Seismotectonic characterization of the Becerreá area (NW Spain)

The NW sector of the Iberian Peninsula has been classically considered as a seismically stable area, with only dispersed and low-magnitude activity. Around the village of Becerreá (Lugo) a significant concentration of earthquakes is observed. Since the beginning of instrumental record in 1979, seven seismic crisis have been reported in that zone, including 14 events of magnitude >4 and a larger event of magnitude 5.1mbLg (VII EMS) in 1997. Even if this seismicity is to be related to the general compressive regime between Africa and Eurasia, the seismotectonic characterization of the area is still controversial, as the different hypotheses considered are based on insufficiently accurate data. New insights to the problem are discussed here, coming from the deployment of a seismic portable network between 1999 and 2002, which has provided new accurate seismic data. The corresponding events are distributed around a subvertical axis, reaching a depth of 12km, and epicentres tend to concentrate beneath the intersection of the main Becerreá fault and secondary, ENE/WSW oriented faults. This intersection structure is thus interpreted as being responsible for the relatively high level of seismic activity over the area

CO72 357. Reconstrucción del cuerpo fibroso mitroaórtico: Resultados perioperatorios y supervivencia a largo plazo

ObjetivosDescribir las características clínicas, resultados perioperatorios y supervivencia a largo plazo de pacientes sometidos a sustitución valvular mitral y aórtica con reconstrucción de la fbrosa mitroaórtica según técnica de David.MétodosRevisión retrospectiva de pacientes sometidos a sustitución valvular y reconstrucción de la fibrosa mitroaórtica intervenidos en los últimos 14 años. Se incluyen 27 pacientes, 63% varones, edad 55,3±16,1 años, EuroSCORE 34,4±25,9. El 70,4% de los pacientes presentaban al menos una cirugía previa. La indicación para el procedimiento fue endocarditis infecciosa complicada con absceso de la unión mitroaórtica en el 74,1%; en el restante 25,9% la principal indicación fue la necesidad de ampliación del anillo aórtico en el seno de una valvulopatía mitroaórtica.ResultadosLa supervivencia perioperatoria (30 días) fue del 85,2%. No se observó mortalidad entre los pacientes sin endocarditis. Estancia media: 42,8±42,8 días. Complicaciones perioperatorias: accidente cerebrovascular agudo (ACVA) 3,1% (1), balón de contrapulsación intraaórtica (BCIA) 11,1% (3), insuficiencia renal aguda (IRA) 7,4% (2), infarto agudo de miocardio (IAM) 3,7% (1), reintervención por sangrado 14,8% (4), ventilación mecánica prolongada 11,1% (3), necesidad de marcapasos (MP) definitivo 22,2%. La supervivencia acumulada para los supervivientes a 1, 3 y 5 años fue de 85,9±7,6%, 75,8 ± 9,5% y 45,5 ± 11,1%, respectivamente. No se observó diferencia significativa al comparar la super-vivencia a 1, 3 y 5 años entre los grupos intervenidos por endocarditis y los no endocarditis (log rank 0,146).ConclusionesLa reconstrucción de la fibrosa mitroaórtica mediante técnica de David representa una alternativa terapéutica para el manejo de patología compleja que involucra esta estructura. Hemos observado buenos resultados perioperatorios y a largo plazo teniendo en cuenta el perfil de alto riesgo de los pacientes que requieren este tipo de intervención

Restauració de les pedreres de roca calcària en clima Mediterrani: procés i avaluació

Postprint (published version

Do the Unidentified EGRET Sources Trace Annihilating Dark Matter in the Local Group?

In a cold dark matter (CDM) framework of structure formation, the dark matter haloes around galaxies assemble through successive mergers with smaller haloes. This merging process is not completely efficient, and hundreds of surviving halo cores, or {\it subhaloes}, are expected to remain in orbit within the halo of a galaxy like the Milky Way. While the dozen visible satellites of the Milky Way may trace some of these subhaloes, the majority are currently undetected. A large number of high-velocity clouds (HVCs) of neutral hydrogen {\it are} observed around the Milky Way, and it is plausible that some of the HVCs may trace subhaloes undetected in the optical. Confirming the existence of concentrations of dark matter associated with even a few of the HVCs would represent a dramatic step forward in our attempts to understand the nature of dark matter. Supersymmetric (SUSY) extensions of the Standard Model of particle physics currently suggest neutralinos as a natural well-motivated candidate for the non-baryonic dark matter of the universe. If this is indeed the case, then it may be possible to detect dark matter indirectly as it annihilates into neutrinos, photons or positrons. In particular, the centres of subhaloes might show up as point sources in gamma-ray observations. In this work we consider the possibility that some of the unidentified EGRET $\gamma$-ray sources trace annihilating neutralino dark matter in the dark substructure of the Local Group. We compare the observed positions and fluxes of both the unidentified EGRET sources and the HVCs with the positions and fluxes predicted by a model of halo substructure, to determine to what extent any of these three populations could be associated.Comment: 12 Pages, 4 figures, to appear in a special issue of ApSS. Presented at "The Multiwavelength Approach to Unidentified Gamma-Ray Sources" (Hong Kong, June 1 - 4, 2004; Conference organizers: K.S. Cheng and G.E. Romero

