流媒体技术在继续教育平台中的应用

在阐述了流媒体技术的基本原理的基础上，通过对主流技术的分析比较提出了以WindowsMedia为技术支撑，基于组播和点播的流媒体继续教育平台解决方案，并对资源的同步控制和安全策略作简要分析，实现一个功能丰富的继续教育平台．     

Cu（Ⅱ） effect on the conformation of regenerated silk fibroin in dilute aqueous solution

Much attention has been paid to the natural mechanism of silkworm spinning due to the impressive mechanical properties of the natural fibers. In this work, we studied the effect of Cu（Ⅱ） ions on the secondary structure of Bombyx mori regenerated silk fibroin （SF） in dilute solution by circular dichroism （CD）. The results indicate that a given amount of Cu（Ⅱ） induces the SF conformational transition from random coil to β-sheet, however, further addition of Cu（Ⅱ） is unfavorable for this conversion. Meanwhile, the conformational changes induced by Cu（Ⅱ） follow a nucleation-dependent aggregation mechanism, which is similar to that found in Prion protein （PrP） denaturation and Aβ-peptide aggregations, leading to the neurodegenerative disease. This work would help one understand further the natural spinning process of silkworm. Additionally, it would be significant for the study of the nervous system diseases, because silk fibroin, extracted in large amounts from Bombyx mori silkworm gland, could be a proper model to study PrP denaturation and Aβ-peptide aggregations.     

高精度步进压印机热误差的建模分析

为了消除由紫外光曝光所引起的步进压印机的热误差，以提高压印机的套刻对准精度，运用逐步回归分析法选取了压印机上温度测量点的数量，将压印机上布置的温度传感器从15个减少到6个，并建立了压印机温度测量关键点处的温度与压头在x、z方向热误差关系的数学模型．实验结果与模型计算结果的对比分析表明，模型的热误差预测精度在x方向可以达到899／6，而在z方向可以达到939／6．应用表明，该方法是一种在压印机热误差建模中选择温度测量关键点的有效方法，可避免热误差建模过程中的变量耦合问题，从而提高了模型的精确性．     

仿射Weyl群(E～)6的a值5的左胞腔

Coxeter群的胞腔是1979年Kazhdan和Lusztig中定义的，这些胞腔理论在代数群的表示理论中发挥了重要的作用。对一些特殊的情况，胞腔的分类已经明确地给出了，例如，对于秩为2的群参见，对于An^-参见，对于a值4的典范型和或参见.本文利用时俭益的运算算法给出了仿射Weyl群E6^-的a值等于5的所有左胞腔。     

A new indolic antiauxin, α-(5,7-dichloroindole-3-)isobutyric acid: its chemical synthesis and biological activity

Summary A new potent antiauxin, -(5,7-dichloroindole-3-)isobutyric acid has been synthesized and shown to inhibit auxin-mediated elongation ofAvena coleoptiles and to stimulate root growth of rice seedlings. Its activity is stronger than -(p-chlorophenoxy)isobutyric acid and is comparable to that of 2,3,5-triiodobenzoic acid, which are typical antiauxins.     

Proopiomelanocortin expression in the skin during induced hair growth in mice

We demonstrate for the first time a hair cycle-dependent gene and protein expression of proopiomelanocortin in mouse skin in vivo. Northern blot detected POMC mRNA with an apparent size of 0.9 kb in anagen but not telogen skin. Western blot emphasized a specific protein of 30–33 kDa recognized by anti -endorphin in late but not early anagen or telogen skin. By immunocytochemistry, -endorphin antigen was localized in the sebaceous gland in a hair cycle dependent manner.     

In vitro protein synthesis and α amylase activity in F cells from hepatopancreas ofPalaemon serratus (Crustacea; Decapoda)

In crustaceans, all the steps in the assimilation of food take place in the hepatopancreas. To facilitate the study of this organ, a method for the dissociation of cell types was developed. The hepatopancreas of the prawnPalaemon serratus was mechanically dissociated and the cells separated by Percoll density-gradient centrifugation. The E and R cells had similar densities of around 1.05 g/ml. The F cells were separated into two distinct fractions with densities of 1.075 and 1.082 g/ml. The B cells sedimented at a density of 1.12 g/ml. The ratio between the two populations of F cells was found to vary during the intermolt cycle while B cells disappeared after the molt. When the density gradient fractions were incubated with³H-leucine, incorporation was highest in the F cell fractions. Measurements of -amylase activity, indicated that the two populations of F cells may be derived from the same cell type.     

A new semisynthetic ergot peptide alkaloid: DCN 203-922

Summary We report the synthesis, stereochemistry and preliminary pharmacological evaluation of DCN 203-922, a novel ergot alkaloid of the cyclol type, which contains in its peptide moiety the uncommon amino acid L-allo-isoleucine.Part of this paper was reported by this author at the Herbstversammlung der Schweizerischen Chemischen Gesellschaft, Bern, in October 1986.