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Critical thermal maximum (CT ) is widely used to measure upper thermal tolerance in fish but is rarely examined in embryos. Upper thermal limits generally depend on an individual's thermal history, which molds plasticity. We examined how thermal acclimation affects thermal tolerance of brook trout (Salvelinus fontinalis) embryos using a novel method to assess CT in embryos incubated under three thermal regimes. Warm acclimation was associated with an increase in embryonic upper thermal tolerance. However, CT variability was markedly higher than is typical for juvenile or adult salmonids.
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http://dx.doi.org/10.1111/jfb.15624 | DOI Listing |
ACS Omega
September 2025
Materials and Manufacturing Directorate, AFRL/RXEE, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433, United States.
This study addresses a critical limitation in direct bonded copper (DBC) materials used in power electronics by introducing a copper-zirconium (Cu/Zr) alloy interposing layer at the copper-ceramic interface. This novel design aims to mitigate mechanical stress induced by mismatched material properties, such as the coefficient of thermal expansion (CTE) and elastic modulus, during thermal cycling. The key findings of this study are (1) thermal fatigue improvement: Test samples with the Cu/Zr interface layer (Cu-Cu/Zr-AlN) three times enhanced thermal fatigue resistance, surviving 30 thermal cycles from -55 to 300 °C before delamination, while standard DBC substrates without the Cu/Zr layer failed after just 10 cycles, indicating a performance improvement with the Cu/Zr alloy, (2) durability projections: Based on the Coffin-Manson model, if the upper temperature is capped at 150 °C, the Cu-Cu/Zr-AlN substrates are projected to survive approximately 1372 cycles, underscoring their potential for long-term reliability, and (3) stress mitigation: The Cu/Zr alloy layer bridges the CTE disparity between copper and ceramic, reducing mechanical stress and improving structural integrity across a broad temperature range (-55 to 300 °C).
View Article and Find Full Text PDFJ Biomol Struct Dyn
September 2025
Enzyme and Microbial Technology Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.
A thermostable paraoxonase (S3wahi-PON) from sp. strain S3wahi was recently characterised and shown to possess stability across a broad temperature range. This study expands upon the initial biochemical characterisation of S3wahi-PON by investigating the structural determinants and conformational adaptability that contribute to its thermostability, using an integrated approach that combines biophysical techniques and molecular dynamics (MD) simulations across a temperature range of 10 °C to 90 °C.
View Article and Find Full Text PDFJ Therm Biol
September 2025
Instituto de Física de São Carlos, Universidade de São Paulo,São Carlos, 13560-970, São Paulo, Brazil.
The world is warming rapidly, threatening the extinction of much of the world's biota. Thermal tolerance plasticity has been touted as an important buffer against global warming. The temperature tolerance-plasticity trade-off hypothesis (TOH) posits that ectotherms who have adapted to high temperatures have done so at the expense of having limited plasticity to further improve their heat tolerance.
View Article and Find Full Text PDFJ Phys Condens Matter
September 2025
Physics and Astronomy, UVic, 3800 Finnerty Road, Victoria, British Columbia, V8P 5C2, CANADA.
We report measurements of the normal-state and superconducting properties of thin-film NbTiN usingLi-detected nuclear magnetic resonance (-NMR). In these experiments, radioactiveLiprobes were implanted 21 nm below the surface of a NbTiN(91 nm) film in NbTiN/(91 nm)/AlN(4 nm)/Nb and its NMR response recorded (viaLi's-emissions) between 4.6 K and and 270 K in a 4.
View Article and Find Full Text PDFEur J Appl Physiol
September 2025
Laboratório de Biomecânica, Centro de Desportos, Universidade Federal de Santa Catarina, Florianópolis, Brazil.
Purpose: The environmental conditions in open water swimming (OWS) can impair thermoregulation. Here we explored and discussed four interrelated topics concerning the disruption of thermal homeostasis, in parallel with the underlying physiological mechanisms, during OWS competitions in hot climates: (i) potential health risks; (ii) possible impacts on performance; (iii) technical feasibility of core temperature (Tc) measurement; and (iv) cooling strategies applicable to this context.
Methods: An integrative review was conducted.