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关键词： 欧盟委员会   危险物质   分类   修订   法规   标签   包装   成员国  

摘要： 9月18日，欧盟委员会第31次修订统一成员国关于危险物质分类、包装和标签的法律、法规和管理规定的理事会指令67／548／EEC。

关键词： 实验室,医院   质量管理   医疗安全  

摘要： 随着卫生部<医疗机构临床实验室管理办法>的实施以及医疗质量管理年活动的开展,临床实验室面临着严峻的考验.因为它涵盖了检验科管理的方方面面,特别是对实验室安全管理和质量管理方面提出了更高的要求,这也是为了搞好'以患者为中心,以提高医疗服务质量'为主题的医院管理年活动,其实质就是全面提高医院的医疗整体质量,保障人民群众生命健康与安全.

关键词： 近红外光谱   统计量   系统聚类  

摘要： 近红外校正模型中样品的变异范围,会导致模型的预测能力下降。为此,将系统聚类法与统计量(R2统计量,半偏相关统计量SPRSQ,伪F统计量PSF,伪t2统计量PST2)相结合,指导分类建模,减小建模集的变异范围。实例表明,该方法克服了系统聚类分析中无法确定聚类数目的问题,并能剔除部分异常样品,提高了校正模型的可靠性和预测能力。

关键词： 欧盟委员会   危险物质   包装   标签   法律  

摘要： 近日，为适应技术进步，欧盟委员会第31次修订了统一成员国关于危险物质分类、包装和标签的法律、法规和管理规定的理事会指令67／548／EEC。

关键词： mu XRF   Microheterogeneity   PCA   Reference materials   Elemental analysis   TRACE-ELEMENTS   CHEMICAL-ANALYSIS   HOMOGENEITY  

摘要： Micro X-ray fluorescence (mu XRF) has been used nondestructively to investigate elemental heterogeneity by constructing two-dimensional maps of elemental concentrations in reference materials. mu XRF probes sample sizes well below the 100 mg mass usually recommended for reference materials by NIST. Multivariate methods of analysis, such as principal-component analysis (PCA), show promise in identifying whether "nugget" effects exist within a material, where an element is enriched in small, isolated areas of the sample. The PCA model is built based on data taken in one location and compared with each elemental map. This methodology is shown for several reference materials including SRM 2702 and SRM 2703 to show how PCA treatment can be used to identify which elements exhibit nugget effects within the sub-mg mass range. A method of calculating the minimum recommended mass for solid samples is suggested using PCA iteratively on X-ray maps from which adjacent data points have been averaged. This is repeated until the mass sampled in a map is indistinguishable from data taken at a single location, suggesting no nugget effects can be detected. For SRM 1577c, a mass as low as 370 mu g can be used without measurable nugget effects.

关键词： surveys   galaxies: active   galaxies: luminosity function, mass function   galaxies: statistics   radio continuum: galaxies   VLBA CALIBRATOR SURVEY   POWERFUL RADIO GALAXIES   ACTIVE GALACTIC NUCLEI   SURVEY QUASAR CATALOG   ESO IMAGING SURVEY   BL-LAC OBJECTS   LUMINOSITY FUNCTION   OPTICAL IDENTIFICATIONS   COSMOLOGICAL EVOLUTION   SKY SURVEY  

摘要： The CoNFIG (Combined NVSS-FIRST Galaxies) sample is a new sample of 274 bright radio sources at 1.4 GHz. It was defined by selecting all sources with S-1.4 GHz >= 1.3 Jy from the NRAO Very Large Array (VLA) Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty centimetres (FIRST) survey. New radio observations obtained with the VLA for 31 of the sources are presented. The sample has complete Fanaroff-Riley (FRI)/FRII morphology identification; optical identifications and redshifts are available for 80 and 89 per cent of the sample, respectively, yielding a mean redshift of similar to 0.71. One of the goals of this survey is to get better definitions of luminosity distributions and source counts of FRI/FRII sources separately, in order to determine the evolution of the luminosity function for each type of source. We present a preliminary analysis, showing that these data are an important step towards examining various evolutionary schemes for these objects and to confirm or correct the dual population unified scheme for radio active galactic nuclei (AGN). Improving our understanding of radio galaxy evolution will give better insight into the role of AGN feedback in galaxy formation.

