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101.
Alan M. Nevill Yassine Negra Tony D. Myers Senda Sammoud Helmi Chaabene 《Journal of sports sciences》2020,38(7):787-794
ABSTRACTThis study identified key somatic and demographic characteristics that benefit all swimmers and, at the same time, identified further characteristics that benefit only specific swimming strokes. Three hundred sixty-three competitive-level swimmers (male [n = 202]; female [n = 161]) participated in the study. We adopted a multiplicative, allometric regression model to identify the key characteristics associated with 100 m swimming speeds (controlling for age). The model was refined using backward elimination. Characteristics that benefited some but not all strokes were identified by introducing stroke-by-predictor variable interactions. The regression analysis revealed 7 “common” characteristics that benefited all swimmers suggesting that all swimmers benefit from having less body fat, broad shoulders and hips, a greater arm span (but shorter lower arms) and greater forearm girths with smaller relaxed arm girths. The 4 stroke-specific characteristics reveal that backstroke swimmers benefit from longer backs, a finding that can be likened to boats with longer hulls also travel faster through the water. Other stroke-by-predictor variable interactions (taken together) identified that butterfly swimmers are characterized by greater muscularity in the lower legs. These results highlight the importance of considering somatic and demographic characteristics of young swimmers for talent identification purposes (i.e., to ensure that swimmers realize their most appropriate strokes). 相似文献
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Jennifer Ward Stephanie Branson Megan D. Cross Ilene R. Berson 《Journal of Research on Technology in Education》2016,48(3):227-238
This study explored how developmentally appropriate practices influenced the affordances of a multitouch surface in an early childhood classroom. Children, ages 4 to 5 years old, were videotaped while engaged in a storymaking application on a multitouch table. As a result of the study, we found that some challenges with the functionality undermined children's autonomous control. The researchers observed numerous instances of issues with control of the medium, including height of the table, sensitivity to multiple types of touch, and limited instructions and prompts. Implications for future research and practice are discussed. 相似文献
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Katherine D. Veazey Morris Gilbert R. Parra Sarah R. S. Stender 《Journal of College Counseling》2011,14(1):21-33
The authors assessed the influences of several risk factors—self‐esteem, history of unwanted sexual contact (USC), depression, and sorority membership—on eating‐related and weight‐related attitudes and behaviors. Findings provide support for the roles of self‐esteem, depression, and USC on restricting attitudes. According to the authors' model, these independent variables predicted restricting attitudes that then predicted restricting behaviors. Implications for preventive interventions and the study's limitations are discussed. 相似文献
108.
Chi (1992, 1993) Chi et al. (1994) suggests that many of the difficulties encountered by students in learning Physics concepts arise because they attribute the ontology of material substances to these concepts. These concepts are actually a special type of process - 'Constraint-Based Interactions' (CBI). Slotta and Chi (1996) reported on a study where a group of students explicitly trained in the CBI ontology showed significant gains over a control group in problem solving performance in eight simple electric circuit problems. This paper reports on a series of four studies which explore the usefulness of the ontological categorization framework in investigating students' alternative conceptions of electric circuits and in developing a teaching strategy for promoting conceptual change in the learning of basic electric circuitry concepts. 相似文献
109.
Attention disorders in the school population include attention deficit, hyperactivity and conduct disorders. A key concept for distinguishing hyperactive from attention disorders is behavioural inhibition as advocated by Barkley, a prominent American researcher. However, the concept itself needs to be understood because, as argued in this paper, there are two kinds of inhibition: Pavlov's original concept and the American one. These should be differentiated if the abnormal conditions associated with attention and hyperactivity are to be rationally connected to cognitive characteristics, rather than to be solely based on clinical symptoms and behavioural ratings. We suggest a consensus on the concept of inhibition and a unified view of attention disorders integrating cognitive and behavioural manifestations. Finally, the importance of basing remediation on a theoretically supported and rationally derived set of cognitive training tasks for the amelioration of inattention and hyperactivity is offered. 相似文献
110.
Kenneth D. Smith John Paul Eddy Thomas C. Richards Paul N. Dixon 《The American journal of distance education》2013,27(2):5-13
Abstract An empirical examination of accredited American higher education institutions was conducted to obtain baseline data regarding distance education copyright, intellectual property, and antitrust concerns. Additionally, a multiple‐case study involving ten of the top thirty accredited distance education institutions in America was conducted. Policy approaches were examined for all institutions, and differences were discussed between public and private institutions as well as between the following Carnegie Classification institutions: Research I and II, Doctorate I and II, and Master's I and II. Data indicated that, out of the schools surveyed, 22% of the institutions in these Carnegie Classification categories published copyright and intellectual property policies on their institution's Web site. In the case study, it was found that 90% of the institutions centrally controlled their distance education program administration as well as the copyright and intellectual property policies related to it. 相似文献