Collective oscillations in quantum rings: a broken symmetry case

We present calculations within density functional theory of the ground state and collective electronic oscillations in small two-dimensional quantum rings. No spatial symmetries are imposed to the solutions and, as in a recent contribution, a transition to a broken symmetry solution in the intrinsic reference frame for an increasingly narrow ring is found. The oscillations are addressed by using real-time simulation. Conspicuous effects of the broken symmetry solution on the spectra are pointed out.Comment: ReVTeX, 5 embedded eps, two gifs. Accepted in EPJ

Vigilancia Epidemiológica del VIH/SIDA. Situación en Europa y en España, 2013

[ES] En este boletín se presentan los principales resultados de la vigilancia de la infección por VIH/sida en España y en países de la Unión Europea y del Área Económica Europea (UE/AEE), correspondientes al año 2013. Este año se ha alcanzado por primera vez la cobertura nacional para el Sistema de vigilancia de nuevas infecciones por VIH, tanto en España como en los países de la UE. En 2013 la tasa de nuevos diagnósticos por VIH fue superior en España que en la UE/AEE (7,04/100.000 habitantes en España y 5,7 en la UE/AEE, sin corregir por retraso en la notificación) aunque similar a la de otros países del entorno. La vía de transmisión más importante sigue siendo la sexual, ocupando el primer lugar las relaciones sexuales no protegidas entre hombres. Los datos muestran, tanto en España como en la UE/AEE, que casi el 50% de las nuevas infecciones en 2013 presentaba indicios de diagnóstico tardío, por lo que es necesario incidir en la sensibilización de la población y los profesionales sanitarios para el diagnóstico precoz del VIH. [EN] This report shows the main findings about HIV/AIDS surveillance in Spain and European Union and European Economic Area countries (EU/EEA) in 2013. In 2013, for the first time, HIV surveillance data have national coverage in Spain and in all European countries. In 2013, the rate of HIV diagnoses was 7.04 per 100,000 population in Spain and 5.7 in EU/EEA, without adjusting by reporting delay. Sexual transmission is the predominant one, especially sex between men. In Spain as well in EU countries, almost 50% of new HIV cases in 2013 are delayed diagnoses. It is crucial to increase awareness in the general population and in health professionals for the early diagnoses of HIV infections. tN

Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

Caso de Rabia canina importada de Marruecos a España. Junio de 2013.

El 5 de junio de 2013, el servicio de epidemiología de Castilla-La Mancha notificó al Centro de Coordinación de Alertas y Emergencias Sanitarias (CCAES) un caso confirmado de rabia en un perro abatido por la policía en la ciudad de Toledo el 1 de junio. El animal había mordido a cuatro niños y un adulto. Uno de los niños requirió hospitalización e ingresó en la Unidad de Cuidados Intensivos. El Laboratorio Nacional de Referencia para lyssavirus realizó el diagnóstico por inmunofluorescencia, PCR y cultivo celular, así como la secuenciación genómica de la cepa del virus y su comparación con las cepas circulantes en países endémicos. Inmediatamente tras conocerse los resultados, los cuatro niños y el adulto recibieron profilaxis post-exposición con vacuna e inmunoglobulina1 . Las investigaciones preliminares revelaron que el perro había viajado con sus dueños el 22 de mayo desde Cataluña a una pequeña localidad a 10 km de Toledo. Según los dueños, el perro había escapado unos días antes de ser localizado en Toledo. En ese momento existía la sospecha, aún sin confirmar, de que el perro hubiera estado unos meses antes en Marruecos. España (territorio peninsular, Islas Baleares y Canarias) ha estado libre de rabia terrestre desde 1978. Tras recibir la notificación y según lo establecido en el Plan de Contingencia para el control de la rabia en España2 , se constituyó una comisión técnica formada por representantes de la Dirección General de Salud Pública, Calidad e Innovación del Ministerio de Sanidad, Servicios Sociales e Igualdad (DGSPCI), la Dirección General de Sanidad de la Producción Agrícola y Ganadera del Ministerio de Agricultura, Alimentación y Medio Ambiente (DGSPA), las Comunidades Autónomas afectadas, el Laboratorio Nacional de Referencia de rabia y el Centro Nacional de Epidemiología (CNE). Los objetivos de esta comisión eran coordinar la investigación del suceso, evaluar el riesgo para la salud humana y animal, proponer la activación de los correspondientes niveles de alerta y coordinar la aplicación de las medidas de control apropiadas.N

