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Riddell EA, Burger IJ, Tyner-Swanson TL, Biggerstaff J, Muñoz MM, Levy O, Porter CK. Parameterizing mechanistic niche models in biophysical ecology: a review of empirical approaches. J Exp Biol 2023; 226:jeb245543. [PMID: 37955347 DOI: 10.1242/jeb.245543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
Mechanistic niche models are computational tools developed using biophysical principles to address grand challenges in ecology and evolution, such as the mechanisms that shape the fundamental niche and the adaptive significance of traits. Here, we review the empirical basis of mechanistic niche models in biophysical ecology, which are used to answer a broad array of questions in ecology, evolution and global change biology. We describe the experiments and observations that are frequently used to parameterize these models and how these empirical data are then incorporated into mechanistic niche models to predict performance, growth, survival and reproduction. We focus on the physiological, behavioral and morphological traits that are frequently measured and then integrated into these models. We also review the empirical approaches used to incorporate evolutionary processes, phenotypic plasticity and biotic interactions. We discuss the importance of validation experiments and observations in verifying underlying assumptions and complex processes. Despite the reliance of mechanistic niche models on biophysical theory, empirical data have and will continue to play an essential role in their development and implementation.
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Affiliation(s)
- Eric A Riddell
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Isabella J Burger
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Tamara L Tyner-Swanson
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Justin Biggerstaff
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Martha M Muñoz
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511, USA
| | - Ofir Levy
- Faculty of Life Sciences, School of Zoology, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Cody K Porter
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
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2
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Clark RW, Bakken GS, Reed EJ, Soni A. Pit viper thermography: the pit organ used by crotaline snakes to detect thermal contrast has poor spatial resolution. J Exp Biol 2022; 225:285597. [PMID: 36453156 DOI: 10.1242/jeb.244478] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 11/23/2022] [Indexed: 12/03/2022]
Abstract
Pit vipers detect infrared radiation by means of temperature contrasts created on their pit organ membranes. Signals from pit organs integrate with visual signals in the optic tectum, leading to the conjecture that the facial pits operate as an extension of the visual system. Because similar mechanisms underlie thermal imaging technology, imagery from thermal cameras is often used to infer how pit vipers perceive their environment. However, pit organs lack a focusing mechanism, and biophysical models predict that pit organs should have poor spatial resolution compared with thermal imaging cameras. Nevertheless, behavioral studies occasionally suggest pits may have better resolution than predicted by biophysical models, indicating that processing in the central nervous system may improve imaging. To estimate the spatial resolution of the neural image informing behavior, we recorded snake responses evoked by targets moving across backgrounds composed of two contrasting temperatures with an average temperature equal to the target temperature. An unresolved background would appear uniform; thus, the target would be detectable only if the background pattern were resolved. Western rattlesnakes (Crotalus oreganus) displayed no statistically significant responses to targets presented in front of patterned backgrounds, regardless of the temperature contrasts or spatial frequencies within the background, but responded strongly to targets presented in front of homogeneous backgrounds. We found no evidence that the pit organ system can resolve spatial details subtending an angle of 9 deg or less. We discuss the implications of these results for understanding pit organ function in ecologically relevant habitats with thermal heterogeneity.
