The Optimized Model of Multiple Invasion Percolation

We study the optimized version of the multiple invasion percolation model. Some topological aspects as the behavior of the acceptance profile, coordination number and vertex type abundance were investigated and compared to those of the ordinary invasion. Our results indicate that the clusters show a very high degree of connectivity, spoiling the usual nodes-links-blobs geometrical picture.Comment: LaTeX file, 6 pages, 2 ps figure

Short-time critical dynamics of the Baxter-Wu model

We study the early time behavior of the Baxter-Wu model, an Ising model with three-spin interactions on a triangular lattice. Our estimates for the dynamic exponent $z$ are compatible with results recently obtained for two models which belong to the same universality class of the Baxter-Wu model: the two-dimensional four-state Potts model and the Ising model with three-spin interactions in one direction. However, our estimates for the dynamic exponent $\theta$ of the Baxter-Wu model are completely different from the values obtained for those models. This discrepancy could be related to the absence of a marginal operator in the Baxter-Wu model.Comment: 7 pages, 11 figures, accepted for publication in Phys. Rev.

Editorial

Continuamos em tempos de comemoração em nossa Revista. O Centro de Estudos e Pesquisas de Direito Sanitário — CEPEDISA acaba de completar seu vigésimo aniversário. O CEPEDISA nasceu da ambição de alguns professores, pesquisadores e profissionais das áreas da saúde e do direito em desenvolver e divulgar esse novo campo do conhecimento científico. Teve caráter internacional desde sua origem, pois sua primeira atividade foi a realização de um Seminário Internacional sobre o ensino do Direito Sanitário, que avaliou a experiência da Itália, dos Estados Unidos da América e da França no tratamento do tema