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141.
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Cemal Ozemek Mitchell H. Whaley W. Holmes Finch Leonard A. Kaminsky 《European Journal of Sport Science》2017,17(5):563-570
There have been many conflicting observations between the linear or curvilinear decline in maximal heart rate (HRmax) with age. The aim of this study was to determine if linear or curvilinear equations would better describe the decline in HRmax with age in individuals of differing cardiorespiratory fitness (CRF) levels. Treadmill cardiopulmonary exercise test (CPX) results from participants (1510 men and 1134 women; 18–76 years) free of overt cardiovascular disease were retrospectively examined using cross-sectional and longitudinal study designs. Participants completing ≥2 CPX with ≥1 year between test dates were included in the longitudinal analysis (325 men and 150 women). Linear and quadratic regressions were applied to age and HRmax for the whole cohort and respective CRF groups (high, moderate, and low, relative to age and gender normative values). To test for differences among linear, quadratic, and polynomial equations, the change in R2 (cross-sectional analysis) and Bayesian information criterion (BIC) (longitudinal analysis) from the linear to the more complex models were calculated. The quadratic or polynomial regression in the cross-sectional analysis, marginally improved the variance in HRmax explained by age compared to the linear regression for the whole cohort (0.2%), moderate fit group (0.3%), and low fit group (0.8%). With no improvements in the high fit group. BIC did not improve for any CRF category in the longitudinal analysis. In conclusion, the minimal differences among linear, quadratic, and polynomial equations in the respective CRF groups, emphasizes the use of linear prediction equations to estimate HRmax. 相似文献
144.
Mario Mali
ki Joseph Costello Juan Pablo Alperin Lauren A. Maggio 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)
IntroductionWhile early commenting on studies is seen as one of the advantages of preprints, the type of such comments, and the people who post them, have not been systematically explored.Materials and methodsWe analysed comments posted between 21 May 2015 and 9 September 2019 for 1983 bioRxiv preprints that received only one comment on the bioRxiv website. The comment types were classified by three coders independently, with all differences resolved by consensus.ResultsOur analysis showed that 69% of comments were posted by non-authors (N = 1366), and 31% by the preprints’ authors themselves (N = 617). Twelve percent of non-author comments (N = 168) were full review reports traditionally found during journal review, while the rest most commonly contained praises (N = 577, 42%), suggestions (N = 399, 29%), or criticisms (N = 226, 17%). Authors’ comments most commonly contained publication status updates (N = 354, 57%), additional study information (N = 158, 26%), or solicited feedback for the preprints (N = 65, 11%).ConclusionsOur results indicate that comments posted for bioRxiv preprints may have potential benefits for both the public and the scholarly community. Further research is needed to measure the direct impact of these comments on comments made by journal peer reviewers, subsequent preprint versions or journal publications. 相似文献
145.
Beatriz Lucas‐Molina Ariel A. Williamson Rosa Pulido Alicia Prez‐Albniz 《Psychology in the schools》2015,52(3):298-315
Peer harassment is a major social problem affecting children and adolescents internationally. Much research has focused on student‐to‐student harassment from either an individual or a multilevel perspective. There is a paucity of multilevel research on students’ relationships with the classroom teacher. The purpose of this study was to use a socioecological perspective to examine the relationships between individual student‐level characteristics, problematic teacher–student relationships, and student‐reported peer harassment. A total of 1,864 children (50.7% female) aged 8 to 13 years (M = 9.82, SD = 1.24), nested in 27 schools (58.2% public) in Spain, participated in the study. Ninety‐four homeroom teachers reported on teacher–student relationships, and students completed self‐report measures related to peer harassment and teacher–student relationships. Multilevel models showed that relationships between students and teachers exerted a varying degree of influence on classroom levels of peer harassment. Specifically, student‐reported teacher support was associated with diminished student‐reported peer victimization, whereas direct and indirect student‐reported teacher‐to‐student aggression was associated with increased peer victimization. Additionally, student‐reported student‐to‐teacher aggression and teacher‐to‐student aggression were associated with increased student‐reported peer aggression. Teacher‐reported variables at the classroom level, however, contributed little to student‐reported outcomes. Results are discussed in the context of future research on relationships between teachers and students. 相似文献
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147.
赋权少数族裔学生:一个干预框架 总被引:1,自引:0,他引:1
吉姆康明斯提出了一个理论框架来分析少数族裔学生学业失败的原因,以及之前曾尝试过的,诸如补偿教育和双语教育这样的教育改革相对缺乏成功的原因。这些尝试之所以没有成功是因为教育者和少数族裔学生之间的关系以及学校和少数族裔社区的关系都没有得到显著的改变。研究旨在为教育者提供一些改变这些关系,从而赋权学生,使得学生在学业上取得成功的方法。 相似文献
148.
149.
Aïmen Khacharem 《Journal of sports sciences》2017,35(12):1204-1210
Comprehension of a narrated diagram entail complex cognitive processing as learner is challenged to extract the orally evoked information. The present experiment examined the effects of 2 different forms of attention guidance – bottom-up and top-down – on comprehension performance, cognitive load investment, and motivation to learn, using a 2 × 2 mixed design with factors “Expertise” (Expert vs. Novice) and “Condition” (no-signal, circle, segment). The results revealed an expertise reversal effect indicating that the incorporation of visual signals in diagram is effective for novice learners but partially reverses and becomes ineffective for more experienced learners (even though they invested less mental effort and reported higher level of motivation in the segmented condition). The findings suggested that the effectiveness of instructional guidance depends heavily on levels of prior knowledge. 相似文献
150.
Rocío Cupeiro Miguel A. Rojo-Tirado Cristina Cadenas-Sanchez Enrique G. Artero Ana B. Peinado Idoia Labayen 《Journal of sports sciences》2020,38(13):1506-1515
ABSTRACT The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F10,5996 = 369.64; p < 0.001, ηp 2 = 0.381) and of quarter (Wilks’ λ = 0.874; F15,8276.6 = 27.67; p < 0.001; ηp 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers. 相似文献