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Hu Y, Li S, Zhuang W, Tu H, Wan Y, Yang P. Spatial Patterned Interfacial Solar Evaporators toward Recovering Heat Loss. ACS Appl Mater Interfaces 2024; 16:10285-10294. [PMID: 38377590 DOI: 10.1021/acsami.3c19577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
The novel freshwater production technology, such as interface solar-steam conversion (ISSC) technology, has advanced so rapidly recently, where its energy capture and conversion process was localized at the air-water interface so as to achieve high efficiency of energy utilization and transformation. However, when enlarging the evaporation surface and application scale, the inevitably increased heat loss and reduced conversion efficiency put it in a dilemma: should we exploit innovative steamer constructs for practical applications. In order to effectively mitigate heat loss from the evaporator to the surrounding environment, a series of spatial pattern evaporators (SPEs) are specifically designed in this article. By recovering the energy of radiation and convection heat loss, SPEs achieved low heat loss in an open evaporator through unequal height auxiliary heat exchange platforms. In an open environment, it achieves a maximum evaporation rate of 1.68 kg m-2 h-1, with approximately 52.41% of the heat loss being reabsorbed. This sophisticated pattern design provides a promising guideline for optimizing thermal management strategies and promoting practically scalable applications.
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Affiliation(s)
- Yingfei Hu
- National Center for International Research on Photoelectric and Energy Materials, Yunnan Key Laboratory for Micro/Nano Materials & Technology, Yunnan Key Laboratory of Electromagnetic Materials and Devices, School of Materials and Energy, Yunnan University, Kunming 650091, China
| | - Simin Li
- National Center for International Research on Photoelectric and Energy Materials, Yunnan Key Laboratory for Micro/Nano Materials & Technology, Yunnan Key Laboratory of Electromagnetic Materials and Devices, School of Materials and Energy, Yunnan University, Kunming 650091, China
| | - Wenbo Zhuang
- National Center for International Research on Photoelectric and Energy Materials, Yunnan Key Laboratory for Micro/Nano Materials & Technology, Yunnan Key Laboratory of Electromagnetic Materials and Devices, School of Materials and Energy, Yunnan University, Kunming 650091, China
| | - Hongyu Tu
- National Center for International Research on Photoelectric and Energy Materials, Yunnan Key Laboratory for Micro/Nano Materials & Technology, Yunnan Key Laboratory of Electromagnetic Materials and Devices, School of Materials and Energy, Yunnan University, Kunming 650091, China
| | - Yanfen Wan
- National Center for International Research on Photoelectric and Energy Materials, Yunnan Key Laboratory for Micro/Nano Materials & Technology, Yunnan Key Laboratory of Electromagnetic Materials and Devices, School of Materials and Energy, Yunnan University, Kunming 650091, China
| | - Peng Yang
- National Center for International Research on Photoelectric and Energy Materials, Yunnan Key Laboratory for Micro/Nano Materials & Technology, Yunnan Key Laboratory of Electromagnetic Materials and Devices, School of Materials and Energy, Yunnan University, Kunming 650091, China
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Notley SR, Akerman AP, D'Souza AW, Meade RD, McCourt ER, McCormick JJ, Kenny GP. Dose-dependent nonthermal modulation of whole body heat exchange during dynamic exercise in humans. Am J Physiol Regul Integr Comp Physiol 2024; 326:R53-R65. [PMID: 37955132 DOI: 10.1152/ajpregu.00203.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 10/30/2023] [Accepted: 10/30/2023] [Indexed: 11/14/2023]
Abstract
To maintain heat balance during exercise, humans rely on skin blood flow and sweating to facilitate whole body dry and evaporative heat exchange. These responses are modulated by the rise in body temperature (thermal factors), as well as several nonthermal factors implicated in the cardiovascular response to exercise (i.e., central command, mechanoreceptors, and metaboreceptors). However, the way these nonthermal factors interact with thermal factors to maintain heat balance remains poorly understood. We therefore used direct calorimetry to quantify the effects of dose-dependent increases in the activation of these nonthermal stimuli on whole body dry and evaporative heat exchange during dynamic exercise. In a randomized crossover design, eight participants performed 45-min cycling at a fixed metabolic heat production (200 W/m2) in warm, dry conditions (30°C, 20% relative humidity) on four separate occasions, differing only in the level of lower-limb compression applied via bilateral thigh cuffs pressurized to 0, 30, 60, or 90 mmHg. This model provoked increments in nonthermal activation while ensuring the heat loss required to balance heat production was matched across trials. At end-exercise, dry heat loss was 2 W/m2 [1, 3] lower per 30-mmHg pressure increment (P = 0.006), whereas evaporative heat loss was elevated 5 W/m2 [3, 7] with each pressure increment (P < 0.001). Body heat storage and esophageal temperature did not differ across conditions (both P ≥ 0.600). Our findings indicate that the nonthermal factors engaged during exercise exert dose-dependent, opposing effects on whole body dry and evaporative heat exchange, which do not significantly alter heat balance.NEW & NOTEWORTHY To maintain heat balance during exercise, humans rely on skin blood flow and sweating to facilitate dry and evaporative heat exchange. These responses are modulated by body temperatures (thermal factors) and several nonthermal factors (e.g., central command, metaboreceptors), although the way thermal and nonthermal factors interact to regulate body temperature is poorly understood. We demonstrate that nonthermal factors exert dose-dependent, opposing effects on dry and evaporative heat loss, without altering heat storage during dynamic exercise.
