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121.
Beverage-agarose gel electrophoresis: an inquiry-based laboratory exercise with virtual adaptation 总被引:1,自引:1,他引:0
A wide range of literature and experience has shown that teaching methods that promote active learning, such as inquiry-based approaches, are more effective than those that rely on passive learning. Gel electrophoresis, one of the most common laboratory techniques in molecular biology, has a wide range of applications in the life sciences. As such, we chose it as a platform to expose high school and undergraduate students to the active process of scientific inquiry in general, while specifically teaching electrophoresis. First, we optimized DNA electrophoresis in the laboratory by using common beverages instead of standard media (e.g., Tris-based media). Second, we adapted this laboratory process of progressive optimization to a Web-based format in which students had to achieve all the same steps of optimization by performing serial electrophoreses. And third, we evaluated the use of this entirely Web-based virtual laboratory exercise in high school and undergraduate biology courses. Students learned fundamental and practical principles of electrophoresis, while experiencing the essential inquiry-based process of optimizing a technique, and they also enjoyed it. Our findings provide a readily accessible, inexpensive, and intriguing technique for teaching electrophoresis and the progressive optimization of a laboratory technique. 相似文献
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Engineering is featured prominently in the Next Generation Science Standards (NGSS) and related reform documents, but how its nature and methods are described is problematic. This paper is a systematic review and critique of that representation, and proposes that the disciplinary core ideas of engineering (as described in the NGSS) can be disregarded safely if the practices of engineering are better articulated and modeled through student engagement in engineering projects. A clearer distinction between science and engineering practices is outlined, and prior research is described that suggests that precollege engineering design can strengthen children’s understandings about scientific concepts. However, a piecemeal approach to teaching engineering practices is unlikely to result in students understanding engineering as a discipline. The implications for science teacher education are supplemented with lessons learned from a number of engineering education professional development projects. 相似文献
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D Cunningham S Grefsheim M Simon P S Lansing 《Bulletin of the Medical Library Association》1991,79(1):45-52
The second part of the biotechnology awareness study focused on health sciences libraries and how well they are meeting the needs of biotechnologists working in the study's nine medical centers. A survey was conducted over a three-month period to assess the demand for biotechnology-related reference services at nine libraries and the sources the librarians used to answer the questions. Data on monographic and current serial holdings were also collected. At the end of the survey period, librarians were asked for their perceptions about biotechnology research at their institutions and in their geographic areas. Their responses were compared to the responses the scientists at the nine schools gave to the same or similar questions. Results showed few biotechnology-related reference questions were asked of the librarians. The recorded questions dealt with a range of biotechnology subjects. MEDLINE was used to answer 77% of the questions received during the survey period. More detailed notes in MeSH and a guide to online searching for biotechnology topics were suggested by the librarians as ways to improve reference service to this group of researchers. Journal collections were generally strong, with libraries owning from 50% to 87% of the titles on a core list of biotechnology journals compiled for this study. All libraries subscribed to the five titles most often cited by the scientists surveyed. Generally, librarians were unaware of the biotechnology-related research being done on their campuses or in their geographic areas. 相似文献
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