6,246 research outputs found
Using experiments and expert judgment to model catchability of Pacific rockfishes in trawl surveys, with application to bocaccio (Sebastes paucispinis) off British Columbia
The time series of abundance indices for many groundfish
populations, as determined from trawl surveys, are often imprecise and short, causing stock assessment estimates
of abundance to be imprecise. To improve precision, prior probability distributions (priors) have been developed
for parameters in stock assessment models by using meta-analysis, expert judgment on catchability, and empirically based modeling. This article presents a synthetic approach for formulating priors for rockfish trawl survey catchability (qgross). A multivariate prior for qgross for different surveys is formulated by using 1) a correction factor for bias in estimating fish density between trawlable and untrawlable areas, 2) expert judgment on trawl net catchability, 3) observations from trawl survey experiments, and 4) data on the fraction of population
biomass in each of the areas surveyed. The method is illustrated by using bocaccio (Sebastes paucipinis) in British Columbia. Results indicate that expert judgment can be updated markedly by observing the catch-rate ratio from different trawl gears in the same areas. The marginal priors
for qgross are consistent with empirical estimates obtained by fitting a stock assessment model to the survey data under a noninformative prior for qgross. Despite high prior uncertainty (prior coefficients of variation ≥0.8) and high prior correlation between qgross, the prior for qgross still enhances the precision of key stock assessment
quantities
Effect of closing facilities on electroconvulsive therapy use in Glasgow
<p>Objectives: To assess the effect of closure of electroconvulsive therapy (ECT) centers on ECT use. Electroconvulsive therapy remains a recommended and effective treatment for mental disorders. Declining rates
of ECT use in the United Kingdom have been observed over the last 20 years with anecdotal observations that use has declined as the result of centralization of provision. In Glasgow, there have been site closures in the north with no such rationing taking place in the south.</p>
<p>Methods: A naturalistic retrospective survey of the number of ECT
courses commenced each year in Glasgow, with a comparison made between the north and the south of the city. Data were available from 1996 to 2008.</p>
<p>Results: Our analysis showed no change in the mean number of ECT courses commenced in southern AQ2 Glasgow (period 1, 42.25; period 2, 41.83; period 3, 31; F = 1.369; P = 0.298). There was a significant reduction in the mean number of ECT treatments commenced in northern Glasgow (period 1, 91.25; period 2, 51; period 3, 33.33; F = 10.06; P = 0.04).</p>
<p>Conclusions: In northern Glasgow, where there have been 2 site closures since 1996, ECT use has declined. This trend was not replicated in the south of the city. This would suggest that the closure of ECT centers does reduce the use of ECT. However, there may be a number of confounding variables that could not be factored into the analysis because of lack of available data.</p>
Parallel algorithms for interactive manipulation of digital terrain models
Interactive three-dimensional graphics applications, such as terrain data representation and manipulation, require extensive arithmetic processing. Massively parallel machines are attractive for this application since they offer high computational rates, and grid connected architectures provide a natural mapping for grid based terrain models. Presented here are algorithms for data movement on the massive parallel processor (MPP) in support of pan and zoom functions over large data grids. It is an extension of earlier work that demonstrated real-time performance of graphics functions on grids that were equal in size to the physical dimensions of the MPP. When the dimensions of a data grid exceed the processing array size, data is packed in the array memory. Windows of the total data grid are interactively selected for processing. Movement of packed data is needed to distribute items across the array for efficient parallel processing. Execution time for data movement was found to exceed that for arithmetic aspects of graphics functions. Performance figures are given for routines written in MPP Pascal
Interaction of herbicides and early-season insecticides on thrips populations and plant growth characteristics on herbicide-tolerant transgenic cotton
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Management of early pregnancy loss with mifepristone and misoprostol: clinical predictors of treatment success from a randomized trial.
