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Studying the potential responses of protected species to global climate change is important for conserving biodiversity. The decline and dieback of Liriodendron chinense Sarg. (L. chinense), an ancient tree species with high ecological and economic value, have been observed in recent years. We aimed to explore the main environmental variables affecting this plant habitat and its future distribution using maximum entropy (MaxEnt). Bioclimatic variables derived from eight Coupled Model Intercomparison Project 6 models, combined with 363 species occurrence records, and multiple environmental factors, were used to predict the potential distribution of the species in the mid and late 21st century under shared socio–economic pathway (SSP) scenarios 126, 245, and 585. The MaxEnt model yielded an excellent performance with an area under the curve value of 0.95. Precipitation in the driest month was the greatest contributor (50.33 %) to habitat distribution, and the Human Influence Index provided indispensable environmental information for the prediction. The habitat loss area was the largest in SSP585-2090s (915,652 km2) and the smallest in SSP126-2090s (271,989 km2). In contrast, the gain area was the largest under SSP126-2090s (18,060 km2), which mainly occurred in the Yangtze River basin (10,625 km2). The SSP126 scenario was the most favorable pathway for the survival of L. chinense, with the most habitat area gained and the least habitat area lost, in which the habitat range showed a notable trend of northward migration in the 21st century. An extreme warming scenario will threaten the habitat of L. chinense, which will have sparse refuge mainly in the Yangtze River and Southeast River basins by the 2090s. These results provide a theoretical basis for developing policies to conserve L. chinense in the face of future climate change.

Based on the 2017 data from the China General Social Survey (CGSS), the conditional process analysis method was used to explore the relationship between physical exercise and subjective well-being, as well as the mediating effect of social capital and the moderating effect of Internet use. This study found that the effect of physical exercise on subjective well-being includes both direct effects and indirect effects. Physical exercise directly and positively affects SWB and partially affects SWB through social networks as a mediating variable. Additionally, Internet use can moderate the direct effect of physical exercise on SWB and the mediating effect of social networks on the relationship between the two. As the frequency of Internet use increases, the link between physical exercise and social capital weakens, resulting in a decreased promotion effect on SWB. The results of this study further reveal the internal mechanism linking physical exercise and the improvement of SWB, which is of great significance for enhancing the accessibility of physical exercise facilities and promoting a healthy online lifestyle, ultimately leading to improved well-being among residents.

In conventional thin materials, the diffraction limit of light constrains the number of waveguide modes that can exist at a given frequency. However, layered van der Waals (vdW) materials, such as hexagonal boron nitride (hBN), can surpass this limitation due to their dielectric anisotropy, exhibiting positive permittivity along one optic axis and negativity along the other. This enables the propagation of hyperbolic rays within the material bulk and an unlimited number of subdiffractional modes characterized by hyperbolic dispersion. By employing time-domain near-field interferometry to analyze ultrafast hyperbolic ray pulses in thin hBN, we showed that their zigzag reflection trajectories bound within the hBN layer create an illusion of backward-moving and leaping behavior of pulse fringes. These rays result from the coherent beating of hyperbolic waveguide modes but could be mistakenly interpreted as negative group velocities and backward energy flow. Moreover, the zigzag reflections produce nanoscale (60 nm) and ultrafast (40 fs) spatiotemporal optical vortices along the trajectory, presenting opportunities to chiral spatiotemporal control of light-matter interactions. Supported by experimental evidence, our simulations highlight the potential of hyperbolic ray reflections for molecular vibrational absorption nanospectroscopy. The results pave the way for miniaturized, on-chip optical spectrometers, and ultrafast optical manipulation. [ABSTRACT FROM AUTHOR]