Heparan sulfate-protein interactions: therapeutic potential through structure-function insights

Heparin and the related glycosaminoglycan, heparan sulfate, bind a myriad of proteins. The structural diversity of heparin and heparan sulfates is enormous, but differences in the conformational flexibility of the monosaccharide constituents add extra complexity and may influence protein binding. Silencing genes for heparin/ heparan sulfate biosynthetic enzymes profoundly affects mammalian development. Thus, altering the structure of heparan sulfate chains can alter protein binding and embryo development. Different heparan sulfate structures are located in particular tissue sites, and these structures are recognised by different sets of proteins. Regulation of certain heparan sulfate-protein interactions by pH or cations is described. Heparin/heparan sulfate structures are viewed as potential therapeutics for a variety of diseases. An understanding at the molecular and functional levels of the specificity and affinity of heparan sulfate-protein interactions is crucial for designing heparin-inspired drugs. How the development of synthesis techniques is facilitating structure-function analyses and drug development is discussed.Received 6 July 2004; received after revision 16 September 2004; accepted 28 September 2004     

Moisture transport source／sink structure of the Meiyu rain belt along the Yangtze River valley

Based on the analyses of the moisture transport structure in the whole layer of the troposphere along the Yangtze River valley during draught/flood years using the NCEP reanalysis data, this paper reveals that there exists a key region with a “Large Triangle” shape of transporting moisture for the Tibetan Plateau to Meiyu Belt and its“source/sink” structure; discloses that the interannual variation of the whole budget of inflow and outflow of moisture through the boundaries of a “Large Triangle” key region has the in-phase characteristic. Then a moisture transport structure over the skirt of the plateau and a conceptual model on the “transfer post” of moisture transport in the area of the South China Sea-Tibetan Plateau-Yangtze River valley in summer are put forward in this paper: the anti-phase feature of whole layer moisture transport flow patterns of Yangtze River valley during drought/flooding years is exhibited using the computational scheme of whole layer moisture transport correlation vector fields; a comprehensive dynamic model and its physical diagram of the teleconnection source/sink structure of the moisture transport of the Meiyu rain belt have been made. It shows that the moisture transfer effect over the skirt of the plateau from the ocean (Indian Ocean, South China Sea and west North Pacific) led to a moisture confluence belt in the Yangtze River valley and the teleconnection moisture transport source/sink structure over the “Large Triangle” shape area in flooding years.     

应用Velocity和J2EE构建基于WEB的远程教育管理系统

描述了一种基于WEB远程教育管理系统的设计与实现方案 ,底层采用了数据仓库技术 ,使教学者能够进行复杂的教务管理 ,并能引导不同学生进入不同学习过程 .详细讨论了远程教育管理系统基于底层数据库的决策支持系统和基于WEB的远程教育管理系统具体实现方法和技术     

FVM结合PDF方法研究湍流射流火焰中的辐射换热

为了考察湍流燃烧过程中的辐射换热效应，用有限体积和概率密度函数输运方程求解相结合的方法模拟了湍流自由射流火焰中的辐射换热，并对湍流辐射交互作用进行研究．计算结果表明，辐射换热作用将使火焰的温度有所降低；湍流辐射交互作用使辐射换热有较大幅度的增强，需要在辐射换热计算中予以考虑．     

细粒浮选体系中粗粒效应理论与应用

本文研究了紊流条件下粗粒与细粒颗粒群间的相互作用,提出“粗粒效应”理论,包括三种作用机理:粗粒的载体作用,以漩涡微尺度λ_0为理论判据;粗粒的助凝作用,以颗粒雷诺数Re_p为理论判据;粗粒的中介作用,以裂解频率f_B为理论判据。λ_0值对应于最佳载体粒度,Re_p大,助凝作用大,f_B大,裂解作用大。     

Cs_2NaYbBr_6体系中 Yb~(3+)的能级计算

本文用等价算符法和不可约张量法,考虑~F_(7/2)与~2P_(5/2)的晶场相互作用,对Cs_2NaYbBr_6体系(O_h)中Yb~(3+)的实验能级进行了拟合计算,得到到晶场参数为B_(40)=1416 cm~(-1)、B_(60)=46cm~(-1),旋轨耦合参数ζ=2871 cm~(-1).同时,对计算结果进行了讨论.     

AES与计算机模拟技术研究Ce-P晶界共偏聚

用俄歇能谱分析(AES),结合计算机模拟技术研究稀土元素Ce与杂质元素P在铁中的晶界共偏聚规律。实验结果表明,在P含量较低的情况下,Ce有抑制P晶界偏聚的作用,而当P含量较高时,Ce却有促进P晶界偏聚的作用。计算机模拟结果表明,当晶界上P的偏聚量不同时,Ce原子与P原子在晶界形成的偏聚结构不同。Ce对P在晶界偏聚作用的改变主要是因为晶界偏聚的P浓度不同使Ce与P晶界共偏聚所形成的最低能量结构改变。     

SU(8)禁闭弱作用手征亚夸克大统一模型

本文考虑到手征性要求,基于文献[2]的讨论,以[su(3)×su(2)]_Hc作为超色群,弱相互作用作为超色力的剩余效应,构造了一个禁闭弱作用手征亚夸克大统一模型su(8),并可得到三代费米子。     

基于多进制频移键控调制的水声远程信息传输技术研究

研究了一种基于多进制频移键控(MFSK)调制的水声远程信息传输技术，给出了通过谱分析进行频域解调的方法．即对于单个码元周期内的接收信号，计算其四阶累积量对角切片的傅立叶谱，将谱峰处的频率值作为载频的估计，根据载频与传输信息的对应关系进行解调．初步的海上试验结果表明，该技术可以实现80km距离、4bit／s数据率的信息可靠传输．