On the Ancestral Compatibility of Two Phylogenetic Trees with Nested Taxa

Compatibility of phylogenetic trees is the most important concept underlying widely-used methods for assessing the agreement of different phylogenetic trees with overlapping taxa and combining them into common supertrees to reveal the tree of life. The notion of ancestral compatibility of phylogenetic trees with nested taxa was introduced by Semple et al in 2004. In this paper we analyze in detail the meaning of this compatibility from the points of view of the local structure of the trees, of the existence of embeddings into a common supertree, and of the joint properties of their cluster representations. Our analysis leads to a very simple polynomial-time algorithm for testing this compatibility, which we have implemented and is freely available for download from the BioPerl collection of Perl modules for computational biology.Comment: Submitte

Verificación de Autómatas y Gramáticas

La verificación de autómatas de estados finitos y de pila, y de gramáticas libres de contexto puede ser materia de enseñanza en una asignatura de Lenguajes Formales usando las metodologías descritas en este artículo. Se intenta mostrar que para los autómatas y gramáticas la verificación es posible en la práctica diaria. Las metodologías se basan en la asociación de significados (lenguajes) a los símbolos que aparecen en la solución de un problema (estado, contenido de la pila o variable de una gramática). Los significados corresponden a ciertas propiedades que son invariantes a través de las configuraciones. Los estudiantes de segundo curso de Ingeniería Informática han sido capaces de aplicar las metodologías y aumentar sus elementos de juicio a fin de asociar los significados de los símbolos que aparecen en la solución de un problema

Productivity and preferences by forage of dairy cows grazing an intensive silvopastoral system from high Andean area of Roncesvalles, Tolima

P?ginas 29-35Recurso Electr?nicoSe evalu? la productividad de vacas lecheras y la preferencia de forraje en un sistema silvopastoril (SSP) de sauco (Sambucus nigra) asociado con pasto kikuyo (Pennisetum clandestinum) en una ?rea alto andina del Tolima. Se confirm? una buena interacci?n de las especies en el SSP, bajo las condiciones clim?ticas de la zona, pues mostraron caracter?sticas productivas similares a otras zonas, reportadas en art?culos cient?ficos. Las vacas prefirieron la gram?nea respecto al sauco, pero la producci?n de leche mostr? diferencias significativas entre tratamientos, revelando efectos ben?ficos del SSP sobre la producci?n de la leche.ABSTRACT. Productivity of dairy cows and preferences by forage were evaluated in a silvopastoral system (SSP) of elderberry (Sambucus nigra) with kikuyu (Pennisetum clandestinum)in a high Andean area from Tolima. Results confirm a good interaction between these species in SSP, under specific climate conditions of the area, because the SSP showed productive characteristics similar to other areas, reported in scientific papers. Cows preferred intake grasses rather than elderberry forage, but milk production was better in SSP than Control, suggesting benefic effects of SSP on milk production

O fortelacimento e a manutenção da marca LAB REDE no estado do Rio de Janeiro

Este trabalho constitui-se num estudo acerca do tema: O fortalecimento e a manutenção da marca LAB REDE no Estado do Rio de Janeiro. Procura-se que seja o ponto de partida para conscientizar os proprietários das empresas acionistas do LAB REDE S/A sobre a importância do fortalecimento dessa marca, tornando-se duradoura no mercado. Esse ganho competitivo pode fazer com que cada uma das empresas acionistas, em seus locais de origem, se tornem fortes e sobrevivam no cenário atual onde as grandes marcas, algumas delas multinacionais, assumem o mercado brasileiro da prestação privada de serviços laboratoriais. O processo de globalização tem atingido, de forma rápida e avassaladora, diversos segmentos de mercado, transformando as relações entre empresas e países. Essas transformações afetam diretamente os mercados de bens, serviços e capital, e ditam as novas regras de base societária, tecnológica, produtiva, comercial e financeira do capitalismo internacional. Segundo Lima (2008), o setor de serviços já detém a maior participação no PIB dos países desenvolvidos e no de muitos dos países em desenvolvimento. Este trabalho, desenvolvido por meio de uma pesquisa-ação, envolveu os dirigentes das empresas acionistas, mediante a aplicação de uma entrevista semiestruturada. As informações obtidas foram confrontadas com modelos teóricos, buscando corroborar a hipótese básica de que a estratégia adotada tem estreito vínculo com a visão de mercado internacional adotada pelos empreendedores.This research approaches the maintenance of LAB REDE brand in Rio de Janeiro - Brazil. It looks for the starting point of how to show to LAB REDE Shareholders the importance of brand improvement, vital to company existence. This competitive gain can make each shareholders become more competitive and improve their survival chances in the current scenario where the major brands, some multinationals, assume more and more the laboratory services in Brazilian market. The process of globalization reached quickly and overwhelming several market segments, transforming the relations between companies and countries. These changes affects directly the goods, services and capital markets, and dictate the new rules of corporate databases, technological, production, trade and finance of international capitalism. According to Lima (2008), the service companies already have the largest marketshare in developed countries and many developing countries. This matter, developed through this research, involves shareholders, applying a semi-structured interview. The information obtained was compared with theoretical models, trying to corroborate the basic hypothesis that the strategy adopted has close ties with the view adopted by the international entrepreneurs

