韶关市人口现状与高等教育大众化研究

通过对韶关市第五次人口普查中总体人口、行业人口、职业人口受教育程度等资料情况的分析,探讨韶关市实施高教大众化的途径.     

线虫动物门、腹毛动物门及轮虫动物门间的系统学研究

用支序分析方法对线虫动物门、腹毛动物门和轮虫动物门三者之间的系统学进行了分析，结论是三者为一单系群，其中腹毛动物门和轮虫动物门为一对姐妹群，线虫动物门则是三者的共同祖先较早地分出的另一支。由此我们认为，应将这三者合并为一新门合胞体动物门（Syncytia)，原来各门分别降为线虫纲、腹毛纲和轮虫纲；原腔动物门这一分类阶元应予废弃。     

求解方程近似解的改进双曲线型迭代算法

应用双曲线逼近法,在分析了迭代算法思想的基础上,结合过程模拟与系统仿真的实际,推导出求解方程f(x)=0近似根新型迭代算法,并给出了迭代格式和计算方法.计算结果表明,用此算法求解方程的根,收敛速度及稳定性均好于割线法,初值选取范围比牛顿法和割线法宽.此算法的提出对于方程求根的理论分析和工程应用都有十分重要的意义.     

牛奶中蛋白质含量的示波滴定法

研究了牛奶中蛋白质含量的示波滴定法。样品用H2SO4－Na2SO4-CuSO4消化处理，N以NH4^ 的形式存在于试液中，用过量四苯硼钠沉淀铵，沉淀过滤，过量的四苯硼钠用氯化四乙基铵标准溶液返滴定，以四苯硼钠切口消失为终点，计算出氮含量，再换算为蛋白质含量。本方法终点变化敏锐，不外加指示剂，与通用的标准分析方法相比较，操作简便、快速，测定结果准确可靠，所用分析试剂无毒。     

试论城市绿化在建设生态城市中的作用

阐述了城市绿化在建设生态城市中的作用，提出了加快城市绿化建设步伐的措施。     

SO_2对NO催化氧化过程的影响 I.载体的作用

研究了载体在 SO2 影响 NO催化氧化过程中的作用 ,考察了反应温度为 42 3 K时 ,γ-Al2 O3、Zr O2 、Ti O2 和 Si O2 4种载体及其负载的 Pt催化剂对 NO的氧化性能 ,与 SO2 存在下的 NO反应活性相比 ,只有 γ-Al2 O3及其负载的 Pt催化剂上存在 SO2 促进 NO氧化的现象。运用 BET、XRD、IR及固体酸度测定等多种表征手段 ,对不同载体在反应前后的化学结构和表面性质进行了分析 ,并与反应过程相联系 ,证实 SO2 的吸附改变了γ-Al2 O3的表面结构 ,有利于产物 NO2 的脱附 ;而对 SO2 吸附能力较弱的其他载体或催化剂 ,SO2 的影响则不同     

A Web-Based Integrated Intelligent System for Sensory Fabric Hand Evaluation

IntroductionInmanyindustrialsectorssuchasfood,cosmetic,medical,chemical,andtextile,sensoryevaluationiswidelyusedfordeterminingthequalityofendproducts,solvingconflictsbetweensuppliersandproducers,developingnewproducts,andexploitingnewmarketadaptedtotheconsumerspreference[1].Sensoryevaluationofindustrialproductsleadstoasetoflinguistictermsstronglyrelatedtoconsumerpreferencebutdifficulttobenormalizedduetotheiruncertaintyandimprecision.Assuch,thisevaluationrestrictsthescientificunderstandingofprod…     

富硒大豆低聚肽的生理功能及应用前景

硒是重要的生命微量营养元素之一，通过大豆富集硒并转化为大豆硒蛋白，再经酶解后分离纯化便得到富硒大豆低聚肽，它具有独特的理化特性和生理功能，在营养学上有着许多优点，在食品、化工、饲料以及医药上均具有十分广阔的应用前景．     

Interleukin-4 mediates CD8 induction on human CD4+ T-cell clones

CD4 and CD8 antigens are simultaneously expressed on most of the cortical thymocytes, that weakly express the T-cell antigen receptor(TCR)/CD3 complex. Mature peripheral T cells, however, strongly express the TCR complex and are positive for either CD4 or CD8. Nevertheless, a small percentage of peripheral CD3+ T cells express CD4 and CD8 simultaneously. These mature, double positive cells could be intermediates between CD4+CD8+ thymocytes and mature, single positive T cells, or they may originate from single positive T cells that acquire either CD4 or CD8. Here we report that activation and culturing of cloned CD4+ T cells in interleukin-4 (IL-4), results in the acquisition of CD8 due to its de novo synthesis. The IL-4-induced co-expression of CD8 on CD4+ T cells is reversible, in that CD8 disappeared from double positive T-cell clones isolated in IL-4, when they were cultured in IL-2. CD8 induced by IL-4 can be functional as a monoclonal antibody to CD8 inhibited anti-CD3-mediated cytotoxicity by a double positive T-cell clone.     

Regulatory properties of LFA-1 alpha and beta chains in human T-lymphocyte activation

Lymphocyte function-associated antigen-1 (LFA-1) is a heterodimer composed of an alpha and beta chain that is expressed on the surface of most leukocytes and is an essential molecule for adhesion reactions between cells participating in the immune response. A putative ligand for LFA-1 is the intercellular adhesion molecule ICAM-1 (refs 3-5). Leukocyte adhesion abnormality is found in patients with LFA-1 deficiency. It is not clear whether binding of ligand to the LFA-1 molecule merely spatially orientates cells towards each other or can also induce signals that regulate cell activation and differentiation. We have recently developed a T-cell proliferation assay which uses immobilized anti-CD3 monoclonal antibodies as stimulant and is independent of LFA-1-mediated cellular adhesion. As there is no interference by anti-LFA-1 monoclonal antibodies with the adhesion-dependent activation steps, this T-cell activation system allows us to investigate whether transmembrane signals are induced by binding of ligand to LFA-1 on T cells. Our data indicate that binding of ligand to LFA-1 results in the transduction of regulatory signal across the plasma membrane, rather like other molecules (CD2, CD4, CD8) (refs 8-11) with signal-modifying properties involved in the adhesion of T cells to target/stimulator cells. Indeed, adhesion molecules might generally be important in signal transduction, even in cells not belonging to the immune system.