Groebner bases, monomial group actions, and the Cox rings of Del Pezzo   surfaces
  We introduce the notion of monomial group action and study some of its consequences for Groebner basis theory. As an application we prove a conjecture of V. Batyrev and O. Popov describing the Cox rings of Del Pezzo surfaces (of degree at least 3) as quotients of a polynomial ring by an ideal generated by quadrics. 
Mike Stillman, Damiano Testa, Mauricio Velasco