Here are computer transparencies for talks I have given (since 2007)

Generating functions for lattice points on polytopes versions of this talk have been presented at IBM research, IMA, Klagenfurt Austria, Univ. British Columbia, TU Berlin.

Easy-to-state but-hard-to-solve problems on convex polytopes versions of this talk have been presented at MAA mathfest, Sonoma State Univ. and SACNAS meeting.

Algebraic techniques in Optimization versions of this talk have been presented at Rice University, IMA.

Transportation polytopes: A 20 years updateversions of this talk have been presented at MIT Operations Research seminar, Lisbon University, DMV meeting Mainz.

Hilbert's Nullstellensatz and Combinatorial feasibility versions of this talk have been presented at MIT's Combinatorics seminar, Tilburg University, TU Berlin, Magdeburg University

I presented a fresh updated longer new version at 4ICC in New Zealand

Integration of Polynomials over polytopes versions of this talk have been presented at Oberwolfach, MAA sectional meeting Sacramento

Algebraic Combinatorics and Geometry influence Discrete Optimization versions of this talk have been presented at Montreal and at Berkeley.

Geometria combinatoria de cuadrados m\'agicos, latinos, sudokus, y otras tablas curiosas In spanish presentation for Colloquium Victor Neumann-Lara.

Top coefficients of the Sylvester Denumerant versions of this talk have been presented at the joint math meetings in San Diego 2013

Recent Advances in the Theory of Linear Optimization . This talk has been presented at several venues, including AMS Boulder, Caltech, Freie Univ. Berlin, and Univ. Magdeburg in Germany. You can watch a video of the Magdeburg lecture .