805 research outputs found

    Cost Finding for Railroads

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    Modernism, Responsibility, and the Novel

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    Through formal innovation and experimentation—and through a renewed commitment to human subjectivity—many modernist writers consciously disrupted traditional modes of narration. In doing so, their writing simultaneously engaged ethical questions about responsibly representing the alterity of the other. With particular attention to narrative fragmentation, I claim that reading modernism in terms of responsibility yields an uncommon yet critical understanding of its practitioners as deeply invested in ethical problems related to representation. I argue that in the context of British modernism, particularly in the decade following the Great War, many writers developed narrative strategies that anticipated, welcomed, and responded to the irruption of “the new” into a world of repose, order, and complacency. This dissertation therefore explores the concept of ethical responsibility as it relates to representation and self-other relationships in the three British modernist novels: Virginia Woolf’s Jacob’s Room (1922), D. H. Lawrence’s Aaron’s Rod (1922), and E. M. Forster’s A Passage to India (1924). I draw on the work of Emmanuel Levinas and Jacques Derrida to show that while modernists mindfully broke with representational practices of the past, they also felt themselves beset by the terrible burden of “making it new.” I demonstrate that this burden, or anxiety, is experienced by modernist narrators, characters, and readers

    International photovoltaic program. Volume 2: Appendices

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    The results of analyses conducted in preparation of an international photovoltaic marketing plan are summarized. Included are compilations of relevant statutes and existing Federal programs; strategies designed to expand the use of photovoltaics abroad; information on the domestic photovoltaic plan and its impact on the proposed international plan; perspectives on foreign competition; industry views on the international photovoltaic market and ideas about the how US government actions could affect this market;international financing issues; and information on issues affecting foreign policy and developing countries

    Atomic oxygen degradation of Intelsat 4-type solar array interconnects: Laboratory investigations

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    A Hughes 506 type communication satellite belonging to the Intelsat organization was marooned in low Earth orbit on March 14, 1990, following failure of the Titan third stage to separate properly. The satellite, Intelsat VI, was designed for service in geosynchronous orbit and contains several material configurations which are susceptible to attack by atomic oxygen. Analysis showed the silver foil interconnects in the satellite photovoltaic array to be the key materials issue because the silver is exposed directly to the atomic oxygen ram flux. The results are reported of atomic oxygen degradation testing of Intelsat VI type silver foil interconnects both as virgin material and in a configured solar cell element. Test results indicate that more than 80 pct. of the original thickness of silver in the Intelsat VI solar array interconnects should remain after completion of the proposed Space Shuttle rescue and/or reboost mission

    Modeling Mutualism and Competition in Interactive Population Dynamics: How Ants and Aphids Affect Lycaenid Butterfly Ecology

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    Modeling population dynamics that include mutualistic interactions is an important and complex problem in theoretical biology and quantitative ecology. Mutualistic interactions, which are generally considered relationships in which two or more species benefit from each other’s presence, play a significant role in determining population dyanmics, and are essential to fully understanding the dynamics of interacting species. However, mutualistic interactions are a historically understudied topic in ecology; accurately describing populations in multi-species interactions is inherently challenging (Hastings & Powell, 1991), and models describing these populations increase greatly in complexity as the intricacy and interdependence of the relationship increases. As such, there have been relatively few attempts within the field to fully account for the particulars of these relationships. Through numerical simulation of lycaenid butterfly and aphid populations together with deterministic and stochastic mathematical models, this research aims to more thoroughly explore the facets of mutualistic and competitive interactions in population dynamics. By refining a previous model for lycaenid butterfly populations (Forister, Gompert, Nice, & Fordyce, 2010) and by adapting the models to include the dynamics of two interactive species, ants and aphids, we hope to generate a model which simultaneously predicts the fluctuation in the focal species while providing insight to the rich and complex interplay of mutualistic and competitive interactions in theoretical ecology. By using this model to examine the population dynamics of these species, we hope to generate a method which will be useful in explaining endangered lycaenid butterfly populations as well as understanding the role of mutualism in the context of quantitative and theoretical ecology

    Strong trait correlation and phylogenetic signal in North American ground beetle (Carabidae) morphology

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    Functional traits mediate species’ responses to, and roles within, their environment and are constrained by evolutionary history. While we have a strong understanding of trait evolution for macrotaxa such as birds and mammals, our understanding of invertebrates is comparatively limited. Here, we address this gap in North American beetles with a sample of ground beetles (Carabidae), leveraging a large-scale collection and digitization effort by the National Ecological Observatory Network (NEON). For 154 ground beetle species, we measured seven morphological traits, which we placed into a recently developed effect–response framework that characterizes traits by how they predict species’ effects on their ecosystems or responses to environmental stressors. We then used cytochrome oxidase 1 sequences from the same specimens to generate a phylogeny and tested the evolutionary tempo and mode of the traits. We found strong phylogenetic signal in, and correlations among, ground beetle morphological traits. These results indicate that, for these species, beetle body shape trait evolution is constrained, and phylogenetic inertia is a stronger driver of beetle traits than (recent) environmental responses. Strong correlations among effect and response traits suggest that future environmental drivers are likely to affect both ecological composition and functioning in these beetles

