Journal articles: 'Thermoregulation of the human body'

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Wang, Lijuan, Yudong Wang, Guohua Tian, and Yuhui Di. "Human transient response under local thermal stimulation." Thermal Science 21, suppl. 1 (2017): 19–24. http://dx.doi.org/10.2298/tsci17s1019w.

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Human body can operate physiological thermoregulation system when it is exposed to cold or hot environment. Whether it can do the same work when a local part of body is stimulated by different temperatures? The objective of this paper is to prove it. Twelve subjects are recruited to participate in this experiment. After stabilizing in a comfort environment, their palms are stimulated by a pouch of 39, 36, 33, 30, and 27?C. Subject?s skin temperature, heart rate, heat flux of skin, and thermal sensation are recorded. The results indicate that when local part is suffering from harsh temperature, the whole body is doing physiological thermoregulation. Besides, when the local part is stimulated by high temperature and its thermal sensation is warm, the thermal sensation of whole body can be neutral. What is more, human body is more sensitive to cool stimulation than to warm one. The conclusions are significant to reveal and make full use of physiological thermoregulation.

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Bobrova, V. I., S. M. Nikiforov, and L. A. Shevchenko. "Thermoregulation of the human body: norm and pathology." Ukrainian Neurological Journal, no. 3—4 (December 15, 2018): 17–25. http://dx.doi.org/10.30978/unj2018-3-17.

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Yang, Kai, Mingli Jiao, Sifan Wang, Yuanyuan Yu, Quan Diao, and Jian Cao. "Thermoregulation properties of composite phase change materials in high temperature environmental conditions." International Journal of Clothing Science and Technology 30, no. 4 (August 6, 2018): 507–16. http://dx.doi.org/10.1108/ijcst-11-2017-0173.

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Purpose The purpose of this paper is to investigate thermoregulation properties of different composite phase change materials (PCMs), which could be used in the high temperature environmental conditions to protect human body against the extra heat flow. Design/methodology/approach Three kinds of composite PCM samples were prepared using the selected pure PCMs, including n-hexadecane, n-octadecane and n-eicosane. The DSC experiment was performed to get the samples’ phase change temperature range and enthalpy. The simulated high temperature experiments were performed using human arms in three different high temperature conditions (40°C, 45°C, 50°C), and the skin temperature variation curves varying with time were obtained. Then a comprehensive index TGP was introduced from the curves and calculated to evaluate the thermoregulation properties of different composite PCM samples comprehensively. Findings Results show that the composite PCM samples could provide much help to the high temperature human body. It could decrease the skin temperature quickly in a short time and it will not cause the over-cooling phenomenon. Comparing with other two composite PCM samples, the thermoregulation properties of the n-hexadecane and n-eicosane composite PCM is the best. Originality/value Using the n-hexadecane and n-eicosane composite PCM may provide people with better protection against the high temperature conditions, which is significative for the manufacture of functional thermoregulating textiles, garments or equipments.

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Acharya, Saraswati, D. B. Gurung, and V. P. Saxena. "Human males and females body thermoregulation: Perfusion effect analysis." Journal of Thermal Biology 45 (October 2014): 30–36. http://dx.doi.org/10.1016/j.jtherbio.2014.07.006.

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Ibraimov, A. I., and S. K. Tabaldiev. "Condensed Chromatin, Cell Thermoregulation and Human Body Heat Conductivity." Journal of Human Ecology 21, no. 1 (January 2007): 1–22. http://dx.doi.org/10.1080/09709274.2007.11905944.

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Masood, Rashid, Hafsa Jamshaid, and Muhammad Anam Khubaib. "Development of knitted vest fabrics for human body thermoregulation." Journal of Thermal Analysis and Calorimetry 139, no. 1 (June 12, 2019): 159–67. http://dx.doi.org/10.1007/s10973-019-08430-2.

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NG, E. Y. K., and L. W. LIM. "STUDY OF HUMAN THERMOREGULATION: ADAPTIVE OPTIMIZATION CONTROL THEORY ANALYSIS." Journal of Mechanics in Medicine and Biology 08, no. 01 (March 2008): 97–108. http://dx.doi.org/10.1142/s021951940800253x.

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An example of homeostasis is temperature regulation at a desired level; this physiological process leads to the preservation of a stable biological environment. A control-theory–based model permits a biomedical engineer to understand the complex operation of thermoregulation, by converting general information to knowledge, and can be integrated to see how systemic parameters influence the entire system. The thermal inputs organized in the hypothalamus to activate thermoregulation responses to heat and cold stimuli, with the widely accepted set-point hypothesis for the regulation of body temperature from a control systems point of view, are, however, not entirely known. There are circumstances (e.g. fever) in which the presumed set-point mechanism appears to break down. This paper evaluates a novel set-level adaptive optimal thermal control paradigm inspired by Hebbian covariance synaptic adaptation, previously proposed based on its potential to predict the homeostatic respiratory system. It introduces a Hebbian feedback covariance learning (HFCL) concept in order to align a neuronal network into the analysis of the thermoregulation system. Hebbian theory is concerned with how neurons connect among themselves to become engrams. The passive-active mathematical model for simulating human thermoregulation during exercise was compared in cool, warm, and hot environments, and then was translated into MATLAB to predict thermoregulation. The two-node core and shell model predictions are comparable with observed thermoregulation responses from the existing literature. The thermoregulation changes with respect to proportionality constant and sensitivity of the receptors. A reasonably general agreement with the measured mean group data of earlier performed laboratory exercise studies was obtained for peak temperature, although it tended to overpredict the core body temperature.

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Tansey, Etain A., and Christopher D. Johnson. "Recent advances in thermoregulation." Advances in Physiology Education 39, no. 3 (September 2015): 139–48. http://dx.doi.org/10.1152/advan.00126.2014.

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Thermoregulation is the maintenance of a relatively constant core body temperature. Humans normally maintain a body temperature at 37°C, and maintenance of this relatively high temperature is critical to human survival. This concept is so important that control of thermoregulation is often the principal example cited when teaching physiological homeostasis. A basic understanding of the processes underpinning temperature regulation is necessary for all undergraduate students studying biology and biology-related disciplines, and a thorough understanding is necessary for those students in clinical training. Our aim in this review is to broadly present the thermoregulatory process taking into account current advances in this area. First, we summarize the basic concepts of thermoregulation and subsequently assess the physiological responses to heat and cold stress, including vasodilation and vasoconstriction, sweating, nonshivering thermogenesis, piloerection, shivering, and altered behavior. Current research is presented concerning the body's detection of thermal challenge, peripheral and central thermoregulatory control mechanisms, including brown adipose tissue in adult humans and temperature transduction by the relatively recently discovered transient receptor potential channels. Finally, we present an updated understanding of the neuroanatomic circuitry supporting thermoregulation.

