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101.
Abstract

The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 ± 122 and 668 ± 37 W) was lower (P < 0.01) than either the highest (1074 ± 111 and 754 ± 56 W respectively) or the mean (1007 ± 125 and 701 ± 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 ± 30 W in males and 33 ± 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.  相似文献   
102.
Abstract

The purpose of this study was to determine the effects of a Nautilus circuit weight training program on muscular strength and maximal oxygen uptake ([Vdot]O 2 max) by comparing these effects to those produced by adhering to either a free weight (FW) strength training program or a running (R) program. Male college students who voluntarily enrolled in either a FW training class (n = 11), a Nautilus (N) circuit weight training class (n= 12), or a R conditioning class (n= 13) were subjects for this investigation. All groups participated in their respective programs 3 days per week for 10 weeks. Strength was assessed using a Cybex II isokinetic dynamometer set at an angular velocity of 60° · s ?1 and a damping of 2. The FW group served as the control group for the assessment of [Vdot]O 2 max changes, while the R group served as controls for the assessment of strength differences. ANCOVA revealed that the N and R groups experienced significant (p < .01) increases in [Vdot]O 2 max expressed in L · min ?1 (10.9 and 11.4%), ml · kg ?1 · min ?1 (10.8 and 11.7%), and ml · kgLBW ?1 · min ?1 (7.1 and 7.5%) when compared to the FW group. There were no significant differences between the N and R groups. There were no significant differences among groups in final peak torque values (after covariance), and torque at the beginning and end of the range of motion for the knee extensors, knee flexors, elbow extensors, and elbow flexors. In general, isokinetic strength values elicited by the N group compared favorably to those generated by the FW group. It was concluded that for a training period of short duration, Nautilus circuit weight training appears to be an equally effective alternative to standard free weight (strength) and aerobic (endurance) training programs for untrained individuals.  相似文献   
103.
Persistent fear of crime can have serious consequences for one’s social behavior. Previous research has shown that people who fear crime are more likely to engage in self-protective behavior. Although a substantial amount of research has examined the relationship between television exposure and fear of crime, research on the association between television exposure and self-protective behavior is scarce. Based on cultivation theory and the mediated fear model, the current study aimed to examine whether news and crime drama television viewing are indirectly related to self-protective behavior via fear of crime. Structural equation modeling of data from 392 undergraduate students showed that news viewing and crime drama viewing is indirectly associated with self-protective behavior. The current study provided evidence for the importance of accounting for gender when investigating the complex issue of media effects on fear of crime and self-protective behavior.  相似文献   
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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.  相似文献   
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109.
Chat reference refers to the use of instant messaging and call center software to support interactive text or voice communication with library patrons. Instant messaging has been integrated into many e-commerce environments, and into the social lives of many teenagers and young adults, affording a level of immediacy and intimacy not possible with e-mail applications. The convergence and interoperability of new and emerging technologies can be used to develop new communities of users that view libraries as being essential to their education, patient care, and research activities.  相似文献   
110.
In response to curricular changes, many academic health sciences librarians have participated in curriculum planning and/or developed informatics course requirements for students enrolled at health sciences universities. This article describes the use of clinical vignette assignments, student journal club activities, and vignette-type multiple choice questions to teach and assess skills related to managing biomedical information, communicating effectively, basic computing, and life-long learning.  相似文献   
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