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Affiliation(s)
- Sean R Notley
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Ashley P Akerman
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Andrew W D'Souza
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Robert D Meade
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Emma R McCourt
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - James J McCormick
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
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McQueen A, Barnaby R, Symonds MRE, Tattersall GJ. Birds are better at regulating heat loss through their legs than their bills: implications for body shape evolution in response to climate. Biol Lett 2023; 19:20230373. [PMID: 37990562 PMCID: PMC10663788 DOI: 10.1098/rsbl.2023.0373] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 11/01/2023] [Indexed: 11/23/2023] Open
Abstract
Endotherms use their appendages-such as legs, tails, ears and bills-for thermoregulation by controlling blood flow to near-surface blood vessels, conserving heat when it is cold, and dissipating heat in hot conditions. Larger appendages allow greater heat dissipation, and appendage sizes vary latitudinally according to Allen's rule. However, little is known about the relative importance of different appendages for thermoregulation. We investigate physiological control of heat loss via bird bills and legs using infrared thermography of wild birds. Our results demonstrate that birds are less able to regulate heat loss via their bills than their legs. In cold conditions, birds lower their leg surface temperature to below that of their plumage surface, retaining heat at their core. In warm conditions, birds increase their leg surface temperature to above that of their plumage surface, expelling heat. By contrast, bill surface temperature remains approximately 2°C warmer than the plumage surface, indicating consistent heat loss under almost all conditions. Poorer physiological control of heat loss via bird bills likely entails stronger selection for shorter bills in cold climates. This could explain why bird bills show stronger latitudinal size clines than bird legs, with implications for predicting shape-shifting responses to climate change.
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Affiliation(s)
- Alexandra McQueen
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC 3125, Australia
| | - Ryan Barnaby
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC 3125, Australia
| | - Matthew R. E. Symonds
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC 3125, Australia
| | - Glenn J. Tattersall
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, Canada L2S 3A1
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Gebremedhin KG, Fonseca VDFC, Maia ASC. Methods, Thermodynamic Applications, and Habitat Implications of Physical and Spectral Properties of Hair and Haircoats in Cattle. Animals (Basel) 2023; 13:3087. [PMID: 37835693 PMCID: PMC10571584 DOI: 10.3390/ani13193087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/17/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
The physical properties (hair diameter, hair length, haircoat depth and haircoat density) and spectral properties (absorptivity, reflectivity, transmissivity) of the hair and haircoat of cattle are inputs to heat and moisture exchange between the skin surface and the surrounding environment, and thus play a critical role in body temperature regulation. Physical and spectral properties of haircoats also play an important role in protecting the skin against penetration of ultraviolet radiation. The focus of this review is to identify accurate and consistent measurement procedures of these properties. Additionally, the paper shows the utilization of the properties on heat exchange models and their implications on voluntary thermoregulation of cattle. To highlight the effects and benefits of haircoat color vis-à-vis solar radiation and its implication on ecological habitation, a brief explanation is provided using polar bears (white haircoat in a cold environment) and black goats in a hot desert environment.
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Affiliation(s)
- Kifle G. Gebremedhin
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 2503, USA
| | - Vinicius D. F. C. Fonseca
- Animal Biometeorology Laboratory, São Paulo State University, Jaboticabal 14884-900, SP, Brazil; (V.D.F.C.F.); (A.S.C.M.)
| | - Alex S. C. Maia
- Animal Biometeorology Laboratory, São Paulo State University, Jaboticabal 14884-900, SP, Brazil; (V.D.F.C.F.); (A.S.C.M.)
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Wang Y, Zhang X, Yang X, Wang Z, Yan Y, Du B, Zhang J, Wang C. A Novel Swept-Back Fishnet-Embedded Microchannel Topology. Micromachines (Basel) 2023; 14:1705. [PMID: 37763868 PMCID: PMC10536116 DOI: 10.3390/mi14091705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/26/2023] [Accepted: 08/29/2023] [Indexed: 09/29/2023]
Abstract
High in reliability, multi in function, and strong in tracking and detecting, active phased array antennas have been widely applied in radar systems. Heat dissipation is a major technological barrier preventing the realization of next-generation high-performance phased array antennas. As a result of the advancement of miniaturization and the integration of microelectronics technology, the study and development of embedded direct cooling or heat dissipation has significantly enhanced the heat dissipation effect. In this paper, a novel swept-back fishnet-embedded microchannel topology (SBFEMCT) is designed, and various microchannel models with different fishnet runner mesh density ratios and different fishnet runner layers are established to characterize the chip Tmax, runner Pmax, and Vmax and analyze the thermal effect of SBFEMCT under these two operating conditions. The Pmax is reduced to 72.37% and 57.12% of the original at mesh density ratios of 0.5, 0.25, and 0.125, respectively. The maximum temperature reduction figures are average with little change in maximum velocity and a small increase in maximum pressure drop across the number of fishnet runner layers from 0 to 4. This paper provides a study of the latest embedded thermal dissipation from the dimension of a single chip to provide a certain degree of new ideas and references for solving the thermal technology bottleneck of next-generation high-performance phased array antennas.
