9,817 research outputs found

    The impact of degree field on the earnings of male and female college graduates

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    Since the gender demographics across majors have dramatically changed over the last few decades, a re-examination of the relationship between gender, undergraduate major selection, and compensation levels once in the workforce is important. This article will focus on how the salaries of college graduates have changed over the last decade. The analyses will explore the extent to which undergraduate major selection contributes to any male-female salary gap. A comparison of regression models for 1993 and 2001 describes the extent to which the selection of major remains a significant factor among those individuals who have entered the workforce

    Indicators of School Crime and Safety: 2012

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    Our nation's schools should be safe havens for teaching and learning, free of crime and violence. Any instance of crime or violence at school not only affects the individuals involved, but also may disrupt the educational process and affect bystanders, the school itself, and the surrounding community.Establishing reliable indicators of the current state of school crime and safety across the nation and regularly updating and monitoring these indicators is important in ensuring the safety of our nation's students. This is the aim of Indicators of School Crime and Safety. This report is the fifteenth in a series of annual publications produced jointly by the National Center for Education Statistics (NCES), Institute of Education Sciences (IES), in the U.S. Department of Education, and the Bureau of Justice Statistics (BJS) in the U.S. Department of Justice. This report presents the most recent data available on school crime and student safety. The indicators in this report are based on information drawn from a variety of data sources, including national surveys of students, teachers, and principals. Sources include results from the School-Associated Violent Deaths Study, sponsored by the U.S. Department of Education, the Department of Justice, and the Centers for Disease Control and Prevention; the National Crime Victimization Survey and School Crime Supplement to the survey, sponsored by the BJS and NCES, respectively; the Youth Risk Behavior Survey, sponsored by the Centers for Disease Control and Prevention; and the Schools and Staffing Survey and School Survey on Crime and Safety, both sponsored by NCES. The most recent data collection for each indicator varied by survey, from 2007 to 2011. Each data source has an independent sample design, data collection method, and questionnaire design, or is the result of a universe data collection. All comparisons described in this report are statistically significant at the .05 level. Additional information about methodology and the datasets analyzed in this report may be found in appendix A. This report covers topics such as victimization, teacher injury, bullying and cyber-bullying, school conditions, fights, weapons, availability and student use of drugs and alcohol, and student perceptions of personal safety at school. Indicators of crime and safety are compared across different population subgroups and over time. Data on crimes that occur away from school are offered as a point of comparison where available

    Thermal expansion and Gruneisen parameters in some Pr–Ni–Si compounds

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    In this study, the thermal expansion and Gruneisen parameter of polycrystalline “Pr5Ni2Si3” and “Pr15Ni7Si10” were investigated over the temperature range of 5–300 K. Calculations of the phonon contribution to thermal expansion were made, which allowed the magnetic contribution to thermal expansion to be calculated from the difference between the total thermal expansion and the phonon contribution. This resulted in a temperature-dependent magnetic contribution to thermal expansion that varied with the magnetic ordering of the material. The results show two magnetic transitions in each compound, the higher temperature transition corresponding to the Curie temperature and the lower temperature transition resulting from a spin reorientation

    Cladding mode coupling in highly localized fiber Bragg gratings: modal properties and transmission spectra

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    The spectral characteristics of a fiber Bragg grating (FBG) with a transversely inhomogeneous refractive index profile, differs con- siderably from that of a transversely uniform one. Transmission spectra of inhomogeneous and asymmetric FBGs that have been inscribed with focused ultrashort pulses with the so-called point-by-point technique are investigated. The cladding mode resonances of such FBGs can span a full octave in the spectrum and are very pronounced (deeper than 20dB). Using a coupled-mode approach, we compute the strength of resonant coupling and find that coupling into cladding modes of higher azimuthal order is very sensitive to the position of the modification in the core. Exploiting these properties allows precise control of such reflections and may lead to many new sensing applications.Comment: Submission to OE, 16 pages, 6 figure

    The Effects of Background Pressure on SPT-140 Thruster Performance at Multiple Power Levels

