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B. G. C. Maisonneuve T. Honegger J. Cordeiro O. Lecarme T. Thiry D. Fuard K. Berton E. Picard M. Zelsmann D. Peyrade 《Biomicrofluidics》2016,10(2)
With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks. 相似文献
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Research in Higher Education - Since the turn of the twenty-first century, going to college has become increasingly financially difficult in the United States. Tuition prices continued to rise,... 相似文献
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A Campus-Wide Investigation of Clicker Implementation: The Status of Peer Discussion in STEM Classes
Justin D. Lewin Erin L. Vinson MacKenzie R. Stetzer Michelle K. Smith 《CBE life sciences education》2016,15(1)
At the University of Maine, middle and high school teachers observed more than 250 university science, technology, engineering, and mathematics classes and collected information on the nature of instruction, including how clickers were being used. Comparisons of classes taught with (n = 80) and without (n = 184) clickers show that, while instructional behaviors differ, the use of clickers alone does not significantly impact the time instructors spend lecturing. One possible explanation stems from the observation of three distinct modes of clicker use: peer discussion, in which students had the opportunity to talk with one another during clicker questions; individual thinking, in which no peer discussion was observed; and alternative collaboration, in which students had time for discussion, but it was not paired with clicker questions. Investigation of these modes revealed differences in the range of behaviors, the amount of time instructors lecture, and how challenging the clicker questions were to answer. Because instructors can vary their instructional style from one clicker question to the next, we also explored differences in how individual instructors incorporated peer discussion during clicker questions. These findings provide new insights into the range of clicker implementation at a campus-wide level and how such findings can be used to inform targeted professional development for faculty. 相似文献
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Ron Johnston David Manley Kelvyn Jones Richard Harris Anthony Hoare 《Higher Education Quarterly》2016,70(1):24-42
The United Kingdom's Department for Education has recently changed the nature of the AS‐level examinations normally taken by students aspiring to enter higher education degree courses one year into their post‐compulsory education. In the face of protests from universities and other institutions that this would both harm students’ progression towards the A‐level qualifications, on which entry to English universities is normally based, and make it difficult for universities determining which of their applicants were best placed to benefit from their degree courses, the Department conducted research which it claimed showed that degree outcome could be predicted as well from the results of GCSE examinations taken one year before AS‐levels as from AS‐levels themselves. This paper critiques those analyses and their conclusions showing, through a re‐analysis and extended interpretation of the Department's data, that AS‐levels provide a more reliable predictor of degree performance in 2011 than GCSEs and that many students who performed better at AS‐level than at GCSE gained a place, and performed well, at a university with high entrance standards. 相似文献
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