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Animal disease outbreaks can cause disruptions in domestic and international markets. Business continuity aims to provide a proactive approach to alleviate some of these negative effects on consumers, producers, and agribusinesses. Using a partial equilibrium model of the U.S. egg industry, the economic impacts of business continuity during an epidemiological simulated disease event are modeled. Results show total welfare losses can be reduced by allowing permitted movement during an outbreak given a specified level of biosecurity. Understanding the potential market responses business continuity can have on the market may lead to reductions in the negative implications of a disease event.
We study thermodynamic formalism for the family of robustly transitive diffeomorphisms introduced by Mañé, establishing existence and uniqueness of equilibrium states for natural classes of potential functions. In particular, we characterize the Sinaĭ–Ruelle–Bowen measures for these diffeomorphisms as unique equilibrium states for a suitable geometric potential. We also obtain large deviations and multifractal results for the unique equilibrium states produced by the main theorem.
The field of Oriental studies was the main context in which amateur and professional scholars developed the academic study of Islam before World War II. The role of religion in the rise of this discipline is now widely acknowledged, but the role of religion, particularly Christianity, in the critique and transformation of Orientalism after World War II has never been explored. Given the prevalence of Christian scholars in Islamic studies after 1945, why has this been the case?
Pessoa's (2013) integrative model of emotion and cognition can be strengthened in two ways: first, by clarification and refinement of key concepts and terminology, and second by the incorporation of an additional key neural system into the model, the locus coeruleus/norepinephrine system.
The nearby starburst galaxies M82 and NGC 253 are now detected in GeV and TeV γ-rays, allowing us to directly study cosmic rays (CRs) in starburst galaxies. Combined with radio observations, the detections constrain the propagation and density of CRs in these starbursts. We discuss the implications for “proton calorimetry”, whether CR protons cool through pion losses before escaping these galaxies. The ratio of γ-ray and radio luminosities constrains how much of the CR electron cooling is due to synchrotron losses. As for leptonic emission, we predict that synchrotron and Inverse Compton emission make up ~1–10% of the unresolved hard X-ray emission from M82, and a few percent or less of the total X-ray emission from starbursts. A detection of these components would inform us of the magnetic field strength and 10 – 100 TeV electron spectrum. We conclude by discussing the prospects for detecting leptonic MeV γ-rays from starbursts and the cosmic γ-ray background.
A transmission electron microscopy study has revealed that the banded microstructure produced in Cu-61.7 at. pct. Ag after surface laser melting and resolidification is not due to a cellular breakdown of the interface as previously thought, but consists of alternating regions of the extended metastable solid solution, y, and a coupled growth structure containing thin plates of y and the copper-rich phase β'. The spacing of this coupled growth structure is approximately 100 Å, which is less than half the minimum spacing yet observed for coupled growth from the melt in Ag-Cu.
In order to explain the banded microstructure a theoretical model has been developed based on a finite elements solution of the diffusion equation in the melt, the interface response functions for continuous growth derived by Aziz and Kaplan and a recently developed theory for coupled growth that includes far-from-equilibrium regimes by Yankov et al..
High Power asymmetric SiC GTOs (Gate Turn-Off Thyristors) were fabricated on n-type 4H-SiC substrates with multiple epi-layers and were tested to investigate breakdown voltage, maximum current density, switching characteristics, and temperature dependences.
Comparison of breakdown voltages achieved by GTOs with Guard Ring edge termination and GTOs with a proprietary Junction Termination Extension (JTE) fabricated on the same wafer are made. Individual GTOs with a nominal area of 4 mm2 (2 mm × 2 mm) utilizing the JTE were tested in forward bias and found to support over 6 kV at leakage currents of less than 5 μA. In addition, GTOs with a nominal area of 0.25 mm2 (0.5 mm × 0.5 mm) utilizing the JTE were found to support over 7 kV. These blocking voltages are the highest reported for GTOs in SiC. [1–5] Wafer maps of the breakdown voltages for older and newer wafers suggest an improvement of the material. The defect density for the newer wafer is estimated to be greater than the micropipe density.
