Effects of changing speed on knee and ankle joint load during walking and running

Joint moments can be used as an indicator of joint loading and have potential application for sports performance and injury prevention. The effects of changing walking and running speeds on joint moments for the different planes of motion still are debatable. Here, we compared knee and ankle moments during walking and running at different speeds. Data were collected from 11 recreational male runners to determine knee and ankle joint moments during different conditions. Conditions include walking at a comfortable speed (self-selected pacing), fast walking (fastest speed possible), slow running (speed corresponding to 30% slower than running) and running (at 4 m · s^?1 ± 10%). A different joint moment pattern was observed between walking and running. We observed a general increase in joint load for sagittal and frontal planes as speed increased, while the effects of speed were not clear in the transverse plane moments. Although differences tend to be more pronounced when gait changed from walking to running, the peak moments, in general, increased when speed increased from comfortable walking to fast walking and from slow running to running mainly in the sagittal and frontal planes. Knee flexion moment was higher in walking than in running due to larger knee extension. Results suggest caution when recommending walking over running in an attempt to reduce knee joint loading. The different effects of speed increments during walking and running should be considered with regard to the prevention of injuries and for rehabilitation purposes.     

The impact of data reduction on the intra-trial reliability of a typical measure of lower limb musculoskeletal stiffness

Double-leg repeated jumping tasks are commonly used as measures of lower limb stiffness in exercise science research. Within similar stiffness calculations, variation in data-reduction criteria exists. The impact of these varied data-reduction methods on stiffness measures is unknown. Sixteen adolescent female participants from varied physical activity backgrounds performed 15 self-paced, bent-knee continuous jumps (CJb) on two force plates. Leg stiffness was calculated as the ratio of the peak force and the centre of mass displacement for each contact. Using combinations of criteria based on previous literature, 83 data-reduction methods were applied to the raw data. Data reduction suitability was assessed based on intra-trial reliability, the number of participants excluded and the average contacts excluded. Four data-reduction methods were deemed suitable for use with adolescent female populations, with three consecutive contacts within 1 SD of the average jump frequency considered optimal. The average individual stiffness values were not greatly influenced by the data-reduction method; however, for a single participant, a stiffness change of up to 6 kN · m^?1 (30%) was observed. The role and potential impact of data-reduction methods used to evaluate measures of lower limb stiffness during repeated jumping tasks warrants consideration.     

Making News Today: a tool for adoption of ethics principles using technology‐supported television journalism

There are movements internationally towards curricula that incorporate values and citizenship education. In Australia, this movement has been illustrated with the adoption of a national curriculum in values education. This has arisen from the perceived need for citizens to hold values around the rights and responsibilities of functioning within a democracy. The Making News Today programme has been designed to develop a range of literacies enabling learners, for example, to read the media beyond the interests of the elite. The programme incorporates a journalistic process for television news production for middle school students using laptop and handheld video technologies, with embedded ethics and values education. The article reports on an analysis of the implementation of this programme with middle school students in Australia with reference to student adoption of ethical stances in the journalistic process and the implications for the use of this project in developing ethics, values and citizenship as part of the curriculum process.     

A Comprehensive Analysis of High School Genetics Standards: Are States Keeping Pace with Modern Genetics?

Science education in the United States will increasingly be driven by testing and accountability requirements, such as those mandated by the No Child Left Behind Act, which rely heavily on learning outcomes, or "standards," that are currently developed on a state-by-state basis. Those standards, in turn, drive curriculum and instruction. Given the importance of standards to teaching and learning, we investigated the quality of life sciences/biology standards with respect to genetics for all 50 states and the District of Columbia, using core concepts developed by the American Society of Human Genetics as normative benchmarks. Our results indicate that the states' genetics standards, in general, are poor, with more than 85% of the states receiving overall scores of Inadequate. In particular, the standards in virtually every state have failed to keep pace with changes in the discipline as it has become genomic in scope, omitting concepts related to genetic complexity, the importance of environment to phenotypic variation, differential gene expression, and the differences between inherited and somatic genetic disease. Clearer, more comprehensive genetics standards are likely to benefit genetics instruction and learning, help prepare future genetics researchers, and contribute to the genetic literacy of the U.S. citizenry.     

Modifications of Recognition Memory Processes in Preterm Children: An Event‐Related Potential Study

Prematurity may cause hippocampal compromise. Therefore, hippocampus‐dependent memory processes (recollection‐based retrieval) may be more impaired than hippocampus‐independent processes (familiarity‐based retrieval). The memory of 18 children born preterm with reduced hippocampal volumes, without neonatal complications (weeks of gestation < 34, weight < 1,600 g), and 15 controls (8–10 years) was tested using an item recognition task. While groups were equal in memory performance, dissociation was found: The event‐related potential (ERP) correlate of familiarity was intact in the preterm group, whereas the correlate of recollection was attenuated. A follow‐up experiment ruled out that this was due to general cognitive deficits. Furthermore, gestational age correlated with the ERP index of recollection. Thus, recognition memory in preterm children may be characterized by a compensation of attenuated recollection by familiarity.     

Finding knowledge on the Internet: implications for the knowledge-driven curriculum

This article offers a critique of Michael Young’s perspective on the Internet as it relates to the knowledge-driven curriculum he supports. I argue that the Internet is a site of both theoretical knowledge and everyday concepts which challenges the differentiation of knowledge that premises much of Young’s writing. Google searches from the perspective of a student and teacher show that theoretical knowledge with vertical links to subject and disciplinary communities as well as coherence built through links between concepts is fairly readily accessed on the Internet. The importance of information literacy for students, the critical need to curate content on the web, as well as the implications for the curriculum of framing ‘knowing’ as encompassing ‘being familiar’ and comprehending’ are highlighted.