The athletic characteristics of Olympic sports to assist anti-doping strategies.

The determinants of success in Olympic Games competition are specific to the athletic demands of the sporting event. A global evaluation to quantify the athletic demands across the spectrum of the Olympic Games sport events has not previously been conducted. Thus far, the interpretation and the comparison of sport physiological characteristics within anti-doping organisations (ADOs) risk assessments remains subjective without a standardised framework. Despite its subjective assessment, this information is a key component of any anti-doping programme. Sport characteristics inevitably influence the type of substances and/or methods used for doping purposes and should be captured through a comprehensive analysis. Seven applied sport scientists independently conducted an assessment to quantify the athletic demands across six preselected athletic variables. A principal component analysis was performed on the results of the panel's quantitative assessment for 160 Olympic sport events. Sport events were clustered using the Hierarchical Density Based Spatial Clustering of Applications with Noise (HDBSCAN) algorithm. The HDBSCAN identified 19 independent cluster groups; 36 sport events remained statistically unassigned to a cluster group representing unique and event-specific athletic demands. This investigation provides guidance to the anti-doping community to assist in the development of the sport specific physiology component of the risk assessment for Olympic Games disciplines. The dominant athletic characteristics to excel in each of these individual events will highlight areas of how athletes may strive to gain a competitive advantage through doping strategies, and inform the development of an effective and proportionate allocation of testing resources.

Quantifying expert opinion with discrete choice models: Invasive elodea's influence on Alaska salmonids.

Scientific evidence should inform environmental policy, but rapid environmental change brings high ecological uncertainty and associated barriers to the science-management dialogue. Biological invasions of aquatic plants are a worldwide problem with uncertain ecological and economic consequences. We demonstrate that the discrete choice method (DCM) can serve as a structured expert elicitation alternative to quantify expert opinion across a range of possible but uncertain environmental outcomes. DCM is widely applied in the social sciences to better understand and predict human preferences and trade-offs. Here we apply it to Alaska's first submersed invasive aquatic freshwater plant, Elodea spp. (elodea), and its unknown effects on salmonids. While little is known about interactions between elodea and salmonids, ecological research suggests that aquatic plant invasions can have positive and negative, as well as direct and indirect, effects on fish. We use DCM to design hypothetical salmonid habitat scenarios describing elodea's possible effect on critical environmental conditions for salmonids: prey abundance, dissolved oxygen, and vegetation cover. We then observe how experts choose between scenarios that they believe could support persistent salmonid populations in elodea-invaded salmonid habitat. We quantify the relative importance of habitat characteristics that influence expert choice and investigate how experts trade off between habitat characteristics. We take advantage of Bayesian techniques to estimate discrete choice models for individual experts and to simulate expert opinion for specific environmental management situations. We discuss possible applications and advantages of the DCM approach for expert elicitation in the ecological context. We end with methodological questions for future research.

Factors influencing the development of antibiotic associated diarrhea in ED patients discharged home: risk of administering IV antibiotics.

OBJECTIVE: Antibiotic-associated diarrhea (AAD) and Clostridium difficile infection (CDI) are well-known outcomes from antibiotic administration. Because emergency department (ED) visits frequently result in antibiotic use, we evaluated the frequency of AAD/CDI in adults treated and discharged home with new prescriptions for antibiotics to identify risk factors for acquiring AAD/CDI. METHODS: This prospective multicenter cohort study enrolled adult patients who received antibiotics in the ED and were discharged with a new prescription for antibiotics. Antibiotic-associated diarrhea was defined as 3 or more loose stools for 2 days or more within 30 days of starting the antibiotic. C difficile infection was defined by the detection of toxin A or B within this same period. We used multivariate logistic regression to assess predictors of developing AAD. RESULTS: We enrolled and followed 247 patients; 45 (18%) developed AAD, and 2 (1%) developed CDI. Patients who received intravenous (IV) antibiotics in the ED were more likely to develop AAD/CDI than patients who did not: 25.7% (95% confidence interval [CI], 17.4-34.0) vs 12.3% (95% CI, 6.8-17.9). Intravenous antibiotics had adjusted odds ratio of 2.73 (95% CI, 1.38-5.43), and Hispanic ethnicity had adjusted odds ratio of 3.04 (95% CI, 1.40-6.58). Both patients with CDI had received IV doses of broad-spectrum antibiotics. CONCLUSION: Intravenous antibiotic therapy administered to ED patients before discharge was associated with higher rates of AAD and with 2 cases of CDI. Care should be taken when deciding to use broad-spectrum IV antibiotics to treat ED patients before discharge home.

A randomized, controlled trial of oral versus intravenous fluids for lowering blood glucose in emergency department patients with hyperglycemia.

