Geometric Phase for Fermionic Quasiparticles Scattering by Disgyration in Superfluids

We consider a Volovik's analog model for description of a topological defects in a superfluid and we investigate the scattering of quasiparticles in this background. The analog of the gravitational Aharonov-Bohm in this system is found. An analysis of this problem employing loop variables is considered and corroborates for the existence of the Aharonov-Bohm effect in this system. The results presented here may be used to study the Aharonov-Bohm effect in superconductors.Comment: 7 pages, to appear in Europhys. Let

The Two-Component Virial Theorem and the Physical Properties of Stellar Systems

Motivated by present indirect evidences that galaxies are surrounded by dark matter halos, we investigate whether their physical properties can be described by a formulation of the virial theorem which explicitly takes into account the gravitational potential term representing the interaction of the dark halo with the barionic or luminous component. Our analysis shows that the application of such a ``two-component virial theorem'' not only accounts for the scaling relations displayed, in particular, by elliptical galaxies, but also for the observed properties of all virialized stellar systems, ranging from globular clusters to galaxy clusters.Comment: 13 pages, 2 figures, LaTeX, corrected few typos. This version matches the published versio

Potencial produtivo do girassol consórciado com feijão no semiárido baiano.

O semiárido do nordeste baiano tem condições edafoclimáticas propícias ao desenvolvimento do girassol, à semelhança do que ocorre com o feijão. Assim foi objetivo deste trabalho conhecer o desempenho produtivo de cultivares de girassol nesta região, quando cultivadas em monocultivo e em consórcio com feijão, visando ampliar a área de adoção desta cultura. Os plantios experimentais foram realizados no município de Coronel João Sá, localizado no semiárido da Bahia no ano de 2010. Foram utilizadas os híbridos de girassol NTO 2.0, NTO 3.0, AGUARÁ 4, AGUARÁ 6, M 734, BRS 321, BRS 322, BRS 323, BRS G 26, OLISUN, PARAISO 22, PARAISO 33, PARAISO 65, HELIO 251, HELIO 253, HELIO 863 e as Variedades BRS 324, EMBRAPA122, MULTISSOL e CATISSOL. No consórcio utilizou-se a variedade de feijão carioca BRS Requinte. Foi estabelecido o rendimento de grãos de cada cultivar em cada um dos sistemas, monocultivo e consorciado. Na média, os rendimentos de grãos foram de 1.858 kg/ha, em monocultivo e 2.443 kg/ha, em consórcio com feijão. O sistema de plantio em consórcio com feijão foi mais favorável ao cultivo do girassol. A média geral de rendimento de grãos de girassol, na média dos sistemas de plantio adotados, foi de 2.151 kg/ha. As cultivares AGUARÁ 6, NTO 3.0, M 734, AGUARÁ 4, NTO 2.0, BRS 322, BRS 323, BRS G 26, OLISUN, HELIO 253 e HELIO 251, com rendimentos acima da média geral podem ser indicadas para o cultivo de girassol na região semiárida do Nordeste baiano, tanto para o monocultivo, como para o consórcio com o feijão. SUNFLOWER YIELD IN INTERCROPPING WITH BEAN IN THE SEMI-ARID OF BAHIA STATE. The semi-arid northeastern region of Bahia State has soil and climatic conditions for conducive to the development of the sunflower. Just aim of this study was to know the productive performance of sunflower cultivars in this region, when grown in monoculture and intercropping with bean. The experimental plantation were made in Coronel João Sá city, located in semi-arid region of Bahia in 2010. Were utilized the sunflower hybrids NTO 2.0, NTO 3.0, Aguará 4, Aguará 6, M 734, BRS 321, BRS 322, BRS 323, BRS G 26, OLISUN, PARAISO 22, PARAISO 33, PARAISO 65, HELIO 251, HELIO 253, HELIO 863 and the Varieties BRS 324, EMBRAPA122, MULTISSOL and CATISSOL. The bean variety BRS Requinte was used in the intercropping. It was established grain yield of each cultivar in each of the systems, monoculture and intercropping. On average, grain yields were 1,858 kg/ha in monoculture and 2,443 kg/ha in intercropping with bean. The planting system in intercropping with bean was more favorable to the sunflower cultivation. The average grain yield of sunflower in the mean of the cropping systems adopted, was 2,151 kg/ha. The Cultivars Aguará 6, NTO 3.0, M 734, Aguará 4, NTO 2.0, BRS 322, BRS 323, BRS G 26, OLISUN, HELIO 253 and HELIO 251, with yields above the general average can be indicated for the sunflower cultivation in the semi-arid northeastern region of Bahia in monoculture and in intercropping with bean