On microscopic vision and a new form of microscope     

D. Brewster 《Journal of The Franklin Institute》1860,70(4):249-251

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Clarifying coal oils     

F.A. Abel 《Journal of The Franklin Institute》1860,70(2):123-124

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Heart rates of high school physical education students during team sports, individual sports, and fitness activities     

Laurson KR  Brown DD  Cullen RW  Dennis KK 《Research quarterly for exercise and sport》2008,79(1):85-91

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   

But I like PE: factors associated with enjoyment of physical education class in middle school girls     

Barr-Anderson DJ  Neumark-Sztainer D  Schmitz KH  Ward DS  Conway TL  Pratt C  Baggett CD  Lytle L  Pate RR 《Research quarterly for exercise and sport》2008,79(1):18-27

The current study examined associations between physical education (PE) class enjoyment and sociodemographic, personal, and perceived school environment factors among early adolescent girls. Participants included 1,511 sixth-grade girls who completed baseline assessments for the Trial of Activity in Adolescent Girls, with 50% indicating they enjoyed PE class a lot. Variables positively associated with PE class enjoyment included physical activity level, perceived benefits of physical activity, self-efficacy for leisure time physical activity, and perceived school climate for girls' physical activity as influenced by teachers, while body mass index was inversely associated with PE class enjoyment. After adjusting for all variables in the model, PE class enjoyment was significantly greater in Blacks than in Whites. In model testing, with mutual adjustment for all variables, self-efficacy was the strongest correlate of PE class enjoyment, followed by perceived benefits, race/ethnicity, and teachers' support for girls' physical activity, as compared to boys, at school. The overall model explained 11% of the variance in PE class enjoyment. Findings suggest that efforts to enhance girls' self-efficacy and perceived benefits and to provide a supportive PE class environment that promotes gender equality can potentially increase PE class enjoyment among young girls.  相似文献   

An objective method for depicting team performance in elite professional rugby union     

Jones NM  James N  Mellalieu SD 《Journal of sports sciences》2008,26(7):691-700

Using a two-study approach, we examined a methodology for objectively depicting team performance and form in a professional rugby union side. Study 1 developed standardized indicators to examine a team's performance in a single match relative to their previous matches over a domestic season via a performance report and form chart. This resulted in standardized performance indicators that provided instant and coherent feedback on the team's performance relative to previous standards. Study 2 then utilized this methodology to compare a match between two professional sides, played the following season, to assess the extent to which the performance by one team affected that of the other. Comparison of the two teams' performances, for the match they played against each other, identified a drop in relative performance (against previous standards) for both teams on the same performance indicators. This appeared to be due to the match being a close, hard-fought contest particularly in the tackle and around the gain-line. The findings of the two studies suggest an accurate and viable methodology for depicting team performance that is superior to the global measures previously adopted. Presenting teams' current standardized performances (i.e. form) on a single visual scale also has utility for coaches within an applied setting. Future research should further investigate the effect of one team's performance on another through both individual and team outcomes.  相似文献   

Stressors in elite sport: a coach perspective   总被引：1，自引：1，他引：0  

Thelwell RC  Weston NJ  Greenlees IA  Hutchings NV 《Journal of sports sciences》2008,26(9):905-918

We examined the varying performance and organizational stressors experienced by coaches who operate with elite athletes. Following interviews with eleven coaches, content analysis of the data revealed coaches to experience comparable numbers of performance and organizational stressors. Performance stressors were divided between their own performance and that of their athletes, while organizational stressors included environmental, leadership, personal, and team factors. The findings provide evidence that coaches experience a variety of stressors that adds weight to the argument that they should be labelled as "performers" in their own right. A variety of future research topics and applied issues are also discussed.  相似文献   

Hearts in the fire, heads in the fridge: a qualitative investigation into the temporal patterning of the precompetitive psychological response in elite performers     

Mellalieu SD  Hanton S  Shearer DA 《Journal of sports sciences》2008,26(8):811-824

Retrospective perceptions and causal beliefs regarding the temporal patterning of precompetitive psychological responses were examined in 12 elite rugby union players. Composite sequence analysis resulted in a series of temporal networks to describe participants' cognitive, affective, and behavioural responses in a time-to-event paradigm. Match-related cognitions remained stable in the lead up to competition, while perceptions of physical symptoms peaked at the onset of performance. Affective responses were associated with feelings of anxiety and tension in the early temporal phases but excitement, confidence, and efficacy in team-mates directly before competition. Behavioural themes described activities associated with technical and physical preparation, familiarization with environmental conditions, and strategies to control activation states early on or directly before competition. The findings highlight the idiosyncratic and dynamic nature of the temporal patterning of precompetitive responses and the influence that perceptions of the team have upon individual preparation for performance. Implications are discussed in the context of the type and timing of intervention for developing individual and team preparatory routines.  相似文献   

Relationship of social physique anxiety to indicators of physique     

Monsma EV  Pfeiffer KA  Malina RM 《Research quarterly for exercise and sport》2008,79(3):417-422

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A season-long team-building intervention: examining the effect of team goal setting on cohesion     

Senécal J  Loughead TM  Bloom GA 《运动与训练心理学杂志》2008,30(2):186-199

The purpose of the current study was to determine whether the implementation of a season-long team-building intervention program using team goal setting increased perceptions of cohesion. The participants were 86 female high school basketball players from 8 teams. The teams were randomly assigned to either an experimental team goal-setting or control condition. Each participant completed the Group Environment Questionnaire (GEQ; Carron, Brawley, & Widmeyer, 2002; Carron, Widmeyer, & Brawley, 1985), which assessed cohesion at both the beginning and end of the season. Overall, the results revealed a significant multivariate effect, Pillai's trace F(12, 438) = 2.68, p = .002. Post hoc analyses showed that at the beginning of the season, athletes from both conditions did not differ in their perceptions of cohesion. However, at the end of the season, athletes in the team goal-setting condition held higher perceptions of cohesion than athletes in the control condition. Overall, the results indicated that team goal setting was an effective team-building tool for influencing cohesiveness in sport teams.  相似文献   

The influence of anxiety on visual attention in climbing   总被引：2，自引：0，他引：2  

Nieuwenhuys A  Pijpers JR  Oudejans RR  Bakker FC 《运动与训练心理学杂志》2008,30(2):171-185

The object of the current study was to investigate anxiety-induced changes in movement and gaze behavior in novices on a climbing wall. Identical traverses were situated at high and low levels on a climbing wall to manipulate anxiety. In line with earlier studies, climbing times and movement times increased under anxiety. These changes were accompanied by similar changes in total and average fixation duration and the number of fixations, which were primarily aimed at the holds used for climbing. In combination with these findings, a decrease in search rate provided evidence for a decrease in processing efficiency as anxiety increased.  相似文献