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Segmental tunnel lining strengthened with steel plates is widely used worldwide to provide a permanent strengthening method. Most existing studies assume an ideal steel-concrete interface, ignoring discontinuous deformation characteristics, making it difficult to accurately analyze the strengthened structure's failure mechanism. In this study, interfacial fracture mechanics of composite material was applied to the segmental tunnel lining strengthened with steel plates, and a numerical three-dimensional solid nonlinear model of the lining structure was established, combining the extended finite element method with a cohesive-zone model to account for the discontinuous deformation characteristics of the interface. The results accurately describe the crack propagation process, and are verified by full-scale testing. Next, dynamic simulations based on the calibrated model were conducted to analyze the sliding failure and cracking of the steel-concrete interface. Lastly, detailed location of the interface bonding failure are further verified by model test. The results show that, the cracking failure and bond failure of the interface are the decisive factors determining the instability and failure of the strengthened structure. The proposed numerical analysis is a major step forward in revealing the interface failure mechanism of strengthened composite material structures. [ABSTRACT FROM AUTHOR]

Systemic metabolic syndrome significantly increases the risk of morbidity and mortality in patients with non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). However, no effective therapeutic strategies are available, practically because our understanding of its complicated pathogenesis is poor. Here we identify the tripartite motif-containing protein 31 (Trim31) as an endogenous inhibitor of rhomboid 5 homolog 2 (Rhbdf2), and we further determine that Trim31 directly binds to Rhbdf2 and facilitates its proteasomal degradation. Hepatocyte-specific Trim31 ablation facilitates NAFLD-associated phenotypes in mice. Inversely, transgenic or ex vivo gene therapy-mediated Trim31 gain-of-function in mice with NAFLD phenotypes virtually alleviates severe deterioration and progression of steatohepatitis. The current findings suggest that Trim31 is an endogenous inhibitor of Rhbdf2 and downstream cascades in the pathogenic process of steatohepatitis and that it may serve as a feasible therapeutical target for the treatment of NAFLD/NASH and associated metabolic disorders. Nonalcoholic steatohepatitis (NASH) is a chronic liver disease with complex disease mechanisms. Here the authors report that the E3 ubiquitin-protein ligase Trim31 mitigates development of NASH via inhibition of rhomboid 5 homolog 2 (Rhbdf2) in mice. [ABSTRACT FROM AUTHOR]

The Yao'an Pb-Ag deposit, located in the Chuxiong Basin, western Yangtze Block, is an important component of the Jinshajiang-Ailaoshan alkaline porphyry-related polymetallic intrusive belt. This complex suite of rock bodies includes a vein of pseudoleucite porphyry within deposits of syenite porphyry and trachyte. The pseudoleucite is characterized by a variable greyish, greyish-white, and greyish-green porphyritic texture. Phenocrysts are mainly pseudoleucite with small amounts of alkali feldspar and biotite. In an intense event, leucite phenocrysts altered to orthoclase, kaolinite, and quartz. Both the pseudoleucite porphyry and the syenite porphyry samples were typical alkali-rich, K-rich, al-rich rocks with high La/Yb ratios; enriched in light rare earth elements and large-ion lithophile elements, and depleted in high field strength elements; and with strongly negative Ta, Nb, and Ti (TNT) anomalies and slightly negative Eu anomalies-all characteristics of subduction-zone mantle-derived rock. We obtained a LA-ICP-MS zircon U-Pb age of 34.1 ± 0.3 Ma (MSWD = 2.4), which is younger than the established age of the Indian and Eurasian Plate collision. The magma derived from a Type-II enriched mantle formed in a post-collisional plate tectonic setting. The geochemical characteristics of the Yao'an pseudoleucite porphyry are powerful evidence that the porphyry's development was closely linked to the Jinshajiang-Ailaoshan fault and to the Indian-Eurasian collision. [ABSTRACT FROM AUTHOR]

This paper reports a simple method of fabricating self-aligned offset gate (SAOG) polycrystalline silicon (poly-Si) thin film transistors (TFTs). The SAOG structure was formed by two key steps, i.e. an isotropic photoresist trimming and an additional gate fringe etching. The fabricated SAOG devices with this proposed method exhibit a significantly suppressed off-current increase with gate bias compared with the non-offset ones, and have identical bi-directional transfer characteristics under reversed source/drain biases. It is also shown that the performances of poly-Si TFTs with metal-induced lateral crystallization can be improved significantly by annealing in forming gas. [ABSTRACT FROM AUTHOR]

We report an experimental investigation of secondary reactions of intermediates in delayed coking. Thermal cracking reactions of intermediates, for example coker naphtha (C ~180 °C), light coker gas oil (LCGO, 180-350 °C), middle coker gas oil (MCGO, 350-440 °C), and heavy coker gas oil (HCGO, >440 °C), were investigated. The results reveal that cracking of coker naphtha and LCGO is low under these experimental conditions. Thermal cracking MCGO exceeds that of LCGO. Among all the intermediates, thermal cracking is greatest for HCGO. The secondary reactions of HCGO produce not only gas and liquid products, but also coke. This increase in the yields of gas and coke is attributed to secondary reactions of HCGO and MCGO. Inhibition of the secondary reactions of intermediates results in a greater yield of liquid. [ABSTRACT FROM AUTHOR]

Ternary alloys of CdS xSe1− x nanorods have been synthesized by the thermal treatment of Cd2+ dispersed polyethylene glycol 2000 gel (PEG2000) with ethylenediamine solution of sulfur and selenium in a sealed system at 180 °C for 24 h, during which the proportion between S and Se in the nanorods was controlled by the ratios of every starting material to each other. The alloyed ternary CdS xSe1− x nanorods are highly crystalline without any other phase. The optical property these nanorods could be manipulated by modulating the composition of S and Se. [ABSTRACT FROM AUTHOR]

In this paper, a comprehensive risk assessment system is proposed to evaluate the risk of collapse in mountain tunnels. This system integrates risk source identification, dynamic and static risk classification, deep learning prediction, and engineering risk evaluation. Firstly, risk events and sources are identified, and a risk evaluation method combines the fuzzy analytic hierarchy process (FAHP) and interval technique for order preference by similarity to ideal solution (TOPSIS). FAHP is used to calculate weights, and a risk classification table based on five classical values is derived using traditional TOPSIS. The actual project’s risk value is then calculated using Interval TOPSIS to determine the risk level. Secondly, six models (BP, SVM, CNN, LSTM, PSO-SLTM, and EPL) are trained and tested to predict surface settlement at the tunnel portal and using RMSE, MAE, and maximum (minimum and average) error values for comparison; the best model is determined. The study concludes that a two-stage model, which uses ensemble empirical mode decomposition to process raw data and particle swarm optimization to optimize long short-term memory hyperparameters, provides the best predictive results. Finally, static and dynamic risks are combined for a comprehensive risk evaluation. The Aktepe Tunnel Project in Xinjiang, China, serves as a case study to successfully and accurately forecast surface settlement and evaluate the safety of the tunnel portal. This assessment confirms that this section of the tunnel is at average risk and that the current building conditions ensure the safety of the tunnel, the case study validates the rationality of the comprehensive evaluation system, offering a reference for tunnel portal risk evaluation. [ABSTRACT FROM AUTHOR]