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John Jerrim Luis Alejandro Lopez-Agudo Oscar D. Marcenaro-Gutierrez 《European Journal of Education》2020,55(2):248-260
The association between time devoted to homework and children's academic achievement has long been an issue of great debate. A small number of mainly correlational studies have been conducted into this issue in a primary school setting, but have produced somewhat mixed results. In this paper we contribute to this literature by investigating the relationship between time spent upon homework and children's outcomes across 24 countries. By using a student fixed-effects approach, capturing differences in homework time amongst the same student across different school subjects, we argue that our results are likely to be subject to less confounding than much of the existing literature. We find little evidence that the amount of homework time primary school children are assigned is related to their academic achievement. This holds true across a large number of countries, survives various robustness tests and does not vary by gender or socio-economic status. We interpret this finding as suggesting that the homework assigned to primary school pupils may not be adequate to produce a positive association, and needs be improved if this time-consuming activity is ever going to bring benefits for children's academic achievement. 相似文献
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Cherie Walker John Warmenhoven Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):146-162
Based on technological and analytical advances, the capability to more accurately and finitely examine biomechanical and skill characteristics of movement has improved. The purpose of this study was to use Inertial Measurement Units (IMUs) and Functional Principal Components Analysis (fPCA) to examine the role of movement variability (assessed via angular velocity), on 2 divers (1 international level; 1 national) performing the forward 3½ pike somersault dive. Analysis of angular velocity curves during ive-flight identified 5 fPCs, accounting for 96.5% of movement variability. The national diver’s scatter plots and standard deviation of fPC scores illustrated larger magnitudes of angular velocity variability across dive flight. For fPC1 and fPC3, magnitudes of SD variability were 282.6 and 201.5, respectively. The international diver illustrated more consistent angular velocity profiles, with clustering of fPCs scores (e.g., fPC1 & 3 = SD’s of 75.2 & 68.0). To account for lower variability in the international diver, the ability to better coordinate movement sequences and functionally utilise feedback in response to initiation of the somersault position is highlighted. Overall, findings highlight how both IMUs and fPCA can more holistically and finitely examine the biomechanical and skill characteristics of movement sequences with the capability to inform athlete development. 相似文献
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Qingli Lei Rose A. Mason Yan Ping Xin John L. Davis Marie David Catharine Lory 《Learning disabilities research & practice》2020,35(4):201-217
This single-case meta-analysis is the first to provide a quantitative synthesis of the published literature on mathematics word problem-solving intervention studies for English learners with learning disabilities and mathematics difficulties. A total of ten single-subject studies were included for analysis. The current study investigated the magnitude of the effect of mathematics interventions targeting the improvement of students’ mathematics word problem-solving performance, and analyzed variables that moderated this effect. Results indicate a moderate overall effect size of 0.81 (95% CI [0.71, 0.90]) on word problem-solving performance for English learners with learning disabilities and mathematics difficulties. Moderator variables such as the implementer of the interventions, instructional focus, and word problem-solving content significantly moderated the mathematics intervention effects. 相似文献
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John K. Rempel Lynn A. Rempel Dinh T.P. Hoa Le T. Vui Tran K. Long 《Child development》2020,91(2):e345-e364
A multifaceted, relationally focused intervention involving group and individual pre- and postnatal counseling, print resources, and community resources encouraged 390 fathers of newborn infants in Vietnam to responsively support mothers and work with them as a parenting team. Both partners completed questionnaires prebirth and 1-, 4-, and 9-months postbirth on measures of breastfeeding support, exclusive breastfeeding duration, relationship quality, and infant development. Compared to 412 comparison group couples, intervention couples evidenced greater father support, especially in terms of helping and responsiveness to the mother's needs. This support predicted longer exclusive breastfeeding duration, improved relationship quality, and higher levels of infant development at 9 months. Sensitively working together with mothers as a coordinated team enhanced couple's relationship functioning and improved children's developmental outcomes. 相似文献
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John Hutnyk 《Inter-Asia Cultural Studies》2018,19(1):129-147
This article examines a recurrent film motif across a number of South Asian films, mostly called Mela. It also offers some observations on melas, actual and allegorical, as represented in films but often seeming to exceed their containment in context so as to say more about the conviviality of life, where this is at issue, where life is at a juncture in need of resolution within the cycle of becoming. The issues of violence, loss, national identity, politics of interpretation and repetition in ideology are canvassed. While the essay is focused upon Mela films themselves, and South Asian film more broadly, it has of course been important to note work by scholars such as M. Madhava Prasad, Ashish Rajadhyaksha, Anjali Gera Roy, Tejaswini Niranjana, Gayatri Chakravorty Spivak and the help of my students, some of whom are named below. 相似文献
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Eric R. Muoz Jaclyn B. Caccese Brittany E. Wilson Kyle T. Shuler Fernando V. Santos Carolina T. Cabn John J. Jeka Dianne Langford Matthew B. Hudson 《运动与健康科学(英文)》2021,10(2):122
BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease. 相似文献