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31.
Abstract

Body composition is a key consideration in the physical make-up of professional soccer players. The aims of the present study were to determine whether the body composition of professional soccer players varied according to playing position, international status or ethnicity, and to establish which variables best distinguished the soccer players from a reference group. Body composition was assessed using dual-energy X-ray absorptiometry in 64 male professional soccer players. Measured variables included bone mineral density and the relative amounts of lean and fat mass. Data were analysed using analysis of variance and stepwise discriminant function. The soccer players recorded better values than a reference group (n = 24) for all body composition compartments. Percent lean mass and bone mineral density were the variables best able to identify the soccer players (95.5% correctly classified). Differences in body composition were evident between goalkeepers and outfield players, but not between outfield playing positions. No differences were found on the basis of international status. The non-Caucasian players demonstrated significantly lower percent body fat (9.2 ± 2.0%) than the Caucasian players (10.7 ± 1.8%). It was concluded that body composition is important for elite soccer players, but that homogeneity between players at top professional clubs results in little variation between individuals.  相似文献   
32.
Abstract

Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention of or recovery from hip adductor strains. Large, eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography (EMG) of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut manoeuvres in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all P < 0.042). From this preliminary analysis, wearing directional compression shorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts.  相似文献   
33.
This article uses data from the PIAAC (Programme for the International Assessment of Adult Competences) Background Questionnaire to describe conditions related to informal learning (IL) in the workplace and opportunities to learn informally in organizations in Spain. PIAAC data indicate that in Spain, informal learning processes in organizations are a common, everyday practice. However, some differences have been found in the intensity of this learning by gender, the position that the employee occupies and the business sector in which the organization is framed. This study opens some future avenues to develop further knowledge about IL mechanisms and practices in the workplace, as a strategy to help towards the development of people and organizations.  相似文献   
34.
Objective. Parenting behavior is presumed to be related to the thoughts about child behavior that parents report in a controlled and explicit manner and to more implicit parent cognitions that occur outside of conscious awareness and are less accessible to verbal report. Design. We examined mothers’ attitudes toward their children as correlates of self-reported parenting behavior. We used a combination of a self-report questionnaire and a reaction-time method (the Implicit Association Test) to assess explicit and implicit attitudes, respectively. We also assessed mothers’ implicit and explicit attributions for child misbehavior in relation to parenting, using a questionnaire measure of attributions completed under high-cognitive load (implicit attributions) or under low-cognitive load (explicit attributions). Mothers of 124, 6- to 10-year-olds (52% male) participated. Results. Attitudes assessed by self-report questionnaire and the Implicit Association Test were uniquely associated with negative parenting. The cognitive load manipulation moderated associations between attributions and parenting, such that child-blaming attributions were inversely associated with positive parenting only under conditions of high-cognitive load. Conclusions. Compared to traditional self-report questionnaires, methods such as the Implicit Association Test or cognitive load manipulations may more effectively assess implicit parent cognitions.  相似文献   
35.
Texts     
Made in America: Immigrant Students in Our Public Schools. Laurie Olsen, New York: The New Press, 1997, 276 pages, $25.00 (hardcover), ISBN 1–5658–4400–9, and $14.95 (softcover), ISBN 1–5658–4471–8.

The Power of Their Ideas: Lessons for America From a Small School in Harlem. Deborah Meier, Boston: Beacon Press, 1995, 190 pages, $12.00 (softcover). ISBN 0–8070–3111–9.

Yesterday, Today & Tomorrow: Meeting the Challenge of Our Multicultural America & Beyond. Paul D. Christiansen and Michelle Young, San Francisco: Gaddo Gap Press, 1996, 376 pages, $29.95 (softcover). ISBN 1–8801–9218–7.  相似文献   
36.
37.
The present study explored the relationship between the intelligence of young adults and their performance on the Test of Variables of Attention (TOVA). The study also examined whether significant differences existed between adults with and without attention-deficit/ hyperactivity disorder (ADHD) on TOVA errors of omission, errors of commission, mean correct response time, and variability, as well as on performance on the freedom from distractibility (FD) factor on the Wechsler Adult Intelligence Scale-Revised (WAIS-R). Seventy-nine adults participated in the study, including 17 with ADHD and 62 college students without ADHD. Pearson product-moment correlations indicated that none of the correlations between Full Scale IQ (FSIQ) and TOVA variables were significant. Analysis of variance results revealed that adults with ADHD made more errors of omission on the TOVA than did controls. Between-group differences were not found on the remaining dependent variables.  相似文献   
38.
Early years curricula promote learning through play and in addition emphasise the development of computer literacy. Previous research, however, has described that teachers feel unprepared to integrate Information and Communication Technology (ICT) and play. Also, whereas research has suggested that effective computer use in the early years is associated with adult direction, further research suggests adult presence can inhibit play and reduce children's engagement. Focusing on 12 settings following the Welsh play-based Foundation Phase, this paper explores teachers' experiences of integrating computer use into classroom practice, children's levels of engagement with computer activities and how playful children perceive computer use to be. Teachers confidently delivered a variety of computing experiences. Children consistently rated these activities as play regardless of adult presence and demonstrated moderate to high levels of engagement. Findings and the features of observed practice are discussed in relation to the teachers' role as a play partner and the successful co-construction of the play-based curriculum.  相似文献   
39.
This study investigated the impact of different aspects of the circle of friends (CoF) intervention. A naturalistic sample of 14 primary‐aged children with a range of special educational needs were involved, seven of whom were followed‐up a term later, to assess medium‐term impact. The whole‐class meeting was found to be effective in increasing the social inclusion of the focus children. However, with the exception of one child with an autistic spectrum disorder (ASD), the weekly CoF meetings produced no measurable further improvements. Possible explanations for the pattern of findings and implications for educational psychology practice are discussed.  相似文献   
40.
本文初步对保山市反季节蔬菜进行分析,纵向从蔬菜种子的来源、蔬菜的栽培、蔬菜的收集销售、贮藏和运输这一商品链出发,逐级分析菜农、蔬菜收集人、菜老板的收益分析,从而在整体上揭示菜农在这条商品链上的收益地位;横向同种植其他经济作物,如香烟和甘蔗的收益作对比分析。说明了西部民族山区的广大农户主要收入来源于种植业的现实,农户如何选择种植的经济作物对提高收入有直接的影响,决定农户种植收益除了市场的因素以外各级政府的行政行为则也起到一定的作用。  相似文献   
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