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    NASA's planned Psyche mission is scheduled to launch in 2022 and begin a 3.5-year cruise to the metallic asteroid Psyche, where it would examine this unique body. The baseline spacecraft design is a hybrid of JPL's deep-space heritage subsystems with commercial partner SSL's power, structure, and SPT-140 electric propulsion subsystems. Since the deep-space implementation of the SPT-140 differs from the commercial implementation, primarily in the need for deep power throttling, characterization of the system at lower powers is necessary. One specific area of interest is the sensitivity of thruster performance to background pressure in ground-based test facilities, which can have an impact on the prediction of in-space performance. Measurements of this pressure dependence were performed on a qualification-model SPT-140 thruster over the 0.9-4.5 kW range of interest for the Psyche mission. Thrust sensitivity to pressure, in an absolute sense, was largest at 4.5 kW and decreased with power until there was little-to-no measurable effect at 0.9 kW. In a relative sense, thrust sensitivity was similar at all powers above 0.9 kW with about 2-4% higher thrust measured at 10 Torr than at the lowest operating pressure. Thruster stability margin, examined as a function of magnet current, did not have a strong dependence on facility pressure. Finally, an investigation of low-power operation at the lowest facility pressure showed that a combination of added cathode keeper current and additional cathode propellant flow significantly mitigated the larger negative cathode-to-ground voltages that were observed. These test results, combined with thruster life test results, inform the selection of proper low-power operating conditions for Psyche

    Catalog of selected heavy duty transport energy management models

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    A catalog of energy management models for heavy duty transport systems powered by diesel engines is presented. The catalog results from a literature survey, supplemented by telephone interviews and mailed questionnaires to discover the major computer models currently used in the transportation industry in the following categories: heavy duty transport systems, which consist of highway (vehicle simulation), marine (ship simulation), rail (locomotive simulation), and pipeline (pumping station simulation); and heavy duty diesel engines, which involve models that match the intake/exhaust system to the engine, fuel efficiency, emissions, combustion chamber shape, fuel injection system, heat transfer, intake/exhaust system, operating performance, and waste heat utilization devices, i.e., turbocharger, bottoming cycle

    American Higher Education in Transition

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    Political strategies of external support for democratization

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    Political strategies of external support to democratization are contrasted and critically examined in respect of the United States and European Union. The analysis begins by defining its terms of reference and addresses the question of what it means to have a strategy. The account briefly notes the goals lying behind democratization support and their relationship with the wider foreign policy process, before considering what a successful strategy would look like and how that relates to the selection of candidates. The literature's attempts to identify strategy and its recommendations for better strategies are compared and assessed. Overall, the article argues that the question of political strategies of external support for democratization raises several distinct but related issues including the who?, what?, why?, and how? On one level, strategic choices can be expected to echo the comparative advantage of the "supporter." On a different level, the strategies cannot be divorced from the larger foreign policy framework. While it is correct to say that any sound strategy for support should be grounded in a theoretical understanding of democratization, the literature on strategies reveals something even more fundamental: divergent views about the nature of politics itself. The recommendations there certainly pinpoint weaknesses in the actual strategies of the United States and Europe but they have their own limitations too. In particular, in a world of increasing multi-level governance strategies for supporting democratization should go beyond preoccupation with just an "outside-in" approach

    Distinct cortical and striatal actions of a β-arrestin-biased dopamine D2 receptor ligand reveal unique antipsychotic-like properties.

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    The current dopamine (DA) hypothesis of schizophrenia postulates striatal hyperdopaminergia and cortical hypodopaminergia. Although partial agonists at DA D2 receptors (D2Rs), like aripiprazole, were developed to simultaneously target both phenomena, they do not effectively improve cortical dysfunction. In this study, we investigate the potential for newly developed β-arrestin2 (βarr2)-biased D2R partial agonists to simultaneously target hyper- and hypodopaminergia. Using neuron-specific βarr2-KO mice, we show that the antipsychotic-like effects of a βarr2-biased D2R ligand are driven through both striatal antagonism and cortical agonism of D2R-βarr2 signaling. Furthermore, βarr2-biased D2R agonism enhances firing of cortical fast-spiking interneurons. This enhanced cortical agonism of the biased ligand can be attributed to a lack of G-protein signaling and elevated expression of βarr2 and G protein-coupled receptor (GPCR) kinase 2 in the cortex versus the striatum. Therefore, we propose that βarr2-biased D2R ligands that exert region-selective actions could provide a path to develop more effective antipsychotic therapies
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