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Namisnak LH, Khoshnevis S, Diller KR. Interdependency of Core Temperature and Glabrous Skin Blood Flow in Human Thermoregulation Function: A Pilot Study. J Biomech Eng 2023; 145:041010. [PMID: 36305625 PMCID: PMC9791667 DOI: 10.1115/1.4056110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/20/2022] [Indexed: 12/30/2022]
Abstract
Human thermoregulation is governed by a complex, nonlinear feedback control system. The system consists of thermoreceptors, a controller, and effector mechanisms for heat exchange that coordinate to maintain a central core temperature. A principal route for heat flow between the core and the environment is via convective circulation of blood to arteriovenous anastomoses located in glabrous skin of the hands and feet. This paper presents new human experimental data for thermoregulatory control behavior along with a coupled, detailed control system model specific to the interdependent actions of core temperature and glabrous skin blood flow (GSBF) under defined transient environmental thermal stress. The model was tuned by a nonlinear least-squared curve fitting algorithm to optimally fit the experimental data. Transient GSBF in the model is influenced by core temperature, nonglabrous skin temperature, and the application of selective thermal stimulation. The core temperature in the model is influenced by integrated heat transfer across the nonglabrous body surface and GSBF. Thus, there is a strong cross-coupling between GSBF and core temperature in thermoregulatory function. Both variables include a projection term in the model based on the average rates of their change. Six subjects each completed two thermal protocols to generate data to which the common model was fit. The model coefficients were unique to each of the twelve data sets but produced an excellent agreement between the model and experimental data for the individual trials. The strong match between the model and data confirms the mathematical structure of the control algorithm.
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Affiliation(s)
- Laura H. Namisnak
- Department of Biomedical Engineering, The University of Texas at Austin, 107 West Dean Keeton Street Stop C0800, Austin, TX 78712
| | - Sepideh Khoshnevis
- Department of Biomedical Engineering, The University of Texas at Austin, 107 West Dean Keeton Street Stop C0800, Austin, TX 78712
| | - Kenneth R. Diller
- Department of Biomedical Engineering, The University of Texas at Austin, 107 West Dean Keeton Street Stop C0800, Austin, TX 78712
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2
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Dang S, Xue H, Zhang X, Zhong C, Tao C. Research on the human heat transfer model of Chinese pilots and experimental verification of model correctness. Neural Comput Appl 2022. [DOI: 10.1007/s00521-020-05293-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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3
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Haghayegh S, Khoshnevis S, Smolensky MH, Hermida RC, Castriotta RJ, Schernhammer E, Diller KR. Novel
temperature‐controlled
sleep system to improve sleep: a p
roof‐of‐concept
study. J Sleep Res 2022; 31:e13662. [DOI: 10.1111/jsr.13662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/14/2022] [Accepted: 05/13/2022] [Indexed: 01/08/2023]
Affiliation(s)
- Shahab Haghayegh
- Channing Division of Network Medicine Brigham and Women's Hospital and Harvard Medical School Boston Massachusetts USA
- Department of Biomedical Engineering Cockrell School of Engineering, The University of Texas at Austin Austin Texas USA
| | - Sepideh Khoshnevis
- Department of Biomedical Engineering Cockrell School of Engineering, The University of Texas at Austin Austin Texas USA
| | - Michael H. Smolensky
- Department of Biomedical Engineering Cockrell School of Engineering, The University of Texas at Austin Austin Texas USA
- Department of Internal Medicine, Division of Cardiology McGovern School of Medicine, The University of Texas Health Science Center at Houston Houston Texas USA
| | - Ramon C. Hermida
- Department of Biomedical Engineering Cockrell School of Engineering, The University of Texas at Austin Austin Texas USA
- Bioengineering and Chronobiology Laboratories Atlantic Research Center for Telecommunication Technologies, University of Vigo Vigo Spain
| | - Richard J. Castriotta
- Division of Pulmonary, Critical Care and Sleep Medicine Keck School of Medicine, University of Southern California Los Angeles California USA
| | - Eva Schernhammer
- Channing Division of Network Medicine Brigham and Women's Hospital and Harvard Medical School Boston Massachusetts USA
- Department of Epidemiology Center for Public Health, Medical University of Vienna Vienna Austria
- Department of Epidemiology Harvard TH Chan School of Public Health Boston Massachusetts USA
| | - Kenneth R. Diller
- Department of Biomedical Engineering Cockrell School of Engineering, The University of Texas at Austin Austin Texas USA
