Integral field spectroscopy of nitrogen overabundant blue compact dwarf galaxies

We study the spatial distribution of the physical properties and of oxygen and nitrogen abundances in three Blue Compact Dwarf Galaxiess (HS 0128+2832, HS 0837+4717 and Mrk 930) with a reported excess of N/O in order to investigate the nature of this excess and, particularly, if it is associated with Wolf-Rayet (WR) stars We have observed these BCDs by using PMAS integral field spectroscopy in the optical spectral range (3700 - 6900 {\AA}), mapping their physical-chemical properties, using both the direct method and appropriate strong-line methods. We make a statistical analysis of the resulting distributions and we compare them with the integrated properties of the galaxies. Our results indicate that outer parts of the three galaxies are placed on the "AGN-zone" of the [NII]/H{\alpha} vs. [OIII]/H{\beta} diagnostic diagram most likely due to a high N/O combined with the excitation structure in these regions. From the statistical analysis, it is assumed that a certain property can be considered as spatially homogeneous (or uniform) if a normal gaussian function fits its distribution in several regions of the galaxy. Moreover, a disagreement between the integrated properties and the mean values of the distribution usually appears when a gaussian does not fit the corresponding distribution. We find that for Mrk 930, the uniformity is found for all parameters, except for electron density and reddening. The rotation curve together with the H{\alpha} map and UV images, reveal a perturbed morphology and possible interacting processes. The N/O is found to be constant in the three studied objects at spatial scales of the order of several kpc so we conclude that the number of WR stars estimated from spectroscopy is not sufficient to pollute the ISM and to produce the observed N/O excess in these objectsComment: 17 pages, 14 figures, accepted for publication in Astronomy & Astrophysic

A Spectroscopic Study of the Near-IR [SIII] Lines in a Sample of HII Galaxies: chemical abundances

A detailed spectroscopic study, from lambda 3700 A to 1 um, was performed for a sample of 34 HII galaxies in order to derive fundamental parameters for their HII regions and ionizing sources, as well as gaseous metal abundances. All the spectra included the nebular [SIII]9069,9532 A lines, given their importance in the derivation of the S/H abundance and relevant ionization diagnostics. A systematic method was followed to correct the near-IR [SIII] line fluxes for the effects of the atmospheric transmission.A comparative analysis of the predictions of the empirical abundance indicators R23 and S23 has been performed. The relative hardness of their ionizing sources was studied using the eta parameter, and exploring the role played by metallicity. For 22 galaxies of the sample a direct value of te[SIII] was derived, along with their ionic and total S/H abundances. Their ionic and total O/H abundances were derived using direct determinations of te[OIII].For the rest of the objects, the total S/H abundance was derived using S23. The abundance range covered by our sample goes from 1/20 solar up to solar metallicity. The mean S/O ratio derived is log (S/O)=-1.68+/-0.20 dex, 1 sigma below the solar S/O value. The S/O abundance ratio shows no significant trend with O/H over the range of abundance covered in this work, in agreement with previous findings.There is a trend for HII galaxies with lower gaseous metallicity to present harder ionizing spectra. We compared the distribution of the ionic ratios O+/O++ vs. S+/S++ derived for our sample with the predictions of a grid of photoionization models performed for different stellar effective temperatures. This analysis indicates that a large fraction of galaxies in our sample seem to be ionized by extremely hard spectra.Comment: 12 pages, 8 figures, accepted for publication in the A&A, minor gramatical corrections include

Revisión de las ideas morales y políticas de Concepción Arenal

Tesis de la Universidad Complutense de Madrid, Facultad de Derecho, Departamento de Filosofía del Derecho, Moral y Política I, leída el 13-09-2002El objetivo de esta tesis ha sido el de reunir y revisar las distintas facetas que el pensamiento de Concepción Arenal engloba. Los cinco capítulos en los que se divide esta investigación (Estudio biobibliográfico de su figura; Humanismo versus C. Arenal; C. Arenal: baluarte de la dignidad de la mujere y del ser humano; C. Arenal: educación humanitaria; Justicia, Moral y Derecho: tres pilares básicos en el pensamiento arenaliano) se propusieron aunar la síntesis de sus ideas encuadradas en su época, a la vez que incluir el germen de algunas de las mismas con las que sería una adelantada a su tiempo en multitud de ocasiones. Esto, junto a posteriores tratamientos y estudios doctrinales y mis aportaciones constituirá el tronco de su contenido y finalidad. La dignidad, junto a la libertad y a la solidaridad por ella preconizada, constituirá una continuidad en los valores resaltados y recogidos en nuestras declaraciones de derechos actuales. "Su feminismo" representará una de las corrientes más actuales del pensamiento feminista abierto y universal, en el que se incluiría a cualquier persona que estuviera dispuesta a luchar contra la opresión. La capacidad de elección mediante la educación y la cultura se presentaban, así, como claves para la liberación de la mujer, del ser humano integral. Su desafío quiso basarse en la necesidad de interiorizar, de hacer llegar al espírituo de los pueblos un deseo de saber a base de Moral y de Justicia. Este anhelo conformaba su esperanza en la cultura y en la solidaridad, las mismas que hoy siguen cobrando actualidad frente a algunas carencias todavía no superadas de nuestras sociedades en el nuevo siglo. Su pensamiento jurídico planteaba una de las cuestiones más discutidas en nuestra doctrina jurídica-filosófica: la relación-conexión derecho-moral. Exaltadora de la justicia, de la que partía la idea del derecho, y del amor como guía del progreso la harán adentrarse en la reforma penitenciaria como "problema de todos". Recogiendo a la vez las más modernas ideas dirigidas a la resocialización. La humanización de nuestras relaciones, del derecho -sin caer en falsas y vacías utopías o sentimentalismos-, la olvidada o sobrentendia humanización del hombre en un proyecto común de moderno desarrollo social civilizado, de una humanidad como garantía de libertad y pacífica convivencia, son las principales e intemporales características que nos aporta la revisión de sus ideasDepto. de Derecho Internacional, Eclesiástico y Filosofía del DerechoFac. de DerechoTRUEpu

