11,121 research outputs found

    POLITICAL COMPONENTS IN CURRENT AGRICULTURAL POLICY FORMATION

    Get PDF
    Agricultural and Food Policy,

    Analysis of Meteorological Data Obtained During Flight in a Supercooled Stratiform Cloud of High Liquid-Water Content

    Get PDF
    Flight icing-rate data obtained in a dense and. abnormally deep supercooled stratiform cloud system indicated the existence of liquid-water contents generally exceeding values in amount and extent previously reported over the midwestern sections of the United States. Additional information obtained during descent through a part of the cloud system indicated liquid-water contents that significantly exceeded theoretical values, especially near the middle of the cloud layer.. The growth of cloud droplets to sizes that resulted in sedimentation from the upper portions of the cloud is considered to be a possible cause of the high water contents near the center of the cloud layer. Flight measurements of the vertical temperature distribution in the cloud layer indicated a rate of change of temperature with altitude exceeding that of the moist adiabatic lapse rate. This excessive rate of change is considered to have contributed to the severity of the condition

    The crisis of public sector trade unionism: evidence from the Mid Staffordshire hospital crisis

    Get PDF
    This article contends that there is a growing, if uneven, crisis in public sector trade unionism masked by relatively high membership figures that obscure a weakening of trade unions in the workplace, leaving hollowed out organisation vulnerable to further legislative and employer-led onslaughts. The weakening is not inevitable but to overcome it requires a refocusing of organising efforts on the everyday concerns of members such as understaffing and the provision of better public services. Only with an engaged membership will national issues and wider campaigns have material force. Having outlined a general argument, the article takes as illustrative the nature and performance of trade unions, and particularly UNISON, during the Mid Staffordshire hospital crisis

    Utilization of Landsat Imagery to Assess the Impacts of Oil and Gas Extraction on the Tazovsky Peninsula, Siberia

    Get PDF
    Climatic warming of the Arctic is leading to landscape change through cascading biophysical feedbacks; development, such as oil and gas exploration and extraction, can accelerate or worsen these impacts. Due to restricted access to oil and natural gas fields, in situ environmental impact studies are only allowed in some regions. Satellite imagery analysis provides a mean for assessing impacts in areas with limited access. The Yamburg oil and gas field in western Siberia serves as a case study to assess the effects of infrastructure on an Arctic landscape. This project quantifies the land-cover disturbance that occurred during the development and expansion of the Yamburg field. Google’s recently developed, cloud-based image processing platform, Google Earth Engine, was used in conjunction with traditional Geographic Information System (GIS) analysis to detect, map, and quantify the impacts of infrastructure on the Tazovsky Peninsula between 1983 and 2016, utilizing imagery from the Landsat 4, 5, and 8 satellites. Landscape fragmentation metrics, the Normalized Difference Vegetation Index (NDVI), and change analysis quantified the impacts of extraction infrastructure on the surrounding landscape. As distance from the infrastructure and time since field establishment increased, the associated impacts decreased

    Urine metabolomic analysis to detect metabolites associated with the development of contrast induced nephropathy.

    Get PDF
    ObjectiveContrast induced nephropathy (CIN) is a result of injury to the proximal tubules. The incidence of CIN is around 11% for imaging done in the acute care setting. We aim to analyze the metabolic patterns in the urine, before and after dosing with intravenous contrast for computed tomography (CT) imaging of the chest, to determine if metabolomic changes exist in patients who develop CIN.MethodsA convenience sample of high risk patients undergoing a chest CT with intravenous contrast were eligible for enrollment. Urine samples were collected prior to imaging and 4 to 6 hours post imaging. Samples underwent gas chromatography/mass spectrometry profiling. Peak metabolite values were measured and data was log transformed. Significance analysis of microarrays and partial least squares was used to determine the most significant metabolites prior to CT imaging and within subject. Analysis of variance was used to rank metabolites associated with temporal change and CIN. CIN was defined as an increase in serum creatinine level of ≥ 0.5 mg/dL or ≥ 25% above baseline within 48 hours after contrast administration.ResultsWe sampled paired urine samples from 63 subjects. The incidence of CIN was 6/63 (9.5%). Patients without CIN had elevated urinary citric acid and taurine concentrations in the pre-CT urine. Xylulose increased in the post CT sample in patients who developed CIN.ConclusionDifferences in metabolomics patterns in patients who do and do not develop CIN exist. Metabolites may be potential early identifiers of CIN and identify patients at high-risk for developing this condition prior to imaging

    Investigation of Meteorological Conditions Associated with Aircraft Icing in Layer-Type Clouds for 1947-48 Winter

    Get PDF
    Rotating-cylinder measurements of the icing conditions encountered in flight during the winter of 1947-48 are presented. Liquid water content, drop size, and temperature data are shown to be consistent with previously measured conditions and with proposed maximum icing conditions in supercooled layer-type clouds. Cumulative frequency graphs of meteorological parameters indicate the frequency with which various icing conditions have been encountered in the Great Lakes area and surrounding states

    Adapting to Misspecification

    Full text link
    Empirical research typically involves a robustness-efficiency tradeoff. A researcher seeking to estimate a scalar parameter can invoke strong assumptions to motivate a restricted estimator that is precise but may be heavily biased, or they can relax some of these assumptions to motivate a more robust, but variable, unrestricted estimator. When a bound on the bias of the restricted estimator is available, it is optimal to shrink the unrestricted estimator towards the restricted estimator. For settings where a bound on the bias of the restricted estimator is unknown, we propose adaptive shrinkage estimators that minimize the percentage increase in worst case risk relative to an oracle that knows the bound. We show that adaptive estimators solve a weighted convex minimax problem and provide lookup tables facilitating their rapid computation. Revisiting five empirical studies where questions of model specification arise, we examine the advantages of adapting to -- rather than testing for -- misspecification.Comment: 69 pages, 12 figure
    • …
    corecore