The biomechanical design and analysis of gymnastics training equipment

Training aids can play an important role in the training of athletes, but only if they assist in the learning of correct technique. The design of a training aid differs considerably from the design of other products because it is crucial that the mechanisms used in learning a skill must be taken into consideration. Research has shown that this can be achieved by: encouraging specific motor skills, providing feedback, providing support in a safe environment, permitting repetition, permitting progressive learning, or by providing some combination of these. For this to be possible an in-depth understanding of the biomechanical requirements of the sporting activity is essential. A study was carried out to determine the fundamental requirements of a training aid, and to then design and build two working prototype gymnastics training aids. Elite training sessions were observed and High Performance coaches were interviewed to establish the skills that required a training aid and the customer requirements for such a device. On the basis of this information two contrasting gymnastics skills were chosen. The first was a handstand on the rings, a complex motor control skill requiring the gymnast to balance on two moving pendulums, requested by 100% of the coaches interviewed. The second skill was a backward handspring, often the first backward dynamic skill most gymnasts will learn, requested by 89% of the coaches interviewed. The training aids were required to simplify the learning of the skill, whilst still utilising correct technique. The backward handspring aid was also required to effectively support the gymnast but not obstruct a good performance. A biomechanical analysis of each skill was carried out in order to inform the design of suitable training aids. The aids were designed and manufactured in accordance with British Standards, and were then biomechanically assessed to ensure that they correctly aided the learning of the skills. In order to assess the aids: displacement, force and muscle activation data were collected and were used to compare the gymnastics skills with and without the aids. The data showed that the training aids replicated the correct biomechanical requirements of the actual skills: the handstand aid was shown to utilise the same control mechanism as was observed on the rings, and the backward handspring aid permitted a unobstructed good performance and assisted in the learning of the skills with correct technique. Both aids were also demonstrated to out-perform any of the existing training aids.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Scattering in InAs/GaSb Coupled Quantum Wells as a Probe of Higher Order Subband Hybridisation

We have performed a detailed investigation into the inter-subband scattering within InAs/GaSb coupled quantum wells in the electron dominated regime. By considering the carrier mobilities and the quantum lifetime as a function of carrier density, we find that the occupation of higher order electron-like subbands are inhibited by anticrossing with the hole subbands. We also find that, by applying a gate bias to the GaSb layer, we are able to move the electron-hole anticrossing point in energy, modulating the electron-like states that should be localised within the InAs layer

The uniting of Europe and the foundation of EU studies: revisiting the neofunctionalism of Ernst B. Haas

This article suggests that the neofunctionalist theoretical legacy left by Ernst B. Haas is somewhat richer and more prescient than many contemporary discussants allow. The article develops an argument for routine and detailed re-reading of the corpus of neofunctionalist work (and that of Haas in particular), not only to disabuse contemporary students and scholars of the normally static and stylized reading that discussion of the theory provokes, but also to suggest that the conceptual repertoire of neofunctionalism is able to speak directly to current EU studies and comparative regionalism. Neofunctionalism is situated in its social scientific context before the theory's supposed erroneous reliance on the concept of 'spillover' is discussed critically. A case is then made for viewing Haas's neofunctionalism as a dynamic theory that not only corresponded to established social scientific norms, but did so in ways that were consistent with disciplinary openness and pluralism

Spin-valve Josephson junctions with perpendicular magnetic anisotropy for cryogenic memory

We demonstrate a Josephson junction with a weak link containing two ferromagnets with perpendicular magnetic anisotropy and independent switching fields in which the critical current can be set by the mutual orientation of the two layers. Such pseudospin-valve Josephson junctions are a candidate cryogenic memory in an all superconducting computational scheme. Here, we use Pt/Co/Pt/CoB/Pt as the weak link of the junction with dCo=0.6 nm, dCoB=0.3 nm, and dPt=5 nm and obtain a 60% change in the critical current for the two magnetization configurations of the pseudospin-valve. Ferromagnets with perpendicular magnetic anisotropy have advantages over magnetization in-plane systems, which have been exclusively considered at this point, as, in principle, the magnetization and magnetic switching of layers in the junction should not affect the in-plane magnetic flux

A Comprehensive Review of Prehospital and In-Hospital Delay Times in Acute Stroke Care