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YOSHIDA, Shinji. "Relationship Between Wind Environment and Thermoregulation of a Human Body." Wind Engineers, JAWE 45, no. 3 (2020): 206–13. http://dx.doi.org/10.5359/jawe.45.206.

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Kumari, Babita, and Neeru Adlakha. "Two-dimensional finite difference model to study temperature distribution in SST regions of human limbs immediately after physical exercise in cold climate." International Journal of Computational Materials Science and Engineering 04, no. 01 (March 2015): 1550002. http://dx.doi.org/10.1142/s2047684115500025.

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Thermoregulation is a complex mechanism regulating heat production within the body (chemical thermoregulation) and heat exchange between the body and the environment (physical thermoregulation) in such a way that the heat exchange is balanced and deep body temperatures are relatively stable. The external heat transfer mechanisms are radiation, conduction, convection and evaporation. The physical activity causes thermal stress and poses challenges for this thermoregulation. In this paper, a model has been developed to study temperature distribution in SST regions of human limbs immediately after physical exercise under cold climate. It is assumed that the subject is doing exercise initially and comes to rest at time t = 0. The human limb is assumed to be of cylindrical shape. The peripheral region of limb is divided into three natural components namely epidermis, dermis and subdermal tissues (SST). Appropriate boundary conditions have been framed based on the physical conditions of the problem. Finite difference has been employed for time, radial and angular variables. The numerical results have been used to obtain temperature profiles in the SST region immediately after continuous exercise for a two-dimensional unsteady state case. The results have been used to analyze the thermal stress in relation to light, moderate and vigorous intensity exercise.

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Yang, Yu, Runming Yao, Baizhan Li, Hong Liu, and Lai Jiang. "A method of evaluating the accuracy of human body thermoregulation models." Building and Environment 87 (May 2015): 1–9. http://dx.doi.org/10.1016/j.buildenv.2015.01.013.

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Li, Baizhan, Yu Yang, Runming Yao, Hong Liu, and Yongqiang Li. "A simplified thermoregulation model of the human body in warm conditions." Applied Ergonomics 59 (March 2017): 387–400. http://dx.doi.org/10.1016/j.apergo.2016.09.010.

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Gaifutdinov, R. T., М. F. Ismagilov, and D. R. Khasanova. "Physiological mechanisms of thermoregulation, their disorders in cerebral autonomic dysregulation." Neurology Bulletin XXXI, no. 1-4 (September 15, 1999): 63–76. http://dx.doi.org/10.17816/nb80949.

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Body temperature reflects the state of homeostasis, the intensity of bioenergetic processes and the thermal state of the human body as a whole. In the physical sense, body temperature is a measure of the amount of thermal energy in the body, determines the rate of chemical reactions, affecting all biological functions of the body.

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Acharya, Saraswati, D. B. Gurung, and V. P. Saxena. "Effect of Metabolic Reactions on Thermoregulation in Human Males and Females Body." Applied Mathematics 04, no. 05 (2013): 39–48. http://dx.doi.org/10.4236/am.2013.45a005.

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Shrestha, Dev Chandra, and Saraswati Acharya. "Time Dependent Mathematical Model of Thermoregulation in Human Dermal Parts During Sarcopenia." Journal of Nepal Mathematical Society 4, no. 1 (May 14, 2021): 41–53. http://dx.doi.org/10.3126/jnms.v4i1.37112.

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Sarcopenia is an illness characterized by the loss of skeletal muscle mass, and its strength occurs in aging after 50 years. Muscle mass plays a vital role in body weight and metabolism. The loses in body weight impact reducing the basal metabolic rate (BMR). The BMR affects the human body temperature due to lower metabolic heat production during sarcopenia. The present study deals with time dependent temperature variation in human dermal parts during sarcopenia. The finite element method is used to solve a one-dimensional bioheat equation. In this model, the thickness of the epidermis, dermis layers, and the BMR of different aging, are estimated. The results show the nodal temperature of the epidermis and dermis layers increases due to reducing the thickness. Further, the subcutaneous nodal temperature slightly decreases due to the cause of BMR.

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Smalko, Zbigniew. "An Impact of Thermodynamic Processes in Human Bodies on Performance Reliability of Individuals." Journal of KONBiN 27, no. 1 (January 29, 2015): 5–22. http://dx.doi.org/10.2478/jok-2013-0101.

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Abstract The article presents the problem of the influence of thermodynamic factors on human fallibility in different zones of thermal discomfort. Describes the processes of energy in the human body. Been given a formal description of the energy balance of the human body thermoregulation. Pointed to human reactions to temperature changes of internal and external environment, including reactions associated with exercise. The methodology to estimate and determine the reliability of indicators of human basal acting in different zones of thermal discomfort. The significant effect of thermodynamic factors on the reliability and security ofperson.

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Gao, Naiping, Jianlei Niu, and Hui Zhang. "Coupling CFD and Human Body Thermoregulation Model for the Assessment of Personalized Ventilation." HVAC&R Research 12, no. 3 (July 1, 2006): 497–518. http://dx.doi.org/10.1080/10789669.2006.10391191.

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Angelova, Radostina A. "Numerical simulation of the thermoregulation of clothed human body: skin and clothing temperatures." Journal of the Brazilian Society of Mechanical Sciences and Engineering 37, no. 1 (May 24, 2014): 297–303. http://dx.doi.org/10.1007/s40430-014-0189-0.

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Kang, Zhanxiao, Faming Wang, and Udayraj. "An advanced three-dimensional thermoregulation model of the human body: Development and validation." International Communications in Heat and Mass Transfer 107 (October 2019): 34–43. http://dx.doi.org/10.1016/j.icheatmasstransfer.2019.05.006.

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Shrestha, Dev Chandra, Saraswati Acharya, and Dil Bahadur Gurung. "A Finite Element Approach to Evaluate Thermoregulation in the Human Body due to the Effects of Sweat Evaporation during Cooking, Cleaning, and Walking." Mathematical Problems in Engineering 2021 (May 26, 2021): 1–14. http://dx.doi.org/10.1155/2021/5539151.