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Affiliation(s)
- Yan Wang
- School of Information and Control Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xiaoyue Zhang
- School of Information and Control Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xing Yang
- School of Mechano-Electronic Engineering, Xidian University, Xi'an 710071, China
| | - Zhiji Wang
- School of Information and Control Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yuefei Yan
- Guangzhou Institute of Technology, Xidian University, Guangzhou 510555, China
| | - Biao Du
- CETC No.54 Research Institute, Shijiazhuang 050081, China
| | - Jiliang Zhang
- CETC No.54 Research Institute, Shijiazhuang 050081, China
| | - Congsi Wang
- Guangzhou Institute of Technology, Xidian University, Guangzhou 510555, China
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De Toni L, Finocchi F, Jawich K, Ferlin A. Global warming and testis function: A challenging crosstalk in an equally challenging environmental scenario. Front Cell Dev Biol 2023; 10:1104326. [PMID: 36726592 PMCID: PMC9885165 DOI: 10.3389/fcell.2022.1104326] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 12/29/2022] [Indexed: 01/18/2023] Open
Abstract
Environmental pollution, accounting for both chemical and physical factors, is a major matter of concern due to its health consequences in both humans and animals. The release of greenhouse gases with the consequent increase in environmental temperature is acknowledged to have a major impact on the health of both animals and humans, in current and future generations. A large amount of evidence reports detrimental effects of acute heat stress on testis function, particularly on the spermatogenetic and steroidogenetic process, in both animal and human models, wich is largely related to the testis placement within the scrotal sac and outside the abdomen, warranting an overall scrotal temperature of 2°C-4°C lower than the core body temperature. This review will provide a thorough evaluation of environmental temperature's effect on testicular function. In particular, basic concepts of body thermoregulation will be discussed together with available data about the association between testis damage and heat stress exposure. In addition, the possible association between global warming and the secular decline of testis function will be critically evaluated in light of the available epidemiological studies.
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Affiliation(s)
- Luca De Toni
- Department of Medicine, Unit of Andrology and Reproductive Medicine, University of Padova, Padova, Italy,*Correspondence: Luca De Toni,
| | - Federica Finocchi
- Department of Medicine, Unit of Andrology and Reproductive Medicine, University of Padova, Padova, Italy
| | - Kenda Jawich
- Department of Biochemistry and Microbiology, Faculty of Pharmacy, Damascus University, Damascus, Syria,Department of Biochemistry, International University for Science and Technology, Daraa, Syria
| | - Alberto Ferlin
- Department of Medicine, Unit of Andrology and Reproductive Medicine, University of Padova, Padova, Italy
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Kondratiev VV, Sysoev IA, Kolosov AD, Galishnikova VV, Gladkikh VA, Karlina AI, Karlina YI. Development and Testing of the Thermoelectric Thermal Energy Conversion Device in the Conditions of Existing Aluminum Production. Materials (Basel) 2022; 15:8526. [PMID: 36500021 PMCID: PMC9736986 DOI: 10.3390/ma15238526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/11/2022] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
The aim of the work is to develop an energy-saving device that provides the conversion of thermal energy into electrical energy. The design and materials of the thermoelectric converter unit, consisting of 12 thermoelectric converter modules, a cooling radiator and a switching unit, were developed and selected. Based on the test results, the zone of the maximum temperatures in the section of the gas duct recommended for the installation of a gas cooling module using a thermoelectric converter was determined. The technology for cooling gases with the help of a thermoelectric converter was tested on the site located in front of the experimental heat exchanger. An assessment of the efficiency of the conversion of heat into electrical energy was conducted using the design of the thermoelectric converter unit, based on thermoelectric modules TGM 127-1.4-1.2. It was determined that the device is capable of generating electricity stably for production needs. The data obtained showed that, at a temperature difference of 75-80 °C between the wall surface of the gas duct section and the coolant, the power of one thermoelectric converter block of the gas cooling system reaches 9 W.
