15,700 research outputs found

    Anomaly Inflow and Membrane Dynamics in the QCD Vacuum

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    Large NcN_c and holographic arguments, as well as Monte Carlo results, suggest that the topological structure of the QCD vacuum is dominated by codimension-one membranes which appear as thin dipole layers of topological charge. Such membranes arise naturally as D6D6 branes in the holographic formulation of QCD based on IIA string theory. The polarizability of these membranes leads to a vacuum energy θ2\propto \theta^2, providing the origin of nonzero topological susceptibility. Here we show that the axial U(1) anomaly can be formulated as anomaly inflow on the brane surfaces. A 4D gauge transformation at the brane surface separates into a 3D gauge transformation of components within the brane and the transformation of the transverse component. The in-brane gauge transformation induces currents of an effective Chern-Simons theory on the brane surface, while the transformation of the transverse component describes the transverse motion of the brane and is related to the Ramond-Ramond closed string field in the holographic formulation of QCD. The relation between the surface currents and the transverse motion of the brane is dictated by the descent equations of Yang-Mills theory.Comment: 22 pages, 3 figure

    What catches our eyes? : semiotic research on the advertisement of Budweiser

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    2010-2011 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    Destruction of Neel order and appearance of superconductivity in electron-doped cuprates by oxygen annealing process

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    We use thermodynamic and neutron scattering measurements to study the effect of oxygen annealing on the superconductivity and magnetism in Pr0.88_{0.88}LaCe0.12_{0.12}CuO4δ_{4-\delta}. Although the transition temperature TcT_c measured by susceptibility and superconducting coherence length increase smoothly with gradual oxygen removal from the annealing process, bulk superconductivity, marked by a specific heat anomaly at TcT_c and the presence of a neutron magnetic resonance, only appears abruptly when TcT_c is close to the largest value. These results suggest that the effect of oxygen annealing must be first determined in order to establish a Ce-doping dependence of antiferromagnetism and superconductivity phase diagram for electron-doped copper oxides.Comment: 5 pages, 4 figures, accepted by Phys. Rev.

    Antiviral treatment alters the frequency of activating and inhibitory receptor-expressing natural killer cells in chronic Hepatitis B virus infected patients

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    Natural killer (NK) cells play a critical role in innate antiviral immunity, but little is known about the impact of antiviral therapy on the frequency of NK cell subsets. To this aim, we performed this longitudinal study to examine the dynamic changes of the frequency of different subsets of NK cells in CHB patients after initiation of tenofovir or adefovir therapy. We found that NK cell numbers and subset distribution differ between CHB patients and normal subjects; furthermore, the association was found between ALT level and CD158b+ NK cell in HBV patients. In tenofovir group, the frequency of NK cells increased during the treatment accompanied by downregulated expression of NKG2A and KIR2DL3. In adefovir group, NK cell numbers did not differ during the treatment, but also accompanied by downregulated expression of NKG2A and KIR2DL3. Our results demonstrate that treatment with tenofovir leads to viral load reduction, and correlated with NK cell frequencies in peripheral blood of chronic hepatitis B virus infection. In addition, treatments with both tenofovir and adefovir in chronic HBV infected patients induce a decrease of the frequency of inhibitory receptor+ NK cells, which may account for the partial restoration of the function of NK cells in peripheral blood following treatment

    Nasal septal perforation repair with an inferior turbinate flap and acellular dermal matrix

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    Nasal septal perforation is an uncommon disorder that can cause disturbance of nasal physiology. The perforations can vary widely in size, location, and symptomatology. Many different closure techniques have been described in the literature; however, no gold standard has been recognized. The choice of surgical technique usually depends on the characteristics of the perforation and surgeon experience. Due to the goal of perforation repair being restoration of normal nasal physiology, techniques with the best outcomes have been those resurfacing the septum with nasal respiratory mucosa. Here we present our novel surgical method for large (\u3e 2 cm) septal perforation closure using a modification of the inferior turbinate flap repair using a polydioxanone plate and the acellular dermal matrix allograft (Alloderm, Allergan Inc.)

    Magnetism and the Weiss Exchange Field - A Theoretical Analysis Inspired by Recent Experiments

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    The huge spin precession frequency observed in recent experiments with spin-polarized beams of hot electrons shot through magnetized films is interpreted as being caused by Zeeman coupling of the electron spins to the so-called Weiss exchange field in the film. A "Stern-Gerlach experiment" for electrons moving through an inhomogeneous exchange field is proposed. The microscopic origin of exchange interactions and of large mean exchange fields, leading to different types of magnetic order, is elucidated. A microscopic derivation of the equations of motion of the Weiss exchange field is presented. Novel proofs of the existence of phase transitions in quantum XY-models and antiferromagnets, based on an analysis of the statistical distribution of the exchange field, are outlined.Comment: 36 pages, 3 figure
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