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Sweat evaporation is the principal process of dissipating heat energy in a hot environment and during activities. Sweat loss is significantly affected by the level of energy expenditure, hormones, and the number of sweat glands. The thickness of the skin layer plays a vital role to maintain body temperature. The rate of sweat evaporation varies with ambient temperature and activity level. On increasing both metabolism and ambient temperature, sweat rate loss also increases and controls the body in the thermoregulatory system. The evaporative sweat release rate has a linear behavior. The appropriate physical and physiological parameters that affect thermoregulation have been incorporated into the model. The study presents the temperature distribution in three layers: epidermis, dermis, and subcutaneous tissue (SST) of the human dermal parts during cooking, cleaning, and walking. The solution is obtained by using the finite element method. The results demonstrate that the body mechanism keeps the body in thermoregulation by increasing the sweat evaporation rate exhibited by increasing the ambient temperature and metabolism during strenuous activities.

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Lim, Chin Leong. "Fundamental Concepts of Human Thermoregulation and Adaptation to Heat: A Review in the Context of Global Warming." International Journal of Environmental Research and Public Health 17, no. 21 (October 24, 2020): 7795. http://dx.doi.org/10.3390/ijerph17217795.

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The international community has recognized global warming as an impending catastrophe that poses significant threat to life on earth. In response, the signatories of the Paris Agreement (2015) have committed to limit the increase in global mean temperature to <1.5 °C from pre-industry period, which is defined as 1850–1890. Considering that the protection of human life is a central focus in the Paris Agreement, the naturally endowed properties of the human body to protect itself from environmental extremes should form the core of an integrated and multifaceted solution against global warming. Scholars believe that heat and thermoregulation played important roles in the evolution of life and continue to be a central mechanism that allows humans to explore, labor and live in extreme conditions. However, the international effort against global warming has focused primarily on protecting the environment and on the reduction of greenhouse gases by changing human behavior, industrial practices and government policies, with limited consideration given to the nature and design of the human thermoregulatory system. Global warming is projected to challenge the limits of human thermoregulation, which can be enhanced by complementing innate human thermo-plasticity with the appropriate behavioral changes and technological innovations. Therefore, the primary aim of this review is to discuss the fundamental concepts and physiology of human thermoregulation as the underlying bases for human adaptation to global warming. Potential strategies to extend human tolerance against environmental heat through behavioral adaptations and technological innovations will also be discussed. An important behavioral adaptation postulated by this review is that sleep/wake cycles would gravitate towards a sub-nocturnal pattern, especially for outdoor activities, to avoid the heat in the day. Technologically, the current concept of air conditioning the space in the room would likely steer towards the concept of targeted body surface cooling. The current review was conducted using materials that were derived from PubMed search engine and the personal library of the author. The PubMed search was conducted using combinations of keywords that are related to the theme and topics in the respective sections of the review. The final set of articles selected were considered “state of the art,” based on their contributions to the strength of scientific evidence and novelty in the domain knowledge on human thermoregulation and global warming.

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Prusaczyk, W. K., and M. N. Sawka. "Effects of pyridostigmine bromide on human thermoregulation during cold water immersion." Journal of Applied Physiology 71, no. 2 (August 1, 1991): 432–37. http://dx.doi.org/10.1152/jappl.1991.71.2.432.

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This study examined the effects of an oral 30-mg dose of pyridostigmine bromide (PYR) on thermoregulatory and physiological responses of men undergoing cold stress. Six men were immersed in cold water (20 degrees C) for up to 180 min on two occasions, once each 2 h after ingestion of PYR and 2 h after ingestion of a placebo. With PRY, erythrocyte cholinesterase inhibition was 33 +/- 12% (SD) 110 min postingestion (10 min preimmersion) and 30 +/- 7% at termination of exposure (mean 117 min). Percent cholinesterase inhibition was significantly related to lean body mass (r = -0.91, P less than 0.01). Abdominal discomfort caused termination in three of six PYR experiments but in none of the control experiments (mean exposure time 142 min). During immersion, metabolic rate, ventilatory volume, and respiratory rate increased significantly (P less than 0.05) over preimmersion levels and metabolic rate increased with duration of immersion (P less than 0.01) in both treatment but did not differ between conditions. PYR had no significant effect on rectal temperature, mean body temperature, thermal sensations, heart rate, plasma cortisol, or change in plasma volume. It was concluded that a 30-mg dose of PYR does not increase an individual's susceptibility to hypothermia during cold water immersion; however, in combination with cold stress, PYR may result in marked abdominal cramping and limit cold tolerance.

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Takahashi, Yoshito, Masayuki Oata, Jun-ichi Asaka, Akihisa Nomoto, and Shin-ichi Tanabe. "Coupling of a cardiovascular model with a thermoregulation model to predict human blood pressure under unsteady environmental conditions." E3S Web of Conferences 111 (2019): 02062. http://dx.doi.org/10.1051/e3sconf/201911102062.

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We coupled a cardiovascular model with a thermoregulation model to predict human blood pressure in unsteady environmental conditions. Our cardiovascular model is a lumped parameter model and consists of 42 segments, which include the entire artery and vein system, divided into 18 segments; the heart, divided into 4 segments; and the pulmonary artery and vein. The vessel parameters were adjusted on the basis of local body blood volume and flow of the thermoregulation model in a thermoneutral environment. Blood pressure under unsteady environmental conditions is predicted by changing the heart rate and vessel resistance of the cardiovascular model which is controlled by blood flow that the thermoregulation model predicts. It is possible to predict the increase in blood pressure under cold environmental conditions and the increase in cardiac output under hot environmental conditions and when bathing. The model was validated by simulating bathing experiments. As the result, the model predicted the peak blood pressure later than the experimental data in a cold environment. To improve the accuracy of the model, it is necessary to consider a method for controlling the heart rate, vessel resistance, and gravity effects after a change in posture.

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Khan, Zahid Akhtar, Irfan Anjum Badruddin magami, Suresh Maniyan, and Gulam Abdul Quadir. "A simplified thermal model for a clothed human operator with thermoregulation." IIUM Engineering Journal 8, no. 1 (September 29, 2010): 1–18. http://dx.doi.org/10.31436/iiumej.v8i1.84.

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This paper presents a simplified yet comprehensive mathematical model to predict steady state temperature distribution for various regions of male clothed human operators who are healthy, passive/active and lean/obese under the influence of different environmental conditions using thermoregulatory control concept. The present model is able to predict the core temperature, close to 37oC for a healthy, passive/active and lean/obese operator at normal ambient temperatures. It is observed that due to increase in body fat, BF the skin temperature, of the operator decreases by a small amount. However, effect of age of the operator on is found to be insignificant. The present model has been validated against the experimental data available in the literature.