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4
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Duh M, Skok K, Perc M, Markota A, Gosak M. Computational modeling of targeted temperature management in post-cardiac arrest patients. Biomech Model Mechanobiol 2022; 21:1407-1424. [PMID: 35763192 DOI: 10.1007/s10237-022-01598-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 05/23/2022] [Indexed: 11/28/2022]
Abstract
Our core body temperature is held around [Formula: see text]C by an effective internal thermoregulatory system. However, various clinical scenarios have a more favorable outcome under external temperature regulation. Therapeutic hypothermia, for example, was found beneficial for the outcome of resuscitated cardiac arrest patients due to its protection against cerebral ischemia. Nonetheless, practice shows that outcomes of targeted temperature management vary considerably in dependence on individual tissue damage levels and differences in therapeutic strategies and protocols. Here, we address these differences in detail by means of computational modeling. We develop a multi-segment and multi-node thermoregulatory model that takes into account details related to specific post-cardiac arrest-related conditions, such as thermal imbalances due to sedation and anesthesia, increased metabolic rates induced by inflammatory processes, and various external cooling techniques. In our simulations, we track the evolution of the body temperature in patients subjected to post-resuscitation care, with particular emphasis on temperature regulation via an esophageal heat transfer device, on the examination of the alternative gastric cooling with ice slurry, and on how anesthesia and the level of inflammatory response influence thermal behavior. Our research provides a better understanding of the heat transfer processes and therapies used in post-cardiac arrest patients.
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Affiliation(s)
- Maja Duh
- Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, 2000, Maribor, Slovenia
| | - Kristijan Skok
- Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.,Department of Pathology, General Hospital Graz II, Location West, Göstinger Straße 22, 8020, Graz, Austria
| | - Matjaž Perc
- Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, 2000, Maribor, Slovenia.,Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, 404332, Taiwan.,Alma Mater Europaea, Slovenska ulica 17, 2000, Maribor, Slovenia.,Complexity Science Hub Vienna, Josefstädterstraße 39, 1080, Vienna, Austria
| | - Andrej Markota
- Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.,Medical Intensive Care Unit, University Medical Centre Maribor, Ljubljanska 5, 2000, Maribor, Slovenia
| | - Marko Gosak
- Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, 2000, Maribor, Slovenia. .,Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.
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5
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Namisnak LH, Haghayegh S, Khoshnevis S, Diller KR. Bioheat Transfer Basis of Human Thermoregulation: Principles and Applications. JOURNAL OF HEAT TRANSFER 2022; 144:031203. [PMID: 35833149 PMCID: PMC8823203 DOI: 10.1115/1.4053195] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 12/06/2021] [Indexed: 05/29/2023]
Abstract
Thermoregulation is a process that is essential to the maintenance of life for all warm-blooded mammalian and avian species. It sustains a constant core body temperature in the face of a wide array of environmental thermal conditions and intensity of physical activities that generate internal heat. A primary component of thermoregulatory function is the movement of heat between the body core and the surface via the circulation of blood. The peripheral vasculature acts as a forced convection heat exchanger between blood and local peripheral tissues throughout the body enabling heat to be convected to the skin surface where is may be transferred to and from the environment via conduction, convection, radiation, and/or evaporation of water as local conditions dictate. Humans have evolved a particular vascular structure in glabrous (hairless) skin that is especially well suited for heat exchange. These vessels are called arteriovenous anastomoses (AVAs) and can vasodilate to large diameters and accommodate high flow rates. We report herein a new technology based on a physiological principle that enables simple and safe access to the thermoregulatory control system to allow manipulation of thermoregulatory function. The technology operates by applying a small amount of heating local to control tissue on the body surface overlying the cerebral spine that upregulates AVA perfusion. Under this action, heat exchangers can be applied to glabrous skin, preferably on the palms and soles, to alter the temperature of elevated blood flow prior to its return to the core. Therapeutic and prophylactic applications are discussed.
