A Review of Methods for Missing Data

This paper reviews methods for handling missing data in a research study. Many researchers use ad hoc methods such as complete case analysis, available case analysis (pairwise deletion), or single-value imputation. Though these methods are easily implemented, they require assumptions about the data that rarely hold in practice. Model-based methods such as maximum likelihood using the EM algorithm and multiple imputation hold more promise for dealing with difficulties caused by missing data. While model-based methods require specialized computer programs and assumptions about the nature of the missing data, these methods are appropriate for a wider range of situations than the more commonly used ad hoc methods. The paper provides an illustration of the methods using data from an intervention study designed to increase students’ ability to control their asthma symptoms.     

工科设计专业校外实训基地建设和思考——以北京林业大学工业设计专业为例

现阶段校企合作是培养应用创新型人才的有效途径,因此校外实训基地是校企深度合作的基础。分析了工科背景下工业设计专业本科教育校外实训基地对应用创新人才培养的现状和意义,探讨了如何在现有校企合作的基础上,建设符合办学思想,有效提高本科学生的应用创新能力,提高就业竞争力的校外实训基地,并且通过一系列实践,提出了进一步加强实训基地建设的建议。     

时代背景、译入语文化及译者对译本的制控

翻译对当今国际全球化以及人类文明的发展起到了举足轻重的作用。作为语言传递的工具,很长时间内,翻译研究仅停留在语言层面上。然而,在翻译过程中,诸多因素会对译本造成影响,该文旨在分析以下三要素对译本的制控：翻译的时代背景、译入语文化以及译者。     

《儿子与情人》和《母亲大人》中畸形母爱的对比研究

《儿子与情人》和《母亲大人》这两部小说中的母亲都为儿子表现出了极端的畸形的母爱。本文通过比较社会背景,不幸婚姻和自身欲望等因素,分析这两部作品中畸形母爱的深层根源。     

Cowboy探源与演绎

牛仔是美国的代名词,"牛仔精神"被称为美国精神,就连布什政府的对外政策也被为牛仔政策.从牛仔一词探源入手,纵观美国历史,认为牛仔的表象是男人气概,而实质上,美国牛仔的外衣下包藏着野性和血腥的美国精神.由此也不难理解现在的"牛仔政策"了.     

浅谈文学翻译的几个原则

英语中文学的翻译有别于其它文体的翻译，须注意以下几个原则：熟谙原语的背景知识，尊重原民族文化个性，透视原作意图．     

语言风格得体的文化探析

文章着重论述了语言得体的文化渊源和制约语言得体的文化背景因素 ,以期有助于更好地理解和把握语言得体的文化内涵     

“语次传递”的运用——以马克·吐温和艾德加·爱伦·坡的两篇小说的开头为例

“语次传递”（transitivity）表示句子里的一种动性趋势的传递,它是通过句子里的三个主要因素,即事态、参与者和事态环境表示出来。研究某作家作品的特点时,既可以从故事情节、人物塑造、主题思想等方面入手,又可以通过对作家选择和安排事态、事态参与者和事态环境的特点追行研究,分析它们封作品背景、故事情节的叙述、气氛和基调的建立、人物形象的塑造和作品主题的表达所起的作用。本文试用“语次传递”理论,分析两篇小说的开头并讨论作家是如何在这三个因素之间作恰当地选择和安排,为小说的背景、气氛和基调主题服务。     

Three-dimensional tracking of GLUT4 vesicles in TIRF microscopy

TIRF microscopy has provided a means to view mobile granules within 100 nm in size in two dimensions. However quantitative analysis of the position and motion of those granules requires an appropriate tracking method. In this paper, we present a new tracking algorithm combined with the unique features of TIRF. Firstly a fluorescence correction procedure was processed to solve the problem of fluorescence bleaching over time. Mobile granules were then segmented from a time-lapse image stack by an adaptive background subtraction method. Kalman filter was introduced to estimate and track the granules that allowed reducing searching range and hence greater reliability in tracking process. After the tracked granules were located in x-y plane, the z-position was indirectly inferred from the changes in their intensities. In the experiments the algorithm was applied in tracking GLUT4 vesicles in living adipose cells. The results indicate that the algorithm has achieved robust estimation and tracking of the vesicles in three dimensions.     

初解美国——美国英语中的隐喻

本文从对大量已完全失去原有单词含义的美国英语日常用语分析理解入手，既让读者从一个侧面了解了美国英语的丰富多彩，又说明了语言并不是单一的技能训练。只有了解所学语言及其国家相关的文化和背荣知识，才能消除文化差异带来的语言障碍，从容跨过文化沟。