2,977 research outputs found

    What can management theories offer evidence-based practice? A comparative analysis of measurement tools for organisational context

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    Background: Given the current emphasis on networks as vehicles for innovation and change in health service delivery, the ability to conceptualise and measure organisational enablers for the social construction of knowledge merits attention. This study aimed to develop a composite tool to measure the organisational context for evidence-based practice (EBP) in healthcare. Methods: A structured search of the major healthcare and management databases for measurement tools from four domains: research utilisation (RU), research activity (RA), knowledge management (KM), and organisational learning (OL). Included studies were reports of the development or use of measurement tools that included organisational factors. Tools were appraised for face and content validity, plus development and testing methods. Measurement tool items were extracted, merged across the four domains, and categorised within a constructed framework describing the absorptive and receptive capacities of organisations. Results: Thirty measurement tools were identified and appraised. Eighteen tools from the four domains were selected for item extraction and analysis. The constructed framework consists of seven categories relating to three core organisational attributes of vision, leadership, and a learning culture, and four stages of knowledge need, acquisition of new knowledge, knowledge sharing, and knowledge use. Measurement tools from RA or RU domains had more items relating to the categories of leadership, and acquisition of new knowledge; while tools from KM or learning organisation domains had more items relating to vision, learning culture, knowledge need, and knowledge sharing. There was equal emphasis on knowledge use in the different domains. Conclusion: If the translation of evidence into knowledge is viewed as socially mediated, tools to measure the organisational context of EBP in healthcare could be enhanced by consideration of related concepts from the organisational and management sciences. Comparison of measurement tools across domains suggests that there is scope within EBP for supplementing the current emphasis on human and technical resources to support information uptake and use by individuals. Consideration of measurement tools from the fields of KM and OL shows more content related to social mechanisms to facilitate knowledge recognition, translation, and transfer between individuals and groups

    General Relativistic Simulations of Magnetized Plasmas around Merging Supermassive Black Holes

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    Coalescing supermassive black hole binaries are produced by the mergers of galaxies and are the most powerful sources of gravitational waves accessible to space-based gravitational observatories. Some such mergers may occur in the presence of matter and magnetic fields and hence generate an electromagnetic counterpart. In this Letter, we present the first general relativistic simulations of magnetized plasma around merging supermassive black holes using the general relativistic magnetohydrodynamic code Whisky. By considering different magnetic field strengths, going from non-magnetically dominated to magnetically dominated regimes, we explore how magnetic fields affect the dynamics of the plasma and the possible emission of electromagnetic signals. In particular we observe a total amplification of the magnetic field of ~2 orders of magnitude which is driven by the accretion onto the binary and that leads to much stronger electromagnetic signals, more than a factor of 10^4 larger than comparable calculations done in the force-free regime where such amplifications are not possible.Comment: 7 pages, 5 figures. Minor changes to match version accepted for publication on The Astrophysical Journal Letter

    Caisson Load Test and Instrumentation Program – Sohio Corporate Headquarters

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    The Sohio Corporate Headquarters building foundations in Cleveland, Ohio are relatively unique, involving as they do some of the deepest caissons on record, combined with a socket friction design. This paper reports the performance of a full-scale load test and the results of instrumentation programs performed to evaluate the design and performance of 240-ft (73 m) deep rock socket caissons at the Sohio Corporate Headquarters building project. The load test was carried out to 2.5 times the theoretical design capacity and the results are reviewed in terms of both total capacity and the individual design parameters, such as socket friction. Details of the instrumentation program used to evaluate concrete strain and corresponding load transference as a function of applied load, caisson depth, and time are also presented. In addition to the load test, the installation details and results of a production caisson instrumentation program to permit long-term monitoring of concrete stress and strain levels are reviewed

    Design of Setups for Plasma Propulsion Plume Experiments

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    The project involves design, analysis and fabrication of setups to be used in experiments with plasma plumes from electric micropropulsion devices. The setup for a 1.25m diameter 1.845m long large vacuum chamber includes a fixed plasma source stand and a translating plasma diagnostics stand. Design and structural analysis are performed using Solidworks and COMSOL Multiphysics. The setup for a 0.57m diameter,0.55m long small vacuum chamber includes a plasma diagnostics stand placed on a manual translation table along the plume axis. The realized design involves motorized transverse and rotary stages to align a Langmuir probe with the direction of the ion plume flow. Estimates of plume properties needed for probe sizing are obtained with simulations using a particle in cell plasma code

