提高高校羽毛球教学训练水平的探讨

根据我国羽毛球技战术特点,以及高等院校在我国羽毛球运动发展中应发挥的作用,采用理论与实践紧密结合的研究方法,提出了高等院校提高羽毛球教学训练水平应注意的问题;尤其是年青教师或教练员要加强学习,及时了解羽坛发展动态,掌握行之有效的教学手段与方法。     

The Reliability of Distance Run Tests for Children in Grades K—4

Abstract

The purpose of this study was to determine test–retest reliability for the 1-mile, 3/4-mile, and 1/2-mile distance run/walk tests for children in Grades K—4. Fifty-one intact physical education classes were randomly assigned to one of the three distance run conditions. A total of 1,229 (621 boys, 608 girls) complied the test–retests in the fall (October), with 1,050 of these students (543 boys, 507 girls) repeating the tests in the spring (May). Results indicated that the 1-mile run/walk distance, as recommended for young children in most national test batteries, has acceptable intraclass reliability (.83 < R < .90) for both boys and girls in Grades 3 and 4, has minimal (fall) to acceptable (spring) reliability for Grade 2 students (.70 < R < .83), but is not reliable for children in Grades K and 1 (.34 < R < .56). The 1/2 mile was the only distance meeting minimal reliability standards for boys and girls in Grades K and 1 (.73 < R < .82). Results also indicated that reliability estimates remained fairly stable across gender and age groups from the fall to spring testing periods, with the exception of the noticeably improved values for Grade 2 students on the 1-mile run/walk test. Criterion-referenced reliability (P, percent agreement) was also estimated relative to Physical Best and Fitnessgram run/walk standards. Reliability coefficients for all age group standards were acceptable to high (.70 < P < .95), except for Fitnessgram standards for 5-year-old girls on the 1-mile test for both fall and spring and for 6-year-old boys and girls on the 1-mile test administered in the spring.     

Effects of coffee and caffeine anhydrous on strength and sprint performance

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.     

Design-Based Research Within the Constraints of Practice: AlgebraByExample

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.     

Childhood Physical Fitness and Performance as Predictors of High School Sport Participation

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.     

Extending research on the interspersal procedure to perceptions of continuous reading assignments: Applied and theoretical implications of a failure to replicate

Researchers have shown that students' perceptions of mathematics assignments could be improved by interspersing additional briefer, easier problems (e.g., Logan and Skinner, 1998). The current study was designed to extend this research to reading tasks. Seventh‐grade students read out loud both a control passage and a similar experimental passage that contained additional interspersed brief (i.e., 16 words), easy (i.e., first‐grade reading level) paragraphs. Students then selected the passage that would require the least effort to read and the least time to read. Students also indicated the passage they liked most (preference) and the passage that they would like to read again (choice). Significantly more students selected the control passage as requiring less time to read, but no differences were found for preference, choice, or effort selections. The results failed to confirm earlier research on the interspersal procedure, thus our findings have applied and theoretical implications regarding causal variables that may account for the effectiveness of the interspersal procedure. Specifically, the current study suggests that the interspersal procedure may improve assignment perception only when the procedure increases discrete task‐completion rates. © 2001 John Wiley & Sons, Inc.     

DNA-Computing – ein funktionales Modell im laborpraktischen Experiment

Zusammenfassung.   Im Zentrum der Betrachtungen zum DNA-Computing steht die Frage nach den Chancen und Grenzen dieses neuen Berechnungsmodells, nachdem in den letzten Jahren eine rasante Entwicklung auf das Thema aufmerksam machte. Neben beachtlichen theoretischen Untersuchungen zum “Rechnen im Reagenzglas” werden auch laborpraktische Implementierungen favorisiert. An der TU Dresden wurde in interdisziplin?rer Arbeit ein Integer-Rucksackproblem mittels eines DNA-Algorithmus im Labor gel?st und dabei eine Vielzahl molekularbiologischer Operationen analysiert. Mit Hilfe dieses Satzes von Operationen gelang eine universelle und labornahe Modellierung des DNA-Computing. Hierbei angewandte Techniken und Methoden werden vorgestellt und bewertet. Die Beschreibung des DNA-Algorithmus zeigt, wie sich Einzeloperationen vorteilhaft zu Operationsfolgen zusammensetzen lassen und gemeinsam mit einer geeigneten DNA-Kodierung der Eingangsdaten zur L?sung des Problems im Labor führen. Erstmalig wurden hierbei natürliche Zahlen verarbeitet. Die Arbeitsgemeinschaft DNA-Computing Dresden konzentriert sich auf Aufgabenstellungen, die formale Modelle des DNA-Computing mit überzeugenden Laborimplementierungen verbinden. Eingegangen am 14. Februar 2000 / Angenommen am 26. Oktober 2000     

Reading comprehension of immigrant students in Germany: research evidence on determinants and target points for intervention

International studies, such as the Programme for International Student Assessment (PISA), have shown that, in most participating countries, students who do not typically speak the test language at home reach lower levels of reading comprehension than students using the test language at home (Stanat & Christensen, 2006). Results from PISA indicate that Germany is among the countries with the most pronounced differences in reading comprehension between immigrant students and students from native families. The present article summarizes these findings and shows that the reading achievement gap persists even when the socioeconomic and educational background of students?? families are controlled. Furthermore, although controlling for background factors reduces the effect of the language spoken at home on reading, it continues to be substantial. Using these findings as a starting point, the article addresses the question of what should be done to close this gap. It summarizes research findings indicating that oral proficiency presents an important determinant of reading comprehension in a second language. This suggests that effective general approaches to second-language teaching are needed to promote reading literacy in a L2. The article closes with a discussion of the available evidence on the effectiveness of such approaches and outlines the need for further research.     

Poverty,family resources and children's early educational attainment: The mediating role of parenting

This study uses longitudinal data from the UK Millennium Cohort Study to show the extent to which episodic and more persistent poverty in early childhood and the lack of other family resources disadvantage children at the start of their school careers in terms of whether they have achieved the target indicator of ‘good level of achievement’ on the Foundation Stage Profile. Positive parenting is shown to be an important contributor to school achievement that matters for children, regardless of poverty experience or family disadvantage. It is also shown to be an important mediator in redressing the effects of poverty and disadvantage.