2,130 research outputs found

    Pedigree analysis of 220 almond genotypes reveals two world mainstream breeding lines based on only three different cultivars

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    Loss of genetic variability is an increasing challenge in tree breeding programs due to the repeated use of a reduced number of founder genotypes. However, in almond, little is known about the genetic variability in current breeding stocks, although several cases of inbreeding depression have been reported. To gain insights into the genetic structure in modern breeding programs worldwide, marker-verified pedigree data of 220 almond cultivars and breeding selections were analyzed. Inbreeding coefficients, pairwise relatedness, and genetic contribution were calculated for these genotypes. The results reveal two mainstream breeding lines based on three cultivars: “Tuono”, “Cristomorto”, and “Nonpareil”. Descendants from “Tuono” or “Cristomorto” number 76 (sharing 34 descendants), while “Nonpareil” has 71 descendants. The mean inbreeding coefficient of the analyzed genotypes was 0.041, with 14 genotypes presenting a high inbreeding coefficient, over 0.250. Breeding programs from France, the USA, and Spain showed inbreeding coefficients of 0.075, 0.070, and 0.037, respectively. According to their genetic contribution, modern cultivars from Israel, France, the USA, Spain, and Australia trace back to a maximum of six main founding genotypes. Among the group of 65 genotypes carrying the Sf allele for self-compatibility, the mean relatedness coefficient was 0.125, with “Tuono” as the main founding genotype (24.7% of total genetic contribution). The results broaden our understanding about the tendencies followed in almond breeding over the last 50 years and will have a large impact into breeding decision-making process worldwide. Increasing current genetic variability is required in almond breeding programs to assure genetic gain and continuing breeding progress

    [Determinants of the use of different healthcare levels in the General System of Social Security in Health in Colombia and the Unified Health System in Brazil].

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    OBJECTIVE: To compare the use of different healthcare levels, and its determinants, in two different health systems, the General System of Social Security in Health (GSSSH) and the Unified Health System (UHS) in municipalities in Colombia and Brazil. METHODS: A cross-sectional study was carried out, based on a population survey in two municipalities in Colombia (n=2163) and two in Brazil (n=2155). Outcome variables consisted of the use of primary care services, outpatient secondary care services, and emergency care in the previous 3 months. Explanatory variables were need and predisposing and enabling factors. Bivariate and multivariate logistic regression analyses were performed by healthcare level and country. RESULTS: The determinants of use differed by healthcare level and country: having a chronic disease was associated with a greater use of primary and outpatient secondary care in Colombia, and was also associated with the use of emergency care in Brazil. In Colombia, persons enrolled in the contributory scheme more frequently used the services of the GSSSH than persons enrolled with subsidized contributions in primary and outpatient secondary care and more than persons without insurance in any healthcare level. In Brazil, the low-income population and those without private insurance more frequently used the UHS at any level. In both countries, the use of primary care was increased when persons knew the healthcare center to which they were assigned and if they had a regular source of care. Knowledge of the referral hospital increased the use of outpatient secondary care and emergency care. CONCLUSIONS: In both countries, the influence of the determinants of use differed according to the level of care used, emphasizing the need to analyze healthcare use by disaggregating it by level of care

    Estructuración e integración de la información del planeamiento urbanístico en modelo de datos SIG y publicación en servicio estándar OGC

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    Consiste en la estructuración en bases SIG del planeamiento urbanístico municipal de Ullastrell para la publicación en Internet a través del servidor de mapas del Consell Comarcal del Vallès Occidental. Como resultados principales, cabe destacar: Una geobase de datos con los datos del municipio de Ullastrell con capacidad para integrar la información del resto de municipios de la comarca. Un geoservicio (WMS) que permitirá la visualización y consulta del planeamiento urbanístico y su normativa con la progresiva integración del resto de municipios que forman parte de la comarca. Definición de un protocolo que servirá como guía a los ayuntamientos con tal de estructurar la información espacial del planeamiento urbanístico y facilitar su transformación a formato de datos espaciales SIG.Consisteix en l'estucturació en bases SIG del planejament urbanístic municipal d'Ullastrell per a la publicació en Internet a través del visor de mapes del Consell Comarcal del Vallès Occidental. Com resultats principals, cal destacar: Una geobase de dades amb les dades del municipi d'Ullastrell amb capacitat per integrar la informació de la resta de municipis de la comarca. Un geoservei (WMS) que permetrà la visualització i consulta del planejament urbanístic i la seva normativa amb la progessiva integració de la resta de municipis que en formen part de la comarca. Definició d'un protocol que servirà com guia als ajuntaments per tal d'estructurar la informació espacial del planejament urbanístic i facilititar la seva transformació a formats de dades espacials SIG

    Chemical Abundances and Ionizing Clusters of HII Regions in the LINER Galaxy NGC 4258

