Effects of active drinking practices on fluid consumption and sweat rate while exercising in a hot environment

( Youn Sun Son ),( Bong Yeon Hwang ),( Dae Taek Lee ),( Yoon Jung Bae ) 한국운동영양학회 2014 Physical Activity and Nutrition (Phys Act Nutr) Vol.18 No.2

Youn Sun Son, Bong Yeon Hwang, Dae Taek Lee and Yoon Jung Bae. Effects of active drinking practices on fluid consumptionand sweat rate while exercising in a hot environment. JENB., Vol. 18, No. 2, pp.215-223, 2014 [Purpose]To examine the effectsof active drinking practices on fluid consumption and sweat rate while exercising in a hot environment. [Methods]Nine mencompleted two experiments. Each consisted of 3 phases: pre-testing (pre), training period, and post-testing (post). During testing,the subjects ran on a treadmill at a moderate intensity for 90 min at 39 ± 1℃ followed by a 3-h recovery. They drank ad libitum. During training, they ran for 90 min for 7 days while either drinking actively (AH, 150% of weight loss) or passively (PH,50% of weight loss). [Results]The actual volume consumed in training was three times greater during AH than during PH. Inpost during AH, the volume of drinking was two times greater than pre (1592 ± 953 and 855 ± 551 mL, respectively; p < 0.05). No difference in volume consumption during PH between pre and post was found. The sweat loss during exercise was greaterin post (1377 ± 956 mL) than in pre (558 ± 642 mL) during AH (p < 0.05), but not during PH. Rectal temperature and heartrate decreased after training. Serum osmolality following exercise were not different than the baseline or between the conditions. [Conclusion]Active drinking practices while exercising in a hot environment induced greater voluntary fluid intake and sweatloss. [Keyword]voluntary intake, rehydration, thermoregulation.

Body melanization and its adaptive role in thermoregulation and tolerance against desiccating conditions in drosophilids

Subhash RAJPUROHIT,Ravi PARKASH,Seema RAMNIWAS 한국곤충학회 2008 Entomological Research Vol.38 No.1

Melanism seems to have evolved independently through diverse mechanisms in various taxa and different ecological factors could be responsible for selective responses. Increased body melanization at higher altitudes as well as latitudes is generally considered to be adaptive for thermoregulation. Physiological traits such as body melanization and desiccation resistance have been investigated independently in diverse insect taxa at three levels: within populations, between populations and among species. A substantial number of Drosophila studies have reported clinal variations in both these traits along latitude. A possible link between these traits had remained unexplored in wild and laboratory populations of ectothermic insect taxa, including drosophilids, to date. Simultaneous analysis of these traits in assorted darker and lighter phenotypes in each population in the present study showed parallel changes for body melanization and desiccation resistance. The mechanistic basis of evolving desiccation resistance was explained on the basis of differential rates of water loss per hour in darker versus lighter phenotypes in six populations of Drosophila melanogaster from adjacent localities differing substantially in altitude all along the Indian subcontinent. Data on cuticular impermeability suggest a possible role of melanization in desiccation tolerance. However, substantial gaps remain in extending these results to other insect taxa and further exploring the physiological and molecular changes involved in melanization for conferring desiccation resistance.

Pedestrian detection at night time in FIR domain: Comprehensive study about temperature and brightness and new benchmark

Kim, Taehwan,Kim, Sungho Elsevier 2018 Pattern recognition Vol.79 No.-

<P><B>Abstract</B></P> <P>This paper presents a novel method to detect pedestrians in the far infrared (FIR) domain at night. In existing infrared data, the brightness is distorted by the contrast of the scene, causing the performance to degrade. The radiometric temperature was introduced to cope with this issue. The temperature was unaffected by the contrast and was more stable than the brightness because of the limitation to the specific thermal range with thermoregulation. The dataset was constructed across each season and four versions of thermal infrared radiometry aggregated channel feature (TIR-ACF) are presented with normalization using the maximum temperature of humans. In these experiments, the proposed method outperformed the brightness-based baseline method by a maximum 11% on the log-averaged miss rate for seasonal variations. As a result, the physical temperature enhanced the performance and helped detect pedestrians that cannot be found using the brightness with a reduction of false positives.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The seasonal temperature-based pedestrian detection database was constructed. </LI> <LI> The seasonal brightness and temperature of the pedestrians at night were analyzed. </LI> <LI> The proposed temperature-based method outperforms the brightness-based baseline. </LI> <LI> The normalized physical temperature enhances the pedestrian detection performance. </LI> </UL> </P>

