Differences in trunk and upper extremity kinematics and segmental velocities during the offside forehand polo swing between male and female athletes     

Gretchen D. Oliver  Gabrielle G. Gilmer  Jeff W. Barfield  Abigail R. Brittain 《Journal of sports sciences》2013,31(17):2007-2013

ABSTRACT

Although polo is a well-known equestrian sport, it is fundamentally misunderstood. The purpose of this study was to examine trunk and upper extremity kinematics and segmental velocities during the offside forehand polo swing between male and female athletes. Ten female and 17 male professional polo athletes volunteered. An electromagnetic tracking system collected kinematic data at 100 Hz while participants performed three offside forehand polo swings from a stationary wooden horse. One-way ANOVAs revealed statistically significant differences (p<0.05) in all kinematic variables and segmental velocities. Specifically, males exhibited a greater mean difference (MD=23°) of trunk flexion at take away (TA) and top of backswing (TOB)(MD=29°) trunk lateral flexion at ball contact (BC)(MD=23°), trunk rotation at TA(MD=97°) and TOB(MD=118°), shoulder abduction at TOB(MD=64°), and shoulder elevation at TOB(MD=13°) and BC(MD=40°). Females displayed greater trunk rotation at BC(MD=91°), shoulder elevation at TA(MD=19°), and elbow flexion at TA(MD=90°). Additionally, females generated greater segmental velocities early in the swing, while the males generated velocity later. The movement patterns observed amongst the males suggest energy is being transferred more efficiently along the kinetic chain, thus more efficient swing mechanics, but further investigation into the role of the trunk and lumbopelvic-hip complex in reference to the polo swing is warranted.  相似文献   

Assessing attitude towards religion: the Astley–Francis Scale of Attitude towards Theistic Faith     

Jeff Astley  Mandy Robbins 《British Journal of Religious Education》2012,34(2):183-193

This study builds on the research tradition modelled by the Francis Scale of Attitude towards Christianity, the Katz–Francis Scale of Attitude towards Judaism, the Sahin–Francis Scale of Attitude towards Islam and the Santosh–Francis Scale of Attitude towards Hinduism to propose a generic instrument concerned with attitudes towards theistic faith. The scale properties of this new instrument, established among a sample of 284 (200 female and 84 male) 16–18-year-old students, commend it for use in future research.  相似文献   

A Placement Test for Computer Science: Design,Implementation, and Analysis     

Gwen Nugent  Leen-Kiat Soh  Ashok Samal  Jeff Lang 《Computer Science Education》2013,23(1):19-36

An introductory CS1 course presents problems for educators and students due to students' diverse background in programming knowledge and exposure. Students who enroll in CS1 also have different expectations and motivations. Prompted by the curricular guidelines for undergraduate programmes in computer science released in 2001 by the ACM/IEEE, and driven by a departmental project to reinvent the undergraduate computer science and computer engineering curricula at the University of Nebraska-Lincoln, we are currently implementing a series of changes which will improve our introductory courses. One key component of our project is an online placement examination tied to the cognitive domain that assesses student knowledge and intellectual skills. Our placement test is also integrated into a comprehensive educational research design containing a pre- and posttest framework for assessing student learning and providing valuable feedback for needed instructional revisions. In this paper, we focus on the design and implementation of our placement exam and present an analysis of the data collected to date.  相似文献   

CHRISTIAN EDUCATION AND OPENNESS: AN EMPIRICAL INVESTIGATION AMONG UNDERGRADUATES     

Jeff Astley  Leslie J. Francis 《Religious education (Chicago, Ill.)》2013,108(1):4-22

A sample of 334 undergraduates completed the Francis Scale of Attitude Toward Christianity and the Astley-Francis Open Worldview Scale, together with the short form Revised Eysenck Personality Questionnaire. The data provide no support for the view that a positive attitude toward Christianity inhibits openness to other worldviews, although both attitude toward Christianity and the adoption of an open worldview are significantly related to individual differences in personality.  相似文献   

春天的承诺     

Jeff Rennicke 《中文自修》2009,(5)

冬天过去了,但我们还清楚地记得,当刺骨的寒风吹来,我们不由地缩起脖子,裹紧大衣。冬,似乎是寒意,是肃杀,是销声匿迹……然而,即使在最寒冷的日子里,也别忘了倾听生命的迹象,它来自自然,来自生活,来自内心希望的涌动。下面我们就一起来欣赏一篇在冬日里写下的《春天的承诺》。  相似文献   

Assessment of model-based image-matching for future reconstruction of unhelmeted sport head impact kinematics     

