Objective: Resting energy expenditure (EE) is a major contributor to the total EE and thus plays an important role in body weight regulation. Adaptive thermogenesis is a major component of EE in rodents, but little is known on the effects of exposure of humans to mild and sustainable reduction in environmental temperature.
Design: To characterize the dynamic changes in continuously measured resting EE, substrate utilization, and hormonal axes simultaneously in response to mild reduction in environmental temperature, we performed a cross-over intervention.
Methods: Twenty-five volunteers underwent two 12-h recordings of EE in whole room indirect calorimeters at 24 and 19 °C with simultaneous measurement of spontaneous movements and hormonal axes.
Results: Exposure to 19 °C resulted in an increase in plasma and urine norepinephrine levels (P<0.0001), and a 5.96% (P<0.001) increase in EE without significant changes in spontaneous physical activity. Exposure to the lower temperature resulted in a significant increase in free fatty acid levels (P<0.01), fasting insulin levels (P<0.05), and a marginal decrease in postprandial glucose levels. A small but significant (P<0.002) increase in serum free thyroxine and urinary free cortisol (P<0.05) was observed at 19 °C.
Conclusions: Our observations indicate that exposure to 19 °C, a mild and tolerable cold temperature, results in a predictable increase in EE driven by a sustained rise in catecholamine and the activation of counter-regulatory mechanisms.
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http://dx.doi.org/10.1530/EJE-10-0627 | DOI Listing |
J Plant Physiol
January 2025
Department of Ecology, Faculty of Sciences, University of Málaga, Málaga, Spain.
Cold-temperate and Arctic hard bottom coastal ecosystems are dominated by kelp forests, which have a high biomass production and provide important ecosystem services, but are subject to change due to ocean warming. However, the photophysiological response to increasing temperature of ecologically relevant species, such as Laminaria digitata, might depend on the local thermal environment where the population has developed. Therefore, the effects of temperature on growth rate, biochemical composition, maximum quantum yield, photosynthetic quotient and carbon budget of young cultured sporophytes of Laminaria digitata from the Arctic at Spitsbergen (SPT; cultured at 4, 10 and 16 °C) and from the cold-temperate North Sea island of Helgoland (HLG; cultured at 10, 16 and 22 °C) were comparatively analyzed.
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January 2025
Environment Research Institute, Shandong University, Qingdao 266237, China.
Globally, drug-impaired driving fatalities now exceed those from drunk driving, urging the need for on-site and roadside detection methods. In this study, a photothermal desorption and reagent-assisted low-temperature plasma ionization miniature ion trap mass spectrometer (PDRA-LTP-ITMS) was developed for on-site detection of drug-impaired driving. The pseudomultiple reaction monitoring (MRM) in PDRA-LTP-ITMS enables continuous ion selection during ion introduction and improved sensitivity to nearly 3-fold compared with the conventional full scan mode.
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January 2025
Human and Environmental Physiology Research Unit, School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada.
With mines extending deeper and rising surface temperatures, workers are exposed to hotter environments. This study aimed to characterize heat stress and strain in the Canadian mining industry and evaluate the utility of the Heat Strain Score Index (HSSI), combined with additional self-reported adverse health outcomes. An exploratory web-based survey was conducted among workers ( = 119) in the Canadian mining industry.
View Article and Find Full Text PDFActa Bioeng Biomech
June 2024
4Department of Pediatric Dentistry and Preclinical Dentistry, Wroclaw Medical University, Wrocław, Poland.
: Caries or iatrogenic thermal trauma of the teeth have a significant impact on the dental pulp structure connected with stimulation of angiogenesis and lymphangiogenesis. Therefore, the aim of the study was to identify the difference in the rate of heat dissipation by vessels present in the dental pulp. : Freshly extracted healthy ( = 10) and carious ( = 14) molars and premolars were cut on a diamond saw and subjected to active thermographic examination and then subjected to lymphoscintigraphy and X-ray examination.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
School of Energy and Environment, Southeast University, Nanjing 210096, China.
The broad temperature adaptability associated with the desolvation process remains a formidable challenge for organic electrolytes in rechargeable metal batteries, especially under low-temperature (LT) conditions. Although a traditional approach involves utilizing electrolytes with a high degree of anion participation in the solvation structure, known as weakly solvation electrolytes (WSEs), the solvation structure of these electrolytes is highly susceptible to temperature fluctuations, potentially undermining their LT performance. To address this limitation, we have devised an innovative electrolyte that harnesses the interplay between solvent molecules, effectively blending strong and weak solvents while incorporating anion participation in a solvation structure that remains mostly unchanged by temperature variations.
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