Chiral Bogoliubons in Nonlinear Bosonic Systems

We present a versatile scheme for creating topological Bogoliubov excitations in weakly interacting bosonic systems. Our proposal relies on a background stationary field that consists of a Kagome vortex lattice, which breaks time-reversal symmetry and induces a periodic potential for Bogoliubov excitations. In analogy to the Haldane model, no external magnetic field or net flux is required. We construct a generic model based on the two-dimensional (2D) nonlinear Schr\"odinger equation and demonstrate the emergence of topological gaps crossed by chiral Bogoliubov edge modes. Our scheme can be realized in a wide variety of physical systems ranging from nonlinear optical systems to exciton-polariton condensates.Comment: 6 pages, 3 figures; with Supplemental Material (5 pages; in source

Report on Morphinism to the Municipal Court of Boston

"Reprinted from the Journal of criminal law and criminology, Vol. 13, no. 1, May, 1922."Caption title.Bibliography: p. 54-[55]Mode of access: Internet

Topological Polaritons and Excitons in Garden Variety Systems

Topological polaritons (aka topolaritons) present a new frontier for topological behavior in solid-state systems. They combine light and matter, which allows to probe and manipulate them in a variety of ways. They can also be made strongly interacting, due to their excitonic component. So far, however, their realization was deemed rather challenging. Here we present a scheme which allows to realize topolaritons in garden variety zinc-blende quantum wells. Our proposal requires a moderate magnetic field and a potential landscape which can be implemented, e.g., via surface acoustic waves or patterning. We identify indirect excitons in double quantum wells as a particularly appealing alternative for topological states in exciton-based systems. Indirect excitons are robust and long lived (with lifetimes up to milliseconds), and, therefore, provide a flexible platform for the realization, probing, and utilization of topological coupled light-matter states.Comment: 6 pages, 4 figures; v2: improved figures and text, with added details regarding achievable topological gap

Numerical optimization of hybrid dielectric/HTS resonators for surface impedance evaluation of HTS films

This work describes an alternative to the traditional dielectric resonator topology used for measuring surface impedance in high temperature superconducting (HTS) films. A gap is introduced above the dielectric so that only the lower film is in direct contact with it. This arrangement has been used extensively for mechanical tuning of dielectric resonators and, when used for surface impedance measurement, it can be designed to make the losses in the upper film small relative to the overall resonator losses. Then, measured results are mostly due to one of the films and not the average of two. The specifics of a resonator design for measuring 2-inch wafers are presented. An analysis and optimization of the resonator is done using a numerically efficient mode-matching algorithm.Peer ReviewedPostprint (published version

Implications of the Dirac CP phase upon parametric resonance for sub-GeV neutrinos

We perform an analytic and numerical study of parametric resonance in a three-neutrino framework for sub-GeV neutrinos which travel through a periodic density profile. Commensurate with the initial level of approximation, we develop a parametric resonance condition similar to the exact condition for two-neutrino systems. For a castle-wall density profile, the νe→νμ oscillation probability is enhanced significantly and bounded by cos2θ23. The CP phase δ enters into the oscillation probability as a phase shift. For several cases, we examine the interplay between the characteristics of the castle-wall profile and the CP phase and determine which profiles maximize the separation between oscillations with δ=0,±π2,π. We also consider neutrinos which travel along a chord through the Earth, passing from the mantle to core and back to mantle again. Significant enhancement of the oscillation probability is seen even in the case in which the neutrino energy is far from the MSW resonant energies. At 500 GeV, the difference between oscillation probabilities with δ=0 and δ=π2 is maximized

Evolution and predictive factors of relapse in ulcerative colitis patients treated with mesalazine after a first course of corticosteroids.

