39 research outputs found

    Preorganized tridentate analogues of mixed hydroxyoxime/carboxylate nickel extractants

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    Simple tridentate ligands can operate as Ni-extractants in the pH-dependent process: 2LHorg + NiSO4 ⇌ [(L)2Ni]org + H2SO4.</p

    Very Low-mass Stellar and Substellar Companions to Solar-like Stars from MARVELS II: A Short-period Companion Orbiting an F Star with Evidence of a Stellar Tertiary And Significant Mutual Inclination

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    We report the discovery via radial velocity of a short-period (P = 2.430420 \pm 0.000006 days) companion to the F-type main sequence star TYC 2930-00872-1. A long-term trend in the radial velocities indicates the presence of a tertiary stellar companion with P>2000P > 2000 days. High-resolution spectroscopy of the host star yields T_eff = 6427 +/- 33 K, log(g) = 4.52 +/- 0.14, and [Fe/H]=-0.04 +/- 0.05. These parameters, combined with the broad-band spectral energy distribution and parallax, allow us to infer a mass and radius of the host star of M_1=1.21 +/- 0.08 M_\odot and R_1=1.09_{-0.13}^{+0.15} R_\odot. We are able to exclude transits of the inner companion with high confidence. The host star's spectrum exhibits clear Ca H and K core emission indicating stellar activity, but a lack of photometric variability and small v*sin(I) suggest the primary's spin axis is oriented in a pole-on configuration. The rotational period of the primary from an activity-rotation relation matches the orbital period of the inner companion to within 1.5 \sigma, suggesting they are tidally locked. If the inner companion's orbital angular momentum vector is aligned with the stellar spin axis, as expected through tidal evolution, then it has a stellar mass of M_2 ~ 0.3-0.4 M_\odot. Direct imaging limits the existence of stellar companions to projected separations < 30 AU. No set of spectral lines and no significant flux contribution to the spectral energy distribution from either companion are detected, which places individual upper mass limits of M < 1.0 M_\odot, provided they are not stellar remnants. If the tertiary is not a stellar remnant, then it likely has a mass of ~0.5-0.6 M_\odot, and its orbit is likely significantly inclined from that of the secondary, suggesting that the Kozai-Lidov mechanism may have driven the dynamical evolution of this system.Comment: 37 pages, 7 tables, 21 figures, Accepted in A

    The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

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    Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

    The Internal Representations Questionnaire: Measuring modes of thinking

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    Does the format in which we experience our moment-to-moment thoughts vary from person to person? Many people strongly endorse that their thinking takes place in an inner voice and that using language outside of interpersonal communication is a regular experience for them. Other people disagree. We present a novel measure, the Internal Representation Questionnaire (IRQ) designed to assess people’s subjective mode of internal representations, and to quantify individual differences in “modes of thinking” along multiple factors in a single questionnaire. Exploratory factor analysis identified four factors: propensity to verbalize, visual imagery, orthographic imagery, and representational manipulation. All four factors were positively correlated, but accounted for unique predictions. We describe the properties of the IRQ and report a test of its ability to predict patterns of interference in a speeded word-picture verification task. Taken together, the results suggest that self-reported differences in how people “think” relate to differences in processing familiar images and text

    LibQUAL+ 2014 Survey Results -- University of Oregon Libraries

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    111 pagesThis notebook contains information from the 2010 administration of the LibQUAL+® protocol. The material on the following pages is drawn from the analysis of responses from the University of Oregon Libraries collected in 2014

    Surveys of Reporting Practices of Institutional Repositories

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    <p>This dataset contains the summary results of two surveys, which gathered data about the reporting practices for institutional repositories (IR). The surveys were completed by library directors and IR managers, and questions were asked about strategic importance, content scope, and the methods and mechanisms libraries utilize to evaluate and report on IR use and impact. </p

    LibQUAL+® 2010 Survey Results - Georgia Institute of Technology

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    © 2010 Association of Research Librarie

    LibQUAL+® 2013 Survey Results – Georgia Tech

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    © 2013 Association of Research Librarie
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