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关键词： 经济增长   财政支出   工业化进程   检验   发达国家   经济发展   经济思想   哈佛大学  

摘要： 哈佛大学著名经济史学家格申克隆（1966）在观察英美等发达国家的工业化进程之后曾指出，经济愈是不发达的国家在其工业化的进程中政府的作用愈是重要。各国经济发展的历程无疑是对这一假说的最好佐证。从最初的“守夜者”到积极的调控者，政府在经济发展中的作用日益变得无以替代。经济思想的成长虽然几经政府与市场的博弈，但作为调节经济的重要手段——财政政策对经济增长的重要作用却已在经济思想中根深蒂固。

关键词： 股市发展   经济增长   单位根检验  

摘要： 关于金融体系和经济增长之间关系的争论由来已久。本文在分析国外关于这一争论的研究成果的基础上,对中国的股票市场发展与经济增长之间的关系做了一系列实证检验,考察了金融体系的一个组成部分———股票市场与经济增长的关系。检验结果说明,中国股市发展与经济增长之间的相关性不高,回归结果也不能说明中国股市发展会推动经济增长。

关键词： soil   anti-skid sand   urban dust   traffic   creosote   peak deconvolution   PCA   POLYCYCLIC AROMATIC-HYDROCARBONS   INCINERATOR FLY-ASH   DIRECTED CHEMICAL-ANALYSIS   MUNICIPAL SOLID-WASTE   GAS-CHROMATOGRAPHY   GENOTOXIC COMPONENTS   MASS-SPECTROMETRY   SOIL   BIOREMEDIATION   MULTIVARIATE  

摘要： The aim of this study was to compare the polycyclic aromatic hydrocarbon (PAH) contents in a number of complex samples, including soil samples from industrial sites, anti-skid sand, urban dust and ash samples from municipal solid waste incinerators. The samples were characterized by routine analysis of PAHs (gas chromatography-quadrupole mass spectrometry) and gas chromatography-time of flight mass spectrometry (GC-TOFMS). Classification of the samples by principal component analysis (PCA) according to their composition of PAHs revealed that samples associated with traffic and the municipal incinerator formed homogeneous clusters, while the PAH-contaminated soils clustered in separate groups. Using spectral data to resolve co-eluting chromatographic peaks, 962 peaks could be identified in the GC-TOFMS analysis of a pooled sample and 123-527 peaks in the individual samples. Many of the studied extracts included a unique set of chemicals, indicating that they had a much more diverse contamination profile than their PAH contents suggested. Compared to routine analysis, GC-TOFMS provided more detailed information about each sample and in this study a large number of alkylated PAHs were found to be associated with the corresponding unsubstituted PAHs. The possibility to filter peaks according to different criteria (e.g. to include only peaks that were detected in the analysis of another sample) was explored and used to identify unique as well as common compounds within samples. This procedure could prove to be valuable for obtaining relevant chemical data for use in conjunction with results from various biological test systems. (c) 2006 Elsevier Ltd. All rights reserved.

关键词： RESTRICTIVE COVENANTS   ECONOMICS   LABOR   PROTECTION  

摘要： The employment relationship is governed largely by contract, but with a heavy overlay of "rights": minimum terms and individual fights that are established by external law and are typically nonwaivable. But some terms Of employment are governed neither by ordinary contract nor by ordinary rights, nor even by ordinary waivable rights. Both of the two most controversial contractual instruments in employment law today-non-compete covenants and mandatory arbitration agreements-take the form of written contracts; both waive important employee rights (the right to compete postemployment, the right to litigate future claims); and both are subject to substantive criteria of validity that are set by external law. Both bodies of law may be usefully described as recognizing "conditionally waivable" rights. This Article aims first to show structural parallels between non-compete covenants and mandatory arbitration agreements that place them at a distinct intermediate point along the spectrum between nonwaivable rights and ordinary contract. Second, it seeks to uncover a common logic underlying the law's choice of this particular hybrid of rights and contract. The linchpin of that common logic lies in the threat that an unregulated waiver of one right (the right to compete or to litigate future claims) poses to adjacent employee rights that the law deems nonwaivable. Third, this Article deploys that underlying logic to offer a critical assessment of the law governing non-competes and arbitration agreements. Finally, this Article tentatively explores the broader potential usefulness of conditional waivability as a way of regulating some terms Of employment. The intriguing potential of conditional waivability lies in its injection of some of the virtues of contract-especially flexibility and variability in the face of widely divergent and changing circumstances-into the Pursuit of public goals and the realization of rights in the workplace.

