9,057 research outputs found

    Supersymmetry on Jacobstahl lattices

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    It is shown that the construction of Yang and Fendley (2004 {\it J. Phys. A: Math.Gen. {\bf 37}} 8937) to obtainsupersymmetric systems, leads not to the open XXZ chain with anisotropy Δ=1/2\Delta =-{1/2} but to systems having dimensions given by Jacobstahl sequences.For each system the ground state is unique. The continuum limit of the spectra of the Jacobstahl systems coincide, up to degeneracies, with that of the Uq(sl(2))U_q(sl(2)) invariant XXZ chain for q=exp(iπ/3)q=\exp(i\pi/3). The relation between the Jacobstahl systems and the open XXZ chain is explained.Comment: 6 pages, 0 figure

    Non-Invasive Ventilation Sensor Mask (NIVSM): Preliminary Design and Testing

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    Previous research has emphasized the significance of mask and interface design in non-invasive ventilation (NIV) and the prevention of pressure ulcers (PUs). Multiple variables are involved in the necrosis process, but the skin-mask interface has the significant impact. A preliminary design of a custom-fit Mask (CFM) embedded with microclimate sensor has been introduced previously. This study aims to improve the comfort and safety of patients that use NIV masks for long periods. The personalized cushion fit (PCF) is designed using 3D scanning and printing technology and integrated into a pre existing mask. Integration with a preexisting mask has been achieved by fabricating a modular design that acts as a disposable PCF. Embedded sensors are added to the mask to measure the skin-mask microclimate. Real-time data is plotted and monitored for critical conditions and to identify other key features. A preliminary temperaturehumidity (T-H) monitoring of the skin-mask interface for both PCF and pre-existing mask shows fluctuation trends that could potentially induce PUs. However, there is a more sensitive reaction in the PCF test

    A Consumer Test of Canned Seasoned Salad Tomatoes

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    Consumer, Canned Tomatoes, Salad Tomatoes, Seasoned Tomatoes, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

    TGCat, The Chandra Transmission Grating Catalog and Archive: Systems, Desgin and Accessibility

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    The recently released Chandra Transmission Grating Catalog and Archive, TGCat, presents a fully dynamic on-line catalog allowing users to browse and categorize Chandra gratings observations quickly and easily, generate custom plots of resulting response corrected spectra on-line without the need for special software and to download analysis ready products from multiple observations in one convenient operation. TGCat has been registered as a VO resource with the NVO providing direct access to the catalogs interface. The catalog is supported by a back-end designed to automatically fetch newly public data, process, archive and catalog them, At the same time utilizing an advanced queue system integrated into the archive's MySQL database allowing large processing projects to take advantage of an unlimited number of CPUs across a network for rapid completion. A unique feature of the catalog is that all of the high level functions used to retrieve inputs from the Chandra archive and to generate the final data products are available to the user in an ISIS written library with detailed documentation. Here we present a structural overview of the Systems, Design, and Accessibility features of the catalog and archive.United States. National Aeronautics and Space Administration (Chandra X-ray Center (CXC) NASA contract NAS8-03060)United States. National Aeronautics and Space Administration (Smithsonian Astrophysical Observatory (SAO) contract SV3-73016 for the Chandra X-Ray Center and Science Instruments

    Probing Wolf-Rayet Winds: Chandra/HETG X-Ray Spectra of WR 6

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    With a deep Chandra/HETGS exposure of WR 6, we have resolved emission lines whose profiles show that the X-rays originate from a uniformly expanding spherical wind of high X-ray-continuum optical depth. The presence of strong helium-like forbidden lines places the source of X-ray emission at tens to hundreds of stellar radii from the photosphere. Variability was present in X-rays and simultaneous optical photometry, but neither were correlated with the known period of the system or with each other. An enhanced abundance of sodium revealed nuclear processed material, a quantity related to the evolutionary state of the star. The characterization of the extent and nature of the hot plasma in WR 6 will help to pave the way to a more fundamental theoretical understanding of the winds and evolution of massive stars.Comment: Accepted by the Astrophysical Journa

    A deformed analogue of Onsager's symmetry in the XXZ open spin chain

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    The XXZ open spin chain with general integrable boundary conditions is shown to possess a q-deformed analogue of the Onsager's algebra as fundamental non-abelian symmetry which ensures the integrability of the model. This symmetry implies the existence of a finite set of independent mutually commuting nonlocal operators which form an abelian subalgebra. The transfer matrix and local conserved quantities, for instance the Hamiltonian, are expressed in terms of these nonlocal operators. It follows that Onsager's original approach of the planar Ising model can be extended to the XXZ open spin chain.Comment: 12 pages; LaTeX file with amssymb; v2: typos corrected, clarifications in the text; v3: minor changes in references, version to appear in JSTA

    Reversing microcrystalline tests: an analytical approach to recycling of microcrystals from drugs of abuse

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    A combined analysis of microcrystalline tests followed by LC-MS or GC-MS analysis is described. Microcrystalline tests are shown to be non-destructive as addition products formed were easily dissociated after the application of an appropriate solvent. Subsequent analysis of the sample was done to quantify the recovery of the drug. Examples were performed using the date rape drug γ-hydroxybutyrate (GHB) and the synthetic opioid methadone
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