347 research outputs found

    Super star clusters and Supernovae in interacting LIRGs unmasked by NIR adaptive optics

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    We report on an on-going near-IR adaptive optics survey targeting interacting luminous IR galaxies. High-spatial resolution NIR data are crucial to enable interpretation of kinematic, dynamical and star formation (SF) properties of these very dusty objects. Whole progenitor nuclei in the interactions can be missed if only optical HST imaging is used. Here we specifically present the latest results regarding core-collapse supernovae found within the highly extincted nuclear regions of these galaxies. Direct detection and study of such highly obscured CCSNe is crucial for revising the optically-derived SN rates used for providing an independent measurement of the SF history of the Universe. We also present thus-far the first NIR luminosity functions of super star cluster (SSC) candidates. The LFs can then be used to constrain the formation and evolution of SSCs via constraints based on initial mass functions and cluster disruption models.Comment: 6 pages. To appear in proceedings of 'Galaxies and their Masks' (Namibia, April 2010), published by Springer, New York, eds. D.L. Block, K.C. Freeman, I. Puerar

    No AGN evidence in NGC 1614 from deep radio VLBI observations

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    We present deep dual-band 5.0- and 8.4-GHz European VLBI Network (EVN) observations of NGC 1614, a local luminous infrared galaxy with a powerful circumnuclear starburst ring, and whose nuclear engine origin is still controversial. We aim at detecting and characterizing compact radio structures both in the nuclear region and in the circumnuclear ring. We do not find any compact source in the central 200 pc region, setting a very tight 5s upper limit of 3.7 × 1036 and 5.8 × 1036 erg s-1, at 5.0 and 8.4 GHz, respectively. However, we report a clear detection at both frequencies of a compact structure in the circumnuclear ring, 190 pc to the north of the nucleus, whose luminosity and spectral index are compatible with a core-collapse supernova, giving support to the high star formation rate in the ring. Our result favours the pure starburst scenario, even for the nucleus of NGC 1614, and shows the importance of radio VLBI (very long baseline interferometry) observations when dealing with the obscured environments of dusty galaxies

    Modeling the Radio and X-ray Emission of SN 1993J and SN 2002ap

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    Modeling of radio and X-ray observations of supernovae interacting with their circumstellar media are discussed, with special application to SN 1993J and SN 2002ap. We emphasize the importance of including all relevant physical mechanisms, especially for the modeling of the radio light curves. The different conclusions for the absorption mechanism (free-free or synchrotron self-absorption), as well as departures from an ρr2\rho \propto r^{-2} CSM, as inferred by some authors, are discussed in detail. We conclude that the evidence for a variation in the mass loss rate with time is very weak. The results regarding the efficiencies of magnetic field generation and relativistic particle acceleration are summarized.Comment: 10 pages, 2 figures. Uses svmult.cls. To appear in proceedings of IAU Colloquium 192 "Supernovae (10 years of SN 1993J)", April 2003, Valencia, Spain, eds. J. M. Marcaide and K. W. Weile

    Modelo procedimental de la evaluación de las políticas públicas a través de la ludificación / Procedural model in the evaluation of public policy through gamification

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    This article proposes a procedural model designed to optimize the experience of citizens in decision making of public policies through gamification. The study assumes that gamification is motivating and contributes to increase involvement within a specific area. In this case, gamification is used to encourage citizens’ engagement in decision-making, based on three models of public policies evaluation that incorporate civic participation in three different roles: auditor, passive and active. Applying the Delphi methodology, the results of reliability and internal consistency show that experts attribute higher value to the model of active participation using gamification. In conclusion, the model designed opens a new area of knowledge within public policies evaluation, embedded in the interactivity of the media contex

    La investigación en Pediatría en España: retos y prioridades. Plataforma INVEST-AEP

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    La investigación clínica es la piedra angular para el desarrollo de la Medicina, y, en el ámbito de la Pediatría, supone un reto adicional debido a las peculiaridades que diferencian a los niños de los adultos. A pesar del enorme impacto de la salud infantil en el resto de la vida, nuestra sociedad aún no está suficientemente concienciada sobre la importancia de la investigación pediátrica, que, en general, se encuentra también muy alejada del día a día de quienes nos dedicamos a esta profesión. Desde la Asociación Española de Pediatría (AEP) se ha creado una plataforma específica de investigación —INVEST-AEP— para dar respuesta específica a los retos de la investigación en el seno de nuestra sociedad. En este artículo se retrata el escenario actual de la investigación pediátrica en España y se objetivan las metas alcanzadas en los últimos años, gracias al esfuerzo de los pediatras investigadores. Además, se realiza un análisis en profundidad sobre las barreras cotidianas que dificultan el desarrollo amplio y competitivo de la investigación pediátrica, como la falta de incentivación y ausencia de formación específica de pre y posgrado, la elevada carga asistencial o la falta de infraestructuras y financiación específicas. Definimos la misión, visión y valores de INVEST-AEP para tratar de diseñar una «hoja de ruta» para la investigación pediátrica española de los próximos años. Research is the cornerstone of medical progress. Paediatric research has its own nuances and represents an additional challenge due to the intrinsic characteristics of the paediatric population compared with adults. Despite the tremendous importance of childhood health and its impact during adulthood, society is still not convinced about the importance of conducting research in paediatrics. This also applies to paediatricians themselves, who think about research as a discipline that does not directly involve them. The Spanish Academy of Paediatrics has developed a specific research platform- INVEST-AEP- to try to help and answer the challenges associated with paediatric research in the society This article reflects the current status of paediatric research in Spain, and the goals achieved over the last few years due to the effort of paediatric researchers. In addition, a deeper analysis is provided as regards: a) the barriers that represent a hurdle for the development of broad and competitive paediatric research in our day to day work; b) the limited incentives and specific pre- and post-doctoral training; c) the high clinical burden for paediatricians or; d) the lack of specific infrastructure and dedicated funding for paediatrics. The mission, vision and values of INVEST-AEP are to develop an accessible roadmap for the development and implementation of paediatric research in Spain for the next few years

