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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.

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.

Different agricultural practices can be beneficial in Miscanthus × giganteus (M × g) phytotechnology applied to post-military and post-mining lands. However, only limited research has focused on supportive treatments using biochar produced from M × g waste. Indeed, when M × g phytotechnology is applied to contaminated soil, the biochar produced through the pyrolysis of the obtained biomass is contaminated, raising concerns about its further application. The current study tested the use of biochar produced from M × g roots cultivated long-term in slightly contaminated soil in the M × g phytotechnology of Cu- or Zn-spiked soils which is important for finding the solution toward valorization of the contaminated biomass. Two biochar doses (1.67 and 5.00%) were evaluated with varying levels of Cu (200 to 416 mg kg-1) or Zn (202 to 580 mg kg-1) concentrations in the soils. This study revealed a beneficial influence of biochar on M × g development, specifically by increasing the plant height and aboveground biomass by up to 20.4 and 115%, respectively. However, the root dry weight increased by 31.8% only at the highest application rate of biochar. The option for valorization of the contaminated biochar in the next phytoremediation process applied to soil contaminated more than the biochar itself was tested. The finding showed the positive influence of biochar on the M × g phytoremediation metrics such as tolerance index, bioconcentration factor, translocation factor, and comprehensive bioconcentration index which ensured the perspective of the proposed approach in the implementation of post-remediation management practice.

Different agricultural practices can be beneficial in Miscanthus × giganteus (M × g) phytotechnology applied to post-military and post-mining lands. However, only limited research has focused on supportive treatments using biochar produced from M × g waste. Indeed, when M × g phytotechnology is applied to contaminated soil, the biochar produced through the pyrolysis of the obtained biomass is contaminated, raising concerns about its further application. The current study tested the use of biochar produced from M × g roots cultivated long-term in slightly contaminated soil in the M × g phytotechnology of Cu- or Zn-spiked soils which is important for finding the solution toward valorization of the contaminated biomass. Two biochar doses (1.67 and 5.00%) were evaluated with varying levels of Cu (200 to 416 mg kg-1) or Zn (202 to 580 mg kg-1) concentrations in the soils. This study revealed a beneficial influence of biochar on M × g development, specifically by increasing the plant height and aboveground biomass by up to 20.4 and 115%, respectively. However, the root dry weight increased by 31.8% only at the highest application rate of biochar. The option for valorization of the contaminated biochar in the next phytoremediation process applied to soil contaminated more than the biochar itself was tested. The finding showed the positive influence of biochar on the M × g phytoremediation metrics such as tolerance index, bioconcentration factor, translocation factor, and comprehensive bioconcentration index which ensured the perspective of the proposed approach in the implementation of post-remediation management practice.

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.

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.