1,157 research outputs found
Ca II triplet spectroscopy of small magellanic cloud red giants. II. abundances for a sample of field stars
We have obtained metallicities of ∼360 red giant stars distributed in 15 Small Magellanic Cloud (SMC) fields from near-infrared spectra covering the Ca II triplet lines using the VLT + FORS2. The errors of the derived [Fe/H] values range from 0.09 to 0.35 dex per star, with a mean of 0.17 dex. The metallicity distribution (MD) of the whole sample shows a mean value of [Fe/H] = -1.00 ± 0.02, with a dispersion of 0.32 0.01, in agreement with global mean [Fe/H] values found in previous studies. We find no evidence of a metallicity gradient in the SMC. In fact, on analyzing the MD of each field, we derived mean values of [Fe/H] = -0.99 ± 0.08 and [Fe/H] = -1.02 ± 0.07 for fields located closer and farther than 4° from the center of the galaxy, respectively. In addition, there is a clear tendency for the field stars to be more metal-poor than the corresponding cluster they surround, independent of their positions in the galaxy and of the clusters' age. We argue that this most likely stems from the field stars being somewhat older and therefore somewhat more metal-poor than most of our clusters. © 2010. The American Astronomical Society.Fil: Parisi, Maria Celeste. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Geisler, Doug. Universidad de Concepción; ChileFil: Grocholski, A. J.. University of Florida; Estados Unidos. Space Telescope Science Institute; Estados UnidosFil: Claria Olmedo, Juan Jose. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Sarajedini, A.. University of Florida; Estados Unido
Malonic acid: A potential reagent in decontamination processes for Ni-rich alloy surfaces
The ability of malonic acid as a dissolution agent toward synthetic Ni ferrite and Alloy 600 and 800 corrosion products was explored. Its performance in the dissolution kinetics of Ni ferrite powders was compared with the one of oxalic acid. Kinetic parameters were obtained and the dependency on external Fe(II) was modelled. Oxidized samples used in descaling tests were prepared by exposure of coupons of both alloys to lithiated aqueous solutions, under hydrothermal conditions and hydrogen overpressure, simulating PHWR conditions. Oxide layer morphology, the influence of exposure time to corrosive medium and LiOH concentration on its thickness were characterized. Descaling tests consisting on a two-stage method (a first oxidizing step with alkaline permanganate followed by a reducing step with oxalic or malonic acid were carried out). Results were compared to those obtained with a well known chemical cleaning formulation (APAC: Alkaline Permanganate Ammonium Citrate) used in decontamination of several reactors and loops and the competitiveness of malonic acid was demonstrated.Fil: García, D.. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Universidad Nacional de San Martín. Instituto Sabato; ArgentinaFil: Bruyre, V. I. E.. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Universidad Nacional de San Martín. Instituto Sabato; ArgentinaFil: Bordoni, R.. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; ArgentinaFil: Olmedo, A. M.. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; ArgentinaFil: Morando, Pedro Juan. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Valoración del consumo de agua y presencia de la fauna silvestre en bebederos artificiales en un entorno mediterráneo continental seco
Ca II triplet spectroscopy of Small Magellanic Cloud red giants. IV. Abundances for a large sample of field stars and comparison with the cluster sample
This paper represents a major step forward in the systematic and homogeneous study of Small Magellanic Cloud (SMC) star clusters and field stars carried out by applying the Calcium Triplet technique. We present in this study the radial velocity and metallicity of approximately 400 red giant stars in 15 SMC fields, with typical errors of about 7 km/sec and 0.16 dex respectively. We added to this information our previously determined metallicity values for 29 clusters and approximately 350 field stars using the identical techniques. Using this enlarged sample, we analize the metallicity distribution and gradient in this galaxy. We also compare the