1,217 research outputs found

    Contracting Out Government Procurement Functions: An Analysis

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    Proceedings Paper (for Acquisition Research Program)The Deputy Assistant Secretary of the Navy for Research, Development & Acquisition (DASN (RDA) (Acquisition Management)), asked the Naval Postgraduate School (NPS) to analyze the contracting out of procurement functions currently being accomplished by Navy, Marine Corps, and other Department of Defense (DOD) Activities. The request specifically focused on assessing the degree of effectiveness and shortcomings of such contracting out efforts. This research sought to answer these questions: Which contracting functions are now being contracted out by Navy and other DOD organizations? How effectively have contractors performed on these contracts? What metrics are being used and could be used to assess the quality of contractor performance? Although the primary focus of this study is the effectiveness of contracts used to procure contracting services, several interrelated subjects have been explored. Aspects of inherently governmental functions, personal service relationships, conflicts of interest, and legal/ethical issues were included. Further, questions regarding the impact on the contracting system, the development of Contracting Officers, the participation of competing companies in the marketplace, training and experience qualifications, and agency procurement decision-making and policies were also examined.Naval Postgraduate School Acquisition Research ProgramApproved for public release; distribution is unlimited

    Economic tradeoff between biochar and bio-oil production via pyrolysis

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    This paper examines some of the economic tradeoffs in the joint production of biochar and bio-oil from cellulosic biomass. The pyrolysis process can be performed with different final temperatures, and with different heating rates. While most carbonization technologies operating at low heating rates result in higher yields of charcoal, fast pyrolysis is the technology of choice to produce bio-oils. Varying operational and design parameters can change the relative quantity and quality of biochar and bio-oil produced for a given feedstock. These changes in quantity and quality of both products affect the potential revenue from their production and sale. We estimate quadratic production functions for biochar and bio-oil. The results are then used to calculate a product transformation curve that characterizes the yields of bio-oil and biochar that can be produced for a given amount of feedstock, movement along the curve corresponds to changes in temperatures, and it can be used to infer optimal pyrolysis temperature settings for a given ratio of biochar and bio-oil prices.biochar, bio-oil, pyrolysis, biomass conversion, economic tradeoff

    Renal endothelial dysfunction in acute kidney ischemia reperfusion injury

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    Acute kidney injury is associated with alterations in vascular tone that contribute to an overall reduction in GFR. Studies in animal models indicate that ischemia triggers alterations in endothelial function that contribute significantly to the overall degree and severity of a kidney injury. Putative mediators of vasoconstriction that may contribute to the initial loss of renal blood flow and GFR are highlighted. In addition, there is discussion of how intrinsic damage to the endothelium impairs homeostatic responses in vascular tone as well as promotes leukocyte adhesion and exacerbating the reduction in renal blood flow. The timing of potential therapies in animal models as they relate to the evolution of AKI, as well as the limitations of such approaches in the clinical setting are discussed. Finally, we discuss how acute kidney injury induces permanent alterations in renal vascular structure. We posit that the cause of the sustained impairment in kidney capillary density results from impaired endothelial growth responses and suggest that this limitation is a primary contributing feature underlying progression of chronic kidney disease

    EMPLOYER SIZE, HUMAN CAPITAL, AND RURAL WAGES: IMPLICATIONS FOR SOUTHERN RURAL DEVELOPMENT

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    A recent trend in rural development policy emphasizes small business development in place of industrial recruitment. To analyze some of the likely effects of expanding the proportion of small firms in local economies, an empirical wage rate model incorporating employer size was developed, and parameters were estimated using household date from rural Putnam County, Georgia. The estimates indicated that large employers offered higher wages than small employers and that the wage premium they offered was greater for blacks than for whites. These results support Thomas Till's argument that southern rural counties with relatively large black populations should not abandon efforts to attract large employers. Other factors associated with higher wages included level of education, previous labor force experience, and employment in certain occupations and industries.Community/Rural/Urban Development, Labor and Human Capital,

    The Economic Value of Biochar in Crop Production and Carbon Sequestration

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    This paper estimates the economic value of biochar application on agricultural cropland for carbon sequestration and its soil amendment properties. In particular, we consider the carbon emissions avoided when biochar is applied to agricultural soil, instead of agricultural lime, the amount of carbon sequestered, and the value of carbon offsets, assuming there is an established carbon trading mechanism for biochar soil application. We use winter wheat production in Eastern Whitman County, Washington as a case study, and consider different carbon offset price scenarios and different prices of biochar to estimate a farm profit. Our findings suggest that it may be profitable to apply biochar as a soil amendment under some conditions if the biochar market price is low enough and/or a carbon offset market exists.Biochar, Carbon sequestration, Crop, Farm profitability, Soil amendment

