Simulation of conformational preconditioning strategies for electrophoretic stretching of DNA in a microcontraction

We have used Brownian dynamics-finite element method to examine two conformational preconditioning approaches for improving DNA stretching in a microcontraction for the purpose of direct gene analysis. The newly proposed "pre-stretching" strategy is found to significantly improve the degree of DNA extension at the exit of the contraction. On the other hand, applying an oscillating extensional field to DNA yields no preconditioning effect. Detailed analysis of the evolution of DNA extension and conformation reveals that the success of our "pre-stretching" strategy relies on the "non-local" effect that cannot be predicted using simple kinematics analysis. In other words, accurate prediction can only be obtained using detailed simulations. Comparing to the existing preconditioning strategies, our "pre-stretching" method is easy to implement while still providing a very good performance. We hope that the insight gained from this study can be useful for future design of biomicrofluidic devices for DNA manipulation.     

A self-contained polymeric cartridge for automated biological sample preparation

Sample preparation is one of the most crucial processes for nucleic acids based disease diagnosis. Several steps are required for nucleic acids extraction, impurity washes, and DNA/RNA elution. Careful sample preparation is vital to the obtaining of reliable diagnosis, especially with low copies of pathogens and cells. This paper describes a low-cost, disposable lab cartridge for automatic sample preparation, which is capable of handling flexible sample volumes of 10 μl to 1 ml. This plastic cartridge contains all the necessary reagents for pathogen and cell lysis, DNA/RNA extraction, impurity washes, DNA/RNA elution and waste processing in a completely sealed cartridge. The entire sample preparation processes are automatically conducted within the cartridge on a desktop unit using a pneumatic fluid manipulation approach. Reagents transportation is achieved with a combination of push and pull forces (with compressed air and vacuum, respectively), which are connected to the pneumatic inlets at the bottom of the cartridge. These pneumatic forces are regulated by pinch valve manifold and two pneumatic syringe pumps within the desktop unit. The performance of this pneumatic reagent delivery method was examined. We have demonstrated the capability of the on-cartridge RNA extraction and cancer-specific gene amplification from 10 copies of MCF-7 breast cancer cells. The on-cartridge DNA recovery efficiency was 54-63%, which was comparable to or better than the conventional manual approach using silica spin column. The lab cartridge would be suitable for integration with lab-chip real-time polymerase chain reaction devices in providing a portable system for decentralized disease diagnosis.     

解析iSchools联盟发展现状与特色

从iSchools成员的分布、系所名称、博士班学程的特色,剖析iSchools成员的属性,以期能从中观察iSchools对资讯领域产生的影响。研究结果显示,目前iSchools 38个成员以美国为主,遍及欧、亚、澳各地,形成全球资讯学院联盟,有助于学术交流与合作。再者,其中有12个成员(占31.6%)来自ALA认可的学校,比例颇高,且其系所名称多单独使用资讯或资讯研究一词,传统的图书馆学系所在此已显式微。至于系所名称的表现,iSchools偏重资讯领域,有65.8%的系所名称以资讯一词起始、97.4%的系所名称涵盖资讯一词,显见资讯在此群组的主导性。最后,在人才培植方面,iSchools锁定资讯领域的高级学术、研究人才、企业界的高阶主管为目标,普设博士班学程,跨学科的课程以资讯为主体,强调科技应用。     

The Bumpy Road to Universal Access: An Actor-Network Analysis of a U.S. Municipal Broadband Internet Initiative

Universal high-speed Internet access can productively transform a nation's economy. However, many municipalities in the United States have been left behind in terms of Internet penetration. Some municipal governments have tried to address this by launching initiatives that aim at offering citywide, universal broadband access. Unfortunately, most of these initiatives either have been discontinued or have ended in failure. Drawing on actor-network theory, we conducted a 3-year study to investigate the evolution of the Internet TV initiative in LaGrange, Georgia, in the United States. The results reveal distinct interpretations of the initiative by different actor groups (the government, the service providers, socioeconomically advantaged residents, and socioeconomically disadvantaged residents), at different stages of implementation, pointing to tensions among the various groups. These tensions reflect the structural problems embedded in the macro political, economic, and societal context. The findings offer insights for policymakers who intend to achieve universal broadband access.     

Which is more influential on teaching practice,classroom management efficacy or instruction efficacy? Evidence from TALIS 2018

Asia Pacific Education Review - This study aims to explore relationship between teacher self-efficacy and teacher teaching practice in junior high schools at Taiwan. TALIS (2018) survey database is...     

现代教育的重要性与一流人才的培养

一种教育方式注定只适合培养一类人；一种评价体制注定只让一部分人“脱颖而出”：一种教育理念必定会扼杀一部分天才。教育应当是全方位的，不可忽视学习者的多元智能，否则教育就是在生产偏瘫产品。     

A Model for Developing and Testing Custom-Made Laboratory Manuals to Use with Food Chemistry and Food Analysis Courses

ABSTRACT: This project reports on a model for preparing food chemistry and food analysis laboratory manuals that provide a closer link between lecture material and laboratory exercises. Teaching effectiveness was also improved by evaluating the composition and eliminating duplication between these complementary courses. Utilizing the combination of personal experience and the scientific literature, laboratory exercises were developed and modified to fit with the lecture material. Labs were initially performed and critiqued by a graduate student. After making appropriate revisions, undergraduate students tested the labs under the graduate student's supervision and completed a questionnaire about their experiences. Based on the undergraduate feed-back, final revisions were made and custom laboratory manuals were printed. This project demonstrates one effective way for developing custom food science labs to parallel with lecture material.     

Exploring the role of flow experience,learning performance and potential behavior clusters in elementary students' game-based learning

Well-designed game-based learning can provide students with an innovative environment that may enhance students' motivation and engagement in learning and thus improve their learning performance. The purpose of this study was to examine the relationships among elementary school students' flow experience and learning performances. We also investigated the gender and grade differences as well as the types of potential clusters of flow experiences and performance. Thirty-four elementary school students participated in this study. This study conducted correction analysis, difference analysis and a two-stage cluster analysis. The findings suggested that the students with higher flow experiences tended to have higher learning performances. The results of gender differences showed that female students had high performance scores and great flow experiences in the mini-educational game in this study. Moreover, the results revealed that the students of higher grade had significantly higher scores in both performance and flow experience than the students of lower grade. The result of cluster analysis fell into three categories: low performance/low flow experience students, high flow experience students and high performance/high flow experience students. On the basis of our findings, we also proposed suggestions for future game-based learning research.