Cross-functional analysis of the Microviridae internal scaffolding protein

The assembly of the viral structural proteins into infectious virions is often mediated by scaffolding proteins. These proteins are transiently associated with morphogenetic intermediates but not found in the mature particle. The genes encoding three Microviridae (phiX174, G4 and alpha3) internal scaffolding proteins (B proteins) have been cloned, expressed in vivo and assayed for the ability to complement null mutations of different Microviridae species. Despite divergence as great as 70% in amino acid sequence over the aligned length, cross-complementation was observed, indicating that these proteins are capable of directing the assembly of foreign structural proteins into infectious particles. These results suggest that the Microviridae internal scaffolding proteins may be inherently flexible. There was one condition in which a B protein could not cross-function. The phiX174 B protein cannot productively direct the assembly of the G4 capsid at temperatures above 21 degreesC. Under these conditions, assembly is arrested early in the morphogenetic pathway, before the first B protein mediated reaction. Two G4 mutants, which can productively utilize the phiX174 B protein at elevated temperatures, were isolated. Both mutations confer amino acid substitutions in the viral coat protein but differ in their relative abilities to utilize the foreign scaffolding protein. The more efficient substitution is located in a region where coat-scaffolding interactions have been observed in the atomic structure and may emphasize the importance of interactions in this region.     

Reduced immunotoxicity and preservation of antibacterial activity in a releasable side-chain carbapenem antibiotic

A carbapenem antibiotic, L-786,392, was designed so that the side chain that provides high-affinity binding to the penicillin-binding proteins responsible for bacterial resistance was also the structural basis for ameliorating immunopathology. Expulsion of the side chain upon opening of the beta-lactam ring retained antibacterial activity while safely expelling the immunodominant epitope. L-786,392 was well tolerated in animal safety studies and had significant in vitro and in vivo activities against methicillin- and vancomycin-resistant Staphylococci and vancomycin-resistant Enterococci.     

Exercise--it''s never too late: the strong-for-life program

Design and associated good practices are described for a modular glovebox connector to improve control of radioactive and chemically toxic materials. The connector consists of an anodized aluminum circular port with a mating spacer, gaskets, and retaining rings for joining two parallel ends of commercially available or custom-manufactured glovebox enclosures. Use of the connector allows multiple gloveboxes to be quickly assembled or reconfigured in functional units. Connector dimensions can be scaled to meet operational requirements for access between gloveboxes. Options for construction materials are discussed, along with recommendations for installation of the connector in new or retrofitted systems. Associated good practices include application of surface coatings and caulking, use of disposable glovebags, and proper selection and protection of gasket and glove materials. Use of the connector at an inhalation toxicology research facility has reduced the time and expense required to reconfigure equipment for changing operational requirements, the dispersion of contamination during reconfigurations, and the need for decommissioning and disposal of contaminated enclosures.     

Empirical foundations for writing in prevention and psychotherapy: mental and physical health outcomes

The use of writing, alone or in conjunction with traditional psychotherapy, has increased substantially in recent years. The most widespread use of writing has been for single-shot ad hoc purposes or to log behavior. The purpose of this review is to summarize a decade of research demonstrating the efficacy of writing about past traumatic experiences on mental and physical health outcomes. It is widely acknowledged in our culture that putting upsetting experiences into words can be healthy. Research from several domains indicates that talking with friends, confiding to a therapist, praying, and even writing about one's thoughts and feelings can be physically and mentally beneficial. This review highlights advances in written disclosure that determine some therapeutic outcomes. In addition, we attempt to explore the mechanisms that predict improved psychological and physical health. Finally, limitations of previous studies are highlighted, and suggestions for future research and application are made.     

纤维素负载金属基催化体系在有机反应中的研究进展EI北大核心CSCD

金属基催化剂现已成为催化领域的主流催化剂,但其存在难以分离循环使用、催化剂遗留、成本较高、催化剂与底物不稳定性等问题,采用高分子载体进行负载是解决以上问题的一种有效方法。纤维素是地球最丰富的绿色高分子,作为催化剂载体具有来源广泛、可生物降解、无毒、良好的生物相容性的优异特点,且分子结构上具有大量的羟基易改性、可通过多种方式负载金属催化剂。因此,本文综述了纤维素作为载体,负载零价金属纳米粒子、非零价金属基催化剂的进展,以及对负载后的催化体系在氧化还原反应、Heck反应、Suzuki反应等反应中的催化活性进行概述;并通过对比该体系中载体-金属等之间的作用机理,阐述了不同负载方式之间的协同作用,以及催化活性的差异性。     

增材用铝粉表面的包覆改性研究

为减少铝粉在光固化树脂中的沉降,使其适用于光固化增材制造,使用不同表面活性剂对铝粉进行预处理,增强铝粉表面对有机物的亲和性;利用乳液聚合法使单体聚合在铝粉表面形成一层有机物薄膜,研究几种单体对铝粉包覆性能的影响,利用可见光分光光度计、傅里叶红外光谱仪表征其包覆性能。结果表明:使用十二烷基硫酸钠(K12)预处理的铝粉在光固化树脂中分散性最好,透光率为11%,分散1 h后透光率变化不大;使用苯乙烯（St）+丙烯酸丁酯(BA)、丙烯酸(AA)+丙烯酸丁酯(BA)二元聚合包覆的铝粉在树脂中静置1 h,未发现明显沉降;红外光谱图显示,两组配方中的铝粉表面存在单体聚合产物。     

油气悬架零部件正态模糊可靠度计算

从强度安全性的角度出发，综合运用了概率密度函数联合积分法与功能密度函数积分法，整理并推导了油气悬架零部件的模糊可靠度计算公式，即应力、强度都为正态分布，隶属度函数为抛物线分布时的模糊可靠度计算公式；通过VB编程实现数值解的计算，根据输入的原始数据与积分区间的特点进行积分变换，然后利用中点公式积分法与龙贝格求积法进行积分计算.本程序可直接应用于设计计算中，以提高油气悬架的设计水平.     

大面积光学多层膜玻璃

随着磁控溅射技术的不断进步,大面积光学多层膜玻璃也日渐发展,广泛地应用于建筑、汽车、平板显示等行业。对几种大面积光学多层膜玻璃的原理、应用以及制备技术分别作了简要介绍及评述。