The chemical composition of carbon stars: The R-type stars

The aim of this work is to shed some light on the problem of the formation of carbon stars of R-type from a detailed study of their chemical composition. We use high-resolution and high signal-to-noise optical spectra of 23 R-type stars selected from the Hipparcos catalogue. The chemical analysis is made using spectral synthesis in LTE and state-of-the-art carbon-rich spherical model atmospheres. We derive their CNO content (including the carbon isotopic ratio), average metallicity, lithium, and light (Sr, Y, Zr) and heavy (Ba, La, Nd, Sm) s-element abundances. The observed properties of the stars (galactic distribution, kinematics, binarity, photometry and luminosity) are also discussed. Our analysis shows that late-R stars are carbon stars with identical chemical and observational characteristics than the normal (N-type) AGB carbon stars. We confirm the results of the sole previous abundance analysis of early-R stars by Dominy (1984, ApJS, 55, 27), namely: they are carbon stars with near solar metallicity showing enhanced nitrogen, low carbon isotopic ratios and no s-element enhancements. In addition, we have found that early-R stars have Li abundances larger than expected for post RGB tip giants. We also find that a significant number (aprox. 40 %) of the early-R stars in our sample are wrongly classified, being probably classical CH stars and normal K giants. In consequence, we suggest that the number of true R stars is considerably lower than previously believed. We briefly discuss the different scenarios proposed for the formation of early-R stars. The mixing of carbon during an anomalous He-flash is favoured, although no physical mechanism able to trigger that mixing has been found yet. The origin of these stars still remains a mystery.Comment: 15 pages, 8 figures, accepted for publication in Astronomy and Astrophysic

Red giants observed by CoRoT and APOGEE : the evolution of the Milky Way’s radial metallicity gradient

Using combined asteroseismic and spectroscopic observations of 418 red-giant stars close to the Galactic disc plane (6 kpc < RGal < 13 kpc, lZGall < 0.3 kpc), we measure the age dependence of the radial metallicity distribution in the Milky Way’s thin disc over cosmic time. The slope of the radial iron gradient of the young red-giant population (-0.058+- 0:008 [stat.] +-0.003 [syst.] dex/kpc) is consistent with recent Cepheid measurements. For stellar populations with ages of 1-4 Gyr the gradient is slightly steeper, at a value of -0.066 +-0.007 +- 0.002 dex/kpc, and then flattens again to reach a value of ~-0.03 dex/kpc for stars with ages between 6 and 10 Gyr. Our results are in good agreement with a state-of-the-art chemo-dynamical Milky-Way model in which the evolution of the abundance gradient and its scatter can be entirely explained by a non-varying negative metallicity gradient in the interstellar medium, together with stellar radial heating and migration. We also o er an explanation for why intermediate-age open clusters in the solar neighbourhood can be more metal-rich, and why their radial metallicity gradient seems to be much steeper than that of the youngest clusters. Already within 2 Gyr, radial mixing can bring metal-rich clusters from the innermost regions of the disc to Galactocentric radii of 5 to 8 kpc. We suggest that these outward-migrating clusters may be less prone to tidal disruption and therefore steepen the local intermediate-age cluster metallicity gradient. Our scenario also explains why the strong steepening of the local iron gradient with age is not seen in field stars. In the near future, asteroseismic data from the K2 mission will allow for improved statistics and a better coverage of the inner-disc regions, thereby providing tighter constraints on the evolution of the central parts of the Milky Way

Plan de negocios para la empresa comercial J. P. en el cantón Playas, provincia del Guayas, año 2015.

