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991.
Eric T. Trexler Erica J. Roelofs Katie R. Hirsch Meredith G. Mock 《European Journal of Sport Science》2016,16(6):702-710
Caffeine and coffee are widely used among active individuals to enhance performance. The purpose of the current study was to compare the effects of acute coffee (COF) and caffeine anhydrous (CAF) intake on strength and sprint performance. Fifty-four resistance-trained males completed strength testing, consisting of one-rep max (1RM) and repetitions to fatigue (RTF) at 80% of 1RM for leg press (LP) and bench press (BP). Participants then completed five, 10-second cycle ergometer sprints separated by one minute of rest. Peak power (PP) and total work (TW) were recorded for each sprint. At least 48 hours later, participants returned and ingested a beverage containing CAF (300?mg flat dose; yielding 3–5?mg/kg bodyweight), COF (8.9?g; 303?mg caffeine), or placebo (PLA; 3.8?g non-caloric flavouring) 30 minutes before testing. LP 1RM was improved more by COF than CAF (p?=?.04), but not PLA (p?=?.99). Significant interactions were not observed for BP 1RM, BP RTF, or LP RTF (p?>?.05). There were no sprint?×?treatment interactions for PP or TW (p?>?.05). 95% confidence intervals revealed a significant improvement in sprint 1 TW for CAF, but not COF or PLA. For PLA, significant reductions were observed in sprint 4 PP, sprint 2 TW, sprint 4 TW, and average TW; significant reductions were not observed with CAF or COF. Neither COF nor CAF improved strength outcomes more than PLA, while both groups attenuated sprint power reductions to a similar degree. Coffee and caffeine anhydrous may be considered suitable pre-exercise caffeine sources for high-intensity exercise. 相似文献
992.
Reis R 《Science communication》1999,21(2):137-155
This article examines how two important Brazilian newspapers (Floha de S. Paulo and O Globo) covered the UN Conference on Environment and Development (UNCED) or Earth Summit. The analysis will also determine the characteristics of the environmental media and its significance when it comes to coverage of environmental issues. This article provides historical background information on the environmental media in the US and in Brazil, contextual information on the Earth Summit, a content analysis of stories about UNCED published by the two Brazilian newspapers. Overall, 649 news items were used to determine the type of sources used, as well as the kind of issues covered. The analysis showed that government officials were the most frequently cited sources, while environmentalists and scientists were all but ignored as news sources. The analysis also indicated that economic issues were surprisingly prominent in the coverage. These results are compatible with the previous studies done in several countries and indicate that environmental media are still extremely reliant on "official" voices. The finding also highlight the fact that the range of issues covered by the environmental media largely reflects the perceived public agenda. 相似文献
993.
SummaryThe rate at which chloride ions diffuse from archaeological iron into a treatment solution depends on how the chloride ions are initially distributed in the corrosion layer. This paper compares solutions of the diffusion equation for two limiting cases: (1) where the chloride ions are initially spread uniformly through the corrosion layer; and (2) where the chloride ions are initially concentrated at the interface between the iron and the corrosion layer. Although the first model has been used in the past to describe chloride ions diffusing from marine iron, the second is more appropriate in cases where corrosion has drawn chloride ions toward the iron surface. Because diffusion processes in archaeological iron are complicated, the limitations of both these models are discussed. 相似文献
994.
Julie L. Booth Laura A. Cooper Alexandra Huyghe Kenneth R. Koedinger E. Juliana Paré-Blagoev 《Journal of Education for Students Placed at Risk》2015,20(1-2):79-100
Superintendents from districts in the Minority Student Achievement Network (MSAN) challenged the Strategic Education Research Partnership (SERP) to identify an approach to narrowing the minority student achievement gap in Algebra 1 without isolating minority students for intervention. SERP partnered with 8 MSAN districts and researchers from 3 universities to design and rigorously test AlgebraByExample, a set of 42 Algebra 1 assignments with interleaved worked examples that target common misconceptions and errors. In a year-long random-assignment study, students who received AlgebraByExample assignments had an average 7 percentage point boost on a posttest containing released items from state assessments, and students in the bottom half of the performance distribution where minority students are disproportionately concentrated had an average 10 percentage point boost on a researcher-designed assessment of conceptual understanding. AlgebraByExample is easily incorporated into any existing curriculum, and naturally serves as a launch point for mathematically rich discussion. 相似文献
995.
