Seasonal price patterns of selected agricultural commodities

Production and market planning has become increasingly crucial to successful farm management as per-unit profit margins have declined. Consequently, the indicators of the prices a farmer can expect to receive have grown in importance, too.https://lib.dr.iastate.edu/specialreports/1056/thumbnail.jp

SARA LEE FOODS TAKES FLIGHT: AN ECONOMIC IMPACT ANALYSIS OF A TURKEY PLANT CLOSURE

In 1998, the Sara Lee Corporation implemented a corporate strategy of deverticalization. Bil Mar Foods, Inc., a subsidiary of Sara Lee responsible for the processing of packaged meat products, followed the strategy by shutting down its turkey slaughter facility in Zeeland, Michigan. As a consequence, turkey growers in Michigan were left with no viable outlet for live bird slaughter and the potential end of live bird production in the region. This study analyzes the economic impact associated with the cessation of live bird slaughter at the Bil Mar Foods plant. The economic consequences may be as high as an $81 million loss in total industry output, a$29 million loss in income, and a total employment loss of nearly 800 jobs. Faced with these economic consequences, turkey growers in the region joined forces to form a valued-added cooperative.impact analysis, plant closure, turkey industry, Community/Rural/Urban Development, Livestock Production/Industries,

Nitrate pollution from horticultural production systems : tools for policy and advice from field to catchment scales

The implementation of the Nitrates Directive has imposed a requirement to restrict N fertiliser and manuring practices on farms across the EU in order to reduce nitrate losses to water. These requirements have since been extended by the more demanding Water Framework Directive, which broadens the focus from the control of farm practices to a consideration of the impacts of pollutants from all sources on water quality at a catchment or larger scale. Together, these Directives set limits for water quality, and identify general strategies for how these might be achieved. However, it is the responsibility of policy makers in each Nation State to design the details of the management practices and environmental protection measures required to meet the objectives of the legislation, to ensure they are appropriate for their specific types of land use and climate. This paper describes various modelling tools for comparing different cropping and land use strategies, and illustrates with examples how they can inform policy makers about the environmental benefits of changing management practices and how to prioritise them. The results can help to provide the specific advice on N fertiliser and land use management required by farmers and growers at a field scale, and by environmental managers at a catchment or larger scale. A further example of how results from multiple catchments can be up-scaled and compared using Geographic Information Systems is also outlined

Entry pathways of herpes simplex virus type 1 into human keratinocytes are dynamin- and cholesterol-dependent

Herpes simplex virus type 1 (HSV-1) can enter cells via endocytic pathways or direct fusion at the plasma membrane depending on the cell line and receptor(s). Most studies into virus entry have used cultured fibroblasts but since keratinocytes represent the primary entry site for HSV-1 infection in its human host, we initiated studies to characterize the entry pathway of HSV-1 into human keratinocytes. Electron microscopy studies visualized free capsids in the cytoplasm and enveloped virus particles in vesicles suggesting viral uptake both by direct fusion at the plasma membrane and by endocytic vesicles. The ratio of the two entry modes differed in primary human keratinocytes and in the keratinocyte cell line HaCaT. Inhibitor studies further support a role for endocytosis during HSV-1 entry. Infection was inhibited by the cholesterol-sequestering drug methyl-beta-cyclodextrin, which demonstrates the requirement for host cholesterol during virus entry. Since the dynamin-specific inhibitor dynasore and overexpression of a dominant-negative dynamin mutant blocked infection, we conclude that the entry pathways into keratinocytes are dynamin-mediated. Electron microscopy studies confirmed that virus uptake is completely blocked when the GTPase activity of dynamin is inhibited. Ex vivo infection of murine epidermis that was treated with dynasore further supports the essential role of dynamin during entry into the epithelium. Thus, we conclude that HSV-1 can enter human keratinocytes by alternative entry pathways that require dynamin and host cholesterol

Maternal fluoxetine exposure alters cortical hemodynamic and calcium response of offspring to somatosensory stimuli