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Affiliation(s)
- Viktor V. Kondratiev
- Laboratory of Geochemistry of Ore Formation and Geochemical Methods of Prospecting, A. P. Vinogradov Institute of Geochemistry of the Siberian Branch of the Russian Academy of Sciences, 664033 Irkutsk, Russia
| | - Ivan A. Sysoev
- LLC Scientific Research Center of Energy-Resource-Saving Technologies, 664074 Irkutsk, Russia
| | | | - Vera V. Galishnikova
- Stroytest Research and Testing Center, Moscow State University of Civil Engineering, 26, Yaroslavskoye Shosse, 129337 Moscow, Russia
| | - Vitaliy A. Gladkikh
- Stroytest Research and Testing Center, Moscow State University of Civil Engineering, 26, Yaroslavskoye Shosse, 129337 Moscow, Russia
| | - Antonina I. Karlina
- Stroytest Research and Testing Center, Moscow State University of Civil Engineering, 26, Yaroslavskoye Shosse, 129337 Moscow, Russia
| | - Yuliya I. Karlina
- Stroytest Research and Testing Center, Moscow State University of Civil Engineering, 26, Yaroslavskoye Shosse, 129337 Moscow, Russia
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Wood T, Johnson M, Temples T, Bordelon C. Thermoneutral Environment for Neonates: Back to the Basics. Neonatal Netw 2022; 41:289-296. [PMID: 36002281 DOI: 10.1891/nn-2022-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2022] [Indexed: 11/25/2022]
Abstract
Thermoregulation is an essential component to the stability and long-term outcomes of newborns and critically-ill neonates. A thermoneutral environment (TNE) is an environment in which a neonate maintains a normal body temperature while minimizing energy expenditure and oxygen consumption. Neonates who experience thermal stability within a TNE demonstrate enhanced growth, decreased respiratory support, decreased oxygen requirements, increased glucose stability, reduced mortality, and reduced morbidities associated with hyperthermia and hypothermia. Heat exchange occurs between the neonate and surrounding environment through four mechanisms: evaporation, conduction, convection, and radiation. By recognizing the methods by which heat is lost or gained, the neonatal provider can prevent adverse conditions related to abnormal thermal control and support a thermoneutral neonatal environment.
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Kosiński S, Podsiadło P, Darocha T, Pasquier M, Mendrala K, Sanak T, Zafren K. Prehospital Use of Ultrathin Reflective Foils. Wilderness Environ Med 2022; 33:134-139. [PMID: 34998706 DOI: 10.1016/j.wem.2021.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 10/20/2021] [Accepted: 11/15/2021] [Indexed: 11/19/2022]
Abstract
Ultrathin reflective foils (URFs) are widely used to protect patients from heat loss, but there is no clear evidence that they are effective. We review the physics of thermal insulation by URFs and discuss their clinical applications. A conventional view is that the high reflectivity of the metallic side of the URF is responsible for thermal protection. In most circumstances, the heat radiated from a well-clothed body is minimal and the reflecting properties of a URF are relatively insignificant. The reflection of radiant heat can be impaired by condensation and freezing of the moisture on the inner surface and by a tight fit of the URF against the outermost layer of insulation. The protection by thermal insulating materials depends mostly on the ability to trap air and increases with the number of covering layers. A URF as a single layer may be useful in low wind conditions and moderate ambient temperature, but in cold and windy conditions a URF probably best serves as a waterproof outer covering. When a URF is used to protect against hypothermia in a wilderness emergency, it does not matter whether the gold or silver side is facing outward.
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Affiliation(s)
- Sylweriusz Kosiński
- Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Paweł Podsiadło
- Institute of Medical Sciences, Jan Kochanowski University Medical College, Kielce, Poland
| | - Tomasz Darocha
- Department of Anaesthesiology and Intensive Care, Medical University of Silesia, Katowice, Poland
| | - Mathieu Pasquier
- Emergency Department, Lausanne University Hospital, Lausanne, Switzerland
| | - Konrad Mendrala
- Department of Anaesthesiology and Intensive Care, Medical University of Silesia, Katowice, Poland
| | - Tomasz Sanak
- Center for Innovative Medical Education, Jagiellonian University Medical College, Krakow, Poland
| | - Ken Zafren
- Department of Emergency Medicine Stanford University Medical Center, Stanford, California Department of Emergency Medicine, Alaska Native Medical Center, Anchorage, Alaska.
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Grinham J, Hancock MJ, Kumar K, Bechthold M, Ingber DE, Aizenberg J. Bioinspired design and optimization for thin film wearable and building cooling systems. Bioinspir Biomim 2021; 17:015003. [PMID: 34644686 DOI: 10.1088/1748-3190/ac2f55] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 10/13/2021] [Indexed: 06/13/2023]
Abstract
In this work, we report a paradigmatic shift in bioinspired microchannel heat exchanger design toward its integration into thin film wearable devices, thermally active surfaces in buildings, photovoltaic devices, and other thermoregulating devices whose typical cooling fluxes are below 1 kW m-2. The transparent thermoregulation device is fabricated by bonding a thin corrugated elastomeric film to the surface of a substrate to form a microchannel water-circuit with bioinspired unit cell geometry. Inspired by the dynamic scaling of flow systems in nature, we introduce empirically derived sizing rules and a novel numerical optimization method to maximize the thermoregulation performance of the microchannel network by enhancing the uniformity of flow distribution. The optimized network design results in a 25% to 37% increase in the heat flux compared to non-optimized designs. The study demonstrates the versatility of the presented design and architecture by fabricating and testing a scaled-up numerically optimized heat exchanger device for building-scale and wearable applications.
