Comparing EQP and MOD_{p^k}P using Polynomial Degree Lower Bounds
  We show that an oracle A that contains either 1/4 or 3/4 of all strings of length n can be used to separate EQP from the counting classes MOD_{p^k}P. Our proof makes use of the degree of a representing polynomial over the finite field of size p^k. We show a linear lower bound on the degree of this polynomial.   We also show an upper bound of O(n^{1/log_p m}) on the degree over the ring of integers modulo m, whenever m is a squarefree composite with largest prime factor p. 
M. de Graaf (CWI, Amsterdam) and P. Valiant (Stanford)