740 research outputs found

    Production Risk and Crop Insurance Effectiveness: Organic Versus Conventional Apples

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    This paper empirically examines the income risks for Pacific Northwest apple growers, both conventional and organic. Current yield based apple production insurance, the Growers Yield Certification (GYC), and hypothesized revenue based insurance are also examined for their risk management effect on growers. Results show that organic apple production is more risky but has higher expected return than its conventional counterpart. The current GYC is subsidized and subsidized more for organic growers. However, the current low price selection levels prevent these programs from offering effective risk reducing effect, and they also prevent the hypothesized revenue insurance from showing its advantage over yield insurance as in the case of other major field crops.Risk and Uncertainty,

    THE CROWDING OUT EFFECTS OF THE 2002 FARM BILL ON HEDGING: EVIDENCE FROM PACIFIC NORTHWEST GRAIN FARMS

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    The 2002 Food Security and Rural Investment (FSRI) Act introduced a price protection program called Counter Cyclical Payments (CCP) to major grain producers in the US. The CCP program is an addition to the Loan Deficiency Payment (LDP) and Direct Payment (DP) programs from the previous 1996 Federal Agriculture Improvement and Reform (FAIR) Act. At the same time, US federally subsidized crop revenue insurance programs also protect farmers from market and production risks. These government policy programs may crowd out the traditional price risk management role of hedging in commodity futures markets.Agricultural and Food Policy, Crop Production/Industries,

    EVALUATING RISK MANAGEMENT STRATEGIES FOR NON-IRRIGATED SMALL GRAIN PRODUCERS

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    Risk management strategies (market and insurance based) are evaluated for selected small grain producers in the Pacific Northwest using expected utility maximization. Equivalent variation (EV) compares alternative risk management portfolios to cash sales under specified restrictions and conditions. Resulting EV's are strongly influenced by government payments, and hedging-based strategies are not used when counter cyclical payments are included in government programs. Optimum risk management portfolios include extensive coverage by insurance-based products only when such products have premiums that are heavily subsidized, or have premiums with no significant expense load.Risk and Uncertainty,

    Effectiveness of Surface Treatment Techniques for Composite Bonding with Different Contamination Levels

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    Various surface treatment techniques have been developed to promote adhesive bond performance for composite structural components in aerospace applications. The condition of the pre-bond surface is critical to achieving desirable bond quality. Contamination on bonding surfaces is well recognized as a major threat to ultimate bond performance. Variation in contamination level has brought additional challenges into manufacturing process control. High fidelity surface treatment techniques are required for effective removal of contaminants over a wide range of contamination levels. In this study, a common contaminant, i.e. silicone mold release, was introduced to pre-bond composite surfaces with different concentrations. Plasma and laser surface treatment techniques were performed and their effectiveness in restoring and enhancing desirable bond quality was investigated. Surface characterization techniques, including water contact angle goniometry, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, were conducted to assess the condition of contaminated surfaces and the improvement induced by plasma and laser surface treatments. Failure modes from a customized double cantilever beam test were investigated before and after surface treatments. Fundamental mechanisms of plasma and laser surface treatments on the composite bonding surfaces were also investigated

    Surface charge deposition by moving drops reduces contact angles

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    Slide electrification - the spontaneous charge separation by sliding water drops - can lead to an electrostatic potential of 1 kV and change drop motion substantially. To find out, how slide electrification influences the contact angles of moving drops, we analyzed the dynamic contact angles of aqueous drops sliding down tilted plates with insulated surfaces, grounded surfaces, and while grounding the drop. The observed decrease in dynamic contact angles at different salt concentrations is attributed to two effects: An electrocapillary reduction of contact angles caused by drop charging and a change in the free surface energy of the solid due to surface charging

