Impact of harness attachment point on kinetics and kinematics during sled towing.

Resisted sprint training is performed in a horizontal direction, and involves similar muscles, velocities and ranges of motion (ROM) to those of normal sprinting. Generally, sleds are attached to the athletes via a lead (3m) and harness; the most common attachment points are the shoulder or waist. At present, it is not known how the different harness point's impact on the kinematics and kinetics associated with sled towing (ST). The aim of the current investigation was to examine the kinetics and kinematics of shoulder and waist harness attachment points in relation to the acceleration phase of ST. Fourteen trained males completed normal and ST trials, loaded at 10% reduction of sprint velocity. Sagittal plane kinematics from the trunk, hip, knee and ankle were measured, together with stance phase kinetics (third foot-strike). Kinetic and kinematic parameters were compared between harness attachments using one-way repeated measures analysis of variance. The results indicated that various kinetic differences were present between the normal and ST conditions. Significantly greater net horizontal mean force, net horizontal impulses, propulsive mean force and propulsive impulses were measured (p>0.05). Interestingly, the waist harness also led to greater net horizontal impulse when compared to the shoulder attachment (p = 0.000). In kinematic terms, ST conditions significantly increased peak flexion in hip, knee and ankle joints compared to the normal trials (p<0.05). Results highlighted that the shoulder harness had a greater impact on trunk and knee joint kinematics when compared to the waist harness (p<0.05). In summary, waist harnesses appear to be the most suitable attachment point for the acceleration phase of sprinting. Sled towing with these attachments resulted in fewer kinematic alterations and greater net horizontal impulse when compared to the shoulder harness. Future research is necessary, in order to explore the long-term adaptations of these acute changes

The Rise and Fall, and the Rise (Again) of Feminist Research in Music: 'What Goes Around Comes Around'

This article reports from a two-phase study that involved an analysis of the extant literature followed by a three-part survey answered by seventy-one women composers. Through these theoretical and empirical data, the authors explore the relationship between gender and music’s symbolic and cultural capital. Bourdieu’s theory of the habitus is employed to understand the gendered experiences of the female composers who participated in the survey. The article suggests that these female composers have different investments in gender but that, overall, they reinforce the male habitus given that the female habitus occupies a subordinate position in relation to that of the male. The findings of the study also suggest a connection between contemporary feminism and the attitudes towards gender held by the participants. The article concludes that female composers classify themselves, and others, according to gendered norms and that these perpetuate the social order in music in which the male norm dominates

The western painted turtle genome, a model for the evolution of extreme physiological adaptations in a slowly evolving lineage

BackgroundWe describe the genome of the western painted turtle, Chrysemys picta bellii, one of the most widespread, abundant, and well-studied turtles. We place the genome into a comparative evolutionary context, and focus on genomic features associated with tooth loss, immune function, longevity, sex differentiation and determination, and the species' physiological capacities to withstand extreme anoxia and tissue freezing.ResultsOur phylogenetic analyses confirm that turtles are the sister group to living archosaurs, and demonstrate an extraordinarily slow rate of sequence evolution in the painted turtle. The ability of the painted turtle to withstand complete anoxia and partial freezing appears to be associated with common vertebrate gene networks, and we identify candidate genes for future functional analyses. Tooth loss shares a common pattern of pseudogenization and degradation of tooth-specific genes with birds, although the rate of accumulation of mutations is much slower in the painted turtle. Genes associated with sex differentiation generally reflect phylogeny rather than convergence in sex determination functionality. Among gene families that demonstrate exceptional expansions or show signatures of strong natural selection, immune function and musculoskeletal patterning genes are consistently over-represented.ConclusionsOur comparative genomic analyses indicate that common vertebrate regulatory networks, some of which have analogs in human diseases, are often involved in the western painted turtle's extraordinary physiological capacities. As these regulatory pathways are analyzed at the functional level, the painted turtle may offer important insights into the management of a number of human health disorders