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关键词： 航天产品   质量控制过程   质量检验   过程质量控制   质量问题   复杂产品   软件组成   接口关系  

摘要： 航天产品由众多分系统、子系统、零部件、元器件和软件组成的复杂产品，具有技术先进、结构和接口关系复杂等特点。因此，其生产过程质量控制十分复杂，稍有疏忽可能造成产品全系统的质量问题，有些质量问题是不可逆的。中外航天史上，

关键词： cancer   Internet   support   appraisal   trauma   self-appraisal  

摘要： The advent of online communication is transforming how older adults find social support with a community of peers who cope with similar health issues. This article explores whether participation in virtual health support groups demonstrates a significant interaction with users' appraisal of their illness experience and predicts self-reappraisal among adults 50 years of age and older (N = 157). Hierarchical multiple regressions demonstrate the significance of the combined effect of virtual health support and its interaction with illness appraisal measures to predict the outcome variable of self-reappraisal. The results indicate that even though appraisal of cancer as a traumatic experience reduces positive self-reappraisal, those who appraised their illness to have been a traumatic experience perceived virtual support to be more influential on their sense of positive change after cancer. In contrast, perceived benefit of virtual support on positive self-appraisal is reduced if illness is appraised as an opportunity for personal growth.

关键词： Bioinformatics   Biomarkers   Fish classification   Naive Bayes classifier  

摘要： There is an increasing demand to develop cost-effective and accurate approaches to analyzing biological tissue samples. This is especially relevant in the fishing industry where closely related fish samples can be mislabeled, and the high market value of certain fish leads to the use of alternative species as substitutes, for example, Barramundi and Nile Perch (belonging to the same genus, Lates). There is a need to combine selective proteomic datasets with sophisticated computational analysis to devise a robust classification approach. This paper describes an integrated MS-based proteomics and bioinformatics approach to classifying a range of fish samples. A classifier is developed using training data that successfully discriminates between Barramundi and Nile Perch samples using a selected protein subset of the proteome. Additionally, the classifier is shown to successfully discriminate between test samples not used to develop the classifier, including samples that have been cooked, and to classify other fish species as neither Barramundi nor Nile Perch. This approach has applications to truth in labeling for fishmongers and restaurants, monitoring fish catches, and for scientific research into distances between species.

关键词： Antarctic   Yeast   Cold-active enzymes   Biodiversity   Biotechnology  

摘要： The aim of the present study was to investigate the taxonomic identity of yeasts isolated from the Antarctic continent and to evaluate their ability to produce enzymes (lipase, protease and xylanase) at low and moderate temperatures. A total of 97 yeast strains were recovered from marine and terrestrial samples collected in the Antarctica. The highest amount of yeast strains was obtained from marine sediments, followed by lichens, ornithogenic soils, sea stars, Salpa sp., algae, sea urchin, sea squirt, stone with lichens, Nacella concinna, sea sponge, sea isopod and sea snail. Data from polyphasic taxonomy revealed the presence of 21 yeast species, distributed in the phylum Ascomycota (n = 8) and Basidiomycota (n = 13). Representatives of encapsulated yeasts, belonging to genera Rhodotorula and Cryptococcus were recovered from 7 different Antarctic samples. Moreover, Candida glaebosa, Cryptococcus victoriae, Meyerozyma (Pichia) guilliermondii, Rhodotorula mucilaginosa and R. laryngis were the most abundant yeast species recovered. This is the first report of the occurrence of some species of yeasts recovered from Antarctic marine invertebrates. Additionally, results from enzymes production at low/moderate temperatures revealed that the Antarctic environment contains metabolically diverse cultivable yeasts, which could be considered as a target for biotechnological applications. Among the evaluated yeasts in the present study 46.39, 37.11 and 14.43 % were able to produce lipase (at 15 A degrees C), xylanase (at 15 A degrees C) and protease (at 25 A degrees C), respectively. The majority of lipolytic, proteolytic and xylanolytic strains were distributed in the phylum Basidiomycota and were mainly recovered from sea stars, lichens, sea urchin and marine sediments.

