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TiN coatings are one of the most widely used nitride coatings. The introduction of the light metal element Si has led to the formation of TiN-Si3N4 coatings with a two-phase nanocomposite structure. However, the high friction coefficient of TiN-Si3N4 coatings at room temperature limits their application. In order to further improve its lubrication properties, we tried to incorporate the lubricating phase Ag. TiN-Si3N4-Ag composite coatings were prepared using a multi-target magnetron sputtering by fixing the Ti-Si target power and adjusting the Ag target power. Their microstructure, mechanical and tribological properties depending on the Ag target power were investigated. The results showed that the TiN-Si3N4-Ag composite coatings exhibited the crystalline TiN and Ag phase, and amorphous Si3N4 phase. The increasing Ag target power increased the coating surface roughness from 7 to 52 nm. The nano-hardness (H), elastic modulus (E), resistance against elastic strain to failure (H/E), and the resistance against plastic strain to failure (H3/E2) of the TiN-Si3N4-Ag composite coating first increased and then decreased with the increase of Ag target power. As the Ag target power was 10 W, the hardness (9.43 ± 0.45 GPa), elastic modulus (265.29 ± 13.3 GPa), H/E (0.036), and H3/E2 (0.0119 GPa) of the TiN-Si3N4-Ag composite coating reached the maximum values, indicating this coating exhibiting the better mechanical properties. After adding Ag, the coating exhibited better lubricating effect, while the wear resistance of the coating increased. [ABSTRACT FROM AUTHOR]

Emerging evidence suggests that atherosclerosis, one of the leading phenotypes of cardiovascular diseases, is a chronic inflammatory disease. During the atherosclerotic process, immune cells play critical roles in vascular inflammation and plaque formation. Meanwhile, gastrointestinal disorder is considered a risk factor in mediating the atherosclerotic process. The present study aimed to utilize sivelestat, a selective inhibitor of neutrophil elastase, to investigate its pharmacological benefits on atherosclerosis and disclose the gastrointestinal–vascular interaction. The activation of intestinal neutrophil was increased during atherosclerotic development in Western diet-fed ApoE-/- mice. Administration of sivelestat attenuated atherosclerotic phenotypes, including decreasing toxic lipid accumulation, vascular monocyte infiltration, and inflammatory cytokines. Sivelestat decreased intestinal permeability and endotoxemia in atherosclerotic mice. Mechanistically, sivelestat upregulated the expression of zonula occludens-1 in the atherosclerotic mice and recombinant neutrophil elastase protein-treated intestinal epithelial cells. Meanwhile, treatment of sivelestat suppressed the intestinal expression of inflammatory cytokines and NF-κB activity. In contrast, administration of lipopolysaccharides abolished the anti-atherosclerotic benefits of sivelestat in the Western diet-fed ApoE-/- mice. Further clinical correlation study showed that the circulating endotoxin level and intestinal neutrophil elastase activity were positively correlated with carotid intima-medial thickness in recruited subjects. In conclusion, sivelestat had pharmacological applications in protection against atherosclerosis, and intestinal homeostasis played one of the critical roles in atherosclerotic development. [ABSTRACT FROM AUTHOR]

Emerging evidence suggests that microRNAs (miRNAs) are essential for metabolic haemostasis of liver tissues. Among them, miR‐33a is supposed to modulate the cholesterol export and fatty acid oxidation, but whether miR‐33a involves in the process of fatty liver disease is unclear. To disclose the hypothesis, we utilized miR‐33a mimic and antisense to explore their effects in primary hepatocytes or high‐fat diet (HFD)‐fed mice. Treatment with palmitic acid (PA) or HFD significantly increased the expression of miR‐33a in hepatocytes or liver tissues. In primary hepatocytes, miR‐33a mimic decreased mitochondrial function, including reduction of ATP production and oxygen consumption, whereas miR‐33a inhibition protected PA‐induced mitochondrial dysfunction. Interestingly, miR‐33a selectively suppressed mitochondrial complex I activity and protein expression, but not other complexes. Through bioinformatics prediction, we found miR‐33a directly targeted on the 3′‐UTR of NDUFA5. Dual‐luciferase reporter analysis further confirmed the direct suppression of miR‐33a on NDUFA5 expression. More importantly, administration of miR‐33a antisense could effectively restore HFD‐induced mitochondrial dysfunction through up‐regulation of NDUFA5 levels. Mice treated with miR‐33a antisense also exhibited improved liver function and structural disorders under obese status. Taken together, miR‐33a was an important mediator of hepatocyte mitochondrial function, and the therapeutic benefits implied miR‐33a antisense had the potential clinical application in combating the fatty liver disease. [ABSTRACT FROM AUTHOR]

Underground coal mining can result in land deformation (e.g., land subsidence and ground fissures), and may consequently change the soil nutrients. Soil organic matter (SOM), total nitrogen (TN), and available phosphorus (AP) are critical indicators of soil fertility and eco-restoration in mining areas. In this study, soil samples (depth: 0–20 cm) were collected twice from 20 sampling points in pre-mining and post-mining in the No.12 panel of Caojiatan coalfield, in the Loess Plateau of China. SOM, TN, and AP in soil samples were measured, and the nutrient loss was evaluated. Ten environmental factors affecting soil nutrient loss were identified from a 5-m resolution digital elevation map (DEM). The paired t-test was utilized to evaluate the differences between SOM, TN, and AP in pre-mining and post-mining soil. The mechanisms of the effects of environmental factors on soil nutrient loss were revealed based on multiple linear regression, redundancy analysis (RDA), and the random forest algorithm (RF). Ordinary kriging and RF were utilized to predict and optimize the spatial distribution of the soil nutrient loss. The results showed that significant differences existed between the SOM, TN, and AP in the pre-mining and post-mining soil. The model established by RF provided a higher accuracy in terms of fitting the correlation between soil nutrient loss and environmental factors compared to the model established by multiple linear regression, and the feature importance obtained by RF showed that profile curvature, distance to working panel margin, and surface roughness were the most significant factors affecting the loss of SOM, TN, and AP, respectively. This study provides a theoretical reference for eco-restoration, as well as soil and water conservation, in subsided lands in coalfields. [ABSTRACT FROM AUTHOR]

The nonlinear and heterogeneous responses of nutrients to eutrophication control measures are a major challenge for in situ treatment engineering design, especially for large water bodies. Tackling the problem calls for a full understanding of potential water quality responses to various treatment schemes, which cannot be fulfilled by empirical-based methods or small-scale tests. This paper presents a methodology for Phoslock application based on the idea of object-oriented intelligent engineering design (OOID), which includes numerical simulation to explore the features of responses to numerous assumed schemes. A large plateau lake in Southwestern China was employed as a case study to illustrate the characteristics of the water quality response and demonstrate the applicability of this new approach. It was shown by the simulation and scenario analysis that the water quality response to Phoslock application always reflected nonlinearity and spatiotemporal heterogeneity, and always varied with objects, boundary conditions, and engineering design parameters. It was also found that some design parameters, like release position, had a significant impact on efficiency. Thus, a remarkable improvement could be obtained by cost-effective analysis based on scenarios using combinations of design parameters. [ABSTRACT FROM AUTHOR]