33 research outputs found

    V12 248. Reemplazo de raíz de aorta según técnica de david y de arco aórtico con injerto trifurcado, en un paciente diagnosticado de síndrome de loeys-dietz

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    IntroducciónSe describe la técnica quirúrgica de un paciente de 24 años de edad con síndrome de Loeys-Dietz. Se trata de una enfermedad hereditaria del tejido conectivo producida por la mutación del gen del receptor del factor de crecimiento transformante (TGF)-β;. Su característica principal y condicionante del pronóstico es la dilatación del sistema vascular, principalmente la aorta.MétodoEl paciente presentaba dilatación aneurismática de la raíz y del arco aórtico, con un diámetro máximo de 50 mm. Tenía además historia familiar de muerte súbita de origen cardíaco en tres familiares de primer grado a edades tempranas. Ante la indicación de tratamiento quirúrgico se procedió a realizar sustitución de los segmentos aneurismáticos. En la raíz aórtica se realizó técnica de preservación valvular (técnica de David, modificación de Miller). La sustitución del arco aórtico se llevó a cabo mediante interposición de injerto trifurcado, en hipotermia moderada y con perfusión cerebral anterógrada.Resultado y conclusionesNo hubo complicaciones postoperatorias. El tratamiento quirúrgico precoz en los pacientes afectos de síndrome de Loeys-Dietz es imprescindible. La experiencia acumulada hasta el momento revela la agresividad de esta enfermedad. Por ello, es necesario un abordaje completo cuando existe afectación a distintos niveles. El empleo de técnicas de preservación valvular permite además disminuir la morbimortalidad asociada a las prótesis valvulares

    Gravitational Waves From Known Pulsars: Results From The Initial Detector Era

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    We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom

    First searches for optical counterparts to gravitational-wave candidate events

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    During the Laser Interferometer Gravitational-wave Observatory and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers showed strong evidence for being astrophysical in nature. We compare the sensitivities of these observations to several model light curves from possible sources of interest, and discuss prospects for future joint GW-optical observations of this type

    FIRST SEARCHES FOR OPTICAL COUNTERPARTS TO GRAVITATIONAL-WAVE CANDIDATE EVENTS

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    During the LIGO and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers showed strong evidence for being astrophysical in nature. We compare the sensitivities of these observations to several model light curves from possible sources of interest, and discuss prospects for future joint GW-optical observations of this type

    Search for long-lived gravitational-wave transients coincident with long gamma-ray bursts

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    Long gamma-ray bursts (GRBs) have been linked to extreme core-collapse supernovae from massive stars. Gravitational waves (GW) offer a probe of the physics behind long GRBs. We investigate models of long-lived (~10–1000 s) GW emission associated with the accretion disk of a collapsed star or with its protoneutron star remnant. Using data from LIGO’s fifth science run, and GRB triggers from the Swift experiment, we perform a search for unmodeled long-lived GW transients. Finding no evidence of GW emission, we place 90% confidence-level upper limits on the GW fluence at Earth from long GRBs for three waveforms inspired by a model of GWs from accretion disk instabilities. These limits range from F<3:5 ergs cm⁻2 to F<1200 ergs cm⁻2, depending on the GRB and on the model, allowing us to probe optimistic scenarios of GW production out to distances as far as ≈ 33 Mpc. Advanced detectors are expected to achieve strain sensitivities 10× better than initial LIGO, potentially allowing us to probe the engines of the nearest long GRBs.J. Aasi ... D.J. Hosken ... W. Kim ... E.J. King ... J. Munch ... D. J. Ottaway ... P. J. Veitc

    Searching for stochastic gravitational waves using data from the two colocated LIGO Hanford detectors

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    Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among other things, on the separation between the two detectors: the smaller the separation, the better the sensitivity. Hence, a colocated detector pair is more sensitive to a gravitational-wave background than a noncolocated detector pair. However, colocated detectors are also expected to suffer from correlated noise from instrumental and environmental effects that could contaminate the measurement of the background. Hence, methods to identify and mitigate the effects of correlated noise are necessary to achieve the potential increase in sensitivity of colocated detectors. Here we report on the first SGWB analysis using the two LIGO Hanford detectors and address the complications arising from correlated environmental noise. We apply correlated noise identification and mitigation techniques to data taken by the two LIGO Hanford detectors, H1 and H2, during LIGO’s fifth science run. At low frequencies, 40–460 Hz, we are unable to sufficiently mitigate the correlated noise to a level where we may confidently measure or bound the stochastic gravitational-wave signal. However, at high frequencies, 460–1000 Hz, these techniques are sufficient to set a 95% confidence level upper limit on the gravitational-wave energy density of Ω(f) < 7.7 × 10[superscript -4](f/900  Hz)[superscript 3], which improves on the previous upper limit by a factor of ~180. In doing so, we demonstrate techniques that will be useful for future searches using advanced detectors, where correlated noise (e.g., from global magnetic fields) may affect even widely separated detectors.National Science Foundation (U.S.)United States. National Aeronautics and Space AdministrationCarnegie TrustDavid & Lucile Packard FoundationAlfred P. Sloan Foundatio

    Anales de Edafología y Agrobiología Tomo 27 Número 3-4

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    Oligoelementos en árboles de bosque (Pinus). IV. Estudio edafológico de las ocho parcelas forestales elegidas, por R. Lagunas-Gil, M. Deán-Guelbenzu, J. M. López de Azcona y A. Santos Ruiz.-- Representación de la curva de p F en papel probabilístieo, por R. Román Alba.-- Medida de los potenciales de raíz, por S. Oliver y T . Mendizábal.-- Deficiencias nutritivas en diversas repoblaciones le coníferas del centro de España por F. Complejos de adsorción de la vermiculita con dimctilsulfóxido, por M. Sánchez Camazano y S. González García .-- Los suelos de la provincia de Cáceres. III. Suelos sobre calizas y rocas ígneas básicas, por J. Forteza Bonnin, A. García Rodríguez, Mª Sánchez Camazano y Mª T. Martín Patino.-- Los suelos, de la provincia de Cáceres. IV. Suelos formados sobre sedimentos terciarios y cuaternarios por J. Forteza Bonnin, A. García Rodríguez, Mª Sánchez Camazano y Mª. T. Martin.-- Algunas observaciones sobre la evolución de las yemas del olivo (Ulea Europea L.), por A. Troncoso de Arce.-- Determinación potenciométrica de cloruros, por S. Oliver.-- Influencia de: césped sobre la estructura de suelo, por J. Benayas Casares y Mª Alonso Checa.-- Notas. Aniversario del fallecimiento del Prof. Albareda.-- Centros.-- Reestructuración del Instituto de Edafología y Biología Vegetal.-- Congresos, Reuniones internacionales y becas.-- Instituto de Orientación y Asistencia Técnica del Sureste.-- Departamento de Economía Agraria.-- Acuerdo del Excmo. Ayuntamiento de Jaca.-- Conferencia del Dr. N. R. Dhar.-- Conferencia sobre «Supresión del barbecho».-- Comisión Científica de Protección de la Naturaleza.-- V Congreso Internacional de la Detergencia.-- Nombramiento de becarios en los Centros del Instituto Nacional de Edafología y Agro Convocatoria del Premio Agrícola Aedos, 1968 biología «José María Albareda».-- BibliografíaPeer reviewe
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