Evaluation of Genotoxic, Cytotoxic and Effect on Cell Cycle of Extracts Isolated from three species of Marine Sponges from Urabá´s Gulf

Los organismos marinos han sido reportados como una fuente de compuestos biológicamente activos comparados con los aislados de la superficie terrestre. Dentro de los animales marinos las esponjas son una de las más importantes fuentes de nuevos compuestos con diferentes tipos de actividades biológicas. En este estudio, se evaluaron extractos de tres esponjas marinas procedentes del Golfo de Urabá Colombiano con el fin de evaluar sus potenciales genotóxico, citotóxico y antiproliferativo en dos líneas celulares una de hámster (CHO-K1) y otra humana derivada de cáncer (Jurkat). Se analizaron extractos de diferentes polaridades de las esponjas Amphimedon compressa, Iotrochota birotulata y Myrmekioderma gyroderma. Se encontró que el extracto metanólico de la esponja A. compressa mostró un efecto promisorio a una IC50 de 12μg/ml. Adicionalmente se demostró que su efecto estaba relacionado con alteraciones en el ADN además de influir en la progresión del ciclo celular./Abstract.Marine organisms have been reported as a rich source of biologically active compounds, even more than those living on earth. Among marine animals, sponges are one of the most prominent sources of new compounds with different types of biological activities. In this study, we tested extracts from three Colombian marine sponges from the Uraba Golf aiming to evaluate their cytotoxic, genotoxic and anti-proliferative effects on cultured cells lines (hamster CHO-K1 and human leukemia Jurkat cells). We analyzed extracts of different polarities from Amphimedon compressa, Iotrochota birotulata and Myrmekioderma gyroderma sponges. We found that the methanolic extract from A. compressa sponge showed a promissory cytotoxic effect, with an IC50 of 12μg/ml. Additionally, we demonstrate that its cytotoxic effect is related with alterations in DNA and cell cycle progression.Abstract: Marine organisms have been reported as a rich source of biologically active compounds, even more than those living on earth. Among marine animals, sponges are one of the most prominent sources of new compounds with different types of biological activities. In this study, we tested extracts from three Colombian marine sponges from the Uraba Golf aiming to evaluate their cytotoxic, genotoxic and anti-proliferative effects on cultured cells lines (hamster CHO-K1 and human leukemia Jurkat cells). We analyzed extracts of different polarities from Amphimedon compressa, Iotrochota birotulata and Myrmekioderma gyroderma sponges. We found that the methanolic extract from A. compressa sponge showed a promissory cytotoxic effect, with an IC50 of 12µg/ml. Additionally, we demonstrate that its cytotoxic effect is related with alterations in DNA and cell cycle progression.Magister en Ciencias BiotecnologíaMaestrí

Caracterización antigénica de placas del virus tipo A de la fiebre aftosa.

Se determinó el espectro antigénico para conocer el grado de cobertura inmunológica de los virus vacunales y se definió una metodología para establecer los grados de variación antigénica de las cepas actuantes en el campo. Fueron tomadas 6 cepas del virus tipo A de diferentes regiones del país: A24 Boyacá/71-6000, A27 Guajira/71-6304, A24 Sabanas/74-7510, A27 Cundinamarca/75-8046, A Antioquia/76-8381 y A Córdoba/76-8480. Los resultados mostraron que la cepa A24 Boyacá/71-6000 fué estable respecto al componente antigénico. La cepa A27 Guajira/71-6304 presentó características antigénicas estables en todos los clones aislados. La cepa A24 Sabana/174-7510 mostró características antigénicas similares con alta especificidad frente al suero homólogo de cepa y un considerable grado de fijación con el suero del subtipo A24. Para la cepa A27 Cundinamarca/75-8046, se observó alto grado de identidad antigénica con el subtipo A27. En el caso de la cepa A Antioquia/76-8381 las poblaciones virales de los clones tomados presentaron altas relaciones antigénicas con los sueros de los subtipos A24 y A Sabana/74. Los estudios aplicados a la cepa A Córdoba/76-8480 mostraron poblaciones antigénicas variables. Se concluye que a nivel de campo existen varias cepas virales del tipo A relacionadas antigénicamente con diferentes subtipos, lo cual exige mantener una vigilancia permanente de las características de las cepas utilizadas en vacunas, frente a nuevas cepas aisladas en el campo, aplicando parámetros inmunológicosGanado de doble propósito-Ganaderia doble proposit