The effects of mid-flight whole-body and trunk rotation on landing mechanics: implications for anterior cruciate ligament injuries

ABSTRACT

The purpose was to quantify the effects of mid-flight whole-body and trunk rotation on knee mechanics in a double-leg landing. Eighteen male and 20 female participants completed a jump-landing-jump task in five conditions: no rotation, testing leg ipsilateral or contralateral (WBRC) to the whole-body rotation direction, and testing leg ipsilateral (TRI) or contralateral to the trunk rotation direction. The WBRC and TRI conditions demonstrated decreased knee flexion and increased knee abduction angles at initial contact (2.6 > Cohen’s dz > 0.3) and increased peak vertical ground reaction forces and knee adduction moments during the 100 ms after landing (1.7 > Cohen’s dz > 0.3). The TRI condition also showed the greatest knee internal rotation angles at initial contact and peak knee abduction and internal rotation angles and peak knee extension moments during the 100 ms after landing (2.0 > Cohen’s dz > 0.5). Whole-body rotation increased contralateral knee loading because of its primary role in decelerating medial-lateral velocities. Trunk rotation resulted in the greatest knee loading for the ipsilateral knee due to weight shifting and mechanical coupling between the trunk and lower extremities. These findings may help understand altered trunk motion in anterior cruciate ligament injuries.     

Minds Under Siege: Cognitive Signatures of Poverty and Trauma in Refugee and Non-Refugee Adolescents

The impacts of war and displacement on executive function (EF)—what we might call the cognitive signatures of minds under siege—are little known. We surveyed a gender-balanced sample of 12- to 18-year-old Syrian refugees (n = 240) and Jordanian non-refugees (n = 210) living in Jordan. We examined the relative contributions of poverty, trauma exposure, posttraumatic stress, and insecurity to variance in inhibitory control and working memory. We observed associations between poverty and WM, suggesting that, even in populations exposed to substantial violence and fear, poverty is a specific pathway to WM deficit. We did not, however, find associations between EFs and exposures to trauma. Careful distinction between childhood adversities may illuminate which neurocognitive pathways matter for measures of cognitive function.     

Getting up close with Taoist: Chinese perspectives on physical literacy

PROSPECTS - This article argues that ancient Chinese Tao (“The Way”) philosophy—which can be traced back more than two thousand years—can explain the essence and philosophy...     

Teaching the partial products algorithm with the concrete representational abstract sequence and the strategic instruction model

Elementary standards include multiplication of single-digit numbers and students advance to solve complex problems and demonstrate procedural fluency in algorithms. The ability to illustrate procedural fluency in algorithms is dependent on the development of understanding and reasoning in multiplication. Development of multiplicative reasoning provides the foundation for advanced mathematics and algebraic reasoning. For students who struggle in mathematics, instruction in multiplication algorithms should ensure conceptual understanding so that students have a foundation for success in advanced mathematics. The concrete representational abstract (CRA) sequence addresses conceptual understanding and the strategic instruction model (SIM) supports procedural knowledge. The current pilot study combined these methods to teach elementary students the partial products algorithm. Twelve students in grades four and five participated in the study, receiving instruction from teachers in their school during an intervention period. Within a pre-experimental design, using pre- and postintervention data, students showed a significant change in performance. The article will describe and show how teachers implemented the CRA-SIM interventions and discuss implications for practice.     

Teaching Subtraction and Multiplication with Regrouping Using the Concrete‐Representational‐Abstract Sequence and Strategic Instruction Model

Based on Common Core Standards (2010), mathematics interventions should emphasize conceptual understanding of numbers and operations as well as fluency. For students at risk for failure, the concrete‐representational‐abstract (CRA) sequence and the Strategic Instruction Model (SIM) have been shown effective in teaching computation with an emphasis on conceptual understanding. No studies have investigated the effects of CRA and SIM for teaching multiplication with regrouping. Therefore, the purpose of this study was to replicate and extend the literature, teaching subtraction and multiplication with regrouping using CRA and SIM. Three students receiving tier three mathematics interventions participated. A multiple‐probe across behaviors design was used to show a functional relation. All of the students demonstrated increases in fluency across all regrouping tasks.     