INTRODUCTION: Mesalazine remains the first line treatment for the induction and the maintenance of remission in mild to moderate ulcerative colitis (UC). Its efficacy as a maintenance treatment after a first flare treated with corticosteroids has not been specifically studied. The aims of our work were to study a cohort of UC patients treated with mesalazine after a course of oral systemic corticosteroids and to identify predictive factors of relapse and of colectomy. MATERIAL AND METHOD: We studied retrospectively a cohort of 143 UC patients, who never received immunosuppressive drugs, and treated for the first time with oral corticosteroids for a flare. Among patients responding to corticosteroids, we studied the group treated by mesalazine after the flare. RESULTS: Fifty% (n=52) achieved a complete clinical remission with steroid weaning. In this group, 67% (n=35) received oral mesalazine. Seventy-five % of patients treated by mesalazine relapsed (median 29 months, range: 1-156). Fourteen % required a colectomy (median 11 months, range: 1-24). Kaplan Meier curve showed a relapse rate and a colectomy rate over one year of 26% and 11% respectively. In multivariate analysis, male gender and short duration of disease were predictive factors of the time-to-relapse. No factor was predictive of time-to-colectomy. CONCLUSION: Maintenance efficacy of mesalazine over one year after a first course of corticosteroids for a disease flare is reasonably high. The longer-term relapse rate becomes higher in male patients with a short disease duration. An immunosuppressive treatment could be discussed in case of further relapse despite improved medication-adherence. Medication-adherence should first be assessed and promoted. An immunosuppressive treatment could be discussed in case of further relapse despite improved medication-adherence

Control and Manipulation of Cold Atoms in Optical Tweezers

Neutral atoms trapped by laser light are amongst the most promising candidates for storing and processing information in a quantum computer or simulator. The application certainly calls for a scalable and flexible scheme for addressing and manipulating the atoms. We have now made this a reality by implementing a fast and versatile method to dynamically control the position of neutral atoms trapped in optical tweezers. The tweezers result from a spatial light modulator (SLM) controlling and shaping a large number of optical dipole-force traps. Trapped atoms adapt to any change in the potential landscape, such that one can re-arrange and randomly access individual sites within atom-trap arrays.Comment: 6 pages, 4 figure

Mechanically-driven Stem Cell Separation in Tissues caused by Proliferating Daughter Cells

The homeostasis of epithelial tissue relies on a balance between the self-renewal of stem cell populations, cellular differentiation, and loss. Although this balance needs to be tightly regulated to avoid pathologies, such as tumor growth, the regulatory mechanisms, both cell-intrinsic and collective, which ensure tissue steady-state are still poorly understood. Here, we develop a computational model that incorporates basic assumptions of stem cell renewal into distinct populations and mechanical interactions between cells. We find that the model generates unexpected dynamic features: stem cells repel each other in the bulk tissue and are thus found rather isolated, as in a number of in vivo contexts. By mapping the system onto a gas of passive Brownian particles with effective repulsive interactions, that arise from the generated flows of differentiated cells, we show that we can quantitatively describe such stem cell distribution in tissues. The interaction potential between a pair of stem cells decays exponentially with a characteristic length that spans several cell sizes, corresponding to the volume of cells generated per stem cell division. Our findings may help understanding the dynamics of normal and cancerous epithelial tissues

Characteristic polynomials of random matrices at edge singularities

We have discussed earlier the correlation functions of the random variables \det(\la-X) in which $X$ is a random matrix. In particular the moments of the distribution of these random variables are universal functions, when measured in the appropriate units of the level spacing. When the \la's, instead of belonging to the bulk of the spectrum, approach the edge, a cross-over takes place to an Airy or to a Bessel problem, and we consider here these modified classes of universality. Furthermore, when an external matrix source is added to the probability distribution of $X$, various new phenomenons may occur and one can tune the spectrum of this source matrix to new critical points. Again there are remarkably simple formulae for arbitrary source matrices, which allow us to compute the moments of the characteristic polynomials in these cases as well.Comment: 22 pages, late

Chiral Bogoliubov excitations in nonlinear bosonic systems

We present a versatile scheme for creating topological Bogoliubov excitations in weakly interacting bosonic systems. Our proposal relies on a background stationary field that consists of a Kagome vortex lattice, which breaks time-reversal symmetry and induces a periodic potential for Bogoliubov excitations. In analogy to the Haldane model, no external magnetic field or net flux is required. We construct a generic model based on the two-dimensional (2D) nonlinear Schrödinger equation and demonstrate the emergence of topological gaps crossed by chiral Bogoliubov edge modes. Our scheme can be realized in a wide variety of physical systems ranging from nonlinear optical systems to exciton-polariton condensates