3,419 research outputs found
Cardiac evaluation of young athletes: Time for a risk-based approach?
Pre-participation cardiovascular screening (PPCS) is recommended by several scientific and sporting organizations on the premise that early detection of cardiac disease provides a platform for individualized risk assessment and management; which has been proven to lower mortality rates for certain conditions associated with sudden cardiac arrest (SCA) and sudden cardiac death (SCD). What constitutes the most effective strategy for PPCS of young athletes remains a topic of considerable debate. The addition of the electrocardiogram (ECG) to the medical history and physical examination undoubtedly enhances early detection of disease, which meets the primary objective of PPCS. The benefit of enhanced sensitivity must be carefully balanced against the risk of potential harm through increased false-positive findings, costly downstream investigations, and unnecessary restriction/disqualification from competitive sports. To mitigate this risk, it is essential that ECG-based PPCS programs are implemented by institutions with a strong infrastructure and by physicians appropriately trained in modern ECG standards with adequate cardiology resources to guide downstream investigations. While PPCS is compulsory for most competitive athletes, the current debate surrounding ECG-based programs exists in a binary form; whereby ECG screening is mandated for all competitive athletes or none at all. This polarized approach fails to consider individualized patient risk and the available sports cardiology resources. The limitations of a uniform approach are highlighted by evolving data, which suggest that athletes display a differential risk profile for SCA/SCD, which is influenced by age, sex, ethnicity, sporting discipline, and standard of play. Evaluation of the etiology of SCA/SCD within high-risk populations reveals a disproportionately higher prevalence of ECG-detectable conditions. Selective ECG screening using a risk-based approach may, therefore, offer a more cost-effective and feasible approach to PPCS in the setting of limited sports cardiology resources, although this approach is not without important ethical considerations
All Politics Is Global: Explaining International Regulatory Regimes
Has globalization diluted the power of national governments to regulate their own economies? Are international governmental and nongovernmental organizations weakening the hold of nation-states on global regulatory agendas? Many observers think so. But in All Politics Is Global , Daniel Drezner argues that this view is wrong. Despite globalization, states--especially the great powers--still dominate international regulatory regimes, and the regulatory goals of states are driven by their domestic interests. As Drezner shows, state size still matters. The great powers--the United States and the European Union--remain the key players in writing global regulations, and their power is due to the size of their internal economic markets. If they agree, there will be effective global governance. If they don't agree, governance will be fragmented or ineffective. And, paradoxically, the most powerful sources of great-power preferences are the least globalized elements of their economies. Testing this revisionist model of global regulatory governance on an unusually wide variety of cases, including the Internet, finance, genetically modified organisms, and intellectual property rights, Drezner shows why there is such disparity in the strength of international regulations.globalization, politics, governance, international regulatory regimes, nongovernmental organizations, states, great powers
Abnormal electrocardiographic findings in athletes: Correlation with intensity of sport and level of competition.
INTRODUCTION: Athletes can exhibit abnormal electrocardiogram (ECG) phenotypes that require further evaluation prior to competition. These are apparently more prevalent in high-intensity endurance sports. The purpose of this study was to assess the association between ECG findings in athletes and intensity of sport and level of competition. METHODS: A cohort of 3423 competitive athletes had their ECGs assessed according to the Seattle criteria (SC). The presence of abnormal ECGs was correlated with: (1) intensity of sport (low/moderate vs. at least one high static or dynamic component); (2) competitive level (regional vs. national/international); (3) training volume (≤20 vs. >20 hours/week); (4) type of sport (high dynamic vs. high static component). The same endpoints were studied according to the 'Refined Criteria' (RC). RESULTS: Abnormal ECGs according to the SC were present in 225 (6.6%) athletes, more frequently in those involved in high-intensity sports (8.0% vs. 5.4%; p=0.002), particularly in dynamic sports, and competing at national/international level (7.1% vs. 4.9%; p=0.028). Training volume was not significantly associated with abnormal ECGs. By multivariate analysis, high-intensity sport (OR 1.55, 1.18-2.03; p=0.002) and national/international level (OR 1.50, 95% CI 1.04-2.14; p=0.027) were independent predictors of abnormal ECGs, and these variables, when combined, doubled the prevalence of this finding. According to the RC, abnormal ECGs decreased to 103 (3.0%), but were also more frequent in high-intensity sports (4.2% vs. 2.0%; p<0.001). CONCLUSIONS: There is a positive correlation between higher intensity of sports and increased prevalence of ECG abnormalities. This relationship persists with the use of more restrictive criteria for ECG interpretation, although the number of abnormal ECGs is lower
