6,304 research outputs found

    Draft Genome Sequences of Five Enterococcus Species Isolated from the Gut of Patients with Suspected Clostridium difficile Infection

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    Indexación: Scopus.We present draft genome sequences of five Enterococcus species from patients suspected of Clostridium difficile infection. Genome completeness was confirmed by presence of bacterial orthologs (97%). Gene searches using Hidden-Markov models revealed that the isolates harbor between seven and 11 genes involved in antibiotic resistance to tetracyclines, beta-lactams, and vancomycin.http://genomea.asm.org/content/5/20/e00379-17.ful

    New anallytic approximations based on the Magnus expansion

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    The Magnus expansion is a frequently used tool to get approximate analytic solutions of time-dependent linear ordinary differential equations and in particular the Schrödinger equation in quantum mechanics. However, the complexity of the expansion restricts its use in practice only to the first terms. Here we introduce new and more accurate analytic approximations based on the Magnus expansion involving only univariate integrals which also shares with the exact solution its main qualitative and geometric propertie

    Effects of the environment on galaxies in the Catalogue of Isolated Galaxies: physical satellites and large scale structure

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    We aim to identify and quantify the effects of the satellite distribution around a sample of galaxies in the Catalogue of Isolated Galaxies (CIG), as well as the effects of the Large Scale Structure (LSS) using the SDSS-DR9. To recover the physically bound galaxies we focus on the satellites which are within the escape speed of each CIG galaxy. We also propose a more conservative method using the stacked Gaussian distribution of the velocity difference of the neighbours. The tidal strengths affecting the primary galaxy are estimated to quantify the effects of the local and LSS environments. We also define the projected number density parameter at the 5th^{\rm th} nearest neighbour to characterise the LSS around the CIG galaxies. Out of the 386 CIG galaxies considered in this study, at least 340 (88\% of the sample) have no physically linked satellite. Out of the 386 CIG galaxies, 327 (85\% of the sample) have no physical companion within a projected distance of 0.3 Mpc. The CIG galaxies are distributed following the LSS of the local Universe, although presenting a large heterogeneity in their degree of connection with it. A clear segregation appears between early-type CIG galaxies with companions and isolated late-type CIG galaxies. Isolated galaxies are in general bluer, with likely younger stellar populations and rather high star formation with respect to older, redder CIG galaxies with companions. Reciprocally, the satellites are redder and with an older stellar populations around massive early-type CIG galaxies, while they have a younger stellar content around massive late-type CIG galaxies. This suggests that the CIG is composed of a heterogeneous population of galaxies, sampling from old to more recent, dynamical systems of galaxies.Comment: 19 pages, 10 figures, 1 table, accepted for publication in Astronomy & Astrophysic

    Photoelectrochemical characterization of anatase-rutile mixed TiO2 nanosponges

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    This work studies the influence of using hydrodynamic conditions during anodization on the morphology and electrochemical properties of anatase/rutile mixed TiO2 nanotubes (Reynolds number, Re = 0) and nanosponges (Re > 0). To this purpose different techniques were used, such as: microscopy techniques (Field-Emission Scanning Electron Microscope, FE-SEM, and Confocal Laser-Raman Spectroscopy), Electrochemical Impedance Spectroscopy (EIS), Mott Schottky (MS) analysis and photoelectrochemical water splitting tests. This investigation demonstrates that the morphology of TiO2 nanostructures may be greatly affected due to the hydrodynamic conditions and it can be adjusted in order to increase the efficiency for energy and environmental applications