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Périard, Julien D., Thijs M. H. Eijsvogels, and Hein A. M. Daanen. "Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies." Physiological Reviews 101, no. 4 (October 1, 2021): 1873–979. http://dx.doi.org/10.1152/physrev.00038.2020.

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A rise in body core temperature and loss of body water via sweating are natural consequences of prolonged exercise in the heat. This review provides a comprehensive and integrative overview of how the human body responds to exercise under heat stress and the countermeasures that can be adopted to enhance aerobic performance under such environmental conditions. The fundamental concepts and physiological processes associated with thermoregulation and fluid balance are initially described, followed by a summary of methods to determine thermal strain and hydration status. An outline is provided on how exercise-heat stress disrupts these homeostatic processes, leading to hyperthermia, hypohydration, sodium disturbances, and in some cases exertional heat illness. The impact of heat stress on human performance is also examined, including the underlying physiological mechanisms that mediate the impairment of exercise performance. Similarly, the influence of hydration status on performance in the heat and how systemic and peripheral hemodynamic adjustments contribute to fatigue development is elucidated. This review also discusses strategies to mitigate the effects of hyperthermia and hypohydration on exercise performance in the heat by examining the benefits of heat acclimation, cooling strategies, and hyperhydration. Finally, contemporary controversies are summarized and future research directions are provided.

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Fontana, Piero, Fabio Saiani, Marc Grütter, Jean-Philippe Croset, André Capt, Martin Camenzind, Matthew Morrissey, René M. Rossi, and Simon Annaheim. "Exercise intensity dependent relevance of protective textile properties for human thermo-physiology." Textile Research Journal 87, no. 12 (June 24, 2016): 1425–34. http://dx.doi.org/10.1177/0040517516654105.

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During firefighting, thermoregulation is challenged due to a combination of harsh environmental conditions, high metabolic rates and personal protective clothing (PPC). Consequently, investigations of thermoregulation in firefighters should not only consider climate and exercise intensity, but technical properties of textiles too. Therefore, laboratory textile performance simulations may provide additional insights into textile-dependent thermoregulatory responses to exercise. In order to investigate the thermo-physiological relevance of textile properties and to test how different garments affect thermoregulation at different exercise intensities, we analyzed the results of a standard laboratory test and human subject trials by relating functional properties of textiles to thermo-physiological responses. Ten professional, healthy, male firefighters (age: 43 ± 6 y, weight: 84.3 ± 10.3kg, height: 1.79 ± 0.05m) performed low and moderate intensity exercise wearing garments previously evaluated with a sweating torso system to characterize thermal and evaporative properties. Functional properties of PPC and the control garment differed markedly. Consequently, skin temperature was higher using PPC at both exercise intensities (low: 36.27 ± 0.32 versus 36.75 ± 0.15℃, P < 0.05; moderate: 36.53 ± 0.34 versus 37.18 ± 0.23℃, P < 0.001), while core body temperature was only higher for PPC at moderate (37.54 ± 0.24 versus 37.83 ± 0.27℃, P < 0.05), but not low-intensity exercise (37.26 ± 0.21 versus 37.21 ± 0.19, P = 0.685). Differences in thermal and evaporative properties between textiles are reflected in thermo-physiological responses during human subject trials. However, an appropriate exercise intensity has to be chosen in order to challenge textile performance during exercise tests.

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Teodoreanu, Elena. "Index Bioclimatic "Wind-Chill"." Present Environment and Sustainable Development 9, no. 1 (May 1, 2015): 237–42. http://dx.doi.org/10.1515/pesd-2015-0017.

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Abstract This paper presents an important bioclimatic index which shows the influence of wind on the human body thermoregulation. When the air temperature is high, the wind increases thermal comfort. But more important for the body is the wind when the air temperature is low. When the air temperature is lower and wind speed higher, the human body is threatening to freeze faster. Cold wind index is used in Canada, USA, Russia (temperature "equivalent" to the facial skin) etc., in the weather forecast every day in the cold season. The index can be used and for bioclimatic regionalization, in the form of skin temperature index.

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Xu, Jingxian, Agnes Psikuta, Jun Li, Simon Annaheim, and René M. Rossi. "Evaluation of the convective heat transfer coefficient of human body and its effect on the human thermoregulation predictions." Building and Environment 196 (June 2021): 107778. http://dx.doi.org/10.1016/j.buildenv.2021.107778.

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Gruss, Laura Tobias, and Daniel Schmitt. "The evolution of the human pelvis: changing adaptations to bipedalism, obstetrics and thermoregulation." Philosophical Transactions of the Royal Society B: Biological Sciences 370, no. 1663 (March 5, 2015): 20140063. http://dx.doi.org/10.1098/rstb.2014.0063.

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The fossil record of the human pelvis reveals the selective priorities acting on hominin anatomy at different points in our evolutionary history, during which mechanical requirements for locomotion, childbirth and thermoregulation often conflicted. In our earliest upright ancestors, fundamental alterations of the pelvis compared with non-human primates facilitated bipedal walking. Further changes early in hominin evolution produced a platypelloid birth canal in a pelvis that was wide overall, with flaring ilia. This pelvic form was maintained over 3–4 Myr with only moderate changes in response to greater habitat diversity, changes in locomotor behaviour and increases in brain size. It was not until Homo sapiens evolved in Africa and the Middle East 200 000 years ago that the narrow anatomically modern pelvis with a more circular birth canal emerged. This major change appears to reflect selective pressures for further increases in neonatal brain size and for a narrow body shape associated with heat dissipation in warm environments. The advent of the modern birth canal, the shape and alignment of which require fetal rotation during birth, allowed the earliest members of our species to deal obstetrically with increases in encephalization while maintaining a narrow body to meet thermoregulatory demands and enhance locomotor performance.

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Hariharakrishnan, Jayaram, and Bhalaji N. "Adaptability Analysis of 6LoWPAN and RPL for Healthcare applications of Internet-of-Things." June 2021 2, no. 2 (May 11, 2021): 69–81. http://dx.doi.org/10.36548/jismac.2021.2.001.