    Angle-Resolved Photoemission of Solvated Electrons in Sodium-Doped Clusters

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    Angle-resolved photoelectron spectroscopy of the unpaired electron in sodium-doped water, methanol, ammonia, and dimethyl ether clusters is presented. The experimental observations and the complementary calculations are consistent with surface electrons for the cluster size range studied. Evidence against internally solvated electrons is provided by the photoelectron angular distribution. The trends in the ionization energies seem mainly determined by the degree of hydrogen bonding in the solvent and the solvation of the ion core. The onset ionization energies of water and methanol clusters do not level off at small cluster sizes, but decrease slightly with increasing cluster size

    Cofilin Activation in Peripheral CD4 T Cells of HIV-1 Infected Patients: A Pilot Study

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    Cofilin is an actin-depolymerizing factor that regulates actin dynamics critical for T cell migration and T cell activation. In unstimulated resting CD4 T cells, cofilin exists largely as a phosphorylated inactive form. Previously, we demonstrated that during HIV-1 infection of resting CD4 T cells, the viral envelope-CXCR4 signaling activates cofilin to overcome the static cortical actin restriction. In this pilot study, we have extended this in vitro observation and examined cofilin phosphorylation in resting CD4 T cells purified from the peripheral blood of HIV-1-infected patients. Here, we report that the resting T cells from infected patients carry significantly higher levels of active cofilin, suggesting that these resting cells have been primed in vivo in cofilin activity to facilitate HIV-1 infection. HIV-1-mediated aberrant activation of cofilin may also lead to abnormalities in T cell migration and activation that could contribute to viral pathogenesis.Department of Defense (National Defense Science and Engineering Fellowship); National Institute of Allergy and Infectious Diseases (AI069981

    PRIOR REGULATION AND POST LIABILITY AS COMPLEMENTS: AN APPLICATION TO PRESCRIBED BURNING LAW IN THE UNITED STATES

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    Prescribed burning is increasingly being recognized as a useful land management and conservation tool, but with it comes the risk of fire and smoke damage to the property of others. All but two states have codified laws specifying criminal penalties or liability rules for prescribed burning, but the laws in a number of states have changed in recent years or are under review. We develop an economic model of the incentive and welfare effects of prescribed burning and the use of prior regulation and post liability as instruments to address potential external damage from the use of prescribed fire.Resource /Energy Economics and Policy,

    Anti-angiogenic activity of kidney derived endothelial cells

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    poster abstractThe identification of novel endogenous mediators of angiogenic/vasculogenic processes may provide for novel therapeutic targets to modulate blood vessel growth in disease states, such as cardiovascular disease or cancer. Studies in our lab have shown that blood vessels in kidney have little endogenous regenerative capacity. Kidney derived microvascular endothelial cells (KEC) were isolated from rat kidney or from transgenic mice bearing the temperature sensitive SV40 mutant (and subsequently grown at non-permissive temperature, 37oC). Both rat and mouse KECs manifested significantly reduced growth rates when compared with several commonly used EC lines (rat pulmonary EC, HUVEC and human cord blood colony forming ECs). In 2D matrigel assays, all commonly used ECs faithfully formed characteristic branching structures; while all KECs failed to form stabile branching structures. Time-course analysis of branching activity demonstrated that KEC initially formed primitive branching nodes within 3 hours of culture, but these structures regressed such that no branched structures were observed between 6-12 hours. Co-culture of KECs with any branching competent EC impaired branching dose dependently. When co-cultured with ECFC, labeled KECs incorporated into primitive ECFC branches within the first 3 hours of plating. However, when compared with ECFC branches, ECFC-KEC mixed branches showed a more rapid regression of the branched structures between 12-24 hrs. Interestingly, conditioned media from KEC did not affect branching of competent ECFC. Taken together, these data indicate that KEC have anti-angiogenic activity that may destabilize ECs during angiogenesis. The anti-angiogenic activity requires cell-cell contact, suggesting the possible presence of an angio-inhibitory molecule on the cell surface of KECs. Current and future studies seek to generate additional KEC lines, and will determine if KEC cell fractions mediate the anti-angiogenic effect. In addition, we will seek to determine if KECs mitigate progression of angiogenic dependent tumor formation in vivo

    Report of the panel on earth structure and dynamics, section 6

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    The panel identified problems related to the dynamics of the core and mantle that should be addressed by NASA programs. They include investigating the geodynamo based on observations of the Earth's magnetic field, determining the rheology of the mantle from geodetic observations of post-glacial vertical motions and changes in the gravity field, and determining the coupling between plate motions and mantle flow from geodetic observations of plate deformation. Also emphasized is the importance of support for interdisciplinary research to combine various data sets with models which couple rheology, structure and dynamics
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