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This study employs computational fluid dynamics (CFD) simulations to investigate the effect of wall roughness on linear loss in circular pipelines. It specifically addresses hemispherical roughness, focusing on how changes in spacing influence linear loss, a critical determinant of fluid motion within pipelines. The simulations further assess the impact of these variables on flow characteristics, laying a theoretical groundwork for drag reduction and pipeline design improvement. Results indicate that increased spacing between roughness elements reduces the differential pressure at both pipeline ends. The dimensionless spacing value of 30 stabilizes this pressure, suggesting a limit to further changes. Additionally, a rise in roughness height at this spacing exacerbates differential pressure, highlighting a proportional relationship between roughness dimensions and linear loss—greater roughness leads to higher linear loss. Applying a nickel-plated coating on the inner wall significantly lowers roughness, thereby reducing linear loss. [ABSTRACT FROM AUTHOR]

Climatic change is a challenge for plant conservation due to plants' limited dispersal abilities. The survival and sustainable development of plants directly depend on the availability of suitable habitats. In this study, we employed an optimized MaxEnt model to evaluate the relative contribution of each environmental variable and predict the suitable habitat for Alsophila costularis under past, current, and future periods, which is an endangered relict tree fern known as a living fossil. For the Last Glacial Maximum (LGM) and Mid‐Holocene scenarios, we adopted two atmosphere–ocean general circulation models: CCSM4 and MIROC‐ESM. The BCC‐CSM2‐MR model was used for future projections. The results revealed that temperature annual range (Bio7) contributed most to the model construction with an optimal range of 13.74–22.44°C. Species distribution modeling showed that current suitable areas were mainly located in most areas of Yunnan, most areas of Hainan, most areas of Taiwan, southeastern Tibet, southwestern Guizhou, western Guangxi, southern Sichuan, and southern Guangdong, with an area of 35.90 × 104 km2. The suitable habitat area expanded northward in Yunnan from the Last Interglacial to the LGM under the CCSM4 model, while a significant contraction toward southwestern Yunnan was found under the MIROC‐ESM model. Furthermore, the potential distributions during the Mid‐Holocene were more widespread in Yunnan compared to those under current period. It is predicted that in the future, the range will significantly expand to northern Yunnan and western Guizhou. Almost all centroids of suitable habitats were distributed in southeastern Yunnan under different periods. The stable areas were located in southwestern Yunnan in all scenarios. The simulation results could provide a theoretical basis for the formulation of reasonable conservation and management measures to mitigate the effects of future climate change for A. costularis. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue in the journal Biology that focuses on the conservation and evolution of wildlife in the context of climate change and human population growth. The issue includes five articles that cover a range of topics related to wildlife conservation. Three articles use species distribution models to predict suitable habitats for endangered species under future climate change. Another article explores variations in egg and clutch size in high-altitude birds, while the final article examines the cultural and medicinal significance of birds and mammals in a national park in Pakistan. The articles provide valuable insights into the effects of climate change and human activity on wildlife conservation and offer suggestions for conservation managers. It is worth noting that all the articles are based on studies conducted in Asian countries, which adds novelty to the research. [Extracted from the article]

The cavitation effect of lubricating film has a significant impact on the seal performance of hydrodynamic pressure mechanical seals.Kerosene-based magnetic fluid lubrication upstream pumping mechanical seal with inclined groove was taken as the research object.By considering the cavitation heat effect as well as the viscous temperature effect, the calculation model of lubricating fluid film was established to study the influences of working conditions and structural parameters on the seal performances using the volume fraction of gas phase in the liquid film as an indicator, and the results were compared with those based on the model only considering the viscous temperature effect. It is found that, due to the cavitation heat model considering the variation of saturated vapor pressure of liquid film medium with temperature,the opening force, leakage rate and volume fraction of vapor phase when considering the thermal effect of cavitation are smaller than the corresponding results when considering the viscosity-temperature effect only, but the variation regularity of each parameter is basically the same under the two conditions. The cavitation effect is enhanced by increasing the rotational speed and the groove diameter ratio, while the cavitation effect is weakened by increasing the inlet pressure, film thickness, radial angle and number of grooves. An increase in rotational speed, groove depth, radial angle, and groove diameter ratio will lead to an increase in leakage rate, while an increase in inlet pressure and groove number can improve sealing performance. [ABSTRACT FROM AUTHOR]

Simple Summary: This study uses Maxent models to explore the impact of global climate change on the potential distribution of 5282 reptile species and to estimate their future conservation status. The analysis reveals that over 52.1% of reptile species are experiencing a decrease in their distributional ranges due to global climate change, resulting in a rapid increase in the number of threatened species. However, some reptiles are experiencing an expansion in their potential distribution range under climate change, leading to 91 endangered species being reclassified as least-concern species. Global climate change drives variations in species distribution patterns and affects biodiversity, potentially increasing the risk of species extinction. Investigating the potential distribution range of species under future global climate change is crucial for biodiversity conservation and ecosystem management. In this study, we collected distributional data for 5282 reptile species to assess their conservation status based on distributional ranges using species distribution models. Our predictions indicate that the potential distribution ranges for over half of these species are projected to decrease under different scenarios. Under future scenarios with relatively low carbon emissions, the increase in the number of threatened reptiles is significantly lower, highlighting the importance of human efforts. Surprisingly, we identified some endangered species that are projected to expand their distribution ranges, underscoring the potential positive effects of climate change on some special species. Our findings emphasize the increased extinction risk faced by reptile species due to climate change and highlight the urgent need to mitigate the effects of habitat degradation and human activities on their potential distribution in the future. [ABSTRACT FROM AUTHOR]