I am a lecturer in mathematics at University of Twente in the Netherlands. My research lies in the areas of probability theory, enumerative combinatorics, representation theory on symmetric groups, and analytic number theory. In probability theory and enumerative combinatorics my reseach has evolved around problems related to pattern avoiding permutations, card shuffling problems as well as random labellings on graphs. In analytic number theory my work involves representations of integers by quadratic forms, Theta function identities, determining the number of solutions of quadratic equations, and reciprocity laws for the Legendre symbol.