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Ubiquitous Networks powered by Wireless Sensor Networks (WSN) is cutting across many technologies assisting day-to-day human activities. This technology confers the ability to sense and surmise the external environmental factors of various ecologies. Interconnection of these sensing devices for Machine to Machine (M2M) communication leads to the origination of Internet-of-Things (IoT). Recent advancements in the technology of Internet-of-Things guides the production of smart objects that can accomplish location, identification, connection and measurement of external factors. This leads to a new type of communication paradigm between objects and humans. One of the important problem due to the population explosion that can be addressed by IoT is the Healthcare of individual human beings. Remote health monitoring is one of the greatest technology exploited in medical professionals to keep a check on the patient’s important health factors periodically. This was done in a smaller geographical area before the era of IoT. As IoT can communicate to other Internet, This remote healthcare monitoring can now be applied over a wider geographical topology. This paper extensively analyses the performance of 6LoWPAN and RPL IoT for healthcare applications. This paper especially focuses on monitoring an athlete's thermoregulation. Also, a new technique to identify and train marathon athletes to the race topography has been proposed. In this technique, each athlete is fitted with wearable sensors in their body in the training session to monitor and analyze the thermoregulation process occurring during training. After a detailed analysis of the athletes’ thermoregulation process, personal training schedules are charted down according to variation in the thermoregulation process in each athlete. This technique helps to monitor each athlete’s progress personally with less number of coaches and medical professionals leading to the prevention of unexpected death of a healthy athlete.

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Škop, Vojtěch, Naili Liu, Juen Guo, Oksana Gavrilova, and Marc L. Reitman. "The contribution of the mouse tail to thermoregulation is modest." American Journal of Physiology-Endocrinology and Metabolism 319, no. 2 (August 1, 2020): E438—E446. http://dx.doi.org/10.1152/ajpendo.00133.2020.

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Understanding mouse thermal physiology informs the usefulness of mice as models of human disease. It is widely assumed that the mouse tail contributes greatly to heat loss (as it does in rat), but this has not been quantitated. We studied C57BL/6J mice after tail amputation. Tailless mice housed at 22°C did not differ from littermate controls in body weight, lean or fat content, or energy expenditure. With acute changes in ambient temperature from 19 to 39°C, tailless and control mice demonstrated similar body temperatures (Tb), metabolic rates, and heat conductances and no difference in thermoneutral point. Treatment with prazosin, an α1-adrenergic antagonist and vasodilator, increased tail temperature in control mice by up to 4.8 ± 0.8°C. Comparing prazosin treatment in tailless and control mice suggested that the tail’s contribution to total heat loss was a nonsignificant 3.4%. Major heat stress produced by treatment at 30°C with CL316243, a β3-adrenergic agonist, increased metabolic rate and Tb and, at a matched increase in metabolic rate, the tailless mice showed a 0.72 ± 0.14°C greater Tb increase and 7.6% lower whole body heat conductance. Thus, the mouse tail is a useful biomarker of vasodilation and thermoregulation, but in our experiments contributes only 5–8% of whole body heat dissipation, less than the 17% reported for rat. Heat dissipation through the tail is important under extreme scenarios such as pharmacological activation of brown adipose tissue; however, non-tail contributions to heat loss may have been underestimated in the mouse.

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Schlader, Zachary J., Blair D. Johnson, Riana R. Pryor, Jocelyn Stooks, Brian M. Clemency, and David Hostler. "Human thermoregulation during prolonged exposure to warm and extremely humid environments expected to occur in disabled submarine scenarios." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 318, no. 5 (May 1, 2020): R950—R960. http://dx.doi.org/10.1152/ajpregu.00018.2020.

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Military and civilian emergency situations often involve prolonged exposures to warm and very humid environments. We tested the hypothesis that increases in core temperature and body fluid losses during prolonged exposure to warm and very humid environments are dependent on dry bulb temperature. On three occasions, 15 healthy males (23 ± 3 yr) sat in 32.1 ± 0.1°C, 33.1 ± 0.2°C, or 35.0 ± 0.1°C and 95 ± 2% relative humidity normobaric environments for 8 h. Core temperature (telemetry pill) and percent change in body weight, an index of changes in total body water occurring secondary to sweat loss, were measured every hour. Linear regression models were fit to core temperature (over the final 4 h) and percent changes in body weight (over the entire 8 h) for each subject. These equations were used to predict core temperature and percent changes in body weight for up to 24 h. At the end of the 8-h exposure, core temperature was higher in 35°C (38.2 ± 0.4°C, P < 0.01) compared with 32°C (37.2 ± 0.2°C) and 33°C (37.5 ± 0.2°C). At this time, percent changes in body weight were greater in 35°C (−1.9 ± 0.5%) compared with 32°C (−1.4 ± 0.3%, P < 0.01) but not 33°C (−1.6 ± 0.6%, P = 0.17). At 24 h, predicted core temperature was higher in 35°C (39.2 ± 1.4°C, P < 0.01) compared with 32°C (37.6 ± 0.9°C) and 33°C (37.5 ± 0.9°C), and predicted percent changes in body weight were greater in 35°C (−6.1 ± 2.4%) compared with 32°C (−4.6 ± 1.5%, P = 0.04) but not 33°C (−5.3 ± 2.0%, P = 0.43). Prolonged exposure to 35°C, but not 32°C or 33°C, dry bulb temperatures and high humidity is uncompensable heat stress, which exacerbates body fluid losses.

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Queiroz do Amaral, Lia. "Loss of body hair, bipedality and thermoregulation. Comments on recent papers in theJournal of Human Evolution." Journal of Human Evolution 30, no. 4 (April 1996): 357–66. http://dx.doi.org/10.1006/jhev.1996.0029.

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Fiala, Dusan, Kevin J. Lomas, and Martin Stohrer. "A computer model of human thermoregulation for a wide range of environmental conditions: the passive system." Journal of Applied Physiology 87, no. 5 (November 1, 1999): 1957–72. http://dx.doi.org/10.1152/jappl.1999.87.5.1957.

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A dynamic model predicting human thermal responses in cold, cool, neutral, warm, and hot environments is presented in a two-part study. This, the first paper, is concerned with aspects of the passive system: 1) modeling the human body, 2) modeling heat-transport mechanisms within the body and at its periphery, and 3) the numerical procedure. A paper in preparation will describe the active system and compare the model predictions with experimental data and the predictions by other models. Here, emphasis is given to a detailed modeling of the heat exchange with the environment: local variations of surface convection, directional radiation exchange, evaporation and moisture collection at the skin, and the nonuniformity of clothing ensembles. Other thermal effects are also modeled: the impact of activity level on work efficacy and the change of the effective radiant body area with posture. A stable and accurate hybrid numerical scheme was used to solve the set of differential equations. Predictions of the passive system model are compared with available analytic solutions for cylinders and spheres and show good agreement and stable numerical behavior even for large time steps.

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Havenith, George. "Individualized model of human thermoregulation for the simulation of heat stress response." Journal of Applied Physiology 90, no. 5 (May 1, 2001): 1943–54. http://dx.doi.org/10.1152/jappl.2001.90.5.1943.