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Affiliation(s)
- Laura H Namisnak
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712
| | - Shahab Haghayegh
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712; Department of Biostatics, T.H. Chan School of Public Health, Harvard Medical School, Boston, MA 02138
| | - Sepideh Khoshnevis
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712
| | - Kenneth R Diller
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712
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Tripathi J, Vasu B, Bég OA, Gorla RSR, Kameswaran PK. Computational simulation of rheological blood flow containing hybrid nanoparticles in an inclined catheterized artery with stenotic, aneurysmal and slip effects. Comput Biol Med 2021; 139:105009. [PMID: 34775156 DOI: 10.1016/j.compbiomed.2021.105009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/29/2021] [Accepted: 10/29/2021] [Indexed: 11/15/2022]
Abstract
Influenced by nano-drug delivery applications, the present article considers the collective effects of hybrid biocompatible metallic nanoparticles (Silver and Copper), a stenosis and an aneurysm on the unsteady blood flow characteristics in a catheterized tapered inclined artery. The non-Newtonian Carreau fluid model is deployed to represent the hemorheological characteristics in the arterial region. A modified Tiwari-Das volume fraction model is adopted for nanoscale effects. The permeability of the arterial wall and the inclination of the diseased artery are taken into account. The nanoparticles are also considered to have various shapes (bricks, cylinders, platelets, blades) and therefore the influence of different shape parameters is discussed. The conservation equations for mass, linear momentum and energy are normalized by employing suitable non-dimensional variables. The transformed equations with associated boundary conditions are solved numerically using the FTCS method. Key hemodynamic characteristics i.e. velocity, temperature, flow rate, wall shear stress (WSS) in stenotic and aneurysm region for a particular critical height of the stenosis, are computed. Hybrid nanoparticles (Ag-Cu/Blood) accelerate the axial flow and increase temperatures significantly compared with unitary nanoparticles (Ag/blood), at both the stenosis and aneurysm segments. Axial velocity, temperature and flow rate are all enhanced with greater nanoparticle shape factor. Axial velocity, temperature, wall shear stress and flow rate magnitudes are always comparatively higher at the aneurysm region compared with the stenotic segment. The simulations provide novel insights into the performance of different nanoparticle geometries and also rheological behaviour in realistic nano-pharmaco-dynamic transport and percutaneous coronary intervention (PCI).
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Affiliation(s)
- Jayati Tripathi
- Department of Mathematics, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, 211004, U.P, India
| | - B Vasu
- Department of Mathematics, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, 211004, U.P, India.
| | - O Anwar Bég
- Department of Mechanical and Aeronautical Engineering, Salford University, Salford, M54WT, UK
| | - Rama Subba Reddy Gorla
- Department of Aeronautics and Astronautics, Air Force Institute of Technology, Wright Patterson Air Force Base, Dayton, OH, 45433, USA
| | - Peri K Kameswaran
- Department of Mathematics, School of Advanced Sciences, VIT University, Vellore, 632014, India
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7
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Tripathi J, Vasu B, Bég OA, Gorla RSR. Unsteady hybrid nanoparticle-mediated magneto-hemodynamics and heat transfer through an overlapped stenotic artery: Biomedical drug delivery simulation. Proc Inst Mech Eng H 2021; 235:1175-1196. [PMID: 34154464 DOI: 10.1177/09544119211026095] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Two-dimensional laminar hemodynamics through a diseased artery featuring an overlapped stenosis was simulated theoretically and computationally. This study presented a mathematical model for the unsteady blood flow with hybrid biocompatible nanoparticles (Silver and Gold) inspired by drug delivery applications. A modified Tiwari-Das volume fraction model was adopted for nanoscale effects. Motivated by the magneto-hemodynamics effects, a uniform magnetic field was applied in the radial direction to the blood flow. For realistic blood behavior, Reynolds' viscosity model was applied in the formulation to represent the temperature dependency of blood. Fourier's heat conduction law was assumed and heat generation effects were included. Therefore, the governing equations were an extension of the Navier-Stokes equations with magneto-hydrodynamic body force included. The two-dimensional governing equations were transformed and normalized with appropriate variables, and the mild stenotic approximation was implemented. The strongly nonlinear nature of the resulting dimensionless boundary value problem required a robust numerical method, and therefore the FTCS algorithm was deployed. Validation of solutions for the particular case of constant viscosity and non-magnetic blood flow was included. Using clinically realistic hemodynamic data, comprehensive solutions were presented for silver, and silver-gold hybrid mediated blood flow. A comparison between silver and hybrid nanofluid was also included, emphasizing the use of hybrid nanoparticles for minimizing the hemodynamics. Enhancement in magnetic parameter decelerated the axial blood flow in stenotic region. Colored streamline plots for blood, silver nano-doped blood, and hybrid nano-doped blood were also presented. The simulations were relevant to the diffusion of nano-drugs in magnetic targeted treatment of stenosed arterial diseases.
