  We consider the (3+1) dimensional expansion and cooling of the
chirally-restored and deconfined matter at finite net-baryon densities as
expected in heavy-ion collisions at moderate energies. In our approach, we
consider chiral fields and the Polyakov loop as dynamical variables coupled to
a medium represented by a quark-antiquark fluid. The interaction between the
fields and the fluid leads to dissipation and noise, which in turn affect the
field fluctuations. We demonstrate how inhomogeneities in the net-baryon
density may form during an evolution through the spinodal region of the
first-order phase transition. For comparison, the dynamics of transition
through the crossover and critical end point is also considered.