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A population-based dynamic model of human thermoregulation was expanded with control equations incorporating the individual person's characteristics (body surface area, mass, fat%, maximal O2 uptake, acclimation). These affect both the passive (heat capacity, insulation) and active systems (sweating and skin blood flow function). Model parameters were estimated from literature data. Other data, collected for the study of individual differences {working at relative or absolute workloads in hot-dry [45°C, 20% relative humidity (rh)], warm-humid [35°C, 80% rh], and cool [21°C, 50% rh] environments}, were used for validation. The individualized model provides an improved prediction [mean core temperature error, −0.21 → −0.07°C ( P< 0.001); mean squared error, 0.40 → 0.16°C, ( P < 0.001)]. The magnitude of improvement varies substantially with the climate and work type. Relative to an empirical multiple-regression model derived from these specific data sets, the analytical simulation model has between 54 and 89% of its predictive power, except for the cool climate, in which this ratio is zero. In conclusion, individualization of the model allows improved prediction of heat strain, although a substantial error remains.

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Holtzclaw, Barbara J. "Circadian Rhythmicity and Homeostatic Stability in Thermoregulation." Biological Research For Nursing 2, no. 4 (April 2001): 221–35. http://dx.doi.org/10.1177/109980040100200402.

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Stability and circadian variation in core body temperature (Tc) were believed to be homeostatic responses until well into the 20th century. Defense of a narrow thermoneutral range was well documented, whereas circadian oscillations were attributed to episodic biochemical and environmental stimuli or chronological stressors in life routines. Research in thermal physiology has illuminated several of the “black boxes” in the understanding of temperature regulation, and advances in chronobiology have shattered old paradigms. While these discoveries are still evolving, existing information provides valuable clues about physiological responses to heat loss or overheating that could improve clinical assessment and intervention. Discoveries that circadian rhythm of Tc is regulated by an endogenous “clock” and is remarkably stable have helped to make it the most widely used circadian indicator. More recently, Tc was found to exert its own cyclic rhythm under free-running conditions. While some investigators claim that circadian and homeostatic processes are independent, there are conditions in which clinical distinctions are less clear. This overview reviews contemporary scientific findings about circadian and homeostatic processes in thermoregulation. Examples are drawn from human and animal research. Physiological responses and mechanisms are explained in relation to their relevance to clinical treatment or health care. Gaps in existing research and application are discussed.

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Koscheyev, Victor S. "Physiological Considerations in the Design of Clothing and Protective Equipment for Extreme Environments and in Modeling Human Heat Exchange." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 44, no. 12 (July 2000): 2–796. http://dx.doi.org/10.1177/154193120004401298.

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A new era is commencing in which the design of clothing and protective equipment is increasingly taking into account physiological data about human functioning in extreme environments. In these conditions, there is an intensive influence of environmental factors on body systems. Physiological in combination with other types of countermeasures that provide comfort are necessary for stabilizing homeostasis. This approach is extremely important for the design of heavy protective equipment that is widely used in such conditions as space, harsh terrestrial environments, undersea, and in military situations. A physiological overview of the human body for design and modeling purposes is presented, relying on extensive research findings on human thermoregulation and heat exchange using an experimental water circulating plastic tubing garment with the capacity for simultaneous cooling/warming of different body areas. The fingers have great potential as an informative site for providing accurate information about actual body heat status, developing an automatic feedback system between body heat content and the reactivity of the cooling/warming system, and improving modeling approaches.

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KUMARI, BABITA, and NEERU ADLAKHA. "TWO-DIMENSIONAL FINITE ELEMENT MODEL TO STUDY THERMO BIOMECHANICS IN PERIPHERAL REGIONS OF HUMAN LIMBS DUE TO EXERCISE IN COLD CLIMATE." Journal of Mechanics in Medicine and Biology 17, no. 01 (February 2017): 1750002. http://dx.doi.org/10.1142/s0219519417500026.

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Human beings are equipped with thermo sensitivity, thermoregulation and thermo protection for maintaining the structure and function of their body organs. The thermoregulatory responses and disturbances caused by physical activity in thermo biomechanics of human body organs are not well understood. The mechanism of thermoregulation exhibits a beautiful coordination of biophysical process in order to balance distribution caused by a biothermal system due to physical exercise and other abnormal conditions. In view of above, a model has been developed to study the thermal dynamics in peripheral region of human limbs immediately after exercise under cold climatic conditions. The human limb is assumed to be of cylindrical shape. The peripheral region of limb is divided into three natural components namely epidermis, dermis and subdermal tissues. Appropriate boundary conditions have been framed based on the physical condition of the problem. Finite difference has been employed for time variable and the finite element method is employed along radial and angular direction. The numerical results have been used to obtain temperature profiles in the peripheral region immediately after continuous exercise for a two-dimensional unsteady state case. These results have been used to analyze the thermal disturbances caused by the different intensities of physical exercise in the peripheral region of human limbs. Such a model can be developed to study the generated thermal information which can be useful to biomedical science to analyze the impact of thermal stress on mechanism of thermoregulation causing thermal injuries like heat cramps, heat exhaustion and heat stroke. The results give the idea about the capacity of biothermo mechanisms of human limbs in counting balance. The thermal stress is caused by different intensities of physical exercise. These results can be useful for the biomedical scientists to understand the thermal discomfort caused by different intensities of physical exercise and the time period of rest required to overcome discomfort. Further, the result can be useful to biomedical scientists for developing protocols for physical exercise and rest required by the subject for different intensities of physical exercise and prevent thermal injuries in the workers and sportsmen.

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Nomoto, Akihisa, Yoshito Takahashi, Yoshiichi Ozeki, Masayuki Ogata, and Shin-ichi Tanabe. "Prediction of physiological exertion in hot environments using the JOS-2 thermoregulation model." E3S Web of Conferences 111 (2019): 02058. http://dx.doi.org/10.1051/e3sconf/201911102058.

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In recent years, the outdoor summer environment in Japan has become progressively warmer due to the severity of the heat island phenomenon. The danger of heat stroke and thermal comfort outdoors in summer are regarded as problems. In order to evaluate these problems, it is important to evaluate physiological exertion in the human body. The purpose of this research is to demonstrate the possibility of predicting physiological exertion in the human body with high accuracy in an outdoor environment during summer using the JOS-2 thermoregulation model developed by our research group. First, the Japanese metabolic rate in summer and autumn was measured for various activities, including sitting, standing, and walking. As a result, we found that the metabolic rate during sitting and standing was lower by about 10% in summer than in autumn. Next, using the obtained metabolic rate measurement as an input to the model, the experiment in an outdoor environment during summer was reproduced using JOS-2. The accuracy of the predicted mean skin temperature and local skin wettedness in an outdoor environment during summer was improved by choosing the appropriate input to the model.

