The star cluster system of the 3 Gyr old merger remnant NGC 1316: Clues from optical and near-infrared photometry

The giant merger remnant galaxy NGC 1316 (Fornax A) is an ideal probe for studying the long-term effects of a past major merger on star cluster systems, given its spectroscopically derived merger age of ~3 Gyr which we reported in a recent paper. Here we present new ground-based, large-area optical and near-IR imaging of star clusters in NGC 1316, complemented with deep HST/WFPC2 imaging. We find that the optical-near-IR colours and luminosities of the brightest ~10 clusters in NGC 1316 are consistent with those of intermediate-age (2-3 Gyr) populations. Unlike `normal' giant ellipticals, the B-I colour distribution of clusters in NGC 1316 is not clearly bimodal. However, the luminosity functions (LFs) of the blue and red parts of the cluster colour distribution are different: The red cluster LF is well represented by a power law with index -1.2 +/- 0.3, extending to about 1.5 mag brighter (in B) than those of typical giant ellipticals. In contrast, the shape of the blue cluster LF is consistent with that of `normal' spiral and elliptical galaxies. We conclude that the star cluster system of NGC 1316 is a combination of a population of age ~3 Gyr having roughly solar metallicity and a population of old, metal-poor clusters which probably belonged to the pre-merger galaxies. After the 3 Gyr old, metal-rich clusters fade to an age of 10 Gyr, they will form a red `peak' in a bimodal cluster colour distribution. This `red peak' will have a colour consistent with that found in `normal, old' giant ellipticals of the same galaxy luminosity (taking age dimming into account). These features of the star cluster system of NGC 1316 are fully consistent with scenarios for forming `normal' giant elliptical galaxies through gas-rich mergers at look-back times \ga 10 Gyr.Comment: 21 pages, LaTeX format, figures included using psfig.sty. Accepted by MNRAS. Abstract below is abridged (full abstract in paper). Used 8-bit mapping to limit size of figures (24-bit mapping in MNRAS paper

Ultrastructure Expansion Microscopy (U-ExM) in Trypanosoma cruzi: localization of tubulin isoforms and isotypes

Ultrastructure Expansion Microscopy (U-ExM) is a recently developed technique that enables the increase of the spatial resolution within a cell or a tissue for microscopic imaging by physically expanding the sample. For the first time, I report a detailed protocol validating the use of U-ExM in Trypanosoma cruzi and quantifying the expansion factors of different subcellular compartments. I was able to determine the localization patterns of different tubulin isoforms, such as α-tubulin and β-tubulin. Also, I immunolocalized acetylated and tyrosinated α-tubulin isotypes in epimastigotes and use mitochondrial cell-permeable dyes to identify this organelle. Finally, U-ExM was also performed in trypomastigotes and amastigotes validating this technique in all life cycle stages of T. cruzi.Fil: Alonso, Victoria Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin

Velocity dispersion estimates of APM galaxy clusters

We present 83 new galaxy radial velocities in the field of 18 APM clusters with redshifts between 0.06 and 0.13. The clusters have Abell identifications and the galaxies were selected within 0.75 h$^{-1}$Mpc in projection from their centers. We derive new cluster velocity dispersions for 13 clusters using our data and published radial velocities. We analyze correlations between cluster velocity dispersions and cluster richness counts as defined in Abell and APM catalogs. The correlations show a statistically significant trend although with a large scatter suggesting that richness is a poor estimator of cluster mass irrespectively of cluster selection criteria and richness definition. We find systematically lower velocity dispersions in the sample of Abell clusters that do not fulfill APM cluster selection criteria suggesting artificially higher Abell richness counts due to contamination by projection effects in this subsample.Comment: Accepted for publication in MNRA

Construction of three new Gateway® expression plasmids for Trypanosoma cruzi

We present here three expression plasmids for Trypanosoma cruzi adapted to the Gateway® recombination cloning system. Two of these plasmids were designed to express trypanosomal proteins fused to a double tag for tandem affinity purification (TAPtag). The TAPtag and Gateway® cassette were introduced into an episomal (pTEX) and an integrative (pTREX) plasmid. Both plasmids were assayed by introducing green fluorescent protein (GFP) by recombination and the integrity of the double-tagged protein was determined by western blotting and immunofluorescence microscopy. The third Gateway adapted vector assayed was the inducible pTcINDEX. When tested with GFP, pTcINDEX-GW showed a good response to tetracycline, being less leaky than its precursor (pTcINDEX).Fil: Alonso, Victoria Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmaceuticas. Departamento de Microbiología; ArgentinaFil: Ritagliati, Carla. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Cribb, Pamela. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmaceuticas. Departamento de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Serra, Esteban Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; Argentin

