On the theory of diamagnetism in granular superconductors

We study a highly disordered network of superconducting granules linked by weak Josephson junctions in magnetic field and develop a mean field theory for this problem. The diamagnetic response to a slow {\it variations} of magnetic field is found to be analogous to the response of a type-II superconductor with extremely strong pinning. We calculate an effective penetration depth $\lambda_g$ and critical current $j_c$ and find that both $\lambda_g^{-1}$ and $j_c$ are non-zero but are strongly suppressed by frustration.Comment: REVTEX, 12 pages, two Postscript figure

Medicaments: quin, quan, com...Projecte d’Aprenentatge i Servei per a secundària. Guia didàctica

Il·lustracions originals de Roser Bosch Mestres.La unitat didàctica que hem realitzat té com objectiu principal dissenyar un projecte d’Aprenentatge i Servei (APS) centrat en el bon ús dels medicaments. El projecte es caracteritza per ser una proposta educativa adreçada a joves d’ESO o de 1r curs de Batxillerat que combina activitats d’aprenentatge amb activitats de servei a la comunitat. Pensem que és un enfocament metodològic que ajuda a desenvolupar i a assolir determinades competències bàsiques, a la vegada que motiva l’alumnat, ja que es presenta un ensenyament contextualitzat i significatiu per a la comunitat. Els projectes d’APS responen a una necessitat concreta i rellevant de l’entorn social i, sempre que es pugui, ha d’implicar un acord de col·laboració entre diferents agents o institucions socials que possibilitin aquesta reciprocitat de beneficis d’aprenentatge i de servei. En aquest cas hem treballat com “partners” amb el Col·legi de farmacèutics, amb les farmàcies del barri i amb el SIGRE (responsable del reciclatge dels medicaments)

OECD/NEA PKL-4 benchmark activity. Code assessment of the relevant phenomena associated to a blind IBLOCA experiment

Code assessment and validation is one of the most relevant research lines in thermal hydraulics and best estimate codes. During the last decades, the Nuclear Energy Agency (NEA) and the Organization for Economic Co-operation and Development (OECD) have sponsored dozens of experimental projects in this field. Most of them were compiled in the CSNI Code Validation Matrix in 1996. Several projects have been promoted in the new century as the SETH, PKL, PKL-2, PKL-3 and PKL-4 at the PKL test facility. In 2017 a benchmark activity was launched within the framework of the OECD/NEA PKL-4 project with the aim of assessing the capabilities of system codes to reproduce the relevant phenomena associated to the IBLOCA scenario. 16 participant organizations from 9 different countries simulated the i2.2 (run 3) experiment in semi-blind conditions. A large variety of system codes were used in the activity: ATHLET, CATHARE, KORSAR, LOCUST, RELAP5, RELAPSCDASIM, SPACE and TRACE. This paper presents the main outcomes for the code assessment of such codes. The first part describes the main features of the experiment and the selection of the key phenomena for code validation. In addition, the paper intoduces a detailed description of each phenomena and the comparison between the experimental data and the blind simulations of the participants. Finally, in the last part of the paper the main sources of uncertainty associated to the codes and the modelling are listed as well as the code assessment conclusions of the benchmark activity. In general, the results obtained by all participants showed a good performance and satisfactory agreement with experimental data, which increases the confidence in current TH code technologies. The overall quality of the contributions was partly a consequence of the excellent documentation and information provided by the PKL team.Peer ReviewedPostprint (published version

Phase space geometry and slow dynamics

We describe a non-Arrhenius mechanism for slowing down of dynamics that is inherent to the high dimensionality of the phase space. We show that such a mechanism is at work both in a family of mean-field spin-glass models without any domain structure and in the case of ferromagnetic domain growth. The marginality of spin-glass dynamics, as well as the existence of a `quasi equilibrium regime' can be understood within this scenario. We discuss the question of ergodicity in an out-of equilibrium situation.Comment: 23 pages, ReVTeX3.0, 6 uuencoded postscript figures appende

On the Out of Equilibrium Relaxation of the Sherrington - Kirkpatrick model

We derive analytical results for the large-time relaxation of the Sherrington - Kirkpatrick model in the thermodynamic limit, starting from a random configuration. The system never achieves local equilibrium in any fixed sector of phase-space, but remains in an asymptotic out of equilibrium regime. We propose as a tool, both numerical and analytical, for the study of the out of equilibrium dynamics of spin-glass models the use of `triangle relations' which describe the geometry of the configurations at three (long) different times.Comment: 42 Pages + 3 Figures upon reques

Medicamentos: cuál, cuándo, cómo. Proyecto de Aprendizaje y Servicio para secundaria. Guía didáctica.

