- 1911-1911
Research Associate, Wisconsin Institute of Medical Research, Wisconsin University, Madison, Wisconsin, USA, ويست كونسنت, امــريــكـا
- 2001-2002
Junior Research Fellow, Dept. of zoology. Lalit Narayan Mithila University University, Darbhanga, الهــــــند
- 2002-2005
Junior Research Fellow , special Centre for Molecular Medicine, Darbhnga, الهــــــند
- 2005-2008
Senior Research Fellow , Jawaharlal Nehru University, نيودلهي, الهــــــند
- 2009-2011
Post Doctoral Fellow, Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, KS, USA., كنساس, امــريــكـا