chemical properties of the clusters and of their surrounding fields. We find a number of surprising results. While the clusters, taken as a whole, show no strong evidence for a metallicity gradient, the field stars exhibit a clear negative gradient in the inner region of the SMC consistent with the recent results of Dobbie et al. (2014b). For distances to the center of the galaxy less than 4 degrees, field stars show a considerable smaller metallicity dispersion than that of the clusters. However, in the external SMC regions, clusters and field stars exhibit similar metallicity dispersions. Moreover, in the inner region of the SMC, clusters appear to be concentrated in two groups: one more metal-poor and another more metal-rich than field stars. Individually considered, neither cluster group presents a metallicity gradient. Most surprisingly, the metallicity gradient for both stellar populations (clusters and field stars) appears to reverse sign in the outer regions of the SMC. The difference between the cluster metallicity and the mean metallicity of the surrounding field stars turns out to be a strong function of the cluster metallicity. These results could be indicating different chemical evolution histories for these two stellar populations. They could also indicate variations in the chemical behavior of the SMC in its internal and external regions. Fil: Parisi, Maria Celeste. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Departamento de Astrofísica Estelar; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Concepción; ChileFil: Geisler, D.. Universidad de Concepción; ChileFil: Carraro, G.. European Southern Observatory; ChileFil: Claria Olmedo, Juan Jose. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Villanova, S.. Universidad de Concepción; ChileFil: Gramajo, Luciana Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; ArgentinaFil: Sarajedini, A.. University of Florida; Estados UnidosFil: Grocholski, A.. State University of Louisiana; Estados Unido
New old star clusters in the Small Magellanic Cloud
Using Ca triplet spectroscopy and P SF photometry performed on data taken with the “Very Large Telescope” (Chile), we derived reliable ages and metallicities of 15 Small Magellanic Cloud (SMC) star clusters. Three of them were found to be very old clusters so that the determination of their fundamental properties allows us to improve our current knowledge on the SMC chemical evolution during the earliest
epochs. Based on our new data, we further discuss the age-metallicity relation. The procedures and results included in this article will be presented in a more extensive and detailed way in Parisi et al. (2011 - in preparation).Usando espectroscopıa del Triplete del Calcio Ionizado y fotometrıa P SF realizada sobre datos tomados con el “Very Large Telescope” (Chile), derivamos edades y metalicidades confiables de 15 cumulos estelares de la Nube Menor de Magallanes (NmM). Encontramos que 3 de ellos son cumulos muy viejos, por lo que la determinacion de sus propiedades fundamentales permite mejorar nuestro actual conocimiento sobre la evolucion quımica de la NmM durante su etapa mas temprana. Basados en nuestros nuevos datos, rediscutimos la relacion edad-metalicidad en esta galaxia. Los procedimientos y resultados incluidos en este artıculo, seran presentados de manera mas extensa y detallada en Parisi et al.
(2011 - en preparacion).Fil: Parisi, M. C.. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Geisler, D.. Universidad de Concepción; ChileFil: Grocholski, A. J.. University of Florida; Estados UnidosFil: Claria Olmedo, Juan Jose. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Carraro, G.. European Southern Observatory; ChileFil: Costa, E.. Universidad de Chile; ChileFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Sarajedini, A.. University of Florida; Estados UnidosFil: Leiton, R.. Universidad de Concepción; Chil
A 3D Sensor Based on a Profilometrical Approach
An improved method which considers the use of Fourier and wavelet transform based analysis to infer and extract 3D information from an object by fringe projection on it is presented. This method requires a single image which contains a sinusoidal white light fringe pattern projected on it, and this pattern has a known spatial frequency and its information is used to avoid any discontinuities in the fringes with high frequency. Several computer simulations and experiments have been carried out to verify the analysis. The comparison between numerical simulations and experiments has proved the validity of this proposed method
