Quantifying physical activity in first-through fourth-grade physical education via pedometry

The aim of this study was to determine pedometry steps per minute (SPM) cutscores that accurately quantify physical activity (PA) time in first- through fourth-grade physical education. A total of 257 participants were grouped in two data pools, first- and second-grade (n = 126), and third- and fourth-grade (n = 131). Systematic observation was the PA criterion instrument and pedometry was the predictor instrument. Correlations between physical activity measures were strong (r = .82-.89, p < .01). Ten min of PA and 33.33% of the lesson time engaged in PA within a 30-min class can be quantified by 61-63 SPM for first- and second-grade, and 58-61 SPM for third- and fourth-grade. IN CONCOLUSION: (a) SPM values were a valid indicator of students achieving or not achieving PA criteria, and (b) pedometry is a valid and practical tool for physical activity surveillance within physical education.     

Anticipating ethical issues in emerging IT

In this essay, a new approach to the ethics of emerging information technology will be presented, called anticipatory technology ethics (ATE). The ethics of emerging technology is the study of ethical issues at the R&D and introduction stage of technology development through anticipation of possible future devices, applications, and social consequences. In the essay, I will first locate emerging technology in the technology development cycle, after which I will consider ethical approaches to emerging technologies, as well as obstacles in developing such approaches. I will argue that any sound approach must centrally include futures studies of technology. I then present ATE and some applications of it to emerging information technologies. In ATE, ethical analysis is performed at three levels, the technology, artifact and application levels, and at each levels distinct types of ethical questions are asked. ATE analyses result in the identification and evaluation of a broad range of ethical issues that can be anticipated in relation to an emerging information technology. This ethical analysis can then be used for ethical recommendations for design or governance.     

Comparison of power and EMG during 6-s all-out cycling between young and older women

Abstract To investigate the effects of ageing on the neural control strategies governing sprint cycling on a friction-loaded cycle-ergometer, 10 older (aged 70-83yr) and 8 young (aged 19-35yr) healthy women completed seven 6-s all-out cycling trials against varying loads. Root mean square (RMS), median frequency and muscle fibre conduction velocity were determined from the vastus lateralis of the dominant limb during each pedal stroke. Peak power was 43% lower in the older group compared to the younger (p??0.05). ΔRMS from the first to the sixth second during each trial was found to increase significantly with the development of power output in both groups (p?相似文献   

Preschool children's attention to environmental messages about groups: social categorization and the origins of intergroup bias

This study was designed to examine the effects of adults' labeling and use of social groups on preschool children's intergroup attitudes. Children (N=87, aged 3-5) attending day care were given measures of classification skill and self-esteem and assigned to membership in a novel ("red" or "blue") social group. In experimental classrooms, teachers used the color groups to label children and organize the classroom. In control classrooms, teachers ignored the color groups. After 3 weeks, children completed multiple measures of intergroup attitudes. Results indicated that children in both types of classrooms developed ingroup-biased attitudes. As expected, children in experimental classrooms showed greater ingroup bias on some measures than children in control classrooms.