Subharmonicity of the modulus of quasiregular harmonic mappings

In this note we determine all numbers $q\in \mathbf{R}$ such that $\mathrm{\mid }u{\mathrm{\mid }}^q$ is a subharmonic function, provided that $u$ is a $K-$quasiregular harmonic mappings in an open subset $\mathrm{\Omega }$ of the Euclidean space ${\mathbf{R}}^n$.