The on-state characteristics are equally impressive, with 4 mm2 GTOs carrying > 1000 A/cm2. The GTO has a forward voltage drop of 3.66 V at a current density of 300 A/cm2 at room temperature and a forward voltage drop of 3.1 V at 300 A/cm2 at 224 °C. This indicates that on-state losses should not be excessive, even at high current densities and high temperatures.
In attempts to provide an active solution for the rigidization of flexible space structures, internal resistive heating is applied to a novel thermosetting resin. Carbon-fiber tow coated in U-Nyte Set 201A, which cures at ∼150°C, was heated by passing electric current through the reinforcing material. Using a proportional-integral (PI) controller, precise temperature control of the heating process was established. Samples cured via controlled internal resistive heating were heated to 160°C and underwent material consolidation in less than 7 minutes. A change in material stiffness was measured to be almost two orders of magnitude greater than that of an uncured material.
Measurements on URu2-xRexSi2 single crystals indicate that substitution of Re for Ru in URu2Si2 reduces the transition temperature of the hidden order state and quickly destroys superconductivity. At intermediate Re concentrations, weak ferromagnetism emerges and non Fermi liquid (NFL) behavior is observed in the low-temperature specific heat and electrical resistivity. A scaled Arrott analysis of the magnetization indicates the onset of ferromagnetism at x =0.15, where the hidden order disappears, and that the quantum phase transition is associated with novel critical exponents.
Until now, availability of wood from the Younger Dryas abrupt cooling event (YDE) in N. America ca. 12.9 to 11.6 ka has been insufficient to develop high-resolution chronologies for refining our understanding of YDE conditions. Here we present a multi-proxy tree-ring chronology (ring widths, “events” evidenced by microanatomy and macro features, stable isotopes) from a buried black spruce forest in the Great Lakes area (Liverpool East site), spanning 116 yr at ca. 12,000 cal yr BP. During this largely cold and wet period, the proxies convey a coherent and precise forest history including frost events, tilting, drowning and burial in estuarine sands as the Laurentide Ice Sheet deteriorated. In the middle of the period, a short mild interval appears to have launched the final and largest episode of tree recruitment. Ultimately the tops of the trees were sheared off after death, perhaps by wind-driven ice floes, culminating an interval of rising water and sediment deposition around the base of the trees. Although relative influences of the continental ice sheet and local effects from ancestral Lake Michigan are indeterminate, the tree-ring proxies provide important insight into environment and ecology of a N. American YDE boreal forest stand.
We reconstructed Holocene water-level and vegetation dynamics based on pollen and plant macrofossils from a coastal lake in Upper Michigan. Our primary objective was to test the hypothesis that major fluctuations in Great Lakes water levels resulted in part from climatic changes. We also used our data to provide temporal constraints to the mid-Holocene dry period in Upper Michigan. From 9600 to 8600 cal yr B.P. a shallow, lacustrine environment characterized the Mud Lake basin. A Sphagnum-dominated wetland occupied the basin during the mid-Holocene dry period (∼8600 to 6600 cal yr B.P.). The basin flooded at 6600 cal yr B.P. as a result of rising water levels associated with the onset of the Nipissing I phase of ancestral Lake Superior. This flooding event occurred contemporaneously with a well-documented regional expansion of Tsuga. Betula pollen increased during the Nipissing II phase (4500 cal yr B.P.). Macrofossil evidence from Mud Lake suggests that Betula alleghaniensis expansion was primarily responsible for the rising Betula pollen percentages. Major regional and local vegetational changes were associated with all the major Holocene highstands of the western Great Lakes (Nipissing I, Nipissing II, and Algoma). Traditional interpretations of Great Lakes water-level history should be revised to include a major role of climate.