683 research outputs found

    Method for Making a Heavy Wax Composition

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    The invention includes a process of making a wax composition including: a process for making a heavy wax composition including the steps of (1) contacting a waste plastics feed containing primarily polyethylene in a pyrolysis zone at sub-atmospheric pressure, whereby at least a portion of the waste plastics feed is cracked, thereby forming a pyrolysis zone effluent including 1-olefins and n-paraffins; and (2) passing the pyrolysis zone effluent to a hydrotreating zone, for contacting with a hydrotreating catalyst at catalytic conditions

    Shapes of the Proton

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    A model proton wave function, constructed using Poincare invariance, and constrained by recent electromagnetic form factor data, is used to study the shape of the proton. Spin-dependent quark densities are defined as matrix elements of density operators in proton states of definite spin-polarization, and shown to have an infinite variety of non-spherical shapes. For high momentum quarks with spin parallel to that of the proton, the shape resembles that of a peanut, but for quarks with anti-parallel spin the shape is that of a bagel.Comment: 8 pages, 5 figures, to be submitted to Phys. Rev. C This corrects a few typos and explains some further connections with experiment

    Elevated cerebral spinal fluid biomarkers in children with mucopolysaccharidosis I-H.

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    Mucopolysaccharidosis (MPS) type-IH is a lysosomal storage disease that results from mutations in the IDUA gene causing the accumulation of glycosaminoglycans (GAGs). Historically, children with the severe phenotype, MPS-IH (Hurler syndrome) develop progressive neurodegeneration with death in the first decade due to cardio-pulmonary complications. New data suggest that inflammation may play a role in MPS pathophysiology. To date there is almost no information on the pathophysiologic changes within the cerebral spinal fluid (CSF) of these patients. We evaluated the CSF of 25 consecutive patients with MPS-IH. While CSF glucose and total protein were within the normal range, we found a significantly mean elevated CSF opening pressure at 24 cm H2O (range 14-37 cm H2O). We observed a 3-fold elevation in CSF heparan sulfate and a 3-8 fold increase in MPS-IH specific non-reducing ends, I0S0 and I0S6. Cytokine analyses in CSF of children with MPS-IH showed significantly elevated inflammatory markers including: MCP-1 SDF-1a, IL-Ra, MIP-1b, IL-8, and VEGF in comparison to unaffected children. This is the largest report of CSF characteristics in children with MPS-IH. Identification of key biomarkers may provide further insight into the inflammatory-mediated mechanisms related to MPS diseases and perhaps lead to improved targeted therapies

    Methionine enkephalin: immunomodulator in normal volunteers, cancer and AIDS patients

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    Clinical studies of the immunological effects of methionine enkephalin in normal volunteers, cancer, and AIDS patients are summarized. The major immunology changes seen were increases in T cell subsets, natural killer activity, as well as mitogen blastogenesis. Clinically, the cancer and ARC patients did not develop infections

    Revealing Nuclear Pions Using Electron Scattering

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    A model for the pionic components of nuclear wave functions is obtained from light front dynamical calculations of binding energies and densities. The pionic effects are small enough to be consistent with measured nuclear di-muon production data and with the nucleon sea. But the pion effects are large enough to predict substantial nuclear enhancement of the cross section for longitudinally polarized virtual photons for the kinematics accessible at Jefferson Laboratory.Comment: 9 pages, 4 figure

    Restoration of rotational invariance of bound states on the light front

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    We study bound states in a model with scalar nucleons interacting via an exchanged scalar meson using the Hamiltonian formalism on the light front. In this approach manifest rotational invariance is broken when the Fock space is truncated. By considering an effective Hamiltonian that takes into account two meson exchanges, we find that this breaking of rotational invariance is decreased from that which occurs when only one meson exchange is included. The best improvement occurs when the states are weakly bound.Comment: 20 pages, 6 figures, uses feynMF; changed typos, clarified use of angular momentu

    QCD Rescattering and High Energy Two-Body Photodisintegration of the Deuteron

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    Photon absorption by a quark in one nucleon followed by its high momentum transfer interaction with a quark in the other may produce two final-state nucleons with high relative momentum. We sum the relevant quark rescattering diagrams, to show that the scattering amplitude depends on a convolution between the large angle pnpn scattering amplitude, the hard photon-quark interaction vertex and the low-momentum deuteron wave function. The computed absolute values of the cross section are in reasonable agreement with the data.Comment: 4 pages, revised version to be published in Phys. Rev. Let
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