29,215 research outputs found

    Numerical evidence of the axial magnetic effect

    Get PDF
    The axial magnetic field, which couples to left- and right-handed fermions with opposite signs, may generate an equilibrium dissipationless energy flow of fermions in the direction of the field even in the presence of interactions. We report on numerical observation of this axial magnetic effect in quenched SU(2) lattice gauge theory. We find that in the deconfinement (plasma) phase the energy flow grows linearly with the increase of the strength of the axial magnetic field. In the confinement (hadron) phase the axial magnetic effect is absent. Our study indirectly confirms the existence of the chiral vortical effect since both these effects have the same physical origin related to the presence of the gravitational anomaly

    Enforcing Termination of Interprocedural Analysis

    Full text link
    Interprocedural analysis by means of partial tabulation of summary functions may not terminate when the same procedure is analyzed for infinitely many abstract calling contexts or when the abstract domain has infinite strictly ascending chains. As a remedy, we present a novel local solver for general abstract equation systems, be they monotonic or not, and prove that this solver fails to terminate only when infinitely many variables are encountered. We clarify in which sense the computed results are sound. Moreover, we show that interprocedural analysis performed by this novel local solver, is guaranteed to terminate for all non-recursive programs --- irrespective of whether the complete lattice is infinite or has infinite strictly ascending or descending chains

    Heavy-meson physics and flavour violation with a single generation

    Full text link
    We study flavour-violating processes which involve heavy B- and D-mesons and are mediated by Kaluza-Klein modes of gauge bosons in a previously suggested model where three generations of the Standard Model fermions originate from a single generation in six dimensions. We find the bound on the size R of the extra spatial dimensions 1/R>3.3 TeV, which arises from the three-body decay B_s to K mu e. Due to the still too low statistics this bound is much less stringent than the constraint arising from K to mu e, 1/R>64 TeV, which was found in a previous work (Frere et al., JHEP, 2003). Nevertheless, we argue that a clear signature of the model would be an observation of K to mu e and B_s to K mu e decays without observations of other flavour and lepton number changing processes at the same precision level.Comment: 15 page

    Real rank boundaries and loci of forms

    Full text link
    In this article we study forbidden loci and typical ranks of forms with respect to the embeddings of P1×P1\mathbb P^1\times \mathbb P^1 given by the line bundles (2,2d)(2,2d). We introduce the Ranestad-Schreyer locus corresponding to supports of non-reduced apolar schemes. We show that, in those cases, this is contained in the forbidden locus. Furthermore, for these embeddings, we give a component of the real rank boundary, the hypersurface dividing the minimal typical rank from higher ones. These results generalize to a class of embeddings of Pn×P1\mathbb P^n\times \mathbb P^1. Finally, in connection with real rank boundaries, we give a new interpretation of the 2×n×n2\times n \times n hyperdeterminant.Comment: 17 p

    Ultra-micro indentation characterisation of mouthguard materials

    Get PDF
    Abstract no. 109published_or_final_versio

    Non-invasive detection of animal nerve impulses with an atomic magnetometer operating near quantum limited sensitivity

    Get PDF
    Magnetic fields generated by human and animal organs, such as the heart, brain and nervous system carry information useful for biological and medical purposes. These magnetic fields are most commonly detected using cryogenically-cooled superconducting magnetometers. Here we present the frst detection of action potentials from an animal nerve using an optical atomic magnetometer. Using an optimal design we are able to achieve the sensitivity dominated by the quantum shot noise of light and quantum projection noise of atomic spins. Such sensitivity allows us to measure the nerve impulse with a miniature room-temperature sensor which is a critical advantage for biomedical applications. Positioning the sensor at a distance of a few millimeters from the nerve, corresponding to the distance between the skin and nerves in biological studies, we detect the magnetic field generated by an action potential of a frog sciatic nerve. From the magnetic field measurements we determine the activity of the nerve and the temporal shape of the nerve impulse. This work opens new ways towards implementing optical magnetometers as practical devices for medical diagnostics.Comment: Main text with figures, and methods and supplementary informatio