Ancestral Inference and the Study of Codon Bias Evolution: Implications for Molecular Evolutionary Analyses of the Drosophila melanogaster Subgroup

Reliable inference of ancestral sequences can be critical to identifying both patterns and causes of molecular evolution. Robustness of ancestral inference is often assumed among closely related species, but tests of this assumption have been limited. Here, we examine the performance of inference methods for data simulated under scenarios of codon bias evolution within the Drosophila melanogaster subgroup. Genome sequence data for multiple, closely related species within this subgroup make it an important system for studying molecular evolutionary genetics. The effects of asymmetric and lineage-specific substitution rates (i.e., varying levels of codon usage bias and departures from equilibrium) on the reliability of ancestral codon usage was investigated. Maximum parsimony inference, which has been widely employed in analyses of Drosophila codon bias evolution, was compared to an approach that attempts to account for uncertainty in ancestral inference by weighting ancestral reconstructions by their posterior probabilities. The latter approach employs maximum likelihood estimation of rate and base composition parameters. For equilibrium and most non-equilibrium scenarios that were investigated, the probabilistic method appears to generate reliable ancestral codon bias inferences for molecular evolutionary studies within the D. melanogaster subgroup. These reconstructions are more reliable than parsimony inference, especially when codon usage is strongly skewed. However, inference biases are considerable for both methods under particular departures from stationarity (i.e., when adaptive evolution is prevalent). Reliability of inference can be sensitive to branch lengths, asymmetry in substitution rates, and the locations and nature of lineage-specific processes within a gene tree. Inference reliability, even among closely related species, can be strongly affected by (potentially unknown) patterns of molecular evolution in lineages ancestral to those of interest

Ballistic conductance in kane type semiconductor quantum wire

The energy spectrum, ballistic conductance of an electron on the surface of a Kane type semiconductor hollow cylinder has been calculated by using the Kane equation with an additional term that takes into account the spin-orbit (SO) interaction. This term, known as Rashba term, occurs for asymmetric quantum wells, where two directions on the normal n are physically nonequivalent. If Rashba spin-orbital interaction is incorporated into energy spectrum, it leads to the emergence of new extrema. We obtained electron energy spectrum, which depends on the sign of the effective spin orbital constant. The energy spectrum of electrons has two branches when the magnetic field does not exist. One of these branches has only one minimum while the other branch has one maximum around k = 0 and two minima. The external magnetic field can control these extrema which occur in the event transport. The results were used to obtain the ballistic conductance at finite temperature of the Kane type hollow cylinder. It has been found that the presence of additional local extremum points in the subband of the electronic spectrum leads to a nonmonotonic dependence of the ballistic conductance of the system on the chemical potential. The g-factor of electrons was observed to depend on Rashba parameter in a linear manner. The effect of finite temperature smears out the sharp steps in the zero-temperature conductance

Technical Design Report for the Upgrade of the ALICE Inner Tracking System

ALICE (A Large Ion Collider Experiment) is preparing a major upgrade of its experimental apparatus, planned for installation in the second long LHC shutdown (LS2) in the years 2018-2019. These plans are presented in the ALICE Upgrade Letter of Intent submitted to the LHCC in September 2012. A key element of the upgrade is the construction of a new, ultra-light, high-resolution Inner Tracking System based on monolithic pixel detectors. This Technical Design Report is an update of the Conceptual Design Report for the Upgrade of the ALICE Inner Tracking System, which was presented to the LHCC in September 2012. The primary focus of the ITS upgrade is on the improved performance for detection of heavy-flavour hadrons, and of thermal photons and low-mass di-electrons emitted by the QGP. The Conceptual Design Report demonstrated that it is possible to build a new silicon tracker with greatly improved features in terms of determination of the distance of closest approach to the primary vertex, tracking efficiency at low transverse momenta, and read-out rate capabilities. This document presents an update of R&D activities, with particular focus on the technical implementation of the main detector components, and detector and physics performance. The detector performance and physics studies are based on Monte Carlo simulations that include the transport of particles in a detailed model of the new detector