2005-present Senior Associate Dean Research and Graduate Studies Virginia-Maryland College of Veterinary Medicine Virginia Tech Blacksburg, VA, USA 2002 Interim Vice Provost for Graduate Studies and Dean Graduate School, Virginia Tech Blacksburg, VA, USA 1999-2005 Senior Associate Dean Graduate School, Virginia Tech Blacksburg, VA, USA 1986-1999 Chairman and Professor of Virology Department of Microbiology and Immunology College of Veterinary Medicine, Cornell University Ithaca, New York, USA 1984-1986 Head of Department of Microbiology Institute for Animal Health, Houghton Laboratory Houghton, Cambridgeshire, UK 1983-1984 Professor of Virology & Director of Virology Section Department of Veterinary Molecular Biology Adjunct Professor of Microbiology Department of Microbiology Montana State University Bozeman, Montana, USA 1980-1982 Senior Lecturer (Associate Professor) in Biological Sciences University of Warwick Coventry, UK 1978 Visiting Fellow Amyotrophic Lateral Sclerosis Foundation Inc. Torrey Pines Research Center San Diego, California, USA 1975 Visiting Medical Research Council Fellow in Cancer Studies University of California Medical Center San Francisco, California, USA 1971-1980 Lecturer (Assistant Professor) in Biological Sciences University of Warwick Coventry, UK 1969-1971 Postdoctoral Research Fellow of the Carnegie Institution Washington, D.C., USA