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21.
The current research examined whether instructional activities centering on contrasting cases promoted secondary school students’ evaluations of source features present in a multiple-documents inquiry context. Two hypothetical students’ document evaluation strategy protocols were designed: One featured more sophisticated strategies commonly enacted by experts and better college students and a second featured less sophisticated strategies commonly enacted by secondary school students. A series of classroom-based activities required that students compare/contrast the two protocols to decide which were the best strategies when analyzing multiple scientific documents and why. The findings demonstrated that students who previously participated in the intervention activities included more scientific concepts from more useful documents when generating essay responses from memory, displayed better rankings of the usefulness of the set of multiple documents, and offered more principled justifications based on source feature evaluations of trustworthiness compared to students who instead received typical classroom instruction. We discuss the instructional implications of a contrasting-cases approach in facilitating secondary school students’ usage of source features within multiple-documents inquiry contexts.  相似文献   
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This investigation provides an extensive review of scientific, religious, and otherwise non-scientific factors that may influence student acceptance of biological evolution. We also measure the extent to which students' levels of acceptance changed following an educational experience designed to address an inclusive inventory of factors identified as potentially affecting student acceptance of evolution (n = 81, pre-test/post-test) n = 37, one-year longitudinal). Acceptance of evolution was measured using the Measure of Acceptance of the Theory of Evolution (MATE) instrument among participants enrolled in a secondary-level academic programme during the summer prior to their final year of high school and as they transitioned to the post-secondary level. Student acceptance of evolution was measured to be significantly higher than initial levels both immediately following and over one year after the educational experience. Results reported herein carry implications for future quantitative and qualitative research as well as for cross-disciplinary instruction plans related to evolutionary science and non-scientific factors which may influence student understanding of evolution.  相似文献   
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Abstract

Nine males cycled at 53% (s = 2) of their peak oxygen uptake ([Vdot]O2peak) for 90 min (dry bulb temperature: 25.4°C, s = 0.2; relative humidity: 61%, s = 3). One litre of flavoured water at 10 (cold), 37 (warm) or 50°C (hot) was ingested 30 – 40 min into exercise. Immediately after the 90 min of exercise, participants cycled at 95%[Vdot]O2peak to exhaustion to assess exercise capacity. Rectal and mean skin temperatures and heart rate were recorded. The gradient of rise in rectal temperature was influenced (P < 0.01) by drink temperature. Mean skin temperature was highest in the hot trial (cold trial: 34.2°C, s = 0.5; warm trial: 34.4°C, s = 0.5; hot trial: 34.7°C, s = 0.6; P < 0.01). Significant differences were observed in heart rate (cold trial: 132 beats · min?1, s = 13; warm trial: 134 beats · min?1, s = 12; hot trial: 139 beats · min?1, s = 13; P < 0.05). Exercise capacity was similar between trials (cold trial: 234 s, s = 69; warm trial: 214 s, s = 52; hot trial: 203 s, s = 53; P = 0.562). The heat load and debt induced via drinking resulted in appropriate thermoregulatory reflexes during exercise leading to an observed heat content difference of only 33 kJ instead of the predicted 167 kJ between the cold and hot trials. These results suggest that there may be a role for drink temperature in influencing thermoregulation during exercise.  相似文献   
24.
An improvement on the transient response of tracking for the sampled-data system based on an improved PD-type iterative learning control (ILC) is proposed in this paper. The developed analog ILC method and the high-gain property tracker design methodology are first combined to significantly reduce learning epochs and overcome the initial condition shift problem and discontinuous reference input in the traditional ILC. Besides, the proposed ILC improves the transient response and decreases the rate of weighting matrices QQ to RR under the traditional linear quadratic tracker design. First, the off-line observer/Kalman filter identification (OKID) is used to determine the appropriate (low-) order system parameters and state estimator for the physical system with unknown system equation, so that the model-based PD-type ILC can be implemented for practical applications. Then, to improve the transient response and decrease the control effort, the proportional difference type (PD-type) ILC algorithm is combined with the high-gain property linear quadratic tracker (LQT) design to construct the high performance tracker for the model-based sampled-data systems. Furthermore, the discrete-time version high performance tracker design for the unknown stochastic sampled-data system via the iterative learning control method is proposed in this paper based on the Euler method and the digital redesign approach. Finally, some examples are given for illustrating the effectiveness of the proposed method.  相似文献   
25.
We extend debates about the sources of university capabilities at research commercialization. Drawing upon quantitative data for a panel of 89 research-intensive US universities and interview data from two academic licensing offices, we model the relationship between technology transfer experience, embeddedness in biotechnology industry networks, basic science quality and capacity, and citation impact measures of university life science patents. Technology licensing officers draw upon the expertise of corporate partners to evaluate the potential impact of invention disclosures. The information gleaned through network ties to industry enables well-connected institutions to develop higher impact patent portfolios. Reaping the benefits of such connections, however, requires experience in balancing academic and corporate priorities to avoid the danger of ‘capture’ by industrial interests as overly tight connections limit patent impact. This pattern of diminishing returns to connectivity is robust across multiple citation measures of patent quality.  相似文献   
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This study describes the status of small school reforms in U.S. high schools and contemplates their future. It asks how cultural and instructional reforms differ across school reform types. Analyses focus on indicators of teacher and student culture as well as instructional reforms including project-based learning (PBL) and other inquiry-related practices. Findings are based on data from a national survey completed by 395 high school teachers who were responsible for and had used PBL in core academic subjects. Study participants taught in large, comprehensive high schools; in schools that had converted to small learning communities; and in newly created small school start-ups. Some of these small schools and conversions were based on a reform model, and others were not. Teachers in reform model schools reported the greatest number of cultural and instructional reforms, followed by teachers in other small schools. Reform models were particularly strong on instructional reforms and student culture. In general, start-up teachers reported more success implementing reforms than teachers in conversion schools, and teacher culture was reformed much more often than student culture and instruction. These findings help shed light on how widely practices and conditions have spread throughout the broader small schools movement, and which of these (including extensive PBL use) only seem to flourish in schools that subscribe to a holistic reform model.  相似文献   
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29.
Braiding is not currently used in the production of golf shafts. The objective of this work was to develop, through a modelling process consisting of altering lamina sequence, a golf shaft, using braided laminas, which would have mass, stiffness and torque comparable to commercially available composite and steel shafts. A 2D conical braided composite model was previously developed and validated to predict elastic constants of braided closed meshed structures. Energy methods were used to calculate the stiffness and torque of shafts using prescribed industry approaches. Shaft mass was calculated based on geometry and density of constitutent materials. Modelled shafts had both braided and unidirectional layers and compared favourably with or were better than commercially available composite and steel shafts in terms of deflection force and twist angle; they had the same weight as composite shafts but were much lighter than steel shafts. If these findings are verified, braided composites would be a viable and effective approach to the design of future golf shafts.  相似文献   
30.
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