1,781 research outputs found
POPULATION-SPECIFIC RECREATION DEMAND MODELS AND THE CONSEQUENCES OF POOLING SAMPLE DATA
This paper considers the implications of different geographical population definitions in analysis of demand for wildlife recreation. Demand functions for fishing, small game hunting, big game hunting, and wildlife enjoyment are estimated for individual Southeastern states and also for a pooled sample of all the states. Statistically significant differences between the state and regional estimates of the variable cost coefficient exist in 18 of the 40 cases. Consumer surplus values derived from state cost coefficients can differ greatly from values derived from pooled coefficients.Resource /Energy Economics and Policy,
Conversing Life: An Autoethnographic Construction
This autoethnography is a constructed account of a co-exploration into the nature and effects of a longitudinal dyadic conversation process from a relational constructionist perspective. The conversations, between me as participant autoethnographer and a co-participant, aimed at maximising personal learning for both. Through co-created contexts of mutual engagement and respectful presence, we were able to focus our learning on the spontaneous process and content of the conversations. The qualitative data were sampled purposively from diary entries summarizing the conversations which spanned a period of five years. The data were analysed into themes and together, with selected illustrative examples of significant conversational moments, were woven into an autoethnography that attempts to convey the embodied and systemic learning that emerged from these conversations
Scattering of a Baseball by a Bat
A ball can be hit faster if it is projected without spin but it can be hit
farther if it is projected with backspin. Measurements are presented in this
paper of the tradeoff between speed and spin for a baseball impacting a
baseball bat. The results are inconsistent with a collision model in which the
ball rolls off the bat and instead imply tangential compliance in the ball, the
bat, or both. If the results are extrapolated to the higher speeds that are
typical of the game of baseball, they suggest that a curveball can be hit with
greater backspin than a fastball, but by an amount that is less than would be
the case in the absence of tangential compliance.Comment: Accepted for publication in American Journal of Physic
SURVEYING FOR RANAVIRUS IN GREEN FROGS (LITHOBATES CLAMITANS) AT FIVE LOCATIONS IN INDIANA
Ranaviruses are an emerging pathogen within the United States that infects amphibians, reptiles, and fish. A Frog Virus 3-like (FV3) ranavirus has been detected at only two locations in Indiana; however, there have been few attempts to broadly sample for ranaviruses to determine their distribution across the state. This knowledge is necessary for the continued management and conservation of native amphibian populations. Our objective was to assess the occurrence of FV3-like ranaviruses in larval Green Frog (Lithobates clamitans) populations at five sites located in different regions of Indiana. Tissue samples were collected from 166 individuals and were assayed using both conventional and qPCR methods. We did not detect the presence of any FV3-like ranaviruses at any of the five sites with either PCR method, suggesting the possibility that at these sites, FV3-like ranaviruses may not be present. However, continued sampling should be carried out to monitor the status of the presence of ranaviruses in this portion of the Midwest
Space Shuttle Crawler Transporter Sound Attenuation Study
The crawler transporter (CT) is the world's largest tracked vehicle known, weighing 6 million pounds with a length of 131 feet and a width of 113 feet. The Kennedy Space Center (KSC) has two CTs that were designed and built for the Apollo program in the 1960's, maintained and retrofitted for use in the Space Shuttle program. As a key element of the Space Shuttle ground systems, the crawler transports the entire 12-million-pound stack comprising the orbiter, the mobile launch platform (MLP), the external tank (ET), and the solid rocket boosters (SRB) from the Vehicle Assembly Building (VAB) to the launch pad. This rollout, constituting a 3.5-5.0-mile journey at a top speed of 0.9 miles-per-hour, requires over 8 hours to reach either Launch Complex 39A or B. This activity is only a prelude to the spectacle of sound and fury of the Space Shuttle launch to orbit in less than 10 minutes and traveling at orbital velocities of Mach 24. This paper summarizes preliminary results from the Crawler Transporter Sound Attenuation Study, encompassing test and engineering analysis of significant sound sources to measure and record full frequency spectrum and intensity of the various noise sources and to analyze the conditions of vibration. Additionally, data such as ventilation criteria, plus operational procedures were considered to provide a comprehensive noise suppression design for implementation. To date, sound attenuation study and results on Crawler 2 have shown significant noise reductions ranging from 5 to 24 dBA
