How does visual manipulation affect obstacle avoidance strategies used by athletes?     

M. P. Bijman  J. J. Fisher 《Journal of sports sciences》2016,34(10):915-922

Research examining our ability to avoid obstacles in our path has stressed the importance of visual input. The aim of this study was to determine if athletes playing varsity-level field sports, who rely on visual input to guide motor behaviour, are more able to guide their foot over obstacles compared to recreational individuals. While wearing kinematic markers, eight varsity athletes and eight age-matched controls (aged 18–25) walked along a walkway and stepped over stationary obstacles (180° motion arc). Visual input was manipulated using PLATO visual goggles three or two steps pre-obstacle crossing and compared to trials where vision was given throughout. A main effect between groups for peak trail toe elevation was shown with greater values generated by the controls for all crossing conditions during full vision trials only. This may be interpreted as athletes not perceiving this obstacle as an increased threat to their postural stability. Collectively, findings suggest the athletic group is able to transfer their abilities to non-specific conditions during full vision trials; however, varsity-level athletes were equally reliant on visual cues for these visually guided stepping tasks as their performance was similar to the controls when vision is removed.  相似文献   

The effect of 14 weeks of vitamin D3 supplementation on antimicrobial peptides and proteins in athletes     

Cheng-Shiun He  William D. Fraser  Jonathan Tang  Kirsty Brown  Stephen Renwick  Jay Rudland-Thomas 《Journal of sports sciences》2016,34(1):67-74

Heavy training is associated with increased respiratory infection risk and antimicrobial proteins are important in defence against oral and respiratory tract infections. We examined the effect of 14 weeks of vitamin D₃ supplementation (5000 IU/day) on the resting plasma cathelicidin concentration and the salivary secretion rates of secretory immunoglobulin A (SIgA), cathelicidin, lactoferrin and lysozyme in athletes during a winter training period. Blood and saliva were obtained at the start of the study from 39 healthy men who were randomly allocated to vitamin D₃ supplement or placebo. Blood samples were also collected at the end of the study; saliva samples were collected after 7 and 14 weeks. Plasma total 25(OH)D concentration increased by 130% in the vitamin D₃ group and decreased by 43% in the placebo group (both P = 0.001). The percentage change of plasma cathelicidin concentration in the vitamin D₃ group was higher than in the placebo group (P = 0.025). Only in the vitamin D₃ group, the saliva SIgA and cathelicidin secretion rates increased over time (both P = 0.03). A daily 5000 IU vitamin D₃ supplement has a beneficial effect in up-regulating the expression of SIgA and cathelicidin in athletes during a winter training period, which could improve resistance to respiratory infections.  相似文献   

Elite wheelchair rugby: a quantitative analysis of chair configuration in Australia     

David S. Haydon  Ross A. Pinder  Paul N. Grimshaw  William S. P. Robertson 《Sports Engineering》2016,19(3):177-184

Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost.  相似文献   

When Politicians Dodge Questions: An Analysis of Presidential Press Conferences and Debates     

David Clementson  William P. Eveland 《Mass Communication and Society》2016,19(4):411-429

  相似文献   

Curricular Differences and Unidimensionality of Achievement Test Data: An Exploratory Analysis     

S. E. Phillips  William A. Mehrens 《Journal of Educational Measurement》1987,24(1):1-16

The purpose of this study was to investigate whether a linear factor analytic method commonly used to investigate violation of the item response theory (IRT) unidimensionality assumption is sensitive to measurable curricular differences within a school district and to examine the possibility of differential item performance for groups of students receiving different instruction. For grades 3 and 6 in reading and mathematics, personnel from two midwestern school systems that regularly administer standardized achievement tests identified the formal textbook series used and provided ratings of test-instructional match for each school building (classroom). For both districts, the factor analysis results suggested no differences in percentages of variance for large first factors and relatively small second factors across ratings or series groups. The IRT analyses indicated little, if any, differential item performance for curricular subgroups. Thus, the impact of factors that might be related to curricular differences was judged to be minor.  相似文献   

International Review     

Olugbemiro J. Jegede  Barry Fraser  Darrell Fisher Curtin 《Educational technology research and development : ETR & D》1995,43(1):89-90

  相似文献   

Special education and general education preservice teachers’ co-teaching experiences: a comparative synthesis of qualitative research     

Mikyung Shin  Hyunjoo Lee  John William McKenna 《International Journal of Inclusive Education》2016,20(1):91-107

Co-teaching is commonly used to support students with disabilities in inclusive educational settings. However, there is often a gap between the potential effectiveness of co-teaching and actual classroom practice. This study examined preservice teachers’ co-teaching experiences to better understand this gap to identify potential practices for improving teacher training and service delivery. A review of 11 studies revealed that both special education and general education preservice teachers believed that co-teaching practices provided them opportunities to communicate and work collaboratively. Both groups agreed on the significant impact of personality in co-teaching as well as challenges in implementing co-teaching. Furthermore, special education preservice teachers noted that they lacked content knowledge, whereas general education preservice teachers thought they needed more training in the provision of accommodations and modifications. Study limitations, areas for future research, and implications for preservice teacher preparation are discussed.  相似文献   

How can only 18 black teachers working in Liverpool represent a diverse teaching workforce? A critical narrative     

William Boyle  Marie Charles 《International Journal of Inclusive Education》2016,20(8):871-888

This paper follows on from the authors’ previous research into minimal Black teacher representation in Liverpool schools [Boyle, B., and M. Charles. 2010. “Tightening the Shackles: The Continued Invisibility of Liverpool's British African Caribbean Teachers.” Journal of Black Studies 42 (3): 427–435]. It is based on a re-examination of their findings of Liverpool's Black teachers’ historic institutionalised invisibility [Swann Report. 1985. Education for All. Report of the Committee of the Enquiry into the Education of Children from Ethnic Minority Groups. London: Her Majesty's Stationery Office.] and an interrogation of the situation as revealed by the 2015 data. The article uses as its evidence base, questionnaire responses and data from a sample of interviews with the current 18 Black teachers. Despite the voices of Black teachers being marginalised and even less likely to be heard, it is vital that the pedagogies of Black teachers contribute to a ‘dismantling of binaries and hierarchies that privilege Eurocentric paradigms of teaching’ [Escayg, K. 2010. “Diverse Classrooms, Diverse Teachers: Representing Cultural Diversity in the Teaching Profession and Implications for Pre-Service Admissions.” Canadian Journal for new Scholars in Education 3 (2): 1–8, 4].  相似文献   

The Inclusion of Informal Environments in Science Teacher Preparation     

Olson  Joanne K.  Cox-Petersen  Anne M.  McComas  William F. 《Journal of Science Teacher Education》2001,12(3):155-173

Journal of Science Teacher Education -  相似文献   

Critiquing Theory of Planned Behaviour as a method to assess teachers' technology integration attitudes     

William Sugar  Frank Crawley  Bethann Fine 《British journal of educational technology : journal of the Council for Educational Technology》2005,36(2):331-334

  相似文献