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Affiliation(s)
- Jayati Tripathi
- Department of Mathematics, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh, India
| | - Buddakkagari Vasu
- Department of Mathematics, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh, India
| | - Osman Anwar Bég
- Department of Mechanical and Aeronautical Engineering, School of Science, Engineering and Environment (SEE), Newton building, Salford University, Manchester, UK
| | - Rama Subba Reddy Gorla
- Department of Aeronautics and Astronautics, Air Force Institute of Technology, Wright Patterson Air Force Base, Dayton, OH, USA
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8
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El Kadri M, De Oliveira F, Inard C, Demouge F. New neurophysiological human thermal model based on thermoreceptor responses. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2020; 64:2007-2017. [PMID: 32820392 DOI: 10.1007/s00484-020-01990-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 06/11/2023]
Abstract
A new neurophysiological human thermal model based on thermoreceptor responses, the NHTM model, has been developed to predict regulatory responses and physiological variables in asymmetric transient environments. The passive system is based on Wissler's model, which is more complex and refined. Wissler's model segments the human body into 21 cylindrical parts. Each part is divided into 21 layers, 15 for the tissues and 6 for clothes, and each layer is divided into 12 angular sectors. Thus, we have 3780 nodes for the tissues and 1512 for clothes. The passive system simulates heat exchange within the body and between the body and the surroundings. The active system is composed of the thermoregulatory mechanisms, i.e., skin blood flow, shivering thermogenesis, and sweating. The skin blood flow model and the shivering model are based on thermoreceptor responses. The sweating model is that of Fiala et al. and is based on error signals. The NHTM model was compared with Wissler's model, and the results showed that a calculation based on neurophysiology can improve the performance of the thermoregulation model. The NHTM model was more accurate in the prediction of mean skin temperature, with a mean absolute error of 0.27 °C versus 0.80 °C for the original Wissler model. The prediction accuracy of the NHTM model for local skin temperatures and core temperature could be improved via an optimization method to prove the ability of the new thermoregulation model to fit with the physiological characteristics of different populations.
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Affiliation(s)
- Mohamad El Kadri
- Centre Scientifique et Technique du Bâtiment CSTB, Marne-la-Vallée, France.
- Laboratory of Engineering Sciences for Environment (LaSIE), UMR CNRS 7356, La Rochelle University, La Rochelle, France.
| | | | - Christian Inard
- Laboratory of Engineering Sciences for Environment (LaSIE), UMR CNRS 7356, La Rochelle University, La Rochelle, France
| | - François Demouge
- Centre Scientifique et Technique du Bâtiment CSTB, Marne-la-Vallée, France
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Alzeer AH, Wissler EH. Theoretical analysis of evaporative cooling of classic heat stroke patients. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2018; 62:1567-1574. [PMID: 29777308 DOI: 10.1007/s00484-018-1551-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/31/2018] [Accepted: 04/18/2018] [Indexed: 06/08/2023]
Abstract
Heat stroke is a serious health concern globally, which is associated with high mortality. Newer treatments must be designed to improve outcomes. The aim of this study is to evaluate the effect of variations in ambient temperature and wind speed on the rate of cooling in a simulated heat stroke subject using the dynamic model of Wissler. We assume that a 60-year-old 70-kg female suffers classic heat stroke after walking fully exposed to the sun for 4 h while the ambient temperature is 40 °C, relative humidity is 20%, and wind speed is 2.5 m/s-1. Her esophageal and skin temperatures are 41.9 and 40.7 °C at the time of collapse. Cooling is accomplished by misting with lukewarm water while exposed to forced airflow at a temperature of 20 to 40 °C and a velocity of 0.5 or 1 m/s-1. Skin blood flow is assumed to be either normal, one-half of normal, or twice normal. At wind speed of 0.5 m/s-1 and normal skin blood flow, the air temperature decreased from 40 to 20 °C, increased cooling, and reduced time required to reach to a desired temperature of 38 °C. This relationship was also maintained in reduced blood flow states. Increasing wind speed to 1 m/s-1 increased cooling and reduced the time to reach optimal temperature both in normal and reduced skin blood flow states. In conclusion, evaporative cooling methods provide an effective method for cooling classic heat stroke patients. The maximum heat dissipation from the simulated model of Wissler was recorded when the entire body was misted with lukewarm water and applied forced air at 1 m/s at temperature of 20 °C.
