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Sixty-one children, originally identified at the beginning of kindergarten on the basis of 4 distinct clusters of observable classroom behavior, were evaluated at completion of first grade. Teacher ratings and individual achievement test scores partially confirmed the predictive validity of the original clusters. Children in the nonrisk cluster continued to do well, while children in the high-risk cluster were still doing poorly in some areas. An unexpected finding was that children in another cluster, originally seen as nonrisk, also seemed to be in some difficulty. Concerns about specific aspects of observable behavior were discussed. 相似文献
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Leonardo S. Fortes Dalton De Lima-Junior Lenamar Fiorese José R. A. Nascimento-Júnior Arnaldo L. Mortatti Maria E. C. Ferreira 《Journal of sports sciences》2020,38(5):552-558
ABSTRACTThe objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (p < .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes. 相似文献
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Pornography use is often associated with less-progressive sex-role attitudes, such as endorsement of a sexual double standard between heterosexual partners, but the process by which this relationship occurs is still largely unexamined. The present study was conducted to examine how perceptions about pornography may play a role in the relationship between pornography use and sex-role attitudes. Perceived general acceptance and perceived influence of pornography on most people partially mediated the relationship between pornography use and sex-role attitudes. The more participants reported using pornography, the more they believed pornography was generally accepted and had a positive influence; however, conversely to what was hypothesized, the more positive they perceived pornography’s influence, the less likely they were to report sex-role attitudes that endorse a sexual double standard. 相似文献
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K. R. Shivanna 《Resonance》2016,21(11):1007-1018
After the pollen grain reaches the stigma through outsourced agents (pollinators), the next step before fertilization is to select the right type of pollen. Similar to a marriage in human beings, fiowering plants also have evolved elaborate screening process to select the right pollen grains and to reject the wrong ones. Even after initial screening for the right pollen, the pistil imposes a tough competition amongst them, comparable to a swayamvara of Indian mythology, to select the best available pollen. Flowering plants have evolved into a matriarchal society. The selection of the male partner is totally the prerogative of the mother (pistil); the boy (pollen grain) and the girl (ovule) has no say in this selection. 相似文献
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Jordan J. Smith Philip J. Morgan Ronald C. Plotnikoff David F. Stodden David R. Lubans 《Journal of sports sciences》2016,34(8):772-779
The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered “at-risk” of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys. 相似文献
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