• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.10
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• pp.1073-1084
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• 2010

In this paper, the bio-heat equation including thermoregulatory functions is solved for an anatomically based human head model comprised of 14 tissues to study the thermal implications of high-power exposure to electromagnetic(EM) fields due to half-wave dipole antenna both at 835 and 1,800 MHz. The dipole antenna is located at the side of the ear and the front of the eyes. The FDTD method has been used for the SAR computation. When solving the BHE, the thermoregulation function and sweating effetecs are included in order to predict more exact temperature increase. It is noted that an approximately proportional relationship between the tissues and the maximum temperature increase and the antenna power is not maintained when the thermoregulation and sweating effects are fully accounted for under high power exposure.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.7
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• pp.965-970
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• 1999

This study was conducted to investigate the thermoregulatory characteristics of feet and legs by comparing with the physiological responses according to the covering parts of lower limbs. Five healthy female subjects wore three types of clothing-covered legs and feet(LF-C) with long trousers and socks exposed the legs(L-E) with half trousers and socks and exposed the legs and feet(LF-E) with only half trousers-when the subjects rested at $25^{\circ}C$ and were exposed to 18$^{\circ}C$ for 90 min. Rectal temperatures (Tre) were maintained higher in LF-E than L-E and LF-C at both environments. Decreases of The after exposure to 18$^{\circ}C$ were significantly smaller in LF-E than L-E and LF-C and almost same in L-E and LF-C Heat production in both environments increases of heat production and weight loss after exposure to 18$^{\circ}C$ were not significant among three types of clothing. From these findings it would be suggested that the legs would play the little role of voluntary thermoregulation as vasoconstriction and the role of the legs depend on thermal conditions of feet while the feet play the positive role of voluntary thermoregulation in terms of heat conservation in cool environment.

• Journal of the Korean Home Economics Association
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• v.39 no.5
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• pp.39-47
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• 2001

The purpose of this study was to investigate two different kinds of t-shirts on thermal responses at air temperature of $23{\pm}2^{\circ}C$, relative humidity of $70{\pm}5%$ and wind velocity not more than 0.5 m/sec. Five healthy men wearing boxy type t-shirts or fitted type t-shirts, participated as the subjects. Rectal temperature, skin temperatures, heart rate, clothing microclimate and subjective sensation were measured every 2 minute during experiment(rest, walking, recovery each 20 min.) and compared between two experimental garments(boxy type and fitted type t-shirts). Rectal temperature was lower in recovery phase at wearing fitted type t-shirts. Chest skin temperature was higher at wearing fitted type t-shirts and thigh and leg skin temperature were higher at wearing boxy type t-shirts.

• Journal of Animal Science and Technology
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• v.65 no.4
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• pp.683-697
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• 2023

The threat posed by increased surface temperatures worldwide has attracted the attention of researchers to the reaction of animals to heat stress. Spermatogenesis in animals such as stallions is a temperature-dependent process, ideally occurring at temperatures slightly below the core body temperature. Thus, proper thermoregulation is essential, especially because stallion spermatogenesis and the resulting spermatozoa are negatively affected by increased testicular temperature. Consequently, the failure of thermoregulation resulting in heat stress may diminish sperm quality and increase the likelihood of stallion infertility. In this review, we emphasize upon the impact of heat stress on spermatogenesis and the somatic and germ cells and describe the subsequent testicular alterations. In addition, we explore the functions and molecular responses of heat shock proteins, including HSP60, HSP70, HSP90, and HSP105, in heat-induced stress conditions. Finally, we discuss the use of various therapies to alleviate heat stress-induced reproductive harm by modulating distinct signaling pathways.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.988-994
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• 2008

The purpose of the investigation was to establish how the pineal-adrenal axis plays an important role in thermoregulation in female goats under short-term heat stress. The study was conducted to observe the influence of glucocorticoids on pineal function in goats and its influence on stress alleviation capability. Melatonin and glucocorticoid secretions and several other endocrine and biochemical blood parameters reflecting the animals well being were determined over a one week period after goats had been exposed to $40^{\circ}C$ and 60% relative humidity for 10 days. Six female goats were used in the study. These animals served as self controls prior to the start of the experiment. The study was conducted for a period of seventeen days in a psychrometric chamber at $40^{\circ}C$ and 60% relative humidity. Chemical pinealectomy was achieved using propranolol followed by exogenous hydrocortisone treatment. Blood samples were drawn twice daily after each treatment to find the effect of hydrocortisone on plasma glucose, total protein, total cholesterol, cortisol, insulin, aldosterone, melatonin and corticosterone. Chemical pinealectomy significantly ($p{\leq}0.05$) affected plasma levels of the parameters studied and these could be significantly ($p{\leq}0.05$) counteracted by administration of hydrocortisone. Chemical pinealectomy aggravated thermal stress, although administration of hydrocortisone could ameliorate the condition. This indicated a role of the pineal in support of thermoregulation. The study establishes the modulating effect of glucocorticoids on pineal activity to relieve thermal stress in goats.

