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关键词： Milk analysis   Solubilization with N,N-dimethylformamide, High efficiency sample introduction system   Inductively coupled plasma mass spectrometry   Principal component analysis   TRACE-ELEMENTS   ATOMIC EMISSION   COW MILK   ZINC   DIMETHYLFORMAMIDE   EXTRACTION   CALCIUM   METALS   COPPER   COAL  

摘要： A single-step procedure for trace elements analysis of milk samples is presented. Solubilization with small amounts of dymethylformamide (DMF) was assayed prior to inductively coupled plasma mass spectrometry (ICPMS) detection with a high efficiency sample introduction system. All main instrumental conditions were optimized in order to readily introduce the samples without matrix elimination. In order to assess and mitigate matrix effects in the determination of As, Cd, Co, Cu, Eu, Ga, Gd, Ge, Mn, Mo, Nb, Nd, Ni, Pb, Pr, Rb, Sm, S, Sr, Ta, Tb, V, Zn, and Zr, matrix matching calibration with Rh-103 as internal standard (IS) was performed. The obtained limits of detection were between 0.68 (Tb) and 30 (Zn) mu g L-1. For accuracy verification, certified Skim milk powder reference material (BCR 063R) was employed. The developed method was applied to trace elements analysis of commercially available milks. Principal components analysis was used to correlate the content of trace metals with the kind of milk, obtaining a classification according to adults, baby or baby fortified milks. The outcomes highlight a simple and fast approach that could be trustworthy for routine analysis, quality control and traceability of milks. (C) 2015 Elsevier B.V. All lights reserved.

关键词： 循环贸易   商业目的   民间借贷   交易形式   合同效力  

摘要： 最高人民法院在最近做出的关于循环贸易的终审判决中,一改以往合同无效的裁判路径,认定合同有效。这一转变的原因有具体个案的差异,更体现了最高院在商事案件裁判中对合理商业目的、交易形式的尊重。基于这一典型案例可以看出,无论是循环贸易的增加业绩、融资、保障债权目的,还是其交易形式,都不足以否定合同的效力。尊重特殊的商业形式以及当事人的意思自治是今后相关案件裁判的应然路径。

关键词： 异质性   商贸流通业   先导性  

摘要： 本文综合采用趋势分析、时差相关性分析、格兰杰因果检验方法,就商贸流通业细分行业对我国国民经济发展作用进行再检验。研究发现:商贸流通业整体在我国经济中的先导性作用在长期逐步释放,且批发和零售业先导性强于交通运输、仓储和邮政业。

关键词： 贫血   鉴别诊断   血液检验   临床分析  

摘要： 目的研究血液检验在贫血类型的鉴别诊断中的发挥的作用。方法该院选择2013年3月—2015年3月间诊治的120例贫血患者,根据贫血类型将其分为两组,60例为溶血性贫血组,60例为缺铁性贫血组,同时选择60例正常的患者进行对比分析,对所选患者进行血细胞检测,比较3组患者血液中的红细胞(RBC)、平均红细胞容积(MCV)、血红蛋白(Hb)、平均红细胞血红蛋白(MCH)、红细胞分布宽度(RDW)等存在的差异,同时比较观察组的两组患者特异性、灵敏度以及符合率之间的不同。结果通过对3组患者进行比较,溶血性贫血组患者中的RBC明显比对照组低,缺铁性贫血组患者的Hb指标明显比对照组及溶血性贫血组患者低,而3组患者中,对照组患者的MCH最高,3组患者差异有统计学意义(P<0.05)。缺铁性贫血组及溶血性贫血组患者血液检测的特异度、灵敏度以及符合率差异无统计学意义(P>0.05)。结论通过血液检测能够分辨出一些贫血类型,通过比较简单方便的方法进行鉴别诊断,能够有效提升贫血的筛查诊断。

关键词： 产品包装   农业经济效益   令人惋惜   果形   水果市场   发泡塑料   优质大米   塑料编织袋   商标品牌   纸箱包装  

摘要： 改进农产品包装是提高农产品档次、开拓销售市场、提高农业经济效益的根本途径。每当收获的季节,我们经常看到橘子、柚子等水果堆放在路边,以低廉的价格出售,农民的辛勤劳动得不到应有的报酬,实在令人惋惜。相反,在城市大商场,水果柜上精心包装的洋水果却价格昂贵,销路很好。美国的"新骑士"