하고초추출물의 갑상선기능항진증 랫트모델에서의 한열조절작용에 의한 개선효능 연구

강안나 ( An Na Kang ),강석용 ( Seok Yong Kang ),맹상용 ( Xianglong Meng ),마준남 ( Junnan Ma ),박종훈 ( Jong Hun Park ),박용기 ( Yong-ki Park ) 대한본초학회 2018 大韓本草學會誌 Vol.33 No.4

Objective : This study was intended to examine the effects of water extract of Prunellae Spica (PS), which is a herb with 'cold' nature based on hot and cold theory of traditional Korean medicine. Methods : Hyperthyroidism was induced in SD rats by LT4 (0.5 ㎎/㎏, i.p.) daily for four weeks. After 2 weeks of LT4 injection, rats were divided randomly into four groups; normal, LT4-induced hyperthyroid control, PS extract (500 ㎎/㎏, p.o.)-treated group, and propylthiouracil (PTU, 10 ㎎/㎏, s.c.)-treated positive group. After 2 weeks of drug treatment, all rats were sacrificed and harvested blood samples and thyroid tissues. The changes of body weight, food and water intake, and body temperature were measured weekly. Serological markers were analyzed in sera using an enzyme-based assay, and thyroid tissues were stained with Hematoxylin & Eosin (H&E). Brain and dorsal root ganglion (DRG) tissues were isolated and analyzed the expression of transient receptor potential (TRP) channels by Western blot. Results : PS extract administration attenuated the loss of body weight and the increase of body temperature in LT4- induced hyperthyroidism rats. PS extract increased the level of thyroid stimulating hormone (TSH) and decreased tiiodothyronine (T3) and tetraiodothyronine (T4). In action mechanism, PS extract regulated the expression of transient receptor potential channel subfamily V member 1 (TRPV1) and transient Receptor Potential channel subfamily M member 8 (TRPM8), the thermoregulators. Conclusion : To conclude, PS extract can improve the symptoms of hyperthyroidism through regulation of the thyroid hormones imbalance and thermoregulation via TRP channels.

Pineal-adrenal Relationship: Modulating Effects of Glucocorticoids on Pineal Function to Ameliorate Thermal-stress in Goats

Sejian, V.,Srivastava, R.S.,Varshney, V.P. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.7

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.

고출력 전자기파 노출 환경에서 인체 두부의 온도 변화

김우태(Woo-Tae Kim),육종관(Jong-Gwan Yook) 한국전자파학회 2010 한국전자파학회논문지 Vol.21 No.10

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 ㎒와 1,800 ㎒를 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 ℃ 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 ℃, 피부: 10 ℃)을 야기할 수 있는 전자기파 노출 환경을 예측하기 위해서는 온도 조절 기능을 포함한 해석을 수행해야 한다. 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.

Post-translational regulation of short vegetative phase as a major mechanism for thermoregulation of flowering.

Hwan Lee, Jeong,Sook Chung, Kyung,Kim, Soon-Kap,Ahn, Ji Hoon Landes Bioscience 2014 Plant signaling & behavior Vol.9 No.3

<P>In contrast to our extensive knowledge of vernalization, we know relatively little about the regulation of ambient temperature-responsive flowering. Recent reports revealed that flowering locus M (FLM) and short vegetative phase (SVP) regulate high ambient temperature-responsive flowering through two different mechanisms: degradation of SVP protein and formation of a non-functional SVP-FLM-δ complex. To investigate further the mechanism of thermoregulation of flowering, we performed real-time quantitative polymerase chain reaction (RT-qPCR) and in vitro pull-down assays. We found that FLM-β and FLM-δ transcripts show similar absolute levels at different temperatures. Also, His-SVP protein bound to the GST-FLM-β or -δ proteins with similar binding intensities. These results suggest that functional SVP-FLM-β and non-functional SVP-FLM-δ complexes form similarly at warmer temperatures, thus indicating that post-translational regulation of SVP functions as a major mechanism for thermoregulation in flowering.</P>

