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181.
This study investigated the effects of a peer teaching procedure, combined with student letter-writing activities, on the acquisition and generalization of capitalization skills. Three students, aged 9 years, obtained instruction from peer partners that included (a) an introduction and review of capitalization rules, (b) feedback on each participant's previous capitalization work, and (c) guided and independent practice on sentences that required capitalization. All three students demonstrated acquisition of the capitalization rules after participating in the teaching sessions with one or two peer partners. In addition, there were increases in capitalization accuracy in participants' letters to peers who did not serve as teaching partners, thus demonstrating a measure of across-peer (stimulus) generalization. Mixed results were obtained on a response generalization task (sentence writing). Finally, sentencing-writing activities also showed that two of the peer partners substantially improved their use of capitalization skills as a result of teaching the target students.  相似文献   
182.
The article presents the implementation and findings of a successful collaborative effort with the Oklahoma State Regents for Higher Education (OSRHE), Tulsa Community College (TCC), and two local public school districts, Tulsa Public Schools (TPS) and Union Public Schools (UPS). Known as EXCELerate, it's a five-semester dual enrollment pilot program that received state policy exceptions for juniors and seniors to enroll in dual enrollment courses and supportive resources from the participating agencies. Whereas the traditional dual enrollment student is White and college-going, the program's intent was to increase the number of high school students who may be first-generation, lower-socioeconomic, ethnic or non-ethnic. The article identifies three major barriers to successful dual enrollment and completion: state policy, financial issues, and transportation. It also examines how these barriers were eliminated through a collaborative effort. The results demonstrate that over 87% of the juniors and seniors persisted over the semesters, and enrollment tripled among African American and Latino students. The article is constructed to benefit further research and practical application for urban and rural community colleges.  相似文献   
183.
This study sought to compare the kinetics and kinematics data in a group of habitual shod runners when running in traditional running shoes and newly designed minimalist shoes with lug platform. This novel footwear design claims to simulate barefoot running and reduce energy loss during impact. We compared footstrike angle (FSA), vertical average (VALR) and instantaneous (VILR) loading rates, energy loss and initial vertical stiffness between two shoe conditions. Runners demonstrated a decreased FSA while running in minimalist shoes with lug platform than traditional shoes (= 0.003; Cohen’s = 0.918). However, we did not observe a landing pattern transition. VALR and VILR between two footwear conditions showed no significant difference (= 0.191–0.258; Cohen’s = 0.304–0.460). Initial vertical stiffness (= 0.032; Cohen’s = 0.671) and energy loss (= 0.044; Cohen’s = 0.578) were greater when running in minimalist shoes with lug platform. The results show that minimalist shoes with lug platform reduce the FSA but may not lead to a landing pattern switch or lower vertical loading rates. Interestingly, the new shoe design leads to a greater energy loss than traditional running shoes, which could be explained by a higher initial vertical stiffness.  相似文献   
184.
Prospective application of serum cytokines, lipopolysaccharide (LPS), and heat shock proteins (eHSPs) requires reliable measurement of these biomarkers that can signify exercise-induced heat stress in hot conditions. To accomplish this, both short-term (7 day) reliability (at rest, n = 12) and the acute responsiveness of each biomarker to exercise in the heat (pre and post 60-min cycling, 34.5°C and 70% RH, n = 20) were evaluated. Serum was analysed for the concentration of C-reactive protein (CRP), interleukin-6 (IL-6), heat shock protein 72 (eHSP72), immunoglobulin M (IgM) and LPS. Test–retest reliability was determined as the coefficient of variation (CV). Biomarkers with the least short-term within-participant variation were IL-6 (19%, ±20%; CV, ±95% confidence limits (CL)) and LPS (23%, ±13%). Greater variability was observed for IgM, eHSP72 and CRP (CV range 28–38%). IL-6 exhibited the largest increase in response to acute exercise (95%, ±11%, P = < 0.001) and although CRP had a modest CV (12%, ±7%), it increased substantially post-exercise (P = 0.02, ES; 0.78). In contrast, eHSP72 and LPS exhibited trivial changes post-exercise. It appears variation of common inflammatory markers after exercise in the heat is not always discernible from short-term (weekly) variation.  相似文献   
185.
Broader contextual factors that influence concussion management have tended to be overlooked. To address this, the present study used a sociotechnical systems approach to identify perceived responsibilities and applied strategies for three domains of concussion management (i.e., prevention, identification and treatment). Participants were 118 members of the community rugby union system in Australia (69.2% male). Participants from throughout the rugby system (e.g., players, parents, coaches, club management) were asked open-ended questions about their perceived responsibilities and the strategies they use for concussion management. It was found that (a) proper training, technique correction and education were recurrent prevention themes; (b) the majority of key stakeholders felt that they could consistently identify concussion; however, medical aids (medics) were the only system actors who stated a responsibility to use standardised concussion assessment measures and (c) less than one third of the respondents indicated their involvement in treating concussion. This study identifies specific junctures in the system that prevents effective concussion management strategies. A sociotechnical systems approach improves the understanding of concussion prevention, and management beliefs and behaviours.  相似文献   
186.