• Journal of Animal Science and Technology
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• v.62 no.2
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• pp.141-158
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• 2020

Skin is a major thermoregulatory organ in the body controlling homeothermy, a critical function for climate adaptation. We compared genes expressed between tropical- and temperate-adapted cattle to better understand genes involved in climate adaptation and hence thermoregulation. We profiled the skin of representative tropical and temperate cattle using RNA-seq. A total of 214,754,759 reads were generated and assembled into 72,993,478 reads and were mapped to unique regions in the bovine genome. Gene coverage of unique regions of the reference genome showed that of 24,616 genes, only 13,130 genes (53.34%) displayed more than one count per million reads for at least two libraries and were considered suitable for downstream analyses. Our results revealed that of 255 genes expressed differentially, 98 genes were upregulated in tropically-adapted White Fulani (WF; Bos indicus) and 157 genes were down regulated in WF compared to Angus, AG (Bos taurus). Fifteen pathways were identified from the differential gene sets through gene ontology and pathway analyses. These include the significantly enriched melanin metabolic process, proteinaceous extracellular matrix, inflammatory response, defense response, calcium ion binding and response to wounding. Quantitative PCR was used to validate six representative genes which are associated with skin thermoregulation and epithelia dysfunction (mean correlation 0.92; p < 0.001). Our results contribute to identifying genes and understanding molecular mechanisms of skin thermoregulation that may influence strategic genomic selection in cattle to withstand climate adaptation, microbial invasion and mechanical damage.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 1994.10a
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• pp.5-25
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• 1994

The purpose of this paper is to provide the thermal comfort for humans using physiological principles of heat transfer and thermoregulation, heat exchange between the human body and its enclosur, and heat exchange between the inside enclosure and the outside environment.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.2
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• pp.201-205
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• 1997

An experiment has been conducted to compare the sweating rate between male and female Bali cattle under tropical conditions in Bali, Indonesia with dry bulb (DB) temperatures varying from 25 to $34.5^{\circ}C$ and relative humidity (RH) 70 to 98%. Rectal temperature (Tr) was significantly different (p < 0.05) between males and females (39.7 vs $39.4^{\circ}C$ compared to 39.2 vs $38.8^{\circ}C$ on weeks 1 and 8 respectively). There were significant effects on RR associated with both $week{\times}sex$ (p < 0.01) and $sex{\times}time$ (p < 0.01) interactions, with values for males higher than females. Skin temperature (Ts) differed significantly between sexes (p <0.05), weeks (p < 0.05) and times (p < 0.01); being lower in females (36 vs $36.4^{\circ}C$). With prolonged working, there were marked increase in RR were recorded after 30 minutes (the overall increase was $12.4^{\circ}C$). Sweating rate (SR) differed significantly between sexes (p < 0.05), weeks (p < 0.01) and times (p < 0.01) during exercise. Females had a lower mean SR ($225.3g/m^2/h$) than males ($238.8g/m^2/h$). With increasing time, the highest SR was achieved after 30 minutes of exercise of $313.3g/m^2/h$.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.3
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• pp.304-307
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• 1997

Rectal temperature (Tr), skin surface temperatures (Ts), and heart rate (HR) were measured continuously from birth (day 1) till day 7, while resting heat production (HP) was measured in a chamber on days 1, 3, 5 and 7, in order to study the characteristic variation of Tr in newborn calves by heat balance methods. Despite constant levels of milk being given to the newborn calves each day, daily mean resting HP was lowest on the day of birth, then increased to peak on day 3 and then decreased slightly thereafter. Daily mean HR was higher on days 2, 3 and 4, than on other days. Tr exhibited diurnal rhythms and daily mean Tr was low on day 1, high on day 3, and then decreased slightly after day 3. Daily average mean skin temperature (mTs) was similar on all days. Mean body temperature (Tb) exhibited diurnal rhythms and had a similar range between days, suggesting that heat balance and thermoregulation were carried out effectively on each day. The variation of Tb appeared to be synchronized with that of HP and suggested that newborn calves might use variations in the levels of Tb to facilitate the body's required levels of heart loss.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.2
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• pp.163-169
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• 1994

This study was carried on to investigate the effect of physiological significance of hand and foot on thermoregulation and thermal pleasantness in clothed $\mu$ Oral and skin temperatures after immersing hands and feet in the cold or the warm water at Ta of 25 and $20^{\circ}C$, respectively, were compared with four types of garment worn by two healthy male subjects. Four types of gannent expressed as A, B, C, D, were determined by the exposed areas of extremities : hands only are exposed in A, feet only are exposed in B, both hands and forearms are exposed in C, and both feet and legs are exposed in D. Major findings observed reveals that oral temperatures in D were generally maintained higher than those in A, B, and C. This is probably because the size of exposed areas rather than skin temperatures seem to determine the level of core temperature. Also, obtained result that thermal sensations felt by the subjects in foot are more closely related to local skin temperatures when they are compared to those in hand. From these findings it would be suggested that the significance of hand and foot in temperature regulation appears to be connected more with behavioral than with physiological.