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关键词： FORCE MICROSCOPY   INTERFACE  

摘要： The bipolar resistive switching mechanisms of a p-type NiO film and n-type TiO2 film were examined using local probe-based measurements. Scanning probe-based current-voltage (I-V) sweeps and surface potential/current maps obtained after the application of dc bias suggested that resistive switching is caused mainly by the surface redox reactions involving oxygen ions at the tip/oxide interface. This explanation can be applied generally to both p-type and n-type conducting resistive switching films. The contribution of oxygen migration to resistive switching was also observed indirectly, but only in the cases where the tip was in (quasi-) Ohmic contact with the oxide.

关键词： DOUBLE-STRANDED-RNA   NONSTRUCTURAL PROTEIN NSP2   INFLUENZA-A VIRUS   MESSENGER-RNA   BACTERIOPHAGE PHI-6   INFECTED-CELLS   CRYOELECTRON MICROSCOPY   3-DIMENSIONAL STRUCTURE   REPLICASE PARTICLE   REVERSE GENETICS  

摘要： The rotavirus (RV) genome comprises 11 segments of double-stranded RNA (dsRNA) and is contained within a non-enveloped, icosahedral particle. During assembly, a highly coordinated selective packaging mechanism ensures that progeny RV virions contain one of each genome segment. Cis-acting signals thought to mediate assortment and packaging are associated with putative panhandle structures formed by base-pairing of the ends of RV plus-strand RNAs (+RNAs). Viral polymerases within assembling core particles convert the 11 distinct +RNAs to dsRNA genome segments. It remains unclear whether RV +RNAs are assorted before or during encapsidation, and the functions of viral proteins during these processes are not resolved. However, as reviewed here, recent insights gained from the study of RV and two other segmented RNA viruses, influenza A virus and bacteriophage Phi 6, reveal potential mechanisms of RV assortment and packaging.

关键词： Binary data   Confidence interval   Misclassification   Risk difference   Validation substudy   DOUBLE SAMPLING SCHEME   ODDS RATIOS   MISCLASSIFICATION   PROPORTIONS   EXPOSURE   ERRORS  

摘要： We develop likelihood-based confidence intervals for risk difference in two-sample misclassified binary data. Such data consist of two studies. The first study is the main study where individuals are classified by an inexpensive fallible classifier which may misclassify. The second study is a validation substudy where individuals are classified by using both the fallible classifier and an expensive gold standard which classifies perfectly. We propose and examine three likelihood-based confidence interval methods and conclude that the modified Wald method applied to small-number adjusted new data performs well and has nominal coverage probabilities. (C) 2010 Elsevier B.V. All rights reserved.

关键词： 区域经济   土地市场   三部门经济增长模型   内生增长模型  

摘要： 文章利用理论分析和实证检验相结合的方法,采用2008年全国31个省和直辖市的数据来建模验证,探讨了土地市场发展和土地出让金对区域城市化和城市经济增长的作用机理。研究结果表明:一是土地市场发展与区域经济增长互为因果关系。二是土地出让金(土地成交价款)对经济增长存在显著的影响。三是土地市场发展结合着土地财政对经济增长影响的机理是土地出让金增加了地方政府的收入和支出、并增加了固定资产投资。

关键词： FEATURE-SELECTION   CANCER   PREDICTION   RULES   BIAS  

摘要： Background: Multiclass classification of microarray data samples with a reduced number of genes is a rich and challenging problem in Bioinformatics research. The problem gets harder as the number of classes is increased. In addition, the performance of most classifiers is tightly linked to the effectiveness of mandatory gene selection methods. Critical to gene selection is the availability of estimates about the maximum number of genes that can be handled by any classification algorithm. Lack of such estimates may lead to either computationally demanding explorations of a search space with thousands of dimensions or classification models based on gene sets of unrestricted size. In the former case, unbiased but possibly overfitted classification models may arise. In the latter case, biased classification models unable to support statistically significant findings may be obtained. Results: A novel bound on the maximum number of genes that can be handled by binary classifiers in binary mediated multiclass classification algorithms of microarray data samples is presented. The bound suggests that high-dimensional binary output domains might favor the existence of accurate and sparse binary mediated multiclass classifiers for microarray data samples. Conclusions: A comprehensive experimental work shows that the bound is indeed useful to induce accurate and sparse multiclass classifiers for microarray data samples.

关键词： 计价货币   微观基础   局部均衡   人民币国际化  

摘要： 在既有的基于微观视角的包含两币的局部均衡模型中引入交易货币,发现国际贸易中计价货币选择的决定因素依次为:卖方市场结构、出口品差异化程度、出口国所占目标市场份额、其他出口商的计价策略和汇率的稳定性。在同质性商品的国际贸易中,计价货币的非同质性会导致货币垄断计价。其中,进口方货币的垄断计价地位较为稳定,出口方货币垄断计价情况很少出现,交易货币的垄断计价地位需要自身汇率的稳定和出口国较大的市场份额来维持。

关键词： 党委书记   集团公司   党组织   政治   科学发展   认证   检验   中国  

摘要： 2007年，中检集团重组后，朱俊敏担任集团党委书记，充分发挥党委的政治核心作用，解放思想、实事求是，不断推动集团公司改革发展，为落实集团公司战略目标，提供政治和组织保障。

关键词： 医院感染   微生物检验   感染监测   细菌耐药   药敏试验  

摘要： 伴随着现代医学的迅速发展,各种学科新技术的渗透,新材料、新方法、侵袭性技术应用于临床,给临床诊治患者带来便利的同时,不可避免地造成医院感染。如何趋利避害、控制医院感染,已成为当前医学发展中的重要环节。

关键词： 教育   人力资本   经济增长  

摘要： 关于人力资本影响经济增长的方式有两种理论,一种认为经济增长源于人力资本的积累速度,另一种认为经济增长应该归功于人力资本存量。对年度数据进行计量分析却表明,这两种理论对于我国来说都不适应。现阶段,人力资本对我国经济增长的作用并不明显,甚至有反作用。这可以从我国经济增长方式与人力资本的发展状况中寻找原因。