Isolation and manipulation of living adherent cells by micromolded magnetic rafts

A new strategy for magnetically manipulating and isolating adherent cells with extremely high post-collection purity and viability is reported. Micromolded magnetic elements (termed microrafts) were fabricated in an array format and used as culture surfaces and carriers for living, adherent cells. A poly(styrene-co-acrylic acid) polymer containing well dispersed magnetic nanoparticles was developed for creating the microstructures by molding. Nanoparticles of γFe(2)O(3) at concentrations up to 1% wt.∕wt. could be used to fabricate microrafts that were optically transparent, highly magnetic, biocompatible, and minimally fluorescent. To prevent cellular uptake of nanoparticles from the magnetic polymer, a poly(styrene-co-acrylic acid) layer lacking γFe(2)O(3) nanoparticles was placed over the initial magnetic microraft layer to prevent cellular uptake of the γFe(2)O(3) during culture. The microraft surface geometry and physical properties were altered by varying the polymer concentration or layering different polymers during fabrication. Cells plated on the magnetic microrafts were visualized using standard imaging techniques including brightfield, epifluorescence, and confocal microscopy. Magnetic microrafts possessing cells of interest were dislodged from the array and efficiently collected with an external magnet. To demonstrate the feasibility of cell isolation using the magnetic microrafts, a mixed population of wild-type cells and cells stably transfected with a fluorescent protein was plated onto an array. Microrafts possessing single, fluorescent cells were released from the array and magnetically collected. A post-sorting single-cell cloning rate of 92% and a purity of 100% were attained.     

Fútbol para Todos (Soccer for All): Democratization,Populist Legitimization or Quasi-Authoritarianism?

Abstract

In 2009 the Argentine government of Cristina Fernández de Kirchner created Fútbol para Todos (Soccer for All), a programme that led to a policy of direct state intervention in the acquisition of government television rights for the transmission of soccer matches throughout Argentina. Does Fútbol para Todos serve as a tool for the democratization of Argentinean society, a strategy for populist legitimization, or as an embodiment of quasi-authoritarianism? Successive Argentine governments have politicized soccer. Fútbol para Todos has served as a tool for populist legitimization, but also as a strategy designed to legitimize state interference in a historically private domain, promote government propaganda through a new state monopoly, and strengthen governance processes through popular approval under the ambit of the ‘democratization’ slogan. Fútbol para Todos thus aims to use the state as an agent in the construction of better governance processes for all, but it also reinforces the historical union between soccer and establishment political power in Argentina. Fútbol para Todos is populist in tone and appears democratic, but also masks a darker undercurrent of quasi-authoritarian tendencies in Argentina.     

湘南地区农村居民收入与消费问题的调查研究

通过实地走访和问卷调查,并以湘潭市的数据作为参照,对比分析了湘南地区农民收入来源和消费结构现状;针对湘南地区农村居民收入与消费存在的主要问题以及消费的影响因素,从提高农民收入、提升人力资本水平、改善农村消费环境和基础设施、构筑与完善农村现代金融服务体系几个方面提出了解决途径。     

高校创新型科研团队建设的认识误区及对策

高校创新型科研团队建设有利于我国高校创新整体水平的提高、创新效率的增强、创新合作与竞争的协调.传统观念的错位理解、诸多主义思潮与内蕴精神的缺失等是严重制约我国高校创新型科研团队建设的认识误区.通过对这些不利因素分析,为高校创新型科研团队建设提出相应的对策思路.     

The effect of the biology critical thinking project on the development of critical thinking

This article describes the Biology Critical Thinking (BCT) project in which carefully designed activities for developing specific critical thinking skills are incorporated into the biology curriculum. The objectives were to find out whether the BCT project contributes to the development of critical thinking skills in various biological and nonbiological topics and how it affects students' biological knowledge and classroom learning environment. The study consisted of 678 seventh graders who were assigned randomly into two groups that studied the same seventh-grade biology textbook. Only one group, the experimental, completed the BCT activities. The results indicate that the students in the experimental group improved their critical thinking skills compared to their own initial level and compared to their counterparts in the control group. Improved critical thinking skills were observed in a new biological context and nonbiological everyday topics, suggesting generalization of thinking skills across domains. The experimental students scored significantly higher than the control on a knowledge test, suggesting that “knowledge of facts” as one educational goal and “learning to think” as another, need not conflict, but rather can interact with each other. Finally, the results show that BCT involvement decreased the frequency of teacher-centered teaching and enhanced student-centered, more active learning.     

Cognitive preferences: A validation study

In 1964 Health introduced the cognitive preference construct and used it to evaluate a new science curriculum. Since then the construct, adapted from research on cognitive styles, has been used in many research and evaluation studies. More recently, however, a number of questions have been raised concerning the validity of findings and analytical techniques employed in these studies. Ultimately the validity of the cognitive preference construct itself is being questioned.In this article a framework for examining validity evidence for the cognitive preference construct is developed; the literature on cognitive preferences in the context of this framework is reviewed, and the validity evidence developed in one recent study is presented and discussed.     

Considering the role of invitations to inquiry in scienceteaching and in teacher education

Conclusion Invitations to inquiry have been shown to be not only an interesting and effective way of teaching science as inquiry by inquiry, but also as a highly effective means for teacher education. It is recommended that institutions which employ the classic model of microteaching (Allen and Ryan, 1969) revise their approach and adopt a more holistic approach such as the one described here. This article is dedicated to the memory of Dr. Joseph J. Schwab, a master of science teacher education and a curriculum scholar whose ideas continue to illuminate classroom practice.     

个性化教育的研究与实践

对学校后勤人员的考核方法，一般来讲有三种：一种是定性考核，一种是定量考核，一种是两的结合。我们提出的量化测评办法，是指对被考核所设置的考核指标，除无法量化的少部分内容采用否决限制外，使定性考核所得的等级转化为定量化，从而与定量考核融为一体，使被考核的工作业绩明晰而确定。量化测评办法在考核学校后勤人员工作中的运用，意在使考核工作更具简洁性、可操作性、现实性和科学性。