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Recife, Brazil

Federal University of Pernambuco is a public university located in Recife, Brazil, established in 1946. UFPE has 70 undergraduate courses and 175 postgraduate courses. As of 2007, UFPE had 35,000 students and 2,000 professors. The university has three campi: Recife, Vitória de Santo Antão, and Caruaru. Its main campus, or "Cidade Universitária", has 10 centers in 149 hectares. It is located in the west part of Recife, in the Várzea neighborhood. The Law School or Faculty of Law is located downtown. UFPE ranks among the top Brazilian universities, being the ninth university both in size and scientific production, and the seventh among the federal institutes. UFPE's Center for Exact and Natural science is consistently the strongest in research production in the university. CAPES ratings are Physics Department , the Center of Informatics and the Chemistry Department .UFPE has been elected twice as the best university of north and northeast Brazil by Guia do Estudante and Banco Real .Each year over 6,000 seats are offered in a competitive entry exam . The median and average competition rate is of about 10 applicants for each seat. Wikipedia.

Melo F.P.,Federal University of Pernambuco
Trends in ecology & evolution | Year: 2013

With the decreasing affordability of protecting large blocks of pristine tropical forests, ecologists have staked their hopes on the management of human-modified landscapes (HMLs) to conserve tropical biodiversity. Here, we examine key forces affecting the dynamics of HMLs, and propose a framework connecting human disturbances, land use, and prospects for both tropical biodiversity and ecosystem services. We question the forest transition as a worldwide source of new secondary forest; the role played by regenerating (secondary) forest for biodiversity conservation, and the resilience of HMLs. We then offer a conceptual model describing potential successional trajectories among four major landscape types (natural, conservation, functional, and degraded) and highlight the potential implications of our model in terms of research agendas and conservation planning. Copyright © 2013 Elsevier Ltd. All rights reserved. Source

U-Pb zircon ages of igneous and metaigneous rocks in orogenic belts provide important information concerning the occurrence and duration of magmatic and metamorphic events whereas detrital zircon ages of metasedimentary sequences place constrains on the sources and deposition ages of supracrustal rocks. With these data, it is possible to compare and establish correlations between different provinces or between domains of the same province. A sufficiently large dataset of U-Pb ages is now available from the Borborema Province, northeastern Brazil, allowing the use of statistical methods to identify age peaks. 210 U-Pb crystallization ages from magmatic rocks and ca. 2300 U-Pb zircon ages of detrital grains from metasedimentary rocks were compiled. The igneous age spectrum shows two large age clusters. The first spans about 300Ma, from 2.25Ga to 1.97Ga. Orthogneissic complexes in the Rio Grande do Norte Domain have ages mainly between 2.22 and 2.15Ga whereas in the remainder of the province they more commonly range from 2.18 to 2.0Ga. The long duration of this magmatism is comparable to that of Neoproterozoic and Phanerozoic accretionary/collisional orogens and is inferred to have resulted from amalgamation of preexisting crustal blocks and juvenile material to the active margin of the Rio Grande do Norte Domain. The other large cluster of ages is much narrower, from 650Ma to 550Ma, which is more consistent with the duration of orogenesis in collisional belts. Orogenic granitoids older than 600Ma were not yet identified in the Rio Grande do Norte Domain, perhaps reflecting a thicker lithosphere that delayed initiation of the Brasiliano Orogeny.In contrast with the igneous rock-zircon record, the detrital zircon record requires sources with ages that span almost the whole Proterozoic eon. The presence of zircons ages in the 1.5-1.0Ga and 0.85-0.65Ga intervals, which contrasts with their absence, in the first case, or rarity, in the second case, amongst the igneous rocks, may be explained by derivation from igneous sources as yet undiscovered or removed by erosion, and/or by provenance from distal sources. The occurrence of 2.15-2.05Ga-old detrital zircons in the Rio Grande do Norte Domain and of Tonian zircons in this domain and in the Ceará Central and Médio Coreaú domains imply the inexistence of physical barriers separating the northern and southern domains of the Borborema Province during the Neoproterozoic. The results are consistent with deposition in an intracratonic setting that became the site of lithospheric extension in response to far-field stresses. The ages of the youngest detrital zircons (650-630Ma) indicate that deposition ended just before or at the beginning of the Brasiliano Orogeny. © 2014 Elsevier Ltd. Source

Batista C.,Federal University of Pernambuco
Classical and Quantum Gravity | Year: 2014

The properties of a Killing-Yano tensor of order n - 1 in an n-dimensional manifold are investigated. The integrability conditions are worked out and all metrics admitting a Killing-Yano tensor of order n - 1 are found. A connection between such tensors and a generalization of the concept of angular momentum is pointed out. A theorem on how to generate closed conformal Killing vectors using the symmetries of a manifold is proved and used to find all Killing-Yano tensors of order n - 1 of a maximally symmetric space. © 2014 IOP Publishing Ltd. Source

Vetschera R.,University of Vienna | De Almeida A.T.,Federal University of Pernambuco
Computers and Operations Research | Year: 2012

In this paper, we study the use of PROMETHEE outranking methods for portfolio selection problems. Starting from a new formulation of the PROMETHEE V method, we develop several alternative approaches based on the concepts of boundary portfolios and c-optimal portfolios. The proposed methods are compared in an extensive computational study. Results of these experiments show that methods based on the concept of c-optimal portfolios provide a good approximation to the (often computationally untractable) PROMETHEE ranking of all portfolios, while requiring only small computational effort even for large problems. For smaller problems, a PROMETHEE ranking of all boundary portfolios can be performed and provides a close approximation of the total ranking. © 2011 Elsevier Ltd. All rights reserved. Source

Batista C.,Federal University of Pernambuco
General Relativity and Gravitation | Year: 2013

It is well known that the classification of the Weyl tensor in Lorentzian manifolds of dimension four, the so called Petrov classification, was a great tool to the development of general relativity. Using the bivector approach it is shown in this article a classification for the Weyl tensor in all four-dimensional manifolds, including all signatures and the complex case, in an unified and simple way. The important Petrov classification then emerges just as a particular case in this scheme. The boost weight classification is also extended here to all signatures as well to complex manifolds. For the Weyl tensor in four dimensions it is established that this last approach produces a classification equivalent to the one generated by the bivector method. © 2013 Springer Science+Business Media New York. Source

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