3,830 research outputs found

    The Space Object Ontology

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    Achieving space domain awareness requires the identification, characterization, and tracking of space objects. Storing and leveraging associated space object data for purposes such as hostile threat assessment, object identification, and collision prediction and avoidance present further challenges. Space objects are characterized according to a variety of parameters including their identifiers, design specifications, components, subsystems, capabilities, vulnerabilities, origins, missions, orbital elements, patterns of life, processes, operational statuses, and associated persons, organizations, or nations. The Space Object Ontology provides a consensus-based realist framework for formulating such characterizations in a computable fashion. Space object data are aligned with classes and relations in the Space Object Ontology and stored in a dynamically updated Resource Description Framework triple store, which can be queried to support space domain awareness and the needs of spacecraft operators. This paper presents the core of the Space Object Ontology, discusses its advantages over other approaches to space object classification, and demonstrates its ability to combine diverse sets of data from multiple sources within an expandable framework. Finally, we show how the ontology provides benefits for enhancing and maintaining longterm space domain awareness

    Australian real estate management and development companies and women directors

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    Purpose – There is a large literature advocating the importance of a greater proportion of women directors on boards of publicly listed firms. The purpose of this paper is to examine the numbers and proportions of women directors, including women executive directors, on listed Australian Real Estate Management and Development (REMD) companies to identify how prevalent women directors are on such boards. Design/methodology/approach – The study examines the numbers and proportions of women directors for 35 REMDs in 2011 and compares this to the broad board composition data on 1,715 Australian Stock Exchange listed entities. Statistically significant findings are evident due to the identified low proportions. Findings – The study finds that of all the Financials Sub Industry sector groups, REMDs have the lowest proportion of female directors on theirs boards – eight women on each of 35 company boards compared to 159 men on these 35 boards at 2011. Of the eight, there were only two women executive directors on boards compared to 50 men. Statistically, it appears that having women directors on REMD boards is not considered important. Even at December 2014, there are only ten women on seven company boards and only one remaining executive director of an REMD company. Practical implications – Given that female board representation is positively related to accounting returns and that there is a growing voice for legislation to impose mandatory proportions of women directors on boards around the world, it may be in the interests of REMD boards to consider appointing more women more quickly. Originality/value – The study is the first to examine the numbers and proportions of women directors amongst REMD companies to identify the paucity of such women directors

    La question de la sécurité pour une communauté politique sans souverain

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    André Brigot, professeur certifiéJohn-Christopher Barry, doctorant à l’EHESS La question de la sécurité pour une communauté politique sans souverain Le séminaire avait porté en 2010-2011 sur l’intégration de la notion de défense dans celle de sécurité et sur les définitions contemporaines de cette dernière. En 2011-2012, on a repris l’évolution de cette notion et surtout de cette fonction à travers quelques textes de philosophie politique, de l’Antiquité grecque, de la période médiévale, et s..

    La question de la sécurité pour une communauté politique sans souverain

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    André Brigot, professeur certifiéJohn-Christopher Barry, doctorant à l’EHESS La question de la sécurité pour une communauté politique sans souverain Le séminaire avait porté en 2010-2011 sur l’intégration de la notion de défense dans celle de sécurité et sur les définitions contemporaines de cette dernière. En 2011-2012, on a repris l’évolution de cette notion et surtout de cette fonction à travers quelques textes de philosophie politique, de l’Antiquité grecque, de la période médiévale, et s..

    Rolofylline, an adenosine A1−receptor antagonist, in acute heart failure

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    Background: Worsening renal function, which is associated with adverse outcomes, often develops in patients with acute heart failure. Experimental and clinical studies suggest that counterregulatory responses mediated by adenosine may be involved. We tested the hypothesis that the use of rolofylline, an adenosine A1−receptor antagonist, would improve dyspnea, reduce the risk of worsening renal function, and lead to a more favorable clinical course in patients with acute heart failure. Methods: We conducted a multicenter, double-blind, placebo-controlled trial involving patients hospitalized for acute heart failure with impaired renal function. Within 24 hours after presentation, 2033 patients were randomly assigned, in a 2:1 ratio, to receive daily intravenous rolofylline (30 mg) or placebo for up to 3 days. The primary end point was treatment success, treatment failure, or no change in the patient’s clinical condition; this end point was defined according to survival, heart-failure status, and changes in renal function. Secondary end points were the post-treatment development of persistent renal impairment and the 60-day rate of death or readmission for cardiovascular or renal causes. Results: Rolofylline, as compared with placebo, did not provide a benefit with respect to the primary end point (odds ratio, 0.92; 95% confidence interval, 0.78 to 1.09; P=0.35). Persistent renal impairment developed in 15.0% of patients in the rolofylline group and in 13.7% of patients in the placebo group (P=0.44). By 60 days, death or readmission for cardiovascular or renal causes had occurred in similar proportions of patients assigned to rolofylline and placebo (30.7% and 31.9%, respectively; P=0.86). Adverse-event rates were similar overall; however, only patients in the rolofylline group had seizures, a known potential adverse effect of A1-receptor antagonists. Conclusions: Rolofylline did not have a favorable effect with respect to the primary clinical composite end point, nor did it improve renal function or 60-day outcomes. It does not show promise in the treatment of acute heart failure with renal dysfunction. (Funded by NovaCardia, a subsidiary of Merck; ClinicalTrials.gov numbers, NCT00328692 and NCT00354458.

