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Wong Kin Mun Khe Foon Hew Wing Sum Cheung 《British journal of educational technology : journal of the Council for Educational Technology》2009,40(5):848-860
Although a number of researchers have examined response pad systems (RPSs) in higher education, there has been very little research at the K-12 level. This paper investigated the impact of using an RPS in the learning of physics concepts in a secondary school in Singapore. Two classes ( n = 35 students in each class) of secondary five students participated in this study. One of the classes used an RPS while the other did not. Both classes completed a pretest and a posttest which tested the students in the application of the physics concepts taught. Results suggested that the class that used an RPS performed better in the posttest compared to the class that did not use the system. In addition, we explored the teacher and students' perceptions of using the RPS. 相似文献
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Attenuated performance during intense exercise with limited endogenous carbohydrate (CHO) is well documented. Therefore, this study examined whether caffeine (CAF) mouth rinsing would augment performance during repeated sprint cycling in participants with reduced endogenous CHO. Eight recreationally active males (aged 23?±?2?yr, body mass 84?±?4?kg, stature 178?±?7?cm) participated in this randomized, single-blind, repeated-measures crossover investigation. Following familiarization, participants attended two separate evening glycogen depletion sessions. The following morning, participants completed five, 6?s sprints on a cycle ergometer (separated by 24?s active recovery), with mouth rinsing either (1) a placebo solution or (2) a 2% CAF solution. During a fifth visit, participants completed the sprints without prior glycogen depletion. Repeated-measures ANOVA identified significant main effect of condition (CAF, placebo, and control [P?P?P?P?P?P?相似文献
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This study is concerned with the challenge of understanding what factors may influence students’ higher level knowledge construction.
We defined higher level knowledge construction occurrences as the sum of the number of phases II to V measured using Gunawardena
et al.’s (J Educ Comput Res 17(4):397–431, 1997) interaction analysis model. This paper is organized into two studies. In the first study, we examined the relationship between
the frequency of higher level knowledge construction occurrences and group size, as well as the duration of the online discussion.
Data were collected through online observations of 40 discussion forums. We found a significant positive relationship between
group size and the frequency of higher level knowledge construction occurrences. However, there was no correlation between
the duration of the online discussion and the frequency of such occurrences. In the second study, we examined the types of
student facilitation techniques used. A further analysis of the data was conducted—of the 40 forums, 14 forums with higher
incident rate of higher level knowledge construction occurrences were identified. Fourteen less frequent forums were then
randomly chosen from the remaining forums. We found significant differences in the frequency of four student facilitation techniques
employed between the more frequent group and the less frequent one. The results of this study suggest that using these four
techniques more frequently may promote knowledge construction in asynchronous online discussions. 相似文献
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We present a method capable of rapidly (∼20 s) determining the density and mass of a single leukemic cell using an optically induced electrokinetics (OEK) platform. Our team had reported recently on a technique that combines sedimentation theory, computer vision, and micro particle manipulation techniques on an OEK microfluidic platform to determine the mass and density of micron-scale entities in a fluidic medium; the mass and density of yeast cells were accurately determined in that prior work. In the work reported in this paper, we further refined the technique by performing significantly more experiments to determine a universal correction factor to Stokes'' equation in expressing the drag force on a microparticle as it falls towards an infinite plane. Specifically, a theoretical model for micron-sized spheres settling towards an infinite plane in a microfluidic environment is presented, and which was validated experimentally using five different sizes of micro polystyrene beads. The same sedimentation process was applied to two kinds of leukemic cancer cells with similar sizes in an OEK platform, and their density and mass were determined accordingly. Our tests on mouse lymphocytic leukemia cells (L1210) and human leukemic cells (HL-60) have verified the practical viability of this method. Potentially, this new method provides a new way of measuring the volume, density, and mass of a single cell in an accurate, selective, and repeatable manner. 相似文献
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Drawing on data generated by a two-year ethnographic study in a high security Spanish prison, this article explores the multiple meanings given to the social practices of sport and physical activity. We provide details of the following key themes that emerged from the analysis: (a) escaping time; (b) perceived therapeutic benefits; (c) social control; (d) gendered dimensions; and (e) performing masculinity. The findings suggest that a diverse and contradictory set of meanings are associated with sport and physical activity within this particular prison culture, and that the performance of specific kinds of masculinity is both a process and product that shapes the construction of experience in powerful ways. 相似文献