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51.
Individuals with chronic obstructive pulmonary disease (COPD) have been shown to benefit from participation in pulmonary rehabilitation (PR) programs that include exercise training and education. Purpose: To examine the relationship between improvements in 6 minute walk distance and perceived quality of life in individuals with COPD following completion of a PR program. Methods: The records of 139 individuals completing a PR program (3 times a week for 8 weeks) were retrospectively examined. Prior to entry and upon completion of the program each individual completed a 6 minute walk test (6MWT), the SF-36 Health survey, and the UCSD Shortness of Breath Questionnaire (SOB). SF-36 results were analyzed according to 8 subscales [Physical Functioning (PF), Role Physical (RF), Bodily Pain (BP), General Health (GH), Vitality (V), Social Functioning (SF), Role Emotional (RE), and Mental Health (MH)]. Results: PR resulted in significant improvements in 6MWTdistance (Pre = 845 ± 37 ft, Post = 1127 ± 32 ft, p < 0.001), PF (p < 0.001), RF (p = 0.001), Vitality (p = 0.002), SF (p < 0.001), RE (p = 0.037), MH (p < 0.001) and SOB (Pre = 53 ± 2, Post = 47 ± 2, p < 0.001). The change in 6MWT distance was not related to changes in PF (r = 0.17), RF (r = 0.03), GH (r = 0.03), Vitality (r = −0.001), SF (r = 0.01), RE (r = 0.06), MH (r = −0.04) or SOB (r = 0.12). The magnitude of improvement in 6MWT distance (68%) was much greater than that observed in PF (15%), RF (16%), GH (6%), VT (18%), SF (20%), RE (14%), MH (14%), or SOB (8%). Conclusions: PR has a positive impact on 6 minute walk distance and perceived quality of life in individuals with COPD; however, changes in 6 minute walk distance appear to have no relationship to changes in perceived quality of life.  相似文献   
52.
Because school violence is widespread, social and emotional competence must be targeted. Second Step is a social and emotional violence‐prevention curriculum that teaches prosocial skills and reduces aggressive behavior. The purpose of this study was to examine the effects of Second Step implementation on students (N = 403) in preschool through fourth grade who were predominately Latino, English language learners, and from families with low socioeconomic status. The data of 165 out of the 403 students were included in the present study. Analyses consisted of paired‐samples t‐tests to identify changes in social and emotional knowledge and behavioral and emotional risk. Results showed that there was a significant increase in both social and emotional knowledge and behavioral and emotional risk following the implementation of Second Step. These results are discussed with regard to previous and future research, limitations, and implications for school practice.  相似文献   
53.
Parents play a key role in developing their children's academic motivation, and parents of children with gifts and talents also may face additional parenting challenges that are less commonly faced by parents of average‐ability learners whose needs are more readily met in the school setting. School psychologists may be charged with addressing these issues, despite having little or no training on the needs of families of high‐ability learners. We use the lens provided by the self‐determination theory of motivation to consider how social–environmental climates created by parents can promote or impede the academic motivation of students with gifts and talents. © 2012 Wiley Periodicals, Inc.  相似文献   
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In recent years, colleges have been moving from traditional, classroom‐based student evaluations of instruction to online evaluations. Because of the importance of these evaluations in decisions regarding retention, promotion and tenure, instructors are justifiably concerned about how this trend might affect their ratings. We recruited faculty members who were teaching two or more sections of the same course in a single semester and assigned at least one section to receive online evaluations and the other section(s) to receive classroom evaluations. We hypothesised that the online evaluations would yield a lower response rate than the classroom administration. We also predicted that there would be no significant differences in the overall ratings, the number of written comments, and the valence (positive/neutral/negative) of students’ comments. A total of 32 instructors participated in the study over two semesters, providing evaluation data from 2057 students. As expected, online evaluations had a significantly lower response rate than classroom evaluations. Additionally, there were no differences in the mean ratings, the percentage of students who provided written comments or the proportion of comments in the three valence categories. Thus, even with the lower response rate for online evaluations, the two administration formats seemed to produce comparable data.  相似文献   
56.
