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91.
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Silicon - A novel low-loss and good-robustness silicon-on-insulator lateral insulated gate bipolar transistor (LIGBT) is proposed and investigated by simulation for the first time. The device is... 相似文献
93.
Metal Science and Heat Treatment - The influence of the temperature of heating for quenching and subsequent heating for redistribution of carbon between martensite and retained austenite... 相似文献
94.
Hoseinie S. H. Ataei M. Mikaeil R. 《Bulletin of Engineering Geology and the Environment》2019,78(3):1443-1449
Bulletin of Engineering Geology and the Environment - Quantifying the rock microfabric is one of the most important research interests and challenges in the field of rock drilling and excavation.... 相似文献
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Thickness and scratch resistance of adsorbed film formed by triblock symmetrical copolymer solutions
The thickness and scratch resistance of adsorbed films formed on mild steel samples (MS1020), which have been immersed in water copolymer solutions, are reported. The effects of bulk temperature and the copolymer structures, normal, poly(ethylene oxide)m‐poly(propylene oxide)n‐poly(ethylene oxide)m, and reverse, poly(propylene oxide)n‐poly(ethylene oxide)m‐poly(propylene oxide)n, are elucidated. The films' thicknesses are independent of structure but not of temperature. The adsorbed films of above cloud point solutions are thicker than below cloud point. However, nanoscratch experiments carried out to measure the scratch resistance of the films reveal that despite of thicker film formed by above cloud point solutions, it is relatively more prone to being detached than the thinner films of below cloud point solutions. The effect of extreme pressure additive, alkyl phosphate ester (APE), is also investigated suggesting the normal copolymer has comparable scratch resistance with APE when used at below the cloud point. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Vijay H. Masand Sami A. Al-Hussain Mithilesh M. Rathore Sumer D. Thakur Siddhartha Akasapu Abdul Samad Aamal A. Al-Mutairi Magdi E. A. Zaki 《International journal of molecular sciences》2022,23(23)
Aurora kinase B (AKB) is a crucial signaling kinase with an important role in cell division. Therefore, inhibition of AKB is an attractive approach to the treatment of cancer. In the present work, extensive quantitative structure–activity relationships (QSAR) analysis has been performed using a set of 561 structurally diverse aurora kinase B inhibitors. The Organization for Economic Cooperation and Development (OECD) guidelines were used to develop a QSAR model that has high statistical performance (R2tr = 0.815, Q2LMO = 0.808, R2ex = 0.814, CCCex = 0.899). The seven-variable-based newly developed QSAR model has an excellent balance of external predictive ability (Predictive QSAR) and mechanistic interpretation (Mechanistic QSAR). The QSAR analysis successfully identifies not only the visible pharmacophoric features but also the hidden features. The analysis indicates that the lipophilic and polar groups—especially the H-bond capable groups—must be present at a specific distance from each other. Moreover, the ring nitrogen and ring carbon atoms play important roles in determining the inhibitory activity for AKB. The analysis effectively captures reported as well as unreported pharmacophoric features. The results of the present analysis are also supported by the reported crystal structures of inhibitors bound to AKB. 相似文献
100.
Hlne Holota Anglique De Haze Emmanuelle Martinot Melusine Monrose Jean-Paul Saru Franoise Caira Claude Beaudoin David H. Volle 《International journal of molecular sciences》2022,23(23)
Understanding the regulation of the testicular endocrine function leading to testosterone production is a major objective as the alteration of endocrine function is associated with the development of many diseases such as infertility. In the last decades, it has been demonstrated that several endogenous molecules regulate the steroidogenic pathway. Among them, bile acids have recently emerged as local regulators of testicular physiology and particularly endocrine function. Bile acids act through the nuclear receptor FXRα (Farnesoid-X-receptor alpha; NR1H4) and the G-protein-coupled bile acid receptor (GPBAR-1; TGR5). While FXRα has been demonstrated to regulate testosterone synthesis within Leydig cells, no data are available regarding TGR5. Here, we investigated the potential role of TGR5 within Leydig cells using cell culture approaches combined with pharmacological exposure to the TGR5 agonist INT-777. The data show that activation of TGR5 results in a decrease in testosterone levels. TGR5 acts through the PKA pathway to regulate steroidogenesis. In addition, our data show that TGR5 activation leads to an increase in cholesterol ester levels. This suggests that altered lipid homeostasis may be a mechanism explaining the TGR5-induced decrease in testosterone levels. In conclusion, the present work highlights the impact of the TGR5 signaling pathway on testosterone production and reinforces the links between bile acid signaling pathways and the testicular endocrine function. The testicular bile acid pathways need to be further explored to increase our knowledge of pathologies associated with impaired testicular endocrine function, such as fertility disorders. 相似文献