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Affiliation(s)
- Rulon W Clark
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - George S Bakken
- Department of Biology, San Diego State University, San Diego, CA 92182, USA.,4431 East Park Avenue, Terre Haute, IN 47805, USA
| | - Evan J Reed
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Ashana Soni
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
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3
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O'Brien F, Staunton CA, Barrett-Jolley R. Systemic application of the transient receptor potential vanilloid-type 4 antagonist GSK2193874 induces tail vasodilation in a mouse model of thermoregulation. Biol Lett 2022; 18:20220129. [PMID: 35702981 PMCID: PMC9198786 DOI: 10.1098/rsbl.2022.0129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In humans, skin is a primary thermoregulatory organ, with vasodilation leading to rapid body cooling, whereas in Rodentia the tail performs an analogous function. Many thermodetection mechanisms are likely to be involved including transient receptor potential vanilloid-type 4 (TRPV4), an ion channel with thermosensitive properties. Previous studies have shown that TRPV4 is a vasodilator by local action in blood vessels, so here, we investigated whether constitutive TRPV4 activity affects Mus muscularis tail vascular tone and thermoregulation. We measured tail blood flow by pressure plethysmography in lightly sedated M. muscularis (CD1 strain) at a range of ambient temperatures, with and without intraperitoneal administration of the blood-brain barrier crossing TRPV4 antagonist GSK2193874. We also measured heart rate (HR) and blood pressure. As expected for a thermoregulatory organ, we found that tail blood flow increased with temperature. However, unexpectedly, we found that GSK2193874 increased tail blood flow at all temperatures, and we observed changes in HR variability. Since local TRPV4 activation causes vasodilation that would increase tail blood flow, these data suggest that increases in tail blood flow resulting from the TRPV4 antagonist may arise from a site other than the blood vessels themselves, perhaps in central cardiovascular control centres.
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Affiliation(s)
- Fiona O'Brien
- Department of Musculoskeletal Ageing, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L7 8TX, UK
| | - Caroline A. Staunton
- Department of Musculoskeletal Ageing, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L7 8TX, UK
| | - Richard Barrett-Jolley
- Department of Musculoskeletal Ageing, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L7 8TX, UK
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Verduzco-Mendoza A, Bueno-Nava A, Wang D, Martínez-Burnes J, Olmos-Hernández A, Casas A, Domínguez A, Mota-Rojas D. Experimental Applications and Factors Involved in Validating Thermal Windows Using Infrared Thermography to Assess the Health and Thermostability of Laboratory Animals. Animals (Basel) 2021; 11:3448. [PMID: 34944225 PMCID: PMC8698170 DOI: 10.3390/ani11123448] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/25/2021] [Accepted: 12/01/2021] [Indexed: 12/12/2022] Open
Abstract
Evaluating laboratory animals' health and thermostability are fundamental components of all experimental designs. Alterations in either one of these parameters have been shown to trigger physiological changes that can compromise the welfare of the species and the replicability and robustness of the results obtained. Due to the nature and complexity of evaluating and managing the species involved in research protocols, non-invasive tools such as infrared thermography (IRT) have been adopted to quantify these parameters without altering them or inducing stress responses in the animals. IRT technology makes it possible to quantify changes in surface temperatures that are derived from alterations in blood flow that can result from inflammatory, stressful, or pathological processes; changes can be measured in diverse regions, called thermal windows, according to their specific characteristics. The principal body regions that were employed for this purpose in laboratory animals were the orbital zone (regio orbitalis), auricular pavilion (regio auricularis), tail (cauda), and the interscapular area (regio scapularis). However, depending on the species and certain external factors, the sensitivity and specificity of these windows are still subject to controversy due to contradictory results published in the available literature. For these reasons, the objectives of the present review are to discuss the neurophysiological mechanisms involved in vasomotor responses and thermogenesis via BAT in laboratory animals and to evaluate the scientific usefulness of IRT and the thermal windows that are currently used in research involving laboratory animals.