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Affiliation(s)
- Jonathan Grinham
- Harvard Graduate School of Design, United States of America
- Harvard Center for Green Buildings and Cities, United States of America
- Wyss Institute for Biologically Inspired Engineering, Harvard University, United States of America
| | | | - Kitty Kumar
- Wyss Institute for Biologically Inspired Engineering, Harvard University, United States of America
| | - Martin Bechthold
- Harvard Graduate School of Design, United States of America
- Harvard Center for Green Buildings and Cities, United States of America
- Wyss Institute for Biologically Inspired Engineering, Harvard University, United States of America
| | - Donald E Ingber
- Wyss Institute for Biologically Inspired Engineering, Harvard University, United States of America
- Vascular Biology Program and Department of Surgery, Boston Children's Hospital and Harvard Medical School, United States of America
- Harvard John A Paulson School of Engineering and Applied Sciences, United States of America
| | - Joanna Aizenberg
- Wyss Institute for Biologically Inspired Engineering, Harvard University, United States of America
- Harvard John A Paulson School of Engineering and Applied Sciences, United States of America
- Department of Chemistry and Chemical Biology, Harvard University, United States of America
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11
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Pinel I, Biškauskaitė R, Pal'ová E, Vrouwenvelder H, van Loosdrecht M. Assessment of the Impact of Temperature on Biofilm Composition with a Laboratory Heat Exchanger Module. Microorganisms 2021; 9:1185. [PMID: 34072656 DOI: 10.3390/microorganisms9061185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/24/2021] [Accepted: 05/26/2021] [Indexed: 11/17/2022] Open
Abstract
Temperature change over the length of heat exchangers might be an important factor affecting biofouling. This research aimed at assessing the impact of temperature on biofilm accumulation and composition with respect to bacterial community and extracellular polymeric substances. Two identical laboratory-scale plate heat exchanger modules were developed and tested. Tap water supplemented with nutrients was fed to the two modules to enhance biofilm formation. One “reference” module was kept at 20.0 ± 1.4 °C and one “heated” module was operated with a counter-flow hot water stream resulting in a bulk water gradient from 20 to 27 °C. Biofilms were grown during 40 days, sampled, and characterized using 16S rRNA gene amplicon sequencing, EPS extraction, FTIR, protein and polysaccharide quantifications. The experiments were performed in consecutive triplicate. Monitoring of heat transfer resistance in the heated module displayed a replicable biofilm growth profile. The module was shown suitable to study the impact of temperature on biofouling formation. Biofilm analyses revealed: (i) comparable amounts of biofilms and EPS yield in the reference and heated modules, (ii) a significantly different protein to polysaccharide ratio in the EPS of the reference (5.4 ± 1.0%) and heated modules (7.8 ± 2.1%), caused by a relatively lower extracellular sugar production at elevated temperatures, and (iii) a strong shift in bacterial community composition with increasing temperature. The outcomes of the study, therefore, suggest that heat induces a change in biofilm bacterial community members and EPS composition, which should be taken into consideration when investigating heat exchanger biofouling and cleaning strategies. Research potential and optimization of the heat exchanger modules are discussed.
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Gardner JL, Amano T, Peters A, Sutherland WJ, Mackey B, Joseph L, Stein J, Ikin K, Little R, Smith J, Symonds MRE. Australian songbird body size tracks climate variation: 82 species over 50 years. Proc Biol Sci 2019; 286:20192258. [PMID: 31771472 DOI: 10.1098/rspb.2019.2258] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The observed variation in the body size responses of endotherms to climate change may be explained by two hypotheses: the size increases with climate variability (the starvation resistance hypothesis) and the size shrinks as mean temperatures rise (the heat exchange hypothesis). Across 82 Australian passerine species over 50 years, shrinking was associated with annual mean temperature rise exceeding 0.012°C driven by rising winter temperatures for arid and temperate zone species. We propose the warming winters hypothesis to explain this response. However, where average summer temperatures exceeded 34°C, species experiencing annual rise over 0.0116°C tended towards increasing size. Results suggest a broad-scale physiological response to changing climate, with size trends probably reflecting the relative strength of selection pressures across a climatic regime. Critically, a given amount of temperature change will have varying effects on phenotype depending on the season in which it occurs, masking the generality of size patterns associated with temperature change. Rather than phenotypic plasticity, and assuming body size is heritable, results suggest selective loss or gain of particular phenotypes could generate evolutionary change but may be difficult to detect with current warming rates.
