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91.
Abstract

The purpose of this study was to compare the effectiveness of learning between two distributions of practice in archery and badminton classes. Each activity was divided into two groups based on the distribution of practice used. The “t” test of the significance of the difference between means was used to make comparisons between groups relative to the effectiveness of the two practice distributions of learning as measured by gain in selected criteria. The results seemed to indicate that more effective learning in archery took place under relatively massed practice while in badminton wider distribution of practice produced more rapid learning.  相似文献   
92.
Background:Little is known about exercise cardiac power(ECP),defined as the ratio of directly measured maximal oxygen uptake with peak systolic blood pressure during exercise,on heart failure(HF)risk.We examined the association of ECP and the risk of HF.Methods:This was a population-based cohort study of 2351 men from eastern Finland.The average time to follow-up was 25 years.Participants participated at baseline in an exercise stress test.A total of 313 cases of HF occurred.Results:Men with low ECP(<9.84 mL/mmHg,the lowest quartile)had a 2.37-fold(95%confidence interval(95%CI):1.68-3.35,p<0.0001)hazards ratio of HF as compared with men with high ECP(>13.92 mL/mmHg,the highest quartile),after adjusting for age.Low ECP was associated with a 1.96-fold risk(95%CI:1.38-2.78,p<0.001)of HF after additional adjustment for conventional risk factors.After further adjustment for left ventricular hypertrophy,the results hardly changed(hazards ratio=1.87,95%CI:1.31-2.66,p<0.001).One SD increase in ECP(3.16 mL/mmHg)was associated with a decreased risk of HF by 28%(95%CI:17%-37%).Conclusion:ECP provides a noninvasive and easily available measure from cardiopulmonary exercise tests in predicting HF.However,ECP did not provide additional value over maximal oxygen uptake.  相似文献   
93.
摘要:心血管疾病(CVD)一直是全世界最主要的死因。由于CVD等慢性疾病对健康的威胁越来越大,有必要开展生活方式干预项目以控制这些疾病的危险因素。本研究的目的是评估美国的重要慢病干预项目—HELPS治疗型生活方式改变(TLC)项目对减少CVD危险因素和其他慢性疾病的有效性。方法:140位大学教职工参加为期12周的HELPS TLC项目,干预前后用配对t检验对其体重、BMI、腰围(WC)、6分钟步行距离(6MWD)、空腹血脂和血糖进行测定和比较。结果:干预后6MWD显著增加,总胆固醇(TC)和WC显著下降。对“高危”参与者进一步分析显示:BMI(-1.5±0.5,-3.9%)、TC(- 22.8±4.0,-9.0%)、LDL(- 14.1±4.9,9.3%)和血糖(-6.9±2.2,-6.1%)均显著下降;男性腰围(-4.5±0.8,-10%)显著减小,女性未见显著改变(-1.5±0.5,-4.0%)。此外,体重的变化与TC(r=0.43)、LDL(r=0.35)和血糖(r=0.44)的变化均显著相关。结论:参加12周的生活方式干预项目可以使CVD危险因素减少,特别是在CVD“高危”个体中。HELPS TLC项目的远期效果还待进一步深入研究。  相似文献   
94.
The aim of the present study was to examine the relationship between the performance heart rate during an ultra-endurance triathlon and the heart rate corresponding to several demarcation points measured during laboratory-based progressive cycle ergometry and treadmill running. Less than one month before an ultra-endurance triathlon, 21 well-trained ultra-endurance triathletes (mean +/- s: age 35 +/- 6 years, height 1.77 +/- 0.05 m, mass 74.0 +/- 6.9 kg, = 4.75 +/- 0.42 l x min(-1)) performed progressive exercise tests of cycle ergometry and treadmill running for the determination of peak oxygen uptake (VO2peak), heart rate corresponding to the first and second ventilatory thresholds, as well as the heart rate deflection point. Portable telemetry units recorded heart rate at 60 s increments throughout the ultra-endurance triathlon. Heart rate during the cycle and run phases of the ultra-endurance triathlon (148 +/- 9 and 143 +/- 13 beats x min(-1) respectively) were significantly (P < 0.05) less than the second ventilatory thresholds (160 +/- 13 and 165 +/- 14 beats x min(-1) respectively) and heart rate deflection points (170 +/- 13 and 179 +/- 9 beats x min(-1) respectively). However, mean heart rate during the cycle and run phases of the ultra-endurance triathlon were significantly related to (r = 0.76 and 0.66; P < 0.01), and not significantly different from, the first ventilatory thresholds (146 +/- 12 and 148 +/- 15 beats x min(-1) respectively). Furthermore, the difference between heart rate during the cycle phase of the ultra-endurance triathlon and heart rate at the first ventilatory threshold was related to marathon run time (r = 0.61; P < 0.01) and overall ultra-endurance triathlon time (r = 0.45; P < 0.05). The results suggest that triathletes perform the cycle and run phases of the ultra-endurance triathlon at an exercise intensity near their first ventilatory threshold.  相似文献   
95.
