Information-governing dynamics of attacker-defender interactions in youth rugby union

Previous work on dynamics of interpersonal interactions in 1 vs. 1 sub-phases of basketball has identified changes in interpersonal distance between an attacker and defender as a potential control parameter for influencing organizational states of attacker-defender dyads. Other studies have reported the constraining effect of relative velocity between an attacker and defender in 1 vs. 1 dyads. To evaluate the relationship between these candidate control parameters, we compared the impact of both interpersonal distance and relative velocity on the pattern-forming dynamics of attacker-defender dyads in the sport of rugby union. Results revealed that when interpersonal distance achieved a critical value of less than 4 m, and relative velocity values increased or were maintained above 1 m x s(-1), a successful outcome (i.e. clean attempt) for an attacker was predicted. Alternatively, when values of relative velocity suddenly decreased below this threshold, at the same critical value of interpersonal distance, a successful outcome for the defender was predicted. Data demonstrated how the coupling of these two potential, nested control parameters moved the dyadic system to phase transitions, characterized as a try or a tackle. Observations suggested that relative velocity increased its influence on the organization of attacker-defender dyads in rugby union over time as spatial proximity to the try line increased.     

Are parental concerns about children's inactivity warranted, and are they associated with a supportive home environment?

This paper explores parental concern about children's activity levels and whether parents who are concerned about their child's activity provide a supportive environment. A sample of 615 parents of 5-6-year-old children and 947 parents of 10-12-year-old children completed a questionnaire. Just over 50% of parents reported they were concerned their child was not getting enough activity. Children of concerned parents were less active than those whose parents were not concerned. These findings suggest that parents who are concerned about their child's physical activity levels provided a less supportive environment for physical activity than parents who are not concerned. The challenge for public health will be to harness parental concerns and translate them into action.     

A definition of dyslexia

This paper elaborates on the components of a working definition of developmental dyslexia. It follows the general format of a paper by Lyon published in Annals of Dyslexia in 1995, which elaborated on a working definition proposed in 1994 (Lyon, 1995). The current definition agreed on by the work group updates and expands on the working definition from 1994.     

Relationship between toy and material use and the occurrence of social interactive behaviors by normally developing preschool children

The purpose of this naturalistic study was to identify the kinds of social behaviors that normally developing preschool children exhibit while manipulating various toys and materials found in most preschool settings. One hundred fifteen 3-, 4-, and 5-year-olds in four day-care centers were observed during free play periods. Thirty-eight available toys and play materials were rated as to whether they were used in an Isolate, Parallel, Sharing/Cooperative, or Physical Assistance context. The resulting data on toy/material use are discussed in terms of selecting physical stimuli in social behavior modification efforts that clearly set the occasion for positive social interaction.     

The activity context of preschool children's social interactions: A comparison of high and low social interactors

The purpose of this observational study of the activity context in which preschool children engaged in positive social interactions was to produce a data source that could be used to assist in the identification of socially withdrawn children, and to select efficient training contexts in which to develop the social behavior repertoire of withdrawn youngsters. Eleven high-rate and 10 low-rate social interactors, ranging in age from 36 to 72 months, were observed for 12 10-minute sessions across a 3-month period. Six activity contexts were coded by trained observers: Observer, Isolate, Parallel, Game, Cooperative, and Fantasy. The results indicated that: (a) Low-rate children engaged in significantly more Isolate and Observer activity than did high-rate children. (b) High-rate children engaged in significantly more Cooperative and Fantasy activity than did low-rate children. (c) There were no significant differences between groups for Game and Parallel activities. Results are discussed in terms of the concurrent validity between frequency of interaction measures and the activity context data, the developmental progression of social skills acquisition, and the selection of treatment contexts for withdrawn children.     

高中学生自我锻炼能力培养的实践探索

随着素质教育和《全民健身计划纲要》的实施，终身体育思想的树立，要求高中体育教育加强对学生体育意识和自我锻炼能力的培养。运用文献资料法、教学实验法，探索高中学生自我锻炼能力的培养。研究认为现阶段的高中体育教育，是完全能培养学生的体育意识和自我锻炼能力的，但应加强学校、家庭、社会的联系，让学校、家庭、社会互为补充，形成一体，共同促进学生体育锻炼意识和自我锻炼能力的提高。