1,136 research outputs found
New problems, new challenges: embracing innovative approaches to sport research
New problems, new challenges: embracing innovative approaches to sport researc
Doping in sport: Whose problem is it?
In the last few years there has been a significant increase in the number and scope of social science research into doping in sport. However, despite this apparent progress, the field remains a disparate body of work and lacks both direction and leadership. Whilst sport management is a discipline that is well suited to provide such leadership, scholarly research into this controversial topic has not been published widely in sport management
journals. This special issue redresses this gap by bringing together a range of scholarly
articles that represent a variety of perspectives by authors from North America, Europe and Australia. The issues and challenges covered are varied, but each paper brings a common theme: the implications for the management of doping in sport. The six papers in this Special Issue of Sport Management Review are a significant addition to the slowly growing body of sport management scholarly work on doping in sport. It is hoped that future research will be prompted with this Special Issue and the discipline of sport management will recognize and respond to the challenges presented by doping
Nonlinear analysis of the heartbeats in public patient ECGs using an automated PD2i algorithm for risk stratification of arrhythmic death
Heart rate variability (HRV) reflects both cardiac autonomic function and risk of arrhythmic death (AD). Reduced indices of HRV based on linear stochastic models are independent risk factors for AD in post-myocardial infarct cohorts. Indices based on nonlinear deterministic models have a significantly higher sensitivity and specificity for predicting AD in retrospective data. A need exists for nonlinear analytic software easily used by a medical technician. In the current study, an automated nonlinear algorithm, the time-dependent point correlation dimension (PD2i), was evaluated. The electrocardiogram (ECG) data were provided through an National Institutes of Health-sponsored internet archive (PhysioBank) and consisted of all 22 malignant arrhythmia ECG files (VF/VT) and 22 randomly selected arrhythmia files as the controls. The results were blindly calculated by automated software (Vicor 2.0, Vicor Technologies, Inc., Boca Raton, FL) and showed all analyzable VF/VT files had PD2i < 1.4 and all analyzable controls had PD2i > 1.4. Five VF/VT and six controls were excluded because surrogate testing showed the RR-intervals to contain noise, possibly resulting from the low digitization rate of the ECGs. The sensitivity was 100%, specificity 85%, relative risk > 100; p < 0.01, power > 90%. Thus, automated heartbeat analysis by the time-dependent nonlinear PD2i-algorithm can accurately stratify risk of AD in public data made available for competitive testing of algorithms
The final frontier of anti-doping: a study of athletes who have committed doping violations
Although the use of banned drugs in sport is not a new phenomenon, little is known about
the experiences and perceptions of athletes who have committed anti-doping rule
violations. This study qualitatively explored the experiences of 18 athletes (from the
sports of bodybuilding, powerlifting, cricket, sprint kayak, rugby league, and swimming)
who had committed anti-doping violations. Themes explored included motivations for
initiating and maintaining doping, the psychology of doping, deterrents to doping, and
views on current anti-doping policy. In most cases doping had started early in their
careers. The perceived culture of the sport was considered central to the ‘normalization’ of
doping, particularly in bodybuilding. When explaining their decision to dope, athletes
engaged in processes or moral disengagement (including advantageous comparison,
minimizing consequences and diffusion of responsibility). Ironically, moral arguments
were perceived as the most effective deterrents to doping. Findings are discussed in
relation to the difficulties in establishing credible deterrents and suggestions for the future
development of anti-doping policy
Sidelined: employment relations in professional sports
Sidelined: employment relations in professional sport
Corruption in sport: understanding the complexity of corruption
Corruption in sport: understanding the complexity of corruptio
An Empirical Non-TNT Approach to Launch Vehicle Explosion Modeling
In an effort to increase crew survivability from catastrophic explosions of Launch Vehicles (LV), a study was conducted to determine the best method for predicting LV explosion environments in the near field. After reviewing such methods as TNT equivalence, Vapor Cloud Explosion (VCE) theory, and Computational Fluid Dynamics (CFD), it was determined that the best approach for this study was to assemble all available empirical data from full scale launch vehicle explosion tests and accidents. Approximately 25 accidents or full-scale tests were found that had some amount of measured blast wave, thermal, or fragment explosion environment characteristics. Blast wave overpressure was found to be much lower in the near field than predicted by most TNT equivalence methods. Additionally, fragments tended to be larger, fewer, and slower than expected if the driving force was from a high explosive type event. In light of these discoveries, a simple model for cryogenic rocket explosions is presented. Predictions from this model encompass all known applicable full scale launch vehicle explosion data. Finally, a brief description of on-going analysis and testing to further refine the launch vehicle explosion environment is discussed
Structure and triclustering in Ba-Al-O glass
Glass-forming ability in the (BaO) x(Al 2O 3) 1-x system (0≤x≤1) was investigated by using the containerless aerodynamic levitation and laser-heating method. The main glass-forming region was found to occur for 0.40(2) ≤x≤ 0.48(2), where there is insufficient oxygen to form an ideal network of corner-sharing AlO 4 tetrahedra in which the oxygen atoms are twofold coordinated, with another narrow glass-forming region at x = 0.62(2) around the eutectic composition. The glass corresponding to x = 0.4 was chosen for further investigation by using both neutron and x-ray diffraction, and a detailed atomistic model was built by applying a combination of molecular dynamics and reverse Monte Carlo methods. The results show a network structure based predominantly on corner-sharing tetrahedral AlO 4 motifs in which triclusters (OAl 3 units formed by three tetrahedral Al atoms sharing a common vertex) play an integral part, with as many as 21% of the oxygen atoms involved in these configurations. The barium ions bind to an average of 7.4 O atoms, most of which are twofold-coordinated bridging oxygen atoms. The larger size of barium compared to calcium narrows the range of glass-forming compositions in alkaline-earth aluminates such that the main glass-forming range corresponds to a regime in which an oxygen-deficient Al-O network is stabilized by the formation of triclusters
Saquinavir Inhibits the malaria parasite's chloroquine resistance transporter
The antiretroviral protease inhibitors (APIs) ritonavir, saquinavir, and lopinavir, used to treat HIV infection, inhibit the growth of Plasmodium falciparum at clinically relevant concentrations. Moreover, it has been reported that these APIs potentiate the activity of chloroquine (CQ) against this parasite in vitro. The mechanism underlying this effect is not understood, but the degree of chemosensitization varies between the different APIs and, with the exception of ritonavir, appears to be dependent on the parasite exhibiting a CQ-resistant phenotype. Here we report a study of the role of the P. falciparum chloroquine resistance transporter (PfCRT) in the interaction between CQ and APIs, using transgenic parasites expressing different PfCRT alleles and using the Xenopus laevis oocyte system for the heterologous expression of PfCRT. Our data demonstrate that saquinavir behaves as a CQ resistance reverser and that this explains, at least in part, its ability to enhance the effects of CQ in CQ-resistant P. falciparum parasites. Copyrigh
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