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61.
Valerie Carson Kylie D. Hesketh Ryan E. Rhodes Christina Rinaldi Wendy Rodgers John C. Spence 《Measurement in physical education and exercise science》2017,21(4):190-200
This study examined the psychometric properties of a questionnaire developed with the guidance of the socialization model of child behaviour to understand modifiable correlates of toddlers’ physical activity and sedentary behaviour. Findings are based on 118 parents (33.7 ± 4.9 years; 86% female) of toddlers (19.3 ± 2.7 months; 48% female) from Edmonton, Canada in The Parents’ Role in Establishing healthy Physical activity and Sedentary behaviour habits study (PREPS). The PREPS questionnaire encompassed 21 variables across the constructs of the socialization model of child behaviour. Of the nine variables assessed for internal consistency reliability, eight had good (α ≥ 0.70) reliability. Of the 15 continuous variables assessed for 1-week test–retest reliability, 10 had moderate (intra-class correlation = 0.50–0.74) and 5 had good (intra-class correlation ≥ 0.75) reliability. Of the six categorical variables assessed for 1-week test–retest reliability, two had fair (К = 0.21–0.40), one had moderate (К = 0.41–0.60), one had substantial (К = 0.61–0.80), and two had almost perfect (К = 0.81–1.00) reliability. Of the 12 sedentary behaviour variables assessed for convergent validity, 7 were significantly correlated with children’s screen time, of which three were small (r ≤ 0.29), two were medium (r = 0.30–0.49), and two were large (r ≥ 0.50) effect sizes. 相似文献
62.
Julia D. Plummer Valerie M. Zahm Rebecca Rice 《Journal of Science Teacher Education》2010,21(4):471-493
This study investigated the impact of an open inquiry experience on elementary science methods students’ understanding of
celestial motion as well as the methods developed by students to answer their own research questions. Pre/post interviews
and assessments were used to measure change in participants’ understanding (N = 18). A qualitative approach was used to describe the nature of each participant’s investigation through an analysis of
their science journal and poster presentations. A comparison of participants’ inquiry projects with the change in their understanding
revealed that while most participants improved in both their area of inquiry and beyond, elementary science methods students
may need more guidance to reach a full scientific understanding across all aspects of celestial motion. 相似文献
63.
The main purpose of the present research was to check the possibility of measuring the feeling of “intuitive acceptance”, experienced by a subject when he offers an intuitive solution to a problem. It was postulated that two dimensions have to be considered and combined: The level of confidence and the degree of obviousness. Almost all the questions asked referred to the notion of infinity. The subjects were pupils belonging to grades 8 and 9. Three main categories of problematic situations have been identified:
- Problems which got high percentages of correct solutions and high levels of intuitive acceptance.
- Problems which got two types of contradictory solutions, each of them being accepted with moderate intuitiveness.
- Problems which got low frequencies of correct solutions and high frequencies of typical incorrect solutions, the second category presenting higher levels of intuitive acceptance than the first (counter-intuitive problematic situations).
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65.
Debra A. Felix Mark D. Hertle Jill G. Conley Lori B. Washington Peter J. Bruns 《CBE life sciences education》2004,3(3):189-195
We describe an assessment of the collective impact of 35 grants that the Howard Hughes Medical Institute (HHMI) made to biomedical research institutions in 1999 to support precollege science education outreach programs. Data collected from funded institutions were compared with data from a control group of institutions that had advanced to the last stage of review but had not been funded. The survey instrument and the results reveal outcomes and impacts that HHMI considers relevant for these programs. The following attributes are considered: ability to secure additional, non-HHMI funding; institution buy-in as measured by gains in dedicated space and staff; enhancement of the program director''s career; number and adoption of educational products developed; number of related publications and awards; percentage of programs for which teachers received course credit; increase in science content knowledge; and increase in student motivation to study science. 相似文献
66.
To elucidate a higher rate of premature cardiovascular disease (CVD) in Asian Indian descendants (Roma) in Slovakia, we investigated frequency distribution, correlates and relationship of lipoprotein(a) [Lp(a)] to family CVD risk factors in Roma children and their Caucasian neighbors. The study sample consisted of 607 healthy children aged 7–18 years (55% Roma, 48% male) as part of the biracial (Roma–Caucasian) Slovak Lipid Community Study. Overall, frequency distribution data of Lp(a) were highly skewed to low concentrations, with markedly higher Lp(a) levels in Roma than in Caucasian children (median and range, mg/dL: 14.5; 0–159.2 vs 6.2; 0–112.3, P < 0.001), regardless of age and gender. Lp(a) was positively correlated with apo B (0.159, P = 0.004) in Roma, and LDL cholesterol (0.170, P = 0.005) in Caucasian children. In addition, daily income of the family was negatively related with Lp(a) in Roma (−0.134, P = 0.036) while positively in Caucasians (0.136, P = 0.047). For both race groups, no significant association was found between Lp(a) and age, body mass index, mean arterial pressure, smoking, and physical activity. Also, no significant relationships were examined between serum Lp(a) levels >30 mg/dL in children and family CVD risk factors, except for diabetes mellitus in parents of Caucasian origin (OR 4.46; 95%CI: 1.23–16.20). In a multivariate analysis, daily income, LDL cholesterol or apo B explained ~7% of the variance of Lp(a). This study suggests a significantly higher serum Lp(a) levels in Roma than in Caucasian children and a small effect, in general, of relevant CVD risk factors on the variation of Lp(a) levels in childhood. 相似文献
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70.
The aim of this study was to develop an exercise protocol to simulate tennis matchplay on a 'category 2' surface. Match analyses were used to form the basis for the design of the protocol. The protocol involved playing against a tennis ball serving machine. Part A of the protocol comprised 92 min 46 s of simulated tennis matchplay; Part B consisted of continuous hitting to the point of 'volitional fatigue' or when the required hitting frequency for two consecutive ball feeds could no longer be maintained. Ten elite tennis players (5 males, 5 females) volunteered to participate in the study, which was performed on an indoor tennis court (Matchplay, En-Tout-Cas). Their age, body mass and estimated maximal oxygen uptake were as follows: males, 21.7 +/- 1.0 years, 73.6 +/- 2.6 kg and 58.0 +/- 1.7 ml x kg(-1) x min(-1), respectively; females, 21.9 +/- 1.3 years, 62.3 +/- 2.0 kg and 42.2 +/- 0.7 ml x kg x min(-1), respectively (mean +/- sx). Heart rate, change in body mass and time to volitional fatigue were monitored. The heart rate responses of the participants to the simulated matchplay (range: 140-157 beats x min(-1), 73-81% peak heart rate) were consistent with the results of previous studies, for 'actual' matchplay. This protocol was successful in simulating similar physiological responses in Part A to 'actual' matchplay on a 'category 2' surface, in a controlled environment; it was also a sensitive evaluation tool of skilled performance in Part B. The current protocol may be used as a baseline protocol for studying the influence of, for example, training and dietary intervention on performance. 相似文献