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关键词： Automating cervical neoplasia screening   Clustering densities   Cumulative log-odds   Functional data clustering   Macro-level classification   Quantitative cytology  

摘要： We consider here the problem of classifying a macro-level object based on measurements of embedded (micro-level) observations within each object, for example, classifying a patient based on measurements on a collection of a random number of their cells. Classification problems with this hierarchical, nested structure have not received the same statistical understanding as the general classification problem. Some heuristic approaches have been developed and a few authors have proposed formal statistical models. We focus on the problem where heterogeneity exists between the macro-level objects within a class. We propose a model-based statistical methodology that models the log-odds of the macro-level object belonging to a class using a latent-class variable model to account for this heterogeneity. The latent classes are estimated by clustering the macro-level object density estimates. We apply this method to the detection of patients with cervical neoplasia based on quantitative cytology measurements on cells in a Papanicolaou smear. Quantitative cytology is much cheaper and potentially can take less time than the current standard of care. The results show that the automated quantitative cytology using the proposed method is roughly equivalent to clinical cytopathology and shows significant improvement over a statistical model that does not account for the heterogeneity of the data.

关键词： Clinical relationships   Methods  

摘要： Objective: We explored parent-doctor relationships in the care of children with leukaemia from three perspectives simultaneously: parents', doctors' and observers'. Our aim was to investigate convergence and divergence between these perspectives and thereby examine the validity of unitary theory of emotionality and authority in clinical relationships. Methods: 33 audiorecorded parent-doctor consultations and separate interviews with parents and doctors, which we analysed qualitatively and from which we selected three prototype cases. Results: Across the whole sample doctors' sense of relationship generally converged with our observations of consultation, but parents' sense of relationship diverged strongly from each. Contrary to current assumptions, parents' sense of emotional connection with doctors did not depend on doctors' emotional behaviour, and parents did not feel disempowered by doctors' authority. Moreover, authority and emotionality were not conceptually distinct for parents, who gained emotional support from doctors' exercise of authority. Conclusions: The relationships looked very different from the three perspectives. These divergences indicate weaknesses in current ideas of emotionality and authority in clinical relationships and the necessity of multisource datasets to develop these ideas in a way that characterises clinical relationships from all perspectives. Practice implications: Methodological development will be needed to address the challenges posed by multisource datasets. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

关键词： Algorithms   Animals   Artificial Intelligence   Computational Biology/methods   Data Mining   Databases, Factual   Gene Expression Profiling   Humans   Models, Statistical   Principal Component Analysis   Proteins/classification   Proteomics/methods   Support Vector Machines  

摘要： The discovery of protein variation is an important strategy in disease diagnosis within the biological sciences. The current benchmark for elucidating information from multiple biological variables is the so called "omics" disciplines of the biological sciences. Such variability is uncovered by implementation of multivariable data mining techniques which come under two primary categories, machine learning strategies and statistical based approaches. Typically proteomic studies can produce hundreds or thousands of variables, p, per observation, n, depending on the analytical platform or method employed to generate the data. Many classification methods are limited by an n << p constraint, and as such, require pre-treatment to reduce the dimensionality prior to classification. Recently machine learning techniques have gained popularity in the field for their ability to successfully classify unknown samples. One limitation of such methods is the lack of a functional model allowing meaningful interpretation of results in terms of the features used for classification. This is a problem that might be solved using a statistical model-based approach where not only is the importance of the individual protein explicit, they are combined into a readily interpretable classification rule without relying on a black box approach. Here we incorporate statistical dimension reduction techniques Partial Least Squares (PLS) and Principal Components Analysis (PCA) followed by both statistical and machine learning classification methods, and compared them to a popular machine learning technique, Support Vector Machines (SVM). Both PLS and SVM demonstrate strong utility for proteomic classification problems.