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Affiliation(s)
- Abdulaziz H Alzeer
- Department of Critical Care, King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia.
| | - E H Wissler
- Department of Chemical Engineering, University of Texas, Austin, TX, USA
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Su Y, Yang J, Song G, Li R, Xiang C, Li J. Development of a numerical model to predict physiological strain of firefighter in fire hazard. Sci Rep 2018; 8:3628. [PMID: 29483557 PMCID: PMC5827774 DOI: 10.1038/s41598-018-22072-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 02/07/2018] [Indexed: 11/20/2022] Open
Abstract
This paper aims to develop a numerical model to predict heat stress of firefighter under low-level thermal radiation. The model integrated a modified multi-layer clothing model with a human thermoregulation model. We took the coupled radiative and conductive heat transfer in the clothing, the size-dependent heat transfer in the air gaps, and the controlling active and controlled passive thermal regulation in human body into consideration. The predicted core temperature and mean skin temperature from the model showed a good agreement with the experimental results. Parametric study was conducted and the result demonstrated that the radiative intensity had a significant influence on the physiological heat strain. The existence of air gap showed positive effect on the physiological heat strain when air gap size is small. However, when the size of air gap exceeds 6 mm, a different trend was observed due to the occurrence of natural convection. Additionally, the time length for the existence of the physiological heat strain was greater than the existence of the skin burn under various heat exposures. The findings obtained in this study provide a better understanding of the physiological strain of firefighter and shed light on textile material engineering for achieving higher protective performance.
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Affiliation(s)
- Yun Su
- College of Fashion and Design, Donghua University, Shanghai, 200051, China
- Iowa State University, Ames, 50010, Iowa, USA
| | - Jie Yang
- Iowa State University, Ames, 50010, Iowa, USA
| | - Guowen Song
- Iowa State University, Ames, 50010, Iowa, USA.
| | - Rui Li
- Iowa State University, Ames, 50010, Iowa, USA
| | | | - Jun Li
- College of Fashion and Design, Donghua University, Shanghai, 200051, China
- Key Laboratory of Clothing Design and Technology, Donghua University, Ministry of Education, Shanghai, 200051, China
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11
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Tian Y, Li J, Zhang H, Xue L, Lei W, Ding L. Thermal protection study of bladder compensatory suit using a heat transfer model. Work 2017; 58:415-425. [PMID: 29254123 DOI: 10.3233/wor-172638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The bladder compensatory suit (BCS) is important individual protective equipment for pilots' activities in a high-flying environment. The layout and thermal diffusion ability of the bladder directly affects the thermal comfort of pilots in flight. OBJECTIVE (1) Established and verified a human-compensatory suit-environment heat transfer model; (2) Used the model to study the human thermal variation of each segment in hot conditions and clothing. METHODS To verify the two-dimensional heat transfer model, simulated data of body temperature were compared with experimental results under the same conditions (AT: 40/45°C, ordinary clothing). The model could be used to calculate the temperature variation of each body segment in three environments temperature (28°C, 35°C and 40°C) and three types of clothing (naked, ordinary clothing, BCS). RESULTS The results showed that: (1) the bladder significantly affected sweating speed and skin temperature, as well as core temperature; (2) the skin temperature of the area covered by the bladder was difficult to reduce by the thermal regulation system. It was because sweat secretion was inhibited, thus, to limit evaporation. CONCLUSIONS The model could be used as a reference for the thermal protection design of bladder compensatory suit. SUMMARY The bladder compensatory suit (BCS) is important individual protective equipment for pilots activities in a high-flying environment, and its layout directly affects the thermal comfort. Based on a two-dimensional thermal regulation system model, a body-clothing-environment heat transfer model was established. The model was used to calculate the temperature and sweat variation of each body segment in different environments and clothing.