The Viscosity of Global Governance
Streaming video requires RealPlayer to view.The University Archives has determined that this item is of continuing value to OSU's history.Daniel Drezner is associate professor of international politics at the Fletcher
School of Law and Diplomacy at Tufts University. His recent paper suggests that issue linkage and organizational reputation can increase the
viscosity of global governance in the short run. The barriers to forum-shopping are
not constant over time, however; in the long run, there is little viscosity in global
governance structures.Ohio State University. Mershon Center for International Security StudiesEvent webpage, streaming video, photo
A review of competitive facility location in the plane
In this paper, we review competitive location models. Retail facilities operate in a competitive environment with an objective of profit and market share maximization. These facilities are different from each other in their overall attractiveness to consumers. The basic problem is the optimal location of one or more new facilities in a market where competition already exists or will exist in the future. Extensions to the models include an analysis of the optimal allocation of a budget among new facilities and their best locations, modeling location under conditions of uncertainty and future competition, incorporating the concept of a threshold in competitive location, modeling lost demand, and minimizing cannibalization
The continuous p-centre problem: An investigation into variable neighbourhood search with memory
A VNS-based heuristic using both a facility as well as a customer type neighbourhood structure is proposed to solve the p-centre problem in the continuous space. Simple but effective enhancements to the original Elzinga-Hearn algorithm as well as a powerful ‘locate-allocate’ local search used within VNS are proposed. In addition, efficient implementations in both neighbourhood structures are presented. A learning scheme is also embedded into the search to produce a new variant of VNS that uses memory. The effect of incorporating strong intensification within the local search via a VND type structure is also explored with interesting results. Empirical results, based on several existing data set (TSP-Lib) with various values of p, show that the proposed VNS implementations outperform both a multi-start heuristic and the discrete-based optimal approach that use the same local search
A modified Kolmogorov-Smirnov test for normality
In this paper we propose an improvement of the Kolmogorov-Smirnov test for normality. In the current implementation of the Kolmogorov-Smirnov test, a sample is compared with a normal distribution where the sample mean and the sample variance are used as parameters of the distribution. We propose to select the mean and variance of the normal distribution that provide the closest fit to the data. This is like shifting and stretching the reference normal distribution so that it fits the data in the best possible way. If this shifting and stretching does not lead to an acceptable fit, the data is probably not normal. We also introduce a fast easily implementable algorithm for the proposed test. A study of the power of the proposed test indicates that the test is able to discriminate between the normal distribution and distributions such as uniform, bi-modal, beta, exponential and log-normal that are different in shape, but has a relatively lower power against the student t-distribution that is similar in shape to the normal distribution. In model settings, the former distinction is typically more important to make than the latter distinction. We demonstrate the practical significance of the proposed test with several simulated examples.Closest fit; Kolmogorov-Smirnov; Normal distribution
Assessment of genetic diversity of wheat genotypes using microsatellite markers
Background and Purpose: Genetic diversity is the material basis for crop improvement. In this study, genetic diversity of 30wheat genotypeswas evaluated at theDNAlevel using 24 simple sequence repeat (SSRs) markers. Materials and Methods: DNA extraction was performed according to the modified CTAB-method. Microsatellite analysis was performed using fluorescent fragment detection on a LI-COR 4200 DNA. Results and Discussion: The number of alleles per locus ranged from 1 to 14 with an average number of 8.44 alleles per locus. The highest number of alleles per locus was detected in the genome A with 7.2, compared to 5.9 and 5.0 for genomes B and D, respectively. The highest number of alleles was recorded at chromosome 7 (9.5), while the lowest number of alleles was detected at chromosomes 3 and 4 (5.0 and 5.3). The smallest genetic distance characterized genotypes Super Zitarka and Zitarka, Tena and Osjecanka, Tena and Bezostaja, Lela and Toras, Janica and Alka, Felix and Seka.Genotypes Pipi and Courtot showed the least genetic similiarities with rest of the genotypes. Conclusions: The identification of genetic diversity should be a good tool of selecting genotypes in breeding programs
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