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121.
网络廉政舆情是把双刃剑,有利有弊,对网络廉政舆情及时搜集、科学研判、处置得当,将有利于推进高校的纪检监察工作。当前存在诸多高校负面网络廉政舆情,高校纪检监察部门在处置负面网络廉政舆情方面存在诸多误区,要有效处置负面网络廉政舆情,高校纪检监察部门应确立正确的原则,构建相应的机制。  相似文献   
122.
The semi-global stabilization problem for a class of nonlinear systems with state time-delay is addressed in this paper. By using Lyapunov-Krasovskii functional method and homogeneous domination approach, a homogeneous observer and an output feedback controller with a scaling gain are designed. Then the scaling gain is adjusted such that the closed-loop system is semi-global asymptotically stable. A numerical example is presented to illustrate the effectiveness of the obtained results in this paper.  相似文献   
123.
以武警指挥学院图书馆为例,对学员读者入馆和图书借阅情况进行了统计分析,揭示了读者的借阅需求和阅读倾向,提出了提高馆藏图书资源借阅流通率的合理化建议。  相似文献   
124.
文章分析了钢筋混凝土框架结构施工中的工艺流程、质量控制工作,对工艺中存在的质量问题提出了相应的控制措施,以供工程技术人员参考。  相似文献   
125.
126.
The effects of V-bending process, continuous bending process and combination process on the microstructure and mechanical properties and formability of an AZ31 magnesium alloy sheet were investigated. The experimental results showed that no twins were found in the microstructure of all samples after processes due to the fine grain. The V-bending and continuous bending processes were proved to be an effective approach to modify the mechanical properties and formability. While the samples after the combination process exhibited better mechanical properties and formability than the single processed sample. The yield strength significantly decreased with the value of 100 MPa and the fracture elongation enhanced to 18.3% at room temperature. The Erichsen value was 5.0 mm which was significantly increased by 117% compared with as-received sample. The superior formability of combination processed samples was mainly attributed to the smaller r-value and n-value.  相似文献   
127.
针对我国乡镇企业发展空间非均衡问题,选取2003-2012年乡镇企业总产值和乡镇企业营业收入2个指标数据,采用基尼系数法,分析了我国乡镇企业发展空间非均衡的特征、程度及其来源。结果表明:我国乡镇企业空间非均衡程度最大的是西部,其次是东部和中部地区最小。全国整体以及东、西部地区内部乡镇企业发展的空间非均衡程度均呈现进一步加深趋势,中部地区乡镇企业发展的空间均衡程度得到小幅缓解。区域间差距与剩余项差距反向变动是引致我国乡镇企业发展空间非均衡程度发生变动的重要因素。  相似文献   
128.
A second generation human haplotype map of over 3.1 million SNPs   总被引:2,自引:0,他引:2  
We describe the Phase II HapMap, which characterizes over 3.1 million human single nucleotide polymorphisms (SNPs) genotyped in 270 individuals from four geographically diverse populations and includes 25-35% of common SNP variation in the populations surveyed. The map is estimated to capture untyped common variation with an average maximum r2 of between 0.9 and 0.96 depending on population. We demonstrate that the current generation of commercial genome-wide genotyping products captures common Phase II SNPs with an average maximum r2 of up to 0.8 in African and up to 0.95 in non-African populations, and that potential gains in power in association studies can be obtained through imputation. These data also reveal novel aspects of the structure of linkage disequilibrium. We show that 10-30% of pairs of individuals within a population share at least one region of extended genetic identity arising from recent ancestry and that up to 1% of all common variants are untaggable, primarily because they lie within recombination hotspots. We show that recombination rates vary systematically around genes and between genes of different function. Finally, we demonstrate increased differentiation at non-synonymous, compared to synonymous, SNPs, resulting from systematic differences in the strength or efficacy of natural selection between populations.  相似文献   
129.
With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia.  相似文献   
130.
微束X射线荧光分析谱仪及其对松针中元素的分布分析   总被引:1,自引:0,他引:1  
介绍了一种小型的微束X射线荧光分析谱仪,它是由导管X光透镜和能量色散X射线荧光分析谱仪组成.谱仪具有较高的空间分辨率和能量分辨率.使用本谱仪对松树针叶进行了微区分析,得出各种元素沿松针长度方向和横切面径向的分布规律.结果表明使用X光透镜的微束X射线荧光分析方法可以实现植物样品的微区分析,有助于进一步了解植物的生长与元素迁移的关系.  相似文献   
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