Shoe collar height and heel counter-stiffness for shoe cushioning and joint stability in landing

ABSTRACT

This study examined the effects of shoe collar-height and counter-stiffness on ground reaction force (GRF), ankle and knee mechanics in landing. Eighteen university basketball players performed drop landing when wearing shoes in different collar height (high vs. low) and counter-stiffness (stiffer vs. less stiff). Biomechanical variables were measured with force platform and motion capturing systems. Two-way repeated measures ANOVA was performed with α = 0.05. Wearing high collar shoes exhibited smaller peak ankle dorsiflexion and total sagittal RoM, peak knee extension moment, but larger peak knee varus moment than the low collar shoes. Stiffer counter-stiffness shoes related to smaller ankle inversion at touchdown and total coronal RoM, but larger peak knee flexion and increased total ankle and knee sagittal RoM than the less stiff counter-stiffness. Furthermore, wearing stiffer counter-stiffness shoes increased forefoot GRF peak at high collar condition, while no significant differences between counter-stiffness at low collar condition. These results suggest that although higher collar height and/or stiffness heel counter used can reduce ankle motion in coronal plane, it would increase the motion and loading at knee joint, which is susceptible to knee injuries. These findings could be insightful for training and footwear development in basketball.     

冬奥会五大难忘时刻

悲剧赛道 这一悲伤时刻将永远笼罩着温哥华冬奥会.2月12日,就在开幕式开始前的几个小时,诺达尔·库玛丽塔什维利,一位来自格鲁吉亚的单人雪橇运动员,在训练中通过惠斯勒赛道的最后一个弯道时,撞上赛道内墙,突然弹出,撞上了赛迫外的钢柱,后不治身亡,年仅21岁.     

Numerical study of dc-biased ac-electrokinetic flow over symmetrical electrodes

This paper presents a numerical study of DC-biased AC-electrokinetic (DC-biased ACEK) flow over a pair of symmetrical electrodes. The flow mechanism is based on a transverse conductivity gradient created through incipient Faradaic reactions occurring at the electrodes when a DC-bias is applied. The DC biased AC electric field acting on this gradient generates a fluid flow in the form of vortexes. To understand more in depth the DC-biased ACEK flow mechanism, a phenomenological model is developed to study the effects of voltage, conductivity ratio, channel width, depth, and aspect ratio on the induced flow characteristics. It was found that flow velocity on the order of mm/s can be produced at higher voltage and conductivity ratio. Such rapid flow velocity is one of the highest reported in microsystems technology using electrokinetics.     

Academic self‐concept,gender and single‐sex schooling

This article assesses gender differences in academic self‐concept for a cohort of children born in 1958 (the National Child Development Study). It addresses the question of whether attending single‐sex or co‐educational schools affected students' perceptions of their own academic abilities (academic self‐concept). Academic self‐concept was found to be highly gendered, even controlling for prior test scores. Boys had higher self‐concepts in mathematics and science, and girls in English. Single‐sex schooling reduced the gender gap in self‐concept, while selective schooling was linked to lower academic self‐concept overall.     

What are the affective and social outcomes for low-achieving students within an inclusive school in Hong Kong?

In response to several major curriculum reforms in Hong Kong since 2000, schools were required to initiate policies that catered for learner diversity. As well academic achievement, the reforms also emphasized the affective and social outcomes of the learning experience. A whole-school approach to learner diversity includes students with low academic achievement and mild disabilities, with schools being free to develop policies and practices inline with the needs of the students, teachers, and parents. Against the Chinese cultural context, where high academic achievement is highly valued, this study describes the affective and social outcomes of students in one Hong Kong primary school that streamed students according to achievement level. Four hundred and ten students across Primary 3–5 responded to four instruments measuring academic self-concept, alienation from school, teacher–students relationship, and social integration. The responses showed that, when studying the regular curriculum, students in the low-achievement group reported greater levels of alienation and lowest levels of social integration compared with students with the highest levels of achievement. On the other hand, low-achieving students who studied a differentiated curriculum reported affective and social outcomes more consistent with the responses from the high-achieving students. The results suggest that there is a mismatch between the aims and practice of the educational policy reflecting learner diversity and the cultural expectations of both parents and students.     

Awareness within local authorities in England of autism spectrum diagnoses of looked-after children

Educational outcomes for looked-after children on the autism spectrum are significantly poorer than for autistic children not being looked-after by their local authority (those ‘in care’), and poorer than for most other groups of children with special educational needs who are looked-after in England. Such poor outcomes have led to calls for specific attention to be paid to the needs of autistic looked-after children within the care of local authorities. There is also evidence that the numbers of autistic children being looked-after by local authorities could be under-represented in official figures. This study sought to find the current numbers of autistic looked-after children formally recorded across local authorities in England, and whether their needs are given special attention via strategic planning and oversight, using freedom of information (FoI) requests sent to all local authorities in England. From the 147 (97%) local authorities who responded, approximately 3% of looked-after children in England are recorded as having an autism spectrum diagnosis, although this is still very likely to be an underestimation. The majority of local authorities do not routinely monitor or report on the diagnostic status of autistic looked-after children at a strategic level. Implications for research and practice are discussed.