Listar Articulos, Pre-prints (Facultad de Ciencias) por título

Mostrando ítems 324-343 de 488

    • O caso das savanas tropicais da América do Sul: quando a sustentabilidade econômica e ecológica não é suficiente 

      Sarmiento, Guillermo; Pinillos, Marcela (2006)
      O caso das savanas tropicais da América do Sul ilustra as complexas interrelações entre as características ecológicas dos ecossistemas terrestres naturais e os seus usos. As savanas tropicais estão determinadas por um ...

    • On duality in the born-infeld theory 

      Khoudeir, Adel; Parra, Yoan (SABER ULA, 2005-01-06)
      On duality in the born-infeld theory (Khoudeir, Adel; Parra, Yoan) Abstract The SL(2,R) duality symmetric action for the Born-Infeld theory in terms of two potentials, coupled with non-trivial backgroud fields in ...

    • On supersymmetry at high temperature 

      Melfo, Alejandra; Senjanovic, Goran; Bajc, Borut (SABER ULA, 2005-01-06)
      On supersymmetry at high temperature (Melfo, Alejandra; Bajc, Borut; Senjanovic, Goran) Abstract While it is possible to find examples of field theories with a spontaneously broken symmetry at high temperature, in ...

    • On the collineations of distribution-valued Ricci tensor fields of domain wall spacetimes. 

      Pantoja, Nelson; Sanoja, Alberto (SABER ULA, 2007-03-27)
      On the collineations of distribution-valued Ricci tensor fields of domain wall spacetimes. (Pantoja, Nelson y Sanoja, Alberto) Abstract Generalizing the Lie derivative to distribution-valued tensors, we examine the ...

    • On the definition of cylindrical symmetry 

      Carot, Jaume; Senovilla, José M. M.; Vera, Raül (SABER ULA, 2008-07-02)
      On the definition of cylindrical symmetry (Carot, Jaume; Senovilla, José M. M.; Vera, Raül) Abstract The standard definition of cylindrical symmetry in general relativity is reviewed. Taking the view that axial ...

    • On the eccentricity behaviour of radiating slowly rotating bodies in general relativity 

      Núñez, Luis; Herrera Cometta, Luis; Percoco, Umberto; Hernández G., Héctor (SABER ULA, 2006-01-26)
      On the eccentricity behaviour of radiating slowly rotating bodies (Núñez, Luis; Hernández, Hector; Herrera, Luis; Percoco, Umberto) Abstract We study different models of radiating slowly rotating bodies up to the ...

    • On the general structure of Ricci collineations for type B warped spacetimes. 

      Flores, J. L.; Percoco, Umberto; Parra, Yoan (SABER ULA, 2005-08-18)
      On the general structure of Ricci collineations for type B warped spacetimes (Flores, J. L.; Parra, Yoan; Percoco, Umberto.) Abstract A complete study of the structure of Ricci collineations for type B warped spacetimes ...

    • On the geometry of warped spacetimes 

      Carot, Jaume; da Costa, J. (SABER ULA, 2008-07-02)
      On the geometry of warped spacetimes (Carot, Jaume; da Costa, J.) Abstract An invariant characterization of warped spacetimes is given and a classification scheme for them is proposed. Some results on the curvature ...

    • On the spontaneous break down of massive gravities in 2+1 dimensions 

      Khoudeir, Adel; Aragone, Carlos; Arias, Pío José (SABER ULA, 2005-01-06)
      On the spontaneous break down of massive gravities in 2+1 dimensions (Khoudeir, Adel; Aragone, Carlos; Pío José, Arias) Abstract We show that locally Lorentz invariant, third order, topological massive gravity can ...

    • Operating water cherenkov detectors in high altitude sites for the large aperture GRB observatory 

      Allard, D.; Alvarez, C.; Asorey, H.; Barros, Humberto J. V.; Bertou, Xavier; Castillo, M.; Chirinos, J. M.; De Castro, A.; Flores, S.; González, J.; Gomez Berisso, M.; Grajales, J.; Guada B., Carlos E.; W.R. Guevara, Day; Ishitsuka, J.; López, J. A.; Martínez, O.; Melfo, A.; Mezal, E.; Miranda Loza, P.; Moreno Barbosa, E.; Murrugarra, C.; Núñez, Luis; Otiniano Ormachea, L. J.; Pérez, G.; Pérez, Y.; Ponce, E.; Quispe, J.; Quintero, Carlos; Rivera, H.; Rosales R., Misael D.; Rovero, A. C.; Saavedra, O.; Salazare, H.; Tello, J. C.; Ticona Peraldam, R.; Varela, E.; Velarde, A.; Villasenor, L.; Wahl, D.; Zamalloa, M. A. (http://arxiv.org/, Polonia, 2009-06-04)
      Water Cherenkov Detectors (WCD) are efficient detectors for detecting GRBs in the 10 GeV - 1 TeV energy range using the single particle technique, given their sensitivity to low energy secondary photons produced by high ...

