9,244 research outputs found

    Census of HII regions in NGC 6754 derived with MUSE: Constraints on the metal mixing scale

    Get PDF
    We present a study of the HII regions in the galaxy NGC 6754 from a two pointing mosaic comprising 197,637 individual spectra, using Integral Field Spectrocopy (IFS) recently acquired with the MUSE instrument during its Science Verification program. The data cover the entire galaxy out to ~2 effective radii (re ), sampling its morphological structures with unprecedented spatial resolution for a wide-field IFU. A complete census of the H ii regions limited by the atmospheric seeing conditions was derived, comprising 396 individual ionized sources. This is one of the largest and most complete catalogue of H ii regions with spectroscopic information in a single galaxy. We use this catalogue to derive the radial abundance gradient in this SBb galaxy, finding a negative gradient with a slope consistent with the characteristic value for disk galaxies recently reported. The large number of H ii regions allow us to estimate the typical mixing scale-length (rmix ~0.4 re ), which sets strong constraints on the proposed mechanisms for metal mixing in disk galaxies, like radial movements associated with bars and spiral arms, when comparing with simulations. We found evidence for an azimuthal variation of the oxygen abundance, that may be related with the radial migration. These results illustrate the unique capabilities of MUSE for the study of the enrichment mechanisms in Local Universe galaxies.Comment: 13 pages, 7 Figurs, accepted for publishing in A&

    Functional and molecular characterization of inherited platelet disorders in the Iberian Peninsula: results from a collaborative study

    Get PDF
    12 p.-6 tab. Sánchez-Guiu et al.[Background] The diagnostic evaluation of inherited platelet disorders (IPDs) is complicated and time-consuming, resulting in a relevant number of undiagnosed and incorrectly classified patients. In order to evaluate the spectrum of IPDs in individuals with clinical suspicion of these disorders, and to provide a diagnostic tool to centers not having access to specific platelets studies, we established the project “Functional and Molecular Characterization of Patients with Inherited Platelet Disorders” under the scientific sponsorship of the Spanish Society of Thrombosis and Haemostasis.[Patients/methods] Subjects were patients from a prospective cohort of individuals referred for clinical suspicion of IPDs as well as healthy controls. Functional studies included light transmission aggregation, flow cytometry, and when indicated, Western-blot analysis of platelet glycoproteins, and clot retraction analysis. Genetic analysis was mainly performed by sequencing of coding regions and proximal regulatory regions of the genes of interest.[Results] Of the 70 cases referred for study, we functionally and molecularly characterized 12 patients with Glanzmann Thrombasthenia, 8 patients with Bernard Soulier syndrome, and 8 with other forms of IPDs. Twelve novel mutations were identified among these patients. The systematic study of patients revealed that almost one-third of patients had been previously misdiagnosed.[Conclusions] Our study provides a global picture of the current limitations and access to the diagnosis of IPDs, identifies and confirms new genetic variants that cause these disorders, and emphasizes the need of creating reference centers that can help health care providers in the recognition of these defects.Research of the authors’ group is supported by the Instituto de Salud Carlos III (ISCIII, PI10/02594), RECAVA RD12/0042/0050(ISCIII and FEDER), and Fundación Séneca (07703/GERM/07). ISG holds a fellowship from ISCIII (FI10/00535). CGM is supported by the Spanish Plan of Research & Development (BFU2010-15237).Peer reviewe

    Influencia del parámetro de personalidad Introversión-Extraversión en los efectos del alcohol sobre los tiempos de reacción

    Get PDF
    Partiendo de la teoría de Eysenck, se distinguen dos grandes dimensiones de la personalidad: -La primera abarca desde los niveles más altos de emotividad hasta los de reactividad más baja. -La segunda oscila entre los niveles más altos de introversión a los más elevados de extroversión. Ambas dimensiones siguen un continuum, habiéndose demostrado que la población se distribuye a lo largo del mismo. Por otra parte, desde un enfoque neurofisiológico, sabemos que el córtex ejerce un papel restrictivo sobre las estructuras inferiores de forma que la excitación cortical se manifestaría a través de la conducta como una disminución de la excitabilidad y un aumento de la inhibición. A la inversa, la inhibición de la actividad cortical liberaría a los centros inferiores de dicho control, manifestándose una excitabilidad aumentada y una disminución de la inhibición

    Rotationally Inelastic Collisions of CN⁻ with He: Computing Cross Sections and Rates in the Interstellar Medium

    Get PDF
    A newly calculated ab initio potential energy surface is used to compute collision-driven state-changing cross sections and rate coefficients over a range from 5 to 100 K for CN−(1Σ), the smallest anion detected in the interstellar medium, interacting with He, an abundant species in this environment. We compare our presently computed rate coefficients with those previously published for the similar and important systems CN–He, CN-H2, and CN−–H2 to illustrate the broader network of inelastic, state-changing processes for these four systems. We also discuss the size-scaling effects that occur when changing partners from He to H2. We further analyze the differences in size between collision-driven rate coefficients when going from neutral CN to its anion. All the present results are discussed in detail, to provide accurate and realistic data for chemical networks that wish to include the CN− anion in their modeling of astrochemical environments

    Molecular gas at supernova local environments unveiled by EDGE

    Full text link
    CO observations allow estimations of the gas content of molecular clouds, which trace the reservoir of cold gas fuelling star formation, as well as to determine extinction via H2_2 column density, N(H2_2). Here, we studied millimetric and optical properties at 26 supernovae (SNe) locations of different types in a sample of 23 nearby galaxies by combining molecular 12^{12}C16^{16}O (J = 1 \rightarrow 0) resolved maps from the EDGE survey and optical Integral Field Spectroscopy from the CALIFA survey. We found an even clearer separation between type II and type Ibc SNe in terms of molecular gas than what we found in the optical using Hα\alpha emission as a proxy for current SF rate, which reinforces the fact that SNe Ibc are more associated with SF-environments. While AV_V at SN locations is similar for SNe II and SNe Ibc, and higher compared to SNe Ia, N(H2_2) is significantly higher for SNe Ibc than for SNe II and SNe Ia. When compared to alternative extinction estimations directly from SN photometry and spectroscopy, we find that our SNe Ibc have also redder color excess but showed standard Na I D absorption pseudo-equivalent widths (\sim1 \AA). In some cases we find no extinction when estimated from the environment, but high amounts of extinction when measured from SN observations, which suggests that circumstellar material or dust sublimation may be playing a role. This work serves as a benchmark for future studies combining last generation millimeter and optical IFS instruments to reveal the local environmental properties of extragalactic SNe.Comment: MNRAS accepted, 17 pages, 8 Figures, 4 Table
    corecore