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    We present long-slit observations in the optical and near infrared of eight HII regions in the spiral galaxy NGC 4258. Six of the observed regions are located in the SE inner spiral arms and the other two are isolated in the northern outer arms. A detailed analysis of the physical conditions of the gas has been performed. For two of the regions, an electron temperature has been derived from the [SIII] 6312 A line. For the rest, an empirical calibration based on the red and near infrared sulphur lines has been used. The oxygen abundances derived by both methods are found to be significantly lower (by a factor of two) than previously derived by using empirical calibrations based on the optical oxygen lines. In the brightest region, 74C, the observation of a prominent feature due to Wolf-Rayet stars provides an excellent constraint over some properties of the ionizing clusters. In the light of the current evolutionary synthesis models, no consistent solution is found to explain at the same time both the WR feature characteristics and the emission line spectrum of this region. In principle, the presence of WR stars could lead to large temperature fluctuations and also to a hardening of the ionizing radiation. None of these effects are found in region 74C for which the electron temperatures found from the [SIII] 6312A and the Paschen discontinuity at 8200A are equal within the errors and the effective temperature of the ionizing radiation is estimated at around 35,300K. Both more observations of confirmed high metallicity regions and a finer metallicity grid for the evolutionary synthesis models are needed in order to understand the ionizing populations of HII regions.Comment: 16 pages, 16 figures. To appear in MNRA

    A comparative analysis of empirical calibrators for nebular metallicity

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    We present a new analysis of the main empirical calibrators of oxygen abundance for ionised gas nebulae. With that aim we have compiled an extensive sample of objects with emission line data including the near IR [SIII] lines and the weak auroral lines which allow for the determination of the gas electron temperature. For all the objects the oxygen abundances have been derived in a homogeneus way, using the most recent sets of atomic coefficients and taking into the account the effect of particle density on the temperature of O+^+. The residuals between directly and empirically-derived abundances as a function of abundance have been studied. A grid of photo-ionisation models, covering the range of physical properties of the gas, has been used to explain the origin of the uncertainties affecting each abundance calibrator. The range of validity for each abundance parameter has been identified and its average uncertainty has been quantified.Comment: 16 pages, 26 figures, accepted for publication in MNRA

    The MEGARA view of outflows in LINERs

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    Outflows are believed to be ubiquitous in all AGNs, although their presence in low luminosity AGNs, in particular, for LINERs, has only started to be explored. Their properties (geometry, mass and energetics) are still far from being properly characterised. We use integral field spectroscopic data from the MEGARA instrument, at GTC, to analyse a small sample of nine LINERs, candidates of hosting ionised gas outflows. We aim to study the main emission lines in the optical to identify their properties and physical origin. We obtained data cubes at the lowest (R\sim6000) and highest (R\sim20000) spectral resolution of MEGARA. We modelled and subtracted the stellar continuum to obtain the ionised gas contribution, and then fitted the emission lines to extract their kinematics (velocity and velocity dispersion). We identified outflows as a secondary component in the emission lines. The primary component of the emission lines was typically associated to gas in the galactic disc. For some objects, there is an enhanced-σ\sigma region co-spatial with the secondary component. We associated it to turbulent gas produced due to the interaction with the outflows. We find signatures of outflows in six LINERs, with mass outflow rates ranging from 0.004 to 0.4 Msun_{sun}yr1^{-1} and energy rates from \sim1038^{38} to \sim1040^{40} erg s1^{-1}. Their mean electronic density is 600cm3^{-3}, extending to distances of \sim400 pc at an (absolute) velocity of \sim340 km s1^{-1} (on average). They tend to be compact and unresolved, although for some sources they are extended with a bubble-like morphology. Our results confirm the existence of outflows in the best LINER candidates identified using previous long-slit spectroscopic and imaging data. These outflows do not follow the scaling relations obtained for more luminous AGNs. For some objects we discuss jets as the main drivers of the outflowsComment: 31 pages, 15 figures. Accepted for publication in Astronomy & Astrophysic

    MEGARA-GTC stellar spectral library: I

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    MEGARA (Multi Espectrografo en GTC de Alta Resolucion para Astronomia) is an optical (3650-9750 Å), fibre-fed, medium-high spectral resolution (R = 6000, 12 000 and 20 000) instrument for the Gran Telescopio CANARIAS (GTC) 10.4-m telescope, commissioned in the summer of 2017, and currently in operation. The scientific exploitation of MEGARA requires a stellar spectra library to interpret galaxy data and to estimate the contribution of the stellar populations. In this paper, we introduce the MEGARA-GTC spectral library, detailing the rationale behind the building of this catalogue. We present the spectra of 97 stars (21 individual stars and 56 members of the globular cluster M15, which are both subsamples taken during the commissioning runs, and 20 stars from our ongoing GTC Open-Time programme). The spectra have R = 20 000 in the HR-R and HR-I set-ups, centred at 6563 and 8633 Å, respectively. We describe the procedures to reduce and analyse the data. Then, we determine the best-fitting theoretical models to each spectrum through a χ^(2) minimization technique, to derive the stellar physical parameters, and we discuss the results. We have also measured some absorption lines and indices. Finally, we introduce our project to complete the library and the data base in order to make the spectra available to the community

