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Objective It is aimed to investigate the fatigue damage of an antenna bracket structure installed at urban rail transit vehicle bogie frame end under random vibration excitation, and improvement measures are proposed. Method Finite element modeling of the antenna bracket system is conducted using finite element analysis software. Modal analysis of the structure is performed, and the on-site measured vibration ASD (acceleration spectral density) from the track is used as the load excitation instead of the standard spectrum. A random vibration simulation of the antenna bracket is conducted using fatigue analysis software nCode to obtain the bracket fatigue damage result. Improvement measures are proposed for the fatigue weak points of the bracket, and the effectiveness of the improvement measures is verified. Result & Conclusion Simulation results reveal that the fatigue weak points of this structure are at the roots of the reinforcement plates on bracket both sides, with a maximum total damage of 15.58, failing to meet application requirements. The improvement measures involve locally thickened plate roots on bracket both sides and adding support ribs on the sides. After implementing these measures, the fatigue damage value of the bracket significantly decreased, with a maximum total damage of 0.02, meeting application requirements, thereby verifying the effectiveness of the improvement scheme.

Postbiotics are inanimate microbial cells and/or their components as well as microecological preparations made from their metabolites, which are beneficial to the health of the host. Postbiotics can regulate intestinal microbial balance, enhance immunity, and have anti-inflammatory and antibacterial effects. Compared with probiotics, living bacterial cells, postbiotics are safer, and more stable, effective and convenient. This article summarizes the origin, microbial sources, preparation methods and advantages of postbiotics, and elucidates the mechanisms of action of postbiotics in comparison with those of probiotics. In addition, it introduces readers to the applications of postbiotics as functional food supplements, food quality improvers, food preservatives and detoxifying agents in foods. We believe that as the definition, classification, and functional components of postbiotics become clearer, they will be more widely used in the fields of foods, nutraceuticals, foods for special medical purpose, infant foods, and personal care products. The development of postbiotics will also promote the leapfrog development of basic and applied science.

In steep wildfire-burned terrains, intense rainfall can produce large runoff that can trigger highly destructive debris flows. However, the ability to accurately characterize and forecast debris flow susceptibility in burned terrains using physics-based tools remains limited. Here, we augment the Weather Research and Forecasting Hydrological modeling system (WRF-Hydro) to simulate both overland and channelized flows and assess postfire debris flow susceptibility over a regional domain. We perform hindcast simulations using high-resolution weather-radar-derived precipitation and reanalysis data to drive non-burned baseline and burn scar sensitivity experiments. Our simulations focus on January 2021 when an atmospheric river triggered numerous debris flows within a wildfire burn scar in Big Sur-one of which destroyed California's famous Highway 1. Compared to the baseline, our burn scar simulation yields dramatic increases in total and peak discharge and shorter lags between rainfall onset and peak discharge, consistent with streamflow observations at nearby US Geological Survey (USGS) streamflow gage sites. For the 404 catchments located in the simulated burn scar area, median catchment-area-normalized peak discharge increases by ∼ 450% compared to the baseline. Catchments with anomalously high catchment-area-normalized peak discharge correspond well with post-event field-based and remotely sensed debris flow observations. We suggest that our regional postfire debris flow susceptibility analysis demonstrates WRF-Hydro as a compelling new physics-based tool whose utility could be further extended via coupling to sediment erosion and transport models and/or ensemble-based operational weather forecasts. Given the high-fidelity performance of our augmented version of WRF-Hydro, as well as its potential usage in probabilistic hazard forecasts, we argue for its continued development and application in postfire hydrologic and natural hazard assessments.

Osteopontin (OPN) is a secreted phosphosylated protein, which is widely found in various tissues and body fluids. OPN involved in various physiological and pathological processes such as bone growth, wound healing and cell adhesion and migration. The integrin αvβ3 is the main receptor for OPN. Recent studies have shown that the high expression level of OPN is closely related to the invasive phenotype and poor prognosis of non-small cell lung cancer (NSCLC) . OPN is expected to become a potential serological biomarker and therapeutic drug target for the disease, which has gradually attracted the attention of researchers at home and abroad. Therefore, this paper presents the structural characteristics of OPN and its correlation with the occurrence, development and treatment prognosis of NSCLC.