Matter-wave 2D solitons in crossed linear and nonlinear optical lattices

It is demonstrated the existence of multidimensional matter-wave solitons in a crossed optical lattice (OL) with linear OL in the $x-$direction and nonlinear OL (NOL) in the $y-$direction, where the NOL can be generated by a periodic spatial modulation of the scattering length using an optically induced Feshbach resonance. In particular, we show that such crossed linear and nonlinear OL allows to stabilize two-dimensional (2D) solitons against decay or collapse for both attractive and repulsive interactions. The solutions for the soliton stability are investigated analytically, by using a multi-Gaussian variational approach (VA), with the Vakhitov-Kolokolov (VK) necessary criterion for stability; and numerically, by using the relaxation method and direct numerical time integrations of the Gross-Pitaevskii equation (GPE). Very good agreement of the results corresponding to both treatments is observed.Comment: 8 pages (two-column format), with 16 eps-files of 4 figure

The quantized Hall conductance of a single atomic wire: A proposal based on synthetic dimensions

We propose a method by which the quantization of the Hall conductance can be directly measured in the transport of a one-dimensional atomic gas. Our approach builds on two main ingredients: (1) a constriction optical potential, which generates a mesoscopic channel connected to two reservoirs, and (2) a time-periodic modulation of the channel, specifically designed to generate motion along an additional synthetic dimension. This fictitious dimension is spanned by the harmonic-oscillator modes associated with the tightly-confined channel, and hence, the corresponding "lattice sites" are intimately related to the energy of the system. We analyze the quantum transport properties of this hybrid two-dimensional system, highlighting the appealing features offered by the synthetic dimension. In particular, we demonstrate how the energetic nature of the synthetic dimension, combined with the quasi-energy spectrum of the periodically-driven channel, allows for the direct and unambiguous observation of the quantized Hall effect in a two-reservoir geometry. Our work illustrates how topological properties of matter can be accessed in a minimal one-dimensional setup, with direct and practical experimental consequences.

Density dependent gauge field inducing emergent SSH physics, solitons and condensates in a discrete nonlinear Schr\"odinger equation

We investigate a discrete non-linear Schr\"odinger equation with dynamical, density-difference-dependent, gauge fields. We find a ground-state transition from a plane wave condensate to a localized soliton state as the gauge coupling is varied. Interestingly we find a regime in which the condensate and soliton are both stable. We identify an emergent chiral symmetry, which leads to the existence of a symmetry protected zero energy edge mode. The emergent chiral symmetry relates low and high energy solitons. These states indicate that the interaction acts both repulsively and attractively

Reversible effect of magnetic fields on human lymphocyte activation patterns: different sensitivity of naive and memory lymphocyte subsets.

The aim of this study was to investigate the influence of 50 Hz magnetic or static magnetic fields of 0.5 mT on subsets of human CD4+ T cells in terms of cytokine release/content, cell proliferation and intracellular free calcium concentration. CD4+ T cells can be divided into different subsets on the basis of surface marker expression, such as CD45, and T cells can be divided into naive (CD45RA+) and memory (CD45RA2) cells. In this study, the effects of magnetic fields after 24 and 48 h of cell culture were analyzed. We found that the CD4+CD45RA2 T subset were more sensitive after 2 h of exposure. Decreases in the release/content of IFN-c, in cell proliferation and in intracellular free calcium concentrations were observed in exposed CD4+CD45RA2 T cells compared to CD4+CD45RA+ T cells. The results suggest that exposure to the magnetic fields induces a delay in the response to stimulants and that modifications are rapidly reversible, at least after a short exposure

Base sequence dependent sliding of proteins on DNA

The possibility that the sliding motion of proteins on DNA is influenced by the base sequence through a base pair reading interaction, is considered. Referring to the case of the T7 RNA-polymerase, we show that the protein should follow a noise-influenced sequence-dependent motion which deviate from the standard random walk usually assumed. The general validity and the implications of the results are discussed.Comment: 12 pages, 3 figure

Laryngeal Candidiasis Mimicking Supraglottic Carcinoma by Prolonged Inhaled Steroid Therapy: A Case Report and Review of the Literature

Candidiasis is a rare entity reported as an isolated and primary laryngeal disease. In this condition, inhaled steroids were the single most common predisposing factor. Also mycotic infections of larynx are frequently seen in patients with immune insufficiency, although they have also been reported in individual with normal immune status. We report a case of isolated laryngeal Candidiasis in an immunocompetent individual, with an unusual presentation with exophytic lesion, edema, ulceration, white plaque, and pseudomembranous formation mimicking supraglottic carcinoma, to highlight the clinical of this condition and provide a review of the literature

Poopćenje potencijskog zakona za proučavanje dinamičkih sustava

We present a more general description of the technique of Tsallis and co-workers, to study the behaviour of dynamical systems. We enlarge to any dimension the power-law generalization of the classical Lyapunov exponents, that was introduced by Tsallis and co-workers in one dimension. We apply the new generalization to the two-dimensional Hénon map and consider some cases.Izlažemo poopćen opis metode Tsallisa i sur. za proučavanje svojstava dinamičkih sustava. Proširujemo poopćenje potencijskog zakona klasičnih Lyapunovih eksponenata na proizvoljan broj dimenzija po uzoru na poopćenje koje su uveli Tsallis i sur. za jednu dimenziju. Primjenjujemo to poopćenje na dvodimenzijsku Henonovu mapu i razmatramo neke slučajeve