    The detection of stellar velocity dispersion drops in the central regions of five isolated Seyfert spirals

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    We analyze the kinematics of the central regions of five isolated Seyfert spiral galaxies from the DEGAS sample (four with new data presented in this paper, IC184, UGC3223, NGC2639, NGC6814, and NGC6951 from our previous data), by using long slit spectroscopy in the CaII triplet range (at ~ 8600 A) obtained with a 4m-class telescope. A drop of the velocity dispersions in the innermost 1-3 arcsec is observed in four of them, and hinted in the remaining galaxy (NGC6814). The available HST images for our sample together with another nine galaxies with reported velocity dispersion drops, are also used to investigate the presence of morphological inner structures at the scales of the kinematical drops. Evidence for disk-like shapes is found in 12 out of the 14 cases. The only exceptions are NGC6814 and NGC6951. Existing N-body simulations including stars, gas and star formation predict that such a drop is most probably due to a young stellar population born from dynamically cold gas accreted in a circumnuclear disk formed during an episode of central gas accretion driven by a bar. The equivalent widths of the Calcium triplet lines for our 5 galaxies have been measured. Even if the profiles could be formally consistent with constant EW(CaT) values, they seem to indicate the presence of a local maximum in the regions corresponding spatially to the drops; if confirmed, this would imply the presence of a different stellar population, whose properties could help constraining the models.Comment: A&A accepted for publicatio

    Pedigree analysis of 220 almond genotypes reveals two world mainstream breeding lines based on only three different cultivars

    Get PDF
    Loss of genetic variability is an increasing challenge in tree breeding programs due to the repeated use of a reduced number of founder genotypes. However, in almond, little is known about the genetic variability in current breeding stocks, although several cases of inbreeding depression have been reported. To gain insights into the genetic structure in modern breeding programs worldwide, marker-verified pedigree data of 220 almond cultivars and breeding selections were analyzed. Inbreeding coefficients, pairwise relatedness, and genetic contribution were calculated for these genotypes. The results reveal two mainstream breeding lines based on three cultivars: “Tuono”, “Cristomorto”, and “Nonpareil”. Descendants from “Tuono” or “Cristomorto” number 76 (sharing 34 descendants), while “Nonpareil” has 71 descendants. The mean inbreeding coefficient of the analyzed genotypes was 0.041, with 14 genotypes presenting a high inbreeding coefficient, over 0.250. Breeding programs from France, the USA, and Spain showed inbreeding coefficients of 0.075, 0.070, and 0.037, respectively. According to their genetic contribution, modern cultivars from Israel, France, the USA, Spain, and Australia trace back to a maximum of six main founding genotypes. Among the group of 65 genotypes carrying the Sf allele for self-compatibility, the mean relatedness coefficient was 0.125, with “Tuono” as the main founding genotype (24.7% of total genetic contribution). The results broaden our understanding about the tendencies followed in almond breeding over the last 50 years and will have a large impact into breeding decision-making process worldwide. Increasing current genetic variability is required in almond breeding programs to assure genetic gain and continuing breeding progress.info:eu-repo/semantics/publishedVersio

    Observation of the Crab Nebula with the HAWC Gamma-Ray Observatory

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    The Crab Nebula is the brightest TeV gamma-ray source in the sky and has been used for the past 25 years as a reference source in TeV astronomy, for calibration and verification of new TeV instruments. The High Altitude Water Cherenkov Observatory (HAWC), completed in early 2015, has been used to observe the Crab Nebula at high significance across nearly the full spectrum of energies to which HAWC is sensitive. HAWC is unique for its wide field-of-view, nearly 2 sr at any instant, and its high-energy reach, up to 100 TeV. HAWC's sensitivity improves with the gamma-ray energy. Above \sim1 TeV the sensitivity is driven by the best background rejection and angular resolution ever achieved for a wide-field ground array. We present a time-integrated analysis of the Crab using 507 live days of HAWC data from 2014 November to 2016 June. The spectrum of the Crab is fit to a function of the form ϕ(E)=ϕ0(E/E0)αβln(E/E0)\phi(E) = \phi_0 (E/E_{0})^{-\alpha -\beta\cdot{\rm{ln}}(E/E_{0})}. The data is well-fit with values of α=2.63±0.03\alpha=2.63\pm0.03, β=0.15±0.03\beta=0.15\pm0.03, and log10(ϕ0 cm2 s TeV)=12.60±0.02_{10}(\phi_0~{\rm{cm}^2}~{\rm{s}}~{\rm{TeV}})=-12.60\pm0.02 when E0E_{0} is fixed at 7 TeV and the fit applies between 1 and 37 TeV. Study of the systematic errors in this HAWC measurement is discussed and estimated to be ±\pm50\% in the photon flux between 1 and 37 TeV. Confirmation of the Crab flux serves to establish the HAWC instrument's sensitivity for surveys of the sky. The HAWC survey will exceed sensitivity of current-generation observatories and open a new view of 2/3 of the sky above 10 TeV.Comment: Submitted 2017/01/06 to the Astrophysical Journa
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