Comparison of thermoregulation and physiological responses after swimming exercise according to age and swim cap material in women

신재윤,신윤아,황시영,유경헌 한국체육학회 2019 International journal of human movement science Vol.13 No.3

This study aimedto examine factors that affect body temperature changes and physiological responses during continuous swimming according to swim capmaterial. Subjects included 24 women in their 20s and 40s without any relevant medical histories. The distance of the swim exercise was set to 1500m,and was completed at a pace of 40 s per 50m using the freestyle stroke. Body temperature, skin temperature, heart rate, lactate, rated perceived exertion (RPE), and thermal sensation were measured 30 min before exercise, every 10 min during exercise, immediately after 30 min of exercise, and 30 min after recovery. Body temperature demonstrateda significant interaction effect according to swim cap material and age according to swim time (p<.05). Skin temperature demonstrated a significant difference according to swim time (p<.05). Heart rate was significantly different according to swim exercise (p<.001). Lactic acid demonstrateda significant difference according to swim time (p<.001) and interaction effect (p<.01). RPE demonstrated a significant difference according to swim time (p<.001), and swim time according to age (p<.01) and interaction effects (p<.05). Finally, thermal sensation demonstrateda significant difference over time (p<.001). In conclusion, wearing swim capsmade from a light mesh material was excellent for heat dissipation and breathability, and reduced fatigue and improved exercise performance through temperature control.

Comparison of thermoregulation and physiological responses after swimming exercise according to age and swim cap material in women

( Jae Joon Shin ),( Si Young Hwang ),( Gyeong Heon You ),( Yun A Shin ) 한국체육학회 2019 International journal of human movement science Vol.13 No.3

This study aimed to determine the factors that affect body temperature changes and physiological responses during continuous swimming according to swim cap material. Subjects included 24 women in their 20s and 40s without any relevant medical histories. The distance of the swim exercise was set at 1500m, and was completed at a pace of 40seconds per 50m using the freestyle stroke. Body temperature, skin temperature, heart rate, lactate, rated perceived exertion (RPE), and thermal sensation were measured 30 min before exercise, every 10 min during exercise, immediately after 30 min of exercise, and 30 min after recovery. Body temperature demonstrated a significant interaction effect according to swim cap material and age based on swim time (p<0.05). Skin temperature demonstrated a significant difference according to swim time (p<0.05). Heart rate was significantly different according to swim exercise (p<0.001). Lactic acid demonstrated a significant difference according to swim time (p<0.001) and interaction effect (p<0.01). RPE demonstrated a significant difference according to swim time (p<0.001), and swim time according to age (p<0.01) and interaction effects (p<0.05). Finally, thermal sensation demonstrated a significant difference over time (p<0.001). In conclusion, wearing swim caps made from a light mesh material was excellent for heat dissipation and breathability, and reduced fatigue and improved exercise performance through temperature control.

실내조도가 의복과 환경온 선택에 미치는 영향

정운선(Woon-Seon Jeong) 한국생활환경학회 2003 한국생활환경학회지 Vol.10 No.1

Self-selection behavior of clothing and ambient air temperature were observed to study the behavioral thermoregulation under different light intensity. Eight healthy college-aged women volunteered to participate as the subjects. They were exposed to 26℃ in 400 lx for 20 min (‘Equilibrium’) followed by exposure of 18℃ in 800 lx or 30 lx for 30 min (‘Exposure’). After ‘Exposure’, they were allowed to select air temperature in Experiment 1 and clothing in Experiment 2 in order to decide the comfortable air temperature (CAT) and the comfortable clothing (CC) for their thermal comfort. CAT was higher in 30 lx than in 800 lx (p = 0.016) while CC was not significantly different between 30 lx and 800 lx. Results were discussed and concluded in terms of the thermal comfort and the saving of energy.