BackgroundEarly pregnancy loss is a common event in the first trimester, occurring in 15%-20% of confirmed pregnancies. A common evidence-based medical regimen for early pregnancy loss uses misoprostol, a prostaglandin E1 analog, with a dosage of 800 μg, self-administered vaginally. The clinical utility of this regimen is limited by suboptimal effectiveness in patients with a closed cervical os, with 29% of patients experiencing early pregnancy loss requiring a second dose after 3 days and 16% of patients eventually requiring a uterine aspiration procedure.ObjectiveThis study aimed to evaluate clinical predictors associated with treatment success in patients receiving medical management with mifepristone-misoprostol or misoprostol alone for early pregnancy loss.Study designWe performed a planned secondary analysis of a randomized trial comparing mifepristone-misoprostol with misoprostol alone for management of early pregnancy loss. The published prediction model for treatment success of single-dose misoprostol administered vaginally included the following variables: active bleeding, type of early pregnancy loss (anembryonic pregnancy or embryonic and/or fetal demise), parity, gestational age, and treatment site; previous significant predictors were vaginal bleeding within the past 24 hours and parity of 0 or 1 vs >1. To determine if these characteristics predicted differential proportions of patients with treatment success or failure, we performed bivariate analyses; given the small proportion of treatment failures in the combined treatment arm, both arms were combined for analysis. Thereafter, we performed a logistic regression analysis to assess the effect of these predictors collectively in each of the 2 treatment groups separately as well as in the full cohort as a proxy for the combined treatment arm. Finally, by using receiver operating characteristic curves, we tested the ability of these predictors in association with misoprostol treatment success to discriminate between treatment success and treatment failure. To quantify the ability of the score to discriminate between treatment success and treatment failure in each treatment arm as well as in the entire cohort, we calculated the area under the curve. Using multivariable logistic regression, we then assessed our study population for other predictors of treatment success in both treatment groups, with and without mifepristone pretreatment.ResultsOverall, 297 evaluable participants were included in the primary study, with 148 in the mifepristone-misoprostol combined treatment group and 149 in the misoprostol-alone treatment group. Among patients who had vaginal bleeding at the time of treatment, 15 of 17 (88%) in the mifepristone-misoprostol combined treatment group and 12 of 17 (71%) in the misoprostol-alone treatment group experienced expulsion of pregnancy tissue. Among patients with a parity of 0 or 1, 94 of 108 (87%) in the mifepristone-misoprostol treatment group and 66 of 95 (69%) in the misoprostol-alone treatment group experienced expulsion of pregnancy tissue. These clinical characteristics did not predict treatment success in the combined cohort alone (area under the curve=0.56; 95% confidence interval, 0.48-0.64). No other baseline clinical factors predicted treatment success in the misoprostol-alone treatment arm or mifepristone pretreatment arm. In the full cohort, the significant predictors of treatment success were pretreatment with mifepristone (adjusted odds ratio=2.51; 95% confidence interval, 1.43-4.43) and smoking (adjusted odds ratio=2.15; 95% confidence interval, 1.03-4.49).ConclusionNo baseline clinical factors predicted treatment success in women receiving medical management with misoprostol for early pregnancy loss. Adding mifepristone to the medical management regimen of early pregnancy loss improved treatment success; thus, mifepristone treatment should be considered for management of early pregnancy loss regardless of baseline clinical factors
The Print Book Purging Predicament: Qualitative Techniques for a Balanced Collection
At previous Charleston Conference meetings, there was much discussion about how to massively and efficiently weed collections across disciplines using quantitative criteria. The presenters recently published an article in Collection Management entitled “Weeding with Wisdom: Tuning Deselection of Print Monographs in Book-Reliant Disciplines” in which they argue for the importance of retaining some print materials in areas such as history and literature where scholars are dependent on older, lesser-used materials for their research and teaching. Presenters offered suggestions and invited discussion on ways to improve the deselection process through the use of qualitative techniques for weeding book-reliant disciplines in an attempt to maximize the quality of a monograph collection
Lifelong Learning or Lifelong Listening? Transforming the Learning Experiences of Older Adults in Higher Education in Scotland through Dialogue
This paper proposes that theorising about widening participation pedagogic practice in relation to older adults can be significantly developed by integrating insights from critical educational gerontology and academic literacies perspectives. We examine the possibilities of this theoretical development by drawing on two exploratory research projects with 20 older students in a Scottish university, proposing dialogue can act as a catalyst for making the opaque, transparent and learning experiences, transformative
Lifelong learning or lifelong listening? Transforming the learning experiences of older adults in Higher Education in Scotland through dialogue: Theory development paper
This paper proposes that theorising about widening participation pedagogic practice in relation to older adults can be significantly developed by integrating insights from critical educational gerontology and academic literacies perspectives. We examine the possibilities of this theoretical development by drawing on two exploratory research projects with 20 older students in a Scottish university, proposing dialogue can act as a catalyst for making the opaque, transparent and learning experiences, transformative
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