Quantum tomography via equidistant states

We study the possibility of performing quantum state tomography via equidistant states. This class of states allows us to propose a non-symmetric informationally complete POVM based tomographic scheme. The scheme is defined for odd dimensions and involves an inversion which can be analytically carried out by Fourier transform

Effect of different micro-algae mixtures and rations in hatchery broodstock conditioning of the mussel Mytilus galloprovincialis.

Reproduction of the blue mussel Mytilus galloprovincialis in wild populations follows seasonal changes of environmental factors such as food availability.The aim of this experiment was to analyse the effects of three conditioning diets on the maturation and development of M. galloprovincialis. We experimented three different algae-based treatments: two Non-Tetraselmis (NT) groups and one Tetraselmis (TS) group. Those in the NT groups received a mixture of Isochrysis galbana (clon T-Iso) and Chaetoceros sp. (1:1, based on cell volume). Those in the TS group received Isochrysis sp. (T-Iso), Chaetoceros sp., and Tetraselmis suecica (1:1:1, based on cell volume). Mussels in the NT-1, NT-2 and TS groups received, respectively, 1%, 2% and 2% of the mussels dry weight (MDW) based in algae dry weight (ADW) a day. After 2 months of conditioning, significant changes between wild mussels and the NT-1 group were not detected either in condition index (CI) value or in gonad stadia percentages. On the opposite, after conditioning CI values of mussels having received 2 % ration were higher than those of wild populations and NT-1 group, and ripe female percentage was higher in the TS group than in the NT-2 group. As a conclusion, this study demonstrates that for M. galloprovincialis conditioning, 1% of the MDW in ADW is not enough, and that a varied diet is more suitable.This work was supported by Interreg Project 0251_ECOAQUA_5_E, financed by the EDRF (European Regional Development Fund). www.juntadeandalucia.es/agriculturaypesca/ifapa/ecoaqua.La reproducci&oacute;n del mejill&oacute;n Mytilus galloprovincialis en las poblaciones naturales sigue los cambios estacionales de factores ambientales como la disponibilidad de comida. El objetivo de este experimento fue analizar los efectos de tres dietas de acondicionamiento en la maduraci&oacute;n y el desarrollo de M. galloprovincialis. Para ello, se experimentaron tres tratamientos diferentes a base de microalgas: dos grupos sin la microalga Tetraselmis suecica (NT) y un tercero con esta microalga (TS). Los mejillones de los grupos NT recibieron una mezcla de Isochrysis galbana (clon T-Iso) y Chaetoceros sp. (1:1, basado en el volumen celular). Los del grupo de TS recibido I. galbana (clon T-Iso), Chaetoceros sp., y T. suecica (1:1:1, basado en el volumen celular). Los ejemplares de los grupos NT-1, NT-2 y TS recibieron, respectivamente, 1%, 2% y 2% del peso seco de la masa corporal (PSM) basado en el peso seco del fitoplancton (PSF) al d&iacute;a. Despu&eacute;s de 2 meses de acondicionamiento no se detectaron diferencias significativas en el valor del &iacute;ndice de condici&oacute;n (IC) ni en los porcentajes de estadios de madurez gonadal entre los mejillones del medio natural y el grupo NT-1. Sin embargo, despu&eacute;s del acondicionamiento valores del IC de los mejillones que recibieron el 2% de raci&oacute;n fueron superiores a los de las poblaciones del medio natural y el grupo NT-1. Adem&aacute;s, el porcentaje de hembras maduras fue mayor en el grupo TS que en el grupo NT-2. Como conclusi&oacute;n, este estudio demuestra que para el acondicionamiento de M. galloprovincialis un 1% de la PSM en PSF no es suficiente, y que una dieta variada es m&aacute;s adecuada.Este trabajo fue apoyado por el proyecto Interreg 0251_ECOAQUA_5_E , financiado por el FEDER (Fondo Europeo de Desarrollo Regional). www.juntadeandalucia.es / agriculturaypesca / IFAPA / ecoaqua. &nbsp;</p

A forced thermal ratchet in a memory heat bath

The present work studies a non-Markovian forced thermal ratchet model on an asymmetric periodic potential. The Brownian dynamics is described by a generalized Langevin equation with an Ornstein-Uhlenbeck-type friction memory kernel. We show that for the case of a time-dependent driving force, also in the form of an Ornstein-Uhlenbeck-like process, an exact expression of the probability current can be derived. We also obtain the behavior of the particle's average rate of flow as a function of the external amplitude force and of the bath temperature when the driving force behaves as a square wave modulation. All our results are compared with those obtained in the Markovian case and we find, fairly remarkably, that in some cases a friction memory kernel results in an enhancement of the curren