The purpose of this article is to introduce a research design, which aims to find useful pedagogical adaptations for teaching pupils with autism. Autism is a behavioural syndrome characterised by disabilities and dysfunctions in interaction and communication, which is why it is interesting to explore educational processes particularly from an interactional perspective in a class with pupils with autism. The main focus is in exploring teacher’s tacit knowledge and interactional co-regulation between the teacher and the pupils. This study is a part of a larger Finnish project, which involves the education of pupils with autism in the primary school system. In the study described, six video recordings (each about 30?min) were taken under analysis due to the uniqueness in the research context of special education: the videos are rare in that they involve only the teacher and her six pupils with autism; no helpers are present in the classroom. This study explored the phenomenon ethnomethodologically. This study indicated that it is possible to apply a general theory of interaction when exploring people with autism, although the main diagnostic criteria of autism are disabilities in social interaction and communication. It was possible to extract episodes from the behaviour of the teacher that showed her tacit knowledge becoming concrete. These results could be taken into consideration when planning and carrying out teaching in different contexts and in teacher education, too. 相似文献
996.
Erika L. Hunt 《Community College Journal of Research & Practice》2013,37(11):863-881
While the strategy of funding both systems provides an incentive for both school districts and community colleges to participate with dual enrollment, the current fiscal environment has drawn attention to the inefficient use of the dual funding structure. This article highlights the results of a case study on Florida's dual enrollment program documenting how over a 20-year period policymakers offered different financial incentives as an inducement to greater participation among districts and community colleges. The article documents how the current state fiscal condition has altered lawmaker's motivations for supporting dual enrollment. It concludes by describing the implications of this on community college participation with dual enrollment. 相似文献
997.
Rebecca A. Battista Erin D Bouldin Karin A. Pfeiffer Christine E. Pacewicz Shannon R Siegel Eric M. Martin 《Measurement in physical education and exercise science》2021,25(1):43-52
ABSTRACT Participation in youth sport is positively associated with physical fitness and performance. The purpose of the current study was to examine if physical fitness measures during childhood and early adolescence predicted high school sport participation. Participants included youth in the Michigan State University Motor Performance Study. Measures consisted of the endurance shuttle run, Wells sit-and-reach, jump and reach, standing long jump, agility shuttle run and 30-yard dash. Individual, generalized estimating equation models were used to estimate the association between each measure and the odds of participating in high school sport. For both sexes, the endurance shuttle run and agility shuttle run were related to sport participation. For boys only, the long jump and 30-yard dash were also associated with sport participation. Better physical fitness and performance across several dimensions in childhood, including those related to motor skills, enhanced the likelihood of sport participation in high school. 相似文献
998.
Children's spelling development is often described by researchers and educators as proceeding through a series of stages. Two properties of stages were analyzed in this study. If spelling development can be characterized by stages, then it should be possible to observe qualitatively different spellings at different points in development. In addition, spellings within a point of development must be consistent. Spelling samples were obtained from stories written by children in first through sixth grade. Stage classifications of spellings for (a) silent -e long vowel words (e.g., bake), and (b) regularly affixed past tense words phonologically represented as /t/ (e.g., helped), /d/ (e.g., opened), and /ed/ (e.g., listed) were analyzed. Little evidence was found for either predicted qualitative differences in stage classification of errors or in stage constancy across grades. Implications for theories of spelling development and instructional practice are discussed. 相似文献
999.
The need for science communication programs is matched with the need for program evaluation. This case study is an evaluation of the “Decoding Science” program (DSP) [Rodgers et al. (2018). Science Communication, 40(1), 3–32], a science communication training program, and examines key experiential-learning themes [Kolb, D. A. (1984). Experiential learning: Experience as the source of learning and development. Englewood Cliffs, NJ: Prentice-Hall]. Specifically, we discuss the program's emphasis on learning that science communication is a process that (a) is continual, (b) involves conflict resolution, (c) requires adaptation to the world, (d) requires environmental interaction, and leads to (e) knowledge creation. Additionally, we discuss our analysis of student feedback. Results suggest that the DSP successfully utilizes experiential learning to facilitate the learning of science communication techniques and that future evaluations can lead to the development and improvement of science communication training programs. 相似文献
1000.