Energetic landscape of alpha-lytic protease optimizes longevity through kinetic stability.

During the evolution of proteins the pressure to optimize biological activity is moderated by a need for efficient folding. For most proteins, this is accomplished through spontaneous folding to a thermodynamically stable and active native state. However, in the extracellular bacterial alpha-lytic protease (alphaLP) these two processes have become decoupled. The native state of alphaLP is thermodynamically unstable, and when denatured, requires millennia (t1/2 approximately 1,800 years) to refold. Folding is made possible by an attached folding catalyst, the pro-region, which is degraded on completion of folding, leaving alphaLP trapped in its native state by a large kinetic unfolding barrier (t1/2 approximately 1.2 years). alphaLP faces two very different folding landscapes: one in the presence of the pro-region controlling folding, and one in its absence restricting unfolding. Here we demonstrate that this separation of folding and unfolding pathways has removed constraints placed on the folding of thermodynamically stable proteins, and allowed the evolution of a native state having markedly reduced dynamic fluctuations. This, in turn, has led to a significant extension of the functional lifetime of alphaLP by the optimal suppression of proteolytic sensitivity.     

Comparative study of the karyotypes of two Egyptian species of bats,Taphozous perforatus andTaphozous nudiventris (Chiroptera: Mammalia)

A detailed karyotypic analysis of two Egyptian species of bats,Taphozous perforatus andTaphozous nudiventris, was made on the basis of conventional data and G-band patterns. No detectable karyotypic difference was found between the two species (2n=42, F.N. 64). By comparison of G-band patterns, some differences between the two species were seen in the corresponding autosomal pairs. These results are reported for the first time in Egypt.     

模式语义链元建模及其应用

大粒度的模型转换是模型驱动软件开发场景下的重要技术需求，仅通过定义通用模型转换语言不足以满足这一需求，其中一个原因是通用模型转换语言工作在特定建模语言的元模型层次而非一般设计意图层次上．文中提出一种模式语义链(PSL)元建模方法．通过重型扩展统一建模语言(UML)元模型以直接形式化描述可表达一般设计意图的模式，并应用UML动作语义和元模型继承实现模式自动生成及转换．该方法为实现一船设计意图层次上的大粒度模型转换提供了有效支持．     

大学英语教学低起点高目标的反思及应对策略

本文结合目前大学英语教学现状及社会对外语人才的要求，尝试着探讨大学英语教学低起点的缘由和高目标要求的应对策略。其意在为大学外语教学建立特殊的机制，充分发挥教育资源的整合效益，起到优化教学过程，达到最优化教学效果，最终最大限度地满足社会对各类外语人才的需要。     

论主导文化的艺术形态及其关于艺术的话语精神——以精神文明建设“五个一工程”评选中影视艺术获奖文本为例

文章把对主导文化艺术形态的分析和对精神文明建设“五个一工程”评选中电影艺术、电视剧艺术获奖文本的分析结合起来 ,梳理了主导文化在当代文化语境中关于艺术的几个主要方面的话语精神。     

Indoxyl derivatives of drug metabolites

Summary Indoxyl derivatives were detected as minor products among the urinary metabolites of two trial drugs, a benzodiazepine (GP 55 129) and a benzophenone (CGP 11 952). Their structures were elucidated by NMR and mass spectroscopy. Presumably, metabolites containing potential aldehyde functions react spontaneously with endogenous indoxyl. Such derivatives have not hitherto been encountered in drug metabolism.     

中国经济持续发展中的生态环境问题与逆转战略

本文应用生态学、经济学、市场学、环境学、灾害学的观点，分析了中国经济发展中环境的面临的主要问题和退化症结，根据市场经济发展的要求，提出了生态环境上合理、经济效益上合算、整治技术上先进的对策，为综合整治中国生态环境提供基本思路。     

粉粒状物料透气性系数的测定

对经过分级的六种均齐粉粒状物料进行透气性系数测定。结果表明:球形小米颗粒((?)_p=1.70mm),透气性系数K=1.191×10~(-9)m~2,在整个固定床范围内都符合达西定律;石灰石粉((?)_P=0.900mm),K=5.831×10~(-10)m~2。文中还讨论了达西定律的适用依据和透气性系数的影响因素。     

群与模范畴中的积和余积

积和余积是范畴学中的一对对偶概念，作为范畴学的一对基本概念自然在其具体对象中就会有所体现，以群，模为对象来讨论它们的积和余积。