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关键词： 缩短平均住院日   检验科   医院质量管理   医疗费用   医疗机构   卫生资源   医疗质量   医疗安全  

摘要： 平均住院日是反映医院质量管理水平的一项重要指标。各级医疗机构都在努力缩短平均住院日，以更有效地利用现有的卫生资源，减少患者的医疗费用和政府用于民众的医疗费用的开支。在保证医疗安全和医疗质量，不改变疾病治疗的基本科学规律的前提下，缩短平均住院日，对于政府、患者和医院都颇为受益。但其中医护人员要付出巨大的辛苦。

关键词： Clustering   Mass spectrometry   Hybrid algorithm   Feature selection   Classification  

摘要： Mass spectrometry (MS)-based proteomics has been established as a standard way for biomarker discovery and early detection of disease from the proteome level. However, the data generated by MS technology are noisy, have a lot of redundancy, and most importantly have low sample-to-dimension ratio. Therefore, successful analysis of MS data heavily relies on the algorithmic and data mining techniques used to extract information. In this paper, we briefly discuss some of the commonly used algorithms applied to mass-to-charge (m/z) feature selection, and propose a k-means clustering based hybrid algorithm to address the high-dimension and high-correlation issues associated with this task. Our k-means clustering based hybrid algorithm incorporates the advantages of both filter- and wrapper-based feature selection algorithms. A special iterative procedure is introduced to overcome the instability of k-means clustering and genetic algorithm. By comparing the proposed hybrid system with several popular m/z feature selection algorithms using 10 different classifiers, we show that the proposed algorithm is able to select m/z features with lower correlation while achieving higher sample classification accuracies. The m/z feature selection results also indicate that the proposed hybrid algorithm is very stable despite its stochastic nature. (C) 2010 Elsevier B.V. All rights reserved.

关键词： Enzyme catalysis   Tunneling   Barrier compression   Promoting mode   Kinetic isotope effect   Catalytic entropy  

摘要： The idea that tunneling is enhanced by the compression of the donor-acceptor distance has attracted significant interest. In particular, recent studies argued that this proposal is consistent with pressure effects on enzymatic reactions, and that the observed pressure effects support the idea of vibrationally enhanced catalysis. However, a careful analysis of the current works reveals serious inconsistencies in the evidence presented to support these hypotheses. Apparently, tunneling decreases upon compression, and external pressure does not lead to the applicable compression of the free energy surface. Additionally, pressure experiments do not provide actual evidence for vibrationally enhanced catalysis. Finally, the temperature dependence of the entropy change in hydride transfer reactions is shown to reflect simple electrostatic effects. (C) 2010 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.

关键词： 粮油食品   食品安全   质量检验   职责  

摘要： 长期以来粮油质量检测工作，受到广大粮油工作者的普遍重视，在粮油市场化、国际化的今天，应对粮油质量检测工作进行新的认识。粮油食品是广大民众不可缺少的食品，因此粮油食品安全问题就值得大家关注，而在粮油加工企业中粮油的质量检验又做为企业的”眼睛”不仅有保障了老百姓食品安全的职责。同时也有维护企业良好信誉的职责。

关键词： Matrix effects   Ion suppression   Plasma   Urine   Sample preparation   SPE   MS  

摘要： An exhaustive classification of matrix effects occurring when a sample preparation is performed prior to liquid-chromatography coupled to mass spectrometry (LC-MS) analyses was proposed. A total of eight different situations were identified allowing the recognition of the matrix effect typology via the calculation of four recovery values. A set of 198 compounds was used to evaluate matrix effects after solid phase extraction (SPE) from plasma or urine samples prior to LC-ESI-MS analysis. Matrix effect identification was achieved for all compounds and classified through an organization chart. Only 17% of the tested compounds did not present significant matrix effects. (C) 2009 Elsevier B.V. All rights reserved.

