Further remarks on the elementary theory of formal power series rings -- Elimination of quantifiers for non semi-simple rings of characteristic p -- The quantifier elimination problem for rings without nilpotent elements and for semi-simple rings -- Existentially closed modules: Types and prime models -- Rings of continuous functions: Decision problems -- Weak partition relations, finite games, and independence results in Peano arithmetic -- Hensel fields in equal characteristic p>0 -- On polynomials over real closed rings -- Les corps faiblement algebriquement clos non separablement clos ont la propriete d'independance -- Horn-theories of abelian groups -- Two orderings of the class of all countable models of peano arithmetic -- Ramsey quantifiers in arithmetic -- Computational complexity of decision problems in elementary number theory -- Some diophantine nullstellensätze -- A tree analysis of unprovable combinatorial statements -- A hierarchy of cuts in models of arithmetic -- Cofinal extension preserves recursive saturation -- Some model theory and number theory for models of weak systems of arithmetic -- Applications of complexity theory to ?o-definability Problems in arithmetic -- Minimally saturated models -- Totally categorical theories: Structural properties and the non-finite axiomatizability.