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Shabat, Yael Ben, Avraham Shitzer, and Dusan Fiala. "Modified wind chill temperatures determined by a whole body thermoregulation model and human-based facial convective coefficients." International Journal of Biometeorology 58, no. 6 (June 28, 2013): 1007–15. http://dx.doi.org/10.1007/s00484-013-0698-z.

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Gruntkoskyi, M. S., V. M. Kondtratiuk, S. M. Gryshchenko, N. P. Hryshchenko, and I. S. Mytyay. "Influence of Nanovulin-VRKh on cattle thermoregulation and chemical composition of milk." Ukrainian Journal of Ecology 10, no. 1 (February 15, 2020): 139–44. http://dx.doi.org/10.15421/2020_22.

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The current research described the effect of neurotropic and metabolic non-hormonal biologically active medicine Nanovulin-VRKh © on the milk yield amount and the milk quality. Two cow groups were under study: the experimental and the control groups, each including four cows. The results showed that two of the neurotropic and metabolic Nanovulin-VRKh injections made 12 and 24 hours after the insemination did not effect the body thermoregulation of cows. Administration of the Nanovulin-VRKh contributes to stable fat formation in cow milk. Increased content of protein, nonfat milk solids, stable fat formation in milk were due to Nanovulin-VRKh administration. It was also established that, in the milk of experimental animals were administered the Nanovulin-VRKh, the pronounced effect of the drug on the protein, fat and nonfat milk solids content was observed, and the prolonged effect on these indices was reported during the fourth milking. Introduction of Cuprum aqua-chelate into the drug did not has toxic effect on the animal body and therefore would not effect the human health through the dairy products.

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Joyner, Michael J., Jacqueline K. Limberg, Erica A. Wehrwein, and Blair D. Johnson. "Role of the carotid body chemoreceptors in glucose homeostasis and thermoregulation in humans." Journal of Physiology 596, no. 15 (March 5, 2018): 3079–85. http://dx.doi.org/10.1113/jp274354.

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Argyropoulos, George, and Mary-Ellen Harper. "Invited Review: Uncoupling proteins and thermoregulation." Journal of Applied Physiology 92, no. 5 (May 1, 2002): 2187–98. http://dx.doi.org/10.1152/japplphysiol.00994.2001.

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Energy balance in animals is a metabolic state that exists when total body energy expenditure equals dietary energy intake. Energy expenditure, or thermogenesis, can be subcategorized into groups of obligatory and facultative metabolic processes. Brown adipose tissue (BAT), through the activity of uncoupling protein 1 (UCP1), is responsible for nonshivering thermogenesis, a major component of facultative thermogenesis in newborn humans and in small mammals. UCP1, found in the mitochondrial inner membrane in BAT, uncouples energy substrate oxidation from mitochondrial ATP production and hence results in the loss of potential energy as heat. Mice that do not express UCP1 (UCP1 knockouts) are markedly cold sensitive. The recent identification of four new homologs to UCP1 expressed in BAT, muscle, white adipose tissue, brain, and other tissues has been met by tremendous scientific interest. The hypothesis that the novel UCPs may regulate thermogenesis and/or fatty acid metabolism guides investigations worldwide. Despite several hundred publications on the new UCPs, there are a number of significant controversies, and only a limited understanding of their physiological and biochemical properties has emerged. The discovery of UCP orthologs in fish, birds, insects, and even plants suggests the widespread importance of their metabolic functions. Answers to fundamental questions regarding the metabolic functions of the new UCPs are thus pending and more research is needed to elucidate their physiological functions. In this review, we discuss recent findings from mammalian studies in an effort to identify potential patterns of function for the UCPs.

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Yu, Hsing Cheng, Bo Yi Li, Szu Ju Li, Chin Tien Yang, and Wei Chen. "Development of Portable Microclimate Water-Cooled Thermoregulation Systems for Active Stokehold Protective Garments." Applied Mechanics and Materials 419 (October 2013): 756–60. http://dx.doi.org/10.4028/www.scientific.net/amm.419.756.

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The active stokehold protective garments (ASPG) can remove body heat of ship stokehold operators working in confined and extremely hot environment via conductive heat exchange from circulating water-cooled fluid next to the skin through the body-temperature-monitoring method. Hence, portable microclimate water-cooled thermoregulation systems (MWCTS) for the ASPG have been developed by using programmable embedded system-on-chip (PSoC) in this paper. The ASPG have advantages of longer cooling periods, better temperature-controlled capability, and excellent thermal somatosensory comfort. Furthermore, they could allow users to adjust comfortable temperature and also maintain long-term constant temperature by monitoring human temperature in portable MWCTS. Additionally, optimal control algorithm may enhance system efficiency to reduce the power consumption and extend the operating time effectively; thus, the velocity and temperature closed-loop control systems have also been improved in the portable MWCTS for the ASPG. Consequently, several experiments have been implemented and explored the impact of the heat transfer rate and verified the feasibility of the MWCTS for ASPF.

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Smith, Jacqueline, Gary Alcock, and Kim Usher. "Temperature Measurement in the Preterm and Term Neonate: A Review of the Literature." Neonatal Network 32, no. 1 (2013): 16–25. http://dx.doi.org/10.1891/0730-0832.32.1.16.

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The maintenance of a constant body temperature is important to all humans but even more so for newborn babies (neonates), especially those born pre-term. Because accurate measurement of body temperature is an important component of thermoregulation management in the neonate, a review of the literature was undertaken to determine the most appropriate method and site of temperature measurement in both the preterm and term neonate. The available evidence indicates that the axilla remains the most common place for temperature measurement.

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Bischof, John C., and Kenneth R. Diller. "From Nanowarming to Thermoregulation: New Multiscale Applications of Bioheat Transfer." Annual Review of Biomedical Engineering 20, no. 1 (June 4, 2018): 301–27. http://dx.doi.org/10.1146/annurev-bioeng-071516-044532.