    Oligomerización de receptores acoplados a proteína G y enfermedad de Parkinson

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    La enfermedad de Parkinson es una condición neurodegenerativa del sistema nervioso central que puede aparecer en la madurez pero cuya incidencia aumenta dramáticamente en la tercera edad. Por este motivo, en las sociedades industrializadas, donde la esperanza de vida es alta, la enfermedad tiene un elevado coste socio-económico. El origen de la patología radica en la pérdida selectiva de neuronas dopaminérgicas de una región concreta de los ganglios basales. En consecuencia, se produce un desequilibrio neuroquímico (ej.; glutama to/dopamina/adenosina) que afecta en última instancia a los procesos controlados por los ganglios basales (ej.; el control motor, la cognición, las emociones y el aprendizaje). Recientemente, se ha demostrado que los receptores acoplados a proteína G pueden expresarse en la membrana plasmática como homodímeros y heterómeros. Estos complejos oligoméricos pueden funcionar como procesadores computacionales dinámicos, modulando la señalización celular y por tanto el flujo de información a través de los circuitos neuronales. Así, desde un punto de vista cuantitativo y/o cualitativo la señal generada por la estimulación de un receptor concreto del heterómero puede ser diferente de aquella obtenida mediante la coestimulación de los diferentes integrantes del complejo. Este nuevo concepto, además de exhortar la reinterpretación de la farmacodinámica clásica de receptores acoplados a proteína G, impulsará el diseño de nuevas terapias basadas en la combinación de fármacos cuya diana sean los oligómeros de receptores, por ejemplo, el oligómero formado por los receptores de glutamato, dopamina y adenosina en el tratamiento de la enfermedad de Parkinson

    The cosmic evolution of the spatially-resolved star formation rate and stellar mass of the CALIFA survey

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    We investigate the cosmic evolution of the absolute and specific star formation rate (SFR, sSFR) of galaxies as derived from a spatially-resolved study of the stellar populations in a set of 366 nearby galaxies from the CALIFA survey. The analysis combines GALEX and SDSS images with the 4000 break, H_beta, and [MgFe] indices measured from the datacubes, to constrain parametric models for the SFH, which are then used to study the cosmic evolution of the star formation rate density (SFRD), the sSFR, the main sequence of star formation (MSSF), and the stellar mass density (SMD). A delayed-tau model, provides the best results, in good agreement with those obtained from cosmological surveys. Our main results from this model are: a) The time since the onset of the star formation is larger in the inner regions than in the outer ones, while tau is similar or smaller in the inner than in the outer regions. b) The sSFR declines rapidly as the Universe evolves, and faster for early than for late type galaxies, and for the inner than for the outer regions of galaxies. c) SFRD and SMD agree well with results from cosmological surveys. At z< 0.5, most star formation takes place in the outer regions of late spiral galaxies, while at z>2 the inner regions of the progenitors of the current E and S0 are the major contributors to SFRD. d) The inner regions of galaxies are the major contributor to SMD at z> 0.5, growing their mass faster than the outer regions, with a lookback time at 50% SMD of 9 and 6 Gyr for the inner and outer regions. e) The MSSF follows a power-law at high redshift, with the slope evolving with time, but always being sub-linear. f) In agreement with galaxy surveys at different redshifts, the average SFH of CALIFA galaxies indicates that galaxies grow their mass mainly in a mode that is well represented by a delayed-tau model, with the peak at z~2 and an e-folding time of 3.9 Gyr.Comment: 23 pages, 16 figures, 6 tables, accepted for publication in Astronomy & Astrophysics. *Abridged abstract

    BCYCLIC: A parallel block tridiagonal matrix cyclic solver

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    13 pages, 6 figures.A block tridiagonal matrix is factored with minimal fill-in using a cyclic reduction algorithm that is easily parallelized. Storage of the factored blocks allows the application of the inverse to multiple right-hand sides which may not be known at factorization time. Scalability with the number of block rows is achieved with cyclic reduction, while scalability with the block size is achieved using multithreaded routines (OpenMP, GotoBLAS) for block matrix manipulation. This dual scalability is a noteworthy feature of this new solver, as well as its ability to efficiently handle arbitrary (non-powers-of-2) block row and processor numbers. Comparison with a state-of-the art parallel sparse solver is presented. It is expected that this new solver will allow many physical applications to optimally use the parallel resources on current supercomputers. Example usage of the solver in magneto-hydrodynamic (MHD), three-dimensional equilibrium solvers for high-temperature fusion plasmas is cited.This research has been sponsored by the US Department of Energy under Contract DE-AC05-00OR22725 with UT-Battelle, LLC. This research used resources of the National Center for Computational Sciences at Oak Ridge National Laboratory, which is supported by the Office of Science of the Department of Energy under Contract DE-AC05-00OR22725.Publicad

    Paleopatología dental de siete cabezas egipcias momificadas del Museo de Antropología Forense de la Univ. Complutense de Madrid

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    X Congreso Nacional de Paleopatología. Univesidad Autónoma de Madrid, septiembre de 200
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