Herramienta multiplataforma para generación automática de aplicaciones interactivas Ginga-NCL basado en plantillas
El presente artículo muestra una solución al desarrollo automático de aplicaciones interactivas Ginga-NCL para la Televisión Digital Terrestre, a partir de plantillas prediseñadas. Productores de televisión y gente relacionada con este medio de comunicación masivo, no conocen o simplemente no tienen las herramientas necesarias para la creación de aplicaciones interactivas, en muchos casos ni siquiera se conoce la existencia de una plataforma para el desarrollo de las mismas. Es por esta razón que se propone una metodología totalmente nueva y amigable para el usuario, la cual permita generar aplicaciones interactivas sin tener el conocimiento técnico ni las habilidades de programación que implica su creación. La reducción del tiempo en la generación de aplicaciones, disminución de capital de inversión en la preparación y adiestramiento del personal, cambios on-air en la programación interactiva del canal de televisión, son algunos de los resultados que trae consigo este sistema
Analysis of Key Features of Non-Linear Behavior Using Recurrence Plots. Case Study: Urban Pollution at Mexico City
ABSTRACT The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw data (hourly). This analysis has not been used before to extract information from large datasets for this type non-linear problem. Two different approaches have been used to tackle this problem. The first approach is to show results according to monitoring network. The second approach is to show the results by particle type. This analysis shows the feasibility of using Recurrence Analysis for pollution monitoring and control
Revista de Vertebrados de la Estación Biológica de Doñana
Relación longitud-peso y condición del Barbo de Sclater (Barbus barbus sclateri G.), en el río Guadiato, Córdoba, España.Estudio biométrico y biológico de la tortuga mora (Testudo graeca) en la Reserva Biológica de Doñana, HuelvaEtograma del lagarto de Tenerife, Gallotia galloti galloti (Sauria-LacertidaeOrganización temporal en las comunidadesde avesAlimentación y relaciones tróficas entre los paseriformes en paso otoñal por una localidad de Andalucía centralVariación anual de régimen alimenticio y densidad de población de dos estrigiformes:sus causaslas Adeidas en la cuenca del Duero.Niveles de contaminantes organoclorados y metales pesados en huevos de aves de las Marismas del Guadalquivir, 1975Alimentación primaveral de la garcilla bueyera.la reproducción de un ave parásita: el tordomirlo (Molothrus bonariensis) en los llanos de Apure (Venezuela)Estructuras de sexos y edades en una poblaciónde conejos (Oryctolagus cunicuLus l.) de Andalucía OccidentaParámetros de gregarismo del gamo (Dama dama) en el Coto de Doñana.Primeros datos sobre la distribución de Cobitis calderoni Bacescu, 1961 (pisces, cobitidae) en la Península IbéricaSobre la existencia de Telestes soufia Risso, 1826 y Leuciscus leuciscus L. 1758 en España.La distrtibución de Hemidactylus turciscus en la provincia de Córdoba.Predación de Vipera latastei sobre Mustela nivalis.Sobre las poblaciones de Podarcis en el macizo del GuadarramaDatos sobre la reproducción de Lacerta vivipara en la cordillera CantábricaCasos de melanismo en Natrix natrix y Malpolon monspessulanusMedidas máximas para Coluber hippocrepis LUna nueva población de Lacerta sicula rafinesque para el norte de España.Captura de la barnacla carinegra, Branta bernicla en la costa mediterránea Europea.Datos sobre la dieta frugívora del mirlo (Turdus merula) en dos localidades del sur de EspañaLa ocupación de nidos de Hirundo daurica.La invasión de Hirunda daurica Temm. en la Península IbéricaHíbridos de anátidas en las marismas del GuadalquiviDatos sobre la reproducción de Alouatta seniculus en los Llanos de VenezuelaPeer reviewe
Combination lurbinectedin and doxorubicin versus physician's choice of chemotherapy in patients with relapsed small-cell lung cancer (ATLANTIS): a multicentre, randomised, open-label, phase 3 trial
