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关键词： 沙生植物   水分提升   土壤水分再分配   科尔沁沙地  

摘要： 对科尔沁沙地21种植物开展了水分提升作用检测和发生特点研究。试验采用上下层土壤隔离的自制栽植箱,通过控制上、下层土壤水分含量的方法检测植物水分提升作用。结果表明:有19个参试物种观测到水分提升作用,水分提升作用可能是沙生植物适应干旱环境的普遍特性;植物水分提升作用在00:00-06:00时段内发生频率和提升数量较高;不同物种间水分提升能力存在差异,本研究首次采用每克根系生物量(干质量)24h可产生的水分提升数量作为比较植物水分提升能力的单位,其数值变化范围为4.86～325.62g/g之间,平均为72.9g/g。综合比较认为,乌丹蒿、万年蒿、牧马豆和雾冰藜具有较强的水分提升能力。浅层土壤干旱程度与累计水分提升数量在统计学分析上并未表现出明显的相关性。利用植物水分提升能力改善固沙植被区浅层土壤水分环境条件,对提高半干旱区人工固沙植被的稳定性具有重要意义。

关键词： 不真正连带责任   违约赔偿责任   合同关系   注意义务   善良管理人   行业惯例   法律服务   过错程度  

摘要： 【裁判要旨】在有偿委托律师草拟合同、代办抵押的合同关系中，应认定律师承担专业的善良管理人的注意义务，并应结合案件实际情况和法律服务的行业惯例确认律师是否尽到了该注意义务。在确定律师承担违约赔偿责任的数额时，可以根据过错程度和原因力比例对传统的不真正连带责任进行份额化处理，以避免出现显失公平的结果。

关键词： 医疗仪器公司   售后服务   响应体系   客户价值  

摘要： 医疗仪器行业是为医院及医疗机构提供其使用的用于检验、治疗、警示、辅助护理等仪器或设备的生产及销售机构。医疗仪器既包括单独或者组合使用于人体的仪器、设备、器具、材料或者其他物品，也包括保证运行所需要的各种软件。医疗仪器行业的行业特点、发展趋势及可持续发展的需求对其售后服务体系的建设与完善提出了更高的要求。\n BC公司是以生产销售、提供技术服务的免疫检验，生化，血球检验等医疗检验仪器为主的美国公司，具有较高的市场占有率和知名度。随着BC公司产品在国内医疗部门的使用频率的提高，医生或医学研究人员对其依赖性也越来越大，因此，提供良好的售后服务，保障仪器的正常运转，对医疗人员工作成绩和相应医疗机构的长期效益均有深远的影响。同时根据价值链理论，一方面公司售后服务的质量与层级影响着医疗仪器企业的利益和长期发展，另一方面，客户对公司的售后服务要求越来越高，如响应速度、服务效率、服务质量、售后支付的费用、解决问题的能力等来满足仪器正常运行。如果诸如此类的售后服务问题不能得到圆满解决，给企业客户价值和客户关系造成严重的负面影响。\n 随着行业的发展，原来的售后服务体系已经不能满足企业和客户日益扩张的要求，为了能够更好的为客户提供高质量快速的售后服务，B公司在探索一条在原来的基础上更大程度提高售后服务的质量、效率、达到客户的满意及提高客户价值的途径。BC公司采取的策略是在原来的售后服务体系基础上，引入Helpdesk叫修平台理论，与公司的实际情况相结合。售后服务的工作统一由叫修平台来完成售后服务的统一调配，资源配置，人员调配等，在原来的流程上进行适当的修改，使得叫修平台成为整个售后服务响应体系的支点。作为售后服务响应体系中的重要成员，Helpdesk是帮助用户解决问题的一个在线技术支持平台，由经过培训的资深技术人员担任此职位，来接听客户电话，解决问题，收集信息，维持客户关系，协助配置资源，帮助客户实现其价值。\n 在售后服务响应体系加入Helpdesk后，运用SAP，CRM，Extranet等系统为Helpdesk提供了一个良好的操作平台。将技术人员的工作量进行适当的安排，使客户能够得到及时满意的服务，同时Helpdesk对技术数据库利用，极大的节省了客户和技术人员的时间，也因为Helpdesk运用使得售后服务变得更加快速、有效。Helpdesk通过售后服务响应体系的数据库处理客户提出的不同要求，发现及有效的解决各种出现的问题，以此来改善客户关系，提高信息系统支持能力，降低了因为资源不足，配置不合理引起的客户投诉和不满，提高客户价值。通过运行Helpdesk在客户回访，客户投诉调查等多方面运行，利用Helpdesk发展和保持客户关系。综合利用信息系统提高服务，更大程度的为客户着想，共同谋求更大的客户价值。通过对Helpdesk加入售后服务体系的运行，体现出运行helpdesk对售后服务响应体系的支持具有有效性。\n 在售后服务体系中首先从运行Helpdesk的必要性出发，将Helpdesk在医疗仪器企业售后服务体系的运行与维护中的积极作用进行了概述。运行好Helpdesk的售后服务体系是为客户创造价值的基础;Helpdesk的利用是完全符合服务特性，并体现出针对医疗仪器售后的独特性。Helpdesk对人力和物力的调配控制，也符合项目配置的必要性和基本条件。通过Helpdesk对客户的电话技术支持、客户电话回访等加深与客户的联系和沟通，良好的保持和发展了客户关系。其对信息支持系统的利用大大节约了时间和人力成本、满足了多数客户对时间和效率的严格要求，良好的客户关系最终的目的是为了实现客户价值。通过对实例的研究，即实证研究;具体论述医疗器械行业售后服务体系的运行规律与特点，并详细论述Helpdesk的特性及对医疗仪器售后服务体系的改善效果，以及资源的配置利用;结合成功案例中对信息系统的利用而表现出的不同优势;上述的影响，主要体现在对客户关系的改善与提升，最终的目的是为了实现客户价值，同时辅以成功案例加以进一步论证Helpdesk的应用对实现客户价值的积极作用;说明了运行Helpdesk对售后服务的有效支持作用。最后对系统本身的不足进行了客观的讨论，并针对其缺陷提出了解决方案，以进一步完善基于Helpdesk的售后服务响应体系建设。\n 总之，以医疗器械行业售后服务体系的建设与完善为背景，以BC公司的实际案例为基础，通过比较分析Helpdesk应用前和应用后的售后服务效果，得出Helpdesk的运用使售后服务响应体系变得更加有效，解决问题响应快速，客户利益得到保证，从而认定Helpdesk应用的必要性。同时，全面客观的分析了helpdesk本身的不足并提出解决方案，进一步揭示出更加有效的运行Helpdesk应该具有的特征、能

