A microfluidic device for on-chip agarose microbead generation with ultralow reagent consumption

Water-in-oil microdroplets offer microreactors for compartmentalized biochemical reactions with high throughput. Recently, the combination with a sol-gel switch ability, using agarose-in-oil microdroplets, has increased the range of possible applications, allowing for example the capture of amplicons in the gel phase for the preservation of monoclonality during a PCR reaction. Here, we report a new method for generating such agarose-in-oil microdroplets on a microfluidic device, with minimized inlet dead volume, on-chip cooling, and in situ monitoring of biochemical reactions within the gelified microbeads. We used a flow-focusing microchannel network and successfully generated agarose microdroplets at room temperature using the “push-pull” method. This method consists in pushing the oil continuous phase only, while suction is applied to the device outlet. The agarose phase present at the inlet is thus aspirated in the device, and segmented in microdroplets. The cooling system consists of two copper wires embedded in the microfluidic device. The transition from agarose microdroplets to microbeads provides additional stability and facilitated manipulation. We demonstrate the potential of this method by performing on-chip a temperature-triggered DNA isothermal amplification in agarose microbeads. Our device thus provides a new way to generate microbeads with high throughput and no dead volume for biochemical applications.     

Active relatives and health-related physical fitness in European adolescents: The HELENA Study

Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?相似文献   

Information literacy and library attitudes of occupational therapy students

Information literacy, often described as a person's ability to effectively find and evaluate answers to questions using a variety of information resources, is of particular importance to health care workers. This paper presents the results of an information literacy survey presented to occupational therapy (OT) students at Thomas Jefferson University during a series of required class activities. Also described are the authors' activities with the faculty and courses at Jefferson. The survey was made available to first-, second-, third-, and fourth-year occupational therapy students along with nursing students and pharmacy students. The survey is designed to identify research habits, skills, and preferences. Results confirm some commonly held perceptions about searching skills of young adults and an interesting dichotomy in students' learning habits. The paper concludes with a discussion of recommendations to OT faculty and librarians on how to improve information literacy education. The survey can be obtained by contacting the authors.     

Rivals for the crown: Reply to Opthof and Leydesdorff

We reply to the criticism of Opthof and Leydesdorff on the way in which our institute applies journal and field normalizations to citation counts. We point out why we believe most of the criticism is unjustified, but we also indicate where we think Opthof and Leydesdorff raise a valid point.     

A queer circle of friends,indeed! The school social as intervention or as movement

The purpose of this paper to present two approaches intended to support the social lives of those typically on the borders of school life. Circles of friends (CoFs) was designed to assist students labelled with disabilities, while Gay-straight alliances (GSAs) addresses needs of supporting students who identify as lesbian, gay, bisexual, transgender, two-spirited (gay/lesbian/bisexual First Nations people), queer and/or those questioning their sexual identity (LGBTTQQ). In laying out these approaches side by side, I argue that CoFs constitute a dis/abling pedagogy breed acquiescence, further pathologise students and create essentialised identification for all students. GSAs, in contrast, are constitutive of a queer pedagogy and promote active, agentive, healthy more complex identities. In short, CoFs are critiqued through GSAs and implications for inclusive schooling are explored.     

The Experiences of Selected Mentors: A Cross-cultural Examination of the Dyadic Relationship in School-based Mentoring

To address comprehensive program services that are self-sustaining and systemic in nature, school counselors and educational leaders have increasingly implemented school-based mentoring to impact student and school success. In this qualitative case study, we examined the experiences of 11 selected mentors and their respective dyadic relationships in school-based mentoring with at-risk elementary school students to understand ways mentors might better form closer dyadic bonds yielding longer mentoring relationships. Four metathemes emerged: (a) encouragement, (b) relating style, (c) time and presence, and (d) language nuances. Specific components within these metathemes increased both synergy in the dyad and satisfaction for the mentors. Ethnic and cultural dyad characteristics are discussed and presented via proposed effective practices for cross-cultural, cross-age mentoring.     

Situated Self-Regulation: Modeling the Interrelationships Among Instruction,Assessment, Learning Strategies and Academic Performance

To succeed academically, college students must actively construct course information, synthesize this information with information from texts and other resources, understand this information so that they can succeed on various forms of assessments and ultimately retain this information for the long term. While the complexity of these demands has been modeled somewhat metaphorically, there has been little ecologically valid research into learning in authentic classroom contexts. The present study examines the interrelationships among student perceptions of the learning context, test complexity, study strategies, and academic performance. Results of a path analysis demonstrated that perceptions of the teaching format and test complexity were positively related to the study strategies reported, and these study strategies were further related to the reported course performance.     

Voting Power on School Governing Boards: The Countenance of Proportionality

Acknowledging the realities and responsibilities of power is a precondition to using it wisely. The claim that there has been a shift in power away from the formal providers of education towards the individual consumer is one that needs closer investigation. This paper uses the mathematics of cooperative multiperson game theory to analyse the relative strengths of the various representative groupings on three different models of school governing bodies. Only a basic knowledge of mathematics is assumed as the various coalitions are analysed and compared, and conclusions drawn about the relative power of major and minor factions. Voting strategies, suggested payoffs for winning coalitions and implications for committee-forming are fully examined. The paper is based on the author's direct experience of school amalgamations in the border region of Ireland. An extended consideration of the theory of voting in multiperson games can be found in his book Decision-Making and Game Theory (2002, Cambridge University Press).     

A dynamic analysis of why learners develop a preference for autonomous learners in computer-mediated communication

A large number of studies in CMC have assessed how social interaction, processes and learning outcomes are intertwined. The present research explores how the degree of self-determination of learners, that is the motivational orientation of a learner, influences the communication and interaction patterns in an online Problem Based Learning environment. Given the complexity of CMC, we expected that autonomous learners would be more willing to contribute to cognitive discourse. In time, we expected that control-oriented learners would develop a preferential attachment to contribute to discourse from autonomous learners. Data were gathered from 37 autonomous and 39 control-oriented learners who posted 1669 messages. Using a dynamic multi-method approach of content analysis of cognitive and social discourse, social network analysis, and measures of academic motivation, we find some preliminary evidence that motivational orientation influences communication and social interaction patterns amongst learners. From the beginning, most control-oriented learners develop a preference to connect to and communicate with autonomous learners, although a separate team-analysis indicates that group dynamics also influence how learners develop connections with other learners in time. Our findings further the understanding of differences found in distance learning courses about participation and drop-out.     

Putting learning back into learning analytics: actions for policy makers,researchers, and practitioners

Educational technology research and development - This paper is based on (a) a literature review focussing on the impact of learning analytics on supporting learning and teaching, (b) a Delphi...