La unidad didáctica que hemos realizado tiene como objetivo principal diseñar un proyecto de Aprendizaje y Servicio (APS) centrado en el uso adecuado de los medicamentos. El proyecto se caracteriza por ser una propuesta educativa dirigida a jóvenes de ESO o de primer curso de Bachillerato que combina actividades de aprendizaje con actividades de servicio a la comunidad. El enfoque metodológico de esta unidad didáctica ayudará a desarrollar y alcanzar determinadas competencias básicas, al tiempo que motivará al alumnado, ya que se presenta una enseñanza contextualizada y significativa para la comunidad. Los proyectos de APS responden a una necesidad concreta y relevante del entorno social y, siempre que se pueda, deben implicar un acuerdo de colaboración entre distintos agentes o instituciones sociales que posibiliten esta reciprocidad de beneficios de aprendizaje y servicio. En este caso, hemos trabajado como partners con el Colegio de Farmacéuticos de Barcelona, las farmacias de barrio y SIGRE Medicamento y Medio Ambiente (entidad sin ánimo de lucro responsable del reciclado de los envases y restos de medicamentos de origen domiciliario). Hemos decidido centrarnos en el ámbito del «uso de los medicamentos», un ámbito de actuación que favorece en especial el aprendizaje y la aplicación de conocimientos del currículo de ciencias, puesto que estamos convencidos de la importancia de que la escuela forme a los jóvenes para ser competentes (lúcidos, eficientes y responsables) en dicho aspecto, de gran transcendencia para la salud, en la esfera personal, familiar y social, así como para el medio ambiente. El objetivo principal del proyecto es tomar consciencia de la importancia de utilizar correctamente los medicamentos, tanto desde el punto de vista de la salud como del medio ambiente. Para lograrlo se han diseñado actividades de enseñanza/aprendizaje de tipo «experiencial», en el sentido de que los alumnos se impliquen y puedan adquirir y aplicar conocimientos en distintos contextos. Hemos diseñado distintas actividades: estudio de casos, trabajo cooperativo, análisis de etiquetas de medicamentos, reciclado de los medicamentos en el domicilio y en la escuela, organización del contenido adecuado de un botiquín doméstico, entre otras. En cuanto a lo referente al servicio, se propone la revisión del botiquín de casa y de la escuela, así como acudir al punto SIGRE de la farmacia a llevar los medicamentos que ya no se utilicen o estén caducados, tanto si están vacíos como no. Además, se sugieren otras actividades, como una campaña de sensibilización para los compañeros y demás escuelas de niveles inferiores, en la que se haga referencia a cuáles son los medicamentos básicos necesarios en un botiquín, pero también se argumente la necesidad de realizar una recogida especial de los mismos, relacionándolo con el medio ambiente Este proyecto se puede aplicar tanto a 3º de ESO por el tema de Salud y enfermedades, como a 1º de Bachillerato, dentro de la materia Ciencias para el Mundo Contemporáneo

Sensitivity of a tonne-scale NEXT detector for neutrinoless double beta decay searches

The Neutrino Experiment with a Xenon TPC (NEXT) searches for the neutrinoless double-beta decay of Xe-136 using high-pressure xenon gas TPCs with electroluminescent amplification. A scaled-up version of this technology with about 1 tonne of enriched xenon could reach in less than 5 years of operation a sensitivity to the half-life of neutrinoless double-beta decay decay better than 1E27 years, improving the current limits by at least one order of magnitude. This prediction is based on a well-understood background model dominated by radiogenic sources. The detector concept presented here represents a first step on a compelling path towards sensitivity to the parameter space defined by the inverted ordering of neutrino masses, and beyond.Comment: 22 pages, 11 figure

Review of current Severe Accident Management (SAM) approaches for Nuclear Power Plants in Europe

The Fukushima accidents highlighted that both the in-depth understanding of such sequences and the development or improvement of adequate Severe Accident Management (SAM) measures are essential in order to further increase the safety of the nuclear power plants operated in Europe. To support this effort, the CESAM (Code for European Severe Accident Management) R&D project, coordinated by GRS, started in April 2013 for 4 years in the 7th EC Framework Programme of research and development of the European Commission. It gathers 18 partners from 12 countries: IRSN, AREVA NP SAS and EDF (France), GRS, KIT, USTUTT and RUB (Germany), CIEMAT (Spain), ENEA (Italy), VUJE and IVS (Slovakia), LEI (Lithuania), NUBIKI (Hungary), INRNE (Bulgaria), JSI (Slovenia), VTT (Finland), PSI (Switzerland), BARC (India) plus the European Commission Joint Research Center (JRC). The CESAM project focuses on the improvement of the ASTEC (Accident Source Term Evaluation Code) computer code. ASTEC,, jointly developed by IRSN and GRS, is considered as the European reference code since it capitalizes knowledge from the European R&D on the domain. The project aims at its enhancement and extension for use in severe accident management (SAM) analysis of the nuclear power plants (NPP) of Generation II-III presently under operation or foreseen in near future in Europe, spent fuel pools included. In the frame of the CESAM project one of the tasks consisted in the preparation of a report providing an overview of the Severe Accident Management (SAM) approaches in European Nuclear Power Plants to serve as a basis for further ASTEC improvements. This report draws on the experience in several countries from introducing SAMGs and on substantial information that has become available within the EU “stress test”. To disseminate this information to a broader audience, the initial CESAM report has been revised to include only public available information. This work has been done with the agreement and in collaboration with all the CESAM project partners. The result of this work is presented here.JRC.F.5-Nuclear Reactor Safety Assessmen