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Affiliation(s)
- Janet L Gardner
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.,School of Biological Sciences, Monash University, Clayton, Victoria 3168, Australia
| | - Tatsuya Amano
- School of Biological Sciences, University of Queensland, Brisbane, 4072 Queensland, Australia
| | - Anne Peters
- School of Biological Sciences, Monash University, Clayton, Victoria 3168, Australia
| | - William J Sutherland
- Department of Zoology, University of Cambridge, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK
| | - Brendan Mackey
- Griffith Climate Change Response Program, Griffith University, Gold Coast Campus, Queensland 4222, Australia
| | - Leo Joseph
- Australian National Wildlife Collection, CSIRO National Research Collections Australia, GPO Box 1700, Canberra, Australian Capital Territory 2601, Australia
| | - John Stein
- The Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Karen Ikin
- The Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Roellen Little
- School of Biological Sciences, Monash University, Clayton, Victoria 3168, Australia
| | - Jesse Smith
- School of Biological Sciences, Monash University, Clayton, Victoria 3168, 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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13
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Rupp AIKS, Gruber P. Biomimetic Groundwork for Thermal Exchange Structures Inspired by Plant Leaf Design. Biomimetics (Basel) 2019; 4:E75. [PMID: 31783650 PMCID: PMC6963917 DOI: 10.3390/biomimetics4040075] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 11/13/2019] [Accepted: 11/20/2019] [Indexed: 01/19/2023] Open
Abstract
Geometry is a determining factor for thermal performance in both biological and technical systems. While biology has inspired thermal design before, biomimetic translation of leaf morphology into structural aspects of heat exchangers remains largely unaddressed. One determinant of plant thermal endurance against environmental exposure is leaf shape, which modulates the leaf boundary layer, transpiration, evaporative cooling, and convective exchange. Here, we lay the research groundwork for the extraction of design principles from leaf shape relations to heat and mass transfer. Leaf role models were identified from an extensive literature review on environmentally sensitive morphology patterns and shape-dependent exchange. Addressing canopy sun-shade dimorphism, sun leaves collected from multiple oak species exceeded significantly in margin extension and shape dissection. Abstracted geometries (i.e., elongated; with finely toothed edges; with few large-scale teeth) were explored with paper models of the same surface area in a controlled environment of minimal airflow, which is more likely to induce leaf thermal stress. For two model characteristic dimensions, evaporation rates were significantly faster for the dissected geometries. Shape-driven transfer enhancements were higher for the smaller models, and finely toothed edges reached local cooling up to 10 °C below air temperature. This investigation breaks new ground for solution-based biomimetics to inform the design of evaporation-assisted and passively enhanced thermal systems.
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Affiliation(s)
- Ariana I. K. S. Rupp
- Department of Biology, Biomimicry Research and Innovation Center, The University of Akron, Akron, OH 44325, USA
| | - Petra Gruber
- Myers School of Art and Department of Biology, Biomimicry Research and Innovation Center, The University of Akron, Akron, OH 44325, USA;
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14
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D'Souza AW, Notley SR, Brown EK, Poirier MP, Kenny GP. The Hexoskin physiological monitoring shirt does not impair whole-body heat loss during exercise in hot-dry conditions. Appl Physiol Nutr Metab 2018; 44:332-335. [PMID: 30336069 DOI: 10.1139/apnm-2018-0370] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Using direct calorimetry, we determined if the Hexoskin shirt (Carré Technologies Inc., Que., Canada), a wearable device for monitoring physiological strain, would compromise whole-body heat loss and exacerbate body heat storage during moderate-intensity activity in hot-dry conditions. The shirt did not impair heat dissipation and resulted in similar body heat storage when worn alone relative to a semi-nude condition (214 vs. 211 kJ) or when worn underneath a work uniform compared with a cotton undershirt (307 vs. 318 kJ).
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Affiliation(s)
- Andrew W D'Souza
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada.,Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Sean R Notley
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada.,Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Erin K Brown
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada.,Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Martin P Poirier
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada.,Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada
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15
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Latorre-Pérez A, Vilanova C, Alcaina JJ, Porcar M. Thermoelectric heat exchange and growth regulation in a continuous yeast culture. Microbiologyopen 2018; 8:e00648. [PMID: 29797790 PMCID: PMC6436441 DOI: 10.1002/mbo3.648] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/23/2018] [Accepted: 04/07/2018] [Indexed: 12/01/2022] Open
Abstract
We have designed a thermoelectric heat exchanger (TEHE) for microbial fermentations that is able to produce electric power from a microbial continuous culture using the intrinsic heat generated by microbial growth. While the TEHE was connected, the system proved able to stably self‐maintain both the temperature and the optical density of the culture. This paves the way toward a more sustainable operation of microbial fermentations, in which energy could be saved by converting part of the metabolic heat into usable electric power.
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Affiliation(s)
| | | | - José J Alcaina
- Biotechnology and Synthetic Biology Laboratory, I2SysBio (Institute for Integrative Systems Biology), University of Valencia-CSIC, Paterna, Spain
| | - Manuel Porcar
- Darwin Bioprospecting Excellence SL, Paterna, Spain.,Biotechnology and Synthetic Biology Laboratory, I2SysBio (Institute for Integrative Systems Biology), University of Valencia-CSIC, Paterna, Spain
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16
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Imre AR, Wojciechowski KW, Györke G, Groniewsky A, Narojczyk JW. Pressure-Volume Work for Metastable Liquid and Solid at Zero Pressure. Entropy (Basel) 2018; 20:e20050338. [PMID: 33265428 PMCID: PMC7512857 DOI: 10.3390/e20050338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 03/14/2018] [Accepted: 04/20/2018] [Indexed: 11/16/2022]
Abstract
Unlike with gases, for liquids and solids the pressure of a system can be not only positive, but also negative, or even zero. Upon isobaric heat exchange (heating or cooling) at p = 0, the volume work (p-V) should be zero, assuming the general validity of traditional δW = dWp = −pdV equality. This means that at zero pressure, a special process can be realized; a macroscopic change of volume achieved by isobaric heating/cooling without any work done by the system on its surroundings or by the surroundings on the system. A neologism is proposed for these dWp = 0 (and in general, also for non-trivial δW = 0 and W = 0) processes: “aergiatic” (from Greek: Ἀεργία, “inactivity”). In this way, two phenomenologically similar processes—adiabatic without any heat exchange, and aergiatic without any work—would have matching, but well-distinguishable terms.
