Harassment Origin for Kinematic Substructures in Dwarf Elliptical   Galaxies?
  We have run high resolution N-body models simulating the encounter of a dwarf galaxy with a bright elliptical galaxy. The dwarf absorbs orbital angular momentum and shows counter-rotating features in the external regions of the galaxy. To explain the core-envelope kinematic decoupling observed in some dwarf galaxies in high-density environments requires nearly head-on collisions and very little dark matter bound to the dwarf. These kinematic structures appear under rather restrictive conditions. As a consequence, in a cluster like Virgo ~1% of dwarf galaxies may present counter-rotation formed by harassment. 
A. C. Gonzalez-Garcia, J. A. L. Aguerri, M. Balcells (Instituto de   Astrofisica de Canarias)