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Affiliation(s)
- Antonio Verduzco-Mendoza
- PhD Program in Biological and Health Sciences [Doctorado en Ciencias Biológicas y de la Salud], Universidad Autónoma Metropolitana, Mexico City 04960, Mexico;
| | - Antonio Bueno-Nava
- División of Neurosciences, Instituto Nacional de Rehabilitación-Luis Guillermo Ibarra Ibarra, (INR-LGII), Mexico City 14389, Mexico;
| | - Dehua Wang
- School of Life Sciences, Shandong University, Qingdao 266237, China;
| | - Julio Martínez-Burnes
- Animal Health Group, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Tamaulipas, Victoria City 87000, Mexico;
| | - Adriana Olmos-Hernández
- Division of Biotechnology—Bioterio and Experimental Surgery, Instituto Nacional de Rehabilitación-Luis Guillermo Ibarra Ibarra (INR-LGII), Mexico City 14389, Mexico;
| | - Alejandro Casas
- Neurophysiology, Behavior and Animal Welfare Assessment, DPAA, Xochimilco Campus, Universidad Autónoma Metropolitana (UAM), Mexico City 04960, Mexico; (A.C.); (A.D.)
| | - Adriana Domínguez
- Neurophysiology, Behavior and Animal Welfare Assessment, DPAA, Xochimilco Campus, Universidad Autónoma Metropolitana (UAM), Mexico City 04960, Mexico; (A.C.); (A.D.)
| | - Daniel Mota-Rojas
- Neurophysiology, Behavior and Animal Welfare Assessment, DPAA, Xochimilco Campus, Universidad Autónoma Metropolitana (UAM), Mexico City 04960, Mexico; (A.C.); (A.D.)
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Ryding S, Klaassen M, Tattersall GJ, Gardner JL, Symonds MRE. Shape-shifting: changing animal morphologies as a response to climatic warming. Trends Ecol Evol 2021; 36:1036-1048. [PMID: 34507845 DOI: 10.1016/j.tree.2021.07.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/14/2021] [Accepted: 07/19/2021] [Indexed: 12/19/2022]
Abstract
Many animal appendages, such as avian beaks and mammalian ears, can be used to dissipate excess body heat. Allen's rule, wherein animals in warmer climates have larger appendages to facilitate more efficient heat exchange, reflects this. We find that there is widespread evidence of 'shape-shifting' (changes in appendage size) in endotherms in response to climate change and its associated climatic warming. We re-examine studies of morphological change over time within a thermoregulatory context, finding evidence that temperature can be a strong predictor of morphological change independently of, or combined with, other environmental changes. Last, we discuss how Allen's rule, the degree of temperature change, and other ecological factors facilitate morphological change and make predictions about what animals will show shape-shifting.
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Affiliation(s)
- Sara Ryding
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria 3125, Australia.
| | - Marcel Klaassen
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria 3125, Australia
| | - Glenn J Tattersall
- Department of Biological Sciences, Brock University, 500 Glenridge Avenue, Saint Catharines, Ontario L2S 3A1, Canada
| | - Janet L Gardner
- Division of Ecology & Evolution, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Matthew R E Symonds
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria 3125, Australia
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Hankenson FC, Marx JO, Gordon CJ, David JM. Effects of Rodent Thermoregulation on Animal Models in the Research Environment. Comp Med 2018; 68:425-438. [PMID: 30458902 DOI: 10.30802/aalas-cm-18-000049] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
To best promote animal wellbeing and the efficacy of biomedical models, scientific, husbandry, and veterinary professionals must consider the mechanisms, influences, and outcomes of rodent thermoregulation in contemporary research environments. Over the last 2 decades, numerous studies have shown that laboratory mice and rats prefer temperatures that are several degrees warmer than the environments in which they typically are housed within biomedical facilities. Physiologic changes to rodents that are cage-housed under standard temperatures (20 to 26 °C) are attributed to 'cold stress' and include alterations in metabolism, cardiovascular parameters, respiration, and immunologic function. This review article describes common behavioral and physiologic adaptations of laboratory mice and rats to cold stress within modern vivaria, with emphasis on environmental enrichment and effects of anesthesia and procedural support efforts. In addition, potential interventions and outcomes for rodents are presented, relative to the importance of repeating and reproducing experiments involving laboratory rodent research models of human disease.
