Topologically-Protected Qubits from a Possible Non-Abelian Fractional Quantum Hall State

The Pfaffian state is an attractive candidate for the observed quantized Hall plateau at Landau level filling fraction $\nu=5/2$. This is particularly intriguing because this state has unusual topological properties, including quasiparticle excitations with non-Abelian braiding statistics. In order to determine the nature of the $\nu=5/2$ state, one must measure the quasiparticle braiding statistics. Here, we propose an experiment which can simultaneously determine the braiding statistics of quasiparticle excitations and, if they prove to be non-Abelian, produce a topologically-protected qubit on which a logical NOT operation is performed by quasiparticle braiding. Using the measured excitation gap at $\nu=5/2$, we estimate the error rate to be $10^{-30}$ or lower

Interacting Hofstadter spectrum of atoms in an artificial gauge field

Motivated by experimental advances in the synthesis of gauge potentials for ultracold atoms, we consider the superfluid phase of interacting bosons on a square lattice in the presence of a magnetic field. We show that superfluid order implies spatial symmetry breaking, and predict clear signatures of many-body effects in time-of-flight measurements. By developing a Bogoliubov expansion based on the exact Hofstadter spectrum, we find the dispersion of the quasiparticle modes within the superfluid phase, and describe the consequences for Bragg spectroscopy measurements. The theory also provides an estimate of the critical interaction strength at the transition to the Mott insulator phase.Comment: 4+ pages, 2 figures; v2: published versio

Determining the sign of Δ31\Delta_{31} at long baseline neutrino experiments

Recently it is advocated that high intensity and low energy $(E_\nu \sim 2 GeV)$ neutrino beams should be built to probe the $(13)$ mixing angle $\phi$ to a level of a few parts in $10^4$. Experiments using such beams will have better signal to background ratio in searches for $\nu_\mu \to \nu_e$ oscillations. We propose that such experiments can also determine the sign of $\Delta_{31}$ even if the beam consists of {\it neutrinos} only. By measuring the $\nu_\mu \to \nu_e$ transitions in two different energy ranges, the effects due to propagation of neutrinos through earth's crust can be isolated and the sign of $\Delta_{31}$ can be determined. If the sensitivity of an experiment to $\phi$ is $\epsilon$, then the same experiment is automatically sensitive to matter effects and the sign of $\Delta_{31}$ for values of $\phi \geq 2 \epsilon$.Comment: Title changed and paper rewritten. 4 pages, 1 figure, revte

Calretinin expression in molecular subtypes of invasive carcinoma breast

Background: Breast cancer is a leading cause of cancer death  in women worldwide. Breast carcinoma is currently managed by assessing clinicopathological features. Elucidation of molecular mechanisms of pathogenesis of breast carcinoma  may lead to the development of new targeted therapies, particularly in triple negative cancers. Literature shows a few studies on the expression of calretinin  in breast carcinoma particularly in basal like type and its prognostic significance.  In this study, authors are trying  to assess the expression of  a new marker calretinin in different molecular subtypes of invasive carcinoma breast.Methods: This study was done in  107 cases of invasive carcinoma breast specimens received in  Department of Pathology, Government Medical college, Kottayam from December  2017 to May 2019.Results: Among the molecular subtypes, Basal like tumours showed 68.4% of cases with high level and 31.6% of cases with low level calretinin expression which is comparable with the study by Farrag et al. All the other molecular subgroups showed predominantly low level of calretinin expression.Conclusions: Different molecular subtypes of invasive carcinoma breast showed varied calretinin expression. High level calretinin expression was significantly associated with grade 3 (p value = 0.002), ER negativity (p = 0.004), PR negativity (p = 0.018)  and Basal like molecular subtype (p : <0.001). This suggests that calretinin might play a role in pathogenesis of basal like breast carcinomas

Real-space Manifestations of Bottlenecks in Turbulence Spectra

An energy-spectrum bottleneck, a bump in the turbulence spectrum between the inertial and dissipation ranges, is shown to occur in the non-turbulent, one-dimensional, hyperviscous Burgers equation and found to be the Fourier-space signature of oscillations in the real-space velocity, which are explained by boundary-layer-expansion techniques. Pseudospectral simulations are used to show that such oscillations occur in velocity correlation functions in one- and three-dimensional hyperviscous hydrodynamical equations that display genuine turbulence.Comment: 5 pages, 2 figure

Smooth analysis of the condition number and the least singular value

Let \a be a complex random variable with mean zero and bounded variance. Let $N_{n}$ be the random matrix of size $n$ whose entries are iid copies of \a and $M$ be a fixed matrix of the same size. The goal of this paper is to give a general estimate for the condition number and least singular value of the matrix $M + N_{n}$, generalizing an earlier result of Spielman and Teng for the case when \a is gaussian. Our investigation reveals an interesting fact that the "core" matrix $M$ does play a role on tail bounds for the least singular value of $M+N_{n}$. This does not occur in Spielman-Teng studies when \a is gaussian. Consequently, our general estimate involves the norm $\|M\|$. In the special case when $\|M\|$ is relatively small, this estimate is nearly optimal and extends or refines existing results.Comment: 20 pages. An erratum to the published version has been adde

Evaluation of Wound Healing Properties of Bioactive Fractions from the Extract of Butea monosperma (Lam) Stem Bark.

The study aims to evaluate the wound healing properties of bioactive fractions from the extract of Butea monosperma (Lam) stem bark. In this study the stem bark powder was extracted with ethanol, further the ethanolic extract was fractionated with different solvents (petroleum ether, benzene, chloroform and acetone) in increasing order of polarity. Thus prepared extracts were subjected to preliminary phytochemical analysis. The wound healing activity of the ethanolic extract and the fractions isolated from the stem bark of Butea monosperma were evaluated in excision, incision and dead space wound healing models using Albino wistar rats. The wound healing activity was assessed by the breaking strength in case of incision wounds, epithelialization and wound contraction in case of excision wound and granulation tissue dry weight, breaking strength and hydroxyproline content in case of dead space wound. The ethanolic extract and the acetone fraction showed the significant wound healing activity on all three wound models. The phytochemical investigations revealed the presence of alkaloids, tannins, flavonoids, phenolic compounds and steroids. The increased rate of wound contraction and hydroxyproline content in the ethanolic extract and the acetone fraction treated animals provides a scientific base to the ethno medicinal use of Butea monosperma, which is largely attributable to the additive or synergistic effect of their constituents. Keywords: Butea monosperma, Dead space wound, Excision wound, Incision wound

Occurrence, prevalence and molecular characterization of Norileca indica (Milne Edwards, 1840) (Isopoda: Cymothoidae) on bigeyescad Selar crumenophthalmus (Bloch) from Andaman Islands India

452-456The present investigation reports the occurrence and prevalence of the parasitic cymothoid, Norileca indica infesting bigeyescad, Selar crumenophthalmus from the Andaman Islands. Damage in the form of erosion of gill filament and necrosis in the gill chamber of the host fish, with a prevalence of 26.08% and a mean intensity of 1.5 is recorded. Molecular characterization of the mitochondrial COI and 28S rDNA genes is done to establish its phylogenetic status with its known congener. The present report is the first record of N. indica infesting S. crumenophthalmus from the Andaman Islands