705 research outputs found

    The Dormant Second Amendment: Exploring the Rise, Fall, and Potential Resurrection of Independent State Militias

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    The term “militia” is polarizing, misunderstood, misapplied, and generally difficult for modern Americans to digest. That is not surprising, given the depth and breadth of American militia history and militias’ substantial evolution over four centuries. Historically, militia simply refers to a broad-based civic duty to protect one’s fellow citizens from internal and external dangers and is not limited to activities involving firearms. Reestablishing militia’s true meaning and purpose—and reinvigorating independent state militias in the United States to effect that purpose—has the potential to address states’ emerging financial and security gaps and to produce multiple other significant benefits, including recalibrating federalism. This article suggests a method for how best to reinvigorate independent state militias, addresses the major critique against doing so, and initiates a real discussion about the future of state militias—an issue conspicuously underdeveloped in scholarship today

    Agency Theory Issues in the Food Processing Industry

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    The objective is to identify significant determinants of performance for food processing firms over the 1992 to 2003 time period, focusing particularly on the issue of family control. Variables measuring firm effects such as asset size, governance, income distribution, and risk are used to explain return on equity. This study builds upon previous research by including a measure of income distribution in the food processing industry. Governance variables are found to be significant determinants of return on equity. The results found no evidence of agency problems in family-controlled firms during this time period.agribusiness, institutional economics, organizational economics, Agribusiness, Food Consumption/Nutrition/Food Safety, Production Economics, D23, G34, Q13, Q14,

    Spacecraft Materials in the Space Flight Environment: International Space Station - May 2002 to May 2007

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    The performance of ISS spacecraft materials and systems on prolonged exposure to the low-Earth orbit (LEO) space flight is reported in this paper. In-flight data, flight crew observations, and the results of ground-based test and analysis directly supporting programmatic and operational decision-making are presented. The space flight environments definitions (both natural and induced) used for ISS design, material selection, and verification testing are shown, in most cases, to be more severe than the actual flight environment accounting for the outstanding performance of ISS as a long mission duration spacecraft. No significant ISS material or system failures have been attributed to spacecraft-environments interactions. Nonetheless, ISS materials and systems performance data is contributing to our understanding of spacecraft material interactions in the spaceflight environment so as to reduce cost and risk for future spaceflight projects and programs. Orbital inclination (51.6o) and altitude (nominally near 360 km) determine the set of natural environment factors affecting the functional life of materials and systems on ISS. ISS operates in an electrically conducting environment (the F2 region of Earth s ionosphere) with well-defined fluxes of atomic oxygen, other charged and neutral ionospheric plasma species, solar UV, VUV, and x-ray radiation as well as galactic cosmic rays, trapped radiation, and solar cosmic rays (1-4). The LEO micrometeoroid and orbital debris environment is an especially important determinant of spacecraft design and operations (5, 6). The magnitude of several environmental factors varies dramatically with latitude and longitude as ISS orbits the Earth (1-4). The high latitude orbital environment also exposes ISS to higher fluences of trapped energetic electrons, auroral electrons, solar cosmic rays, and galactic cosmic rays (1-4) than would be the case in lower inclination orbits, largely as a result of the overall shape and magnitude of the geomagnetic field (1-4). As a result, ISS exposure to many environmental factors can vary dramatically along a particular orbital ground track, and from one ground track to the next, during any 24-hour period

    Research and education in management of large-scale technical programs

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    A research effort is reported which was conducted by NASA in conjunction with Drexel University, and which was aimed at an improved understanding of large scale systems technology and management

    Electroweak Corrections in Technicolor Reconsidered

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    Radiative corrections to electroweak parameters in technicolor theories may be evaluated by one of two techniques: either one estimates spectral function integrals using scaled QCD data, or one uses naive dimensional analysis with a chiral Lagrangian. The former yields corrections to electroweak parameters proportional to the number of flavors and the number of colors, while the latter is proportional to the number of flavors squared and is independent of the number of colors. We attempt to resolve this apparent contradiction by showing that the spectrum of technicolor one obtains by scaling QCD data to high energies is unlikely to resemble that of an actual technicolor theory. The resonances are likely to be much lighter than naively supposed and the radiative corrections to electroweak parameters may by much larger. We also argue that much less is known about the spectrum and the radiative corrections in technicolor than was previously believed.Comment: 17 pages (which incl 3 figures), BUHEP-92-25 HUTP-92/A033, text uses harvmac, figures use picte

    NADPH oxidase deficiency results in reduced alveolar macrophage 5â lipoxygenase expression and decreased leukotriene synthesis

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141933/1/jlb1585.pd

    Using Farm Practice Variables as Predictors of Listeria spp. Prevalence in Pastured Poultry Farms

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    Predictive models offer food scientists, farmers, and processors tools to help identify variables that lead to an increase in the food safety risk of a product. Foodborne pathogens, such as Listeria spp., pose a major problem for the pastured poultry industry. Currently, there is a lack of understanding of what farm practices lead to higher prevalence of Listeria spp. This study constructed random forest (RF) models to predict the prevalence of Listeria spp. in pastured poultry farming environments and the final broiler product based on major farm practices and variables. Feces, soil, and whole carcass rinse samples were collected from 11 farms in the southeastern United States and evaluated for Listeria spp. presence. The preharvest sample RF model identified the time of year and age of the broiler flock at time of sampling as factors of increased probability of Listeria spp. presence in feces and soil samples. The final product RF model identified brood feed and the presence of chlorine in processing rinse water as the two most important variables associated with an increased likelihood of Listeria spp. presence. Both the preharvest RF model and final sample RF model performed well on a held-out test set, with area under the receiver operating characteristic curve values of 0.876 and 0.887, respectively. The presented models showed the usefulness of RF models in a food safety context. Both RF models will help pastured poultry farmers and processors guide control strategies to manage Listeria contamination in pastured poultry farms and products

    Cosmic-Ray Positrons: Are There Primary Sources?

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    Cosmic rays at the Earth include a secondary component originating in collisions of primary particles with the diffuse interstellar gas. The secondary cosmic rays are relatively rare but carry important information on the Galactic propagation of the primary particles. The secondary component includes a small fraction of antimatter particles, positrons and antiprotons. In addition, positrons and antiprotons may also come from unusual sources and possibly provide insight into new physics. For instance, the annihilation of heavy supersymmetric dark matter particles within the Galactic halo could lead to positrons or antiprotons with distinctive energy signatures. With the High-Energy Antimatter Telescope (HEAT) balloon-borne instrument, we have measured the abundances of positrons and electrons at energies between 1 and 50 GeV. The data suggest that indeed a small additional antimatter component may be present that cannot be explained by a purely secondary production mechanism. Here we describe the signature of the effect and discuss its possible origin.Comment: 15 pages, Latex, epsfig and aasms4 macros required, to appear in Astroparticle Physics (1999

    S-Band Transponder Multi-Network Compatibility, Space Environment and Radiation Testing

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    This paper presents the development and testing of the Software Define Radio (SDR) transceiver to meet the emerging needs for SmallSat communication and navigation. Vulcan Wireless and NASA Goddard Space Flight Center (GSFC) collaborated in testing the Vulcan Wireless S-band SDR engineering model. Apart from testing, communication link analysis was performed for a Low Earth Orbit (LEO) 400 km scenario. The results of the compatibility, radiation, environmental testing, and link analysis are presented. Also, this paper reviews a set of SmallSat missions under development at NASA GSFC
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