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This study aims to evaluate agreement among subjective thermal comfort, thermal sensation, thermal perception, and thermal tolerance indices, according to pedestrians in downtown Santa Maria, southern Brazil, which has a humid subtropical climate (Cfa). Between August 2015 and July 2016 (three periods), 1728 questionnaires were applied. Evaluation of the dependence of statistical variables was based on gender and age, at three periods of time: August 2015 (864 respondents), January 2016 (432 respondents), and July 2016 (432 respondents). Statistical evaluation was based on Pearson's chi-square test using RStudio software, and a significance level (α) of 5% for thermal comfort, thermal sensation, thermal preference, and thermal tolerance was used. Results indicated that age and gender affect the relationship between the variables. Thermal comfort and thermal tolerance presented the best correlation and coherence, regardless of age or gender. This study contributes to knowledge on the local microclimate and can contribute to urban planning to implement strategies that improve pedestrians' thermal comfort.

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Outdoor thermal comfort (OTC) surveys require synchronous monitoring of meteorological variables for direct comparisons against subjective thermal perception. The Universal Thermal Climate Index (UTCI) is a feasible index as it integrates meteorological conditions as a single value irrespective of urban morphological attributes or biological sex, age and body mass. ERA5-HEAT (Human thErmAl comforT) is a downloadable reanalysis dataset providing hourly grids of UTCI climate records at 0.25° × 0.25° spatial resolution from 1979 to present. We here evaluate for the first time whether it is possible to use ERA5-HEAT data as a proxy for the UTCI measured onsite during OTC surveys. A dataset comprising 1640 survey responses gathered over 14 OTC campaigns in Curitiba, Brazil (25°26'S, 49°16'W) was analysed. We assessed the bias obtained between the Dynamic Thermal Sensation, an index derived from the UTCI, and the thermal sensation reported by survey participants by considering locally measured meteorological variables and ERA5-HEAT reanalysis data. As ERA5-HEAT data are given on an hourly basis, prediction bias can be greatly reduced when accounting for survey responses close to the hour. In terms of seasons, the fall and winter seasons have diminished mean bias, though with larger spread than in summer. In terms of UTCI stress categories, prediction bias is lower for the thermal comfort range. When comparing reanalysis data against WMO station data as proxy candidates for survey field data, the former presented lower bias, less spread in terms of standard deviation and higher correlation to in situ data.

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This dataset was compiled to estimate the levels of thermal comfort and mental health in a sample group of university students confined due to the COVID-19 pandemic. By the time research was carried out, these students of a hot and humid region of Mexico, had already spent 200 days on distance learning using online platforms. A total of 324 records were documented with a final sample of 316 valid participants. The total records were collected directly from the students through a web platform (Microsoft forms). This data set can be used to generate correlations between mental health, thermal comfort, and individual characteristics in the study population that will allow to identify the influence of the built environment and local climate on the levels of stress and anxiety that university students experienced under confinement. It can also be used to issue recommendations to improve the quality of built spaces and for the construction of adaptive models of thermal comfort considering mental health as a study variable.

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With the aging of the human body, some physiological changes occur, compromising thermoregulatory mechanisms, negatively influencing the individual's thermal sensation. Given this fact, the present study aimed to build a predictive model to determine the thermal sensation index for elderly people (TSIEP) in a hot climate region, considering their sensitivity in the perception of climate change in the city of Campina Grande, in the semi-arid region of Paraíba/Brazil. For this purpose, an observational study was carried out from April to December 2016 with elderly people inside their homes. The responses of the sample units (elderly people) to the categories of thermal sensation (hot, comfortable, and cold) were transformed into probit estimates, and, using the multivariate modeling statistical technique (canonical correlation), the TSIEP was determined. Finally, TSIEP showed that the thermal sensation of elderly people residing in Campina Grande tends to be more sensitive to cold and less sensitive to heat.

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I was evaluated the effect of seven different combinations of temperature, air velocity, and relative air humidity on the frequency and duration of eating, drinking, resting, cannibalism, dust bathing, scratching, ground pecking, shivering, and stretching behaviors of turkeys at three different ages. The combinations tested of temperature, relative air humidity, and air velocity were, respectively: 1 (22 °C, 50%, 1 m/s); 2 (26.2 °C, 73.2%, 0.45 m/s); 3 (26.6 °C, 71.2%, 1 m/s); 4 (28.9 °C, 72%, 1.4 m/s); 5 (31.1 °C, 85%, 0.45 m/s); 6 (34.1 °C, 82.1%, 1 m/s); and 7 (34.4 °C, 82.1%, 1.4 m/s) for three ages of birds (61, 96, and 131 days of age). Seven birds were housed per pen, at a density of 3 males/m2, totaling 147 birds in the entire experiment. Each combination was applied for 5 days. The data were analyzed considering the number of times the bird performed the behavior and the time it performed (in seconds). Each pen was considered a repetition. A comparison of the medians was used to compare the treatments by each age. The results showed that young birds were more likely to suffer from the combination of low temperature and high air velocity, reducing their frequency of normal behaviors. Increased humidity at a low temperature raised the frequency of scratching, shivering, and cannibalism behaviors leading to poorer bird welfare. It is recommended that the temperature, relative air humidity, and air velocity combination of 26.6 °C; 71.2%; and 1 m/s, respectively, for young birds, and 22 °C; 50%; and 1 m/s, respectively, for older birds should be used.