OBJECTIVES: Blood glucose can be lowered via insulin and/or fluid administration. Insulin, although efficacious, can cause hypoglycemia and hypokalemia. Fluids do not cause hypoglycemia or hypokalemia, but the most effective route of fluid administration has not been well described. This study compared the efficacy and safety of oral versus intravenous fluids for reducing blood glucose in patients with hyperglycemia. METHODS: We conducted a prospective, nonblinded, randomized, controlled trial. Inclusion criteria were blood glucose > 13.9 mmol/L, age > 18 years, and ability to tolerate oral fluids. Subjects were excluded for critical illness, contraindication to fluids, and/or hyperglycemia therapy prior to enrolment. Subjects were randomized to receive oral bottled water or intravenous normal saline (maximum 2 L) over 2 hours. The primary outcome of interest was a change in blood glucose at 2 hours across treatment arms. RESULTS: The 48 subjects were randomized. Baseline blood glucose levels and total amount of fluid received were similar between the two groups. The mean decrease in blood glucose at 2 hours was similar for both treatment arms: a mean decrease of 3.4 mmol/L (20.2 mmol/L to 16.8 mmol/L) in the oral fluid group versus a mean decrease of 4.0 mmol/L (19.7 mmol/L to 15.7 mmol/L) in the intravenous fluid group. The mean difference between groups was -0.6 mmol/L (95% confidence interval -2.3-1.2; p  =  0.51). No adverse events were observed in either group. CONCLUSION: In this unblinded randomized trial, oral and intravenous fluids were equally efficacious in lowering blood glucose levels in stable hyperglycemic patients and no adverse events were noted. Physicians should be mindful that, although similar, the reduction in blood glucose was modest in both groups.

Minimum viable populations: is there a 'magic number' for conservation practitioners?

Establishing species conservation priorities and recovery goals is often enhanced by extinction risk estimates. The need to set goals, even in data-deficient situations, has prompted researchers to ask whether general guidelines could replace individual estimates of extinction risk. To inform conservation policy, recent studies have revived the concept of the minimum viable population (MVP), the population size required to provide some specified probability of persistence for a given period of time. These studies conclude that long-term persistence requires ≥5000 adult individuals, an MVP threshold that is unaffected by taxonomy, life history or environmental conditions. Here, we re-evaluate this suggestion. We find that neither data nor theory supports its general applicability, raising questions about the utility of MVPs for conservation planning.

Design to monitor trend in abundance and presence of American beaver (Castor canadensis) at the national forest scale.

Wildlife conservationists design monitoring programs to assess population dynamics, project future population states, and evaluate the impacts of management actions on populations. Because agency mandates and conservation laws call for monitoring data to elicit management responses, it is imperative to design programs that match the administrative scale for which management decisions are made. We describe a program to monitor population trends in American beaver (Castor canadensis) on the US Department of Agriculture, Black Hills National Forest (BHNF) in southwestern South Dakota and northeastern Wyoming, USA. Beaver have been designated as a management indicator species on the BHNF because of their association with riparian and aquatic habitats and its status as a keystone species. We designed our program to monitor the density of beaver food caches (abundance) within sampling units with beaver and the proportion of sampling units with beavers present at the scale of a national forest. We designated watersheds as sampling units in a stratified random sampling design that we developed based on habitat modeling results. Habitat modeling indicated that the most suitable beaver habitat was near perennial water, near aspen (Populus tremuloides) and willow (Salix spp.), and in low gradient streams at lower elevations. Results from the initial monitoring period in October 2007 allowed us to assess costs and logistical considerations, validate our habitat model, and conduct power analyses to assess whether our sampling design could detect the level of declines in beaver stated in the monitoring objectives. Beaver food caches were located in 20 of 52 sampled watersheds. Monitoring 20 to 25 watersheds with beaver should provide sufficient power to detect 15-40% declines in the beaver food cache index as well as a twofold decline in the odds of beaver being present in watersheds. Indices of abundance, such as the beaver food cache index, provide a practical measure of population status to conduct long-term monitoring across broad landscapes such as national forests.

A comparison of 2 protocols to detect intimate partner violence.

PURPOSE: Intimate partner violence (IPV) frequently results in maxillofacial injuries. The purpose of this study is to compare 2 protocols to identify women who self-report IPV-related injuries. MATERIALS AND METHODS: Using a cross-sectional study design, we enrolled a sample of injured women who presented to the emergency department (ED) for evaluation and treatment. The predictor variable was the protocol used to identify injury etiology, that is, an innovative diagnostic protocol (DP) or the ED's standard operating procedure (SOP). The outcome variable was self-reported injury etiology categorized as IPV or other. Descriptive and bivariate statistics were computed. Sensitivity, specificity, positive predictive value, negative predictive value, and odds ratios were computed (with P < or = .05 being considered statistically significant). RESULTS: The sample was composed of 286 women with a mean age of 45.8 years. The self-reported prevalence of IPV-related injuries was 11.5% and 5% for the DP and SOP, respectively (P = .03). The diagnostic statistics for the DP and SOP, respectively, were as follows: sensitivities, 94% and 50%; specificities, 76% and 95%; positive predictive values, 34% and 50%; and negative predictive values, 98% and 95%. In the adjusted model the women evaluated with the DP had a 38-fold increased likelihood of reporting IPV (P < .01) when compared with the SOP. CONCLUSIONS: These results suggest that the proposed DP is associated with an increased frequency of self-reported IPV-related injuries when compared with the ED's SOP.