Theoretical investigation of the eight low-lying electronic states of the cis- and trans-nitric oxide dimers and its isomerization using multiconfigurational second-order perturbation theory (CASPT2)

In this work we have carried out ab initio electronic structure calculations, CASSCF/CASPT2 and CASSCF/MRCI-SD+Q with several Pople's and correlation-consistent Dunning's basis sets, of the planar cis- and trans-NO dimers for the lowest eight electronic (singlet and triplet) states. The geometry, frequencies, dipole moment, binding energy, and vertical excitation energies are predicted with an accuracy close to or even better than the best reported ab initio previous results for some of these properties, and in very good agreement with the available experimental data. CASPT2 optimized geometries show the existence of at least four shallow NO-dimers (i.e., two cis-(NO)2 (1A1 and 3B2) and two trans-(NO)2 (1Ag and 3Au)), although CASSCF optimization with CASPT2 pointwise calculations indicate the existence of other less stable dimers, on the excited states. Vertical excitation energies were calculated for these four dimers. For the cis-NO dimer, the ordering and the energy spacings between the excited states (i.e., 1A1, 3B2, 1B2, 2nd 1A1, 1A2, 3A2, 3B1, 2nd 3B1) are very similar to those found in a recent MRCI-SD study. The singlet cis-NO dimer (1A1) is the most stable one in almost quantitative accord with the experimental data, and in disagreement with previous density functional theory studies. A nonplanar transition state for the singlet trans ↔ cis isomerization has also been fully characterized. This leads to an almost negligible energy barrier which would originate a rapid isomerization to the most stable cis-NO dimer at low temperatures, in accord with the experimental difficulties to measure the properties of the trans-NO dimer. Not only are basis set superposition error corrections necessary to evaluate accurately the binding energies, but also to determine the NN distance of these symmetrical dimers. Some problems regarding the symmetry of the wave function were found for the symmetrical NO dimers and for the NO+NO asymptote, and several approximate solutions were proposed

Microbial weathering of Fe-rich phyllosilicates and formation of pyrite in the dolomite precipitating environment of a Miocene lacustrine system

Sedimentary sequences composed of selenite gypsum, mudstone, and dolomite microbialites cropping out in the eastern part of the Madrid Basin were deposited in a mudflat – saline-lake system during the Miocene. In some dolomite beds enriched in detrital grains, dolomite crystals occur intergrown with framboidal pyrite clusters that in many cases are arranged along the associated phyllosilicate cleavages, which accounts for the mineral disaggregation, and eventually for the mineral replacement. Highresolution FE-SEM investigations across the interface between the pyrite and the phyllosilicate show that a single phyllosilicate is replaced by iron sulphides in different microsites, with retention of some aspects of the parent structure. Pyrite formed in the sediment as texturally complex framboids, coexisting with amorphous to poorly crystalline iron-rich sulphide phases, and include carbonaceous filaments with biogenic isotopic signatures (δ 13 C = -22.95 ‰). Microprobe analytical data indicate the weathered phyllosilicates to be significantly depleted in Fe relative to Si and Al. The selective release of Fe has not involved the mineral transformation to secondary phyllosilicates, which suggests a preferential microbial colonization of the Fe-bearing minerals rather than a thermodynamically driven degradation of those minerals. Depleted δ 34 S values in pyrite further suggest that sulphate microbial reduction to sulphide was active within the sediment during the alteration of the silicates. This paper gives new insight into the microbial weathering of phyllosilicates and the subsequent formation of pyrite through a sequence of intermediate products enriched in iron. These processes were coeval with the microbially-mediated precipitation of dolomite, which further reinforces the role of the microbes in the formation of the sulphides

Ab initio 1A' ground potential energy surface and transition state theory kinetics study of the O(1D) + N2O → 2NO, N2 +O2(a1Δg) reactions

