Compressed k2-Triples for Full-In-Memory RDF Engines

Current "data deluge" has flooded the Web of Data with very large RDF datasets. They are hosted and queried through SPARQL endpoints which act as nodes of a semantic net built on the principles of the Linked Data project. Although this is a realistic philosophy for global data publishing, its query performance is diminished when the RDF engines (behind the endpoints) manage these huge datasets. Their indexes cannot be fully loaded in main memory, hence these systems need to perform slow disk accesses to solve SPARQL queries. This paper addresses this problem by a compact indexed RDF structure (called k2-triples) applying compact k2-tree structures to the well-known vertical-partitioning technique. It obtains an ultra-compressed representation of large RDF graphs and allows SPARQL queries to be full-in-memory performed without decompression. We show that k2-triples clearly outperforms state-of-the-art compressibility and traditional vertical-partitioning query resolution, remaining very competitive with multi-index solutions.Comment: In Proc. of AMCIS'201

Radiative corrections to all charge assignments of heavy quark baryon semileptonic decays

In semileptonic decays of spin-1/2 baryons containing heavy quarks up to six charge assignments for the baryons and lepton are possible. We show that the radiative corrections to four of these possibilities can be directly obtained from the final results of the two possibilities previously studied. There is no need to recalculate integrals over virtual or real photon momentum or any traces.Comment: 15 pages, 2 figures, RevTex. Extended discussion. Final version to appear in Physical Review

Formulación de un material de impresión dental en forma de pasta

Los materiales de impresión dental (MID) basados en alginato son muy empleados en Estomatología. En la actualidad se plantea que los MID en forma de pasta tienen una mayor fidelidad de copia, mejor reproducción de detalles de la impresión y no desprenden polvos volátiles secos que sean inhalados por los especialistas en su utilización cotidiana, por lo que se decidimos estudiar una formulación de un MID en forma de pasta. En el presente trabajo se reporta un material formado por dos pastas que al mezclarse entre si en las proporciones adecuadas, gelifica, obteniéndose la impresión. En el componente A esta contenido el alginato de sodio, y en el otro componente B, una sal de un metal divalente (CaSO 4). Se utilizó alginato de sodio sin secar, determinando el porciento de humedad y calculando así, el peso de alginato seco. Se agregó al alginato húmedo el resto de los componentes de la pasta A. A la formulación obtenida se le realizaron las siguientes pruebas físico-mecánicas: apariencia y uniformidad, tiempo de trabajo, tiempo de mezcla, tiempo de fraguado, viscosidad, relación pasta A/pasta B, resultando en todos los casos dentro de los límites establecidos según la norma ISO 1563. Se realizó además el ensayo de pérdida de agua del material (sinéresis) y se comparó con el Dentalgin, MID en forma de polvo.Peer Reviewe

Development and characterization of new microsatellite markers for grape

Thirty five new grape microsatellite markers were developed under an international consortium involving AGROGENE. These loci were amplified in 41 Spanish cultivars of V. vinifera. Eleven of the markers were polymorphic and informative in V. vinifera. Twelve were monomorphic and of the remaining markers one was polymorphic but less useful because individuals amplified more than two bands and the rest had amplification problems. The number of alleles detected for the 11 informative markers ranged from 4 to 12, with heterozygosity values ranging from 0.6 to 0.8. Primer sequences are reported for these markers.