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Affiliation(s)
- F Claire Hankenson
- Campus Animal Resources, Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - James O Marx
- University Laboratory Animal Resources, Department of Pathobiology, School of Veterinary Medicine; University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Christopher J Gordon
- Toxicity Assessment Division, Neurotoxicology Branch, United States Environmental Protection Agency, Research Triangle Park, North Carolina, USA
| | - John M David
- Comparative Medicine, Pfizer, La Jolla, California, USA
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7
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David JM, Chen X. Evaluation of warming devices for lateral tail vein blood collection in mice (Mus musculus). J Pharmacol Toxicol Methods 2018; 94:87-93. [DOI: 10.1016/j.vascn.2018.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 06/04/2018] [Accepted: 06/08/2018] [Indexed: 10/28/2022]
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The exercise sex gap and the impact of the estrous cycle on exercise performance in mice. Sci Rep 2018; 8:10742. [PMID: 30013130 PMCID: PMC6048134 DOI: 10.1038/s41598-018-29050-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 06/21/2018] [Indexed: 01/08/2023] Open
Abstract
Exercise physiology is different in males and females. Females are poorly studied due to the complexity of the estrous cycle and this bias has created an exercise sex gap. Here, we evaluated the impact of sexual dimorphism and of the estrous cycle on muscle strength and running power of C57BL/6 mice. Like men, male mice were stronger and more powerful than females. Exercise-induced increase of O2 consumption (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{{\bf{V}}}$$\end{document}V˙O2) and CO2 production (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{{\bf{V}}}$$\end{document}V˙CO2) were equal between sexes, indicating that running economy was higher in males. Thermoregulation was also more efficient in males. In females, proestrus increased exercise \documentclass[12pt]{minimal}
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\begin{document}$$\dot{{\bf{V}}}$$\end{document}V˙O2 and \documentclass[12pt]{minimal}
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\begin{document}$$\dot{{\bf{V}}}$$\end{document}V˙CO2 at low running speeds (30–35% female \documentclass[12pt]{minimal}
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\begin{document}$$\dot{{\bf{V}}}$$\end{document}V˙O2max) and estrus worsened thermoregulation. These differences translated into different absolute and relative workloads on the treadmill, even at equal submaximal \documentclass[12pt]{minimal}
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\begin{document}$$\dot{{\bf{V}}}$$\end{document}V˙O2 and belt speeds. In summary, our results demonstrate the better muscle strength, running power and economy, and exercise-induced thermoregulation of males compared to females. Proestrus and estrus still undermined the running economy and exercise-induced thermoregulation of females, respectively. These results demonstrate an important exercise sex gap in mice.
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9
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Gong Y, Capstick M, Tillmann T, Dasenbrock C, Samaras T, Kuster N. Desktop exposure system and dosimetry for small scale in vivo radiofrequency exposure experiments. Bioelectromagnetics 2016; 37:49-61. [PMID: 26769169 DOI: 10.1002/bem.21950] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 12/03/2015] [Indexed: 11/11/2022]
Abstract
This paper describes a new approach to the risk assessment of exposure from wireless network devices, including an exposure setup and dosimetric assessment for in vivo studies. A novel desktop reverberation chamber has been developed for well-controlled exposure of mice for up to 24 h per day to address the biological impact of human exposure scenarios by wireless networks. The carrier frequency of 2.45 GHz corresponds to one of the major bands used in data communication networks and is modulated by various modulation schemes, including Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Radio Frequency Identification (RFID), and wireless local area network, etc. The system has been designed to enable exposures of whole-body averaged specific absorption rate (SAR) of up to 15 W/kg for six mice of an average weight of 25 g or of up to 320 V/m incident time-averaged fields under loaded conditions without distortion of the signal. The dosimetry for whole-body SAR and organ-averaged SAR of the exposed mice, with analysis of uncertainty and variation analysis, is assessed. The experimental dosimetry based on temperature measurement agrees well with the numerical dosimetry, with a very good SAR uniformity of 0.4 dB in the chamber. Furthermore, a thermal analysis and measurements were performed to provide better understanding of the temperature load and distribution in the mice during exposure.
