Copia Retrotransposon in the Zaprionus Genus: Another Case of Transposable Element Sharing with the Drosophila melanogaster Subgroup

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sequence heterogeneity and phylogenetic relationships between the copia retrotransposon in Drosophila species of the repleta and melanogaster groups

Although the retrotransposon copia has been studied in the melanogaster group of Drosophila species, very little is known about copia dynamism and evolution in other groups. We analyzed the occurrence and heterogeneity of the copia 5' LTR-ULR partial sequence and their phylogenetic relationships in 24 species of the repleta group of Drosophila. PCR showed that copia occurs in 18 out of the 24 species evaluated. Sequencing was possible in only eight species. The sequences showed a low nucleotide diversity, which suggests selective constraints maintaining this regulatory region over evolutionary time. on the contrary, the low nucleotide divergence and the phylogenetic relationships between the D. willistoni/Zaprionus tuberculatus/melanogaster species subgroup suggest horizontal transfer. Sixteen transcription factor binding sites were identified in the LTR-ULR repleta and melanogaster consensus sequences. However, these motifs are not homologous, neither according to their position in the LTR-ULR sequences, nor according to their sequences. Taken together, the low motif homologies, the phylogenetic relationship and the great nucleotide divergence between the melanogaster and repleta copia sequences reinforce the hypothesis that there are two copia families.

The copia retrotransposon and horizontal transfer in Drosophila willistoni

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Modelo AC para el despacho combinado de contratos bilaterales y bolsa de energía considerando restricciones de seguridad

Reliability is a key aspect in power system design and planning. Maintaining a reliable power system is a very important issue for their design and operation. Under the new competitive framework of the electricity sector, power systems find ever more and more strained to operate near their limits. Under this new scenario, it is crucial for the system operator to use tools that facilitate an energy dispatch that minimizes possible power cuts. This paper presents a mathematical model to calculate an energy dispatch that considers security constraints (single contingencies in transmission lines and transformers). The model involves pool markets and fixed bilateral contracts. Traditional methodologies that include security constraints are usually based in multistage dispatch processes. In this case, we propose a single-stage model that avoids the economic inefficiencies which result when conventional multi-stage dispatch approaches are applied. The proposed model includes an AC representation of the transport system and allows calculating the cost overruns incurred in due to reliability restrictions. We found that complying with fixed bilateral contracts, when they go above certain levels, might lead to congestion problems in transmission lines.

Elementos de transposição no gênero Zaprionus (Diptera, Drosophilidae): estudos genômicos e evolutivos em ênfase nos retrotensposons copia, gypsy e micropia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ejes estratégicos de la seguridad hemisférica en los gobiernos de George W. Bush y Barack Obama

The paper approaches the U.S. perceptions about the sources of insecurity from Latin America, considered a low risk area and priority of its foreign policy. El análisis se concentra en la evaluación de las amenazas y desafíos a sus intereses estratégicos y las modalidades de actuación privilegiadas en la esfera regional, en que se verifican coincidencias entre las administraciones Demócratas y Republicanas en la adopción de un liderazgo con prerrogativas clasificatorias sobre los tipos de régimen político, con una agenda concebida como promoción de la convergencia hemisférica de democracias y economías liberales. The analysis focuses on assessing the threats and challenges to its strategic interests and privileged modes of action at the regional level, which verifies similarities between Republican and Democratic administrations in taking a leadership prerogatives qualifiers on the types political regime, with an agenda designed as promoting hemispheric convergence of liberal democracies and economies. En ese contexto, cabe destacar la prioridad atribuida a los países de la Alternativa Bolivariana para las Américas (ALBA) como eje opositor de sus políticas. In this context, include the priority given to the countries of the Bolivarian Alternative for the Americas (ALBA) as the linchpin of his political opponent.

Large distribution and high sequence identity of a Copia-type retrotransposon in angiosperm families

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)