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Research on the scraping effects of rock–ice avalanches remains relatively limited. This study investigates the evolution of rock–ice avalanches with varying ice content and initial accumulation forms during motion, scraping, and deposition using laboratory physical model experiments. Changes in pre- scraping velocity, scraping length, scraping depth, maximum deposition length, and deposition thickness were analyzed as functions of ice content. The analysis revealed the influence of ice content and initial accumulation on scraping effects, as well as on motion and deposition characteristics. The experimental results indicate that, compared to typical debris flows (without ice), the presence of ice significantly enhances the mobility, deposition features, and scraping effects of rock–ice avalanches. Through analysis, it is shown that the low friction of ice debris enhances the kinetic energy of ice-rock debris flows, thereby increasing the energy required for scraping. [ABSTRACT FROM AUTHOR]

A DEM numerical approach is employed to illustrate the critical stress development of a three-supporting cable flexible barrier under a large scale stony debris movement impact. A proper linear parallel bond is applied to build the flexible barrier model. Critical state is presented by lowering the tensile resistance of the flexible barrier and steepening the channel slope. The tensile stress of the supporting cables is primarily studied. Results mainly indicate that the particle-structure contact is essential to the stress development. The bottom cable always exhibits larger tensile stress due to the massive collision and compressive force of particles and the tensile force exerted by the vertical cable-net joint system. On the other hand, the intermediate cable receives lower collision and compressive force, resulting in smaller tensile stress. The bottom cable indicating numerous direct particle-structure contact part performs brittle failure, which is analogous to the concentrated load feedbacks. The loading of the intermediate one reaches ductile failure, reflecting the desirable effect of dispersing loads. This study suggests that practical engineering should try to avoid massive boulder impact or reinforce the bottom cable in order to improve the hazard prevention design.

As an important weather extreme, gales greatly impact the air quality, agriculture, aviation, and renewable energy in North China. However, the spatial–temporal changes in gale events remain unknown in North China. In this study, using the ERA5 reanalysis with high spatiotemporal resolution and multi-model simulations from the Coupled Model Intercomparison Project Phase Six (CMIP6), we investigate the temporal changes, including daily, seasonal and decadal variations in gale events in North China between 1980 and 2021, and we project the changes in gale events in the mid and late 21st century under two shared socio-economic pathways (SSPs). The gale events show large spatial heterogeneity in frequency, with a high frequency of >25 days/year in central Inner Mongolia province, northern Hebei province, and northwestern Beijing. Over the past four decades, the gale events in North China have shown a decadal reversal, with a decrease between 1980 and 2006 and an increase between 2007 and 2014. Furthermore, the gale events show strong temporal variations in North China. For seasonal variation, the gale events exhibit double peaks, with the largest peak in April and the smallest peak in October. For daily variation, the gale events show a single peak, with the maximum from 10:00 to 16:00 local time in North China. Multi-model simulations from CMIP6 reveal a continuous decreasing trend of gale events in North China by the end of the 21st century under both SSP1-2.6 and SSP2-4.5 scenarios relative to the historical period. Our results provide comprehensive support for planning aviation, renewable energy, and agriculture in the future. [ABSTRACT FROM AUTHOR]

Introduction: Neuropathic pain (NP) is one of the most severe chronic pain types. In recent years, more and more studies have shown that long noncoding RNA (LncRNA) plays a key role in a variety of human diseases, including NP. However, the role of LncRNA prostate cancer-associated transcript 19 (PCAT19) in NP and its specific mechanism remain unclear. Methods: A chronic constrictive injury (CCI) rat model was established. Rat paw withdrawal threshold and paw withdrawal latency were used to evaluate the neuronal pain behavior of rats in this model. mRNA expression of PCAT19, neuroinflammatory factor, microRNA (miR)-182-5p, and Jumonji domain containing 1A (JMJD1A) were detected by quantitative real-time PCR. ELISA analysis was used to detect inflammatory factor protein expression. Dual-luciferase reporter assay was used to evaluate the targeting relationship between genes. Results: PCAT19 was continuously upregulated in CCI rats. miR-182-5p was the target of PCAT19, and miR-182-5p was increased after PCAT19 knockdown. NP behaviors such as mechanical ectopic pain and thermal hyperalgesia as well as neuroinflammation can be reduced by knocking down PCAT19. However, the injection of miR-182-5p antagomir significantly reversed the level of the NP behaviors and neuroinflammation caused by PCAT19 knockdown. Besides, dual-luciferase reporter assay showed that JMJD1A was the target gene of miR-182-5p. The level of JMJD1A in CCI rats increased with time. After PCAT19 knockdown, JMJD1A was significantly decreased, but inhibition of miR-182-5p can reverse its levels. Conclusion: This study shows that PCAT19 plays a role in NP by targeting the miR-182-5p/JMJD1A axis, and PCAT19 can be used as a new therapeutic target for NP. [ABSTRACT FROM AUTHOR]