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OBJECTIVE: Osteoarthritis (OA) is associated with decreased autophagy activity and imbalance of cell homeostasis in chondrocytes (CHs). Sirtuin 7 (Sirt7) is claimed to have the ability to activate the autophagy response. The aim of this study was to explore the function of Sirt7 in the development of OA involving autophagy by culturing human chondrocytes (CHs). PATIENTS AND METHODS: We collected knee joint cartilage from patients undergoing traumatic amputation and arthroscopic knee replacement. Protein and mRNA levels of collagen II, Sirt7, ULK1, Lc3, and Beclin1 were analyzed by Western blot and RT-PCR. CHs were isolated from the traumatic cartilage as a control group, and IL-1β was used to induce CHs degeneration. The expression of Sirt7 gene was silenced by siRNA and upregulated by recombinant human Sirt7 protein (rh-Sirt7). An autophagy activator Tat-beclin 1 (Tat) was used to activate autophagy in cultural CHs. Expression of collagen II, Sirt7, ULK1, Lc3, and Beclin1 was determined by immunofluorescence, Western blot, and RT-PCR, respectively. RESULTS: The protein and mRNA levels of Collagen II, Sirt7, ULK1, Lc3-II, and Beclin1 expressions were decreased in OA cartilage compared with those in healthy cartilage. IL-1β degenerated the CHs resulting in a reduction of collagen II, which also downregulated Sirt7, ULK1, Lc3-II, and Beclin1. Sirt7 deficiency accelerated the catabolism of collagen II and weakened the expression of ULK1, Lc3-II, and Beclin1. On the contrary, exogenous rh-Sirt7 played a positive role in these gene expressions. Finally, Tat alleviated the CHs degeneration by upregulating collagen II and activating ULK1, Lc3-II, and Beclin1, but incapable to mediate Sirt7 expression. CONCLUSIONS: Overall, these findings suggested that Sirt7 was suppressed in the degenerated cartilage. Sirt7 deficiency does harm to the autophagy level, affecting CHs metabolism, while the upregulation of Sirt7 activated autophagy and protected CHs degeneration. An appropriate increase in autophagy can protect CHs but has no effect on Sirt7 expression. [ABSTRACT FROM AUTHOR]

To determine the influence of different bulk densities and texture on soil water infiltration after remediation in gravel-mulched areas, we subjected two different soil types were to a battery of tests to determine their soil infiltration characteristics. The results show that the soil infiltration capacity decreases with increasing soil bulk density. A logarithmic negative correlation was identified between stable infiltration rate and the bulk density of the two soils (R2 > 95%). Moreover, the larger the bulk density, the smaller the cumulative infiltration, and there is a significant linear negative correlation between density and infiltration. The Kostiakov infiltration model better describes the infiltration process of the Lou soil at all stages and the infiltration of Yellow-brown soil before 40 min. Finally, as soil water is redistributed, and its content increases with soil depth, and the greater the bulk density, the greater the water storage capacity of the soil from 0 to 30 cm. Overall, the soil bulk density should be no less than 1.5 g/cm3 when Lou soil is chosen to cover on gravel-mulched land, and not less than 1.4 g/cm3 for Yellow-brown soil. [ABSTRACT FROM AUTHOR]

Today, air pollution is a great issue, and the transport sector is an important emission source. In this study, we present an integrated land use, transport, and environment model in which transport-related pollutants are assumed to influence people's housing location choices, and a continuum modeling approach is applied. The pollutants generated by the transport sector are dispersed by the wind and they affect air quality. The air quality changes people's housing choices, which in turn changes their travel behavior. We assume that the road users are continuously distributed over the city, that the road network is relatively dense, and that this network can be approximated as a continuum. The total demand is categorized into several classes, and the modeled region contains several subdistricts. People who live in different subdistricts or who belong to different classes of commuters are assumed to have different perceptions of travel time, air quality, and the housing provision–demand relationship. The finite element method and the Newton–Raphson algorithm are adopted to solve this problem, and a numerical valuation is given to illustrate the effectiveness and efficiency of the proposed model. [ABSTRACT FROM PUBLISHER]

Focuses on a study which performed a rapid removal of photoresist assisted by a large-area electron beam in an oxygen atmosphere. Methodology of the study; Results; Conclusions.