    Oil Pollution in Ecuador: A Devised Remediation Approach

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    Research is required to remediate the oil contamination left by Texaco in Ecuador and its effects. These effects and potential methods of their remediation are analyzed with respect to water, soil, and the affected indigenous peoples. We propose a five-part approach to the contamination, the Five Components of Remediation, which is divided into the Primary Component, Site Assessment, and the Four Ancillary Components: Water Treatment, Source Removal, Soil Treatment, and Minimization of Psychological and Sociological Impacts

    An authoritative global database for active submarine hydrothermal vent fields

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    Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 14 (2013): 4892–4905, doi:10.1002/2013GC004998.The InterRidge Vents Database is available online as the authoritative reference for locations of active submarine hydrothermal vent fields. Here we describe the revision of the database to an open source content management system and conduct a meta-analysis of the global distribution of known active vent fields. The number of known active vent fields has almost doubled in the past decade (521 as of year 2009), with about half visually confirmed and others inferred active from physical and chemical clues. Although previously known mainly from mid-ocean ridges (MORs), active vent fields at MORs now comprise only half of the total known, with about a quarter each now known at volcanic arcs and back-arc spreading centers. Discoveries in arc and back-arc settings resulted in an increase in known vent fields within exclusive economic zones, consequently reducing the proportion known in high seas to one third. The increase in known vent fields reflects a number of factors, including increased national and commercial interests in seafloor hydrothermal deposits as mineral resources. The purpose of the database now extends beyond academic research and education and into marine policy and management, with at least 18% of known vent fields in areas granted or pending applications for mineral prospecting and 8% in marine protected areas.For support to prepare this manuscript, we thank the National Science Foundation (OCE08-38923, GeoEd12-02977), the NOAA Vents (now Earth-Ocean Interactions) Program and the Joint Institute for the Study of the Atmosphere and Ocean (JISAO) under NOAA Cooperative Agreement NA10OAR4320148, and WHOI.2014-05-1

    Neutral delay differential equations in the modelling of cell growth

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    In this contribution, we indicate (and illustrate by example) roles that may be played by neutral delay differential equations in modelling of certain cell growth phenomena that display a time lag in reacting to events. We explore, in this connection, questions involving the sensitivity analysis of models and related mathematical theory; we provide some associated numerical results

    Oral Administration of Levo-Tetrahydropalmatine Attenuates Reinstatement of Extinguished Cocaine Seeking by Cocaine, Stress or Drug-Associated Cues in Rats

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    Cocaine addiction is characterized by a persistently heightened susceptibility to drug relapse. For this reason, the identification of medications that prevent drug relapse is a critical goal of drug abuse research. Drug re-exposure, the onset of stressful life events, and exposure to cues previously associated with drug use have been identified as determinants of relapse in humans and have been found to reinstate extinguished cocaine seeking in rats. This study examined the effects of acute oral (gavage) administration of levo-tetrahydropalmatine (l-THP), a tetrahydroprotoberberine isoquinoline with a pharmacological profile that includes antagonism of D1, D2 and D3 dopamine receptors, on the reinstatement of extinguished cocaine seeking by a cocaine challenge (10 mg/kg, ip), a stressor (uncontrollable electric footshock [EFS]) or response-contingent exposure to a stimulus (tone and light complex) previously associated with drug delivery in male Sprague–Dawley rats. Extinguished drug seeking was reinstated by ip cocaine, EFS, or response-contingent presentation of drug-associated cues in vehicle-pretreated rats following extinction of iv cocaine self-adminisration. Oral administration of either 3.0 or 10.0 mg/kg l-THP 1 h prior to reinstatement testing significantly attenuated reinstatement by each of the stimuli. Food-reinforced responding and baseline post-extinction responding were significantly attenuated at the 10.0, but not the 3.0 mg/kg, l-THP dose, indicating that the effects of 3 mg/kg l-THP on reinstatement were likely independent of non-specific motor impairment. These findings further suggest that l-THP may have utility for the treatment of cocaine addiction
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