关键词： 国际贸易   计价货币   国际结算   模型构建  

摘要： 2007-2008年美国次债问题引发的全球性金融危机给全球金融稳定和全球经济增长造成巨大冲击，以美元为主导的国际货币体系遭遇挑战。事实表明，改革当前以美元为主导的国际货币体，势在必行。改革当前的国际货币体系，需要打破美元在现行体系中的霸权地位，全面推进国际货币体系多元化。因此，目前世界上多个国家或经济体开始相继推动本币的国际化步伐。\n 货币国际化的进程通常分为三个层次：首先是本币在一般国际经济交易中被广泛地用来计价结算;其次是本币在外汇市场上被广泛用作交易货币；最后是成为各国外汇储备中的主要货币之一。由此可见，货币在国际贸易中用于计价结算是其国际化的基础。因此，深入系统地理解国际贸易中计价货币的选择，这对一国货币实现国际计价结算和国际化都具有重要意义。本文从理论和实证两个层面研究国际贸易中计价货币选择的影响因素，以期为一国货币实现国际计价结算和实现货币国际化提供政策建议。\n 本文的研究具体分为六章：第一章，首先讨论了文章的选题背景和意义，然后通过对已有研究成果进行文献综述，最后阐述本文的研究框架、贡献和不足；第二章，首先定义国际贸易中计价货币的基本概念，然后对国际贸易中计价货币选择影响因素的一系列理论基础进行阐述；第三章，从厂商的利润最大化的视角出发，构建了国际贸易计价货币选择的理论模型，进行深入的理论研究；第四章，使用计量工具对国际贸易中计价货币选择的影响因素进行实证研究；第五章，在前面章节理论和实证分析结果的基础上，为一国货币在国际贸易中被广泛的用于计价货币提供政策建议；第六章是结语。\n 本文通过理论和实证研究表明，汇率制度、区域性汇率安排、货币自由兑换性、汇率波动性、出口商市场垄断程度、出口品需求价格弹性都是影响国际贸易中计价货币选择的重要因素。因此，如果一国货币要在国际贸易中广泛运用，进而实现国际化，就必须要实行合理的汇率制度，完善汇率的形成机制，完成资本与金融项目的开放，实现货币完全自由兑换，同时还要增强该国在国际市场上的地位，优化出口产品的产品结构，扩大对外贸易规模。

关键词： 商品检验   生鲜食品   加工配送中心   食品安全  

摘要： 近年来食品安全问题频发,引发了消费者对食品安全的忧虑与高度关注。生鲜食品是人们日常消费量最大的食品种类,随着消费水平的提高、生活节奏的加快,以及公众食品安全意识的提高,目前超市已经成为生鲜食品最重要的零售渠道。因此,为超市提供加工配送服务的生鲜加工配送中心不但是生鲜食品供应链中的重要一环,而且也是保障超市生鲜食品安全、卫生的关键。加强生鲜加工配送中心的商品检验能力,不仅可以起到保障食品安全的作用,同时还可以优化资源配置、提高检验水平、保证检验质量、减少重复检验,提高生鲜食品的流通效率。

