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991.
Case studies have been used successfully as a part of teacher education. There are many possibilities in extending the impact of case studies through the use of technology. Video and the Internet could enable demonstration of more examples, dissemination beyond the walls of the classroom, and discussion between geographically dispersed preservice teachers. Several projects are now investigating the possible ways that technology might enhance or extend text case studies. After exploring four existing products, four essential elements for video case studies are proposed. As video case studies move to the Internet, additional issues arise and these are also explored. 相似文献
992.
993.
Michael Silver Chad R. Lochmiller Michael A. Copland Ann Marie Tripps 《Mentoring & Tutoring: Partnership in Learning》2013,21(3):215-232
Administrators need intense support in their early years in their jobs to master the demands of the position and to emerge as effective leaders for their schools. This article reports on a leadership coaching program offered by a university to support graduates as they transition to new school leadership roles. First year research results of the Program for New Principals indicate that all of the program participants felt that the coaching program was a positive addition to the induction experience for new administrators. New principals viewed coaching positively and emphasized that it is both a valuable and unique form of professional development. Both coaches and new principals cited personalized support as one of the coaching model's most significant assets. The results should inform the development of a model of leadership coaching for new administrators. 相似文献
994.
Traditionally the kinetics of a chemical reaction has been studied as a set of coupled ordinary differential equations. The law of mass action, a tried and tested principle for reactions involving macroscopic quantities of reactants, gives rise to deterministic equations in which the variables are species concentrations. In recent years, though, as smaller and smaller systems – such as an individual biological cell, say – can be studied quantitatively, the importance of molecular discreteness in chemical reactions has increasingly been realized. This is particularly true when the system is far from the ‘thermodynamic limit’ when the numbers of all reacting molecular species involved are several orders of magnitude smaller than Avogadro’s number. In such situations, each reaction has to be treated as a probabilistic ‘event’ that occurs by chance when the appropriate reactants collide. Explicitly accounting for such processes has led to the development of sophisticated statistical methods for simulation of chemical reactions, particularly those occurring at the cellular and sub-cellular level. In this article, we describe this approach, the so-called stochastic simulation algorithm, and discuss applications to study the dynamics of model regulatory networks. 相似文献
995.
J. Fredericks Volkwein Lisa R. Lattuca Betty J. Harper Robert J. Domingo 《Research in higher education》2007,48(2):251-282
This research uses a conceptual model to examine the influence of a change in accreditation standards on a representative
national sample of 203 engineering programs at 40 institutions. Based on data collected from more than 140 program chairs,
1,200 faculty, 4,300 graduates of 2004, and 5,400 graduates of 1994, the study investigates the differential impact of the
change in accreditation standards on programs reviewed in different years during the period of transition. Despite significant
variation across most of the measures and groups in 1994 (before the introduction of the new accreditation criteria), the
2004 evidence demonstrates a surprisingly uniform level of student experiences and outcomes. These findings suggest that engineering
accreditation is beginning to accomplish its quality assurance goals.
This is a revised version of a research paper presented at the meeting of the Association for Institutional Research, May
17, 2006, Chicago, IL. 相似文献
996.
Metacognition and self-regulation are important for developing effective learning in the classroom and beyond, but novice learners often lack effective metacognitive and self-regulatory skills. However, researchers have demonstrated that metacognitive processes can be developed through practice and appropriate scaffolding. Betty’s Brain, an open-ended computer-based learning environment, helps students practice their cognitive skills and develop related metacognitive strategies as they learn science topics. In this paper, we analyze students’ activity sequences in a study that compared different categories of adaptive scaffolding in Betty’s Brain. The analysis techniques for measuring students’ cognitive and metacognitive processes extend our previous work on using sequence mining methods to discover students’ frequently-used behavior patterns by (i) developing a systematic approach for interpreting derived behavior patterns using a cognitive/metacognitive task model and (ii) analyzing the evolution of students’ frequent behavior patterns over time. Our results show that it is possible to identify students’ learning behaviors and analyze their evolution as they work in the Betty’s Brain environment. Further, the results illustrate that changes in student behavior were generally consistent with the scaffolding provided, suggesting that these metacognitive strategies can be taught to middle school students in computer-based learning environments. 相似文献
997.
Giles LV Warburton DE Esch BT Fedoruk MN Rupert JL Taunton JE 《Journal of sports sciences》2012,30(3):261-267
The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males. 相似文献
998.
Barr-Anderson DJ Neumark-Sztainer D Schmitz KH Ward DS Conway TL Pratt C Baggett CD Lytle L Pate RR 《Research quarterly for exercise and sport》2008,79(1):18-27
The current study examined associations between physical education (PE) class enjoyment and sociodemographic, personal, and perceived school environment factors among early adolescent girls. Participants included 1,511 sixth-grade girls who completed baseline assessments for the Trial of Activity in Adolescent Girls, with 50% indicating they enjoyed PE class a lot. Variables positively associated with PE class enjoyment included physical activity level, perceived benefits of physical activity, self-efficacy for leisure time physical activity, and perceived school climate for girls' physical activity as influenced by teachers, while body mass index was inversely associated with PE class enjoyment. After adjusting for all variables in the model, PE class enjoyment was significantly greater in Blacks than in Whites. In model testing, with mutual adjustment for all variables, self-efficacy was the strongest correlate of PE class enjoyment, followed by perceived benefits, race/ethnicity, and teachers' support for girls' physical activity, as compared to boys, at school. The overall model explained 11% of the variance in PE class enjoyment. Findings suggest that efforts to enhance girls' self-efficacy and perceived benefits and to provide a supportive PE class environment that promotes gender equality can potentially increase PE class enjoyment among young girls. 相似文献
999.
Mohamed Saifeddin Fessi Nidhal Zarrouk Valter Di Salvo Cristoforo Filetti Alan R. Barker 《Journal of sports sciences》2016,34(24):2189-2194
ABSTRACTThis study aimed to examine: (i) the effect of decreasing training load (TL) during taper weeks on physical match activities in professional soccer players, and (ii) to disclose the relationship between weekly TL and physical match activities. Rating of perceived exertion was collected after each training session and match to quantify the TL in 19 professional players over 17 standard and 7 taper weeks during the season. Physical match activities were quantified by a computerised match analysis system and compared between standard training and taper weeks. Compared to standard weeks, the duration and frequency of training sessions during the taper weeks decreased (?21.7% and ?18.8%, respectively; P < 0.01) with no change in intensity (?4.8%; P = 0.09). Consequently, the weekly TL decreased during the taper weeks (?25.5%; P < 0.01). Increases in distance covered by intense running (+15.1%; P < 0.05), high-intensity running (HIR) (+15.7%; P < 0.01), number of sprints (+17.8%; P < 0.05) and number of high-speed runs (+15.7%; P < 0.05) were observed during the seven matches played after the taper weeks. High relationships were observed between TL and HIR distance covered, number of HIR and number of sprints (r = ?0.53; r = ?0.55; r = ?0.65, respectively; P < 0.01). Decreasing TL during taper weeks by reducing training duration and frequency but maintaining intensity was associated with an increase in physical activities during matches. However, it needs to be determined whether tapering or other match factors led to the changes in match activity. 相似文献
1000.