From peripheral to full participation in a blended trade bargaining simulation

This article considers the extent and nature of student participation in a trade bargaining simulation from a community of practice perspective. This third‐year economics module included a blend of online communication (through email, online chats and online discussions) and face‐to‐face meetings, both in smaller bargaining groups and in whole class plenary meetings. Our method of analysis includes the use of Exchange Structure Analysis of text chats and face‐to‐face learning conversations, triangulated by observation, survey and interview data. The focus on community of practice enables us to offer a nuanced interpretation of differences in crude participation data derived from the online chats. Superficially, the data may suggest marginalisation of participants, but Wenger's (1988 ) notion of peripheral participation with a trajectory towards full participation reframes the disparities in terms of an active community of practice. Some members are fully engaged with the practices of trade bargaining from the early stages of the simulation, while others move towards full participation over the duration of the simulation. Our results suggest that the laboratory‐based online text chats did provide opportunities for student participation in the simulation, and that male and female students exhibited different patterns of participation in the chats.     

What's in a game? A study of games as an instructional method in an adult education class

An experiential approach employing game design and play was tried in a graduate adult education class. This article describes a follow-up study which attempted to capture class members' perceptions on value of game design/play; group interactions in game development; effectiveness of game design/play as a learning stimulant; appropriateness of the grading criteria; likelihood to use a similar strategy in their own teaching; and, identification of helpful resources in gaming. Game design/play appears to offer an effective adult teaching strategy which produces a variety of learning outcomes.Jessica Somers earned her BBA and MBA degrees at West Georgia College. She is currently a doctoral student in instructional technology at the University of Georgia and is a self-employed computer contractor.Margaret E. Holt is associate professor of adult education at the University of Georgia and is an associate with the Charles F. Kettering Foundation. Her most recent publication is a book co-edited with Dr. George Lopos for Jossey-Bass Publishers entitled,Perspectives on Educational Certificate Programs (Winter 1991). She is also a former editor ofInnovative Higher Education.     

Assessing the importance of subvocalization during normal silent reading

A concurrent speaking paradigm was used to assess the importance of subvocalization during the reading of lengthy natural prose passages. Experiment 1 showed that having subjects count aloud while reading interfered with their comprehension and recall of the text's details as well as its gist, but did not affect the durability of the memory trace. Experiment 2 replicated these findings and established the validity of using concurrent speaking as a technique to interfere with speech-specific processes during silent reading. By pitting concurrent speaking against a nonverbal concurrent task, Experiment 2 provided evidence that its detrimental effect on comprehension was due to a competition for speech-related resources rather than a general competition for cognitive resources. Interfering with speech recoding during silent reading led to an average decrement of 10–12% in comprehension performance. However, Experiment 2 also showed that there were substantial individual differences in the magnitude of the speech interference effect and that these differences were systematically related to subjective reports about the concurrent speaking manipulation.     

Integrating Writing into the Early Childhood Curriculum: A Frame for Intentional and Meaningful Writing Experiences

Despite the importance of early writing development to children’s school success, research documents that early childhood teachers spend little time actively supporting children’s writing development in preschool classrooms. This article provides a framework for integrating writing experiences across the early childhood curriculum. Practical examples are given regarding how writing opportunities can be incorporated into existing activities and play settings. The metaphor of backgrounding and foregrounding writing experiences is used to illustrate ways that teachers can set writing rich environments and activities in a manner that makes it easier for teachers to bring these experiences into everyday learning opportunities. Attention is given to how teachers can bring writing to the foreground of the curriculum by drawing attention to writing materials, making natural connections with children’s interest and play, and scaffolding children’s early writing attempts and experiences.     

Choosing Strategies of Children and the Impact of Age and Gender on Library Use: Insights for Librarians

Libraries continue to be an important source of books for young people, though relatively little is known about how gender and age influence visitation frequency for this purpose. In addition, while supporting children to choose books is part of the role of both school and public librarians, little is known about the strategies and processes children use to select books, and the beliefs and attitudes that underpin them. Findings from the 2016 Western Australian Study in Children's Book Reading offer insights into these areas that can support librarians to guide book choice, and they encourage targeted intervention to ensure that boys and older children make use of their libraries to support their literacy growth.