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In the ecological context of global climate change, ensuring the stable carbon sequestration capacity of forest ecosystems, which is among the most important components of terrestrial ecosystems, is crucial. Forest fires are disasters that often burn vegetation and damage forest ecosystems. Accurate recognition of firegrounds is essential to analyze global carbon emissions and carbon flux, as well as to discover the contribution of climate change to the succession of forest ecosystems. The common recognition of firegrounds relies on remote sensing data, such as optical data, which have difficulty describing the characteristics of vertical structural damage to post-fire vegetation, whereas airborne LiDAR is incapable of large-scale observations and has high costs. The new generation of satellite-based photon counting radar ICESat-2/ATLAS (Advanced Topographic Laser Altimeter System, ATLAS) data has the advantages of large-scale observations and low cost. The ATLAS data were used in this study to extract three significant parameters, namely general, canopy, and topographical parameters, to construct a recognition index system for firegrounds based on vertical structure parameters, such as the essential canopy, based on machine learning of the random forest (RF) and extreme gradient boosting (XGBoost) classifiers. Furthermore, the spatio-temporal parameters are more accurate, and widespread use scalability was explored. The results show that the canopy type contributed 79% and 69% of the RF and XGBoost classifiers, respectively, which indicates the feasibility of using ICESat-2/ATLAS vertical structure parameters to identify firegrounds. The overall accuracy of the XGBoost classifier was slightly greater than that of the RF classifier according to 10-fold cross-validation, and all the evaluation metrics were greater than 0.8 after the independent sample test under different spatial and temporal conditions, implying the potential of ICESat-2/ATLAS for accurate fireground recognition. This study demonstrates the feasibility of ATLAS vertical structure parameters in identifying firegrounds and provides a novel and effective way to recognize firegrounds based on different spatial–temporal vertical structure information. This research reveals the feasibility of accurately identifying fireground based on parameters of ATLAS vertical structure by systematic analysis and comparison. It is also of practical significance for economical and effective precise recognition of large-scale firegrounds and contributes guidance for forest ecological restoration. [ABSTRACT FROM AUTHOR]

This article describes the preparation of structural acrylic adhesives (SAA) with low odor and high strength. Isobornyl methacrylate and methacrylic acid were used as the main monomers. Cumene hydroperoxide was used as a radical polymerization initiator. The effects of tougheners, coupling agents, elastomers, monomers, and peroxide on the performance of acrylic adhesives were studied sequentially. The toughness of acrylic structural adhesives was discovered to be enhanced by the addition of carboxyl-terminated butadiene-acrylonitrile liquid rubber (CTBN) to the acrylic matrix. Coupling agents were added to improve SAA's ability to adhere to steel. The results demonstrated that the SAA performs best when the methacrylic acid's content is 7 wt%, cumene hydroperoxide's content is about 1.5 wt%, CTBN's content is 3 wt%, and the coupling agent's content is 1 wt%. Adhesive modified using 2-hydroxyethylmethacrylate phosphate and CTBN as the toughener provided excellent adhesion to the steel substrate. Its lap shear strength was found to be above 24 MPa, its T-peel strength was up to 8.29 N/mm, and its impact strength was up to 12 kJ/m2. The resulting SAA is capable of meeting structural adhesive bonding strength criteria for steel-to-steel joints. [ABSTRACT FROM AUTHOR]

HSP20 emerges as a novel regulator of autophagy in the heart. Nonetheless, the detailed function of HSP20 in the liver and its effect on autophagy remain unknown. Here, we observed that HSP20 expression is increased in liver tissues from mice and patients with metabolic dysfunction–associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease. Liver-specific downregulation of HSP20 mitigates hepatic steatosis and insulin resistance in obese mice, while upregulating HSP20 promotes lipid deposition and hepatocyte cell death. Mechanistically, liquid chromatography–tandem mass spectrometry revealed that HSP20 interacts with phosphorylated extracellular regulated protein kinase 2 (ERK2) and prevents its dephosphorylation by dual specificity phosphatase 6, leading to ERK2-mediated repression of autophagy and resulting in aggravated saturated fatty acid (SFA)–triggered hepatocyte death. Importantly, such adverse effects could be ameliorated by ERK inhibitor. Our data reveal a framework of how HSP20 increases susceptibility of SFA-induced liver injury through enhancing ERK2 phosphorylation, which represents a plausible therapeutic intervention to combat MASLD. Article Highlights: HSP20 expression was increased in the livers of mice and people living with metabolic dysfunction–associated steatotic liver disease and positively correlated with steatosis grade and body mass. Upregulating HSP20 sensitizes hepatocytes to lipotoxicity by inhibiting autophagy. HSP20 interacts with phosphorylated extracellular regulated protein kinase 2 and prevents its dephosphorylation by phosphatase dual specificity phosphatase 6, leading to aggravation of saturated fatty acid–triggered hepatocyte death by suppressing autophagy function. The HSP20-extracellular regulated protein kinase 2 pathway is an important target to maintain liver homeostasis in patients with metabolic disorders. [ABSTRACT FROM AUTHOR]

To investigate the influence of hybrid effect of different sizes of polypropylene fibers (PPFs) on the compressive constitutive mechanical parameters of roller compacted concrete, nine groups of fiber reinforced concrete specimens containing different sizes of PPFs were designed and the uniaxial compressive testing was conducted. Based on the existing compressive constitutive model and the test stress–strain curves, the peak stress, peak strain, elastic modulus, and the post‐peak stage parameter with different fiber proportion were analyzed and discussed to find the optimum mixing proportion of different sizes of PPF, the calculation of compressive toughness factor were given. The results showed that the addition of PPF could improve the compressive properties of RCC. The axial compressive strength and compressive strain of RCC increased by 3%~16% and 7%~57%, respectively. Meanwhile, the coarse PPF can significantly enhance the ductility of RCC when subjected to uniaxial compressive loading, and the group of multi‐scale PPF hybridization had higher compressive toughness than groups blended with two types of PPF, showing a more obvious positive hybrid effect. Finally, multi‐scale fiber hybrid effect function was proposed, the results showed that the function can well reflect the influence of fiber hybrid effect on the compressive properties of RCC and can be used to predict the optimal fiber proportion of fiber reinforced concrete. [ABSTRACT FROM AUTHOR]