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Affiliation(s)
- Yijian Gong
- IT'IS Foundation, ETH, Zurich, Switzerland.,Information Technology and Electrical Engineering, ETH, Zurich, Switzerland
| | | | - Thomas Tillmann
- Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, Hannover, Germany
| | - Clemens Dasenbrock
- Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, Hannover, Germany
| | - Theodoros Samaras
- Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Niels Kuster
- IT'IS Foundation, ETH, Zurich, Switzerland.,Information Technology and Electrical Engineering, ETH, Zurich, Switzerland
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Roberts M, Lightfoot E, Porter W. A New Model for the Body Size–Metabolism Relationship. Physiol Biochem Zool 2010; 83:395-405. [DOI: 10.1086/651564] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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KHOKHLOVA IRINA, DEGEN AALLAN, KRASNOV BORISR, SHENBROT GEORGYI. BODY MASS AND ENVIRONMENT: A STUDY IN NEGEV RODENTS. ACTA ACUST UNITED AC 2001. [DOI: 10.1560/b37y-lhv0-6mrr-xjw9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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12
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Gordon CJ. Normalizing the thermal effects of radiofrequency radiation: body mass versus total body surface area. Bioelectromagnetics 1987; 8:111-8. [PMID: 3619947 DOI: 10.1002/bem.2250080202] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The current guideline for exposure to radiofrequency radiation (RFR) was developed through assessment of the biological effects data collected primarily from the rat. The consensus that a lack of hazardous biological effects occurred below a whole-body-averaged specific absorption rate (SAR) of 4.0 W/kg led to the proposition of a 0.4 W/kg guideline with a built-in safety factor of 10. This paper demonstrates that if the RFR absorption rate in the rat had been normalized with respect to total body surface area rather than body mass, the exposure guideline would be 2.3 W/m2, which translates to an SAR of approximately 0.06 W/kg for an adult human. It is further shown that a given RFR absorption rate, normalized as a fraction of a species' heat loss per unit of surface area, is independent of body mass over a range of 0.03-100 kg; however, a normalization of the RFR absorption rate to heat loss per unit of body mass is highly dependent on the species' mass. Normalizing the rate of RFR absorption to the surface area of the rat indicates that the current RFR exposure guideline of 0.4 W/kg may be too high.
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13
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Conley KE. Evaporative water loss: thermoregulatory requirements and measurements in the deer mouse and white rabbit. J Comp Physiol B 1985; 155:433-6. [PMID: 3837024 DOI: 10.1007/bf00684672] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Using a physical model of the capacity for non-evaporative heat loss and measurements of metabolic heat production, I evaluated the evaporative requirements for thermoregulation in the deer mouse, Peromyscus maniculatus, and the white rabbit, Oryctolagus cuniculus. The physical limit to non-evaporative heat loss was calculated from the heat transfer properties of the two animals and expressed as a maximum thermal conductance (Cmax). Two physiologically-based thermal conductances were derived from evaporative water loss, respiratory gas exchange and core temperature measurements made between 8 and 34 degrees C on the deer mouse, and taken from published data for the white rabbit. The thermal conductance for non-evaporative heat loss (C) was calculated from net heat production, whereas Cm represented the thermal conductance required to dissipate metabolic heat production. Evaporation is required when metabolic heat production exceeds the capacity for non-evaporative heat loss (as shown by Cm greater than Cmax). However, evaporation increased in both animals although additional capacity to lose heat remained (i.e., C less than Cmax). Evaporation increased with C above 30 degrees C for the mouse and at each 5 degrees C measurement interval from 15 to 30 degrees C for the rabbit. Thus, evaporation was greater than that required for thermoregulation for both animals as determined from a physical model of heat loss because both evaporation and C increased together to regulate heat loss.
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