关键词： 基因-环境交互作用   素质-压力模型   不同易感性模型   优势敏感性模型  

摘要： 素质-压力模型、不同易感性模型和优势敏感性模型是当前有关基因-环境交互作用的三种代表性理论模型。素质-压力模型认为"近墨者黑"或"出淤泥而不染",优势反应敏感性模型认为"近朱者赤",而不同易感性模型则兼收并蓄,认为某些个体近墨则黑,近朱则赤。检验上述模型的现实有效性是当前基因-环境交互作用研究领域的热点问题之一。概观而言,分组回归和分层回归是常用的传统检验方法,显著性区域分析法和新参数回归模型法则是新近兴起的。未来研究需要进一步探索三种模型的领域特殊性、种族差异等问题,检验这些模型的方法也有待改善。

关键词： Social interaction   Social presence   Virtual environments   Avatar   Massively multiplayer online games   Immersion   TIME  

摘要： A behavioral observation methodology was employed in this study to examine how social behavior unfolds within a virtual environment and to identify what might perpetuate this behavior. Partial interval recording sampling was used to code social interactions (Socio-Spatial Interactivity and Social Presence) that occurred between experienced World of Warcraft players during their game play. Given the bidirectional nature of social interactions, Socio-Spatial Interactivity and Social Presence variables (Affective Association, Community Cohesion, Interaction Intensity, and Knowledge & Experience) were employed as both dependent and independent variables in two separate sets of regression analyses. Findings suggest that a positive feedback loop exists between Socio-Spatial Interactivity and Social Presence. Based on these findings, the researchers discuss implications for designers and end-users of virtual environments. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： BIODIVERSITY DATA   MODEL   INFORMATION   DATABASES   DIVERSITY   FRAMEWORK  

摘要： We present the model and implementation of a workflow that blazes a trail in systematic biology for the re-usability of character data (data on any kind of characters of pheno- and genotypes of organisms) and their additivity from specimen to taxon level. We take into account that any taxon characterization is based on a limited set of sampled individuals and characters, and that consequently any new individual and any new character may affect the recognition of biological entities and/or the subsequent delimitation and characterization of a taxon. Taxon concepts thus frequently change during the knowledge generation process in systematic biology. Structured character data are therefore not only needed for the knowledge generation process but also for easily adapting characterizations of taxa. We aim to facilitate the construction and reproducibility of taxon characterizations from structured character data of changing sample sets by establishing a stable and unambiguous association between each sampled individual and the data processed from it. Our workflow implementation uses the European Distributed Institute of Taxonomy Platform, a comprehensive taxonomic data management and publication environment to: (i) establish a reproducible connection between sampled individuals and all samples derived from them; (ii) stably link sample-based character data with the metadata of the respective samples; (iii) record and store structured specimen-based character data in formats allowing data exchange; (iv) reversibly assign sample metadata and character datasets to taxa in an editable classification and display them and (v) organize data exchange via standard exchange formats and enable the link between the character datasets and samples in research collections, ensuring high visibility and instant reusability of the data. The workflow implemented will contribute to organizing the interface between phylogenetic analysis and revisionary taxonomic or monographic work.

关键词： Nicotine   Phencyclidine   Reinforcement   Rats   Operant behavior   DRUG DISCRIMINATION   SMOKING   RATS   COCAINE   PCP   SCHIZOPHRENIA   REWARD  

摘要： Nicotine is a widely-abused drug, yet its primary reinforcing effect does not seem potent as other stimulants such as cocaine. Recent research on the contributing factors toward chronic use of nicotine-containing products has implicated the role of reinforcement-enhancing effects of nicotine. The present study investigates whether phencyclidine (PCP) may also possess a reinforcement-enhancement effect and how this may interact with the reinforcement-enhancement effect of nicotine. PCP was tested for two reasons: (1) it produces discrepant results on overall reward, similar to that seen with nicotine and (2) it may elucidate how other compounds may interact with the reinforcement-enhancement of nicotine. Adult male Sprague-Dawley rats were trained to lever press for brief visual stimulus presentations under fixed-ratio (FR) schedules of reinforcement and then were tested with nicotine (0.2 or 0.4 mg/kg) and/or PCP (2.0 mg/kg) over six increasing FR values. A selective increase in active lever-pressing for the visual stimulus with drug treatment was considered evidence of a reinforcement-enhancement effect. PCP and nicotine separately increased active lever pressing for a visual stimulus in a dose-dependent manner and across the different FR schedules. The addition of PCP to nicotine did not increase lever-pressing for the visual stimulus, possibly due to a ceiling effect. The effect of PCP may be driven largely by its locomotor stimulant effects, whereas the effect of nicotine was independent of locomotor stimulation. This dissociation emphasizes that distinct pharmacological properties contribute to the reinforcement-enhancement effects of substances. (C) 2015 Elsevier B.V. All rights reserved.