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.     

France: The National Centre for Distance Teaching

University Professor, Chief Education Officer and Director of the Centre National d'Enseignement à Distance (CNED) from December 1985 to December 1987. Author of several works on epistemology, history of science, social problems.     

Science achievement of english language learners in urban elementary schools: Results of a first‐year professional development intervention

This study is part of a 5‐year professional development intervention aimed at improving science and literacy achievement of English language learners (or ELL students) in urban elementary schools within an environment increasingly driven by high‐stakes testing and accountability. Specifically, the study examined science achievement at the end of the first‐year implementation of the professional development intervention that consisted of curriculum units and teacher workshops. The study involved 1,134 third‐grade students at seven treatment schools and 966 third‐grade students at eight comparison schools. The results led to three main findings. First, treatment students displayed a statistically significant increase in science achievement. Second, there was no statistically significant difference in achievement gains between students at English to Speakers of Other Language (ESOL) levels 1 to 4 and students who had exited from ESOL or never been in ESOL. Similarly, there was no significant difference in achievement gains between students who had been retained on the basis of statewide reading test scores and students who had never been retained. Third, treatment students showed a higher score on a statewide mathematics test, particularly on the measurement strand emphasized in the intervention, than comparison students. The results indicate that through our professional development intervention, ELL students and others in the intervention learned to think and reason scientifically while also performing well on high‐stakes testing. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 45: 31–52, 2008     

The Design of Competency-Based Performance Assessment in E-Learning

This article focuses on the design of competency-based performance assessment in e-learning. Though effort has been invested in designing powerful e-learning environments, relatively little attention has been paid to the design of valid and reliable assessments in such environments, leaving many questions to educational developers and teachers. As a solution to this problem, a systematic approach to designing performance assessments in e-learning contexts is presented, partly based on the 4C/ID model. This model enables the construction of realistic whole tasks instead of advocating education that is restricted to more isolated skills. A new assessment procedure also implies an alternative view of instructional design, learning and assessment. The requirements for the learning environment are addressed. Examples from a virtual seminar are presented to illustrate the design approach. The article concludes with the identification of possible pitfalls related to the approach and gives directions for future research.     

Modes of learning and profitability in Colombian and Mexican SMEs

The aim of this study is to analyze the effects of different modes of learning on innovation and profitability in SMEs in two Latin American countries; Mexico and Colombia. The data were obtained using a sample of 250 companies in the industrial sector operating in both countries. Results show that an integrated mode of learning based on internal and external knowledge supported by technological infrastructure have positive and significant effects on the degree of innovation and the profitability in SMEs However this effect appears to be not significantly different from the traditional SMEs mode of learning based mainly on market orientation.     

Achieving accurate metrics using balanced scorecards and dashboards

The balanced scorecard was developed to align business practices with the overall strategy of an organization and to monitor performance. A dashboard is a computer interface designed to receive and manipulate data from the various departments within a company to present comprehensive information to decision makers. The balanced scorecard, when combined with the dashboard, provides a way for organizations to determine strategy and evaluate performance.     

Peer Assessment Training in Teacher Education: Effects on performance and perceptions

The implementation of peer assessment receives much attention in teacher education. This paper reports the effects of peer assessment training on the performance of student teachers. Ninety-three student teachers were randomly assigned to control groups and experimental groups. The experimental groups were trained in defining performance criteria, giving feedback and writing assessment reports. This was done through peer assessment tasks that were embedded in a redesigned course. Analyses of data derived from peer assessment reports written by the students showed that the experimental groups surpassed the control groups in the quality of the assessment skill. As a result of the training, students from the experimental groups also scored significantly higher grades for the end products of the course than students from the control groups. The results of the questionnaire showed that all students were significantly more satisfied with the redesigned course.     

Effective practices for creating transformative informal science education programs grounded in Native ways of knowing

There are a growing number of informal science education (ISE) programs in Native communities that engage youth in science education and that are grounded in Native ways of knowing. There is also a growing body of research focusing on the relationship between culture, traditional knowledge, and science education. However, there is little research documenting how these programs are being developed and the ways in which culture and Western science are incorporated into the activities. This study outlines effective practices for using Native ways of knowing to strengthen ISE programs. These effective practices may also be used to promote change in formal education. The authors combine an overview of current research in informal science education with personal interviews with educators engaged in ISE programs offered to youth both on and off tribal reservations as well as experts in Indigenous education. Participating individuals and programs included Native communities across the United States, including Alaska and Hawai??i. Keeping in mind that each community is unique, ISE programs that are grounded in Native ways of knowing will benefit by utilizing the effective practices outlined here as a guide for starting or strengthening existing ISE programs relevant to the needs of their communities.     

The differential effects of task complexity on domain-specific and peer assessment skills

In this study the relationship between domain-specific skills and peer assessment skills as a function of task complexity is investigated. We hypothesised that peer assessment skills were superposed on domain-specific skills and will therefore suffer more when higher cognitive load is induced by increased task complexity. In a mixed factorial design with the between-subjects factor task complexity (simple, n?=?51; complex, n?=?59) and within-subjects factor task type (domain-specific, peer assessment), secondary school students studied four integrated study tasks, requiring them to learn a domain-specific skill (i.e. identifying the six steps of scientific research) and to learn how to assess a fictitious peer performing the same skill. Additionally, the students performed two domain-specific test tasks and two peer assessment test tasks. The interaction effect found on test performance supports our hypothesis. Implications for the teaching and learning of peer assessment skills are discussed.     

Understanding the effects of training programs for vulnerable adults on social inclusion as part of continuing education

According to the increasing rates of unemployment and poverty a significant share of the European population can be considered at-risk-of-social exclusion. In order to combat social exclusion adult education seemed to be a possible tool, which can increase social inclusion among adult learners. This study explores factors relating to training programs considered as adult and continuing education which enhance social inclusion for vulnerable adults and their life environment. The results indicate that after following the training programs as part of continuing learning, the participants show a significant increase in activation and internalisation as well as participation and connection (as processes of social inclusion). Moreover, non-parametric correlation analysis and logistical regression analysis shows that the training design feature transfer possibilities is significantly related to the increase of almost all social inclusion variables. Besides this direct surroundings and learning contents and activities only significantly relates to the increase of social inclusion variables of activation and internalisation and care to the social inclusion variables of participation and connection.