Chemical evolution of Seyfert galaxies

We computed the chemical evolution of Seyfert galaxies, residing in spiral bulges, based on an updated model for the Milky Way bulge with updated calculations of the Galactic potential and of the feedback from the central supermassive black hole (BH) in a spherical approximation. We followed the evolution of bulges of masses $2\times 10^{9}-10^{11}M_{\odot}$ by scaling the star-formation efficiency and the bulge scalelenght as in the inverse-wind scenario for ellipticals. We successfully reproduced the observed relation between the BH mass and that of the host bulge, and the observed peak nuclear bolometric luminosity. The observed metal overabundances are easily achieved, as well as the constancy of chemical abundances with the redshift.Comment: 2 pages, 1 figure, to appear the proceedings of IAUS245 "Formation and Evolution of Galaxy Bulges

Airborne pollens analysis in Cagliari (south Sardinia) : observations on Ailanthus altissima (Miller) Swingle,Casuarina equisetifolia J .R. & G. Foster and Schinus molle L.

In this paper the phenological and airborne pollens dispersal data of Casuarina equisetijolia J .R. & G. Foster, Ailanthus altissima (Miller) Swingle and Schinusmolle L., three exotic species widely used for street planting, are examined. The findings have enabled a detailed identification of the phenological stages and to determine the amount of airborne pollens of each species, resulting in a better understanding of their biorhythms and of their pathogenic role.peer-reviewe

Religión y política. Debates sobre laicidad como práctica política y categoría analítica en torno al movimiento feminista peruano (1990- 2010)

Este trabajo gira en torno a la pregunta ¿Cuáles son los aportes del movimiento feminista peruano a la creación y establecimiento de un pensamiento laico en el Perú durante el periodo 1990-2010? Esta pregunta responde a la poca visibilización del aporte del movimiento feminista a la construcción de la categoría laicidad. Algunas temáticas vitales para contestar esta interrogante son: la relación público/privado en relación con la educación laica y la incorporación de la raza en el quehacer político feminista. Todos estos aportes sirvieron para enriquecer la construcción de una ciudadanía desde una postura laica que integra otros campos de exclusión como el género/sexualidad, la clase y la raza

Iridoid glucosides from Pentas lanceolata (Forssk.) Deflers growing on the Island of Sardinia

The ethanolic extract of Pentas lanceolata (Forssk.) Deflers was investigated from a phytochemical point of view and in particular on the monoterpenoid glucosides content. Iridoid glucosides have a taxonomic relevance, e.g., asperuloside and its derivative are characteristic of the Rubioideae subfamily where this species is comprised. In the light of earliest phylogenetic molecular study which proposed to merge P. lanceolata in the Spermacoceae tribe, a phytochemical approach also becomes necessary for a correct classification of this species. A total of 12 compounds were identified in detail, ten of these are iridoid glucosides: asperuloside, asperulosidic acid, tudoside, E-uenfoside and Z-uenfoside previously identified in this genus; whereas, deacetyl-asperulosidic acid, ixoside, griselinoside, 6β,7β-epoxysplendoside were recognized here for the first time from P. lanceolata. Among the non-iridoidic compounds ursolic acid and d-xylose were identified

El plan no es divino...es nuestro. Reflexiones en torno al discurso de la Iglesia Católica sobre sexualidad a partir de los derechos de las personas GLBT en Perú

Dentro de los países latinoamericanos, el ejercicio pleno de la participación política se ve afectado de manera continua por diversos factores. El principal obstáculo para el desarrollo de una postura integral y completa al respecto es la presencia de discursos que eluden los múltiples niveles de interacción de cada persona, sobre todo el campo de las sexualidades. Es evidente que nuestros estados y gobiernos no han incorporado a cabalidad esta instancia dentro del sistema político, negando las posibilidades de reivindicar plenamente el derecho a vivir nuestra sexualidad

Studi sulla flora e la vegetazione di capo Carbonara (Sardegna meridionale): 1. la flora