    Characterization of Maternal and Fetal CYP3A-Mediated Progesterone Metabolism

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    INTRODUCTION: Progesterone is critical for maintaining pregnancy and onset of labor. We evaluated CYP450-mediated progesterone meta-bolism, specifically the contribution of CYP3A isoforms. MATERIALS AND METHODS: In vitro progesterone metabolism was characterized in human liver microsomes (HLMs) with and without selective cytochrome P450 inhibitors and in recombinant CYP3A4, CYP3A5, and CYP3A7. 6β-hydroxyprogesterone (6β-OHP) and 16α-hydroxyprogesterone (16α-OHP) metabolites were quantified by HPLC/UV and fit to the Michaelis-Menten equation to determine Km and Vmax. The effect of CYP3A5 expression on progesterone clearance was determined by in vitro in vivo extrapolation. RESULTS: Ketoconazole inhibited formation of both 6β-OHP and 16α-OHP more than 95%. 6β-OHP and 16α-OHP were both produced by CYP3A4 (2.3 and 1.3 µL/min/pmol, respectively) to a greater extent than by CYP3A5 (0.09 and 0.003 µL/min/pmol) and CYP3A7 (0.004 and 0.003 µL/min/pmol). CONCLUSIONS: Maternal clearance of progesterone by hepatic CYP450's is driven primarily by CYP3A4, with limited contributions from CYP3A5 and CYP3A7

    Receiver Operating Characteristic and Location Analysis of Simulated Near-Infrared Tomography Images

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    Receiver operating characteristic (ROC) analysis was performed on simulated near-infrared tomography images, using both human observer and contrast-to-noise ratio (CNR) computational assessment, for application in breast cancer imaging. In the analysis, a nonparametric approach was applied for estimating the ROC curves. Human observer detection of objects had superior capability to localize the presence of heterogeneities when the objects were small with high contrast, with a minimum detectable threshold of CNR near 3.0 to 3.3 in the images. Human observers were able to detect heterogeneities in the images below a size limit of 4 mm, yet could not accurately find the location of these objects when they were below 10 mm diameter. For large objects, the lower limit of a detectable contrast limit was near 10% increase relative to the background. The results also indicate that iterations of the nonlinear reconstruction algorithm beyond 4 did not significantly improve the human detection ability, and degraded the overall localization ability for the objects in the image, predominantly by increasing the noise in the background. Interobserver variance performance in detecting objects in these images was low, suggesting that because of the low spatial resolution, detection tasks with NIR tomography is likely consistent between human observers

    Ultra-bright, ultra-broadband hard x-ray driven by laser-produced energetic electron beams

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    We propose a new method of obtaining a compact ultra-bright, ultra-broadband hard X-ray source. This X-ray source has a high peak brightness in the order of 1022 photons/(s mm2 mrad2 0.1\%BW), an ultrashort duration (10 fs), and a broadband spectrum (flat distribution from 0.1 MeV to 4 MeV), and thus has wide-ranging potential applications, such as in ultrafast Laue diffraction experiments. In our scheme, laser-plasma accelerators (LPAs) provide driven electron beams. A foil target is placed oblique to the beam direction so that the target normal sheath field (TNSF) is used to provide a bending force. Using this TNSF-kick scheme, we can fully utilize the advantages of current LPAs, including their high charge, high energy, and low emittance

    Synthesis and Antibacterial Property of An Encapsulated Sulfonamide Nanoparticle in a Multidisciplinary Approach

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    Multigram quantity of a novel Sulfa Drug complex -poly(amido)amine-sulfonamide or PAMAM-Sulfa- was synthesized, from commercially available materials. It was characterized with spectroscopic methods such as nuclear magnetic resonance (NMR). The Kirby-Bauer test was used to test it against gram positive and/or gram negative bacteria using different concentrations of an ethanol solution of the PAMAM-Sulfa complex. The goal of this experiment was to synthesize and study the effect of water soluble encapsulated sulfonamides on common bacteria by undergraduate students engaging in research involving more than one STEM discipline. Students synthesized a dendrimer-sulfonamide complex before evaluating its antibiotic properties. In doing so, students employed research methods that are common to chemistry, biology and nanoscience while also learning about mechanism of infectious diseases, drugs and drug resistance. This project allowed students to combine aspects of scientific research that are usually done separately, and an opportunity to observe the seamlessness of multidisciplinary science
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