关键词： 权重股   稳定性   Granger因果检验   GARCH模型  

摘要： 由于权重股在指数计算中占有较大比例,其股价行为对市场稳定性起着重要的作用。上证50指数和深证成份指数样本股集中了我国沪深两市最具代表性的90只权重股,是我国权重股的集中表现。运用Granger因果检验、将收益离差平方作为解释变量引入GARCH模型中,研究两指数分别对市场收益及波动性的影响。实证表明两指数分别与市场收益存在显著的引导关系,并且对市场波动性的影响显著为正。结论指出我国权重股并没有发挥对市场稳定性的作用,相反在一定程度上加剧了市场的波动性。

关键词： 合同制   用工   改革   劳务派遣   外包  

摘要： 医院合同制工人是直接与医院签订劳动合同,建立劳动关系的工人,主要从事辅助性、临时性、替代性工作,保障临床一线的需求。随着医院合同制工人数量逐渐增加,医院承担的管理成本和用工风险也相应提高。因此,医院积极探索,通过外包、劳务派遣等方式,对合同制工人用工形式进行改革,做到既保障临床需求、提高合同制工人的积极性,又能实现合法、高效、低风险用工。

关键词： 技术交易市场   作用路径   通径分析  

摘要： 结合理论分析和实证分析的方法,主要研究了区域创新系统中技术交易市场的作用路径问题。首先,本文分析了区域创新系统中技术交易市场的作用机理,构建了区域创新系统中技术交易市场的作用路径的理论模型。其次,以理论分析为基础,本文采用通径分析方法对技术交易市场作用于区域创新系统路径进行实证检验,目的是研究技术市场在区域创新系统中的角色存在性和角色关系地位,验证前文理论分析得到的结论:区域创新系统中技术交易市场连接研发主体和技术创新主体,即连接大学、科研院所(主要的技术供给方)和企业(主要的技术需求者)两方主体,得到的结论是区域创新系统中技术交易市场是通过作用于发明专利的规模,从而影响技术市场交易额,进而影响新产品产值,最后作用于GDP。这一结论的现实意义在于,揭示了作用对象之间的相互作用方向和作用路径,为实施技术市场发展战略提供理论依据。

关键词： Synchrotron radiation circular dichroism   spectroscopy   Protein secondary structure   Conformational changes   Macromolecular interactions  

摘要： Circular dichroism (CD) spectroscopy is a well-established technique in structural biology. The use of synchrotron radiation as an intense light source for these measurements extends the applications possible using lab-based instruments. In recent years, there has been a major growth in synchrotron radiation circular dichroism (SRCD) beamlines worldwide, including ones at the NSLS, ISA, SRS, HiSOR, BSRF, NSRRC, SOLEIL Diamond, TERAS, BESSYII, and ANKA synchrotrons. Through the coordinated efforts of beamline scientists and users at these sites, important proof-of-principle studies have been done enabling the method to be developed for novel and productive studies on biological systems. This paper describes the characteristics of SRCD beamlines and some of the new types of applications that have been undertaken using these beamlines. (C) 2010 Elsevier B.V. All rights reserved.

关键词： 独立批发商   工业品流通   渠道作用   实证检验  

摘要： 文章基于工业品流通的经验数据对批发商的渠道作用分别进行了整体判定和分类研究,实证检验显示批发商对于提高工业品流通效率具备显著的正向影响,并且批发商渠道作用的主要区间应锁定为生产资料类工业品和日用消费类工业品,未来还应进一步确定批发商渠道作用的影响因素。

关键词： 临床微生物检验   控制医院感染   监测   临床微生物室   感染性疾病   临床试验   生物制剂   住院患者  

摘要： 随着各种新发感染性疾病的涌现及新型抗生物制剂的临床试验，临床微生物室所肩负的职责和使命日益突出。微生物室提供的数据对这些疾病和新生药物的诊疗起了关键性的作用，加强住院患者的临床微生物检验与监测，对于预防和控制医院感染起着十分重要的作用。

关键词： 装备采购供应   第三方   违约处理机制  

摘要： 随着装备采购制度改革的不断深入,建立于计划经济体制下的装备采购供应活动违约处理制度已与我军装备建设发展不相适应。改革并完善我军装备采购供应违约处理制度,可借鉴美军装备采购违约处理制度建设的做法和经验,建立起第三方介入的违约处理机制,通过协商、调解、仲裁、诉讼等方式解决争端。同时,加强违约处理机构建设,在大军区以上地区设立若干仲裁委员会,并明确管辖法院,设立装备采购供应裁决法庭,规范军方的费用补偿责任。