关键词： GENE-EXPRESSION DATA   PROSTATE-CANCER   SELECTION   SPECIMENS   RACEMASE   DESIGN  

摘要： Background: Uncertainty often affects molecular biology experiments and data for different reasons. Heterogeneity of gene or protein expression within the same tumor tissue is an example of biological uncertainty which should be taken into account when molecular markers are used in decision making. Tissue Microarray ( TMA) experiments allow for large scale profiling of tissue biopsies, investigating protein patterns characterizing specific disease states. TMA studies deal with multiple sampling of the same patient, and therefore with multiple measurements of same protein target, to account for possible biological heterogeneity. The aim of this paper is to provide and validate a classification model taking into consideration the uncertainty associated with measuring replicate samples. Results: We propose an extension of the well-known Naive Bayes classifier, which accounts for biological heterogeneity in a probabilistic framework, relying on Bayesian hierarchical models. The model, which can be efficiently learned from the training dataset, exploits a closed- form of classification equation, thus providing no additional computational cost with respect to the standard Naive Bayes classifier. We validated the approach on several simulated datasets comparing its performances with the Naive Bayes classifier. Moreover, we demonstrated that explicitly dealing with heterogeneity can improve classification accuracy on a TMA prostate cancer dataset. Conclusion: The proposed Hierarchical Na ve Bayes classifier can be conveniently applied in problems where within sample heterogeneity must be taken into account, such as TMA experiments and biological contexts where several measurements ( replicates) are available for the same biological sample. The performance of the new approach is better than the standard Naive Bayes model, in particular when the within sample heterogeneity is different in the different classes.

关键词： model accuracy   sample survey   study design   classification trees   lichens   accuracy assessment   probability samples   non-probability samples   HABITAT   RARE   CONSERVATION   INFORMATION   VARIABLES   UTAH  

摘要： We evaluated the effects of probabilistic (hereafter DESIGN) and non-probabilistic (PURPOSIVE) sample surveys on resultant classification tree models for predicting the presence of four lichen species in the Pacific Northwest, USA. Models derived from both survey forms were assessed using an independent data set (EVALUATION). Measures of accuracy as gauged by resubstitution rates were similar for each lichen species irrespective of the underlying sample survey form. Cross-validation estimates of prediction accuracies were lower than resubstitution accuracies for all species and both design types, and in all cases were closer to the true prediction accuracies based on the EVALUATION data set. We argue that greater emphasis should be placed on calculating and reporting cross-validation accuracy rates rather than simple resubstitution accuracy rates. Evaluation of the DESIGN and PURPOSIVE tree models on the EVALUATION data set shows significantly lower prediction accuracy for the PURPOSIVE tree models relative to the DESIGN models, indicating that non-probabilistic sample surveys may generate models with limited predictive capability. These differences were consistent across all four lichen species, with 11 of the 12 possible species and sample survey type comparisons having significantly lower accuracy rates. Some differences in accuracy were as large as 50%. The classification tree structures also differed considerably both among and within the modelled species, depending on the sample survey form. Overlap in the predictor variables selected by the DESIGN and PURPOSIVE tree models ranged from only 20% to 38%, indicating the classification trees fit the two evaluated survey forms on different sets of predictor variables. The magnitude of these differences in predictor variables throws doubt on ecological interpretation derived from prediction models based on non-probabilistic sample surveys. (c) 2006 Elsevier B.V. All rights reserved.