This study examined how activity type influenced heart rates and time spent in target heart rate zones of high school students participating in physical education classes. Significantly higher average heart rates existed for fitness (142 +/- 24 beats per minute [bpm]) compared to team (118 +/- 24 bpm) or individual (114 +/- 18) activities. Similar results occurred for the percentage of activity time spent within a target heart rate zone (fitness 81.7 +/- 15.9%, individual 68.4 +/- 30.5%, and team 60.6 +/- 30.5%). Boys attained higher heart rates during team activities, while female students had higher rates during individual activities indicating male and female adolescents respond differently to activity types. The highest mean heart rates were observed during fitness activities.  相似文献   
57.
Purpose: An advanced system for the assessment of climbing-specific performance was developed and used to: (a) investigate the effect of arm fixation (AF) on construct validity evidence and reliability of climbing-specific finger-strength measurement; (b) assess reliability of finger-strength and endurance measurements; and (c) evaluate the relationship between finger flexor all-out test scores and climbing ability. Methods: To determine the effect of AF, 22 male climbers performed 2 maximal strength and all-out tests with AF (shoulder and elbow flexed at 90°) and without AF (shoulder flexed at 180° and elbow fully extended). To determine reliability, 9 male climbers completed 2 maximal strength tests with and without AF and an all-out and intermittent test without AF. Results: The maximal strength test without AF more strongly determined climbing ability than the test with AF (r2 = .48 and r2 = .42 for sport climbing; r2 = .66 and r2 = .42 for bouldering, respectively). Force and time variables were highly reliable; the rate of force development and fatigue index had moderate and low reliability. The maximal strength test with AF provided slightly higher reliability than without AF (intraclass correlation coefficient [ICC] = 0.94, ICC = 0.88, respectively). However, smaller maximal forces were achieved during AF (484 ± 112 N) than without AF (546 ± 132 N). All-out test average force had sufficiently high reliability (ICC = 0.92) and a relationship to sport climbing (r2 = .42) and bouldering ability (r2 = .58). Conclusion: Finger strength and endurance measurements provided sufficient construct validity evidence and high reliability for time and force parameters. Arm fixation provides more reliable results; however, the position without AF is recommended as it is more related to climbing ability.  相似文献   
58.
The purpose of this study was to explore the effects of the perceived purpose of exercising on the self-selected distance peddled during an acute cycling task. Participants were randomly assigned to one of three groups (health, wealth, charity). All participants watched a video emphasizing the health benefits of performing at least 30?min of daily exercise. Those in the health group were not provided any additional information. Those in the wealth group were then informed that they would earn money for every two kilometres cycled. Those in the charity group were informed that they would earn money for a charity for every two kilometres cycled. Participants were not given a time/distance limit and were instructed to cycle until they chose to stop. Analyses revealed that participants in the wealth and charity group cycled significantly farther than those in the health group (approximately twice as far). Additionally, a significant sex by group interaction showed that women cycled farther for charity while men cycled farther for wealth. These results suggest that health messages used to increase exercise behaviour may benefit from exploring how paradigms from behavioural economics influence behaviors that have relevance to public health.  相似文献   
59.
The Oregon State University Valley Library has been open 24 hours per day, five days per week, during regular academic terms since 2010. The authors collected survey data during 2012 to explore how students used the hours and whether they perceived that the provision of 24/5 hours contributes to their academic success. Nearly 90% of the respondents believed that their use of the overnight hours made a difference in their performance. The demographic, usage, and perception of value data collected provide a useful snapshot of overnight usage in this exploratory study.  相似文献   
60.
Bundling can be a pricing mechanism by which monopolists capture economic surplus from consumers.We suggest that given the cost structure of media markets, channel bundling in the cable and satellite market could also emerge in a competitive environment. A la carte channel pricing on cable television may or may not increase consumer welfare and could decrease total welfare. Because bundling may create other problems, policymakers may consider allowing cable and satellite networks to sell packages of channel space to viewers at a given price, allowing viewers to choose which channels they want in their packages. We term this option quasi-bundling.  相似文献   
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