Contribución al conocimiento del género Patella Linné 1758, en la isla de Mallorca

Abstract not availabl

En el centro de todas las miradas : una aproximación a la historiografía de la frenología

Desde finales del siglo XIX, la frenología fue considerada, en el mejor de los casos, como una pseudo-ciencia popularizada por charlatanes. Durante la década de 1970 los representantes de la nueva historia social de la ciencia y de la medicina la escogieron como un caso ejemplar para penetrar en los procesos de delimitación de la ortodoxia científica. Desde entonces, las diferentes aproximaciones a la frenología han contribuido a cambiar una imagen del siglo XIX que asignaba un peso excesivo a los procesos de profesionalización y tecnificación de la ciencia y de la medicina. En este artículo se analizan las principales aportaciones al estudio de la frenología realizadas durante las últimas tres décadas por la historiografía francesa y anglosajona y se señalan algunos aspectos que deberían recibir mayor atención en futuras investigaciones

Estructura de las poblaciones y crecimiento de Littorina neritoides (L. 1758) (Mollusca, Gastropoda) en las costas de las Islas Baleares

Abstract not availabl

Distribución de los pigmentos en el sustrato rocoso de la zona supralitoral del litoral balear

Abstract not availabl

Graph-based solution batch management for Multi-Objective Evolutionary Algorithms

In Alberto and Mateo [2], 2004, a graph-based structure used for manipulating populations of Multi-Objective Evolutionary Algorithms in a more efficient way than the structures existing at that point was defined. In this paper, an improvement of such tool is presented. It consists of the simultaneous insertion of a set of solutions (solution batch), instead of a single one, into the created graph structure. Furthermore, two experiments devoted to comparing the behavior of the new algorithms with the original version from Alberto and Mateo [2] and with a well-known non-dominated sorting algorithm are carried out. The first shows how the new version outperforms the original one in time and number of Pareto comparisons. The second experiment shows a reduction in the time needed in all the cases and an important reduction in the number of Pareto comparisons when inserting chains of dominated solutions. From these experiments it is verified that, in general, the new proposals save computational time and, in the majority of the cases, the number of Pareto comparisons carried out for the insertion. In addition, when the new proposals outperform the others, they increase their gain over them as the size of the population and/or the size of the batch increases. The new tool can also be used, for example, in parallel genetic algorithms such as the ones based on islands, to carry out the migrations of the solutions

A Chemical Composition Survey of the Iron-Complex Globular Cluster NGC 6273 (M 19)

Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations of stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been recognized as a member of this "iron-complex" cluster class, and we provide here a chemical and kinematic analysis of > 300 red giant branch (RGB) and asymptotic giant branch (AGB) member stars using high resolution spectra obtained with the Magellan-M2FS and VLT-FLAMES instruments. Multiple lines of evidence indicate that NGC 6273 possesses an intrinsic metallicity spread that ranges from about [Fe/H] = -2 to -1 dex, and may include at least three populations with different [Fe/H] values. The three populations identified here contain separate first (Na/Al-poor) and second (Na/Al-rich) generation stars, but a Mg-Al anti-correlation may only be present in stars with [Fe/H] > -1.65. The strong correlation between [La/Eu] and [Fe/H] suggests that the s-process must have dominated the heavy element enrichment at higher metallicities. A small group of stars with low [alpha/Fe] is identified and may have been accreted from a former surrounding field star population. The cluster's large abundance variations are coupled with a complex, extended, and multimodal blue horizontal branch (HB). The HB morphology and chemical abundances suggest that NGC 6273 may have an origin that is similar to omega Cen and M 54.Comment: Accepted for Publication in The Astrophysical Journal; 50 pages; 18 figures; 8 tables; higher resolution figures are available upon request or in the published journal articl

Políticas culturales, transformaciones urbanas e higienización social en la Barcelona contemporánea