Landing with the knee in a valgus position is recognized as a risk factor for anterior cruciate ligament (ACL) injury. Using linear and non-linear regression analyses, the purpose of this study was to examine the correlation between two-dimensional (2D) knee valgus and three-dimensional (3D) knee kinematics measured during a jump landing task. Twenty-eight female collegiate athletes participated. All participants were required to perform a continuous jump test. The average maximum angles of abduction and internal tibial rotation during landing were measured using the Point Cluster Technique. Average peak knee valgus angle was measured using a 2D approach. Linear and non-linear regression analyses between 2D valgus and 3D knee abduction, and between 2D valgus and 3D internal tibial rotation, were performed. The R2 value between 2D valgus and 3D knee abduction was significantly different from zero and had a moderate correlation for all models, whereas the R2 value between 2D valgus and 3D internal tibial rotation was not significantly different from zero. The 2D approach could be used to screen a specific group of individuals for risk of ACL injury; however, using frontal plane 2D analysis of valgus motion to evaluate internal tibial rotation is not advised.  相似文献   
96.
国家精品课程项目是中国高等教育领域的一项重大项目,旨在通过开放教育资源建设提升本科教学质量。西方研究者普遍认为,国家精品课程是受美国麻省理工学院开放课件项目(简称MIT OCW)启发的一种开放课程形式。本文以中国国家精品课程项目为研究主题,围绕项目的目标、运作实施、发展历程、启动背景、与MIT OCW的联系和差异等问题,采用文献研究、正式访谈、非正式交流等研究方法收集和分析研究资料,聚焦研究问题。论文提出基于开放教育资源的目的进行分类,将开放教育资源实践模式分为转变性的建设、直接使用、重新使用和公开/咨询四种类型,并利用这一分析框架讨论了中国国家精品课程项目和MIT OCW项目的异同。文章认为,国家精品课程项目是中国独立应对国内挑战的决策,而不是引进的开放课程模式;中国和北美地区对大学教学的认识非常不同,中国高等教育既借鉴了历史上法国重教学和德国重研究的大学模式,又结合了利用榜样、注重团队建设提升质量的传统。这使得国家精品课程项目具有独特的体制优势,与其他开放教育资源项目相区别,而且难以在北美地区执行,但这也有助于启发我们重新思考北美的大学教学及其改革。  相似文献   
97.
Every day, students and instructors are faced with the decision of when to study information. The timing of study, and how it affects memory retention, has been explored for many years in research on human learning. This research has shown that performance on final tests of learning is improved if multiple study sessions are separated—i.e., “spaced” apart—in time rather than massed in immediate succession. In this article, we review research findings of the types of learning that benefit from spaced study, demonstrations of these benefits in educational settings, and recent research on the time intervals during which spaced study should occur in order to maximize memory retention. We conclude with a list of recommendations on how spacing might be incorporated into everyday instruction.  相似文献   
98.
In this paper social semiotics, and systemic functional linguistics in particular, are used in order to identify registers of digital literacy in the use of virtual learning environments. The framework of social semiotics provides means to systemize and discuss digital literacy as a linguistic and semiotic issue. The following research question was investigated in the paper: What different registers of digital literacy could be identified when students and teachers communicate and interact in a VLE?The research question was answered by, initially, an application of social semiotics to virtual learning environments, and its relation to the knowledge domains of everyday, specialized and reflexive digital literacy. This application was then further developed, using an analysis of a course specific use of a virtual learning environment in a case study. The study identified discrepancies between the digital literacies of teachers, designers and students. These discrepancies mean that a shared semiotic register was sometimes difficult to maintain. The conclusion is that the designers and teachers as co-designers of virtual learning environments need a better understanding of everyday digital literacy in order to design more sufficient learning environments. The paper shows that digital literacy must be considered as a situated practice, and that it concerns functional and communicative competencies rather than acquiring a set of technical skills.  相似文献   
99.
Abstract: Food science laboratory courses are traditionally taught as a series of preplanned laboratories with known endpoints. In contrast, inquiry‐guided (IG) laboratories allow students to ask questions, think through problems, design experiments, then adapt and learn in response to unexpected results. This study examined the effects of converting the course, “Analytical Techniques in Food and Bioprocessing Sciences” from a traditional approach (2008 to 2010 data) to an IG approach (2011 data) by assigning teams of 2–3 students a food and a set of 5 analyses to conduct over the course of the semester. Students were required to choose and justify the use of specific methods for each analysis, as well as to develop a supply list and a budget for the semester‐long project. During the semester, students were required to post and discuss their weekly progress with the instructor, teaching assistants, and the rest of the class using an online discussion forum. At the end of the semester, students were required to present the results of their analysis in both oral and written formats. Overall course grades were significantly higher (P≤ 0.05) using IG in 2011 compared to 2010 and 2009, but not to 2008 grades. Numerical course evaluations for the instructor, overall course, and lab, as well as written course evaluations all significantly (P≤ 0.05) improved. This suggests that an IG approach may measurably improve student performance in terms of course grades and the ability to complete semester long projects. It may also increase student satisfaction with the course, as measured by numerical and written end of semester surveys.  相似文献   
100.
The perceptions, knowledge, and opinions of 104 teachers of students with learning disabilities regarding medication used with their students were investigated. The students' doctors were perceived as the professionals primarily responsible for making the decision to have the student either placed on or taken off medication. The teachers indicated that global impressions and direct behavioral observations were used to assess the effects of medication but that they would prefer to use behavioral observations and rating scales. Hyperactivity and delusions/hallucinations were perceived as the problems most likely to lead to medication. Less than 15% of the teachers indicated that their professional preservice training had provided them with sufficient information on the use of medication for children with behavior problems, and less than 20% had a similar opinion regarding their inservice training on the same topic.  相似文献   
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