Effect of gear ratio on peak power and time to peak power in BMX cyclists

The aim of this study was to ascertain if gear ratio selection would have an effect on peak power and time to peak power production in elite Bicycle Motocross (BMX) cyclists. Eight male elite BMX riders volunteered for the study. Each rider performed three, 10-s maximal sprints on an Olympic standard indoor BMX track. The riders’ bicycles were fitted with a portable SRM power meter. Each rider performed the three sprints using gear ratios of 41/16, 43/16 and 45/16 tooth. The results from the 41/16 and 45/16 gear ratios were compared to the current standard 43/16 gear ratio. Statistically, significant differences were found between the gear ratios for peak power (F(2,14)?=?6.448; p?=?.010) and peak torque (F(2,14)?=?4.777; p?=?.026), but no significant difference was found for time to peak power (F(2,14)?=?0.200; p?=?.821). When comparing gear ratios, the results showed a 45/16 gear ratio elicited the highest peak power,1658?±?221?W, compared to 1436?±?129?W and 1380?±?56?W, for the 43/16 and 41/16 ratios, respectively. The time to peak power showed a 41/16 tooth gear ratio attained peak power in ?0.01?s and a 45/16 in 0.22?s compared to the 43/16. The findings of this study suggest that gear ratio choice has a significant effect on peak power production, though time to peak power output is not significantly affected. Therefore, selecting a higher gear ratio results in riders attaining higher power outputs without reducing their start time.     

Evaluating the Comparability of Paper‐ and Computer‐Based Science Tests Across Sex and SES Subgroups

As access and reliance on technology continue to increase, so does the use of computerized testing for admissions, licensure/certification, and accountability exams. Nonetheless, full computer‐based test (CBT) implementation can be difficult due to limited resources. As a result, some testing programs offer both CBT and paper‐based test (PBT) administration formats. In such situations, evidence that scores obtained from different formats are comparable must be gathered. In this study, we illustrate how contemporary statistical methods can be used to provide evidence regarding the comparability of CBT and PBT scores at the total test score and item levels. Specifically, we looked at the invariance of test structure and item functioning across test administration mode across subgroups of students defined by SES and sex. Multiple replications of both confirmatory factor analysis and Rasch differential item functioning analyses were used to assess invariance at the factorial and item levels. Results revealed a unidimensional construct with moderate statistical support for strong factorial‐level invariance across SES subgroups, and moderate support of invariance across sex. Issues involved in applying these analyses to future evaluations of the comparability of scores from different versions of a test are discussed.     

Reflections on a post September 11 student‐led project: Teaching strategies that foster tolerance and emotional coping

Abstract

Sixteen preservice teachers participated in a service‐learning project to build tolerance in the community as a result of their desire to do something or to make a difference after the terrorist attacks of September 11, 2001. Student reflection papers revealed an increase in student tolerance and feelings of competence after participating in the project. Student‐led project work enabled students to direct their own learning, reflect on feelings about terrorism and tolerance, participate in collaborative relationships and make a contribution to campus and community life. Advocacy and mentoring are discussed as key teaching strategies for replicating project outcomes. © 2004 Published by Elsevier Inc.     

Looking for love in all the wrong places: Accessing sexual and reproductive health information via the Readers' Guide to Periodical Literature

The Readers' Guide to Periodical Literature has been described as a cultural barometer. It supports scholars of history and culture by providing access to ideas circulated via the mass media in earlier times, but its own coverage and indexing practices also reveal attitudes and values toward issues of the time. The Progressive Era (1900–1924) coincides with the founding and growth of the Readers' Guide. Examining how the Readers' Guide directed readers' attention to matters of sexual and reproductive health in its first quarter century demonstrates changes in social attitudes and has implications for scholarly work. The array of index terms required to locate information on this topic indicates both barriers to information access for contemporary readers as well as challenges for present-day scholars concerned with recovering information of the era.     

A study of color in dissertations and theses

This study examined the occurrence of color in dissertations and theses produced at the Pennsylvania State University over a nine year period. Since the most common preservation method for dissertations and theses is monochromatic microfilming, traditional treatment may result in a loss of information encoded in color in these resources. Results indicate a significant increase in the use of color over the time period studied. Variations in the amount of color use by discipline were also observed. Implications related to monochromatic microfilming and recommendations for long term preservation are discussed.