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关键词： Equal environments   Twin misclassification   Heritability   ACE model   VARIANCE-COMPONENTS MODELS   ZYGOSITY   BIRTH   ERA  

摘要： Classically derived estimates of heritability from twin models have been plagued by the possibility of genetic-environmental covariance. Survey questions that attempt to measure directly the extent to which more genetically similar kin (such as monozygotic twins) also share more similar environmental conditions represent poor attempts to gauge a complex underlying phenomenon of GE-covariance. The present study exploits a natural experiment to address this issue: Self-misperception of twin zygosity in the National Longitudinal Survey of Adolescent Health (Add Health). Such twins were reared under one "environmental regime of similarity" while genetically belonging to another group, reversing the typical GE-covariance and allowing bounded estimates of heritability for a range of outcomes. In addition, we examine twins who were initially misclassified by survey assignment-a stricter standard-in three datasets: Add Health, the Minnesota Twin Family Study and the Child and Adolescent Twin Study in Sweden. Results are similar across approaches and datasets and largely support the validity of the equal environments assumption.

关键词： Vulcaniibacterium gen. nov.   Vulcaniibacterium tengchongense sp nov.   Vulcaniibacterium thermophilum comb. nov.   Rehai National Park   FATTY-ACID   BACTERIA   STENOTROPHOMONAS   CLASSIFICATION   MENAQUINONES  

摘要： A thermotolerant Gram-staining negative and aerobic bacterium, designated strain YIM 77520(T), was isolated from a geothermally heated soil sample collected at Rehai National Park, Tengchong, Yunnan Province, South-West China. Cells of the strain were found to be rod-shaped and colonies were light beige and circular. The strain was found to grow in the presence of 0-2 % (w/v) total salts (optimum, 0 %), at pH 6.0-8.0 (optimum, pH 7.0) and 25-55 A degrees C (optimum, 45 A degrees C). The only quinone detected was Q-8 and the genomic DNA G+C content was determined to be 66.9 mol%. The major fatty acids (> 10 %) were identified as iso-C-16:0 and iso-C-15:0. The phospholipids were found to consist of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, five unknown phospholipids and three aminophospholipids. Based on the 16S rRNA gene sequence analysis, strain YIM 77520(T) was found to form a cluster with Lysobacter thermophilus YIM 77875(T) and showed the highest 16S rRNA gene sequence similarity to L. thermophilus YIM 77875(T) (96.0 %). These two strains formed a distinct lineage of the family 'Xanthomonadaceae'. On the basis of the morphological and chemotaxonomic characteristics, as well as genotypic data, a new genus, Vulcaniibacterium gen. nov. is proposed with Vulcaniibacterium tengchongense sp. nov. as the type species. The type strain of V. tengchongense sp. nov. is strain YIM 77520(T) (=DSM 25623(T) = CCTCC AB 2011152(T)). Furthermore we propose that L. thermophilus Wei et al. 2012 is reclassified in the new genus as Vulcaniibacterium thermophilum comb. nov. (type strain YIM 77875(T) = CCTCC AB 2012064(T) = KCTC 32020(T)) based on polyphasic data.

关键词： Gasoline   ATR-FTIR spectroscopy   Quadratic discriminant analysis   Genetic algorithm   Successive projection algorithm   NEAR-INFRARED SPECTROSCOPY   MULTIVARIATE CALIBRATION   PERFORMANCE  

摘要： A chemometric approach has been developed for characterization of gasoline samples regarding their quality. Attenuated total reflectance - infrared spectrometric data were processed by genetic algorithm (GA) and successive projection algorithm (SPA) feature selection techniques, being employed as an initial step prior to apply a discriminative tool. It was aimed to classify the fuel samples according to their quality passed/failed data. Chemometric predictive procedures were developed using quadratic discriminant analysis (QDA) combined with GA and SPA as a feature subset and feature selection strategy. Results showed 93.3% and 95.6% accuracy for SPA-QDA and GA-QDA models respectively. (C) 2013 Elsevier Ltd. All rights reserved.

关键词： Multi-layer aquifer   Longscreen boreholes   Machine learning   Random Forest   Hydrogeochemistry   Hydrogeology   STATISTICAL-ANALYSIS   VALIDATION   EVOLUTION   MODEL  

摘要： Accurate identification of the origin of groundwater samples is not always possible in complex multilayered aquifers. This poses a major difficulty for a reliable interpretation of geochemical results. The problem is especially severe when the information on the tubewells design is hard to obtain. This paper shows a supervised classification method based on the Random Forest (RF) machine learning technique to identify the layer from where groundwater samples were extracted. The classification rules were based on the major ion composition of the samples. We applied this method to the Campo de Cartagena multi-layer aquifer system, in southeastern Spain. A large amount of hydrogeochemical data was available, but only a limited fraction of the sampled tubewells included a reliable determination of the borehole design and, consequently, of the aquifer layer being exploited. Added difficulty was the very similar compositions of water samples extracted from different aquifer layers. Moreover, not all groundwater samples included the same geochemical variables. Despite of the difficulty of such a background, the Random Forest classification reached accuracies over 90%. These results were much better than the Linear Discriminant Analysis (LDA) and Decision Trees (CART) supervised classification methods. From a total of 1549 samples, 805 proceeded from one unique identified aquifer, 409 proceeded from a possible blend of waters from several aquifers and 335 were of unknown origin. Only 468 of the 805 unique-aquifer samples included all the chemical variables needed to calibrate and validate the models. Finally, 107 of the groundwater samples of unknown origin could be classified. Most unclassified samples did not feature a complete dataset. The uncertainty on the identification of training samples was taken in account to enhance the model. Most of the samples that could not be identified had an incomplete dataset. (C) 2013 Elsevier B.V. All rights reserved.

关键词： ALKYLBENZENES  

摘要： The article discusses the Labix joint venture between chemical firms Thai Oil subsidiary Thai Paraxylene (TPX) and Mitsui & Co. for a linear alkylbenzene (LAB) production refinery in Sriracha, Thailand, noting that Hyundai was awarded the project engineering, procurement, and construction contract.

关键词： 质量安全管理   检验科   安全管理体系   检验技术   临床医学   医学检验   医疗服务   临床检验  

摘要： 随着检验技术的迅速发展,医学检验已成为临床医学的重要组成部分,在疾病的诊治中起着举足轻重的作用。为更好的发挥临床检验在医疗服务中的作用,检验质量安全管理体系的构建和完善显得尤为重要[1-2]。本科自成立质量安全管理团队以来,工作中取得了较好的效果,现将质量安全管理团队在检验科日常工作中的作用及其体会报道如下。

关键词： 传感器   监理   应用  

摘要： 本文结合作者的设备工程监理检验实践,概括阐述了传感器在监理检验行业的应用及作用。

关键词： 金相分析   刀剪   应用   显微组织   失效分析  

摘要： 本文简要介绍了金相分析对刀剪产品检验的作用，然后对这种检验方法分别在刀具、剪刀产品检验以及刀具失效分析中的应用做了具体的案例分析。

关键词： 检察技术工作   执法办案   同步录音录像   文件检验   电子数据   司法会计   服务   侦查人员  

摘要： 检察技术工作是检察工作的重要组成部分,当前,随着信息技术在社会生活中的广泛应用,修改后刑诉法、民诉法的实施以及其他相关法律、法规的进一步完善,检察技术的重要作用越来越显现。如何进一步发挥检察技术的作用,更好地为办案服务,是我们技术工作永恒的主题。一、文检技术在办理案件中所发挥的作用一是运用文检技术手段帮助侦查人员确定犯罪事实或犯罪嫌疑人,为侦查提供方向。