Epidemiological studies have found an increased incidence of neurodevelopmental disorders in populations prenatally exposed to selective serotonin reuptake inhibitors (SSRIs). Optical imaging provides a minimally invasive way to determine if perinatal SSRI exposure has long-term effects on cortical function. Herein we probed the functional neuroimaging effects of perinatal SSRI exposure in a fluoxetine (FLX)-exposed mouse model. While resting-state homotopic contralateral functional connectivity was unperturbed, the evoked cortical response to forepaw stimulation was altered in FLX mice. The stimulated cortex showed decreased activity for FLX versus controls, by both hemodynamic responses [oxyhemoglobin (Hb

Evaluation der potenziellen Regeneratschädigung bei der Kallusumformung nach Distraktionsosteogenese der Mandibula: Eine experimentelle Untersuchung am Tiermodell

Zusammenfassung: Ziel: Bei der Korrektur dreidimensionaler Deformitäten des Gesichtsskelettes mit der Distraktionsosteogenese werden Umformungsvorgänge des Regenerates einerseits als Bestandteil des Behandlungsplans, andererseits im Falle eines Verlustes der Kontrolle über den Distraktionsvektor vorgenommen. Die vorliegende Untersuchung hatte das Ziel, die Grenzen der Kallusmanipulation zu beurteilen. Dazu wurden die Auswirkungen komprimierender sowie dehnender Einflüsse am gleichen Regenerat untersucht. Material und Methode: Bei 15Beagle-Hunden wurde mit speziell angefertigten bidirektionalen Distraktoren eine lineare Distraktion von 10mm beidseits im Unterkieferwinkel vorgenommen. Der neu gebildete Kallus wurde in einem Schritt um 20° anguliert, was im vorliegenden Modell einer Verkürzung/Verlängerung von ca. 35% der Ausgangslänge des Regenerates gleichkommt. Die Position des Rotationszentrums erlaubte es, das Regenerat gleichzeitig zu komprimieren und zu dehnen. Die Auswirkungen dieser mechanischen Einflüsse auf die Ossifikation des Regenerates wurden nach 6 bzw. 13Wochen beurteilt und mit einer Kontrollgruppe, bei der lediglich eine lineare Distraktion durchgeführt worden war, verglichen. Ergebnisse: Die radiologischen und histologischen Untersuchungen ergaben keinen statisch signifikanten Unterschied zwischen dem komprimierten und gedehnten Regenerat. Es zeigten sich jedoch im gedehnten Sektor des Kallus Zonen unvollständiger Ossifikation nach 6-wöchiger Konsolidierungszeit. Unter stabilen Verhältnissen wurde die verzögerte Knochenheilung im weiteren Verlauf kompensiert und eine vollständige Ossifikation nach 13Wochen erreicht. Schlussfolgerung: Unter stabilen Verhältnissen kann ein durch Distraktion gebildetes frisches Regenerat in einem beträchtlichen Ausmaß umgeformt werden, ohne die knöcherne Heilung bleibend zu kompromittieren. Die Dehnung des Kallus kann jedoch zu einer Verzögerung oder dem Ausbleiben des Ossifikationsprozesses führen und sollte vermieden werden. Dies lässt sich durch eine Überkorrektur der Regeneratlänge oder durch eine graduelle Angulation während des Distraktionsvorgangs erreiche

Exact Performance of Concatenated Quantum Codes

When a logical qubit is protected using a quantum error-correcting code, the net effect of coding, decoherence (a physical channel acting on qubits in the codeword) and recovery can be represented exactly by an effective channel acting directly on the logical qubit. In this paper we describe a procedure for deriving the map between physical and effective channels that results from a given coding and recovery procedure. We show that the map for a concatenation of codes is given by the composition of the maps for the constituent codes. This perspective leads to an efficient means for calculating the exact performance of quantum codes with arbitrary levels of concatenation. We present explicit results for single-bit Pauli channels. For certain codes under the symmetric depolarizing channel, we use the coding maps to compute exact threshold error probabilities for achievability of perfect fidelity in the infinite concatenation limit.Comment: An expanded presentation of the analytic methods and results from quant-ph/0111003; 13 pages, 6 figure