The Economics of Testing for Biotech Grain: Application to StarLink Corn

StarLink corn, a biotech variety not approved for human food use, disrupted the marketing system in 2000 because of inadvertent commingling. Testing protocols have since been established for detection of StarLink in corn shipments to Japan. Domestic food manufacturers, anxious to avoid risks of contamination and product recalls, also test for StarLink kernels. This paper provides an overview of the economics of testing. What are the risks facing buyers and sellers, and how are these influenced by different testing protocols? How do market premiums and discounts, testing costs, and prior beliefs affect the incentives to test? A conceptual model is developed in which sellers can choose whether to pre-test grain prior to shipment. Simulation analysis is used to illustrate the impact of market premiums and other variables on testing incentives and buyer risk.Research and Development/Tech Change/Emerging Technologies,

The Economics of Testing for Biotech Grain: Application to StarLink Corn

StarLink corn, a variety not approved for human use, disrupted the marketing system in 2000 because of inadvertent commingling. This paper provides an overview of the economics of testing grain for biotech content. What are the risks facing buyers and sellers, and how are these influenced by testing protocols? How do market premiums and discounts, testing costs, and prior beliefs affect the incentives to test? A conceptual model is developed in which sellers choose whether to pre-test grain prior to shipment. Through simulation analysis, we illustrate the impact of market premiums and other variables on testing incentives and buyer risk.biotechnology, grain marketing, quality risk, StarLink, testing, Crop Production/Industries,

Economic Impact of Fusarium Head Blight in Malting Barley: Blending Margins and Firm-Level Risk

FHB and DON present significant challenges to producers, grain elevators, and the brewing industry. Yield reductions and price discounts incurred by producers in North Dakota, Minnesota, and South Dakota averaged about $45.3 million annually during the years 1998 through 2000. Losses are more substantial when secondary economic impacts are considered. For every$1 of scab losses incurred by the producer, $2 in losses are incurred in other areas of rural and state economies. One way of mitigating these losses is to blend barley with DON and barley without DON. Results from the grain blending model show a sharp decline of DON discounts and losses after blending. The average discount fell from$0.57/bu to $0.17/bu in 1998,$0.48/bu to $0.14/bu in 1999, and$0.38/bu to $0.15/bu in 2000. However, producers may not benefit from blending margins (gains from improved quality less blending costs) because these margins are the primary source of revenue for grain elevators. It should also be noted that the aggregate costs of DON to grain handlers are difficult to estimate because DON is subject to an unusual amount of measurement uncertainty, and penalties for excess DON pose an unusual level of risk.Crop Production/Industries,

IMPACTS OF DON IN THE MALTING BARLEY SUPPLY CHAIN: AGGREGATE COSTS AND FIRM-LEVEL RISKS

DON is a toxic byproduct of fusarium head blight (FHB), a fungal disease of small grains. Beginning in 1993, a prolonged outbreak of FHB occurred in the Upper Midwest, the traditional source of most six-rowed malting barley produced in the United States. Price discounts associated with DON in barley have been significant. This paper has two objectives. The first is to estimate the impact of DON on the value of malting barley grown in the Upper Midwest. Using crop quality data, we use a linear programming model to derive optimal blends of barley supplies, given discount schedules and the distribution of quality factors. The premise is that blending activities, on a regional scale, allow a larger fraction of the crop to be sold as malting. The second objective is to assess the risks associated with DON in the context of a firm-level blending model. We frame a nonlinear optimization problem in which an elevator seeks to maximize the expected sales value of the barley in its bins. Price discounts for several quality factors are incorporated in the analysis, along with probability distributions for DON. Treating DON as a random quality factor adds some interesting complexity to the standard grain blending problem. Attachments: <a href="/Data/ndsu/aem187a.xls">aem187a.xls</a> <a href="/Data/ndsu/aem187a.xls">aem187b.xls</a> <a href="/Data/ndsu/aem187a.xls">aem187c.xls</a> <a href="/Data/ndsu/aem187a.xls">aem187d.xls</a>barley, malt, DON, fusarium head blight, grain quality, blending, Production Economics,

North American Barley Trade and Competition

International Relations/Trade,

Constructing two-sided simultaneous confidence intervals for multinomial proportions for small counts in a large number of cells

