954, which was higher than the existing models. Moreover, prediction deviations were within 20% for 86% samples. According to the OCM, the range of running mean temperature corresponding to the free adjustment phase was 4 °C–24 °C for the Changsha residents. The free changes of clothing insulation during this phase enabled people to maintain thermal comfort in the outdoor environment. The OCM proposed in this study can provide a theoretical basis for evaluating outdoor thermal comfort and wearing appropriately according to the temperature. ● Clothing adjustment is the most essential means of thermal adaptation outdoors ● Outdoor clothing adjustment is influenced by the local past temperatures ● Clothing adjustment was divided into free and restricted adjustment phases ● A logistic function clothing model was proposed based on running mean temperature ●Clothing adjustment has a feedback effect on thermal comfort in outdoor environment [ABSTRACT FROM AUTHOR]

Background: Evidence is scarce on the trend in prevalence of physical frailty in China; the primary purpose of this study was to identify the prevalence and correlates of physical frailty among older nursing home residents in China.Methods: Cross-sectional study in 20 nursing homes in Changsha, China. Physical frailty was defined based on the frailty phenotype including weight loss, low grip strength, exhaustion, slow gait speed, and low physical activity. Participants with at least three affected criteria were defined as being frail. Participants with one or two affected criteria were considered as pre-frail, and those with no affected criteria were considered as robust. A total of 1004 nursing home residents aged 60 and over were included in this study. A multinomial logistic regression model was used to analyze the associations of physical frailty with its potential risk factors, including age, sex, education levels, marital status, type of institution, living status, current drinking, current smoking, regular exercise, and self-reported health.Results: The overall prevalence of physical frailty and prefrailty was 55.6, and 38.5%, respectively. The rate of physical frailty substantially increased with age, and was higher in women than in men (69.5% vs. 30.5%). The multinomial logistic regression analysis showed that older age, being women, living in a private institution, living alone or with unknown person, having no regular exercise (≤ 2 times/week), and poor self-reported health were significantly associated with increased odds of being physically frail.Conclusion: We demonstrated physical frailty is highly prevalent among older residents in nursing homes in China, especially in women. The potential role of those associated factors of physical frailty warrant further investigations to explore their clinical application among elderly nursing home residents. [ABSTRACT FROM AUTHOR]

• A dynamic setting temperature that adapts to climate change was proposed. • The method was based on clothing adjustment behavior which adapts to thermal comfort. • The dynamic setting temperature had significant energy saving potential. • The dynamic setting temperature is useful for intelligent control of air-conditioner. Saving energy consumption of air-conditioning is essential to building energy conservation while satisfying the thermal comfort requirements of indoor environment. On the basis of human clothing adjustment behavior, a dynamic setting temperature (DST) that adapts to climate change was proposed in this paper, i.e. indoor air-conditioning setting temperature changes dynamically with outdoor air temperature; furthermore. A method was established to obtain the DST. The daily mean clothing insulation was predicted according to the historical temperature at first, then indoor thermal comfort temperature was calculated based on the variable clothing insulation, and finally the DST was determined. According to the value or range of predicted mean vote (0, -0.5~0.5, -1~+1) corresponding to the thermal comfort, three levels of DST were defined. The corresponding thermal acceptability rates were 95%, 90% and 73%, respectively. A simulation of DST was conducted in a public building in Changsha, China based on meteorological data of 2017. Three levels of DST ranges were obtained, varied from 20.1 to 27.8 °C in level I, 17.8 to 28.7 °C in level II and 15.4 to 29.7 °C in level III, respectively. The simulation results of operational air-conditioning energy consumption shows that the application of DST could save up to 65.5% of energy consumption compared with the traditional fixed setting temperature (FST), and the operational energy consumption decreased by 59.1% due to the application of level-III DST compared with level-I DST. Therefore, the DST proposed in this paper has significant energy saving potential while meeting the thermal comfort requirements. [ABSTRACT FROM AUTHOR]

Background: FRAIL-NH has been commonly used to assess frailty in nursing home residents and validated in many ethnic populations; however, it has not been validated in mainland China, where such an assessment tool is lacking. This study aimed to (1) assess the discriminatory performance of FRAIL-NH in two-class frailty (non-frail+ pre-frail vs. frail) and three-class frailty (non-frail vs. pre-frail vs. frail), based on the Frailty Index (FI), (2) determine the appropriate cutoff points for FRAIL-NH that distinguish two-class and three-class frailty, and (3) examine the agreement in classification between FRAIL-NH and FI.Methods: A cross-sectional study of 302 residents aged 60 years or older from six nursing homes in Changsha was conducted. The FRAIL-NH scale and 34-item FI were used to measure frailty. Two-way and three-way receiver operating characteristic (ROC) curves were used to estimate the performance of FRAIL-NH. Cohen's Kappa statistics were used to examine the agreement between these two measures.Results: The agreement between FRAIL-NH and FI ranged from 0.33 to 0.55. Regardless of what FI cutoff points were based on, the volume under the ROC surface (VUS) for FRAIL-NH from the three-way ROC were higher than the VUS of a useless test (1/6), and the area under the ROC curve (AUC) for FRAIL-NH from the two-way ROC were higher than the clinically meaningless value (0.5). When using FI cutoff points of 0.20 for pre-frail and 0.45 for frail, FRAIL-NH cutoff points of 1 and 9 in classifying three-class frailty had the highest VUS and the largest correct classification rates. Whichever FI was chosen, the performance of FRAIL-NH in distinguishing between pre-frailty and frailty, and between non-frailty and pre-frailty was equivalent. According to FRAIL-NH, the proportion of individuals with frailty misclassified as pre-frailty was higher than that of individuals with non-frailty misclassified as pre-frailty.Conclusion: FRAIL-NH can be used as a preliminary frailty screening tool in nursing homes in mainland China. FI should be further used especially for those classified as pre-frailty by FRAIL-NH. It is not advisable to simply combine adjacent two classes of FRAIL-NH to create a new frailty variable in research settings. [ABSTRACT FROM AUTHOR]

This study explored the facial skin temperature and thermal sensation of sub-tropically acclimated subjects in summer. We conducted a summer experiment that simulated the common indoor temperatures in Changsha, China. Twenty healthy subjects experienced five exposure conditions: 24, 26, 28, 30 and 32 °C with a relative humidity of 60%. During exposure (140min), the sitting participants documented their thermal sensation, comfort and acceptability of the environment. Their facial skin temperatures were continuously and automatically recorded by using iButtons. These facial parts include the forehead, nose, left and right ears, left and right cheeks and chin. The results found that the maximum facial skin temperature difference increased with air temperature reduction. The forehead skin temperature was the highest. Nose skin temperature is lowest when air temperature is not higher than 26 °C during summer. Correlation analysis confirmed that the nose is the potential facial part that is most suitable to evaluate thermal sensation. Based on the published winter experiment, we further explored their seasonal effects. The seasonal analysis showed that, compared with winter, thermal sensation is more sensitive to indoor temperature changes and facial skin temperatures were less susceptible to thermal sensation changes in summer. Facial skin temperatures were higher in summer under the same thermal conditions. It suggests that seasonal effects should be considered when facial skin temperature can be used as an important parameter for indoor environment control in the future through monitoring thermal sensation. • Uneven degree of skin temperature distribution rises with reducing air temperature. • Nose is the most potential facial part for thermal sensation prediction. • Facial skin temperatures were higher in summer than that in winter. • Thermal sensation is more susceptible to air temperature changes in summer. • Facial skin temperatures were less sensitive to thermal sensation changes in summer. [ABSTRACT FROM AUTHOR]