18,511 research outputs found
THE ECONOMIC IMPACTS OF A FOOT-AND-MOUTH DISEASE OUTBREAK: A REGIONAL ANALYSIS
Contagious animal diseases like foot-and-mouth disease (FMD) are often referred to as economic diseases because of the magnitude of economic harm they can cause to producers and to local communities. This study demonstrates the local economic impact of a hypothetical FMD outbreak in southwest Kansas, an area with high density of cattle feeding. The expected (most probable) economic impact of the disease hinges heavily on where the incidence of the disease occurs. If the disease were to occur in a cow-calf herd in the region economic impact is expected to be relatively small compared to if it were introduced simultaneously in five large feedlots in southwest Kansas. Disease surveillance, management strategies, mitigation investment, and overall diligence clearly need to be much greater in concentrated cattle feeding and processing areas at the large feeding operations in the region.Livestock Production/Industries,
Micromechanics of fatigue in woven and stitched composites
The goal is to determine how microstructural factors, especially the architecture of microstructural factors, control fatigue damage in 3D reinforced polymer composites. Test materials were fabricated from various preforms, including stitched quasi-isotropic laminates, and through-the-thickness angle interlock, layer-to-layer angle interlock, and through-the-thickness stitching effect weaves. Preforms were impregnated with a tough resin by a special vacuum infiltration method. Most tests are being performed in uniaxial compression/compression loading. In all cases to date, failure has occurred not by delamination, but by shear failure, which occurs suddenly rather than by gradual macroscopic crack growth. Some theoretical aspects of bridging are also examined
Evidence for magnetic clusters in NiV close to the quantum critical concentration
The d-metal alloy NiV undergoes a quantum phase transition from
a ferromagnetic ground state to a paramagnetic ground state as the vanadium
concentration is increased. We present magnetization, ac-susceptibility and
muon-spin relaxation data at several vanadium concentrations near the critical
concentration at which the onset of ferromagnetic order is
suppressed to zero temperature. Below , the muon data reveal a broad
magnetic field distribution indicative of long-range ordered ferromagnetic
state with spatial disorder. We show evidence of magnetic clusters in the
ferromagnetic phase and close to the phase boundary in this disordered
itinerant system as an important generic ingredient of a disordered quantum
phase transition. In contrast, the temperature dependence of the magnetic
susceptibility above is best described in terms of a magnetic quantum
Griffiths phase with a power-law distribution of fluctuation rates of dynamic
magnetic clusters. At the lowest temperatures, the onset of a short-range
ordered cluster-glass phase is recognized by an increase in the muon
depolarization in transverse fields and maxima in ac-susceptibility.Comment: 6 pages, 5 figures, submitted to Proceedings of SCES 201
Quasi-monoenergetic femtosecond photon sources from Thomson Scattering using laser plasma accelerators and plasma channels
Narrow bandwidth, high energy photon sources can be generated by Thomson
scattering of laser light from energetic electrons, and detailed control of the
interaction is needed to produce high quality sources. We present analytic
calculations of the energy-angular spectra and photon yield that parametrize
the influences of the electron and laser beam parameters to allow source
design. These calculations, combined with numerical simulations, are applied to
evaluate sources using conventional scattering in vacuum and methods for
improving the source via laser waveguides or plasma channels. We show that the
photon flux can be greatly increased by using a plasma channel to guide the
laser during the interaction. Conversely, we show that to produce a given
number of photons, the required laser energy can be reduced by an order of
magnitude through the use of a plasma channel. In addition, we show that a
plasma can be used as a compact beam dump, in which the electron beam is
decelerated in a short distance, thereby greatly reducing radiation shielding.
Realistic experimental errors such as transverse jitter are quantitatively
shown to be tolerable. Examples of designs for sources capable of performing
nuclear resonance fluorescence and photofission are provided
Color television study Final report, Nov. 1965 - Mar. 1966
Color television camera for transmission from lunar and earth orbits and lunar surfac
Using EuGeneCiD and EuGeneCiM computational tools for synthetic biology
Synthetic biology often relies on the design of genetic circuits, utilizing ‘‘bio parts’’ (modular DNA pieces) to accomplish desired responses to external stimuli. While such designs are usually intuited, detailed here is a computational approach to synthetic biology design and modeling using optimization-based tools named Eukaryotic Genetic Circuit Design and Modeling. These allow for designing and subsequent screening of genetic circuits to increase the chances of in vivo success and contribute to the development of an application development pipeline. For complete details on the use and execution of this protocol, please refer to Schroeder, Baber, and Saha (2021)
Topoisomerase activity assays in Neurospora
DNA topoisomerases are enzymes capable of altering the topological conformation of DNA by inducing transient single (Topoisomerase I) and double strand (Topoisomerase II) breaks
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