Virtual coupling potential for elastic scattering of 10,11^{10,11}Be on proton and carbon targets

International audienceThe 10;11Be(p,p) and (12C, 12C) reactions were analyzed to determine the in uence of the weak binding energies of exotic nuclei on their interaction potential. The elastic cross sections were measured at GANIL in inverse kinematics using radioactive 10;11Be beams produced at energies of 39:1 A and 38:4A MeV. The elastic proton scattering data were analyzed within the framework of the microscopic Jeukenne-Lejeune-Mahaux (JLM) nucleon-nucleus potential. The angular distributions are found to be best reproduced by reducing the real part of the microscopic optical potential, as a consequence of the coupling to the continuum. These effects modify deeply the elastic potential. Including the Virtual Coupling Potential (VCP), we show the ability of the general optical potentials to reproduce the data for scattering of unstable nuclei, using realistic densities. Finally, the concepts needed to develop a more general and microscopic approach of the VCP are discussed

Coupling effects in the elastic scattering of 6^{6}He on 12^{12}C

To study the effect of the weak binding energy on the interaction potential between a light exotic nucleus and a target, elastic scattering of 6He at 38.3 MeV/nucleon on a 12C target was measured at Grand Accélérateur National d'Ions Lourds (GANIL). The 6He beam was produced by fragmentation. The detection of the scattered particles was performed by the GANIL spectrometer. The energy resolution was good enough to separate elastic from inelastic scattering contributions. The measured elastic data have been analyzed within the optical model, with the real part of the optical potential calculated in the double-folding model using a realistic density-dependent nucleon-nucleon interaction and the imaginary part taken in the conventional Woods-Saxon (WS) form. A failure of the "bare" real folded potential to reproduce the measured angular distribution over the whole angular range suggests quite a strong coupling of the higher-order breakup channels to the elastic channel. To estimate the strength of the breakup effects, a complex surface potential with a repulsive real part (designed to simulate the polarization effects caused by the projectile breakup) was added to the real folded and imaginary WS potentials. A realistic estimate of the polarization potential caused by the breakup of the weakly bound 6He was made based on a parallel study of 6He+12C and 6Li+12C optical potentials at about the same energies

High precision position measurements at high counting rates with drift chambers and multi-hit electronics

11 pages, 7 figure

Unfolding of differential energy spectra in the MAGIC experiment

The paper describes the different methods, used in the MAGIC experiment, to unfold experimental energy distributions of cosmic ray particles (gamma-rays). Questions and problems related to the unfolding are discussed. Various procedures are proposed which can help to make the unfolding robust and reliable. The different methods and procedures are implemented in the MAGIC software and are used in most of the analyses.Comment: Submitted to NIM

Implementation of the Random Forest Method for the Imaging Atmospheric Cherenkov Telescope MAGIC

The paper describes an application of the tree classification method Random Forest (RF), as used in the analysis of data from the ground-based gamma telescope MAGIC. In such telescopes, cosmic gamma-rays are observed and have to be discriminated against a dominating background of hadronic cosmic-ray particles. We describe the application of RF for this gamma/hadron separation. The RF method often shows superior performance in comparison with traditional semi-empirical techniques. Critical issues of the method and its implementation are discussed. An application of the RF method for estimation of a continuous parameter from related variables, rather than discrete classes, is also discussed.Comment: 16 pages, 8 figure

Unsupervised system to classify SO2 pollutant concentrations in Salamanca, Mexico

Salamanca is cataloged as one of the most polluted cities in Mexico. In order to observe the behavior and clarify the influence of wind parameters on the Sulphur Dioxide (SO2) concentrations a Self-Organizing Maps (SOM) Neural Network have been implemented at three monitoring locations for the period from January 1 to December 31, 2006. The maximum and minimum daily values of SO2 concentrations measured during the year of 2006 were correlated with the wind parameters of the same period. The main advantages of the SOM Neural Network is that it allows to integrate data from different sensors and provide readily interpretation results. Especially, it is powerful mapping and classification tool, which others information in an easier way and facilitates the task of establishing an order of priority between the distinguished groups of concentrations depending on their need for further research or remediation actions in subsequent management steps. For each monitoring location, SOM classifications were evaluated with respect to pollution levels established by Health Authorities. The classification system can help to establish a better air quality monitoring methodology that is essential for assessing the effectiveness of imposed pollution controls, strategies, and facilitate the pollutants reduction