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71.
White B 《CBE life sciences education》2006,5(3):264-269
This article describes a simple and inexpensive hands-on simulation of protein folding suitable for use in large lecture classes. This activity uses a minimum of parts, tools, and skill to simulate some of the fundamental principles of protein folding. The major concepts targeted are that proteins begin as linear polypeptides and fold to three-dimensional structures, noncovalent interactions drive this folding process, and the final folded shape of a protein depends on its amino acid sequence. At the start of the activity, students are given pieces of insulated wire from which they each construct and fold their own polypeptide. This activity was evaluated in three ways. A random sample of student-generated polypeptides collected after the activity shows that most students were able to create an appropriate structure. After this activity, students (n = 154) completed an open-ended survey. Their responses showed that more than three-quarters of the students learned one or more of the core concepts being demonstrated. Finally, a follow-up survey was conducted seven weeks after the activity; responses to this survey (n = 63) showed that a similar fraction of students still retained these key concepts. This activity should be useful in large introductory-level college biology or biochemistry lectures. 相似文献
72.
Robert White 《Emotional and Behavioural Difficulties》2013,18(1):13-23
A sociocultural investigation with Year 8 secondary-school students experiencing marginalization and displaying signs of social and emotional difficulties in engaging fully with school life who participated in a mediated outdoor education programme was undertaken for this study. The findings indicate that there was a very statistically significant change in self-concept (p < 0.05) during the course of the programme. In addition, all participants reported positive results in relation to building trust, group cohesion, and emotional regulation with positive results on facing the challenges they experience daily within school. Moreover, 75% reported that they experienced positive gains in their family since beginning participation in the programme, and 100% stated that they had developed a deeper level of trust for the other group members. 相似文献
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James A. White Andria P. Troutman M. R. Chancey 《Technology, Pedagogy and Education》2013,22(1):79-89
ABSTRACT This study demonstrated how network usage logs such as those generated by the IBM Classroom Local Area Network Administration System (ICLAS) can be used to study student use of software available on a local area network. Software instrumentation was developed to convert ICLAS log files to a format (?.DIF) usable by spreadsheet and statistics software. Data on 163 students enrolled in an ‘Introduction to Computers in Education’ course during the Summer, 1992 session at the University of South Florida were compiled for exploratory analysis. Correlations of lab use time to course grade, change in knowledge, and change in attitude were performed. It was found that amount of lab use correlated significantly to general attitude toward computers, but that it did not correlate significantly to change in attitude toward school uses of computers or to change in knowledge of course topics. 相似文献
74.
Taran Cardone Elizabeth Stoll Turton Gerald Olson Marcia Baxter Magolda 《About Campus》2013,18(5):2-9
Committed to improving how their various programs serve student learning, Taran Cardone, Elizabeth Stoll Turton, Gerald Olson, and Marcia Baxter Magolda describe how their participation in Miami University's Community of Practice on Engaged Learning (COPEL) helped them create developmentally appropriate, learning‐centered approaches that support the complex task of student self‐authorship. 相似文献
75.
Xuan paper is a type of Chinese handmade paper produced for traditional calligraphy and painting in China since the Tang Dynasty (618–907 AD), and is therefore an important cultural heritage material. In this study, the fluorescence and photochemical properties of Xuan paper were investigated. Xuan paper exhibits auto-fluorescence in the blue spectral range (450–500 nm) and UVA photolysis of the paper resulted in a substantial reduction in the blue fluorescence together with the formation of chromophores absorbing in the visible spectrum, resulting in photoyellowing of the paper. A more significant yellowing of paper was observed when irradiated in the dry state than under wet conditions. The associated photogeneration of hydrogen peroxide and superoxide from three types of Xuan paper samples during irradiation showed a correlation between the yields of reactive oxygen species and their relative yellowing rates. The results are interpreted in terms of sensitised photooxidation via a mechanism of electron transfer involving the fluorophores in their excited singlet states being responsible for the photodegradation of Xuan paper. SEM/EDS analyses were performed on the Xuan paper samples to investigate their morphological and elemental characteristics. Silica-containing fibres characteristic of a special rice straw that grows in siliceous soil were observed in all types of Xuan paper. Micron-sized calcium precipitates possibly formed from the “lime-steaming” manufacture process were shown to protect against the acidification of paper during accelerated thermal ageing. 相似文献
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Conclusion The viewing of an educational film anf the recall of this viewing should constitute a satisfying learning experience so that
the film’s message will be incorporated into a useful store of vicarious experience and remembered facts. Such learning is
most likely to occur when those who write, direct, and edit a film have a clear understanding of the nature of the film’s
audience and of what the film is expected to do to this audience. Knowing these things and to present his subject matter in
the most interesting and satisfying manner possible.
Here a long-time writer of educational films and television programs presents some thoughtful ideas on the design of instructional
films for specific cudiences. Ralph R. White is a scenario writer with the Army Pictorial Center. 相似文献
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