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1.
Simon J. Roberts James R. Rudd Matthew J. Reeves 《Journal of sports sciences》2020,38(11-12):1454-1464
ABSTRACT The present study examined the efficacy of a coaching curriculum, based on non-linear pedagogy, on improving attacking players’ individual learning objectives (ILOs) in elite-youth football. Participants included 22 attacking players (i.e., centre-forwards, wide-players and attacking midfield players) from a professional football academy in England. The players were randomly appointed to both control (CON) and intervention (INT) periods following baseline measures. The INT (non-linear) and CON (linear) periods were both designed to support the ILOs provided to each player as part of the elite player performance plan. The study adopted a randomised cross-over design and ILOs considered important for attacking players (i.e., strong foot finishing, weak foot finishing, 1-v-1 and decision-making) were evaluated using the Loughborough Shooting Skill Test. The results showed significant differences for INT in 1-v-1 (P< 0.02) and decision-making (P< 0.01). However, there were no significant differences for strong foot finishing, weak foot finishing or time taken. These results support non-linear pedagogy in developing 1-v-1 game play and decision-making but not for technical shooting proficiency. 相似文献
2.
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
3.
Matthew J. Madison 《Educational Measurement》2019,38(2):68-78
Recent advances have enabled diagnostic classification models (DCMs) to accommodate longitudinal data. These longitudinal DCMs were developed to study how examinees change, or transition, between different attribute mastery statuses over time. This study examines using longitudinal DCMs as an approach to assessing growth and serves three purposes: (1) to define and evaluate two reliability measures to be used in the application of longitudinal DCMs; (2) through simulation, demonstrate that longitudinal DCM growth estimates have increased reliability compared to longitudinal item response theory models; and (3) through an empirical analysis, illustrate the practical and interpretive benefits of longitudinal DCMs. A discussion describes how longitudinal DCMs can be used as practical and reliable psychometric models when categorical and criterion‐referenced interpretations of growth are desired. 相似文献
4.
ABSTRACTThis study operationalized Weick’s [(1988). Enacted sensemaking in crisis situations. Journal of Management Studies 25(4), 305–317 and (1993). The collapse of sensemaking in organizations: The Mann Gulch disaster. Administrative Science Quarterly, 38, 628–652] theory of enacted sensemaking to examine the communication processes associated with the Flint Water Crisis of 2014–2015. A content analysis of 389 emails and attachments from a total population of N?=?37,376 pages of publicly released e-mails and documents pertaining to Flint’s water issues, identified examples of failed sensemaking by government officials. These failures hastened and intensified a growing crisis of lead contamination and an outbreak of Legionnaires disease associated with Flint’s municipal water system. Analysis of email messages suggests that strong commitments by top leaders and limited capacity were important factors as were efforts to create and maintain consensus among officials. The Flint Water Crisis offers an important application of sensemaking theory and its utility for both organizational and risk communication scholars and for practical application. The authors emphasize the importance of questioning previous assumptions and commitments, insuring that communication practitioners are involved in decisions, and avoiding over reliance on image repair as a strategic response. 相似文献
5.
[目的/意义] 对美国《图书馆杂志》从1992年开始设立的"年度图书馆"奖的评选标准以及获奖图书馆的特色服务进行研究,旨在为我国图书馆开展特色化服务提供借鉴。[方法/过程] 通过网络调查法和案例分析法,对2000-2018年获得"年度图书馆"奖的19所图书馆开展的特色服务进行比较分析。[结果/结论] 获奖图书馆的服务特色:重视公民教育,强化教育职能;强调均等服务理念,体现人文关怀;提供多元社区信息服务,参与社区建设;树立品牌意识,打造品牌项目。对我国图书馆界的启示:科学合理地进行角色定位;积极参与社区贫困计划;强化特色服务品牌意识;拓宽合作领域。 相似文献
6.
[目的/意义] 系统回溯国内图书馆新媒体移动服务研究的理论基础与实践案例,总结理论研究进展和实践应用中的共性特征与优势经验,剖析当前实践中存在的问题,并针对相关问题提出解决方案。[方法/过程] 以"中国科讯"为研究案例,总结其在服务路径、服务方式与服务能力方面的实践探索。[结果/结论] "中国科讯"有效解决了国内图书馆新媒体服务定位不明确、不清晰、不全面的三个问题。图书馆需要加快传统新媒体移动服务逐步向集成多种功能的新媒体移动服务转变。 相似文献
7.
为建立绿色港口,实现港口的节能环保,对港口综合能源系统(port integrated energy system,PIES)的评价方法进行研究,提出一种主客观信息融合的PIES评价指标体系,将主观评价与数理统计模型进行结合,兼顾评价过程中的主客观因素,并采用基于马氏距离的统计检验方法对评分矩阵进行修正,实现对PIES的全面评价。通过青岛港董家口港区的调研数据,验证该方法的有效性。 相似文献
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9.
Science, Technology & Society (STS) graduate programs primarily train graduate students to work in tenure track academic jobs. However, there are not enough tenure track academic jobs to match the supply of STS graduate students, nor does every STS graduate student want to become an academic. As a start to addressing these challenges, we hosted workshops before the 2017 Society for the Annual Meeting of the Society Studies of Science and the 2018 ST Global conference. In those workshops, panelists with PhDs in STS and related fields and working in non-academic faculty careers such as government agencies, non-profit foundations, and industry emphasized that students must showcase how their skills are useful to non-academic organizations. The panelists offered a wealth of stories on how their STS perspective supported their careers, yet most had faced implicit and explicit mentoring from STS faculty that ran counter to their career aspirations. The conversations centered on reframing research and conveying to potential employers how their STS training would support their future careers. A takeaway point that resonated with many participants was the need for STS graduate programs to rethink how they market themselves, recruit students, and critically reflect upon the measures of success. By implicitly steering graduate students solely towards an academic career, STS graduate training will miss an opportunity to make a positive impact on society. 相似文献
10.
Matthew Farrow Christof Lutteroth Peter C. Rouse 《European Journal of Sport Science》2019,19(6):719-727
Purpose: To determine if: (i) mean power output and enjoyment of high-intensity interval training (HIIT) are enhanced by virtual-reality (VR)-exergaming (track mode) compared to standard ergometry (blank mode), (ii) if mean power output of HIIT can be increased by allowing participants to race against their own performance (ghost mode) or by increasing the resistance (hard mode), without compromising exercise enjoyment.Methods: Sixteen participants (8 males, 8 females, VO2max: 41.2?±?10.8 ml?1·kg?1·min?1) completed four VR-HIIT conditions in a partially-randomised cross-over study; (1a) blank, (1b) track, (2a) ghost, and (2b) hard. VR-HIIT sessions consisted of eight 60 s high-intensity intervals at a resistance equivalent to 70% (77% for hard) maximum power output (PMAX), interspersed by 60 s recovery intervals at 12.5% PMAX, at a self-selected cadence. Expired gases were collected and VO2 measured continuously. Post-exercise questionnaires were administered to identify differences in indices related to intrinsic motivation, subjective vitality, and future exercise intentions.Results: Enjoyment was higher for track vs. blank (difference: 0.9; 95% CI: 0.6, 1.3) with no other differences between conditions. There was no difference in mean power output for track vs. blank, however it was higher for track vs. ghost (difference: 5 Watts; CI: 3, 7), and hard vs. ghost (difference: 19 Watts; 95% CI: 15, 23).Conclusions: These findings demonstrate that VR-exergaming is an effective intervention to increase enjoyment during a single bout of HIIT in untrained individuals. The presence of a ghost may be an effective method to increase exercise intensity of VR-HIIT. 相似文献