El siglo XIX como campo de estudio de la masculinidad: el artista y su representación en el ámbito español

A pesar de la generalización de los estudios multidisciplinares sobre género, en el campo de la historia del arte aún no se ha profundizado cuanto es necesario para comprender de qué modo las construcciones de identidades de género han afectado a las representaciones plásticas. El presente estudio forma parte de una investigación más profunda aún en proceso, vinculada al desarrollo de una tesis doctoral, y por lo tanto no pretende aportar conclusiones definitivas sino poner en común un estado de la cuestión respecto a la necesidad del tema tratado. Nuestro objetivo radica en plantear las razones por las que la historia contemporánea del arte no puede ser entendida en lo que respecta a cuestiones de género si no adoptamos una metodología que trate de manera igualitaria la construcción social, histórica y artística de la masculinidad y la feminidad. Para ello hemos tomado como caso de estudio la figura del artista y hemos analizado por qué se ha considerado eminentemente masculina y cómo podemos abordar temas como masculinidad, asociacionismo y el sistema artístico español del siglo XIX para entender el discurso de género en torno al hombre artista.Despite the generalization of multidisciplinary Gender Studies, Art History has not yet gone deep enough about how gendered identities have affected visual representations. Our study is part of a deeper research still in progress related to our PhD thesis; it doesn’t expect to provide definitive conclusions but to share the necessity of this issue. Our aim is to expose the reasons why contemporary Art History cannot be understood in gender subjects as long as we don’t assume a methodology which deals equally with social, historic and artistic constructions of masculinity and feminity. We have adopted as a case of study the role of the artist, and we have analyzed why it has traditionally been considered as a male figure and how we can deal with issues like masculinity, associating and Nineteenth-Century Spanish artistic system to improve our understanding about gender and men-artists

KIERKEGAARD, Soren, Escritos de Soren Kierkegaard.

Sin resume

The Stellar Populations of NGC 3109: Another Dwarf Irregular Galaxy with a Population II Stellar Halo

We have obtained V and I-band photometry for about 17500 stars in the field of the dwarf irregular galaxy NGC3109, located in the outskirts of the Local Group. The photometry allows us to study the stellar populations present inside and outside the disk of this galaxy. From the VI color-magnitude diagram we infer metallicities and ages for the stellar populations in the main body and in the halo of NGC3109. The stars in the disk of this galaxy have a wide variety of ages, including very young stars with approximately 10^7 yr. Our main result is to establish the presence of a halo consisting of population II stars, extending out to about 4.5 arcmin (or 1.8 kpc) above and below the plane of this galaxy. For these old stars we derive an age of > 10 Gyr and a metallicity of [Fe/H] = -1.8 +/- 0.2. We construct a deep luminosity function, obtaining an accurate distance modulus (m-M)_0 = 25.62 +/- 0.1 for this galaxy based on the I-magnitude of the red giant branch (RGB) tip and adopting E(V-I) = 0.05.Comment: Accepted for publication in the Astronomical Journal 23 pages, latex, 12 Figures (Fig 1 not available in electronic format

A posteriori error estimates in finite element acoustic analysis

We present an a posteriori error estimator for the approximations of the acoustic vibration modes obtained by a finite element method which does not present spurious or circulation modes for non zero frequencies. We prove that the proposed estimator is equivalent to the error in the approximation of the eigenvectors up to higher order terms with constants independent of the eigenvalues. Numerical results for some test examples are presented which show the good behavior of the estimator when it is used as local error indicator for adaptive refinement.Facultad de Ciencias Exacta

Galaxy Concentration Index in Low X-ray Luminosity Galaxy Clusters

Abstracts: Using a sample of 10 low x-ray luminosity galaxy clusters (Nilo Castellón et al. 2013B), we studied the properties of 146 galaxies classified as members in a redshift range of 0.185 4). Contrary to these results, for late-type galaxies we found smaller C values for the lower redshift clusters. These results could be associated to the morphological evolution of galaxies, as proposed by different authors (Poggianti et al. 2009, Dressler et al. 2009) for rich clusters.Fil: Alonso, María Victoria. Conicet. Instituto de Astronomía Teórica y Experimental; Argentina.publishedVersionOtras Ciencias Naturales y Exacta