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The present study carried out assessments regarding thermal sensations under different weather conditions in three urban areas in Cuiabá, Brazil, a Tropical Savannah climate (Aw) region. Thermal acceptability by means of thermal sensation votes (TSV) was addressed based on the estimation of the Universal Thermal Climate Index (UTCI) values. Important issues related to clothing thermal insulation (Icl), the effect of gender on thermal sensation, and implications of artificial conditioning (AC) systems are also evaluated. Micrometeorological variables were determined and 685 questionnaires were applied to evaluate individual pedestrian thermal preferences. The Icl observed in the Tropical climate was lower than that intrinsically inputted by the UTCI for Temperate climates. The local thermal comfort zone ranged between 21.5 and 28.5 °C, with both thresholds higher than those observed in studies conducted in Subtropical, Mediterranean, and Continental Temperate climates while the local hot thermal sensation categories were displaced at least 3 °C above than those for the aforementioned climates. The effect of gender on thermal sensation indicated that females are more sensitive to cold stress conditions than males, requiring higher Icl for temperatures below 28 °C. The physiological adaptation by continuous exposure to AC systems reduced the neutral temperature between AC and non-artificial conditioning system users (NAC) by 0.8 °C, with more intense differences in hot TSV ranges. This study reveals differences between stated TSV classes derived for other climates and those resulting from TSV declared by Savannah local residents, indicating that local thermal sensation scale for UTCI in an important key for environment planning.

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The objective of this study was to evaluate the effects of different environment conditions on productive performance and surface temperatures of Japanese quail (Coturnix coturnix japonica) during the initial stage of laying. In environmental controlled chambers, the birds were subjected to different temperatures and air velocities at the feeder. A total of 216 Japanese quails were distributed randomly in 2 galvanized wire cages, with 3 partitions each and 27 birds/cage. The experimental design consisted of randomized blocks with 2 treatments (air velocity at the feeder: 0, 1, 2, and 3 m/s and air temperature: 17, 23, 29, and 35°C) and 6 replicates. The productive performance was analyzed statistically (Sigma Plot 12.0) by 2-way ANOVA, with treatment means separated by the Tukey test (P < 0.05). To evaluate the main effects and interactions of the factors, the Holm-Sidak multiple comparisons test was performed using a mild condition as the control group (0 m/s). Feed intake did not differ (P > 0.05) among birds reared at temperatures of 23, 29, and 35°C, but higher feed intake was noted at 17°C. The mean values of egg production increased significantly (P < 0.05) with increased air velocity levels. It was observed that there was an increase in egg production and feed intake with the intensification of air velocity at the feeder, regardless of ambient temperature. Egg weight and feed conversion were not affected by air velocity treatments (P > 0.05). There was a significant positive correlation between air temperature and mean surface temperature and head surface temperature. In contrast, a significant negative correlation was observed between air velocity and mean surface temperature and head surface temperature. Productive performance was affected by temperature and air velocity, except for egg weight and feed conversion, which was not influenced by air velocity. Air velocity is important in removing heat from the surface of birds.

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Brazil was rated the fourth leading producer and exporter of pork meat in the world. The aim of this study was to evaluate the temperature of the hands of pig slaughterhouse workers and its relation to the thermal sensation of the hands and the use of a cutting tool. The study included 106 workers in a pig slaughterhouse. An infrared camera FlirThermaCAM E320 (Flir Systems, Wilsonville, OR, USA) was used to collect the images of the dorsal and palmar surfaces of both hands. A numerical scale was used to obtain the thermal sensation. Chi-square test, Pearson correlation and Student's t test or Wilcoxon were used (p ≤ 0.05). The majority of workers felt cold in the hands (66%) and workers who used the knife felt the coldest. There was an association between the thermal sensation and the use of knife (p = 0.001). Workers who used the tool showed correlation between the thermal sensation and the temperatures of the left fingers, with a difference between the temperatures of the right and left hands of those who used the knife (p ≤ 0.05). The hands (left) that manipulated the products presented the lowest temperatures. Findings indicate that employers of pig slaughterhouses should provide gloves with adequate thermal insulation to preserve the health of workers' hands.

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In Brazil, the test that uses test tubes filled with cold water (25ºC) and tubes filled with water heated to a temperature of 45ºC is recommended by the Ministry of Health as a way of evaluate thermal sensitivity on the injured skin of leprosy patients. The purpose of this work was to quantify the thermal stimulation applied to the skin, as well as the temperature variation of the heated water and of the tube's outer surface during stimulation sessions. The experiment had the participation of 14 healthy volunteers (31.2±11.4 years-old), ten of which were male (33.1±13.5 years-old) and four were female (26.5±4.7 years-old). Three consecutive stimulation sessions were carried out, each of them with four stimuli. The maximum skin temperature at the end of the stimuli was measured at 35.8±0.6ºC. Such temperature values may be useful in the assessment of the loss of small fibers, which are responsible for the sensation of warmth.

No Brasil, o teste que utiliza tubos de ensaio preenchidos com água aquecida (45ºC) e resfriada (25ºC) é preconizado pelo Ministério da Saúde como forma de avaliar a sensibilidade térmica nas lesões de pele de pacientes com hanseníase. O objetivo deste trabalho foi quantificar o estímulo térmico na pele e a variação das temperaturas da água aquecida e da superfície externa do tubo, durante as sessões de estimulação. O experimento contou com 14 voluntários saudáveis (31,2±11,4 anos), sendo dez do gênero masculino (33,1±13,5 anos) e quatro do gênero feminino (26,5±4,7 anos). Realizaram-se três sessões seguidas de estimulação com quatro estímulos em cada sessão. A temperatura registrada na pele, ao final dos estímulos, apresentou diferenças entre as sessões, atingindo o máximo de 35,8±0,6ºC. Estes valores de temperatura podem ser úteis na avaliação da perda de fibras finas responsáveis pela sensação de aquecimento.

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