The purpose of this study was to systematically review and summarize prehospital and in-hospital stroke evaluation and treatment delay times. We identified 123 unique peer-reviewed studies published from 1981 to 2007 of prehospital and in-hospital delay time for evaluation and treatment of patients with stroke, transient ischemic attack, or stroke-like symptoms. Based on studies of 65 different population groups, the weighted Poisson regression indicated a 6.0% annual decline (p<0.001) in hours/year for prehospital delay, defined from symptom onset to emergency department (ED) arrival. For in-hospital delay, the weighted Poisson regression models indicated no meaningful changes in delay time from ED arrival to ED evaluation (3.1%, p=0.49 based on 12 population groups). There was a 10.2% annual decline in hours/year from ED arrival to neurology evaluation or notification (p=0.23 based on 16 population groups) and a 10.7% annual decline in hours/year for delay time from ED arrival to initiation of computed tomography (p=0.11 based on 23 population groups). Only one study reported on times from arrival to computed tomography scan interpretation, two studies on arrival to drug administration, and no studies on arrival to transfer to an in-patient setting, precluding generalizations. Prehospital delay continues to contribute the largest proportion of delay time. The next decade provides opportunities to establish more effective community based interventions worldwide. It will be crucial to have effective stroke surveillance systems in place to better understand and improve both prehospital and in-hospital delays for acute stroke care

Compliance With Acute Stroke Care Quality Measures in Hospitals With and Without Primary Stroke Center Certification: The North Carolina Stroke Care Collaborative

BackgroundOrganized stroke care is associated with improved outcomes. Data are limited on differences in changes in the quality of acute stroke care at The Joint Commission–certified Primary Stroke Centers (PSCs) versus non‐PSCs over time.Methods and ResultsWe compared compliance with the Joint Commission's 10 acute stroke care performance measures and defect‐free care in PSCs and non‐PSCs participating in the Registry of the North Carolina Stroke Care Collaborative from January 2005 through February 2010. We included 29 654 cases presenting at 47 hospitals—10 PSCs, 8 preparing for certification, and 29 non‐PSCs—representing 43% of North Carolina's non–Veterans Affairs, acute care hospitals. Using a non‐PSC referent, odds ratios and 95% CIs were calculated using logistic regression and generalized estimating equations accounting for clustering of cases within hospitals. Time trends were presented graphically using simple linear regression. Performance measure compliance increased for all measures for all 3 groups in 2005–2010, with the exception of discharge on antithrombotics, which remained consistently high. PSCs and hospitals preparing for certification had better compliance with all but 2 performance measures compared with non‐PSCs (each P<0.01). Defect‐free care was delivered most consistently at hospitals preparing for certification (52.8%), followed by PSCs (45.0%) and non‐PSCs (21.9%). Between 2005 and 2010, PSCs and hospitals preparing for certification had a higher average annual percent increase in the provision of defect‐free care (P=0.01 and 0.04, respectively) compared with non‐PSCs.ConclusionsPSC certification is associated with an overall improvement in the quality of stroke care in North Carolina; however, room for improvement remains

Role of BMI in the Association of the TCF7L2 rs7903146 Variant with Coronary Heart Disease: The Atherosclerosis Risk in Communities (ARIC) Study

We examined the association of variation in the type 2 diabetes risk-conferring TCF7L2 gene with the risk of incident coronary heart disease (CHD) among the lean, overweight, and obese members of the Atherosclerosis Risk in Communities (ARIC) Study cohort. Cox proportional hazard regression analyses were performed using a general model, with the major homozygote as the reference category. For 9,865 whites, a significant increase in the risk of CHD was seen only among lean ( BMI < 25 kg/m2) individuals homozygous for the T allele of the TCF7L2 rs7903146 gene risk variant (hazard ratio 1.42; 95% CI 1.03,1.97; P = .01). No association was found among 3,631 blacks, regardless of BMI status. An attenuated hazard ratio was observed among the nondiabetic ARIC cohort members. This study suggests that body mass modifies the association of the TCF7L2 rs7903146 T allele with CHD risk

Carotid Artery Wall Thickness and Risk of Stroke Subtypes: The Atherosclerosis Risk in Communities Study

Understanding associations of carotid atherosclerosis with stroke subtypes may contribute to more effective prevention of stroke

Challenges of Ascertaining National Trends in the Incidence of Coronary Heart Disease in the United States

Despite major therapeutic advances, the public health burden associated with coronary heart disease (CHD) remains enormous with approximately 525 000 people predicted to have a new myocardial infarction (MI) in 2013, ≈15.4 million estimated to be living with CHD in 2013, and ≈1 346 000 peopl

Diabetes nutrition therapy and dietary intake among individuals with Type 1 diabetes in China

To describe the contribution of diabetes nutrition therapy to disease self-management among individuals with Type 1 diabetes mellitus in China and to estimate the association of diabetes nutrition therapy with dietary intake