    Disseminated Mycobacterium genavense Infection in Two Patients with AIDS

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    Mycobacterium genavense is a recently defined fastidious organism that has been identified as a cause of disseminated infection in patients with AIDS. We report the cases of two patients who had advanced AIDS and a clinical syndrome of fever, anorexia, abdominal pain, diarrhea, and weight loss. In addition, splenomegaly and lymphadenopathy were prominent in both cases, and in one patient's case radiographic findings were suggestive of splenic abscesses. Mycobacteria isolated from specimens of blood and bone marrow grew in liquid media but not on solid media. The results of DNA probe tests for Mycobacterium tuberculosis and Mycobacterium avium complex were false-positive for both patients. After treatment of the broth cultures to lyse red blood cells, the results of DNA probe tests were negative for these pathogens. Amplification and sequencing of 16S rRNA with use of the polymerase chain reaction indicated that the mycobacterial isolates from both patients had sequences identical to those previously reported for M. genavense. One patient survived 5 months after diagnosis, the other 2 months after diagnosis; only one patient responded (transiently) to antimycobacterial chemotherap

    Estimating the Effects of Astronaut Career Ionizing Radiation Dose Limits on Manned Interplanetary Flight Programs

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    Space radiation effects mitigation has been identified as one of the highest priority technology development areas for human space flight in the NASA Strategic Space Technology Investment Plan (Dec. 2012). In this paper we review the special features of space radiation that lead to severe constraints on long-term (more than 180 days) human flight operations outside Earth's magnetosphere. We then quantify the impacts of human space radiation dose limits on spacecraft engineering design and development, flight program architecture, as well as flight program schedule and cost. A new Deep Space Habitat (DSH) concept, the hybrid inflatable habitat, is presented and shown to enable a flexible, affordable approach to long term manned interplanetary flight today

    Aerosol Best Estimate Value-Added Product

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    The objective of the Aerosol Best Estimate (AEROSOLBE) value-added product (VAP) is to provide vertical profiles of aerosol extinction, single scatter albedo, asymmetry parameter, and Angstroem exponents for the atmospheric column above the Central Facility at the ARM Southern Great Plains (SGP) site. We expect that AEROSOLBE will provide nearly continuous estimates of aerosol optical properties under a range of conditions (clear, broken clouds, overcast clouds, etc.). The primary requirement of this VAP was to provide an aerosol data set as continuous as possible in both time and height for the Broadband Heating Rate Profile (BBHRP) VAP in order to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Even though BBHRP has been completed, AEROSOLBE results are very valuable for environmental, atmospheric, and climate research

    Deep Mapping of Small Solar System Bodies with Galactic Cosmic Ray Secondary Particle Showers

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    Galactic cosmic rays rain steadily from all directions onto asteroids and comets. The interaction of these high-energy ions produces a cascade of secondary particles, including muons, which can penetrate the solid interiors of small solar system bodies. Muons, which are produced in abundance in Earth's atmosphere, have been used to image large structures on Earth, including the Great Pyramids and the interior of volcanoes. In this study, we demonstrate that the transmitted flux of muons is sensitive to the interior density structure of asteroids and comets, less than a few hundred meters in diameter. Muonography has the potential to fill a critical gap in our knowledge of the deep interiors of small bodies, providing information needed for planetary defense, in situ resource utilization, and planetary science. We use Monte Carlo codes (MCNPX and FLUKA), which accurately model galactic cosmic ray showers, to explore systematic variations in the production of muons in solid surfaces. Results of these calculations confirm the scaling of muon production in Earth's atmosphere to solid regolith materials, as predicted by a simple, semi-empirical model. Muons are primarily produced in the top meter of the regoliths of asteroids and comets. Their rate of production is over three orders of magnitude lower than in Earth's atmosphere and depends strongly on regolith density. In practice, the use of muonography to characterize the interiors of small solar system bodies must overcome their low rate of production and their dependence on regolith density, which can vary over the surface of asteroids and comets. We show that interior contrast can be resolved using a muon telescope (hodoscope) with about 1 sq m aperture with integration times ranging from hours to weeks. Design concepts for a practical hodoscope that could be deployed in situ or on an orbiting spacecraft, are described. Regolith density within the top meter of an asteroid can be determined from radar observations. A concept for a pilot mission that combines remote radar measurements with in situ muonography of a near-Earth asteroid is presented. Perceived challenges and next steps for the development of the concept are described
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