315 research outputs found
Orderly Marketing in Agriculture Revisited
This paper presents a model of economic behavior that explicates the phenomenon known as ĂąâŹĆorderly marketing,ù⏠which was a main objective of the Marketing Orders agricultural program introduced early in the New Deal. Recent analyses of marketing orders start with an implicit assumption that there is no market failureĂąâŹâthus, that price regulation can cause only deviations from the first-best market solution. However, historical evidence suggests that disorderly marketing might refer to a kind of market imperfection. In the model presented here, a monopsonist processor sets a price to be paid, and an aggregate quantity to be purchased. In some states of the world, some farmers are excluded from the market. In other words, nonprice rationing can occur, and changes in consumer expenditure for the final product are absorbed by the processor rather than passed along to the farmer. The classified price and pooling provisions of federal orders can lead to a Pareto improvement in welfare.disorderly marketing, market orders, Marketing,
Are Cooperatives Efficient When Membership is Voluntary?
If profit-maximizing farmers are free to join or not to join a cooperative, it may appear reasonable to assume that a cooperative will exist only when it has cost advantaged over non-cooperative marketing. This paper presents a model in which that result fails. Every individual farmer chooses either to join or not join a cooperative depending on whether transactions costs are lower from cooperative membership or nonmembership. As cooperative membership increases, transactions costs for members decline, but for nonmembers these costs increase. Results of this analysis reveal that an equilibrium exists in which all farmers voluntarily choose to join the cooperative, but more than half of the members wish the cooperative had not been formed, and transactions costs in the aggregate are higher with the cooperative then without it.cooperatives, transactions costs, Agribusiness,
A PRIMER ON NUTRITION POLICY IN THE UNITED STATES
Agricultural and Food Policy, Food Consumption/Nutrition/Food Safety,
The economics of farm accidents and safety in New Zealand agriculture
This report presents an economic analysis of farm accidents in New Zealand. Presently, the social costs of farm accidents are not well understood: their monetary importance to the farmer, hence the nation,has thus far not been quantified in a way meaningful to safety policy makers. Information about the relative magnitude of social costs resulting from accidents on farms is necessary to establish the potential social benefits attributable to safety. Such information is
required if safety expenditures are to be rationally allocated to priority needs
Farmland pricing in an inflationary economy with implications for public policy
While the importance of the price of land in agricultural
production and policy is well recognised, land price formation is a
process not well understood.
The study reported here was aimed at an examination of the cause
and implications of farmland price inflation in New Zealand over the
past 20 or so years. The report attempts to isolate some of the
factors other than annual earnings that could explain the sudden
increase in the market value of farmland during an inflationary period.Ministry of
Agriculture and Fisherie
Immersed Boundary Double Layer Method
The Immersed Boundary (IB) method of Peskin (J. Comput. Phys., 1977) is
useful for problems involving fluid-structure interactions or complex
geometries. By making use of a regular Cartesian grid that is independent of
the geometry, the IB framework yields a robust numerical scheme that can
efficiently handle immersed deformable structures. Additionally, the IB method
has been adapted to problems with prescribed motion and other PDEs with given
boundary data. IB methods for these problems traditionally involve penalty
forces which only approximately satisfy boundary conditions, or they are
formulated as constraint problems. In the latter approach, one must find the
unknown forces by solving an equation that corresponds to a poorly conditioned
first-kind integral equation. This operation can require a large number of
iterations of a Krylov method, and since a time-dependent problem requires this
solve at each time step, this method can be prohibitively inefficient without
preconditioning. In this work, we introduce a new, well-conditioned IB
formulation for boundary value problems, which we call the Immersed Boundary
Double Layer (IBDL) method. We present the method as it applies to Poisson and
Helmholtz problems to demonstrate its efficiency over the original constraint
method. In this double layer formulation, the equation for the unknown boundary
distribution corresponds to a well-conditioned second-kind integral equation
that can be solved efficiently with a small number of iterations of a Krylov
method. Furthermore, the iteration count is independent of both the mesh size
and immersed boundary point spacing. The method converges away from the
boundary, and when combined with a local interpolation, it converges in the
entire PDE domain. Additionally, while the original constraint method applies
only to Dirichlet problems, the IBDL formulation can also be used for Neumann
conditions
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Tibial Tubercle Osteotomy and Medial Patellofemoral Ligament Imbrication for Patellar Instability Due to Trochlear Dysplasia.
