Coordination variability and skill development in expert triple jumpers   总被引：1，自引：0，他引：1  

Wilson C  Simpson SE  van Emmerik RE  Hamill J 《Sports biomechanics / International Society of Biomechanics in Sports》2008,7(1):2-9

The aim of this study was to examine the influence of skill of expert triple jumpers on the coordination variability of lower extremity intra-limb couplings. In contrast to the traditional motor learning perspective, we hypothesized that as skill and thus performance increases, movement coordination variability will also increase. Three-dimensional kinematic and ground reaction force data were collected during the hop-step transition phase of the triple jump. Relative motion plots and a modified vector coding technique were used to quantify the coordination variability across the trials. The results were consistent with a U-shaped curve, representing coordination variability, as skill increases. The high coordination variability in less skilled athletes is present while the appropriate characteristics defining the movement coordination patterns are acquired. This coordination variability may not be beneficial to performance. As the refinement of these characteristics is achieved, coordination variability decreases, resulting in a more consistent or regulated performance. In the final stages of developing a skilled performance, a functional variability is accessed that brings flexibility to the system allowing it to cope with perturbations. This study highlights the need to address the learning effect when analysing coordination variability from a dynamical systems perspective.  相似文献   

Do physical activity beliefs differ by age and gender?   总被引：1，自引：0，他引：1  

Rhodes RE  Blanchard CM  Blacklock RE 《运动与训练心理学杂志》2008,30(3):412-423

Age and gender are consistently related to physical activity (PA), yet theoretical explanation for these associations is scant. The present study compared the mean values and correlations of a population sample, divided by gender and age group, with respect to theory of planned behavior beliefs (behavioral, normative, and control) and PA. Participants were a sample (N=6,739) of adults (M age=49.65, SD=16.04) who completed measures of social and health demographics, theory of planned behavior beliefs, and self-reported PA. Mean analyses identified greater perceived control over PA for seniors than for young and middle-aged adults (N>.025). Belief-behavior correlations, however, were not different across age and gender in 24 of 26 tests (q<.19). Thus, PA beliefs are invariant across age and gender with the exception of mean levels of perceived control, which are lower among younger adults than older adults. Factors such as early parenthood and career demands were considered the likely reasons for differences. Overall, the evidence suggests that adapting theoretical models for specific age groups or based on gender may not be necessary.  相似文献   

Extended Test Time and postsecondary Students with Learning Disabilities: A Model for Decision Making     

Nicole S. Ofiesh  Charles Hughes  Sally S. Scott 《Learning disabilities research & practice》2004,19(1):57-70

The most frequently requested accommodation among students with learning disabilities (LD) in postsecondary settings is extended test time. The frequency with which this accommodation is requested and granted compels disability service providers to become knowledgeable about the factors that influence the need for, and appropriateness of, the accommodation. Moreover, the synthesis of these factors becomes the basis for determining if the accommodation is reasonable under federal law. The purpose of this article is to present a step‐by‐step model to be used as a decision‐making process when considering the accommodation of extended test time for postsecondary students with LD. The model is designed to assist disability service providers in the analysis and synthesis of information collected from (1) the student's diagnostic evaluation, (2) the course or classroom test to be accommodated, and (3) student interviews. A list of diagnostic tests from the four most frequently administered test batteries used with adults is provided, along with a concise explanation of how characteristics of LD impact reading, writing, and math, and relate to the need for extended time. This information can be used to determine if extended test time is a reasonable accommodation and to estimate how much additional time to provide.  相似文献   

Race and Manners for Southern Girls and Boys: “The Miss Minerva” Books and Race Relations in a Southern Children's Series     

John Scott Wilson 《Journal of American culture (Malden, Mass. : 2003)》1994,17(3):69-74

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All I really needed to know I learned during gastrulation          下载免费PDF全文

Gilbert SF 《CBE life sciences education》2008,7(1):12-13

Inept and satisfied, redux.     

