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41.
Educational technology research and development - In recent years, many psycho-educational technologies were studied to address the school-related difficulties encountered by students with autism...  相似文献   
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Science education studies have revealed that students often have misconceptions about how nature works, but what happens to misconceptions after a conceptual change remains poorly understood. Are misconceptions rejected and replaced by scientific conceptions, or are they still present in students' minds, coexisting with newly acquired scientific conceptions? In this study, we use functional magnetic resonance imaging (fMRI) to compare brain activation between novices and experts in science when they evaluate the correctness of simple electric circuits. Results show that experts, more than novices, activate brain areas involved in inhibition when they evaluate electric circuits in which a bulb lights up, even though there is only one wire connecting it to the battery. These findings suggest that experts may still have a misconception encoded in the neural networks of their brains that must be inhibited in order to answer scientifically.  相似文献   
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A number of studies have shown, counter-intuitively, that skilled adult readers find it difficult to correctly relate phonemes to graphemes in written words. In most adults this is of little consequence. However, teachers are required to show children how to relate phonemes to graphemes when teaching reading. This study investigated whether a brief period of instruction would improve the ability of adults in this task. Results showed a general level of improvement relative to controls. Exposure alone to the task had no effect. Improvement for the instructed group was not very large and there was difficulty relating phonemes to graphemes which had more than one letter. It may be that trainee teachers need instruction to improve knowledge of grapheme phoneme correspondence so that they can pass such knowledge onto young readers.  相似文献   
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Taking the present crisis of the Canadian Service of Admission to College and University as a starting point, the authors examine the history of SACU, which in 1971 was still a comparatively efficient organisation. Changes in the wider society, such as growing provincialism in Canada as well as stagnation or decline in enrolment together with a broader acceptance of the philosophy of open admission, have led to a drastic decline in the number of participants in the tests and to severe criticism of the predominantly selective function of SACU. It is felt that a reorientation of the testing activities of SACU should be in the direction of distributive and counselling functions, thus adopting the 1970 recommendations of the Commission on Tests of the American College Entrance Examination Board.  相似文献   
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We have developed a method for studying cellular adhesion by using a custom-designed microfluidic device with parallel non-connected tapered channels. The design enables investigation of cellular responses to a large range of shear stress (ratio of 25) with a single input flow-rate. For each shear stress, a large number of cells are analyzed (500–1500 cells), providing statistically relevant data within a single experiment. Besides adhesion strength measurements, the microsystem presented in this paper enables in-depth analysis of cell detachment kinetics by real-time videomicroscopy. It offers the possibility to analyze adhesion-associated processes, such as migration or cell shape change, within the same experiment. To show the versatility of our device, we examined quantitatively cell adhesion by analyzing kinetics, adhesive strength and migration behaviour or cell shape modifications of the unicellular model cell organism Dictyostelium discoideum at 21 °C and of the human breast cancer cell line MDA-MB-231 at 37 °C. For both cell types, we found that the threshold stresses, which are necessary to detach the cells, follow lognormal distributions, and that the detachment process follows first order kinetics. In addition, for particular conditions’ cells are found to exhibit similar adhesion threshold stresses, but very different detachment kinetics, revealing the importance of dynamics analysis to fully describe cell adhesion. With its rapid implementation and potential for parallel sample processing, such microsystem offers a highly controllable platform for exploring cell adhesion characteristics in a large set of environmental conditions and cell types, and could have wide applications across cell biology, tissue engineering, and cell screening.  相似文献   
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The aim of this case study was to determine whether a sailor's deliberate choice of a conservative strategy to manage sleep deprivation would allow him to cross the Pacific Ocean and to minimize his state of anxiety and perceived fatigue. The participant, who had more than 10 years' sailing experience in severe conditions, was tested on a small catamaran without any living quarters during a solo Pacific Ocean crossing. Estimations of sleep hours, state anxiety, and perceived fatigue were self-reported by the sailor on a daily basis using a specific questionnaire. The most important finding is that the sailor's deliberate sleep strategy, 5.4 h sleep per day (24% less than on-shore), was enough to keep his anxiety and perceived fatigue within acceptable limits and enabled him to achieve his goal, which was the first crossing of the Pacific Ocean on a catamaran of less than 6 m. In conclusion, our results suggest that the sailor observed in the present case study was able to minimize anxiety and perceived fatigue with adequate sleep to optimize his performance, security, and to achieve his goal.  相似文献   
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