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31.
The purpose of this study was to compare the validity and reliability of three short physical activity self-report instruments to determine their potential for use with university student populations. The participants (N = 155; 44.5% male; 22.9 ± 5.13 years) wore an accelerometer for 9 consecutive days and completed a single-item measure, the a brief two item measure and the International Physical Activity Questionnaire—Short Form questionnaires on day 1 and 9. Correlations between self-reported and accelerometer derived moderate-to-vigorous physical activity levels were moderate for the International Physical Activity Questionnaire—Short Form, while poor for the single-item measure and the a brief two item measure. The agreement level was high with the International Physical Activity Questionnaire—Short Form (77.4%) and moderate for both the single-item measure (45.2 %) and a brief two item measure (44.5 %). The intraclass correlations between the two administrations were moderate to strong across all measures (0.52–0.70) in 133 participants. The International Physical Activity Questionnaire—Short Form is the most suitable of these three self-report instruments for use with this population due to higher correlations and levels of agreement with accelerometry.  相似文献   
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Previous work has presented both a theoretical foundation for designing terrain park jumps that control landing impact and computer software to accomplish this task. US ski resorts have been reluctant to adopt this more engineered approach to jump design, in part due to questions of feasibility. The present study demonstrates this feasibility. It describes the design, construction, measurement, and experimental testing of such a jump. It improves on the previous efforts with more complete instrumentation, a larger range of jump distances, and a new method for combining jumper- and board-mounted accelerometer data to estimate equivalent fall height, a measure of impact severity. It unequivocally demonstrates the efficacy of the engineering design approach, namely that it is possible and practical to design and build free style terrain park jumps with landing surface shapes that control for landing impact as predicted by the theory.  相似文献   
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The aim of the work is to set up a methodological approach to verify the effectiveness of the treatments of decayed waterlogged archaeological wood and to point out the proper thermo-hygrometric conditions for its preservation after treatment. The treatments were performed on wood samples of maritime pine (Pinus pinaster Aiton), oak (Quercus sp. caducifolia), elm (Ulmus cf. minor) and strawberry tree (Arbutus unedo L.), obtained from stems pertaining to the original vegetation found in the excavation site of the Ancient Ships in Pisa (Italy), and dated from seventh century BC to second century AD The utilised products were: Polyethylene Glycols (PEG) of various molecular weights, a Polypropylene Glycol (PPG 425), Trehalose (α-D-glucopyranosyl-α-D-glucopyranoside), and their mixtures, and also a Hydroxypropylcellulose (Klucel). The main objective to be pursued by the treatments was considered the stabilisation of the original size and shape of samples. The various steps of this approach were: the execution of a preliminary diagnostic survey on untreated samples; the characterisation of treatment solutions ‘as such’ to establish the property to be monitored during the treatment; the evaluation of the main physical characteristics of wood after the treatment were determined. Among the latter, the coefficient of dimensional stability during the exposure to a series of selected thermo-hygrometric conditions and the retention of consolidants after the treatment. These two measurements allowed the definition of the ‘efficacy of a treatment’, φT, a new parameter firstly utilised in this work. It measures the stabilisation capability of the percent unit of retained product, and its value permits to put in evidence the consolidants that stabilise wood with the lowest amount of product. Conversely, it was not possible to measure the Anti-Shrink Efficiency (ASE), one of the most utilised parameters for the evaluation of treatments, because of the serious distortions and fractures observed in all the heavily degraded untreated samples.  相似文献   
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Nicola Grove, speech/language therapist, and Sine McDougall, psychologist, from the Division of Psychiatry of Disability, Department of Mental Health Sciences, St. George's Hospital Medical School, London, explore use of Makaton signs in teacher-directed and free play settings by children with severe learning difficulties.  相似文献   
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The past decade has witnessed increased interest in the visual search behaviour of athletes. Little is known, however, about the relationship between anxiety and eye movements in sport performers or about the extent to which athletes' planned and actual visual search strategies correspond. To address these issues, we conducted two studies. In Study 1, eight expert female gymnasts were presented with three digital slides of a model performing a skill that is known to be anxiety-provoking in this sport--namely, the 'back flip' on the beam. By varying the height of the beam and the presence or absence of safety mats, the slides differed in the amount of anxiety that they elicited vicariously in the viewer. In the study, the gymnasts were asked to imagine themselves in the position of the depicted model and to describe the anxiety that they felt. As they viewed the slides, their eye movements were recorded. As predicted, anxiety was associated with an increase in the number of fixations to peripheral areas. In addition, the more 'threatening' slides elicited significantly more fixations than the less feared images. In Study 2, the plans of 15 equestrian performers (5 expert, 5 intermediate and 5 novice) were elicited as they engaged in a virtual 'walk' around a computerized show-jumping course. Contrary to expectations, the congruence between intended and actual search behaviour was not significantly greater for expert riders than for the less skilled groups. Also, the fact that the top riders allocated more fixations to slides than the less skilled performers challenged the prediction that expertise would be associated with economy of visual search. Finally, as expected, the expert riders were significantly less dependent on the overall 'course plan' than the intermediate and novice equestrian performers when inspecting the fences.  相似文献   
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Using three stratified random samples of thirty-two teachers each from grades 2 through 5, a 3-group posttest-only control group research design was employed to determine the effectiveness of an in-service program utilizing simulation techniques on teacher awareness of pupils’ instructional reading levels. Pupils were selected randomly from each teacher’s classroom. Differences between the grade level of pupils’ readers and their performance on McCracken’s Standard Reading Inventory constituted the measure of teacher awareness. The importance of teachers’ grade level assignments and the time of year when this in-service training is conducted were also evaluated.

Findings indicated that this in-service program is effective only when conducted before school begins. There was a significant difference in teacher awareness among grade levels but a contravertible one between primary and intermediate levels.  相似文献   
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