Background Lurbinectedin is a synthetic marine-derived anticancer agent that acts as a selective inhibitor of oncogenic transcription. Lurbinectedin monotherapy (3middot2 mg/m2 every 3 weeks) received accelerated approval from the US Food and Drug Administration on the basis of efficacy in patients with small-cell lung cancer (SCLC) who relapsed after first-line platinum-based chemotherapy. The ATLANTIS trial assessed the efficacy and safety of combination lurbinectedin and the anthracycline doxorubicin as second-line treatment for SCLC.Methods In this phase 3, open-label, randomised study, adult patients aged 18 years or older with SCLC who relapsed after platinum-based chemotherapy were recruited from 135 hospitals across North America, South America, Europe, and the Middle East. Patients were randomly assigned (1:1) centrally by dynamic allocation to intravenous lurbinectedin 2middot0 mg/m2 plus doxorubicin 40middot0 mg/m2 administered on day 1 of 21-day cycles or physician's choice of control therapy (intravenous topotecan 1middot5 mg/m2 on days 1-5 of 21-day cycles; or intravenous cyclophosphamide 1000 mg/m2 , doxorubicin 45middot0 mg/m2 , and vincristine 2middot0 mg on day 1 of 21-day cycles [CAV]) administered until disease progression or unacceptable toxicity. Primary granulocyte-colony stimulating factor prophylaxis was mandatory in both treatment groups. Neither patients nor clinicians were masked to treatment allocation, but the independent review committee, which assessed outcomes, was masked to patients' treatment allocation. The primary endpoint was overall survival in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02566993, and with EudraCT, 2015-001641-89, and is complete.Findings Between Aug 30, 2016, and Aug 20, 2018, 613 patients were randomly assigned to lurbinectedin plus doxorubicin (n=307) or control (topotecan, n=127; CAV, n=179) and comprised the intention-to-treat population; safety endpoints were assessed in patients who had received any partial or complete study treatment infusions (lurbinectedin plus doxorubicin, n=303; control, n=289). After a median follow-up of 24middot1 months (95% CI 21middot7-26middot3), 303 patients in the lurbinectedin plus doxorubicin group and 289 patients in the control group had discontinued study treatment; progressive disease was the most common reason for discontinuation (213 [70%] patients in the lurbinectedin plus doxorubicin group vs 152 [53%] in the control group). Median overall survival was 8middot6 months (95% CI 7middot1-9middot4) in the lurbinectedin plus doxorubicin group versus 7middot6 months (6middot6-8middot2) in the control group (stratified log-rank p=0middot90; hazard ratio 0middot97 [95% CI 0middot82-1middot15], p=0middot70). 12 patients died because of treatment-related adverse events: two (<1%) of 303 in the lurbinectedin plus doxorubicin group and ten (3%) of 289 in the control group. 296 (98%) of 303 patients in the lurbinectedin plus doxorubicin group had treatment-emergent adverse events compared with 284 (98%) of 289 patients in the control group; treatment-related adverse events occurred in 268 (88%) patients in the lurbinectedin plus doxorubicin group and 266 (92%) patients in the control group.Grade 3 or worse haematological adverse events were less frequent in the lurbinectedin plus doxorubicin group than the control group (anaemia, 57 [19%] of 302 patients in the lurbinectedin plus doxorubicin group vs 110 [38%] of 288 in the control group; neutropenia, 112 [37%] vs 200 [69%]; thrombocytopenia, 42 [14%] vs 90 [31%]). The frequency of treatment-related adverse events leading to treatment discontinuation was lower in the lurbinectedin plus doxorubicin group than in the control group (26 [9%] of 303 patients in the lurbinectedin plus doxorubicin group vs 47 [16%] of 289 in the control group).Interpretation Combination therapy with lurbinectedin plus doxorubicin did not improve overall survival versus control in patients with relapsed SCLC. However, lurbinectedin plus doxorubicin showed a favourable haematological safety profile compared with control.Pathogenesis and treatment of chronic pulmonary disease
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