关键词： bias (epidemiology)   genetics   genotype   likelihood functions   polymorphism   single nucleotide   CONTROL GENETIC ASSOCIATION   HARDY-WEINBERG EQUILIBRIUM   EXPOSURE MEASUREMENT ERROR   TRANSMISSION/DISEQUILIBRIUM TEST   FREQUENCY ESTIMATION   HAPLOTYPE   POWER   TESTS   PARENTS   DESIGN  

摘要： Previously, estimation of genotype misclassification of single nucleotide polymorphisms (SNPs) as encountered in epidemiologic practice and involving thousands of subjects was lacking. The authors collected representative data on approximately 14,000 subjects from 8 studies and 646,558 genotypes assessed in 2005 by means of matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Overall discordance among 57,805 double genotypes from routine quality control was 0.36%. Fitting different misclassification models by maximum likelihood assuming identical misclassification for all SNPs, the estimated misclassification probabilities ranged from 0.0000 to 0.0035. When applying the misclassification simulation and extrapolation (MC-SIMEX) method for the first time to genetic data to account for the misclassification in a reanalysis of adiponectin-encoding (APM1) gene SNP associations with plasma adiponectin in 1,770 subjects, the authors found no impact of this small error on association estimates but increased estimates for a more substantial error. This study is the first to provide large-scale epidemiologic data on SNP genotype misclassification. The estimated misclassification in this example was small and negligible for association estimates, which is reassuring and essential for detecting SNP associations. In situations with more substantial error, the presented approach using duplicate genotyping and the MC-SIMEX method is practical and helpful for quantifying the genotyping error and its impact.

关键词： computer security   pattern recognition   packed executables   computer virus detection  

摘要： Executable packing is the most common technique used by computer Virus writers to obfuscate malicious code and evade detection by anti-virus software. Universal unpackers have been proposed that can detect and extract encrypted code from packed executables, therefore potentially revealing hidden Viruses that can then be detected by traditional signature-based anti-virus software. However, universal unpackers are computationally expensive and scanning large collections of executables looking for virus infections may take several hours or even days. In this paper we apply pattern recognition techniques for fast detection of packed executables. The objective is to efficiently and accurately distinguish between packed and non-packed executables, so that only executables detected as packed will be sent to an universal unpacker, thus saving a significant amount of processing time. We show that our system achieves very high detection accuracy of packed executables with a low average processing time. (c) 2008 Elsevier B.V. All rights reserved.

关键词： 合同   法律   企业  

摘要： 企业开展营销活动离不开合同.为使合同受到法律的保护,企业要对合同的知识深刻认识,对合同的发展有所了解.文章以理论知识与实践结合的形式受法律保护为主题,重点论述了法律保护与合同形式的关系,透析了口头形式与法律保护的利弊,解析了书面形式与法律保护的实例.

关键词： supervised classification   performance estimation   confidence interval   DNA MICROARRAY DATA   ERROR RATE   BREAST-CANCER   PREDICTION   SIZE  

摘要： The interest in statistical classification for critical applications such as diagnoses of patient samples based on supervised learning is rapidly growing. To gain acceptance in applications where the subsequent decisions have serious consequences, e.g. choice of cancer therapy, any such decision support system must come with a reliable performance estimate. Tailored for small sample problems, cross-validation (CV) and bootstrapping (BTS) have been the most commonly used methods to determine such estimates in virtually all branches of science for the last 20 years. Here, we address the often overlooked fact that the uncertainty in a point estimate obtained with CV and BTS is unknown and quite large for small sample classification problems encountered in biomedical applications and elsewhere. To avoid this fundamental problem of employing CV and BTS, until improved alternatives have been established, we suggest that the final classification performance always should be reported in the form of a Bayesian confidence interval obtained from a simple holdout test or using some other method that yields conservative measures of the uncertainty. (c) 2008 Elsevier B.V. All rights reserved.