• 한국전자파학회논문지
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• 제21권10호
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• pp.1073-1084
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• 2010

본 논문에서는 지속적인 고출력 전자기파 근접 노출 환경에서 인체 두부에서의 온도 변화를 살펴보았다. 근접 전자기파 발생 장치로 반파장 다이폴 안테나를 사용하고, 안테나의 위치는 귀 옆과 눈 앞 두 종류의 환경을 설정하였다. 이때, 안테나의 주파수는 두 종류의 단일 주파수 835 MHz와 1,800 MHz를 고려하였다. 전자기파 노출에 의한 인체의 전자파 흡수율(Specific Absorption Rate: SAR) 값은 시간 영역 유한 차분법(Finite-Difference Time-Domain: FDTD)으로 계산하였고, 인체에서의 온도 변화는 생체 열 방정식(Bio-Heat Equation: BHE)를 이용해 계산하였다. 또한, 연속적인 고출력 노출 환경에서 인체의 온도 변화를 보다 정확히 예측하기 위해서 온도조절 기능(thermoregulation)을 고려하였다. 온도 조절 기능을 고려하지 않을 경우에는 최대 온도 상승은 안테나 출력에 비례하는 것을 확인하였다. 반면에, 온도 조절 기능을 고려하면, 피부의 온도가 $5^{\circ}C$ 이상 증가한 구간에서는 안테나 출력에 비례하는 특성이 나타나지 않는 것을 확인할 수 있었다. 따라서, 수치 해석 방법으로, 인체조직에 손상을 일으키는 온도 상승(뇌: $3.5^{\circ}C$, 피부: $10^{\circ}C$)을 야기할 수 있는 전자기파 노출 환경을 예측하기 위해서는 온도 조절 기능을 포함한 해석을 수행해야 한다.

• 한국의류학회지
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• 제23권7호
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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.

• 대한가정학회지
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• 제39권5호
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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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• 제65권4호
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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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• 제21권7호
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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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• 제62권2호
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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.

• 한국주거학회:학술대회논문집
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• 한국주거학회 1994년도 학술발표대회논문집 하
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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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• 제10권2호
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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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• 제10권3호
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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.

• 한국의류학회지
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• 제18권2호
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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.