Agradecimentos: The editors express their sincere thanks to Magnifico Reitor of the Universidade Estadual de Campinas, Prof. José Aristodemo Pinotti who put at our disposal all the human and material resources needed through the editor of Unicamp, Prof. Jaime Pinsky, to make possible the publication of the Festschrift volume. The editors also thank all scientists who sent in their original scientific contributions and participated in this festive occasion. Lastly, but for the support of the administrative personnel, in particular Miss Sandra Fonseca and Miss Marilena Aparecida Borelli who worked extensively on retyping the various contributed articles, this volume would not have been completed. To them, we owe our many thanks Ver menos