Résumé. Les entrepôts de données XML proposent une base intéressante pour les applications décisionnelles qui exploitent des données hétérogènes et provenant de sources multiples. Cependant, les performances des SGBD natifs XML étant actuellement limitées en termes de temps de réponse et de volume des données, il est nécessaire de trouver des moyens pour les optimiser. Dans cet article, nous pr...

We consider a polymerization (fragmentation) model with size-dependent parameters involved in prion proliferation. Using power laws for the different rates of this model, we recover the shape of the polymerization rate using experimental data. The technique used is inspired from [30], where the fragmentation dependence on prion strains is investigated. Our improvement is to use power laws for t...

We report the recent progress in the studies of D-wave heavy quarkonia production from gluon fragmentation at the Tevatron and in Z decays, and the D-wave charmonia production in B decays. We show that the color-octet contributions are of crucial importance to the production of D-wave quarkonia. Signals, as strong as that for J/ψ and ψ′, should be seen for the D-wave charmonium in the processes...

Transversely polarized Λ production in hard scattering processes is discussed in terms of a leading twist T-odd fragmentation function which describes the fragmentation of an unpolarized quark into a transversely polarized Λ. We focus on the properties of this function and its relevance for the RHIC and HERMES experiments.