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Mohamed Moustafa Ali Robert Yager Esme Hacieminoglu Ilke Caliskan 《School science and mathematics》2013,113(3):109-119
This study focuses on two main issues concerning changes in student attitudes toward science study and their perceptions of its usefulness in their lives. Information has been gathered concerning how student attitudes toward science have changed for teachers and schools not involved with any funded professional development project. Pretesting and posttesting were administered with such “control” groups at the same intervals corresponding with the data collected from students with teachers enrolled in five funded Professional Development projects over the 1981–2008 interim. The grade levels used by the National Assessment of Education Progress in their 1977 assessment of science were used; it focused on students in grades 3, 7, and 11. The results indicate a steady decline in student positive attitudes concerning their science study as grade levels increase. Conversely, the student perceptions of the usefulness of their science study as related to daily living, further science study, and for potential careers remained much the same over the 30‐year interim is a second focus. Generally, results indicate that traditional teaching and major use of textbooks cause increasingly negative student attitudes about science while not producing major changes in their perceptions of its usefulness in their lives. 相似文献
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Visualizing macromolecular complexes with in situ liquid scanning transmission electron microscopy 总被引:1,自引:0,他引:1
Evans JE Jungjohann KL Wong PC Chiu PL Dutrow GH Arslan I Browning ND 《Micron (Oxford, England : 1993)》2012,43(11):1085-1090
A central focus of biological research is understanding the structure/function relationship of macromolecular protein complexes. Yet conventional transmission electron microscopy techniques are limited to static observations. Here we present the first direct images of purified macromolecular protein complexes using in situ liquid scanning transmission electron microscopy. Our results establish the capability of this technique for visualizing the interface between biology and nanotechnology with high fidelity while also probing the interactions of biomolecules within solution. This method represents an important advancement towards allowing future high-resolution observations of biological processes and conformational dynamics in real-time. 相似文献
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