数学编程中的分解技术 工程和科学应用

优化已经明显地主导工程系统的设计、计划、运行和控制，本书论述有可分解结构的优化问题，这种可分解的优化问题在工程和科学应用中是普遍存在的，书中考虑既有复杂约束又有复杂变量的优化问题，分析有或没有整数量的线性和非线性问题，所分析的分解技术包括Dantzig．Wolf、Benders、拉格朗日松弛、增大的拉格朗日分解和其他方法，     

Cell-cycle checkpoints and cancer

All life on earth must cope with constant exposure to DNA-damaging agents such as the Sun's radiation. Highly conserved DNA-repair and cell-cycle checkpoint pathways allow cells to deal with both endogenous and exogenous sources of DNA damage. How much an individual is exposed to these agents and how their cells respond to DNA damage are critical determinants of whether that individual will develop cancer. These cellular responses are also important for determining toxicities and responses to current cancer therapies, most of which target the DNA.     

Ultra-remote stereocontrol by conformational communication of information along a carbon chain

Many receptors and allosteric proteins function through binding of a molecule to induce a conformational change, which then influences a remote active site. In synthetic systems, comparable intramolecular information transfer can be effected by using the shape of one part of a molecule to control the stereoselectivity of reactions occurring some distance away. However, the need for direct communication with the reaction site usually limits such remote stereocontrol to distances of not more than about five bond lengths. Cyclic structures overcome this problem by allowing the controlling centre and the reaction site to approach each other, but the information transfer spans only short absolute distances. Truly remote stereocontrol can, however, be achieved with rigid compounds containing amide groups: the conformation of the amides can be controlled by stereogenic centres and responds to that of neighbouring amide groups and in turn influences stereoselective reactions. This strategy has allowed remote stereocontrol spanning 8 (ref. 11) or 9 (ref. 12) bonds. Here we demonstrate stereocontrol over a reaction taking place more than 20 bond lengths from the controlling centre, corresponding to a linear distance of over 2.5 nm. This transmission of information, achieved by conformational changes relayed through the molecule, provides a chemical model of allostery and might serve as a molecular mechanism for communicating and processing information.     

Neurolinguistics: structural plasticity in the bilingual brain

Humans have a unique ability to learn more than one language--a skill that is thought to be mediated by functional (rather than structural) plastic changes in the brain. Here we show that learning a second language increases the density of grey matter in the left inferior parietal cortex and that the degree of structural reorganization in this region is modulated by the proficiency attained and the age at acquisition. This relation between grey-matter density and performance may represent a general principle of brain organization.     

柴达木山花岗岩锆石SHRIMP定年

锆石SHRIMP定年研究表明,祁连南缘柴达木山花岗岩与超高压榴辉岩是构造演化过程中不同阶段形成的,即加里东早期,该区存在洋壳－陆壳碰撞,形成榴辉岩;加里东晚期,存在陆壳－陆壳的碰撞,形成了该花岗岩体。该岩体的SHRIMP年龄为446Ma。