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1.
Evidence of the internal consistency of standard-setting judgments is a critical part of the validity argument for tests used to make classification decisions. The bookmark standard-setting procedure is a popular approach to establishing performance standards, but there is relatively little research that reflects on the internal consistency of the resulting judgments. This article presents the results of an experiment in which content experts were randomly assigned to one of two response probability conditions: .67 and .80. If the standard-setting judgments collected with the bookmark procedure are internally consistent, both conditions should produce highly similar cut scores. The results showed substantially different cut scores for the two conditions; this calls into question whether content experts can produce the type of internally consistent judgments that are required using the bookmark procedure.  相似文献   
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ABSTRACT

This study aimed to examine the effects of two jump squat (JS) training programs involving different loading ranges in under-20 soccer players during a preseason period. Twenty-three elite young soccer players performed sprint speed (at 5-, 10-, and 20-m), change-of-direction (COD) speed, JS peak-power (PP), and countermovement jump (CMJ) tests pre and post four weeks of training. Athletes were pair-matched in two groups according to their optimum power loads (OPL) as follows: lower than OPL (LOPL; athletes who trained at a load 20% lower than the OPL) and higher than OPL (HOPL; athletes who trained at a load 20% higher than the OPL). Magnitude-based inferences were used to compare pre- and post-training measures. Meaningful increases in the PP JS were observed for both groups. Likely and possible improvements were observed in the 5- and 10-m sprint velocity in the LOPL group. Meanwhile, possible and likely improvements were observed in the CMJ, 5- and 10-m sprint velocity, and COD speed in the HOPL group. Overall, both training schemes induced positive changes in athletic performance. Soccer coaches and sport scientists can implement the JS OPL-based training schemes presented here, either separately or combined, to improve the physical performance of youth soccer players.  相似文献   
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Few data exist on gender-typed and gender-segregated play in hunter-gatherer societies, despite their unique demographic and cultural features which may influence children’s gendered play. Using naturalistic observations of Hadza (N = 46, 41% female) and BaYaka (N = 65, 48% female) hunter-gatherer 3- to 18-year-olds from Tanzania and the Republic of Congo, we showed that access to playmates was negatively associated with playing in mixed-gender groups. Young boys did not engage in more rough-and-tumble play than girls, but adolescent boys participated in this type of play more than adolescent girls. Children were also more likely to participate in work-themed play which conformed to gender norms within their society. Findings are discussed within the context of gendered division of labor, child autonomy, and demography.  相似文献   
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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   
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School is a hyperviolent space for Black students and in particular for Black girls. Black girls continue to be adultified, criminalized, and spirit-murdered by educators who enact racially discriminatory school disciplinary policies. Using literature from racial microaggressions and antiblackness, we introduce a model that we refer to as “antiblack aggressions” to examine the disciplinary experiences of two Black girls who were at the center of a violent assault by a White male School Resource Officer at Spring Valley High School. We provide an analysis of South Carolina's Disturbing Schools Law, and we discuss how an antiblack aggressions model can challenge traditional notions of peace, law, and justice for Black girls in school.  相似文献   
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Ronald Barnett's modern classic Realizing the University in an Age of Supercomplexity (published December 1999), has had a crucial impact internationally on the field of Higher Education research and development since the book was published now nearly 20 years ago. Bridging an academic oeuvre across almost 30 years with close to 30 published volumes, Realizing the University in an Age of Supercomplexity plays an important role in the development and transformation of Barnett's social theory of Higher Education into a social philosophy of Higher Education. In the book Barnett performs an important move from a focus on knowledge and epistemology to a focus on being and ontology in relation to Higher Education practices. Barnett shifts his fundamental perspective and view on the relation between universities and the wider society from one of caution and worry to a perspective of hope and vision that fully embraces the future of Higher Education. This way, Realizing the University in an Age of Supercomplexity has not only paved the way for Barnett's own development of a social philosophy of Higher Education, but also contributed invaluably to the rise and maturing of philosophy of Higher Education as a research field in its own right.  相似文献   
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Recent theories suggest that negative effects of fatigue on performance are determined by perception of effort and motivation rather than being directly caused by reaching physiological limits. In the current experiment, the influence of motivation on fatigue-induced decrements in soccer performance was experimentally investigated. Sixty amateur soccer players performed a validated soccer-passing test before and after a fatigue protocol. Results showed that players’ motivation and performance decreased after the fatigue protocol for players in the control group. In contrast, players in the motivation group (i.e., with motivation experimentally induced after the fatigue protocol) were able to uphold their motivation and increase their performance. These results indicate that motivation plays a crucial role in performance under fatigue, as fatigue-induced decrements in soccer passing performance can be counteracted by high levels of motivation. Future research may explore the limits of this counteracting effect and extend findings to other relevant performance aspects.  相似文献   
9.
The analysis of sport performance in competitive contexts has become synonymous with the use of a range of software applications and hardware e.g. heart rate monitors and gps systems. With the prevalence of technology in mind, a small but growing corpus of literature has begun to consider this phenomenon and its influence upon the coaching process. This study adds to this literature by detailing the autoethnographic experiences of a case study coach; Derek. A contextualised and richly described narrative account of Derek’s experience of using coaching applications is provided. Analysis of Derek’s narrative suggests that technology can be a useful means by which individuals make sense of their experience. Specifically, (1) technology can be a ‘ready-to-hand’ instrument that enhances the coaching process. Unfortunately, (2) technology may become the only and ‘calculative’ means by which individuals come to understand their performance. In such instances, it is important to note that (3) the videos we use to understand our performance are transformed and incomplete representations of lived athletic experiences. Thus, Derek’s story illustrates how technology can be both an enabler and barrier to athletes who wish to holistically understand their own lived experiences and engage in coach-athlete relationships. The accompanying analysis draws upon concepts from Heideggerian philosophy to add insight into the use of technology within the coaching process. In so doing, the study prompts coaches to critically view their coach-athlete relationships as situated in a wider world which contains, and can be mediated by, technology. In addition, Derek’s story (re)directs researchers and coaching practitioners interested in technology to a useful literature (philosophy of technology) which may further inform their understanding of coach-athlete relationships.  相似文献   
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Previous research has highlighted the positive effect that different warm-up protocols have on golf performance (e.g. Sorbie et al., 2016; Tilley & Macfarlane, 2012) with the design of warm-ups and programmes targeting and improving golf performance through the activation and development of specific muscle groups. This study aimed to examine the acute effects of two warm-up protocols on golf drive performance in comparison to a control condition. Using a randomised counterbalanced design over three testing sessions, twenty-three highly skilled golfers completed the control, dynamic and resistance-band warm-up conditions. Following each condition, a GC2 launch monitor was used to record ball velocity and other launch parameters of ten shots hit with the participants’ own driver. A repeated-measures ANOVA found significant increases in ball velocity (ηp2 = .217) between the control and both the dynamic and resistance-band warm-up conditions but no difference between these latter two, and a reduction in launch angle between control and dynamic conditions. The use of either a dynamic stretching or resistance-band warm-up can have acute benefits on ball velocity but golfers should liaise with a PGA Professional golf coach to effectively integrate this into their golf driving performance.  相似文献   
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