Effects of weather variables on thermoregulation of calves during periods of extreme heat
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To determine effects of ambient temperature, relative humidity, wind speed, relative barometric pressure, and temperature-humidity index (THI) on nasal submucosal and rectal temperatures in cattle during extreme summer conditions.20 black crossbred beef heifers (mean body weight, 217.8 kg).Nasal submucosal and rectal temperatures were monitored every 2 hours for 24 hours on 3 nonconsecutive days when ambient temperature was forecasted to exceed 32.2°C. Ambient temperature, relative humidity, wind speed, and relative barometric pressure were continuously monitored at a remote weather station located at the research facility. The THI was calculated and used in the livestock weather safety index (LWSI). Relationships between nasal submucosal or rectal temperature and weather variables were evaluated.Nasal submucosal and rectal temperatures were related to all weather variables monitored. A positive relationship was determined for ambient temperature and THI with both nasal submucosal and rectal temperatures. A negative relationship was evident for nasal submucosal and rectal temperature with relative humidity, wind speed, and relative barometric pressure. Nasal submucosal and rectal temperatures increased with increasing severity of LWSI category.Effects of environmental conditions on thermoregulation in calves exposed to extreme heat were detected. The positive relationship between nasal submucosal temperature and ambient temperature and THI raised concerns about the efficacy of intranasal administration of temperature-sensitive modified-live virus vaccines during periods of extreme heat. Environmental conditions must be considered when rectal temperature is used as a diagnostic tool for identifying morbid cattle.Keywords:
Rectal temperature
Heat index
Apparent temperature
Heat index
Apparent temperature
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This paper is aimed at introducing the findings from our measurement and investigation on the high temperature and humidity environment for paper-making plants.In hoping to find out the distribution regularity between the temperature and humidity in the papermaking workshops with hot and humid environment,we have carried out field measurements and investigations of five paper-making plants in different regions all over the country in different seasons.The results of our measurements and analysis reveal some regular results between the temperature and the height of the workshop buildings of such paper-making plants.To be exact,conclusions have been made that the temperature in such buildings increases with the height vertically no matter whether in summer or in winter,but the temperature in summer rises much more remarkable in comparison with that in winter.Moreover,a comparative formula has been derived with the increase of the height as compared with that of the temperature.However, the formula is just applicable for a building height below six meters.In addition,we have also worked out the relative humidity and the humidity ratio to the comparative temperature.Actually,the relative humidity and humidity ratio can be taken as the hierarchical distribution features,though they are not entirely in proper ratio to each other,for the temperature is not only related to the humidity but also to the temperature change.In some ways,it can be said that the higher the temperature,the lower the relative humidity with the humidity ratio being constant.Furthermore,both the relative humidity and humidity ratio distribution characteristics are closely related to the moisture diffusion degree and the mode of paper machines in the workshops.And,finally,we have also made believe that such a kind of hot and humid environment is harmful for the workers to stay long. In one word,the above investigation and analysis have done on temperature and humidity distribution characteristics are expected to provide an important reference for designing better ventilation conditions in such plants so as to improve better working environment both for the workers and for working machines.
Apparent temperature
Critical relative humidity
Papermaking
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Local humidity and temperature monitoring of ground parking aircraft were carried out in this study. Changes in the humidity of different bays and the relationship between local humidity and local temperature were investigated. Moreover, the concept as well as a method of calculating the humidity characteristic coefficient (HCC) were put forward, and two models of aircraft local humidity were established using the humidity and temperature of the thermometer shelter as arguments. Furthermore, bays of an airplane were divided into three groups according to differences in local humidity, and the range of the HCC of each group were determined. The results suggest that the rates of change of local humidity and local temperature are negatively correlated, moreover, the theoretical model shows a linear relationship between humidity and temperature, with a negative slope suggesting changes in humidity are inversely proportional to temperature. The ratio of the local environment slope to the external environment slope has a constant value. Finally, bay sealing and temperature features were found to significantly affect local humidity, and average deviations between the monitored humidity and humidity values predicted using the two temperature models were all less than, or equal to, 7.3% relative humidity.
Apparent temperature
Critical relative humidity
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Rectal temperature
Mediator
Anterior hypothalamus
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Heat index
Feedlot
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Abstract Monitoring and understanding the variability of heat within cities is important for urban planning and public health, and the number of studies measuring intraurban temperature variability is growing. Recognizing that the physiological effects of heat depend on humidity as well as temperature, measurement campaigns have included measurements of relative humidity alongside temperature. However, the role the spatial structure in humidity, independent from temperature, plays in intraurban heat variability is unknown. Here we use summer temperature and humidity from networks of stationary sensors in multiple cities in the United States to show spatial variations in the absolute humidity within these cities are weak. This variability in absolute humidity plays an insignificant role in the spatial variability of the heat index and humidity index (humidex), and the spatial variability of the heat metrics is dominated by temperature variability. Thus, results from previous studies that considered only intraurban variability in temperature will carry over to intraurban heat variability. Also, this suggests increases in humidity from green infrastructure interventions designed to reduce temperature will be minimal. In addition, a network of sensors that only measures temperature is sufficient to quantify the spatial variability of heat across these cities when combined with humidity measured at a single location, allowing for lower-cost heat monitoring networks. Significance Statement Monitoring the variability of heat within cities is important for urban planning and public health. While the physiological effects of heat depend on temperature and humidity, it is shown that there are only weak spatial variations in the absolute humidity within nine U.S. cities, and the spatial variability of heat metrics is dominated by temperature variability. This suggests increases in humidity will be minimal resulting from green infrastructure interventions designed to reduce temperature. It also means a network of sensors that only measure temperature is sufficient to quantify the spatial variability of heat across these cities when combined with humidity measured at a single location.
Heat index
Urban Heat Island
Apparent temperature
Public Health Interventions
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Rectal temperature
Skin Temperature
Mean radiant temperature
Fowl
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Key Points Fever is a homeostatic response under thermoregulation.Hyperthermia, by contrast, is an increase in body temperature from conditions that overwhelm thermoregulation.By consensus, fever is defined as a rectal temperature ≥38°C (100.4°F).The treatment of fever itself is less important than the identification of its cause.
Rectal temperature
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Apparent temperature
Air humidity
Environmental chamber
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