Confidence intervals for multinomial proportions are often constructed using large-sample methods that rely on expected cell counts of 5 or greater. In situations that give rise to a large number of categories, the cell counts may not be of adequate size to ensure the appropriate overall coverage probability and alternative methods of construction have been proposed. Sison and Glaz (1995) developed a method of constructing two-sided confidence intervals for multinomial proportions that is based on the doubly truncated Poisson distribution and their method performs well when the cell counts are fairly equally dispersed over a large number of categories. In fact, the Sison and Glaz (1995) intervals appear to outperform other methods of simultaneous construction in terms of coverage probabilities and interval length in these situations. To make the method available to researchers, we have developed a SAS macro to construct the intervals proposed by Sison and Glaz (1995).

Coarse-grained description of localized inelastic deformation in amorphous metals

The sequence of shear transformation events that lead to a shear band transition in amorphous metals is described by a spatially random coarse-grained model calibrated to obey the thermodynamic scaling relations that govern flow in a real glass. The model demonstrates that shear banding is a consequence of local shear transformation events that self-organize along planes of maximum resolved shear stress to form extended bands of highly localized deformation. This description suggests that shear band formation is incipient during the early stages of deformation of a randomly inhomogeneous material

Fragility of iron-based glasses

The viscosity of various iron-based bulk-glass-forming liquids is measured around the glass transition, and the associated fragility is calculated. Fragility is found to vary broadly between compositions, from a low value of ~43, which indicates fairly “strong” liquid behavior, to ~65, well within the region of “fragile” behavior. Despite a strong covalent bonding identified in the structure of this class of metal/metalloid glasses, their liquid fragility can be remarkably high, exceeding even the very fragile palladium and platinum bulk-glass formers. An inverse correlation between glass-forming ability and fragility is identified, suggesting that iron-based glasses are effectively “kinetically” stabilized

Rheology and ultrasonic properties of Pt57.5Ni5.3Cu14.7P22.5 liquid

The equilibrium and nonequilibrium viscosity and isoconfigurational shear modulus of Pt57.5Ni5.3Cu14.7P22.5 supercooled liquid are evaluated using continuous–strain-rate compression experiments and ultrasonic measurements. By means of a thermodynamically-consistent cooperative shear model, variations in viscosity with both temperature and strain rate are uniquely correlated to the variations in isoconfigurational shear modulus, which leads to an accurate prediction of the liquid fragility and to a good description of the liquid strain-rate sensitivity

Eosinophilic bronchitis, eosinophilic granuloma, and eosinophilic bronchopneumopathy in 75 dogs (2006-2016).

BackgroundEosinophilic lung disease is a poorly understood inflammatory airway disease that results in substantial morbidity.ObjectiveTo describe clinical findings in dogs with eosinophilic lung disease defined on the basis of radiographic, bronchoscopic, and bronchoalveolar lavage fluid (BAL) analysis. Categories included eosinophilic bronchitis (EB), eosinophilic granuloma (EG), and eosinophilic bronchopneumopathy (EBP).AnimalsSeventy-five client owned dogs.MethodsMedical records were retrospectively reviewed for dogs with idiopathic BAL fluid eosinophilia. Information abstracted included duration and nature of clinical signs, bronchoscopic findings, and laboratory data. Thoracic radiographs were evaluated for the pattern of infiltrate, bronchiectasis, and lymphadenomegaly.ResultsThoracic radiographs were normal or demonstrated a bronchial pattern in 31 dogs assigned a diagnosis of EB. Nine dogs had intraluminal mass lesions and were bronchoscopically diagnosed with EG. The remaining 35 dogs were categorized as having EBP based on radiographic changes, yellow green mucus in the airways, mucosal changes, and airway collapse. Age and duration of cough did not differ among groups. Dogs with EB were less likely to have bronchiectasis or peripheral eosinophilia, had lower total nucleated cell count in BAL fluid, and lower percentage of eosinophils in BAL fluid compared to dogs in the other 2 groups. In contrast to previous reports, prolonged survival (&gt;55 months) was documented in dogs with EG.Conclusions and clinical importanceDogs with eosinophilic lung disease can be categorized based on imaging, bronchoscopic and BAL fluid cytologic findings. Further studies are needed to establish response to treatment in these groups