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Ion erosion and carbonization in concrete are the key factors leading to the deterioration of durability. Layered double hydroxides (LDHs) are a kind of functional material with layered structures and ion exchange properties, which can capture a variety of harmful anions in concrete pore solutions. Therefore, LDHs exhibit great potential in improving the durability of concrete as new modified material. This article reviews the recent progress of LDHs. Based on the structural characteristics of LDHs, this work discusses the binding effect of LDHs on Cl−, SO42−{\text{SO}}_{4}^{2-}, and CO32−{\text{CO}}_{3}^{2-} in cement-based materials. We also analyze the influence of LDHs on the physical, mechanical, and hydration properties of cement-based materials and describe the modification mechanisms. Further, the improved durability of concrete and the corrosion inhibition of reinforcement by LDHs were summarized. Finally, we briefly point out some problems in the current research and development trends in the future on LDHs modified cement-based materials.

A whole-cell model represents certain aspects of the cell structure and/or function. Due to the high complexity of the cell, an integrative modeling approach is often taken to utilize all available information including experimental data, prior knowledge and prior models. In this review, we summarize an emerging workflow of whole-cell modeling into five steps: (i) gather information; (ii) represent the modeled system into modules; (iii) translate input information into scoring function; (iv) sample the whole-cell model; (v) validate and interpret the model. In particular, we propose the integrative modeling of the cell by combining available (whole-cell) models to maximize the accuracy, precision, and completeness. In addition, we list quantitative predictions of various aspects of cell biology from existing whole-cell models. Moreover, we discuss the remaining challenges and future directions, and highlight the opportunity to establish an integrative spatiotemporal multi-scale whole-cell model based on a community approach.

Modern coal chemical industry is an important means to realize the clean utilization of coal resources, the coal chemical sludge generated during the process of coal conversion process is a typical refractory solid waste restricting the development of coal chemical industry since its extremely high water content and the poor dewaterability. It has been documented that the dewaterability of coal chemical sludge is affected by the microbial community structure and water distribution characteristics; and thus, it is necessary to investigate the microbial community information and water distribution in coal chemical sludge to provide theoretical guidance for the high-efficiency sludge dewatering technology. In this study, coal-to-olefins sludge and coal-to-oil sludge were selected and the microbial community structure of the two sludge was obtained through analyzing 16s rRNA gene sequencing, and the water distribution was obtained by DSC and LF-NMR method. The results show that the different sewage treatment processes chosen by two coal chemical industries lead to certain differences in the microbial community structures of coal chemical sludge, Proteobacteria, Bacteroidetes and Chloroflexi are the dominant phylum in the two sludge. The LF-NMR method can more accurately measure the water distribution, and the water in the sludge can be classified into bound water, mechanical bound water and free water according. [ABSTRACT FROM AUTHOR]

Through low-cycle reciprocating tests on 11 masonry wall specimens strengthened using reinforced-concrete–masonry composite columns, the effects of the position of the composite column, height-to-width ratio, column reinforcement ratio, and axial load ratio on their load-carrying capacity, stiffness, ductility, and energy dissipation capacity were investigated. It was experimentally found that, by strengthening brick walls with RC–masonry composite columns, the concrete and masonry parts can work together effectively, the failure mode shifts from shear to flexural failure, and the strengthened walls exhibit improved bearing capacity, ductility, and energy dissipation performance compared to unstrengthened masonry walls. It is suggested the composite columns can be placed at the ends of the wall if a strengthening measure is required. For walls with height-to-width ratios greater than 1, placing composite columns in the middle of a wall has little effect on the bearing capacity and stiffness of the wall but can improve the ductility of the wall. The height-to-width ratio is a primary factor influencing the structural performance of masonry walls strengthened using composite columns. A smaller height-to-width ratio leads to higher load-carrying capacity and stiffness but may result in reduced ductility. In comparison, the impact of the column reinforcement ratio and axial load ratio is relatively weaker. The flexural capacity of the masonry wall after strengthening can be obtained using the calculation method for concrete members subjected to a combined action of flexure and compression, in which the compressive strength of the masonry is considered. [ABSTRACT FROM AUTHOR]

Background: The pathogenesis of Alzheimer's disease (AD) is complex. Recent research suggests that AD patients have early disorders in brain cholesterol metabolism. Cholesterol and its derivatives accumulate in neurons, leading to p-Tau overproduction and synaptic dysfunction, initiating AD progression. Calycosin-7-O-β-D-glucoside (CG), a distinctive constituent of Astragali Radix, holds a representative position. Many clinical trials have demonstrated that CG can attenuate cerebral ischemia/reperfusion injury and preserve the structural integrity of the blood-brain barrier. However, whether CG alleviates tau-mediated neurodegeneration by increasing cholesterol efflux after lipid accumulation remains unexplored., Methods: Ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) and multivariate data analysis were employed to investigate metabolic changes in HT22 cells induced by sodium palmitate following 24 hours of CG treatment. The potential therapeutic mechanisms of CG on AD were further examined through Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis., Results: Metabolomic analysis characterized 24 potential biomarkers, revealing that CG could ameliorate cholesterol metabolic pathways. The results of cell experiments revealed that CG can increase the expression of enzyme cholesterol 24-hydroxylase (CYP46A1) (p < 0.05) and the level of 24 hydroxycholesterol (24-OHC) (p < 0.05), reduce the expression of p-Tau (Thr231)/Tau (p < 0.01), inhibit the formation of lipid droplets., Conclusion: CG may inhibit the accumulation of cholesterol and its derivatives in neurons by affecting the CYP46A1-CE-Tau axis, offering a potential therapeutic strategy for AD.