El objetivo del proyecto fue, proponer la realización de un Plan de Negocios para mejorar la comercialización de los productos para la empresa COMERCIAL J. P. en el cantón Playas, año 2015. A través de elementos conceptuales y operativos, fundamentados por un marco teórico basado en consultas bibliográficas de textos y archivos que definan con exactitud lo que es un Plan de Negocios, ayuda a definir con claridad los objetivos de una empresa o negocio describiendo métodos para alcanzarlos. En el estudio se consideraron algunos aspectos legales como el Plan del Buen Vivir, que establece reconocimiento a las pequeñas empresas para su desarrollo, se utilizaron los métodos analítico, inductivo y cualitativo con el fin de analizar las causas y efectos que incidieron en el problema, tomando como instrumento la entrevista y encuesta a los involucrados para obtener información cuantitativa sobre la problemática planteada, se aplicó la entrevista al gerente con el fin de conocer si tiene conocimiento sobre un Plan de Negocios y la aplicación del mismo, también se aplicó la encuesta a los clientes y empleados para definir la perspectiva y empatía que tienen hacia la empresa, para determinar si el cliente y la empresa necesitan del proyecto, teniendo como resultado una respuesta favorable. Se definieron las conclusiones y recomendaciones considerando que el mayor problema que surgió en la investigación fue la insatisfacción del cliente, tomando en cuenta que la mayor parte de demanda fue para la implementación de una nueva sección. Con el diseño de plan de negocios, se puntualizaron los aspectos pertinentes mejorar el nivel de comercialización de productos. Por último se desarrolla la propuesta que tiene como objetivo la implementación de una sección infantil en el local, definiendo la estructura organizacional, perfil de cada uno de ellos y recursos a utilizar, el análisis financiero que describe en números la situación de la propuesta. Con los resultados favorables los clientes, empleados y empresa cuentan con una estabilidad económica, personal y laboral, acciones que favorecen al cantón puesto que ayuda al desarrollo del mismo

From the bulge to the outer disc : StarHorse stellar parameters, distances, and extinctions for stars in APOGEE DR16 and other spectroscopic surveys

We combine high-resolution spectroscopic data from APOGEE-2 survey Data Release 16 (DR16) with broad-band photometric data from several sources as well as parallaxes from Gaia Data Release 2 (DR2). Using the Bayesian isochrone-fitting code StarHorse, we derived the distances, extinctions, and astrophysical parameters for around 388 815 APOGEE stars. We achieve typical distance uncertainties of ∼6% for APOGEE gi ants, ∼2% for APOGEE dwarfs, and extinction uncertainties of ∼0.07 mag, when all photometric information is available, and ∼0.17 mag if optical photometry is missing. StarHorse uncertainties vary with the input spectroscopic catalogue, available photometry, and parallax uncertainties. To illustrate the impact of our results, we show that thanks to Gaia DR2 and the now larger sky coverage of APOGEE-2 (including APOGEE-South), we obtain an extended map of the Galactic plane. We thereby provide an unprecedented coverage of the disc close to the Galactic mid-plane (|ZGal| < 1 kpc) from the Galactic centre out to RGal ∼ 20 kpc. The improvements in statistics as well as distance and extinction uncertainties unveil the presence of the bar in stellar density and the striking chemical duality in the innermost regions of the disc, which now clearly extend to the inner bulge. We complement this paper with distances and extinctions for stars in other public released spectroscopic surveys: 324 999 in GALAH DR2, 4 928 715 in LAMOST DR5, 408 894 in RAVE DR6, and 6095 in GES DR3

Association between Germline Single-Nucleotide Variants in ADME Genes and Major Molecular Response to Imatinib in Chronic Myeloid Leukemia Patients