Multistage, ultra-endurance events in hot, humid conditions necessitate thermal adaptation, often achieved through short term heat acclimation (STHA), to improve performance by reducing thermoregulatory strain and perceptions of heat stress. This study investigated the physiological, perceptual and immunological responses to STHA prior to the Marathon des Sables. Eight athletes (age 42 ± 4 years and body mass 81.9 ± 15.0 kg) completed 4 days of controlled hyperthermia STHA (60 min·day?1, 45°C and 30% relative humidity). Pre, during and post sessions, physiological and perceptual measures were recorded. Immunological measures were recorded pre-post sessions 1 and 4. STHA improved thermal comfort (P = 0.02), sensation (P = 0.03) and perceived exertion (P = 0.04). A dissociated relationship between perceptual fatigue and Tre was evident after STHA, with reductions in perceived Physical (P = 0.04) and General (P = 0.04) fatigue. Exercising Tre and HR did not change (P > 0.05) however, sweat rate increased 14% (P = 0.02). No changes were found in white blood cell counts or content (P > 0.05). Four days of STHA facilitates effective perceptual adaptations, without compromising immune status prior to an ultra-endurance race in heat stress. A greater physiological strain is required to confer optimal physiological adaptations.  相似文献   
187.
Purpose: The purpose of this study was to conduct a systematic review of classroom-based physical activity interventions that integrate academic content and assess the effectiveness of the interventions on physical activity, learning, facilitators of learning, and health outcomes. Method: Six electronic databases (ERIC, PubMed, Google Scholar, Science Direct, Cochrane Library, and EMBASE) and reference lists were searched for English-language articles, published January 1990 through March 2015, reporting classroom-based interventions that deliberately taught academic content using physically active teaching methods for at least 1 week duration, with physical activity, health, learning, or facilitators-of-learning outcomes. Two authors reviewed full-text articles. Data were extracted onto an Excel spreadsheet, and authors were contacted to confirm accuracy of the information presented. Results: Fifteen studies met the inclusion criteria. Six studies reporting on physical activity levels were found to have medium-to-large effect sizes. All 4 studies reporting learning outcomes showed positive effects of intervention lessons. Teachers and students were pleased with the programs, and enhanced on-task behavior was identified (n = 3). Positive effects were also reported on students’ body mass index levels (n = 3). Conclusions: Physically active academic lessons increase physical activity levels and may benefit learning and health outcomes. Both students and teachers positively received and enjoyed these teaching methods. These findings emphasize the need for such interventions to contribute toward public health policy.  相似文献   
188.
Purpose: This study investigated the effect of summer camp session context on Russian girls’ physical activity (PA). Method: Girls (n = 32, Mage = 10.7 years, SD = 0.6 years) from a resident summer camp taking place in the Vologda Region of Russia were exposed to 1 session context/day (i.e., free play, organized with no choice, organized with choice) on Wednesday, Thursday, and Friday for 3 weeks, with the context order counterbalanced across the 3 weeks. The organized session sport/game changed weekly. The primary outcome was accelerometer-assessed PA. Repeated-measures mixed models were used to analyze all outcome data. Results: Findings showed that girls spent a greater percentage of session time (%time) in moderate-to-vigorous PA (p < .001; effect sizes between free play and organized with no choice and organized with choice, respectively = .60, .42) and moderate PA (p < .001; effect size = .57, .39) and a lower %time in light PA (p < .001; effect size = .55, .52) in organized PA contexts compared with free play. Conclusions: This study provides novel findings in a Russian setting, suggesting that a well-planned, organized camp session can elicit higher PA levels in girls, relative to a free-play session.  相似文献   
189.
The present study describes the development and validation of an instrument to measure volition in the exercise context. Volition describes an individual’s self-regulatory mental processes that are responsible for taking and maintaining a desirable action (e.g., exercising regularly). The scale structure was developed in an exploratory factor analysis which resulted in a reliable structure of the following six factors: Volitional Inhibition—Reasons, Volitional Inhibition—Postponing Training, Volitional Facilitation—Self-Confidence, Volitional Inhibition—Unrelated Thoughts, Volitional Inhibition—Approval From Others, and Volitional Facilitation—Coping with Failure. A sound theoretical explanation for these six factors is based on the Personal System Interaction Theory. This six-factor structure was also confirmed in a new sample in a confirmatory factor analysis, delivering an 18-item questionnaire with strong model fit and good internal consistency. In addition, the Volition in Exercise Questionnaire showed convergent validity because it was able to predict exercise participation. It showed incremental validity by explaining additional variance to the Sport Motivation Scale’s well-established predictors of exercise participation.  相似文献   
190.
The purpose of this study was to compare the validity and reliability of three short physical activity self-report instruments to determine their potential for use with university student populations. The participants (N = 155; 44.5% male; 22.9 ± 5.13 years) wore an accelerometer for 9 consecutive days and completed a single-item measure, the a brief two item measure and the International Physical Activity Questionnaire—Short Form questionnaires on day 1 and 9. Correlations between self-reported and accelerometer derived moderate-to-vigorous physical activity levels were moderate for the International Physical Activity Questionnaire—Short Form, while poor for the single-item measure and the a brief two item measure. The agreement level was high with the International Physical Activity Questionnaire—Short Form (77.4%) and moderate for both the single-item measure (45.2 %) and a brief two item measure (44.5 %). The intraclass correlations between the two administrations were moderate to strong across all measures (0.52–0.70) in 133 participants. The International Physical Activity Questionnaire—Short Form is the most suitable of these three self-report instruments for use with this population due to higher correlations and levels of agreement with accelerometry.  相似文献   
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