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The increase of energy in the climate system caused by anthropogenic climate change is expected to disrupt predictable weather patterns and result in greater temperature extremes.1,2 As a result of these climate shifts, El-Niño Southern Oscillation (ENSO), which drives predictable periods of hot/dry and cool/wet across the Pacific, is expected to increase in variability and magnitude.3 These changes will significantly impact ectotherms, whose performance across a range of behaviors is dependent on local environmental temperatures.4 As such, we must understand the way individuals experience climate conditions and how changes in their body temperature (Tb), whether through climate or modification of their thermoregulatory mechanisms,5 affect their performance. Laboratory studies have shown that estuarine crocodile (Crocodylus porosus) diving and swimming performance is reduced above 32°C-33°C,6,7,8 temperatures commonly exceeded across their natural range. By monitoring Tb and diving activity in 203 free-ranging estuarine crocodiles over 15 years, we show that the Tb of crocodiles has increased alongside rising air temperatures since 2008, reflecting the climatic shifts caused by the ENSO cycle. As ambient temperatures rose, crocodiles experienced more days close to critical thermal limits (32°C-33°C), at which temperatures the duration of dives was reduced and the prevalence of active cooling behavior was elevated. This study demonstrates that crocodiles are susceptible to multi-year fluctuations in ambient temperature, which requires them to undertake concomitant changes in behavior. They are already close to their physiological thermal limit, but the impact of future predicted rises in temperature remains unknown.

Background: In recent years, the integration of renewable energy sources into the grid has increased exponentially. However, one significant challenge in integrating these renewable sources into the grid is intermittency. Objective: To address this challenge, accurate PV power forecasting techniques are crucial for operations and maintenance and day-to-day operations monitoring in solar plants. Methods: In the present work, a hybrid approach that combines Deep Learning (DL) and Numerical Weather Prediction (NWP) with electrical models for PV power forecasting is proposed Results: The outcomes of the study involve evaluating the performance of the proposed model in comparison to a Physical model and a DL model for predicting solar PV power one day ahead and two days ahead. The results indicate that the prediction accuracy of PV power decreases and the error rates increase when forecasting two days ahead, as compared to one day ahead. Conclusion: The obtained results demonstrate that DL models combined with NWP and electrical models can improve PV Power forecasting compared to a Physical model and a DL model.

Abstract This paper investigates the forced convection of alumina-water nanofluids within helical tubes, maintaining a constant wall temperature and assuming thermal equilibrium between the nanoparticles and the base fluid. The nanofluid model incorporates the effects of alumina (Al2O3) nanoparticle volume fraction, diameter, and temperature on thermophysical properties. The governing equations are solved using the Forward-Time Central-Space Finite Volume method in conjunction with the simple algorithm. Numerical results are validated against experimental data, demonstrating high accuracy. The study explores the effects of pitch size, curvature ratio, nanoparticle volume fraction, nanoparticle diameter, and Reynolds number on velocity contours, temperature profiles, secondary flow, thermophysical properties, friction coefficient, and heat transfer rate. Additionally, the figure of merit evaluates the impact of these parameters on the thermal performance of the system. The results indicate that an increase in Reynolds number and nanoparticle diameter negatively affects thermal performance, while higher nanoparticle volume fraction, curvature ratio, and pitch size enhance it. Furthermore, incorporating nanoparticles in straight tubes proves to be more advantageous compared to helical tubes. This study tested volumetric ratios of 1%, 2%, and 4%, which resulted in increases in heat transfer coefficients of 21%, 32%, and 43%, respectively, compared to pure water under similar conditions, such as Reynolds number and coil pitch.

We developed an innovative high-temperature shock (HTS) technique to synthesize uniformly coated materials, resulting in enhanced surface structures, improved cycling stability, and pouch cells retaining over 70% capacity after 700 cycles.

Background: Active breaks and very low- to low-intensity exercises such as walking or cycling at an active desk have been shown to significantly counteract the negative effect of prolonged sedentary behaviors. The objective was to investigate the effect of physical activity level (PAL) on changes in energy expenditure (EE), heart rate, and substrate oxidation from sit-to-stand and sit-to-light cycling. Methods: Fifty healthy young males and females (age: 23.9 [3.9] y, body mass index: 22.9 [2.3] kg/m2) were submitted to a fixed 1 hour session of different posture allocations: 15-minute sitting, 15-minute standing, 15-minute sitting, and 15-minute very low-intensity cycling. EE, substrate oxidation rates, and heart rate were continuously assessed throughout the experimental visit. Data were then compared between participants according to their PAL in tertiles (low, medium, or high). The high-PAL group showed lower sedentary time (P < .0001) and higher time spent in low (P < .0001), moderate (P < .0001), and vigorous physical activity (P = .0034). Results: ANOVA’s analysis showed that EE significantly increased when standing (+11%) and cycling (+94%) relative to the seated position (P < .05) without any differences between groups. There was also a significant increase in heart rate during standing and cycling compared with sitting (P < .05) without any differences between groups. Relative EE (in kilocalories per minute per kilogram) was significantly higher when seated (P < .05) independent of PAL but marginally higher in the high-PAL group when standing relative to the medium-PAL group (P = .06). Conclusion: The findings of this study suggest that people’s PAL does not impact energetic and metabolic adaptations during sit-to-stand and sit-to-very-light-intensity cycling exercise.