我国建筑结构质量现状分析

结合我国当前建筑结构质量状况 ,分析了质量事故发生的时间和原因 ,指出了改善、控制和维修等措施     

政治经济学课程教学改革的思考

在师范院校政教系政治经济学既是政治理论课又是专业基础课。搞好政治经济学的教学,不仅对于学生学习好后续课程具有重要的基础性意义,而且对于培养学生的理论兴趣、科学精神和科学方法、创新精神和实践能力也具有十分重要的作用。因此,作为政治经济学课教师必须不断改革,在教学内容、方法、手段上创新,大胆探索,勇于实践,才能使政治经济学的教学更加适应新世纪人才培养的需要。     

云南城市化目标的设定与战略选择

随着第二步战略目标的基本实现，我国的社会经济发展已经进入到全面建设小康社会的崭新的阶段，这个阶段意味着我国城乡生产力布局和人口的空间分布都会发生有史以来规模最大、最为深刻的变迁。全面建设小康社会的奋斗目标具有丰富的内涵，涉及广泛而丰富的社会经济结构，而推动城市化进程则是其重要内容之一。云南是一个欠发达的农业大省，农业劳动多，农村人口比重大，如何推进城市化，必须根据云南的实际，制定正确的城市化目标和发展战略。     

一种基于加权证据合成的多传感器目标识别方法

针对多传感器数据融合目标识别问题，基于D-S证据理论，提出了加权证据合成的时空域目标识别算法。该方法充分利用了多传感器多周期的测量数据，并根据D-S合成规则要求参与合成的各证据具有相同权重的特点，充分考虑了提供证据的信源即各个传感器的可靠性。在合成中，引入证据权的概念，解决了不同权重的多传感器数据融合问题，在一定程度上改善了目标识别系统的性能。最后通过计算实例表明算法是有效的。     

Identification of stem cells in small intestine and colon by marker gene Lgr5

The intestinal epithelium is the most rapidly self-renewing tissue in adult mammals. It is currently believed that four to six crypt stem cells reside at the +4 position immediately above the Paneth cells in the small intestine; colon stem cells remain undefined. Lgr5 (leucine-rich-repeat-containing G-protein-coupled receptor 5, also known as Gpr49) was selected from a panel of intestinal Wnt target genes for its restricted crypt expression. Here, using two knock-in alleles, we reveal exclusive expression of Lgr5 in cycling columnar cells at the crypt base. In addition, Lgr5 was expressed in rare cells in several other tissues. Using an inducible Cre knock-in allele and the Rosa26-lacZ reporter strain, lineage-tracing experiments were performed in adult mice. The Lgr5-positive crypt base columnar cell generated all epithelial lineages over a 60-day period, suggesting that it represents the stem cell of the small intestine and colon. The expression pattern of Lgr5 suggests that it marks stem cells in multiple adult tissues and cancers.     

Oxysterols direct immune cell migration via EBI2

Epstein-Barr virus-induced gene 2 (EBI2, also known as GPR183) is a G-protein-coupled receptor that is required for humoral immune responses; polymorphisms in the receptor have been associated with inflammatory autoimmune diseases. The natural ligand for EBI2 has been unknown. Here we describe the identification of 7α,25-dihydroxycholesterol (also called 7α,25-OHC or 5-cholesten-3β,7α,25-triol) as a potent and selective agonist of EBI2. Functional activation of human EBI2 by 7α,25-OHC and closely related oxysterols was verified by monitoring second messenger readouts and saturable, high-affinity radioligand binding. Furthermore, we find that 7α,25-OHC and closely related oxysterols act as chemoattractants for immune cells expressing EBI2 by directing cell migration in vitro and in vivo. A critical enzyme required for the generation of 7α,25-OHC is cholesterol 25-hydroxylase (CH25H). Similar to EBI2 receptor knockout mice, mice deficient in CH25H fail to position activated B cells within the spleen to the outer follicle and mount a reduced plasma cell response after an immune challenge. This demonstrates that CH25H generates EBI2 biological activity in vivo and indicates that the EBI2-oxysterol signalling pathway has an important role in the adaptive immune response.     

中频反应磁控溅射Al2O3薄膜的光学性质

采用中频反应磁控溅射技术在玻璃基片上制备了Al2O3薄膜,提出了一种利用透射光谱来简单有效地分析弱吸收薄膜的光学特性及与光学相关的其他物理特性的方法.对Al2O3薄膜进行透射谱测量,通过对薄膜折射率、吸收系数、膜厚度与入射光波长相互关系的分析,获得了Al2O3薄膜在400~1 100 nm区域内的折射率、吸收系数与入射光波长的关系式,以及Al2O3薄膜厚度的计算公式.     

超支化不饱和聚(酰胺-酯)的改性及热分解动力学

采用不同链长的十四酰氯和十八酰氯对超支化不饱和聚(酰胺-酯)(MHBP)的端羟基进行原位端基改性,制备出2种改性超支化聚合物,用傅立叶红外光谱(FTIR)、热重分析(TGA)、黏度法等对其结构及性能进行表征,并研究了它们的热分解行为及其热分解动力学.结果表明,其热分解反应不是一级反应,改性超支化聚合物的热稳定性与末端烷烃链的长度有关,用Ozawa法求出了热分解表观活化能.