关键词： outcome   psychosis   mania   Brief Psychiatric Rating Scale   first episode   MAJOR DEPRESSIVE DISORDER   EXPRESSED EMOTION   FOLLOW-UP   NEGATIVE SYMPTOMS   PRODROMAL SIGNS   FAMILY FACTORS   FLUPHENAZINE   PREDICTION   RATIONALE   REHABILITATION  

摘要： Research on predicting and preventing episodes of schizophrenia and mood disorder lacks consistent, specific definitions of episodes. We present an operational system for identifying relapse, exacerbation, and remission of schizophrenia and bipolar disorder within longitudinal studies that involve repeated symptom assessments. Three major classes of episodic outcome are defined: relapse or significant exacerbation, nonrelapse, and stable, severe persisting symptoms. These major classes are further subdivided to distinguish nine categories of episodic outcome. To examine ease of use, interrater reliability, and validity, the classification system was applied to recent-onset samples of schizophrenia patients (N=77) and bipolar mood disorder patients (N=23) followed on medication for 9- to 12-month periods. A range of episodic outcomes were distinguished with high interrater reliability. Despite being prescribed continuous medication, 21% of the recent-onset schizophrenia patients and 61% of bipolar patients met criteria for relapse or significant exacerbation during this follow-up period. Predictive relationships support the validity of this system for classifying episodes. A computer program is available to facilitate its use. Use of these explicit definitions of episodes may help to clarify the relationship between episodic outcome and other fundamental domains of illness outcome, particularly other symptom dimensions, work functioning, and social functioning. (c) 2005 Elsevier Ireland Ltd. All rights reserved.

关键词： 标本   涂片   革兰染色  

摘要： 标本直接涂片革兰染色有助于正确鉴别标本来源和性质,判断机体某些系统的微生态是否平衡,有助于对感染菌的判断,有助于提高标本阳性检出率,有助于临床早诊断,早治疗。总之,可以为临床提供科学的诊疗依据。

关键词： PARTNERSHIP (Business)   FERMENTATION   INDUSTRIAL microbiology   INVESTMENTS   RESEARCH & development   BACTERIA  

摘要： Tate & Lyle and Microbia Precision Engineering(MPE)are expected to announcethis week the formation of a five-year partnership to develop fermentation-derived ingredients forfood and industrial ***-based Tate & Lyle is one of the world's major producers offermentation-based chemicals and other ingredients.

关键词： amphotericin B   solid state NMR   REDOR   phospholipid   lipid bilayer   LIPID BILAYER-MEMBRANES   ECHO DOUBLE-RESONANCE   ANGLE-SPINNING NMR   PERMEABILIZING ACTIVITY   PHOSPHOLIPID-BILAYERS   ANTIFUNGAL AGENTS   ROTATING SOLIDS   CHAIN-LENGTH   STEROL   CHOLESTEROL  

摘要： The membrane interaction of amphotericin B (AmB), one of the most important anti-fungal drugs, was investigated by solid state NMR measurements of uniformly C-13-enriched AmB, which was prepared by the culture of the drug-producing microorganism in the presence of [u-C-13(6)]glucose. All the C-13 NMR signals of AmB upon binding to DLPC membrane were successfully assigned on the basis of the C-13-C-13 correlation spectrum. C-13-P-31 RDX (Rotational-Echo Double Resonance for X-clusters) experiments clearly revealed the REDOR dephasing effects for carbon atoms residing in the both terminal parts, whereas no dephasing was observed for the middle parts including polyolefinic C20-C33 and hydroxyl-bearing C8/C9 parts. These observations suggest that AmB binds to DLPC membrane with a high affinity to the phospholipid and spans the membrane with a single molecular length. (c) 2006 Elsevier Ltd. All rights reserved.