关键词： 智能包装   应用   分类   智能材料   包装材料   信息收集   包装系统   化管理  

摘要： 什么是智能包装 随着智能材料不断发展．它的应用范围拓展到了包装．于是出现了。智能包装“的概念．所谓智能包装，是指利用新型的包装材料．结构与形式对商品的质量和流通安全性进行积极干预与保障；利用信息收集．管理，控制与处理技术完成对运输包装系统的优化管理等．

关键词： 烟蒂   痕迹   物证   现场   法医学  

摘要： 目的本文通过探讨现场烟蒂的提取、检验、分析等一系列手段,探讨烟蒂痕迹物证在犯罪现场的作用。方法运用法医物证、理化、病理学等方法检验烟蒂物证。结果以法医学检验获得的有关证据,建立、规范现场烟蒂的提取、检验、分析等一系列手段。结论烟蒂痕迹物证在犯罪现场有个人识别、犯罪现场重建和心理分析等作用,均有利于刑事犯罪案件的侦破和为法律诉讼服务。

关键词： bias (epidemiology)   diabetes mellitus   type 2   epidemiologic research design   genotype-environment interaction   meta-analysis   PPAR gamma  

摘要： Statistical interactions between genes and environmental exposures with respect to disease outcomes may help to identify biologic mechanisms and pathways and inform behavioral interventions. The number of persons required for a single study to have sufficient statistical power to detect such interactions may be considered prohibitively large, making a meta-analysis of published literature an apparently attractive alternative. However, meta-analysis of gene-environment interactions using published literature is challenging, with the conclusions being likely to suffer from bias and lack of generalizability. The authors highlight these challenges and biases using an illustrative example: meta-analysis of interactions between the Pro12Ala variant of the peroxisome proliferator-activated receptor gamma (PPAR gamma) gene and various diet and lifestyle factors in the risk of diabetes. The authors conclude that literature-based meta-analysis conducted to examine gene-environment interactions is unlikely to provide a meaningful quantitative conclusion. Alternative strategies are required, including analyses in scientific consortia established to assess main genetic effects, where individual participant data can be shared, allowing both greater power and consistency of analysis methods. However, these consortia are likely to be limited by lack of standardization of the measures of environmental factors. This issue may ultimately only be resolvable by the de novo establishment of large single or multicenter cohorts using comparable methods.

关键词： incremental learning   parametric decomposition   classification   data mining   algorithm  

摘要： In classification task training, sample size and high feature dimensionality enhance the computational complexity of algorithms. Therefore, many algorithms tend to work with reduced feature set and hence ignore contribution of all relevant parameters. This paper presents an Incremental, Simple, Efficient and Accurate (I-SEA) algorithm to consider contribution of all available relevant parameters while keeping the computational complexity and accuracy within acceptable limits. I-SEA partitions the training sample space during the preprocessing stage as part of learning. Partitioning is done based on parameter values, taking one at a time, resulting into equivalent classes with respect to the parameter. During classification, these sets are selected based on parameter values of the test case and the result is collated. The algorithm supports incremental learning at a cost of O(m). The average case complexity of classification is O(m (Iog(2) n(2)))

关键词： Ectomycorrhizal rhizomorphs   Fine roots   Minirhizotron   Soil CO2 production   Soil sensors   Structural equation model  

摘要： Soils play a critical role in the global carbon cycle, yet the biophysical factors regulating soil CO2 dynamics remain unclear. We combined high-frequency in situ observations of fine roots and ectomycorrhizal (EM) fungi with data from multiple soil sensor arrays to examine the biophysical interactions influencing soil CO2 production for one year in a mixed conifer forest. Using structural equation modeling we constructed a hypothesized model to test for causal interactions among environmental factors, biotic factors, and soil CO2 dynamics throughout the soil profile. According to our model, seasonal variation in CO2 production was significantly influenced by EM rhizomorph production, soil temperature, and soil moisture. Fine root production, on the other hand, did not appear to significantly influence soil CO2 production. The relationship between EM rhizomorph production and soil CO2 production was also supported by a zero temporal lag between these two measurements in a cross-correlation analysis. In contrast, CO2 production increased before fine root production suggesting that these two measurements were decoupled in time. Results from this study highlight the need to better understand differences in carbon allocation between plant roots and EM fungi to improve our predictions of soil carbon dynamics under global climate change.