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1.
The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (= -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (= 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness.  相似文献   
2.
Abstract

Carnosine was originally discovered in skeletal muscle, where it exists in larger amounts than in other tissues. The majority of research into the physiological roles of carnosine have been conducted on skeletal muscle. Given this and the potential for muscle carnosine content to be increased with supplementation, there is now a large body of research examining the ergogenic effects (or otherwise) of carnosine. More recent research, however, points towards a potential for carnosine to exert a wider range of physiological effects in other tissues, including the brain, heart, pancreas, kidney and cancer cells. Taken together, this is suggestive of a potential for carnosine to have therapeutic benefits in health and disease, although this is by no means without complication. Herein, we will provide a review of the current literature relating to the potential therapeutic effects of carnosine in health and disease.  相似文献   
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Through this study we compared different informants and different behavior screening tools that are available to screen for behavioral and emotional risk. We examined screening results from 100 students from a high school with a high achiever's magnet program in the Southeastern United States (school demographics: 71% female and 79% black, non-Hispanic). This school conducted behavior screening using both teacher-report via the Student Risk Screening Scale, Internalizing/Externalizing (SRSS-IE) and student report via the Strengths and Difficulties Questionnaire (SDQ). Nonparametric correlation tests were conducted between the SRSS-IE and SDQ externalizing and internalizing scores. Generalized linear regression models were created based on the data (demographics, internalizing, and externalizing scores on both screening tools) to model the two count outcomes (office discipline referrals [ODRs] and absences). Diagnostic accuracy metrics were generated from the scores on both the SRSS-IE and SDQ with the outcome measures (ODRs and absences). Externalizing scores on both screening tools had statistically significant low correlations. The ODR model contained two predictors: externalizing score on the SRSS-IE and internalizing score on the SDQ, while the absence model contained grade and the externalizing score on the SDQ. The highest accuracy and agreement values were seen between students with elevated risks on both screening measures and ODRs. The results confirmed that teacher and student reporting, as well as different screening tools, will result in some different students being identified. The choice of informant and screening tools should be dependent on the needs and resources of the school.  相似文献   
5.
Working memory training improves children's cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms. This was investigated in 32 typically developing children aged 10–14 years (19 girls and 13 boys) using a randomized controlled design and multi-modal magnetic resonance imaging (Devon, UK; 2015–2016). Training improved working memory performance and increased intrinsic functional connectivity between the bilateral intraparietal sulci. Furthermore, improvements in working memory were associated with greater recruitment of the left middle frontal gyrus on a complex span task. Repeated engagement of fronto-parietal regions during training may increase their activity and functional connectivity over time, affording greater working memory performance. The plausibility of generalizable cognitive benefits from a neurobiological perspective and implications for neurodevelopmental theory are discussed.  相似文献   
6.
ABSTRACT

Background and Context

Sports and technology are often pitted as being at odds with one another. While there are several educational activities that make reference to sports we seldom see sports used as an authentic context for learning computing.  相似文献   
7.
ABSTRACT

This systematic review and meta-analysis aimed to determine differences in body compositionn between playing standard and age in male rugby union and rugby league athletes. The MOOSE (Meta-analysis of Observational Studies in Epidemiology) guidelines for design, implementation, and reporting were followed. Studies were required to be in male rugby union or league and have body composition as the primary or secondary outcome. Data was required to be presented separately for positional groups and body composition presented as whole-body. A systematic search was performed in PubMed, Cochrane Library, MEDLINE, SPORTDiscus, and CINHAHL via EBSCOhost. 57 studies were included for meta-analysis. Results highlighted significantly higher fat-free mass in senior elite than senior sub-elite or junior elite athletes for all RU and RL forwards. Small and non-significant differences were found in fat mass between rugby union playing standards and age categories. Rugby league senior elite forwards had less fat mass than junior elite forwards. Practitioners should prioritise training and nutritional strategies that maximise fat-free mass development, especially in junior elite cohorts.  相似文献   
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Supporting young people with global crises mitigation strategies is essential, yet loaded with ethical dilemmas for the educator. This study explores whether young people will make ethical decisions regarding the sustainability of food choice in schools, and based on the processes identified, what educators’ needs are in supporting transformative learning. This study is the first of its kind, where young people under the age of 14 have been tasting edible insects and discussing their role in a more sustainable diet. The article draws on mixed-method research with over 180 young people and their teachers in three schools in Wales and examines responses to a possible introduction of edible insects into school canteens. Highlighted is the complexity of sustainable food choices—likely to be identifiable with other young people and educators in western countries. The article considers how educators and policy makers may need to frame routes to positive sustainable action and the associated impacts these may have on personal, social, political and environmental spheres.  相似文献   
10.
Numerous studies suggest an association between language and executive function (EF), but evidence of a developmental relationship remains inconclusive. Data were collected from 75 deaf/hard-of-hearing (DHH) children and 82 hearing age-matched controls. Children were 6–11 years old at first time of testing and completed a battery of nonverbal EF tasks and a test of expressive vocabulary. These tasks were completed again 2 years later. Both groups improved their scores on all tasks over this period. DHH children performed significantly less well than hearing peers on some EF tasks and the vocabulary test at both time points. Cross-lagged panel models showed that vocabulary at Time 1 predicted change in EF scores for both DHH and hearing children but not the reverse.  相似文献   
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