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ABSTRACT

In this study, the electronic and optical properties of wurtzite MgxZn1−xO structures for different Mg mole fractions (x) are studied using Density Functional Theory (DFT). In calculations, the generalised gradient approximation (GGA + U) formalism is used with the Hubbard parameters (U) are applied to Zn-3d and O-2p electrons of ZnO. The calculated electronic band structures show that the band gap energies of the investigated structures increase linearly with increasing Mg mole fraction from 0 to 31.25% which is also quantitatively consistent with the previous experimental results. In addition, the electron effective masses of investigated MgxZn1−xO structures are calculated. The electron effective masses of investigated structures show an increment linearly with increasing Mg mole fractions. The optical results show that the absorption edges of the structures move toward the higher energies region as the Mg mole fractions increase.  相似文献   
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The concept of an embodied career draws attention to the individual, corporally, socially, culturally and institutionally located in relationship with work. Career theories have tended to focus on psychological and social variables and measurements that narrow understanding of contexts and agency. It is thus timely to consider a more holistic approach to understanding contemporary careers as embodied processes. The paper works on three levels; first as an empirical illustration of professional sports careers as short-term careers, second as an application of Bourdieu's habitus to understand the relationship between social fields and accounts of career choice and, third in order to draw parallels with the embodied nature of work in a more general sense. Utilising empirical material from a study of elite UK professional rugby players, it is argued that understanding an embodied-career resonates with present concerns regarding career patterns of short-term contracts, which require the individual to be committed, flexible and adaptable, be prepared for exit, and yet remain immersed and dedicated to the current sphere of employment. It is proposed that this kind of immersion requires alternatives to be, temporarily at least, silenced and in this context renders the accrual of bodily capital as fit, but only temporarily fit for purpose.  相似文献   
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ObjectivesGrounded in personal and social identity theory, the purpose of this study was to examine whether parents’ personal and social identity perceptions influence their moral intentions towards antisocial parent behaviour in a youth sport setting.DesignParents of competitive youth ice hockey players (N = 437) read a vignette that either described a parent from the participant’s own team (i.e., ingroup), or a parent from an opposing team (i.e., outgroup) acting antisocially towards an athlete from the participant’s own team, an opposing athlete, or their own child. Parents were asked whether they would respond to the antisocial behaviour in the form of direct or indirect criticism or report the behaviour to the coach or to the league.ResultsParents were more likely to directly criticize ingroup parents than outgroup parents and they were more likely to indirectly criticize outgroup parents than ingroup parents. Further, parents with stronger social identities reported higher intentions to indirectly criticize an outgroup parent. There were no main effects for reporting behaviour (to coach or league), and personal identity did not moderate relationships with moral intentions towards antisocial behaviour.ConclusionBy providing parents with a situation that includes antisocial parent behaviour in the immediate youth sport environment, novel insight was gathered with regard to what contextual elements might drive parents’ intention to criticize, but not report antisocial behaviour.  相似文献   
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Adolescent athletes report body image concerns that negatively impact their sport experiences and participation. The coach’s perspective may be informative to how the context of sport perpetuates, supports, or protects from negative body image. Yet few coaches are represented in this area of research. The purpose of the present study was to explore coaches’ perceptions of body image in girls sport. Thirteen coaches with an average of 10 years of experience working with girls in primarily non-aesthetic team sports were interviewed. Based on inductive thematic analysis, coaches’ perceptions of the athletes’ body image concerns were reflected in four themes labelled (i) body image: the ‘elephant’ on the field (i.e., identifying the unspoken nature of body image), (ii) agents of body image in sport (i.e., parents, coaches, and media), (iii) skill over appearance (i.e., focusing on athletic skill and competence), and (vi) systemic strategies. This last theme offers several considerations for improving the sport context with a lens to improve body image. Of relevance, it was apparent that all coaches operationalized body image as predicated on appearance, body shape, and weight and this narrow simplistic perception could guide future programs and practices. Taken together, findings highlight the need to intervene with coaches to provide adequate support and education on body image in girls sport.  相似文献   
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Beginning from an earlier claim of mine that there was really no such area of study as the philosophy of sport, Part One of the paper reconsiders the place previously given to David Best’s distinction between purposive sports and aesthetic sports. In light of a famous cricketing event in the 1977 contest between England and Australia (‘The Ashes’), in which Derek Randall turned a cartwheel after taking the winning catch, the paper clarifies that not all aesthetically-pleasing events taking place in sporting competitions can be understood as the aesthetic in sport. Then, in Part Two, the force of the claim that philosophy is one subject is explored. The conclusion is that a focus just on the philosophy of sport is necessarily inappropriate, since it will present the student with only cases from sport to then apply to sport. Rather, one’s understanding must be informed by (much of) the breadth of philosophy. Charles Travis’s view of occasion-sensitivity provides a clear example of appropriately contextual appeal. Part Three of the paper returns to the need for an institutional account of sport, one recognizing that there is no one occasion on which a particular sport is played; and hence no single set of conditions which can uniquely identify that sport. Thus, soccer played with one’s children typically differs from elite soccer: but both are (genuinely) soccer. When one turns to the appreciation of sport (in the light of Stephen Mumford’s excellent Watching Sport: Aesthetics, Ethics and Emotion [2012a]), one recognizes that, in order to genuinely appreciate sport, one cannot detach oneself from the outcome as completely as Mumford’s extreme purist seems to. But reflection on that case may also return us to contextualism by moving us away from attachments to the complete or the exceptionless in our accounts of spectating as of sport: maybe there is no one thing that occurs in all the relevant cases.  相似文献   
8.
