6,786 research outputs found

    Energy efficient continuous flow ash lockhopper

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    The invention relates to an energy efficient continuous flow ash lockhopper, or other lockhopper for reactor product or byproduct. The invention includes an ash hopper at the outlet of a high temperature, high pressure reactor vessel containing heated high pressure gas, a fluidics control chamber having an input port connected to the ash hopper's output port and an output port connected to the input port of a pressure letdown means, and a control fluid supply for regulating the pressure in the control chamber to be equal to or greater than the internal gas pressure of the reactor vessel, whereby the reactor gas is contained while ash is permitted to continuously flow from the ash hopper's output port, impelled by gravity. The main novelty resides in the use of a control chamber to so control pressure under the lockhopper that gases will not exit from the reactor vessel, and to also regulate the ash flow rate. There is also novelty in the design of the ash lockhopper shown in two figures. The novelty there is the use of annular passages of progressively greater diameter, and rotating the center parts on a shaft, with the center part of each slightly offset from adjacent ones to better assure ash flow through the opening

    Vpr Mediates Immune Evasion and HIV-1 Spread.

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    The molecular mechanisms by which human immunodeficiency virus (HIV-1) evades immunity to cause persistent infection remain incompletely characterized. Viral protein R (Vpr) is conserved in all primate lentiviruses, including HIV-1. Previous studies have demonstrated that Vpr is required for maximal infection of T lymphocytes in vivo. However, Vpr does not enhance HIV-1 infection of T lymphocytes under standard in vitro infection conditions, and the mechanism of Vpr function is poorly understood. Our work demonstrates that Vpr prevents the induction of a type I interferon-stimulated antiviral response in macrophages that targets Env and Env-containing virions for lysosomal degradation. By preventing this response, Vpr promotes Env-dependent virological synapse formation and enables efficient spread of HIV-1 from macrophages to activated T lymphocytes. This mode of spread requires direct cell-to-cell contact and is highly resistant to neutralizing antibodies. These studies provide a mechanistic explanation for the evolutionary conservation and function of Vpr.PHDMicrobiology and ImmunologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113293/1/davrcol_1.pd

    State Trends in Premiums and Deductibles, 2003-2010: The Need for Action to Address Rising Costs

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    Examines the rise in employer-based insurance premiums and deductibles and as a percentage of median household income. Projects average family coverage premiums in 2020 if federal health reform is not implemented and historical rates of increase continue

    Probing the qudit depolarizing channel

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    For the quantum depolarizing channel with any finite dimension, we compare three schemes for channel identification: unentangled probes, probes maximally entangled with an external ancilla, and maximally entangled probe pairs. This comparison includes cases where the ancilla is itself depolarizing and where the probe is circulated back through the channel before measurement. Compared on the basis of (quantum Fisher) information gained per channel use, we find broadly that entanglement with an ancilla dominates the other two schemes, but only if entanglement is cheap relative to the cost per channel use and only if the external ancilla is well shielded from depolarization. We arrive at these results by a relatively simple analytical means. A separate, more complicated analysis for partially entangled probes shows for the qudit depolarizing channel that any amount of probe entanglement is advantageous and that the greatest advantage comes with maximal entanglement

    Superconducting resonators as beam splitters for linear-optics quantum computation

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    A functioning quantum computer will be a machine that builds up, in a programmable way, nonclassical correlations in a multipartite quantum system. Linear optics quantum computation (LOQC) is an approach for achieving this function that requires only simple, reliable linear optical elements, namely beam splitters and phase shifters. Nonlinear optics is only required in the form of single-photon sources for state initialization, and detectors. However, the latter remain difficult to achieve with high fidelity. A new setting for quantum optics has arisen in circuit quantum electrodynamics (cQED) using superconducting (SC) quantum devices, and opening up the way to LOQC using microwave, rather than visible photons. Much progress is being made in SC qubits and cQED: high-fidelity Fock state generation and qubit measurements provide single photon sources and detection. Here we show that the LOQC toolkit in cQED can be completed with high-fidelity (>99.92%) linear optical elements.Comment: 4 pages, 3 figure

    Discrimination of unitary transformations in the Deutsch-Jozsa algorithm

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    We describe a general framework for regarding oracle-assisted quantum algorithms as tools for discriminating between unitary transformations. We apply this to the Deutsch-Jozsa problem and derive all possible quantum algorithms which solve the problem with certainty using oracle unitaries in a particular form. We also use this to show that any quantum algorithm that solves the Deutsch-Jozsa problem starting with a quantum system in a particular class of initial, thermal equilibrium-based states of the type encountered in solution state NMR can only succeed with greater probability than a classical algorithm when the problem size exceeds n105.n \sim 10^5.Comment: 7 pages, 1 figur

    Statistical comparison of ensemble implementations of Grover's search algorithm to classical sequential searches

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    We compare pseudopure state ensemble implementations, quantified by their initial polarization and ensemble size, of Grover's search algorithm to probabilistic classical sequential search algorithms in terms of their success and failure probabilities. We propose a criterion for quantifying the resources used by the ensemble implementation via the aggregate number of oracle invocations across the entire ensemble and use this as a basis for comparison with classical search algorithms. We determine bounds for a critical polarization such that the ensemble algorithm succeeds with a greater probability than the probabilistic classical sequential search. Our results indicate that the critical polarization scales as N^(-1/4) where N is the database size and that for typical room temperature solution state NMR, the polarization is such that the ensemble implementation of Grover's algorithm would be advantageous for N > 10^2
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