During these last three decades, culture has played a fundamental role in great urban transformations. However, they have involved some changes in social and cultural field not only in downtown Western cities, but also their suburbs. This papers will try to show how cultural strategies for urban renewal processes carried out by Barcelona’s local City Hall has meant, in last term, social homogenization strategies. This paper will end by showing how recent convergence between conservative and liberal sectors of ruling classes of Catalan capital about which cultural strategies must be applied for urban renewal processes could mean the consolidation of new topographies of power in contemporary metropolitan Barcelona.Desde las últimas tres décadas, la cultura ha venido desempeñando un papel fundamental en las grandes transformaciones urbanas de las ciudades occidentales. Sin embargo, tales transformaciones han conllevado también notables cambios en el ámbito social y cultural no solamente en los centros urbanos sinó también en los áreas suburbanas Este artículo pretende mostrar cómo las estrategias culturales llevadas a cabo por el Ayuntamiento de Barcelona para la renovación urbana de su centro histórico así como también sus suburbios no han dejado de ser, en última instancia, estrategias para la homogeneización e higienización social de la ciudad. El artículo finaliza realizando varias hipótesis abiertas sobre la reciente convergencia, en el ámbito de las políticas culturales de la ciudad de Barcelona, entre los sectores nacionalistas conservadores y progresistas de la capital catalana y que explicitan, al menos de manera hipotética, la eclosión de nuevas topografías del poder en la Barcelona metropolitana contemporánea.Depuis les trois dernières décennies, la culture a joué un rôle important dans la transformation urbaine des villes européens. Toutefois, ces changements ont également entraîné des changements significatifs dans le développement social et culturel non seulement dans les centres urbains mais également dans les zones suburbaines Cet article vise à montrer comment les stratégies culturels poursuivis par le conseil municipal de Barcelone pour sa rénovation urbaine du centre historique et de sa banlieue sont également stratégies d’homogénéisation sociale et d’assainissement de la ville. L’article conclut en faisant plusieurs hypothèses ouvertes sur la convergence récente dans le domaine des politiques culturelles de la ville de Barcelone, entre les secteurs conservateurs nationalistes et progressistes de la capitale catalane et qui expliquent, au moins hypothétiquement, l’émergence de nouvelles topographies de pouvoir dans le Barcelona métropolitaine contemporaine

Exploring the Chemical Composition and Double Horizontal Branch of the Bulge Globular Cluster NGC 6569

Photometric and spectroscopic analyses have shown that the Galactic bulge cluster Terzan 5 hosts several populations with different metallicities and ages that manifest as a double red horizontal branch (HB). A recent investigation of the massive bulge cluster NGC 6569 revealed a similar, though less extended, HB luminosity split, but little is known about the cluster's detailed chemical composition. Therefore, we have used high-resolution spectra from the Magellan-M2FS and VLT-FLAMES spectrographs to investigate the chemical compositions and radial velocity distributions of red giant branch and HB stars in NGC 6569. We found the cluster to have a mean heliocentric radial velocity of -48.8 km/s (sigma = 5.3 km/s; 148 stars) and a mean [Fe/H] =-0.87 dex (19 stars), but the cluster's 0.05 dex [Fe/H] dispersion precludes a significant metallicity spread. NGC 6569 exhibits light- and heavy-element distributions that are common among old bulge/inner Galaxy globular clusters, including clear (anti)correlations between [O/Fe], [Na/Fe], and [Al/Fe]. The light-element data suggest that NGC 6569 may be composed of at least two distinct populations, and the cluster's low mean [La/Eu] = -0.11 dex indicates significant pollution with r-process material. We confirm that both HBs contain cluster members, but metallicity and light-element variations are largely ruled out as sources for the luminosity difference. However, He mass fraction differences as small as delta Y ~ 0.02 cannot be ruled out and may be sufficient to reproduce the double HB.Comment: 72 pages, 14 figures, 8 tables; published in The Astronomical Journal; electronic versions of all tables are available in the published versio