Key dating features for timber-framed dwellings in Surrey
This article is made available through the Brunel Open Access Publishing Fund. Copyright @ The Vernacular Architecture Group 2013. MORE OpenChoice articles are open access and distributed under the terms of the Creative Commons Attribution License 3.0.The main component of the Surrey Dendrochronology Project is the accurate dating of 177 ‘dwellings’, nearly all by tree-ring analysis. The dates are used to establish date ranges for 52 ‘key features’, which cover many aspects of timber-framing from building type to details of carpentry. It is shown that changes of method and fashion were in many cases surprisingly rapid, almost abrupt in historical terms. Previous dating criteria for timber-framed dwellings in the county have been refined and new criteria introduced. Clusters of change from the 1440s and the 1540s are shown and some possible historical links suggested.The Heritage Lottery Fund, the Domestic Buildings Research Group (Surrey), the Surrey Archaeological Society and the historical societies of Charlwood, Farnham and Nutfield
Exercise-based cardiac rehabilitation for coronary heart disease
PublishedReviewThis review is published as a Cochrane Review in the Cochrane Database of Systematic Reviews 2016, Issue 1. Cochrane Reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and the Cochrane Database of Systematic Reviews should be consulted for the most recent version of the Review.Background Coronary heart disease (CHD) is the single most common cause of death globally. However, with falling CHD mortality rates, an increasing number of people live with CHD and may need support to manage their symptoms and prognosis. Exercise-based cardiac rehabilitation (CR) aims to improve the health and outcomes of people with CHD. This is an update of a Cochrane systematic review previously published in 2011. Objectives To assess the effectiveness and cost-effectiveness of exercise-based CR (exercise training alone or in combination with psychosocial or educational interventions) compared with usual care on mortality, morbidity and HRQL in patients with CHD. To explore the potential study level predictors of the effectiveness of exercise-based CR in patients with CHD. Search methods We updated searches from the previous Cochrane review, by searching Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 6, 2014) from December 2009 to July 2014. We also searched MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCO) and Science Citation Index Expanded (December 2009 to July 2014). Selection criteria We included randomised controlled trials (RCTs) of exercise-based interventions with at least six months’ follow-up, compared with a no exercise control. The study population comprised men and women of all ages who have had a myocardial infarction (MI), coronary artery bypass graft (CABG) or percutaneous coronary intervention (PCI), or who have angina pectoris, or coronary artery disease. We included RCTs that reported at least one of the following outcomes: mortality, MI, revascularisations, hospitalisations, health-related quality of life (HRQL), or costs. Data collection and analysis Two review authors independently screened all identified references for inclusion based on the above inclusion and exclusion criteria. One author extracted data from the included trials and assessed their risk of bias; a second review author checked data. We stratified meta-analysis by the duration of follow up of trials, i.e. short-term: 6 to 12 months, medium-term: 13 to 36 months, and long-term: > 3 years. Main results This review included 63 trials which randomised 14,486 people with CHD. This latest update identified 16 new trials (3872 participants). The population included predominantly post-MI and post-revascularisation patients and the mean age of patients within the trials ranged from 47.5 to 71.0 years.Women accounted for fewer than 15% of the patients recruited. Overall trial reporting was poor, although there was evidence of an improvement in quality of reporting in more recent trials. As we found no significant difference in the impact of exercise-based CR on clinical outcomes across follow-up, we focused on reporting findings pooled across all trials at their longest follow-up (median 12 months). Exercise-based CR reduced cardiovascular mortality compared with no exercise control (27 trials; risk ratio (RR) 0.74, 