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Purpose: In order to solve the problem of the high cost of backfill and eliminate the use of Gobi aggregate for backfill in the Kalatongke copper-nickel mine. Method; The feasibility of slag for backfill is demonstrated by conducting laboratory and industrial tests. The pumpability and strength characteristics of two types of backfill slurry were studied by slump and uniaxial compressive strength(L/CS) tests respectively. The two types of backfill slurry were using different aggregates. One was only using unclassified tailings backfill as aggregates,and the other was using unclassified tailings and slag as aggregates. Result; The results show that the suitable transporting solid concentrations of unclassified tailings backfill slurry are 66% -- 68%and that the suitable transporting solid concentrations of unclassified tailings and slag filling slurry backfill slurry are 70% -- 72% with 20% -- 30%of slag aggregate. The 28 d UCS of unclassified tailings backfill is lower than 3 MPa,and the addition of slag as coarse aggregate can improve the strength of the backfill. When the amount of slag added is less than 30%, the strength of backfill will increase with the increased addition of slag. Conclusion: The bottom layer backfill of stope should use the composite aggregate of unclassified tailings and slag. When the proportion of slag aggregate is 20% -- 30%,there is no slag segregation inside the backfill test block. Significance; In this paper, high-density slag is innovatively applied to mine backfill. The research results can help guide the backfill process of Kalatongke copper-nickel mine and provide a reference for the bulk utilization of slag in Xinjiang area. [ABSTRACT FROM AUTHOR]

Sirt6 has been reported to play a protective role in macrophage foam cell formation, but whether Sirt6 controls atherosclerosis plaque stability and whether it can reduce the interaction between endothelial cells and macrophages remains unclear. The aim of this study was to investigate the effect of Sirt6 on atherosclerosis plaque stability and the underlying mechanisms. We used Tie2-Cre transgenic mice as a Cre-lox tool to delete Sirt6 floxed sequences in endothelial cells during adulthood to establish [Sirt6.sup.-/-] mice. [ApoE.sup.-/-]:[Sirt6.sup.-/-] and [ApoE.sup.-/-]:Sirt6Tg mice were used in our investigation. After a 16 week high-fat diet, the mice developed markedly atherosclerotic plaques. Sirt6 knockout exacerbated atherosclerotic plaque progression in both size and stability. In vitro, murine macrophage RAW264.7 cells were treated with ox-low density lipoproteins for 24 h to simulate atherosclerosis. Furthermore, Sirt6 overexpression remarkably increased autophagic flux in macrophages and inhibited macrophage apoptosis. Moreover, Sirt6 overexpression inhibited the expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and platelet selectin (P-selectin), leading to reduced infiltration of macrophages and foam cells. In conclusion, our study indicates a new mechanism-based strategy to therapeutically stimulate atherosclerosis plaque stability. Key words: foam cells, obesity, lipoproteins, vascular biology, apolipoproteins. On rapporte que Sirt6 joue un rôle protecteur dans la formation de cellules spumeuses, mais on ignore si Sirt6 contrôle la stabilité de la plaque d'athérosclérose et s'il peut réduire l'interaction entre les cellules endothéliales et les macrophages. L'objectif de cette étude était d'examiner l'effet de Sirt6 sur la stabilité de la plaque d'athérosclérose et les mécanismes sous-jacents. Les auteurs ont utilisé des souris transgéniques Tie2-Cre comme outil Cre-lox afin de retirer les séquences Sirt6 flanquées des sites lox (<>) dans les cellules endothéliales durant la vie adulte afin d'établir des souris [Sirt6.sup.-/-]. Des souris [ApoE.sup.-/-]: [Sirt6.sup.-/-] et [ApoE.sup.-/-]: Sirt6Tg ont été utilisées dans leur recherche. Après 16 semaines d'une alimentation riche en gras, les souris développaient de façon évidente des plaques d'athérosclérose. L'ablation de Sirt6 exacerbait la progression de la plaque d'athérosclérose en ce qui concerne la taille et la stabilité. In vitro, les macrophages de souris RAW264.7 ont été traités avec des lipoprotéines de faible densité oxydées pendant 24 h pour simuler l'athérosclérose. Par ailleurs, la surexpression de Sirt6 accroissait de manière importante de flux autophagique des macrophages et inhibait l'apoptose des macrophages. De plus, la surexpression de Sirt6 inhibait l'expression des molécules d'adhérence cellulaire VCAM-1, ICAM-1 et P-sélectine, donnant lieu à une infiltration réduite des macrophages et des cellules spumeuses. En conclusion, cette étude propose une nouvelle stratégie à base mécanistique pour stimuler de manière thérapeutique la stabilité de la plaque d'athérosclérose. [Traduit par la Rédaction] Mots-clés : cellules spumeuses, obésité, lipoprotéines, biologie vasculaire, apolipoprotéines., Introduction Atherosclerosis is a chronic inflammatory disease and is characterized by lipid accumulation in the arterial walls (Martinet and De Meyer 2009). The majority of acute cardiovascular events such as [...]

As a device for cooling charged air before it enters the cylinder, the intercooler is an indispensable part of the regular operation of a booster diesel engine. To solve the problem of the insufficient cooling performance of an intercooler for a high-power supercharged diesel engine, in this study, the flow field in the intercooler is simulated using the computational fluid dynamics (CFD) model of porous media, and the performance data measured using the steady flow test bench are used to provide boundary conditions for the calculation. The effects of the charged air mass flow rate and the tube bundle's transverse spacing on the heat dissipation performance of the intercooler are analyzed and compared. The calculation results show that, under the condition of satisfying the regular operation of the diesel engine, the heat transfer coefficient of the intercooler heat dissipation belt increases with the increase in air mass flow and the spacing of cooling pipes, and the heat transfer coefficient can be increased by up to 57%. Still, excessive spacing of the cooling water pipes increases pressure loss in the charged air. Finally, the transverse spacing of the tube bundle is set to 17 mm, ensuring the pressure drop in the charged air, and the heat dissipation performance of the intercooler is increased by 6.04%. This paper provides a feasible solution for further optimizing the heat dissipation performance of intercoolers. Finally, grey correlation theory is used to study the correlation between air mass flow, cooling water pipe spacing, and intercooler heat dissipation performance. The correlation values are 0.8464 and 0.8497, respectively, indicating a significant relationship between air mass flow, cooling water pipe spacing, and intercooler heat dissipation performance. [ABSTRACT FROM AUTHOR]