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Affiliation(s)
- Yinsheng Tian
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Jing Li
- Department of Integrated System Engineering, Ohio State University, Columbus, OH, USA
| | - Haibo Zhang
- AVIC Aerospace Life-Support Industries, LTD, Xiangfan, China
| | - Lihao Xue
- Institute of Aviation Medicine, Air Force, Beijing, China
| | - Wen Lei
- Chongqing Qingping Machinery CO., LTD, Chongqing, China
| | - Li Ding
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China
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12
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Hodges GJ, Mallette MM, Martin ZT, Del Pozzi AT. Effect of sympathetic nerve blockade on low-frequency oscillations of forearm and leg skin blood flow in healthy humans. Microcirculation 2017. [DOI: 10.1111/micc.12388] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Gary J. Hodges
- Environmental Ergonomics Laboratory; Brock University; St Catharines ON Canada
| | - Matthew M. Mallette
- Environmental Ergonomics Laboratory; Brock University; St Catharines ON Canada
| | - Zachary T. Martin
- Integrative Exercise Physiology Laboratory; Ball State University; Muncie IN USA
| | - Andrew T. Del Pozzi
- Integrative Exercise Physiology Laboratory; Ball State University; Muncie IN USA
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13
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Fu M, Weng W, Chen W, Luo N. Review on modeling heat transfer and thermoregulatory responses in human body. J Therm Biol 2016; 62:189-200. [DOI: 10.1016/j.jtherbio.2016.06.018] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 06/29/2016] [Indexed: 11/25/2022]
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14
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Havenith G, Fiala D. Thermal Indices and Thermophysiological Modeling for Heat Stress. Compr Physiol 2015; 6:255-302. [DOI: 10.1002/cphy.c140051] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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15
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Diller KR. Heat Transfer in Health and Healing. JOURNAL OF HEAT TRANSFER 2015; 137:1030011-10300112. [PMID: 26424899 PMCID: PMC4462861 DOI: 10.1115/1.4030424] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 04/01/2015] [Indexed: 05/08/2023]
Abstract
Our bodies depend on an exquisitely sensitive and refined temperature control system to maintain a state of health and homeostasis. The exceptionally broad range of physical activities that humans engage in and the diverse array of environmental conditions we face require remarkable strategies and mechanisms for regulating internal and external heat transfer processes. On the occasions for which the body suffers trauma, therapeutic temperature modulation is often the approach of choice for reversing injury and inflammation and launching a cascade of healing. The focus of human thermoregulation is maintenance of the body core temperature within a tight range of values, even as internal rates of energy generation may vary over an order of magnitude, environmental convection, and radiation heat loads may undergo large changes in the absence of any significant personal control, surface insulation may be added or removed, all occurring while the body's internal thermostat follows a diurnal circadian cycle that may be altered by illness and anesthetic agents. An advanced level of understanding of the complex physiological function and control of the human body may be combined with skill in heat transfer analysis and design to develop life-saving and injury-healing medical devices. This paper will describe some of the challenges and conquests the author has experienced related to the practice of heat transfer for maintenance of health and enhancement of healing processes.
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Affiliation(s)
- Kenneth R Diller
- Department of Biomedical Engineering, The University of Texas at Austin , 107 West Dean Keeton Street , BME 4.202A , Austin, TX 78712-1084 e-mail:
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16
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Therapeutic Recruitment of Thermoregulation in Humans by Selective Thermal Stimulation along the Spine. ADVANCES IN HEAT TRANSFER 2015. [DOI: 10.1016/bs.aiht.2015.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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