Mixed QCD and Weak Corrections to $t\bar{t}$ Production by   Quark-Antiquark Annihilation
  We report on our computation of the mixed QCD and weak corrections to $q {\bar q} \to t\bar{t}$ including $t, \bar t$ spin effects, in particular on single top spin asymmetries. 
W. Bernreuther, M. Fuecker, Z. G. Si