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Affiliation(s)
- Attila R. Imre
- Thermohydraulics Department, MTA Centre for Energy Research, P.O. Box 49, 1525 Budapest, Hungary
- Budapest University of Technology and Economics, Department of Energy Engineering, Muegyetem rkp. 3, H-1111 Budapest, Hungary
- Correspondence: or
| | - Krzysztof W. Wojciechowski
- Institute of Molecular Physics, Polish Academy of Sciences, ul. M. Smoluchowskiego 17, PL-60-179 Poznan, Poland
- President Stanisław Wojciechowski State University of Applied Sciences, Nowy Swiat 4, 62-800 Kalisz, Poland
| | - Gábor Györke
- Budapest University of Technology and Economics, Department of Energy Engineering, Muegyetem rkp. 3, H-1111 Budapest, Hungary
| | - Axel Groniewsky
- Budapest University of Technology and Economics, Department of Energy Engineering, Muegyetem rkp. 3, H-1111 Budapest, Hungary
| | - Jakub. W. Narojczyk
- Institute of Molecular Physics, Polish Academy of Sciences, ul. M. Smoluchowskiego 17, PL-60-179 Poznan, Poland
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17
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Notley SR, Park J, Tagami K, Ohnishi N, Taylor NAS. Variations in body morphology explain sex differences in thermoeffector function during compensable heat stress. Exp Physiol 2017; 102:545-562. [PMID: 28231604 DOI: 10.1113/ep086112] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/08/2017] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Can sex-related differences in cutaneous vascular and sudomotor responses be explained primarily by variations in the ratio between body surface area and mass during compensable exercise that elicits equivalent heat-loss requirements and mean body temperature changes across participants? What is the main finding and its importance? Mass-specific surface area was a significant determinant of vasomotor and sudomotor responses in men and women, explaining 10-48% of the individual thermoeffector variance. Nonetheless, after accounting for changes in mean body temperature and morphological differences, sex explained only 5% of that inter-individual variability. It was concluded that sex differences in thermoeffector function are morphologically dependent, but not sex dependent. Sex is sometimes thought to be an independent modulator of cutaneous vasomotor and sudomotor function during heat exposure. Nevertheless, it was hypothesized that, when assessed during compensable exercise that evoked equal heat-loss requirements across participants, sex differences in those thermoeffectors would be explained by variations in the ratio between body surface area and mass (specific surface area). To evaluate that possibility, vasomotor and sudomotor functions were assessed in 60 individuals (36 men and 24 women) with widely varying (overlapping) specific surface areas (range, 232.3-292.7 and 241.2-303.1 cm2 kg-1 , respectively). Subjects completed two trials in compensable conditions (28°C, 36% relative humidity) involving rest (20 min) and steady-state cycling (45 min) at fixed, area-specific metabolic heat-production rates (light, ∼135 W m-2 ; moderate, ∼200 W m-2 ). Equivalent heat-loss requirements and mean body temperature changes were evoked across participants. Forearm blood flow and vascular conductance were positively related to specific surface area during light work in men (r = 0.67 and r = 0.66, respectively; both P < 0.05) and during both exercise intensities in women (light, r = 0.57 and r = 0.69; and moderate, r = 0.64 and r = 0.68; all P < 0.05). Whole-body and local sweat rates were negatively related to that ratio (correlation coefficient range, -0.33 to -0.62; all P < 0.05) during both work rates in men and women. Those relationships accounted for 10-48% of inter-individual thermoeffector variance (P < 0.05). Furthermore, after accounting for morphological differences, sex explained no more than 5% of that variability (P < 0.05). It was concluded that, when assessed during compensable exercise, sex differences in thermoeffector function were largely determined morphologically, rather than being sex dependent.
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Affiliation(s)
- Sean R Notley
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Joonhee Park
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Kyoko Tagami
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Norikazu Ohnishi
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, NSW, 2522, Australia.,Faculty of Nursing, Mie Prefectural College of Nursing, Mie, 514-0116, Japan
| | - Nigel A S Taylor
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, NSW, 2522, Australia
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18
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Davenport J, Jones TT, Work TM, Balazs GH. Topsy-turvy: turning the counter-current heat exchange of leatherback turtles upside down. Biol Lett 2016; 11:rsbl.2015.0592. [PMID: 26445982 DOI: 10.1098/rsbl.2015.0592] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Counter-current heat exchangers associated with appendages of endotherms feature bundles of closely applied arteriovenous vessels. The accepted paradigm is that heat from warm arterial blood travelling into the appendage crosses into cool venous blood returning to the body. High core temperature is maintained, but the appendage functions at low temperature. Leatherback turtles have elevated core temperatures in cold seawater and arteriovenous plexuses at the roots of all four limbs. We demonstrate that plexuses of the hindlimbs are situated wholly within the hip musculature, and that, at the distal ends of the plexuses, most blood vessels supply or drain the hip muscles, with little distal vascular supply to, or drainage from the limb blades. Venous blood entering a plexus will therefore be drained from active locomotory muscles that are overlaid by thick blubber when the adults are foraging in cold temperate waters. Plexuses maintain high limb muscle temperature and avoid excessive loss of heat to the core, the reverse of the accepted paradigm. Plexuses protect the core from overheating generated by muscular thermogenesis during nesting.