The purpose of the current research was to (a) develop and establish the factor structure of the Czech and Slovak versions of the Youth Sport Environment Questionnaire (YSEQ; Eys, Loughead, Bray, & Carron, 2009) and (b) examine the relationship between team performance and cohesion with a sample of European elite youth sport teams. At time point one, with 352 elite youth athletes from 22 teams, support was obtained for a two factor structure underlying the YSEQ. Based on data collected at the second (N = 291) and third (N = 246) time points, multilevel analyses revealed that, when controlling for midseason cohesion, midseason team performance significantly and positively predicted task and social cohesion later in the season. Neither task nor social cohesion predicted team performance. In addition to adapting the YSEQ for use in a unique context, these findings reveal the nature of the cohesion-performance relationship in elite youth sport.  相似文献   
9.
Abstract

Mental preparation, or “psych-up” strategies have been assumed to promote physical arousal which subsequently improves certain athletic performances. The present experiment examined the role of arousal changes in the use of psych-up strategies on a physical strength task and a reaction time-decision task for subjects varying in competitive experience. Eighty-four subjects were reliably divided into high, moderate, or low competitive experience groups and randomly assigned to one of three mental preparation strategies. These strageies, which the subjects employed during a mental preparation period for both tasks, were either: (a) a self-generated arousal strategy, (b) a prescribed arousal strategy, or (c) a placebo-control strategy. While heart rate was being monitored, each subject completed a baseline trial, then one trial following a 45 sec mental preparation period and one trial following a 45 sec distraction interval. Order of presentation of tasks and order of presentation of distraction and mental preparation trials were counterbalanced and statistically analyzed. The results support the utility of different mental preparation strategies for increasing strength performance, but not reaction time-decision performance, for subjects with moderate and high levels of previous competitive experience. Self-generated arousal strategies enhanced performance of moderate experienced subjects. Analyses of the heart rate data failed to support the assumption that physiological arousal mediates the influence of psych-up strategies. Mental preparation strategies improved athletes' performance on certain tasks, however these strategies do not necessarily achieve their effects through increased autonomic arousal.  相似文献   
10.
ObjectivesTo evaluate sport burnout research using citation network analysis.DesignA citation network analysis.MethodsWe began by searching the term “sport and burnout” in SportDiscus, Physical Education Index, and PsycINFO. From the returned search, we then selected and analyzed all peer-reviewed English articles that were published before 2012. This allowed us to create a network of inter-citations.ResultsOur search yielded 102 articles, of which there were 11 reviews (11%), 13 qualitative articles (13%), 76 quantitative articles (75%), and two mixed methods (qualitative and quantitative) articles (2%). The 11 most cited articles were published between 1984 and 2006, appearing in 5 journals (7 of them in the same journal). Merely 2 of the most cited articles investigated coach burnout. Top-cited articles typically conducted original research using male and female individual sport athletes and were published by North American authors, with two recent exceptions. The most cited article, and also most influential burnout model, was Smith's (1986) cognitive-affective stress model.ConclusionsThe findings show that following an initial focus on coach burnout, more recent studies examine athletes. In this paper we have identified some strengths amongst the most cited papers, including a wide range of publication dates and a focus on both male and female athletes; however, there were also limitations such as a scarcity of articles investigating team sport athletes.  相似文献   
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