Understanding how institutional changes within academia may affect the overall potential of science requires a better quantitative representation of how careers evolve over time. Since knowledge spillovers, cumulative advantage, competition, and collaboration are distinctive features of the...

Complex systems can be characterized by classes of equivalency of their elements defined according to system specific rules. We propose a generalized preferential attachment model to describe the class size distribution. The model postulates preferential growth of the existing classes and the...

Objective: To describe the changes in costs of care for HIV - positive patients in Italy after the spread of antiretroviral combination therapies (HAART). Methods: Five thousand four hundred and twenty - two patients from the I.CO.N.A. (Italian Cohort Naive Antiretrovirals) study were followed...