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关键词： Contracts   Contract theory   Economic theory   Consumer information   Contract enforcement   Consumer choice   Product standards   Economic costs   Police services  

关键词： ROTAVIRUSES   VIRAL genomes   DOUBLE-stranded RNA   VIRAL proteins   INFLUENZA A virus   BACTERIOPHAGES   RNA viruses   MOLECULAR virology  

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： ELECTRIC properties of metallic films   OXIDATION-reduction reaction   SWITCHING theory   TRANSITION metal oxides   TITANIUM dioxide films   NICKEL compounds   ELECTRIC conductivity   OHMIC contacts  

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： Contracts   Consumer equilibrium   Consumer economics   Consumer prices   Economic competition   Reading   Consumer spending   Capital costs   Names  

摘要： It is well-known that a monopolist cannot commit to offer a high-quality contract to a consumer reading costs are positive. This paper shows that this also holds in a competitive environment with consumer heterogeneity if the contract space is unrestricted. If firms can offer standardized contracts from a finite set, however, each with a standardized name, this paper shows that, when reading costs are not too large, there exists an equilibrium in which firms offer the most efficient contracts from the set of named contracts and consumers purchase the most efficient contracts offered without incurring any reading costs. (JEL: D18, D86, K12, L15)

关键词： Binary data   Confidence interval   Misclassification   Risk difference   Validation substudy  

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： Gene Selection   LDPC Code   Binary Classifier   Check Node   Multiclass Classification  

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： 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： 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。