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111.
Instructional practices in secondary science: How teachers achieve local and standards-based success
Beth A. Covitt Elizabeth Xeng de los Santos Qinyun Lin Christie Morrison Thomas Charles W. Anderson 《科学教学研究杂志》2024,61(1):170-202
This article reports on analyses of the instructional practices of six middle- and high-school science teachers in the United States who participated in a research-practice partnership that aims to support reform science education goals at scale. All six teachers were well qualified, experienced, and locally successful—respected by students, parents, colleagues, and administrators—but they differed in their success in supporting students' three-dimensional learning. Our goal is to understand how the teachers' instructional practices contributed to their similarities in achieving local success and to differences in enabling students' learning, and to consider the implications of these findings for research-practice partnerships. Data sources included classroom videos supplemented by interviews with teachers and focus students and examples of student work. We also compared students' learning gains by teacher using pre–post assessments that elicited three-dimensional performances. Analyses of classroom videos showed how all six teachers achieved local success—they led effectively managed classrooms, covered the curriculum by teaching almost all unit activities, and assessed students' work in fair and efficient ways. There were important differences, however, in how teachers engaged students in science practices. Teachers in classrooms where students achieved lower learning gains followed a pattern of practice we describe as activity-based teaching, in which students completed investigations and hands-on activities with few opportunities for sensemaking discussions or three-dimensional science performances. Teachers whose students achieved higher learning gains combined the social stability characteristic of local classroom success with more demanding instructional practices associated with scientific sensemaking and cognitive apprenticeship. We conclude with a discussion of implications for research-practice partnerships, highlighting how partnerships need to support all teachers in achieving both local and standards-based success. 相似文献
112.
Corey W. Joseph Elizabeth J. Bradshaw Justin Kemp Ross A. Clark 《Sports biomechanics / International Society of Biomechanics in Sports》2014,13(3):241-258
Eccentric contractions that provide spring energy can also cause muscle damage. The aim of this study was to explore leg and vertical stiffness following muscle damage induced by an eccentric exercise protocol. Twenty active males completed 60 minutes of backward-walking on a treadmill at 0.67 m/s and a gradient of ? 8.5° to induce muscle damage. Tests were performed immediately before; immediately post; and 24, 48, and 168 hours post eccentric exercise. Tests included running at 3.35 m/s and hopping at 2.2 Hz using single- and double-legged actions. Leg and vertical stiffness were measured from kinetic and kinematic data, and electromyography (EMG) of five muscles of the preferred limb were recorded during hopping. Increases in pain scores (over 37%) occurred post-exercise and 24 and 48 hours later (p < 0.001). A 7% decrease in maximal voluntary contraction occurred immediately post-exercise (p = 0.019). Changes in knee kinematics during single-legged hopping were observed 168 hours post (p < 0.05). No significant changes were observed in EMG, creatine kinase activity, leg, or vertical stiffness. Results indicate that knee mechanics may be altered to maintain consistent levels of leg and vertical stiffness when eccentric exercise-induced muscle damage is present in the lower legs. 相似文献
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Elizabeth Connor Book Review Editor 《Medical reference services quarterly》2013,32(4):473-485
No abstract available for this article. 相似文献
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Stephen P Bailey Laureen Brown Elizabeth K Bailey 《Cardiopulmonary Physical Therapy Journal》2008,19(1):3-10
Individuals with chronic obstructive pulmonary disease (COPD) have been shown to benefit from participation in pulmonary rehabilitation (PR) programs that include exercise training and education. Purpose: To examine the relationship between improvements in 6 minute walk distance and perceived quality of life in individuals with COPD following completion of a PR program. Methods: The records of 139 individuals completing a PR program (3 times a week for 8 weeks) were retrospectively examined. Prior to entry and upon completion of the program each individual completed a 6 minute walk test (6MWT), the SF-36 Health survey, and the UCSD Shortness of Breath Questionnaire (SOB). SF-36 results were analyzed according to 8 subscales [Physical Functioning (PF), Role Physical (RF), Bodily Pain (BP), General Health (GH), Vitality (V), Social Functioning (SF), Role Emotional (RE), and Mental Health (MH)]. Results: PR resulted in significant improvements in 6MWTdistance (Pre = 845 ± 37 ft, Post = 1127 ± 32 ft, p < 0.001), PF (p < 0.001), RF (p = 0.001), Vitality (p = 0.002), SF (p < 0.001), RE (p = 0.037), MH (p < 0.001) and SOB (Pre = 53 ± 2, Post = 47 ± 2, p < 0.001). The change in 6MWT distance was not related to changes in PF (r = 0.17), RF (r = 0.03), GH (r = 0.03), Vitality (r = −0.001), SF (r = 0.01), RE (r = 0.06), MH (r = −0.04) or SOB (r = 0.12). The magnitude of improvement in 6MWT distance (68%) was much greater than that observed in PF (15%), RF (16%), GH (6%), VT (18%), SF (20%), RE (14%), MH (14%), or SOB (8%). Conclusions: PR has a positive impact on 6 minute walk distance and perceived quality of life in individuals with COPD; however, changes in 6 minute walk distance appear to have no relationship to changes in perceived quality of life. 相似文献
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Details of the preparation and the immunogenic properties of an ultraviolet-inactivated poliomyelitis vaccine are described. The data presented indicate that the SK murine strain of the virus may be inactivated by controlled irradiation and yet retain sufficient immunizing potency to protect mice against 1,000 to 10,000 M.L.D. of the active virus administered intraperitoneally or intranasally. 相似文献
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