95% CI 0.64 to 0.86). There was no reduction in total mortality with CR (47 trials, RR 0.96, 95% CI 0.88 to 1.04). The overall risk of hospital admissions was reduced with CR (15 trials; RR 0.82, 95% CI 0.70 to 0.96) but there was no significant impact on the risk of MI (36 trials; RR 0.90, 95% CI 0.79 to 1.04), CABG (29 trials; RR 0.96, 95% CI 0.80 to 1.16) or PCI (18 trials; RR 0.85, 95% CI 0.70 to 1.04). There was little evidence of statistical heterogeneity across trials for all event outcomes, and there was evidence of small study bias for MI and hospitalisation, but no other outcome. Predictors of clinical outcomes were examined across the longest follow-up of studies using univariate meta-regression. Results show that benefits in outcomes were independent of participants’ CHD case mix (proportion of patients with MI), type of CR (exercise only vs comprehensive rehabilitation) dose of exercise, length of follow-up, trial publication date, setting (centre vs home-based), study location (continent), sample size or risk of bias. Given the heterogeneity in outcome measures and reporting methods, meta-analysis was not undertaken for HRQL. In five out of 20 trials reporting HRQL using validated measures, there was evidence of significant improvement in most or all of the sub-scales with exercise-based CR compared to control at follow-up. Four trial-based economic evaluation studies indicated exercise-based CR to be a potentially cost-effective use of resources in terms of gain in quality-adjusted life years. The quality of the evidence for outcomes reported in the review was rated using the GRADE method. The quality of the evidence varied widely by outcome and ranged from low to moderate. Authors’ conclusions This updated Cochrane review supports the conclusions of the previous version of this review that, compared with no exercise control, exercise-based CR reduces the risk of cardiovascular mortality but not total mortality. We saw a significant reduction in the risk of hospitalisation with CR but not in the risk of MI or revascularisation. We identified further evidence supporting improved HRQL with exercise-based CR. More recent trials were more likely to be well reported and include older and female patients. However, the population studied in this review still consists predominantly of lower risk individuals following MI or revascularisation. Further well conducted RCTs are needed to assess the impact of exercise-based CR in higher risk CHD groups and also those presenting with stable angina. These trials should include validated HRQL outcome measures, explicitly report clinical event outcomes including mortality and hospital admissions, and assess costs and cost-effectiveness
Analysis and production of two exopolysaccharides from Lactococcus lactis subsp. cremoris LC330
Two polysaccharides produced concurrently by Lactococcus lactis subsp. cremoris strain LC330 have been identified. One had a high molecular mass (> 1 × 106 Da) and was neutral. The second was smaller ( 10000 Da), charged and had a high phosphorus content. Sugar composition also differed. In chemostat culture the neutral polysaccharide was influenced by temperature and by nitrogen limitation. This polysaccharide was branched with terminal galactose moieties and contained galactose, glucose and glucosamine. The phosphopolysaccharide was more complex with glucose, rhamnose, galactose and glucosamine in an approximate ratio of 6:5:4:
Computer Simulation of Global Profiles of Carbon Dioxide Using a Pulsed, 2-Micron, Coherent-Detection, Column-Content DIAL System
We present preliminary results of computer simulations of the error in measuring carbon dioxide mixing ratio profiles from earth orbit. The simulated sensor is a pulsed, 2-micron, coherent-detection lidar alternately operating on at least two wavelengths. The simulated geometry is a nadir viewing lidar measuring the column content signal. Atmospheric absorption is modeled using FASCODE3P software with the HITRAN 2004 absorption line data base. Lidar shot accumulation is employed up to the horizontal resolution limit. Horizontal resolutions of 50, 100, and 200 km are shown. Assuming a 400 km spacecraft orbit, the horizontal resolutions correspond to measurement times of about 7, 14, and 28 s. We simulate laser pulse-pair repetition frequencies from 1 Hz to 100 kHz. The range of shot accumulation is 7 to 2.8 million pulse-pairs. The resultant error is shown as a function of horizontal resolution, laser pulse-pair repetition frequency, and laser pulse energy. The effect of different on and off pulse energies is explored. The results are compared to simulation results of others and to demonstrated 2-micron operating points at NASA Langley
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