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关键词： 实验室检验   检验结果   实时监控   室内质控   水   卫生资源   检验工作   看病难  

摘要： 进行检验结果互认是合理有效利用卫生资源,解决看病难与看病贵的一项重要措施,势在必行;检验结果互认,对检验工作而言是一个新课题,也是一个新的机遇和挑战[1,2],它对同一区域内的实验室是一个普遍提高水平的过程,

关键词： 劳动合同   案例   劳动者   用人单位   工作岗位   工资差额   工资标准   加班工资   市场部   销售部  

摘要： 您有何法律问题需要咨询,请发电子邮件至本刊编辑部bjb@***或北京长安律师事务所资深律师梁学军lawyer591@***签订劳动合同是用工单位与劳动者之间确立劳动关系,明确双方权利和义务的一种重要手段。然而许多劳动争议的出现往往也源于劳动合同。7月,就业高峰即将到来,本刊特整理一些与劳动合同有关的案例,供广大经营者参考。案例:2011年2月,赵同(化名)与扬州一家服装公司签订了为期3年的劳动合同,在公司销售部工作,月薪9000元。7月1日,因为公司市场部人员紧张,公司书面通知赵同,将其暂时调入市场部工作。后公司按市场部工资标准支付赵同7月份工资7000元。

关键词： DNA damage   Phosphorylation   Schizosaccharomyces pombe   Cell fusion   Synthesis phase   Immunoprecipitation   Saccharomyces cerevisiae   Sequence motif analysis  

摘要： In response to DNA damage, the eukaryotic genome surveillance system activates a checkpoint kinase cascade. In the fission yeast Schizosaccharomyces pombe, checkpoint protein Crb2 is essential for DNA damage-induced activation of downstream effector kinase Chk1. The mechanism by which Crb2 mediates Chk1 activation is unknown. Here, we show that Crb2 recruits Chk1 to double-strand breaks (DSBs) through a direct physical interaction. A pair of conserved SQ/TQ motifs in Crb2, which are consensus phosphorylation sites of upstream kinase Rad3, is required for Chk1 recruitment and activation. Mutating both of these motifs renders Crb2 defective in activating Chk1. Tethering Crb2 and Chk1 together can rescue the SQ/TQ mutations, suggesting that the main function of these phosphorylation sites is promoting interactions between Crb2 and Chk1. A 19-amino-acid peptide containing these SQ/TQ motifs is sufficient for Chk1 binding in vitro when one of the motifs is phosphorylated. Remarkably, the same peptide, when tethered to DSBs by fusing with either recombination protein Rad22/Rad52 or multi-functional scaffolding protein Rad4/Cut5, can rescue the checkpoint defect of crb2D. The Rad22 fusion can even bypass the need for Rad9-Rad1-Hus1 (9-1-1) complex in checkpoint activation. These results suggest that the main role of Crb2 and 9-1-1 in DNA damage checkpoint signaling is recruiting Chk1 to sites of DNA lesions.

关键词： Bartlett's decomposition   Cholesky's decomposition   FDC   Hypothesis testing   Small sample  

摘要： The variability and complex relationships among process and equipment variables in the hi-tech manufacturing processes, such as semiconductor fabrication, can be characterized by the sample covariance matrix. Test of covariance changes becomes critical for effective fault detection and classification (FDC). However, in modern made-to-order manufacturing, the product-mix is usually high while the order size is becoming smaller. The sample size in such a manufacturing situation becomes an issue diminishing the applicability of existing methods. In view of this point, this paper proposes statistical inference procedures pertaining to detecting change of covariance matrix without demanding a large sample. We apply Bartlett's decomposition and Cholesky's decomposition theories to obtain a matrix T with nice distribution property. Statistical hypothesis testing procedures for possible changes of the covariance matrix are then proposed via aggregating entries of T. The change pattern of T is also studied to construct fault classification rules. Monte Carlo simulation and a dataset collected from an actual semiconductor manufacturing tool are further used to demonstrate the usefulness of our method in FDC. (C) 2012 Elsevier Ltd. All rights reserved.

