Kinematic analysis of hip and knee rotation and other contributors to ballet turnout

Turnout, or external rotation (ER) of the lower extremities, is essential in ballet. The purpose of this study was to utilise physical examination and a biomechanical method for obtaining functional kinematic data using hip and knee joint centres to identify the relative turnout contributions from hip rotation, femoral anteversion, knee rotation, tibial torsion, and other sources. Ten female dancers received a lower extremity alignment assessment, including passive hip rotation, femoral anteversion, tibial torsion, weightbearing foot alignment, and Beighton hypermobility score. Next, turnout was assessed using plantar pressure plots and three-dimensional motion analysis; participants performed turnout to ballet first position on both a plantar pressure mat and friction-reducing discs. A retro-reflective functional marker motion capture system mapped the lower extremities and hip and knee joint centres. Mean total turnout was 129±15.7° via plantar pressure plots and 135±17.8° via kinematics. Bilateral hip ER during turnout was 49±10.2° (36% of total turnout). Bilateral knee ER during turnout was 41±5.9° (32% of total turnout). Hip ER contribution to total turnout measured kinematically was less than expected compared to other studies, where hip ER was determined without functional kinematic data. Knee ER contributed substantially more turnout than expected or previously reported. This analysis method allows precise assessment of turnout contributors.     

Changes in kinematics and arm–leg coordination during a 100-m breaststroke swim

The purpose of this study was to compare arm–leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm–leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P < 0.05) were found between laps. Both sexes showed significant increase (P < 0.05) in heart rate and blood lactate pre- to post-swim. Males had significantly (P < 0.01) faster swim velocities resulting from longer SLs (P = 0.016) with no difference in SR (P = 0.064). Sex differences in kinematic parameters can be explained by anthropometric differences providing males with increased propelling efficiency.     

A knock to the system: A new sociotechnical systems approach to sport-related concussion

Broader contextual factors that influence concussion management have tended to be overlooked. To address this, the present study used a sociotechnical systems approach to identify perceived responsibilities and applied strategies for three domains of concussion management (i.e., prevention, identification and treatment). Participants were 118 members of the community rugby union system in Australia (69.2% male). Participants from throughout the rugby system (e.g., players, parents, coaches, club management) were asked open-ended questions about their perceived responsibilities and the strategies they use for concussion management. It was found that (a) proper training, technique correction and education were recurrent prevention themes; (b) the majority of key stakeholders felt that they could consistently identify concussion; however, medical aids (medics) were the only system actors who stated a responsibility to use standardised concussion assessment measures and (c) less than one third of the respondents indicated their involvement in treating concussion. This study identifies specific junctures in the system that prevents effective concussion management strategies. A sociotechnical systems approach improves the understanding of concussion prevention, and management beliefs and behaviours.     

A genealogical analysis of Peter Arnold's conceptual account of meaning in movement,sport and physical education

We write as critical theorists who share an interest in how conceptions of physical education are taken forward in policy and practice. In this respect, we are particularly intrigued by Peter Arnold's conceptual account of meaning in movement, sport and physical education, and the subsequent ways in which his ideas have informed national curriculum ambitions. Despite the prominence of Arnold's influence, we are concerned that there has been an insufficiently rigorous and robust review of his theorising to date, particularly in relation to where his ideas originated from. Accordingly, we critically discuss the merits of adopting a genealogical approach in order to support a detailed analysis of Arnold's conceptual account of meaning in movement, sport and physical education; one which especially focuses on learning ‘about’, ‘through’ and ‘in’ movement. We conclude by questioning a number of the complex strands of Arnold's work in the expectation that greater lucidity and purpose can emerge. This it is argued will be beneficial in terms of providing clarity on aim or aims statements in physical education, which in turn can secure greater policy coherence and practice gains.     

关于数学分析课程中思想方法的教学

通过教学案例说明怎样进行思想方法教学,以促进本科数学专业数学分析的教学与研究.     

生态化治理模式在规模化畜禽养殖业的应用及成效

对生态化治理模式在规模化畜禽养殖业的应用及成效进行了分析、研究。结果表明,生态化治理模式对规模化畜禽养殖场污水治理效果显著,值得在中小型规模化畜禽养殖企业中推广应用。     

英汉使役结构的距离象似性对比分析

距离象似性是语言成分间首要的象似原则。本文对比分析了英汉使役结构的距离象似性特点,发现：英语用综合式表达直接使役,用分析式表达间接使役,形式上的距离对应于概念上的距离,体现了距离象似性;而汉语的＂把＂字句和复合动词组成的句子表达的是直接役使,＂使＂字句表达的是间接使役,也充分符合距离象似原则。     

音乐剧的古典风格及演唱分析

音乐剧的音乐形式是歌剧化的,它是古典歌剧艺术的现代传承,是现代音乐戏剧的主流。古典风格音乐剧的演唱中具有独特个性,文章从古典风格音乐剧及其流行演唱风格、剧目、歌曲等方面对音乐剧具体的演唱环节进行了分析。     

农民组织与基层政权的互动及其后果

日益兴起的农民组织是农民之福还是国家之祸？国家与社会在基层政治场域集中体现为农民组织与基层政权,本文借助于类型学的研究方法,对农民组织与基层政权的关系进行分类研究,促成认识的清晰化,分析关系成因,预测其政治后果,在理论上探寻农民组织与基层政权关系的理想模式,提出对农民组织的分类管理策略。     

数组函数在状态数据采集平台数据分析中的应用

介绍了在人才培养工作状态数据采集平台中使用数组函数,对专任教师队伍的结构、专任教师的教学工作量、专业课程开设情况等几个数据表进行数据统计分析的方法.