T Scott Plutchak 《Journal of the Medical Library Association》2005,93(1):1-3

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Consolidation of Black-dyed Māori Textile Artefacts: Evaluating the Efficacy of Sodium Alginate     

Catherine A. Smith  Rachel A. Paterson  Bronwyn J. Lowe  Rangi Te Kanawa 《文物保护研究》2018,63(3):139-154

Black-dyed artefacts are found in museums worldwide, many produced using an iron-tannate compound. Deterioration of iron-tannate dyed artefacts is an international preservation issue: in New Zealand the deterioration of paru (iron-tannate) dyed Māori textiles is widespread. This article reports experimental work testing the efficacy of sodium alginate, a consolidant developed for deteriorated paru-dyed muka (fibre from harakeke; Phormium tenax). The colour stability, strength retention, and acidity of paru-dyed muka consolidated with sodium alginate (0.25, 0.5, and 1% w/v in water) was tested pre- and post-artificial light ageing. This study found that sodium alginate had no negative effect on paru-dyed muka and in some cases provided benefit. Interestingly, the colour of paru-dyed muka is substantially more stable in UV-filtered light than previously recognised. Also microfading results were in agreement with visual assessments of colour change at 1 Mlux hour exposure, providing confidence in this relatively new technique to assess colour change.  相似文献   

Supportive communication from bystanders of cyberbullying: indirect effects and interactions between source and message characteristics     

Andrew C. High  Rachel Young 《Journal of Applied Communication Research》2018,46(1):28-51

Cyberbullying is an increasingly common experience that produces psychosocial consequences for targets. Interventions encouraging bystanders to support targets of cyberbullying are limited by a lack of focus on what to communicate. This study considers supportive messages that emphasize emotional comfort, attributions of responsibility, and beliefs that people can change as relevant to this context, and it examines how perceptions of messages differ based on whether support providers have or lack experience with cyberbullying. We extend research on the indirect effects model of supportive communication by randomly assigning participants (N?=?304), who self-identify as targets of cyberbullying, to message and source conditions and assessing their perceptions of messages, providers, and outcomes. Impressions of messages mediate their influence on outcomes, and the experiential similarity of support providers moderates these effects. Certain messages, notably those contending that bullies can change, are less effective when delivered by sources who lack experience with bullying.  相似文献   

How we done it good: Research through design as a legitimate methodology for librarianship     

Rachel Ivy Clarke 《Library & information science research》2018,40(3-4):255-261

“How we done it good” publications—a genre concerning project-based approaches that describe how (and sometimes why) something was done—are often rebuked in the library research community for lacking traditional scientific validity, reliability, and generalizability. While scientific methodologies may be a common approach to research and inquiry, they are not the only methodological paradigms. This research posits that the how we done it good paradigm in librarianship reflects a valid and legitimate approach to research. By drawing on the concept of research through design, this study shows how these how we done it good projects reflect design methodologies which draw rigor from process, invention, relevance, and extensibility rather than replicability, generalizability, and predictability. Although these projects implicitly reflect research through design, the methodology is not yet explicitly harnessed in librarianship. More support for these types of projects can be achieved by making the legitimate design framework more explicit and increasing support from publication venues.  相似文献   

Investigating married adults’ communal coping with genetic health risk and perceived discrimination     

Rachel A. Smith  Alan Sillars  Ryan P. Chesnut  Xun Zhu 《Communication monographs》2018,85(2):181-202

Increased genetic testing in personalized medicine presents unique challenges for couples, including managing disease risk and potential discrimination as a couple. This study investigated couples’ conflicts and support gaps as they coped with perceived genetic discrimination. We also explored the degree to which communal coping was beneficial in reducing support gaps and ultimately stress. Dyadic analysis of married adults (N?=?266, 133 couples), in which one person had the genetic risk for serious illness, showed that perceived discrimination predicted more frequent conflicts about alpha-1 antitrypsin deficiency-related treatment, privacy boundaries, and finances, which, in turn, predicted wider gaps in emotion and esteem support, and greater stress for both spouses. Communal coping predicted lower support gaps for both partners and marginally lower stress.  相似文献