关键词： Nutrition   Photoblastic   Rhizoid   Seed physiology   Seedling development  

摘要： The effects of carbohydrate availability, carbohydrate source, nutrient availability and illumination on germination and early development of Bletia purpurea (Orchidaceae) seeds were investigated using asymbiotic seed germination. Of special interest was determining the minimum nutritional and light requirements for the completion of germination. Germination and development was limited when seeds were cultured in darkness without sucrose. Seeds were able to germinate under illuminated conditions even in the absence of sucrose and this effect was enhanced when mineral nutrients were incorporated into media. Sucrose, fructose, glucose and trehalose enhanced germination and seedling development while mannitol and sorbitol did not. These data suggest that carbohydrates, either as products of photosynthesis, from symbiotic fungi in situ or as exogenously supplied sugars in vitro, play an important role in regulating seed germination by fulfilling an energy requirement. This hypothesis has been often expressed but rarely satisfactorily tested. Mineral nutrients appear to be less important for germination than carbohydrates. The differential effect of sucrose, fructose, glucose and trehalose at two different concentrations on rhizoid production indicates carbohydrates may play a role in regulating rhizoid production.

关键词： Substance first use   Age at first consumption   Taxonomy   Consumption profile   Classification  

摘要： The use of multiple legal and illegal substances by adolescents is a growing concern in all countries but since no consensus about a taxonomy did emerge yet it is difficult to understand the different patterns of consumption and to implement tailored prevention and treatment programs directed towards specific subgroups of the adolescent population Using data from a Swiss survey on adolescent health we analyzed the age at which ten legal and Illegal substances were consumed for the first time ever by applying a method combining the strength of both automatic clustering and use of substance experts Results were then compared to 30 socio-economic factors to establish the usefulness of and to validate our taxonomy We also analyzed the succession of substance first use for each group The final taxonomy consists of eight groups ranging from non consumers to heavy drug addicts All but four socio-economic factors were significantly associated with the taxonomy the strongest associations being observed with health behavior and sexuality factors Numerous factors influence adolescents in their decision to first try substances or to use them on a regular basis and no factor alone can be considered as an absolute marker of problematic behavior regarding substance use Different processes of experimentation with substances are associated with different behaviors therefore focusing on only one substance or only one factor is not efficient Prevention and treatment programs can then be tailored to address specific issues related to different youth subgroups (C) 2010 Elsevier Ltd All rights reserved

关键词： Nearest neighbor   Sample weighting   Loss function   Large margin  

摘要： The nearest neighbor classification is a simple and yet effective technique for pattern recognition. Performance of this technique depends significantly on the distance function used to compute similarity between examples. Some techniques were developed to learn weights of features for changing the distance structure of samples in nearest neighbor classification. In this paper, we propose an approach to learning sample weights for enlarging margin by using a gradient descent algorithm to minimize margin based classification loss. Experimental analysis shows that the distances trained in this way reduce the loss of the margin and enlarge the hypothesis margin on several datasets. Moreover, the proposed approach consistently outperforms nearest neighbor classification and some other state-of-the-art methods. (c) 2010 Elsevier B.V. All rights reserved.

关键词： Polymerized triacylglycerides (PTG)   Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR)   Partial least squares-discriminant analysis (PLS-DA)   Partial least squares (PLS) regression  

摘要： The selection of an appropriate calibration set is a critical step in multivariate method development. In this work, the effect of using different calibration sets, based on a previous classification of unknown samples, on the partial least squares (PLS) regression model performance has been discussed. As an example, attenuated total reflection (ATR) mid-infrared spectra of deep-fried vegetable oil samples from three botanical origins (olive, sunflower, and corn oil), with increasing polymerized triacylglyceride (PTG) content induced by a deep-frying process were employed. The use of a one-class-classifier partial least squares-discriminant analysis (PLS-DA) and a rooted binary directed acyclic graph tree provided accurate oil classification. Oil samples fried without foodstuff could be classified correctly, independent of their PTG content. However, class separation of oil samples fried with foodstuff, was less evident. The combined use of double-cross model validation with permutation testing was used to validate the obtained PLS-DA classification models, confirming the results. To discuss the usefulness of the selection of an appropriate PLS calibration set, the PTG content was determined by calculating a PLS model based on the previously selected classes. In comparison to a PLS model calculated using a pooled calibration set containing samples from all classes, the root mean square error of prediction could be improved significantly using PLS models based on the selected calibration sets using PLS-DA, ranging between 1.06 and 2.91% (w/w).

关键词： Photosynthesis   Evolution   Reaction center   Tyrosine oxidation   Manganese   Oxygen-evolving complex   Rhodobacter sphaeroides   Purple bacteria  

摘要： In photosynthetic organisms, such as purple bacteria, cyanobacteria, and plants, light is captured and converted into energy to create energy-rich compounds. The primary process of energy conversion involves the transfer of electrons from an excited donor molecule to a series of electron acceptors in pigment-protein complexes. Two of these complexes, the bacterial reaction center and photosystem II, are evolutionarily related and structurally similar. However, only photosystem II is capable of performing the unique reaction of water oxidation. An understanding of the evolutionary process that lead to the development of oxygenic photosynthesis can be found by comparison of these two complexes. In this review, we summarize how insight is being gained by examination of the differences in critical functional properties of these complexes and by experimental efforts to alter pigment-protein interactions of the bacterial reaction center in order to enable it to perform reactions, such as amino acid and metal oxidation, observable in photosystem II.