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Affiliation(s)
- John Davenport
- School of Biological, Earth and Environmental Sciences, University College Cork, North Mall Campus, Distillery Fields, Cork, Ireland
| | - T Todd Jones
- NOAA Fisheries, Pacific Islands Fisheries Science Center, 1845 Wasp Boulevard, Building 176, Honolulu, HI 96818, USA
| | - Thierry M Work
- US Geological Survey, National Wildlife Health Center, Honolulu Field Station, Honolulu, HI 96850, USA
| | - George H Balazs
- NOAA Fisheries, Pacific Islands Fisheries Science Center, 1845 Wasp Boulevard, Building 176, Honolulu, HI 96818, USA
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19
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Notley SR, Park J, Tagami K, Ohnishi N, Taylor NAS. Morphological dependency of cutaneous blood flow and sweating during compensable heat stress when heat-loss requirements are matched across participants. J Appl Physiol (1985) 2016; 121:25-35. [PMID: 27125845 DOI: 10.1152/japplphysiol.00151.2016] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/26/2016] [Indexed: 11/22/2022] Open
Abstract
Human heat loss is thought, in part, to be morphologically related. It was therefore hypothesized that when heat-loss requirements and body temperatures were matched, that the mass-specific surface area alone could significantly explain both cutaneous vascular and sudomotor responses during compensable exercise. These thermoeffector responses were examined in 36 men with widely varying mass-specific surface areas (range, 232.3-292.7 cm(2)/kg), but of similar age, aerobic fitness, and adiposity. Subjects completed two trials under compensable conditions (28.1°C, 36.8% relative humidity), each involving rest (20 min) and steady-state cycling (45 min) at two matched metabolic heat-production rates (light, ∼135 W/m(2); moderate, ∼200 W/m(2)). Following equivalent mean body temperature changes, forearm blood flow and vascular conductance (r = 0.63 and r = 0.65) shared significant, positive associations with the mass-specific surface area during light work (P < 0.05), explaining ∼45% of the vasomotor variation. Conversely, during light and moderate work, whole body sweat rate, as well as local sweat rate and sudomotor sensitivity at three of four measured sites, revealed moderate, negative relationships with the mass-specific surface area (correlation coefficient range -0.37 to -0.73, P < 0.05). Moreover, those relationships could uniquely account for between 10 and 53% of those sweating responses (P < 0.05). Therefore, both thermoeffector responses displayed a significant morphological dependency in the presence of equivalent thermoafferent drive. Indeed, up to half of the interindividual variation in these effector responses could now be explained through morphological differences and the first principles governing heat transfer.
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Affiliation(s)
- Sean R Notley
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, New South Wales, Australia; and
| | - Joonhee Park
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, New South Wales, Australia; and
| | - Kyoko Tagami
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, New South Wales, Australia; and
| | - Norikazu Ohnishi
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, New South Wales, Australia; and Faculty of Nursing, Mie Prefectural College of Nursing, Mie, Japan
| | - Nigel A S Taylor
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, New South Wales, Australia; and
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20
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Deptula J, Valleley M, Glogowski K, Detwiler J, Hammel J, Duncan K. Clinical evaluation of the Terumo Capiox FX05 hollow fiber oxygenator with integrated arterial line filter. J Extra Corpor Technol 2009; 41:220-5. [PMID: 20092076 PMCID: PMC4813544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Accepted: 09/01/2009] [Indexed: 05/28/2023]
Abstract
Perfusion techniques and equipment in pediatric open heart surgery have continued to focus on decreasing prime volumes and lowering surface areas of the cardiopulmonary bypass circuit. While this has improved drastically over the last 20 years, greater demand is being placed on the perfusionist to reduce the deleterious effects of bypass without compromising safety or efficiency. Specifically, manufacturers of disposable perfusion equipment have focused on providing pediatric perfusionists with oxygenators that provide the smallest prime and surface area possible while attempting to maximize performance. Recently,Terumo Cardiovascular has introduced the Capiox FX05, a neonatal hollow fiber oxygenator that includes an integrated arterial line filter. The FX05 provides a blood flow range of 0.1-1.5 L/min and a low priming volume of 43 mL. Additionally, it is coated with X Coating, a biocompatible, hydrophilic polymer surface coating that reduces platelet adhesion and protein denaturation. The purpose of this study was to test the FX05 for gas transfer, blood path resistance, and blood handling characteristics in a standardized clinical setting. Heat exchange coefficients were also calculated during the cooling and warming period. Other data analyzed includes bypass circuit prime volumes and initial patient hematocrit along with the total operative homologous blood donor exposures. In summary, the FX05 offers good gas exchange capabilities and a low pressure drop during normal cardiopulmonary bypass parameters along with the safety of an integrated arterial line filter. Furthermore, the FX05 with integrated filter allows a reduction in overall bypass prime volume and surface area while promoting the reduction of homologous blood transfusions, optimizing hemostasis.
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Affiliation(s)
- Joseph Deptula
- Department of Cardiothoracic and Vascular Surgery, Children's Hospital and Medical Center, Omaha, Nebraska, USA.
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