Gregory J. Tierney  Hamed Joodaki  Tron Krosshaug  Jason L. Forman  Jeff R. Crandall  Ciaran K. Simms 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(1):33-47

Player-to-player contact inherent in many unhelmeted sports means that head impacts are a frequent occurrence. Model-Based Image-Matching (MBIM) provides a technique for the assessment of three-dimensional linear and rotational motion patterns from multiple camera views of a head impact event, but the accuracy is unknown for this application. The goal of this study is to assess the accuracy of the MBIM method relative to reflective marker-based motion analysis data for estimating six degree of freedom head displacements and velocities in a staged pedestrian impact scenario at 40 km/h. Results showed RMS error was under 20 mm for all linear head displacements and 0.01–0.04 rad for head rotations. For velocities, the MBIM method yielded RMS errors between 0.42 and 1.29 m/s for head linear velocities and 3.53–5.38 rad/s for angular velocities. This method is thus beneficial as a tool to directly measure six degree of freedom head positional data from video of sporting head impacts, but velocity data is less reliable. MBIM data, combined in future with velocity/acceleration data from wearable sensors could be used to provide input conditions and evaluate the outputs of multibody and finite element head models for brain injury assessment of sporting head impacts.  相似文献   

Fostering the academic success of their children: Voices of Mexican immigrant parents     

Jill S. Goldsmith  Sharon E. Robinson Kurpius 《The Journal of educational research》2018,111(5):564-573

Latinos, particularly Mexican immigrants, are the fastest-growing population in the United States but lag behind others in educational attainment. Parent involvement in their child's education has been linked to positive student academic outcomes, but few studies have focused specifically on Latino/a parents. To identify and promote culturally salient parent involvement approaches for Mexican immigrant parents, this qualitative strength-based study investigated motivations, actions, and culture of 11 Mexican immigrant parents of students who attended a selective college preparatory high school. The study found that a parent's effort to help their children succeed is not dependent on high levels of parent education or income. Rather, the home-based strategies, many of which are rooted in the Latino culture, and specific outreach by educators influenced parent involvement.  相似文献   

Teachers' perceptions of students' excuses for academic difficulties     

Nona Tollefson  Susan Hsia  Jeff Townsend 《Psychology in the schools》1991,28(2):146-155

Ninety-seven teachers described situations in which their students experienced academic difficulties and gave reasons (excuses) to explain their difficulties. Teachers indicated whether or not they believed the reasons students gave, what they thought the “real” reasons for the students' difficulties were, and how they reacted and behaved toward the students. Analysis of teachers' reports indicated that students were most likely to attribute their academic difficulties to external, uncontrollable factors, whereas teachers tended to believe that the “real” reasons for students' difficulties were internal and controllable. Teachers reported that they would react in a positive manner toward the students whether or not they believed the reasons the students gave to explain their difficulties. Implications of these findings for student motivation are discussed.  相似文献   

Of Mice and Manga: Comics and Graphic Novels in Art Education     

Jeff Adams 《The International Journal of Art & Design Education》1999,18(1):69-75

A justification for the inclusion of graphic comic art in post-14 art education following the development of graphic novels in Europe, Japan and the USA. in recent years. The case is based on the visual dynamics of the medium and the potential for a critical realism which can be exploited in students’ studio practice and research. Particular attention is given to the Holocaust novel Maus and selected Japanese ‘Manga’ comics which have made an impact in the west, such as Barefoot Gen and Adolf. The article analyses the various innovative visual forms that these graphic novels utilise and considers their effectiveness as a vehicle for practice and research in the institutional art curriculum.  相似文献   

Building Bridges: Reflections on the problem of transfer of learning in mathematics     

Jeff Evans 《Educational Studies in Mathematics》1999,39(1-3):23-44

The takeup of opportunities for applying formal learning outside the school is often disappointing – to teachers, parents, employers, and many pupils. Not surprisingly, there is much controversy among researchers in mathematics education and related fields, as to the reasons. Here I argue that neither traditional nor constructivist views, with their simplistic faith in the basic continuity of knowledge across contexts, nor currently popular ‘insulationist’ views such as the strong form of situated cognition, which claims that transfer is basically not possible, are adequate. Instead, I analyse why transfer is problematical in principle, and undependable in practice. I recommend an alternative approach for building bridges between practices, based on analysing the discourses involved as systems of signs, and looking for appropriate points of inter-relation between them. In this reconceptualisation of the ‘problem’ of transfer, the role of affective factors, previously under-examined in the literature, is highlighted. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献