The flora of Cape Carbonara, which is made up of 320 native species. The scarsity of the endemic component and the distinct prevalence of Terophyte is made evident. The climate characterized by its great dryness due to the scarsity of rainfall, among lowest in the Mediterraneum, is taken into consideration

Testing the universal stellar IMF on the metallicity distribution in the bulges of the Milky Way and M31

We test whether the universal initial mass function (UIMF) or the integrated galaxial IMF (IGIMF) can be employed to explain the metallicity distribution (MD) of giants in the Galactic bulge. We make use of a single-zone chemical evolution model developed for the Milky Way bulge in the context of an inside-out model for the formation of the Galaxy. We checked whether it is possible to constrain the yields above 80 M_{\sun} by forcing the UIMF and required that the resulting MD matches the observed ones. We also extended the analysis to the bulge of M31 to investigate a possible variation of the IMF among galactic bulges. Several parameters that have an impact on stellar evolution (star-formation efficiency, gas infall timescale) are varied. We show that it is not possible to satisfactorily reproduce the observed metallicity distribution in the two galactic bulges unless assuming a flatter IMF ($x \leq 1.1$) than the universal one. We conlude that it is necessary to assume a variation in the IMF among the various environments.Comment: 9 pages, 4 figures, accepted for publication in A&

Abundance Patterns in Stars in the Bulge and Galactic Center

We discuss oxygen and iron abundance patterns in K and M red-giant members of the Galactic bulge and in the young and massive M-type stars inhabiting the very center of the Milky Way. The abundance results from the different bulge studies in the literature, both in the optical and the infrared, indicate that the [O/Fe]-[Fe/H] relation in the bulge does not follow the disk relation, with [O/Fe] values falling above those of the disk. Based on these elevated values of [O/Fe] extending to large Fe abundances, it is suggested that the bulge underwent a rapid chemical enrichment with perhaps a top-heavy initial mass function. The Galactic Center stars reveal a nearly uniform and slightly elevated (relative to solar) iron abundance for a studied sample which is composed of 10 red giants and supergiants. Perhaps of more significance is the fact that the young Galactic Center M-type stars show abundance patterns that are reminiscent of those observed for the bulge population and contain enhanced abundance ratios of alpha-elements relative to either the Sun or Milky Way disk at near-solar metallicities.Comment: requires iaus.cls; to appear in Formation and Evolution of Galaxy Bulges, Proceedings IAU Symposium No. 245, 2007, M. Bureau et al. eds., in pres

The Evolution of Oxygen and Magnesium in the Bulge and Disk of the Milky Way

We show that the Galactic bulge and disk share a similar, strong, decline in [O/Mg] ratio with [Mg/H]. The similarity of the [O/Mg] trend in these two, markedly different, populations suggests a metallicity-dependent modulation of the stellar yields from massive stars, by mass loss from winds, and related to the Wolf-Rayet phenomenon, as proposed by McWilliam & Rich (2004). We have modified existing models for the chemical evolution of the Galactic bulge and the solar neighborhood with the inclusion of metallicity-dependent oxygen yields from theoretical predictions for massive stars that include mass loss by stellar winds. Our results significantly improve the agreement between predicted and observed [O/Mg] ratios in the bulge and disk above solar metallicity; however, a small zero-point normalization problem remains to be resolved. The zero-point shift indicates that either the semi-empirical yields of Francois et al. (2004) need adjustment, or that the bulge IMF is not quite as flat as found by Ballero et al. (2007); the former explanation is preferred. Our result removes a previous inconsistency between the interpretation of [O/Fe] and [Mg/Fe] ratios in the bulge, and confirms the conclusion that the bulge formed more rapidly than the disk, based on the over-abundances of elements produced by massive stars. We also provide an explanation for the long-standing difference between [Mg/Fe] and [O/Fe] trends among disk stars more metal-rich than the sun.Comment: 22 pages including 5 figures. Submitted to the Astronomical Journa