Effective restoration of chiral and axial symmetries at finite temperature and density

The effective restoration of chiral and axial symmetries is investigated within the framework of the SU(3) Nambu Jona-Lasinio model. The topological susceptibility, modelled from lattice data at finite temperature, is used to extract the temperature dependence of the coupling strength of the anomaly. The study of the scalar and pseudoscalar mixing angles is performed in order to discuss the evolution of the flavour combinations of q \skew2\bar{q} pairs and its consequences for the degeneracy of chiral partners. A similar study at zero temperature and finite density is also realized.