String Instabilities in Black Hole Spacetimes

We study the emergence of string instabilities in $D$ - dimensional black hole spacetimes (Schwarzschild and Reissner - Nordstr\o m), and De Sitter space (in static coordinates to allow a better comparison with the black hole case). We solve the first order string fluctuations around the center of mass motion at spatial infinity, near the horizon and at the spacetime singularity. We find that the time components are always well behaved in the three regions and in the three backgrounds. The radial components are {\it unstable}: imaginary frequencies develop in the oscillatory modes near the horizon, and the evolution is like $(\tau-\tau_0)^{-P}$, $(P>0)$, near the spacetime singularity, $r\to0$, where the world - sheet time $(\tau-\tau_0)\to0$, and the proper string length grows infinitely. In the Schwarzschild black hole, the angular components are always well - behaved, while in the Reissner - Nordstr\o m case they develop instabilities inside the horizon, near $r\to0$ where the repulsive effects of the charge dominate over those of the mass. In general, whenever large enough repulsive effects in the gravitational background are present, string instabilities develop. In De Sitter space, all the spatial components exhibit instability. The infalling of the string to the black hole singularity is like the motion of a particle in a potential $\gamma(\tau-\tau_0)^{-2}$ where $\gamma$ depends on the $D$ spacetime dimensions and string angular momentum, with $\gamma>0$ for Schwarzschild and $\gamma<0$ for Reissner - Nordstr\o m black holes. For $(\tau-\tau_0)\to0$ the string ends trapped by the black hole singularity.Comment: 26pages, Plain Te

Topological surface state under graphene for two-dimensional spintronics in air

Spin currents which allow for a dissipationless transport of information can be generated by electric fields in semiconductor heterostructures in the presence of a Rashba-type spin-orbit coupling. The largest Rashba effects occur for electronic surface states of metals but these cannot exist but under ultrahigh vacuum conditions. Here, we reveal a giant Rashba effect ({\alpha}_R ~ 1.5E-10 eVm) on a surface state of Ir(111). We demonstrate that its spin splitting and spin polarization remain unaffected when Ir is covered with graphene. The graphene protection is, in turn, sufficient for the spin-split surface state to survive in ambient atmosphere. We discuss this result along with evidences for a topological protection of the surface state.Comment: includes supplementary informatio

About the strength of correlation effects in the electronic structure of iron

The strength of electronic correlation effects in the spin-dependent electronic structure of ferromagnetic bcc Fe(110) has been investigated by means of spin and angle-resolved photoemission spectroscopy. The experimental results are compared to theoretical calculations within the three-body scattering approximation and within the dynamical mean-field theory, together with one-step model calculations of the photoemission process. This comparison indicates that the present state of the art many-body calculations, although improving the description of correlation effects in Fe, give too small mass renormalizations and scattering rates thus demanding more refined many-body theories including non-local fluctuations.Comment: 4 pages, 4 figure

Deformación plástica del antebrazo: revisión y caso clínico

La deformidad plástica de un hueso es una rara entidad, que en ocasiones pasa desapercibida. Se trata de una lesión típica del niño, con un hueso más elástico que los adultos. La mayoría de las deformidades plásticas del antebrazo se producen por caídas con el brazo en extensión, causando deformidad, dolor y una limitación de la pronosupinación. Para reducir la curvatura del hueso se precisan fuerzas contrarias a las que produjeron la lesión, mantenidas en el tiempo. En niños menores de 4 años, con enorme capacidad de remodelación, sólo grandes deformidades >20º deberían ser reducidas. En los mayores de 10 años, con escaso potencial remodelador, deben manipularse aquellas angulaciones >10-15º. La mayor complicación derivada de una mala reducción es la limitación de la pronosupinación, que en la mayoría de las ocasiones no altera la funcionalidad de la extremidad.Plastic bowing of a bone is a rare entity that some- times goes unnoticed. It’s a typical injury in children, who have more elastic bones than adults. Most of the plastic bowing of the forearm take place by falls with an outstretched arm, causing deformities, pain and a limitation of pronation and supination. In order to reduce the curvature of the bone, opposing forces to those that produced the injury are needed, maintained for a long time. In children younger than 4 years, with an enormous remodelling capacity, only great deformi- ties >20º should be reduced. For those older than 10 years, with little remodelling capacity, angulations >10-15º must be manipulated. The greatest complication derived from a bad reduction is the limitation of the pronation and supination, which in most cases does not modify the functionality of the extremity

Carnot, Stirling, Ericsson stochastic heat engines: Efficiency at maximum power

This work obtains the efficiency at maximum power for a stochastic heat engine performing Carnot-like, Stirling-like and Ericsson-like cycles. For the mesoscopic engine a Brownian particle trapped by an optical tweezers is considered. The dynamics of this stochastic engine is described as an overdamped Langevin equation with a harmonic potential, whereas is in contact with two thermal baths at different temperatures, namely, hot ($T_h$) and cold ($T_c$). The harmonic oscillator Langevin equation is transformed into a macroscopic equation associated with the mean value $\langle x^2(t)\rangle$ using the original Langevin approach. At equilibrium stationary state this quantity satisfies a state-like equation from which the thermodynamic properties are calculated. To obtained the efficiency at maximum power it is considered the finite-time cycle processes under the framework of low dissipation approach.Comment: 2 3pages, 5 figure