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This review explores bioheat transfer applications at multiple scales from nanoparticle (NP) heating to whole-body thermoregulation. For instance, iron oxide nanoparticles are being used for nanowarming, which uniformly and quickly rewarms 50–80-mL (≤5-cm-diameter) vitrified systems by coupling with radio-frequency (RF) fields where standard convective warming fails. A modification of this approach can also be used to successfully rewarm cryopreserved fish embryos (∼0.8 mm diameter) by heating previously injected gold nanoparticles with millisecond pulsed laser irradiation where standard convective warming fails. Finally, laser-induced heating of gold nanoparticles can improve the sensitivity of lateral flow assays (LFAs) so that they are competitive with laboratory tests such as the enzyme-linked immunosorbent assay. This approach addresses the main weakness of LFAs, which are otherwise the cheapest, easiest, and fastest to use point-of-care diagnostic tests in the world. Body core temperature manipulation has now become possible through selective thermal stimulation (STS) approaches. For instance, simple and safe heating of selected areas of the skin surface can open arteriovenous anastomosis flow in glabrous skin when it is not already established, thereby creating a convenient and effective pathway to induce heat flow between the body core and environment. This has led to new applications of STS to increase or decrease core temperatures in humans and animals to assist in surgery (perioperative warming), to aid ischemic stress recovery (cooling), and even to enhance the quality of sleep. Together, these multiscale applications of nanoparticle heating and thermoregulation point to dramatic opportunities for translation and impact in these prophylactic, preservative, diagnostic, and therapeutic applications of bioheat transfer.

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Porter, Craig, Elisabet Børsheim, and Labros S. Sidossis. "Does Adipose Tissue Thermogenesis Play a Role in Metabolic Health?" Journal of Obesity 2013 (2013): 1–4. http://dx.doi.org/10.1155/2013/204094.

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The function ascribed to brown adipose tissue in humans has long been confined to thermoregulation in neonates, where this thermogenic capacity was thought lost with maturation. Recently, brown adipose tissue depots have been identified in adult humans. The significant oxidative capacity of brown adipocytes and the ability of their mitochondria to respire independently of ATP production, has led to renewed interest in the role that these adipocytes play in human energy metabolism. In our view, there is a need for robust physiological studies determining the relationship between molecular signatures of brown adipose tissue, adipose tissue mitochondrial function, and whole body energy metabolism, in order to elucidate the significance of thermogenic adipose tissue in humans. Until such information is available, the role of thermogenic adipose tissue in human metabolism and the potential that these adipocytes may prevent or treat obesity and metabolic diseases in humans will remain unknown. In this article, we summarize the recent literature pertaining to brown adipose tissue function with the aims of drawing the readers’ attention to the lack of data concerning the role of brown adipocytes in human physiology, and to the potential limitations of current research strategies.

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Malkinson, T. J., K. E. Cooper, and W. L. Veale. "Physiological changes during thermoregulation and fever in urethan-anesthetized rats." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 255, no. 1 (July 1, 1988): R73—R81. http://dx.doi.org/10.1152/ajpregu.1988.255.1.r73.

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Adult male Wistar rats were anesthetized with urethan (1.5 g/kg). They were unable to maintain body temperature (Tb) in a warm (32 degrees C) or cool (9 degrees C) environment or at a laboratory room temperature of 22 degrees C. Tb was allowed to fall to 35.8, 34.5, or 33.3 degrees C, and prostaglandin E1 (PGE1, 400 ng) was delivered into a lateral cerebral ventricle. An immediate feverlike rise in Tb resulted, accompanied by vigorous shivering. Animals were vasoconstricted throughout. When Tb was raised to and maintained at 38.3 or 39.5 degrees C, animals also responded with a fever; however, the magnitude of the fever diminished as the starting Tb increased. In a series of experiments in which Tb was maintained (36.8-37.4 degrees C) by means of a heating pad, PGE1 delivered into a lateral cerebral ventricle or into the anterior hypothalamus caused a dose-dependent change in Tb, which was similar in time of onset, magnitude, and duration to that observed in conscious animals. This fever was accompanied by shivering and increased O2 uptake, heart rate, arterial blood pressure, respiratory rate, and intracranial pressure during the rising phase of the fever, and vasodilation of the paws occurred during defeveresence. Animals were also able to develop a dose-dependent rise in Tb in response to purified human interleukin 1.

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Blais, Anne, Catherine Chaumontet, Dalila Azzout-Marniche, Julien Piedcoq, Gilles Fromentin, Claire Gaudichon, Daniel Tomé, and Patrick C. Even. "Low-protein diet-induced hyperphagia and adiposity are modulated through interactions involving thermoregulation, motor activity, and protein quality in mice." American Journal of Physiology-Endocrinology and Metabolism 314, no. 2 (February 1, 2018): E139—E151. http://dx.doi.org/10.1152/ajpendo.00318.2017.

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Low protein (LP)-containing diets can induce overeating in rodents and possibly in humans in an effort to meet protein requirement, but the effects on energy expenditure (EE) are unclear. The present study evaluated the changes induced by reducing dietary protein from 20% to 6%—using either soy protein or casein—on energy intake, body composition, and EE in mice housed at 22°C or at 30°C (thermal neutrality). LP feeding increased energy intake and adiposity, more in soy-fed than in casein-fed mice, but also increased EE, thus limiting fat accumulation. The increase in EE was due mainly to an increase in spontaneous motor activity related to EE and not to thermoregulation. However, the high cost of thermoregulation at 22°C and the subsequent heat exchanges between nonshivering thermogenesis, motor activity, and feeding induced large differences in adaptation between mice housed at 22°C and at 30°C.

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Shrestha, S., D. B. Gurung, and K. C. Gokul. "Mathematical modeling of temperature variation in breast tissue with and without tumor/cyst during menstrual cycle." Mathematical Modeling and Computing 8, no. 2 (2021): 192–202. http://dx.doi.org/10.23939/mmc2021.02.192.

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The thermoregulation of human female body is influenced by hormonal and physiological changes in the body during the menstrual cycle. The fluctuation of estrogen and progesterone hormones, release in the follicular phase and the luteal phase of menstrual cycle, respectively play an important role in the growth of breast ducts and lobules (milk glands). The imbalance of these hormones causes breast tumors/cysts. The body core temperature, blood perfusion and metabolism rate are higher in the luteal phase than the follicular phase of menstrual cycle. In the present work, a tumor/cyst is assumed to be in the glandular layer. A two-dimensional Pennes bioheat equation is solved to find the temperature variation in breast tissue with and without tumor/cyst during the menstrual cycle by using the finite element method. The results show that the temperature of each layer of breast tissue in the luteal phase is higher than the follicular phase in the case of normal breast, tumorous breast and breast with cyst.

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Journal articles on the topic 'Thermoregulation of the human body'

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