    A macroinvertebrate assessment of Ozark streams located in lead–zinc mining areas of the Viburnum Trend in southeastern Missouri, USA

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    The Viburnum Trend lead–zinc mining subdistrict is located in the southeast Missouri portion of the Ozark Plateau. In 2003 and 2004, we assessed the ecological effects of mining in several watersheds in the region. We included macroinvertebrate surveys, habitat assessments, and analysis of metals in sediment, pore water, and aquatic biota. Macroinvertebrates were sampled at 21 sites to determine aquatic life impairment status (full, partial, or nonsupport) and relative biotic condition scores. Macroinvertebrate biotic condition scores were significantly correlated with cadmium, nickel, lead, zinc, and specific conductance in 2003 (r = −0.61 to −0.68) and with cadmium, lead, and pore water toxic units in 2004 (r = −0.55 to −0.57). Reference sites were fully supporting of aquatic life and had the lowest metals concentrations and among the highest biotic condition scores in both years. Sites directly downstream from mining and related activities were partially supporting, with biotic condition scores 10% to 58% lower than reference sites. Sites located greater distances downstream from mining activities had intermediate scores and concentrations of metals. Results indicate that elevated concentrations of metals originating from mining activities were the underlying cause of aquatic life impairment in several of the streams studied. There was a general concurrence among the adversely affected sites in how the various indicators responded to the mining activities during the overall study

    Analysis of DGGE profiles to explore the relationship between prokaryotic community composition and biogeochemical processes in deep subseafloor sediments from the Peru Margin

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    The aim of this work was to relate depth profiles of prokaryotic community composition with geochemical processes in the deep subseafloor biosphere at two shallow-water sites on the Peru Margin in the Pacific Ocean (ODP Leg 201, sites 1228 and 1229). Principal component analysis of denaturing gradient gel electrophoresis banding patterns of deep-sediment Bacteria, Archaea, Euryarchaeota and the novel candidate division JS1, followed by multiple regression, showed strong relationships with prokaryotic activity and geochemistry (R2=55–100%). Further correlation analysis, at one site, between the principal components from the community composition profiles for Bacteria and 12 other variables quantitatively confirmed their relationship with activity and geochemistry, which had previously only been implied. Comparison with previously published cell counts enumerated by fluorescent in situ hybridization with rRNA-targeted probes confirmed that these denaturing gradient gel electrophoresis profiles described an active prokaryotic communit

    National Center for Biomedical Ontology: Advancing biomedicine through structured organization of scientific knowledge

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    The National Center for Biomedical Ontology is a consortium that comprises leading informaticians, biologists, clinicians, and ontologists, funded by the National Institutes of Health (NIH) Roadmap, to develop innovative technology and methods that allow scientists to record, manage, and disseminate biomedical information and knowledge in machine-processable form. The goals of the Center are (1) to help unify the divergent and isolated efforts in ontology development by promoting high quality open-source, standards-based tools to create, manage, and use ontologies, (2) to create new software tools so that scientists can use ontologies to annotate and analyze biomedical data, (3) to provide a national resource for the ongoing evaluation, integration, and evolution of biomedical ontologies and associated tools and theories in the context of driving biomedical projects (DBPs), and (4) to disseminate the tools and resources of the Center and to identify, evaluate, and communicate best practices of ontology development to the biomedical community. Through the research activities within the Center, collaborations with the DBPs, and interactions with the biomedical community, our goal is to help scientists to work more effectively in the e-science paradigm, enhancing experiment design, experiment execution, data analysis, information synthesis, hypothesis generation and testing, and understand human disease

    Stable isotopes reveal independent carbon pools across an Arctic hydro‐climatic gradient: implications for the fate of carbon in warmer and drier conditions

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    Arctic lakes are poised for substantial changes to their carbon (C) cycles in the near future. Autochthonous processes in lakes which consume inorganic C and create biomass that can be sequestered in sediments are accompanied by allochthonous inputs of organic matter from the surrounding watershed. Both C sources can be mineralized and degassed as CO2, but also become recalcitrant and accumulate in pelagic waters. Using stable carbon isotope (δ13C) values and elemental ratios as geochemical proxies, we investigated diverse organic matter sources to lakes located across a hydro‐climatic gradient in Southwest Greenland. Particulate organic matter (POM) and sediments were clearly of autochthonous algal origin, while dissolved organic matter (DOM) was a mix between autochthonous macrophytes and allochthonous watershed sources. Our results imply that a warmer and drier Arctic will lead to decoupled C pools: a water column dominated by increasingly autochthonous, macrophytic DOM, and sediments dominated by autochthonous algal POM
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