    Scattering of elastic waves by periodic arrays of spherical bodies

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    We develop a formalism for the calculation of the frequency band structure of a phononic crystal consisting of non-overlapping elastic spheres, characterized by Lam\'e coefficients which may be complex and frequency dependent, arranged periodically in a host medium with different mass density and Lam\'e coefficients. We view the crystal as a sequence of planes of spheres, parallel to and having the two dimensional periodicity of a given crystallographic plane, and obtain the complex band structure of the infinite crystal associated with this plane. The method allows one to calculate, also, the transmission, reflection, and absorption coefficients for an elastic wave (longitudinal or transverse) incident, at any angle, on a slab of the crystal of finite thickness. We demonstrate the efficiency of the method by applying it to a specific example.Comment: 19 pages, 5 figures, Phys. Rev. B (in press

    Ruxolitinib in refractory acute and chronic graft-versus-host disease : a multicenter survey study

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    Graft-versus-host disease is the main cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. First-line treatment is based on the use of high doses of corticosteroids. Unfortunately, second-line treatment for both acute and chronic graft-versus-host disease, remains a challenge. Ruxolitinib has been shown as an effective and safe treatment option for these patients. Seventy-nine patients received ruxolitinib and were evaluated in this retrospective and multicenter study. Twenty-three patients received ruxolitinib for refractory acute graft-versus-host disease after a median of 3 (range 1-5) previous lines of therapy. Overall response rate was 69.5% (16/23) which was obtained after a median of 2 weeks of treatment, and 21.7% (5/23) reached complete remission. Fifty-six patients were evaluated for refractory chronic graft-versus-host disease. The median number of previous lines of therapy was 3 (range 1-10). Overall response rate was 57.1% (32/56) with 3.5% (2/56) obtaining complete remission after a median of 4 weeks. Tapering of corticosteroids was possible in both acute (17/23, 73%) and chronic graft-versus-host disease (32/56, 57.1%) groups. Overall survival was 47% (CI: 23-67%) at 6 months for patients with aGVHD (62 vs 28% in responders vs non-responders) and 81% (CI: 63-89%) at 1 year for patients with cGVHD (83 vs 76% in responders vs non-responders). Ruxolitinib in the real life setting is an effective and safe treatment option for GVHD, with an ORR of 69.5% and 57.1% for refractory acute and chronic graft-versus-host disease, respectively, in heavily pretreated patients

    Plastid phylogenomics resolves ambiguous relationships within the orchid family and provides a solid timeframe for biogeography and macroevolution

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    Recent phylogenomic analyses based on the maternally inherited plastid organelle have enlightened evolutionary relationships between the subfamilies of Orchidaceae and most of the tribes. However, uncertainty remains within several subtribes and genera for which phylogenetic relationships have not ever been tested in a phylogenomic context. To address these knowledge-gaps, we here provide the most extensively sampled analysis of the orchid family to date, based on 78 plastid coding genes representing 264 species, 117 genera, 18 tribes and 28 subtribes. Divergence times are also provided as inferred from strict and relaxed molecular clocks and birth�death tree models. Our taxon sampling includes 51 newly sequenced plastid genomes produced by a genome skimming approach. We focus our sampling efforts on previously unplaced clades within tribes Cymbidieae and Epidendreae. Our results confirmed phylogenetic relationships in Orchidaceae as recovered in previous studies, most of which were recovered with maximum support (209 of the 262 tree branches). We provide for the first time a clear phylogenetic placement for Codonorchideae within subfamily Orchidoideae, and Podochilieae and Collabieae within subfamily Epidendroideae. We also identify relationships that have been persistently problematic across multiple studies, regardless of the different details of sampling and genomic datasets used for phylogenetic reconstructions. Our study provides an expanded, robust temporal phylogenomic framework of the Orchidaceae that paves the way for biogeographical and macroevolutionary studies

    Solitary waves for linearly coupled nonlinear Schrodinger equations with inhomogeneous coefficients

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    Motivated by the study of matter waves in Bose-Einstein condensates and coupled nonlinear optical systems, we study a system of two coupled nonlinear Schrodinger equations with inhomogeneous parameters, including a linear coupling. For that system we prove the existence of two different kinds of homoclinic solutions to the origin describing solitary waves of physical relevance. We use a Krasnoselskii fixed point theorem together with a suitable compactness criterion.Comment: 16 page
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