Structure Characterization of Silk Fibroin Crystalline Domain Polypeptides Expressed in Escherichia coli

The molecular conformations of four silk fibroin crystalline analogues [GAGAG-X] 16(G,Gly;A,Ala;X=Ala,Ser,Tyr or Val,designated eGA,eGS,eGY or eGV),carried out using molecular design and expressed by Escherichia coil(E.coli),were evaluated by Raman spectra analysis.The abilities of forming β-sheet structure were determined by thioflavin T(ThT) fluorescence spectra analysis.In terms of molecular conformation,except eGY that could not form significant typical molecular conformation,eGS and eGV were mainly com...     

The Relationship between the Mechanical Properties of Pure Silk Fabrics and Dress Performance

In this paper, the relationship between mechanical properties of 30 pieces of pure silk fabrics and the dress performance has been analyzed. With the methods of multifactor linear step regression and discrimination analysis, the judgment and prediction model of the performance have been established.     

Cell biology: nondisjunction, aneuploidy and tetraploidy

One simple, widely accepted mechanism for generating an aberrant chromosome number, or aneuploidy, is through nondisjunction--a chromosome distribution error that occurs during mitosis when both copies of a duplicated chromosome are deposited into one daughter cell and none into the other. Shi and King challenge this view, concluding that nondisjunction does not yield aneuploid cells directly, but instead gives rise to tetraploid cells that may subsequently become aneuploid through further division. Here we show that the direct result of chromosome nondisjunction is gain or loss of a single chromosome, which results in near-diploid aneuploidy, not tetraploidy. We suggest that chromatin trapped in the cytokinetic cleavage furrow is the more likely reason for furrow regression and tetraploidization.     

Chimpanzees are indifferent to the welfare of unrelated group members

Humans are an unusually prosocial species-we vote, give blood, recycle, give tithes and punish violators of social norms. Experimental evidence indicates that people willingly incur costs to help strangers in anonymous one-shot interactions, and that altruistic behaviour is motivated, at least in part, by empathy and concern for the welfare of others (hereafter referred to as other-regarding preferences). In contrast, cooperative behaviour in non-human primates is mainly limited to kin and reciprocating partners, and is virtually never extended to unfamiliar individuals. Here we present experimental tests of the existence of other-regarding preferences in non-human primates, and show that chimpanzees (Pan troglodytes) do not take advantage of opportunities to deliver benefits to familiar individuals at no material cost to themselves, suggesting that chimpanzee behaviour is not motivated by other-regarding preferences. Chimpanzees are among the primates most likely to demonstrate prosocial behaviours. They participate in a variety of collective activities, including territorial patrols, coalitionary aggression, cooperative hunting, food sharing and joint mate guarding. Consolation of victims of aggression and anecdotal accounts of solicitous treatment of injured individuals suggest that chimpanzees may feel empathy. Chimpanzees sometimes reject exchanges in which they receive less valuable rewards than others, which may be one element of a 'sense of fairness', but there is no evidence that they are averse to interactions in which they benefit more than others.     

美亚丝织厂的每周新产品

美亚丝织厂每逢星期一在报纸上发布新产品广告,这种高速度开发新产品、迎合市场需要的做法,曾轰动国内丝绸市场。文中从5个方面揭示了美亚丝织厂研制新品种的做法,分析了自建厂以来到新中国成立时的20多年中所开发的1246个品号的产品类型和特性。     

服装结构设计CAD系统开发

本文对计算机辅助服装结构设计系统的设计思想与实现方法进行了探讨.提出将结构设计过程分作结构线设计和外形线设计两步完成,用导出关键参量计算模型的方法解决结构线设计中的经验估值问题;用图形变换的方法解决外形线设计中的"临摹"手法,从而较好地处理了设计师进行结构设计时所表现出的"活"的方面.以此为基础,在IBM PC/XT机上研制初步的服装结构设计系统.     

Protease Selection and Technology Optimization in Biofinish of Wool

A process for the shrink - resist treatment of wool by protease with a hydrogen peroxide pretreatment (the Perzym process) has been studied. A protease, selected from several commercial proteases, has been found having higher activity in shrink - resist treatment, and its optimum technological conditions, which confer wool better shrinkproofing and less strength and elongation loss, have been obtained by an orthogonal factorial design approach. The study shows that it is possible for the wool to be conferred excellent machine washability by the Perzym process.     

Research on the Dyeing and Finishing Properties of Wool Treated with Chitosan

The dyeing and finishing properties of wool treated with chitosan were studied. It was shown that chitosan can be absorbed by wool in an acetic acid bath, both dyeing rate and equilibrium dye uptake of wool treated with chitosan increase in a wide pH range from strong acid to neutral conditions. This work also indicated that chitosan could be used to achieve feltproofing of wool.