Worldwide variation in the performance of children and adolescents: An analysis of 109 studies of the 20-m shuttle run test in 37 countries

Abstract

This study is a meta-analysis of 109 reports of the performance of children and adolescents on the 20-m shuttle run test (20-mSRT). The studies were performed in 37 countries and included data on 418,026 children, tested between 1981 and 2003. Results were expressed as running speed (km · h^?1) at the final completed stage of the 20-mSRT. Raw data were combined with pseudodata using Monte Carlo simulation. The 20-mSRT performances were expressed as z-scores relative to all children of the same age and sex from all countries. An overall “performance index” was derived for each country as the average of the age- and sex-specific z-scores for all children from that country. Factorial analysis of variance was used to compare scores among countries and regions, and between boys and girls of the same age. There was wide and significant (P < 0.0001) global variability in the performance of children. The best performing children were from the Northern European countries Estonia, Iceland, Lithuania, and Finland (0.6 – 0.9 standard deviations above the global average). The worst performing children were from Singapore, Brazil, USA, Italy, Portugal, and Greece (0.4 – 0.9 standard deviations below the global average). There is evidence that performance was negatively related to being overweight, as well as to a country's average temperature.     

Public policies towards Research Joint Venture: Institutional design and participants’ characteristics

In this paper, we present several insights regarding the influence of institutional design on the process of Research Joint Venture (RJV) formation. Our results are obtained with a firm-level dataset on RJVs formed under the umbrella of the Eureka initiative and of the European Union’s Framework Programmes (EU-FPs) for science and technology. We focus on firms that are known to have a high probability of forming RJVs, with the latter identified as firms with a past experience in collaborative research. The results indicate that EU-FP RJVs are consistent with a “top-down” and “mission oriented” research policy. By contrast, Eureka RJVs appear as more market driven and “bottom-up”.     

Discriminant analysis of anthropometric and biomotor variables among elite adolescent female athletes in four sports

The aim of this study was to identify anthropometric and biomotor variables that discriminated among groups of elite adolescent female athletes aged 14.3 +/- 1.3 years (mean +/- s) from four different sports (tennis, n = 15; swimming, n = 23; figure skating, n = 46; volleyball, n = 16). The anthropometric variables included body mass, height, bi-epicondylar breadth of the distal extremity of the humerus and femur, maximal girth of the calf and biceps and the sum of five adipose skinfolds. The biomotor variables were maximal aerobic power, muscular endurance and flexibility of the trunk. Discriminant analysis revealed three significant functions (P < 0. 05). The first discriminant function primarily represented differences between figure skaters and all other groups of athletes. The other two underlined anthropometric and biomotor differences between swimmers and volleyball players and between tennis players and swimmers, respectively. After validation, the analysis showed that 88% of the athletes were correctly classified in their respective sports. Our model confirms that elite adolescent female athletes show physical and biomotor differences that clearly distinguish them according to their particular sport.     

Are intensified physical education sessions able to elicit heart rate at a sufficient level to promote aerobic fitness in adolescents?

The purpose of this study was to determine the effects of intensified physical education sessions on adolescents ages 11-16 years. They were divided into two experimental groups--high-intensity running group (HIRG) and high-intensity jumping group (HlJG)--and a control group (C). During the sessions, heart rate (HR) was monitored. There was no significant difference between mean HR for HIRG and HIJG, while the mean HR was significantly lower for C (p < .001). For both HIRG and HIJG, the mean HR was significantly higher for girls than for boys (p < .001). Our results suggested that these intensified physical education lessons require a high percentage of maximal HR in adolescents and can be used to improve aerobic fitness.     

Effets du sport sur le comportement social de l'adolescent

Sans résumé     

Brain opiates

Morphine, which is obtained from poppies, has pharmacological properties which make it both a powerful pain-relieving drug and a narcotic feared for the dependency which it induces in those who use it. Study of the mode of action of morphine has revealed related endogenous substances in the brain. These brain opiates have remarkable properties, which researchers are just beginning to discover.     

Computing and the Teaching of Structural Analysis/ Le calcul par ordinateur et l'enseignement de l'analyse des structures

Computer structural analysis is now one of the fundamental pillars in the teaching of engineering. The task is to capitalize on all the new technologies in order primarily to help the students understand the behaviour of structures and, by the same token, improve their ability to analyze them. Consequently, the computer has to be exploited in a smart and ingenious way to achieve this task better. If, in the past, this was done in a more or less successful way, it is nowadays extremely difficult, if not quite impossible, to perform this task in a satisfactory manner. This is changing not only the teaching of structural analysis but also the content of the engineering courses. Hence, a reassessment and a reorganization of the teaching of computing for structural analysis have to take place. In this paper, a few ideas on the teaching of computing for structural analysis are discussed.     

Measuring the Interactive Skills of Caregivers in Child Care Centers: Development and Validation of the Caregiver Interaction Profile Scales

Research Findings: High-quality caregiver–child interactions constitute the core of high-quality child care for young children. This article describes the background and development of the Caregiver Interaction Profile (CIP) scales to rate 6 key skills of caregivers for interacting with 0- to 4-year-old children in child care centers: sensitive responsiveness, respect for autonomy, structuring and limit setting, verbal communication, developmental stimulation, and fostering positive peer interactions. Each interactive skill is rated on a 7-point scale based on observation of video-recorded caregiver–child interactions. Together, the 6 scale scores constitute an Interaction Profile for individual caregivers that may serve as a starting point for education and training to improve the quality of caregiver–child interactions. This article also presents the results of a 1st study with the CIP scales, in a sample of 145 caregivers from 75 child care groups in 47 child care centers in The Netherlands. Practice or Policy: Results provide promising preliminary evidence supporting the reliability and validity of the CIP scales.