关键词： Raman spectroscopy   Rice   Multivariate data analysis   Geographical origin   Adulteration  

摘要： Rice has played an important role in staple food supply of over approximately one-half of the world population. In this study, Raman spectroscopy and several multivariate data analysis methods were applied for discrimination of rice samples from different districts of China. A total of 42 samples were examined. It is shown that the representative Raman spectra in each group are different according to geographical origin after baseline correction to enhance spectral features. Moreover, adulteration of rice is a serious problem for consumers. In addition to the obvious effect on producer profits, adulteration can also cause severe health and safety problems. Paraffin was added to give the rice a desirable translucent appearance and increase its marketability. Detection of paraffin in the adulterated rice samples was preliminarily investigated as well. The results showed that Raman spectroscopy data with chemometric techniques can be applied to rapid detecting rice adulteration with paraffin. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Next Generation Sequencing   Linear Discriminant Analysis   Next Generation Sequencing Technology   True Error   Next Generation Sequencing Data  

摘要： Background: A key goal of systems biology and translational genomics is to utilize high-throughput measurements of cellular states to develop expression-based classifiers for discriminating among different phenotypes. Recent developments of Next Generation Sequencing (NGS) technologies can facilitate classifier design by providing expression measurements for tens of thousands of genes simultaneously via the abundance of their mRNA transcripts. Because NGS technologies result in a nonlinear transformation of the actual expression distributions, their application can result in data that are less discriminative than would be the actual expression levels themselves, were they directly observable. Results: Using state-of-the-art distributional modeling for the NGS processing pipeline, this paper studies how that pipeline, via the resulting nonlinear transformation, affects classification and feature selection. The effects of different factors are considered and NGS-based classification is compared to SAGE-based classification and classification directly on the raw expression data, which is represented by a very high-dimensional model previously developed for gene expression. As expected, the nonlinear transformation resulting from NGS processing diminishes classification accuracy;however, owing to a larger number of reads, NGS-based classification outperforms SAGE-based classification. Conclusions: Having high numbers of reads can mitigate the degradation in classification performance resulting from the effects of NGS technologies. Hence, when performing a RNA-Seq analysis, using the highest possible coverage of the genome is recommended for the purposes of classification.

关键词： CLASSIFICATION   POLYGONS   ACCURACY   DATA analysis   SYSTEMS design   SAMPLING (Statistics)  

摘要： Reference polygons are homogenous areas that aim to provide the best available assessment of ground condition that the user can identify. Delineation of such polygons provides a convenient and efficient approach for researchers to identify training and validation data for supervised classification. However, the spatial dependence of training and validation data should be taken into account when the two data sets are obtained from a common set of reference polygons. We investigate the effect on classification accuracy and the accuracy estimates derived from the validation data when training and validation data are obtained from four selection schemes. The four schemes are composed of two sampling designs (simple random and systematic) and two methods for splitting sample points between training and validation (validation points in separate polygons from training points and validation points and training points split within the same polygons). A supervised object-based classification of the study region was repeated 30 times for each selection scheme. The selection scheme did not impact classification accuracy, but estimates of overall (OA), user's (UA), and producer's (PA) accuracies produced from the validation data overestimated accuracy for the study region by about 10%. The degree of overestimation was slightly greater when the validation sample points were allowed to be in the same polygons as the training data points. These results suggest that accuracy estimates derived from splitting training and validation within a limited set of reference polygons should be regarded with suspicion. To be fully confident in the validity of the accuracy estimates, additional validation sample points selected from the region outside the reference polygons may be needed to augment the validation sample selected from the reference polygons.

关键词： 合意就业获取   人力资本   社会资本  

摘要： 基于中国微观调查数据估计发现,人力资本、社会资本对劳动者获取合意就业存在显著的正向作用。社会资本在劳动者获取合意就业中的作用,相当于劳动者增加5—10年的教育所产生的影响。平均处理效应方法的估计结果表明,无论劳动者在寻求就业时是否运用社会资本,人力资本对合意就业获取的影响并无差异;社会资本对合意就业的作用,未因个体未观察到的特征而改变。进一步分析发现,西部地区劳动力市场上社会资本的作用,显著大于东部和中部地区。

关键词： 出口   计价货币   决定因素  

摘要： 本文系统梳理了"新开放经济宏观经济"(NOEM)框架下的出口计价货币选择理论,分别从局部均衡模型到一般均衡模型,从静态模型到动态模型分析了出口计价货币选择的决定机制和主要决定因素。分析显示,除历史因素外,一国货币是否能成为国际贸易计价货币,主要由该国经济规模、出口市场份额、出口产品差异度、出口产业结构类型及该国币值的稳定性等因素共同决定。

关键词： 木材检验技术   木材运输   作用  

摘要： 介绍了木材检验技术在木材运输检验中的作用,以期为林业管理人员提供有价值的借鉴和参考,促进林业经济良性的发展。