关键词： Singular Value Decomposition   Global Test   Predictive Classification   Singular Value Decomposition Method   Molecular Signature Database  

摘要： Background: Analysis of gene expression data in terms of a priori-defined gene sets has recently received significant attention as this approach typically yields more compact and interpretable results than those produced by traditional methods that rely on individual genes. The set-level strategy can also be adopted with similar benefits in predictive classification tasks accomplished with machine learning algorithms. Initial studies into the predictive performance of set-level classifiers have yielded rather controversial results. The goal of this study is to provide a more conclusive evaluation by testing various components of the set-level framework within a large collection of machine learning experiments. Results: Genuine curated gene sets constitute better features for classification than sets assembled without biological relevance. For identifying the best gene sets for classification, the Global test outperforms the gene-set methods GSEA and SAM-GS as well as two generic feature selection methods. To aggregate expressions of genes into a feature value, the singular value decomposition (SVD) method as well as the SetSig technique improve on simple arithmetic averaging. Set-level classifiers learned with 10 features constituted by the Global test slightly outperform baseline gene-level classifiers learned with all original data features although they are slightly less accurate than gene-level classifiers learned with a prior feature-selection step. Conclusion: Set-level classifiers do not boost predictive accuracy, however, they do achieve competitive accuracy if learned with the right combination of ingredients. Availability: Open-source, publicly available software was used for classifier learning and testing. The gene expression datasets and the gene set database used are also publicly available. The full tabulation of experimental results is available at http://***/CESLT.

关键词： XENOGRAFTS   NUCLEOTIDE sequence   MIXTURES   CLASSIFICATION   DATABASES   BIOINFORMATICS  

摘要： Motivation: Shotgun sequence read data derived from xenograft material contains a mixture of reads arising from the host and reads arising from the graft. Classifying the read mixture to separate the two allows for more precise analysis to be performed. Results: We present a technique, with an associated tool Xenome, which performs fast, accurate and specific classification of xenograft-derived sequence read data. We have evaluated it on RNA-Seq data from human, mouse and human-in-mouse xenograft datasets.

关键词： Uncertainty   Exposure   Fish   Blood   Mercury   Longitudinal   Methylmercury  

摘要： Background: The most prominent non-occupational source of exposure to methylmercury is the consumption of fish. In this study we examine a fish consuming population to determine the extent of temporal exposure and investigate the extent to which single time estimates of methylmercury exposure based on blood-Hg concentration can provide reliable estimates of longer-term average exposure. Methods: Blood-mercury levels were obtained from a portion of the Arsenic Mercury Intake Biometric Study (AMIBS) cohort. Specifically, 56 Japanese women residing in the Puget Sound area of Washington State, US were sampled on three occasions across a one-year period. Results: An average of 135 days separated samples, with mean blood-mercury levels for the visits being 5.1, 6.6 and 5.0 mu g/l and geometric means being 2.7, 4.5 and 3.1 mu g/l. The blood-mercury levels in this group exceed national averages with geometric means for two of the visits being between the 90th and 95th percentiles of nationally observed levels and the lowest geometric mean being between the 75th and 90th percentile. Group means were not significantly different across sampling periods suggesting that exposure of combined subjects remained relatively constant. Comparing intra-individual results over time did not reveal a strong correlation among visits (r = 0.19, 0.50, 0.63 between 1st and 2nd, 2nd and 3rd, and 1st and 3rd sample results, respectively). In comparing blood-mercury levels across two sampling interval combinations (1st and 2nd, 2nd and 3rd, and 1st and 3rd visits, respectively), 58% (n = 34), 53% (n = 31) and 29% (n = 17) of the individuals had at least a 100% difference in blood-Hg levels. Conclusions: Point estimates of blood-mercury, when compared with three sample averages, may not reflect temporal variability and individual exposures estimated on the basis of single blood samples should be treated with caution as indicators of long-term exposure. Reliance on single blood samples can make pre

关键词： 社会网络   激励强度   劳动合同  

摘要： 当前中国出现了所谓的"民工荒",这意味着劳动力供需状况即将迎来一个转折点,这一转变会带来多重后果。本文通过一个案例研究,提出如下可供实证检验的命题:随着农村剩余劳动力供给的减少,企业会改变其用工制度,原先的激励强度较低的劳动合同形式会让位于激励强度较高的劳动合同形式,这会诱使工人付出更多的努力,在一定程度上还可以缓解企业由于工资上升而带来的成本压力;此外,随着农村经济社会的发展,社会资本的作用不仅在减弱,而且自身内容和作用方式也会发生变化。

关键词： 智能包装   分类   食品科学   氧气吸收剂   包装技术   质量安全   生物技术   信息技术  

摘要： 使商品具有"交流"功能的智能包装,能够提高商品质量和加强商品安全性,对方便消费者选择物品有重要意义。本文介绍了智能包装的概念和分类,同时介绍了最新的智能包装装置,如条形码、RFID标签、气体指示器、生物传感器和时间—温度指示器等。

关键词： 足迹系统   足迹系统检验   关系   构成   作用  

摘要： 在足迹检验中,必须认识到足迹是一个"信息系统",充分理解并发挥足迹各子系统在检验中的作用,摒除单一或割裂的检验习惯,变一维式检验为多维式的系统检验,从而实现足迹检验的目的。