  The single vortex problem in a strongly correlated bosonic system is
investigated self-consistently within the mean-field theory of the Bose-Hubbard
model. Near the superfluid-Mott transition, the vortex core has a tendency
toward the Mott-insulating phase, with the core particle density approaching
the nearest commensurate value. If the nearest neighbor repulsion exists, the
charge density wave order may develop locally in the core. The evolution of the
vortex configuration from the strong to weak coupling regions is studied. This
phenomenon can be observed in systems of rotating ultra-cold atoms in optical
lattices and Josephson junction arrays
