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Previous studies suggest that perceived stigmatization of sexual minority status, ethnicity, and age are associated with negative mental health outcomes, and other studies suggest that coping styles may influence these outcomes. However, no studies have examined these relationships among gay men of varying ethnicities and age groups. Three hundred eighty-three Black and White, younger, middle-aged, and older adult gay men completed measures of perceived stigmatization, coping style, and mental health outcomes. Black older adult gay men reported significantly higher levels of perceived ageism than the older White group, significantly higher levels of perceived racism than the younger Black group, significantly higher levels of homonegativity than the younger Black and the White groups, and were more likely to use disengaged coping styles than White gay men. However, Black older adult gay men did not experience significantly higher levels of negative mental health outcomes. Results suggest that further research should examine how older Black gay men, who perceive higher levels of stigma while reporting greater use of less effective coping styles, do not appear to be experiencing more negative mental health outcomes as a result. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We report here our preliminary investigations on the mechanism of α-TTP-mediated ligand transfer as assessed using fluorescence resonance energy transfer (FRET) assays. These assays monitor the movement of the model α-tocopherol fluorescent derivative ((R)-2,5,7,8-tetramethyl-chroman-2-[9-(7-nitro-benzo[1,2,5]oxadiazol-4-yl amino)-nonyl]-chroman-6-ol; NBD-Toc) from protein to acceptor vesicles containing the fluorescence quencher TRITC-PE. We have found that α-TTP utilizes a collisional mechanism of ligand transfer requiring direct protein–membrane contact, that rates of ligand transfer are greater to more highly curved lipid vesicles, and that such rates are insensitive to the presence of anionic phospholipids in the acceptor membrane. These results point to hydrophobic features of α-TTP dominating the binding energy between protein and membrane. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. An erratum to this article can be found at  相似文献   
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编者按 一直以来,CIO被认为是企业信息化建设的灵魂人物.但在最近,业界对CIO的看法有了改变.一是部分企业(如英国电信)完全取消了CIO岗位;另外,Gartner在一份调查报告中也指出,全球约有2/3的CIO担心被公司解职.这说明,CIO对自己的职位前景不感光明.那么,那些看空CIO的人究竟持有怎样的观点,CIO一职真可能被其他角色替代吗?  相似文献   
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In this paper, an approach to simulating magnetohydrodynamic (MHD) flows based on the lattice Boltzmann method (LBM) is presented. The dynamics of the flow are simulated using a so-called multiple relaxation time (MRT) lattice Boltzmann equation (LBE), in which a source term is included for the Lorentz force. The evolution of the magnetic induction is represented by introducing a vector distribution function and then solving an appropriate lattice kinetic equation for this function. The solution of both distribution functions are obtained through a simple, explicit, and computationally efficient stream-and-collide procedure. The use of the MRT collision term enhances the numerical stability over that of a single relaxation time approach. To apply the methodology to solving practical problems, a new extrapolation-based method for imposing magnetic boundary conditions is introduced and a technique for simulating steady-state flows with low magnetic Prandtl number is developed. In order to resolve thin layers near the walls arising in the presence of high magnetic fields, a non-uniform gridding strategy is introduced through an interpolated-streaming step applied to both distribution functions. These advances are particularly important for applications in fusion engineering where liquid metal flows with low magnetic Prandtl numbers and high Hartmann numbers are introduced. A number of MHD benchmark problems, under various physical and geometrical conditions are presented, including 3-D MHD lid driven cavity flow, high Hartmann number flows and turbulent MHD flows, with good agreement with prior data. Due to the local nature of the method, the LBM also demonstrated excellent performance on parallel machines, with almost linear scaling up to 128 processors for a MHD flow problem.  相似文献   
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