Chronic myeloid leukemia; Imatinib; Single-nucleotide polymorphismsLeucèmia mieloide crònica; Imatinib; Polimorfismes d'un sol nucleòtidLeucemia mieloide crónica; Imatinib; Polimorfismos de un sólo nucleótidoImatinib is the most common first-line tyrosine kinase inhibitor (TKI) used to treat chronic-phase chronic myeloid leukemia (CP-CML). However, only a proportion of patients achieve major molecular response (MMR), so there is a need to find biological factors that aid the selection of the optimal therapeutic strategy (imatinib vs. more potent second-generation TKIs). The aim of this retrospective study was to understand the contribution of germline single-nucleotide variants (gSNVs) in the achievement of MMR with imatinib. In particular, a discovery cohort including 45 CP-CML patients was analyzed through the DMET array, which interrogates 1936 variants in 231 genes related to the absorption, distribution, metabolism and excretion (ADME) process. Variants statistically significant in the discovery cohort were then tested in an extended and independent cohort of 137 CP-CML patients. Finally, a total of 7 gSNVs (ABCG1-rs492338, ABCB11-rs496550, ABCB11-rs497692, CYP2D6-rs1135840, CYP11B1-rs7003319, MAT1A-rs4934027 and SLC22A1-rs628031) and one haplotype in the ABCB11 gene were significantly associated with the achievement of MMR with first-line imatinibtreatment. In conclusion, we identified a genetic signature of response to imatinib in CP-CML patients that could be useful in selecting those patients that may benefit from starting imatinib as first-line therapy, therefore avoiding the toxicity related to second-generation TKIs.This work was supported by Novartis Oncology (NF.5.1.2-3d.018/2014) and the Fundación Española de Hematología y Hemoterapia (FEHH-SEHH)

Co-Infections by Fusarium circinatum and Phytophthora spp. on Pinus radiata: Complex Phenotypic and Molecular Interactions

This study investigated the complex phenotypic and genetic response of Monterey pine (Pinus radiata) seedlings to co-infections by F. circinatum, the causal agent of pine pitch canker disease, and the oomycetes Phytophthora xcambivora and P. parvispora. Monterey pine seedlings were wound-inoculated with each single pathogen and with the combinations F. circinatum/P. xcambivora and F. circinatum/P. parvispora. Initially, seedlings inoculated only with F. circinatum showed less severe symptoms than seedlings co-inoculated or inoculated only with P. xcambivora or P. parvispora. However, 30 days post-inoculation (dpi), all inoculated seedlings, including those inoculated only with F. circinatum, showed severe symptoms with no significant differences among treatments. The transcriptomic profiles of three genes encoding pathogenesis-related proteins, i.e., chitinase (PR3), thaumatin-like protein (PR5), phenylalanine ammonia-lyase (PAL), and the pyruvate decarboxylase (PDC)-encoding gene were analyzed at various time intervals after inoculation. In seedlings inoculated with single pathogens, F. circinatum stimulated the up-regulation of all genes, while between the two oomycetes, only P. xcambivora induced significant up-regulations. In seedlings co-inoculated with F. circinatum and P.xcambivora or P. parvispora none of the genes showed a significant over-expression 4 dpi. In contrast, at 11 dpi, significant up-regulation was observed for PR5 in the combination F. circinatum/P.xcambivora and PDC in the combination F. circinatum/P. parvispora, thus suggesting a possible synergism of multiple infections in triggering this plant defense mechanism

The impact of sanctuary visits on children’s knowledge and attitudes toward primate welfare and conservation

Primate sanctuaries provide a solution for the increasing number of primates being taken from their home countries to support the demands of the illegal pet trade. To help end the primate trade and raise awareness about the risks this trade poses to delicate ecosystems, sanctuaries are increasingly developing conservation education programs. Education and raising awareness must be one of the primary roles of primate sanctuaries. However, there are few evaluations of the impacts of conservation education programs for school children published in scientific literature. To address this gap, we conducted an evaluation of educator-led visits of school children at Fundació Mona, a primate sanctuary located in Catalunya, Spain. Questionnaires for an experimental and control group were conducted with 3,205 school children, ages 8 to 18 from 83 different schools, to evaluate changes in their attitudes and knowledge of primate welfare and conservation. We found that Fundació Mona’s program of environmental activities had a positive impact on children, both female and male students, in terms of attitudes and knowledge of primate welfare and conservation. Although female students gave better responses regarding welfare and conservation, all children showed gains in pro-conservation responses. This study demonstrates that environmental education activities focused on children can help shape a change in knowledge and attitudes toward primate welfare and conservation. Educator-led visits of school children to primate sanctuaries such as Fundació Mona can also serve to amplify biodiversity conservation messages among children and their families. We encourage primate sanctuaries to promote empirical studies of attitudes and knowledge of primate welfare and conservation and to conduct systematical evaluations to strengthen their educational activities