    • Optimization of Benzoxazinones as natural herbicide models by Lipophilicity enhancement. 

      Macías, Francisco A.; Marín, David; Oliveros Bastidas, Alberto; Molinillo G., José (SABER ULA, 2007-04-09)
      Optimization of Benzoxazinones as natural herbicide models by Lipophilicity Enhancement. (Macías, Francisco A.; Marín, David; Oliveros Bastidas, Alberto y Molinillo G., José Abstract Benzoxazinones are plant allelochemicals ...

    • Optimum phase-behavior formulation of surfactant/oil/water systems for the determination of chromium in heavy crude oil and in bitumen-in-water emulsion 

      Burguera, José Luis; Pascu de Burguera, Marcela; Burguera Pascu, Constantin R.; Ávila G., Rita M.; Salager, Jean Louis; Bracho P., Carlos L.; Antón, Raquel E.; Burguera Pascu, Margarita; Brunetto, Rosario; Gallignani, Maximo A.; Petit de P., Yaneira (SABER ULA, 2006-02-01)
      Optimum phase-behavior formulation of surfactant/oil/water systems for the determination of chromium in heavy crude oil and in bitumen-in-water emulsion. (Burguera, José L.; Ávila G., Rita M.; Pascu de Burguera, Marcela; ...

    • Padrões fitogeográficos e sus relação com sistemas de terra no bioma cerrado 

      Felfili, J. M.; Felfili, Maria; Nogueira, Paul; Silva Armas, Juan F.; Fariñas G, Mario R.; Nunes, Marcelo; Da Silva, Manoel; Rezende, Alba; William, Chistopher (Matiko, S., Pedrosa de Almeida, S. y J.F. Ribeiro (Eds). Cerrado: Ecología e flora.Vol 1. EMBRAPA, BrasiL, pp. 213-228., Brasil, 2008)

    • Los paisajes sismicos. 

      Laffaille, Jaime R. (SABER ULA, 2007-06-04)

    • Parecen lejanos los tsunamis de Asia... 

      Laffaille, Jaime R. (SABER ULA, 2007-06-04)

    • Participatory planning for biodiversity conservation in the high tropical andes: are farmers interested? 

      Llambí, Luis Daniel; Smith, Julia K.; Pereira Colls, Nory Beatriz; Pereira, Ana Carlota; Valero, Francis; Monasterio, Maximina; Dávila, María Vicenta (2005)
      The success of participatory conservation projects depends greatly on the interest shown by the local population and on the strategies used to incorporate all stakeholders from the initial stages. In the highly diverse ...

    • Patrones de vientos troposféricos en la cuenca del Lago de Maracaibo, Venezuela. 

      López, Jorge; Andressen L., Rigoberto; Lugo, Arnaldo (Venezuela, 2010)
      Se estudió el patrón de vientos en la baja tropósfera, en los sectores meridional y oriental de la cuenca del Lago de Maracaibo utilizando globospilotos, durante el período abril-mayo de 2004. Los lanzamientos se hicieron ...

    • Páramos 

      Azócar, Aura; Fariñas G, Mario R. (2003)

    • Pesquisa serológica y molecular de Brucella sp. en un rebaño bufalino lechero en la Cuenca del Sur del Lago de Maracaibo 

      Rosales Zambrano, Datty; Ángela Lugo; Andueza Leal, Félix Daniel; López Merino, Ahidé; Morales Estrada, Aurea; Bolívar Sánchez, Ana María (Venezuela, 2015)
      En el siguiente estudio se presentan los resultados de un protocolo de diagnóstico de Brucelosis bovina, en una finca lechera bufalina (Bubalus bubalis) con problemas reproductivos. Un rebaño total de 80 búfalos se sometió ...

    • Phenolics and condensed tannins in relation to altitude in neotropical Pteridium spp. 

      Oliveros Bastidas, Alberto; Alonso Amelot, Miguel; Calcagno P., María Pía (SABER ULA, 2005-07-01)
      Phenolics and condensed tannins in relation to altitude in neotropical Pteridium spp. A field study in the Venezuelan Andes (Alonso Amelot, Miguel; Oliveros, Alberto and Calcagno Pisarelli, María Pía) Abstract Two ...