    Coherent quantum phase slip

    Full text link
    A hundred years after discovery of superconductivity, one fundamental prediction of the theory, the coherent quantum phase slip (CQPS), has not been observed. CQPS is a phenomenon exactly dual to the Josephson effect: whilst the latter is a coherent transfer of charges between superconducting contacts, the former is a coherent transfer of vortices or fluxes across a superconducting wire. In contrast to previously reported observations of incoherent phase slip, the CQPS has been only a subject of theoretical study. Its experimental demonstration is made difficult by quasiparticle dissipation due to gapless excitations in nanowires or in vortex cores. This difficulty might be overcome by using certain strongly disordered superconductors in the vicinity of the superconductor-insulator transition (SIT). Here we report the first direct observation of the CQPS in a strongly disordered indium-oxide (InOx) superconducting wire inserted in a loop, which is manifested by the superposition of the quantum states with different number of fluxes. Similarly to the Josephson effect, our observation is expected to lead to novel applications in superconducting electronics and quantum metrology.Comment: 14 pages, 3 figure

    ANTI-INFLAMMATORY AND ANTIBACTERIAL ACTIVITY OF JATROPHA CURCAS LINN.

    Get PDF
    Jatropha curcas Linn., a Bio-diesel plant known for various medicinal uses in folklore has been evaluated for few pharmacological aspects. The plant is being collected, dried and extracted by maceration method with ethanol and water. They were concentrated using vacuum distillation and the extracts were used for the evaluation of anti-inflammatory, analgesic and antibacterial activity using Formalin induced paw edema method, eddy’s hot plate method and disc diffusion method respectively. The analgesic and anti-inflammatory activity of bark water extract and leaf water extract was found significant at P<0.05 and P<0.001 respectively. The maximum analgesic effect was observed at 60min at 300mg/kg (i.p) and was similar to that of standard aspirin (50mg/kg). The edema inhibition effect was 100% for leaf water extract (300mg/kg) after 24hrs and was found effective when compared with standard Ibuprofen (50mg/kg). The antibacterial activity was also found effective at 10mg/ml

    A conserved filamentous assembly underlies the structure of the meiotic chromosome axis.

    Get PDF
    The meiotic chromosome axis plays key roles in meiotic chromosome organization and recombination, yet the underlying protein components of this structure are highly diverged. Here, we show that 'axis core proteins' from budding yeast (Red1), mammals (SYCP2/SYCP3), and plants (ASY3/ASY4) are evolutionarily related and play equivalent roles in chromosome axis assembly. We first identify 'closure motifs' in each complex that recruit meiotic HORMADs, the master regulators of meiotic recombination. We next find that axis core proteins form homotetrameric (Red1) or heterotetrameric (SYCP2:SYCP3 and ASY3:ASY4) coiled-coil assemblies that further oligomerize into micron-length filaments. Thus, the meiotic chromosome axis core in fungi, mammals, and plants shares a common molecular architecture, and likely also plays conserved roles in meiotic chromosome axis assembly and recombination control

    Inverse Classification for Comparison-based Interpretability in Machine Learning

    Full text link
    In the context of post-hoc interpretability, this paper addresses the task of explaining the prediction of a classifier, considering the case where no information is available, neither on the classifier itself, nor on the processed data (neither the training nor the test data). It proposes an instance-based approach whose principle consists in determining the minimal changes needed to alter a prediction: given a data point whose classification must be explained, the proposed method consists in identifying a close neighbour classified differently, where the closeness definition integrates a sparsity constraint. This principle is implemented using observation generation in the Growing Spheres algorithm. Experimental results on two datasets illustrate the relevance of the proposed approach that can be used to gain knowledge about the classifier.Comment: preprin
    corecore