An ab initio study of the 1A' ground potential energy surface (PES) of the O(1D) + N2O(X1+) system has been performed at the CASPT2//CASSCF (complete active space second-order perturbation theory//complete active space self-consistent field) level with Pople basis sets. The two reactions leading to 2 NO(X2) [reaction (1)] and N2(X1g+) + O2(a1∆g) [reaction (2)] products have been investigated. In both reactions a trans-approach of the attacking oxygen to the N2O moiety is found to be preferred, more markedly in reaction (1). For this reaction also a cis-path is feasible and is possibly connected with the trans -path by a transition state placed below reactants. A thorough characterization of the entrance zone has been performed to allow for subsequent kinetics calculations. Fixed angle and minimum energy paths have been constructed and transition state geometries have been refined at the CASPT2 level, thus obtaining approximate structures and frequencies for the latter. From these calculations it can be inferred that both reactions proceed without an energy barrier. Rate constant calculations in the 100-1000 K temperature range based on CASPT2 structures and using the transition state theory yield values in good agreement with experiment for the two reactions, especially when a proper scaling of the energy barriers is performed. Also, for comparative purposes quasiclassical trajectory calculations were performed on reaction (1) in the same temperature range, using a previous pseudotriatomic analytical potential energy surface, obtaining good agreement with experiment

A catabogne on tite benthic marine flora of ida Tina Menor and Pechon’s coast (Cantabria, Spain)

FERNÁNDEZ-MONTERO, L.; PÉREZ-RUZAFA, 1. M.; CUBERO, 1. & GALLARDO, T., 1997. Catálogo de la flora bentónica marina de la Ría lina Menor y costa de Pechón (Cantabria)- Bot Cotnplutensis 22: 83-100. Los muestreos efectuados en la Ría lina Menor y costa de Peehón durante el otoño e invmerno de 1995 y la primavera, verano y otoño de 1996 han dado como resultado un catálogo de 202 especies (4 Cyanophyceae, 127 Rhodophyceae, 39 Phaeopltvceae. 1 Chlorophyceae, 18 Ulvophyceae, 6 Cladophorophyceae, 6 Bryopsidophyceae, y 1 Magnoliophyta). El número total de nuevas citas para las costas de Cantabria es de 87.FERNÁNDEZ-MONTERO, L.; PÉREZ-RUZAFA, 1. M.~ CUBERO, 1. & GAlLARDO, 1., 1997. A catalogue on the benthic marine flora of Ría Tina Menor and Pechón's eoast (Cantabria, Spain). Rbi. Complutensis 22: 83-100. Samples, done in Ría Tina Menor and Pechón's coast (Cantabria, Spain) during the aututu aud winterot 1995 andthe spring, summer and autum of 1996, sho'w a 11sf of 202 species (4 Cyanophyceae, 127 Rhodophyceae, 39 Phaeophyceae, 1 Chlorophyceae, ¡8 UIvophyceae, 6 Cladophorophyceae, 6 Brvopsidophyceac, and 1 Magnolioplmvta). Ihe number ol new records for Cantabria is 87

Calcificaciones heterotópicas en cirugía protésica de cadera: Prótesis bicénctricas vs híbridas

Realizamos el seguimiento clínico y radiológico de 202 pacientes a los que se implantó una Prótesis Total de Cadera cementada (PTC). Analizamos la presencia de calcificaciones heterotópicas (CH) y su graduación, estudiando separadamente prótesis híbridas y bicéntricas. Valoramos los factores de riesgo relacionados con la aparición de CH, tamaño de implantes, alineación final, lado intervenido y relación con la presencia de complicaciones locales y sistemáticas. La prevalencia de CH fue de 35.5% (grado I, 19%; grado II, 10%; grado III, 5% y grado IV 1,5%); 9,9 % sintomáticas. Una mayor proporción de CH fue observada en varones (p=0,005); vástagos de mayor tamaño (p=0,001). No existen diferencias significativas (p=0,059) entre pacientes con prótesis híbridas frente a aquellos con prótesis bicéntricas. La valoración de Harris mostró diferencias en el seguimiento del parámetro dolor a los 24 meses entre los grupos con y sin CH.The clinical and radiological follow-up of 202 patients with a cemented Hip Artrhoplasty (HA) was reviewed. The presence of periarticular heterotopic ossifications (PHO) and its gradation was compared i9n hybrid and bipolar arthroplasties. Risk factors related to the appearance of PHO, implants size, final alignment, operated side and relationship to the postoperative local and systemic complications were several of the parameter analyzed. The presence of PHO was 35,5% (degree I, 19%; degree II, 10%; degree III, 5% and degree IV, 1,5%); 9,9% symptomatic. A greater proportion of PHO was observed in males (p=0,005) greater zie stems (p=0,001) and patients with postoperative local complications (p=0,001). There were no statistical differences between patients with hybrid hip arthoplasties as compared to those with bipolar his arthroplasties. The Harris score showed differences as regards pain at 24 months follow-up between the groups whit an without PHO