Universal Strangeness Production in Hadronic and Nuclear Collisions
  We show that strangeness suppression in hadronic and nuclear collisions is fully determined by the initial energy density of the collision. The suppression factor $\gamma_s(s)$, with $\sqrt s$ denoting the collision energy, can be expressed as a universal function of the initial energy density $\epsilon_0(s)$, and the resulting pattern is in excellent agreement with data from $p-p,~p-Pb,~Cu-Cu,~Au-Au$ and $Pb-Pb$ data over a wide range of energies and for different centralities. 
P.Castorina, S.Plumari, H.Satz
hep-ph nucl-th