Zinc abundances in Galactic bulge field red giants: implications for DLA systems

Zinc in stars is an important reference element because it is a proxy to Fe in studies of damped Lyman-alpha systems, permitting a comparison of chemical evolution histories of bulge stellar populations and DLAs. In terms of nucleosynthesis, it behaves as an alpha element because it is enhanced in metal-poor stars. The aim of this work is to derive the iron-peak element Zn abundances in 56 bulge giants from high resolution spectra. These results are compared with data from other bulge samples, as well as from disk and halo stars, and damped Lyman-alpha systems, in order to better understand the chemical evolution in these environments. High-resolution spectra were obtained using FLAMES+UVES on the Very Large Telescope. We find [Zn/Fe]=+0.24+-0.02 in the range -1.3 < [Fe/H] < -0.5 and [Zn/Fe]=+0.06+-0.02 in the range -0.5 < [Fe/H] -0.1, it shows a spread of -0.60 < [Zn/Fe] < +0.15, with most of these stars having low [Zn/Fe]<0.0. These low zinc abundances at the high metallicity end of the bulge define a decreasing trend in [Zn/Fe] with increasing metallicities. A comparison with Zn abundances in DLA systems is presented, where a dust-depletion correction was applied for both Zn and Fe. Finally, we present a chemical evolution model of Zn enrichment in massive spheroids, representing a typical classical bulge.Comment: Accepted in Astronomy & Astrophysics, in press Date of acceptance: 13/05/2015. 19 pages, 14 Figs in Astronomy & Astrophysics, 201

Dinâmica da liberação de nutrientes de compostos orgânicos e exigências nutricionais do abacaxizeiro BRS Imperial.

As adubações para diferentes culturas trabalhadas na Embrapa Mandioca e Fruticultura são recomendadas em função das fontes de corretivos de solo e dos fertilizantes convencionais. Com exceção da cultura da banana, inexistem recomendações consolidadas com critérios científicos para fertilização orgânica ou orgânica enriquecida com fontes não convencionais. Nesse sentido, a compreensão do comportamento dos materiais genéticos frente a esse sistema de produção torna-se importante

Coasting cosmologies with time dependent cosmological constant

The effect of a time dependent cosmological constant is considered in a family of scalar tensor theories. Friedmann-Robertson-Walker cosmological models for vacumm and perfect fluid matter are found. They have a linear expansion factor, the so called coasting cosmology, the gravitational "constant" decreace inversely with time; this model satisfy the Dirac hipotesis. The cosmological "constant" decreace inversely with the square of time, therefore we can have a very small value for it at present time.Comment: 7 pages, latex file (ijmpal macro), accepted for publication in Int. Mod. Phys.

Processo de Seleção Escape para Obtenção de Plantas de Pessegueiro e Ameixeira com Alta Sanidade.

bitstream/item/30951/1/Circular-84.pd

Estudo dos solos do município de Morro Redondo.

bitstream/item/41408/1/Morro-Redondo.pdf; bitstream/item/41409/1/mapa-geomorfologia-e-solos.pdf; bitstream/item/41410/1/mapa-solos.pdf; bitstream/item/41411/1/mapa-uso-das-terras.pd

Estudo dos solos do município de Herval.

bitstream/item/41396/1/Herval.pdf; bitstream/item/41397/1/mapa-geomorfologia.pdf; bitstream/item/41398/1/mapa-solos.pdf; bitstream/item/41399/1/mapa-uso-das-terras.pd

Partial Papillary Muscle Rupture after Myocardial Infarction and Early Severe Obstructive Bioprosthetic Valve Thrombosis: an Unusual Combination

Mechanical complications after myocardial infarction (MI) have become uncommon since the introduction of primary angioplasty. They can lead to a rapid clinical deterioration and a fatal outcome, with patient’s survival being dependent on their prompt recognition and intervention. We describe a case of two rare mechanical complications: a partial papillary muscle rupture after MI, followed by an early severe obstructive thrombosis of the implanted bioprosthetic valve.info:eu-repo/semantics/publishedVersio

Estudo dos solos do município de Rio Grande.

bitstream/item/41404/1/Rio-Grande.pdf; bitstream/item/41405/1/mapa-geomorfologia-e-solos.pdf; bitstream/item/41406/1/mapa-solos.pdf; bitstream/item/41407/1/mapa-uso-da-terra.pd