BackgroundThe treatment of patellar instability in the setting of trochlear dysplasia is challenging.Purpose/hypothesisThe purpose of this study was to evaluate outcomes for the treatment of recurrent patellar dislocations due to trochlear dysplasia using anteromedialization tibial tubercle osteotomy combined with medial patellofemoral ligament (MPFL) imbrication. We hypothesized that the treatment of patellar instability with tibial tubercle osteotomy and MPFL imbrication would result in improved patient satisfaction and decrease patellar instability events in patients with prior instability and trochlear dysplasia.Study designCase series; Level of evidence, 4.MethodsWe performed a retrospective analysis of patients who underwent MPFL imbrication and concomitant anteromedialization tibial tubercle osteotomy for recurrent patellofemoral instability at a single institution. The minimum follow-up was 1 year. Patient demographic information including age at the time of surgery, sex, body mass index (BMI), tibial tubercle-trochlear groove (TT-TG) distance, and grade of trochlear dysplasia was collected along with relevant operative data. Postoperatively, recurrent dislocation events as well as Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index, and Kujala scores were collected, and satisfaction was ascertained by asking patients whether they would undergo the procedure again.ResultsA total of 37 knees from 31 patients (23 female) with a mean follow-up of 3.8 years (range, 1-8.9 years) were included. The mean patient age was 28.8 years (range, 14-45 years), the mean BMI was 24 kg/m2 (range, 20-38 kg/m2), and the mean preoperative TT-TG distance was 18.9 mm (range, 8.4-32.4 mm). Two knees were classified as low-grade trochlear dysplasia (Dejour A) and 35 as high-grade trochlear dysplasia (Dejour B-D). At final follow-up, patients reported mean KOOS subscale scores of 86.5 (Pain), 79.8 (Symptoms), 93.9 (Activities of Daily Living), 74.3 (Sports/Recreation), and 61.9 (Quality of Life), as well as a mean Kujala score of 81.3. Mean patient satisfaction was 8.3 of 10. The majority of knees (86.5%; 32/37) remained stable without recurrent instability after this procedure, while 13.5% (5 knees) suffered a recurrent dislocation, with 2 requiring revision surgery. Eight knees (21.6%) underwent subsequent hardware removal.ConclusionAnteromedialization tibial tubercle osteotomy with MPFL imbrication can improve recurrent patellofemoral instability and provide significant clinical benefit to patients with trochlear dysplasia
Complete Genome Sequence of \u3ci\u3eLactobacillus buchneri\u3c/i\u3e NRRL B-30929, a Novel Strain from a Commercial Ethanol Plant
Lactobacillus buchneri strain NRRL B-30929 was a contaminant obtained from a commercial ethanol fermentation. This facultative anaerobe is unique because of its rapid growth on xylose and simultaneous fermentation of xylose and glucose. The strain utilizes a broad range of carbohydrate substrates and possesses a high tolerance to ethanol and other stresses, making it an attractive candidate for bioconversion of biomass substrates to various bioproducts. The genome sequence of NRRL B-30929 will provide insight into the unique properties of this lactic acid bacterium
Evaluation of rapid diagnostic tests for assessment of hepatitis B in resource-limited settings
Chronic Hepatitis B (HBV) is the most important cause of liver disease worldwide. There is a need for low-cost tests to aid in diagnosis and management of HBV infection in resource-limited settings. We evaluated the utility of several rapid diagnostic tests (RDT) in three different continents (Europe, South America, Africa). The HBsAg RDT showed optimal sensitivity and specificity. The anti-HBeAb RDT showed acceptable sensitivity and excellent specificity. Our results suggest that these RDTs could be used for screening and management of HBV.Fil: Leathers, James S.. Uc Davis School Of Medicine; Estados UnidosFil: Pisano, MarĂa BelĂ©n. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de CĂłrdoba. Facultad de Medicina. Instituto de VirologĂa Dr. J. M. Vanella; ArgentinaFil: RĂ©, Viviana Elizabeth. Universidad Nacional de CĂłrdoba. Facultad de Medicina. Instituto de VirologĂa Dr. J. M. Vanella; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Van Oord, Gertine. Erasmus MC. Department of Gastroenterology and Hepatology; PaĂses BajosFil: Sultan, Amir. Addis Ababa University; EtiopĂaFil: Boonstra, Andre. Erasmus MC. Department of Gastroenterology and Hepatology; PaĂses BajosFil: Debes, Jose D.. University of Minnesota; Estados Unidos. Erasmus MC. Department of Gastroenterology and Hepatology; PaĂses Bajo
Validation of a point-of-care rapid diagnostic test for hepatitis C for use in resource-limited settings
Treatment of HCV with direct-acting antivirals has enabled the discussion of HCV eradicationworldwide. Envisioning this aim requires implementation of mass screening in resource-limited areas, usuallyconstrained by testing costs. We validated a low-cost, rapid diagnosis test (RDT) for HCV in three different continents in 141individuals. The HCV RDT showed 100% specificity and sensitivity across different samples regardless of genotypeor viral load (in samples with such information, 90%). The HCV test validated in this study can allow for HCV screening in areas of need when properly used.Fil: Leathers, James S.. Vanderbilt University; Estados UnidosFil: Pisano, MarĂa BelĂ©n. Universidad Nacional de Cordoba. Facultad de Medicina. Instituto de VirologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: RĂ©, Viviana Elizabeth. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Cordoba. Facultad de Medicina. Instituto de VirologĂa; ArgentinaFil: van Oord, Gertine. Erasmus Medical Center; PaĂses BajosFil: Sultan, Amir. Addis Ababa University; EtiopĂaFil: Boonstra, Andre. Erasmus Medical Center; PaĂses BajosFil: Debes, Jose D.. Universidad de Minnesota; Estados Unido
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