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1.
J Homosex ; : 1-31, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36250980

RESUMO

Queerness and Catholicism have historically been at odds with one another. The Church's condemnation of queer individuals was pervasive globally for centuries, yet one way queerness and Catholicism converge is via Saint Sebastian depictions. The purpose of this research is to examine how and why Sebastian, a Catholic saint, has come to serve as an icon for the queer community as well as how dress has been used in depicting shifting representations of the Saint from the 15th to 21st centuries. Drawing upon the historic method, we critically analyze the meanings present in imagery of Saint Sebastian. Through our study of portrayals of the Saint, several key themes have emerged. Several of these contemporary artworks incorporated written language that reifies sainthood and associated suffering. Furthermore, many artworks' overall composition surrounding Saint Sebastian reinforced sainthood through contextual visual elements. Ambivalence in depictions of Saint Sebastian's fleshy body was apparent, with an emphasis on depicting Sebastian within the context of his executions. A gap in time periods and differing artwork styles was observed, with many of our examples being either from the Renaissance or post 1960s. Finally, many of the contemporary artworks surveyed included overt signifiers of queerness, with minimal references to subtle queerness.

2.
Nature ; 531(7596): 610-3, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27001693

RESUMO

Elements heavier than zinc are synthesized through the rapid (r) and slow (s) neutron-capture processes. The main site of production of the r-process elements (such as europium) has been debated for nearly 60 years. Initial studies of trends in chemical abundances in old Milky Way halo stars suggested that these elements are produced continually, in sites such as core-collapse supernovae. But evidence from the local Universe favours the idea that r-process production occurs mainly during rare events, such as neutron star mergers. The appearance of a plateau of europium abundance in some dwarf spheroidal galaxies has been suggested as evidence for rare r-process enrichment in the early Universe, but only under the assumption that no gas accretes into those dwarf galaxies; gas accretion favours continual r-process enrichment in these systems. Furthermore, the universal r-process pattern has not been cleanly identified in dwarf spheroidals. The smaller, chemically simpler, and more ancient ultrafaint dwarf galaxies assembled shortly after the first stars formed, and are ideal systems with which to study nucleosynthesis events such as the r-process. Reticulum II is one such galaxy. The abundances of non-neutron-capture elements in this galaxy (and others like it) are similar to those in other old stars. Here, we report that seven of the nine brightest stars in Reticulum II, observed with high-resolution spectroscopy, show strong enhancements in heavy neutron-capture elements, with abundances that follow the universal r-process pattern beyond barium. The enhancement seen in this 'r-process galaxy' is two to three orders of magnitude higher than that detected in any other ultrafaint dwarf galaxy. This implies that a single, rare event produced the r-process material in Reticulum II. The r-process yield and event rate are incompatible with the source being ordinary core-collapse supernovae, but consistent with other possible sources, such as neutron star mergers.

3.
Nature ; 464(7285): 72-5, 2010 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-20203604

RESUMO

Current cosmological models indicate that the Milky Way's stellar halo was assembled from many smaller systems. On the basis of the apparent absence of the most metal-poor stars in present-day dwarf galaxies, recent studies claimed that the true Galactic building blocks must have been vastly different from the surviving dwarfs. The discovery of an extremely iron-poor star (S1020549) in the Sculptor dwarf galaxy based on a medium-resolution spectrum cast some doubt on this conclusion. Verification of the iron-deficiency, however, and measurements of additional elements, such as the alpha-element Mg, are necessary to demonstrate that the same type of stars produced the metals found in dwarf galaxies and the Galactic halo. Only then can dwarf galaxy stars be conclusively linked to early stellar halo assembly. Here we report high-resolution spectroscopic abundances for 11 elements in S1020549, confirming its iron abundance of less than 1/4,000th that of the Sun, and showing that the overall abundance pattern follows that seen in low-metallicity halo stars, including the alpha-elements. Such chemical similarity indicates that the systems destroyed to form the halo billions of years ago were not fundamentally different from the progenitors of present-day dwarfs, and suggests that the early chemical enrichment of all galaxies may be nearly identical.

4.
Nature ; 454(7208): 1096-7, 2008 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-18756252

RESUMO

The Milky Way has at least twenty-three known satellite galaxies that shine with luminosities ranging from about a thousand to a billion times that of the Sun. Half of these galaxies were discovered in the past few years in the Sloan Digital Sky Survey, and they are among the least luminous galaxies in the known Universe. A determination of the mass of these galaxies provides a test of galaxy formation at the smallest scales and probes the nature of the dark matter that dominates the mass density of the Universe. Here we use new measurements of the velocities of the stars in these galaxies to show that they are consistent with them having a common mass of about 10(7) within their central 300 parsecs. This result demonstrates that the faintest of the Milky Way satellites are the most dark-matter-dominated galaxies known, and could be a hint of a new scale in galaxy formation or a characteristic scale for the clustering of dark matter.

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