Canadian Applied and Industrial Mathematics Annual Meeting, Fields Institute, Toronto, Canada, June 24-28, 2012 (lecturer).
Rocky Mountain Mathematics Consortium Summer School 2012, Mathematical Modeling in Ecology and Epidemiology, University of Wyoming, Laramie, Wyoming, June 11-22, 2012 (lecturer).
Mathematical Innovative Methods and Models of BIOsciences, University of Trent, Trento, Italy, December 19-21, 2011 (organizer and invited speaker).
Exploratory Workshop on Emerging Infectious Diseases and Mathematical Modelling, Centre de Recerca Matematica, Bellaterra, Barcelona, Spain, July 11-15, 2011 (invited speaker).
Partial Differential Equations and Applications, Laboratoire de Mathematiques et Applications, University of Poitiers, Poitiers, France, June 10, 2011.
10th Red Raider Mini-Symposium, Mathematical Modeling in Population Biology and Epidemiology, Texas Tech University, Lubbock, Texas, October 28-29, 2010 (invited speaker).
CMPD3 Computational and Mathematical Population Dynamics, University of Bordeaux, Bordeaux, France, May 31-June 4, 2010 (contributing speaker).
White Workshop on Mathematical Biology, University of Trent, Trento, Italy, December 17-19, 2009 (plenary speaker).
19th Annual Meeting of the Japanese Society for Mathematical Biology, University of Tokyo, Tokyo, Japan, September11, 2009 (plenary speaker).
Mathematics of Influenza: Models for the Transmission Dynamics and Control of Seasonal and Pandemic Flu Outbreaks, SIAM Annual Meeting, Denver, Colorado, July 9,10, 2009 (invited speaker).
Mathematical Modeling in the Medical Sciences, 24th Annual Shanks Lectures, Vanderbilt University, Nashville, Tennessee, May 18-21, 2009 (organizer).
Conference on Differential Equations and Applications in Ecology and Epidemiology, Purdue University, West Lafayette, Indiana, December 8-10, 2008 (invited speaker).
Workshop on the Growth and Control of Tumors: Theory and Experiment, Fields Institute, Toronto, Canada, July 2-4, 2008 (invited speaker).
Conference on Differential Equations and Applications to Mathematical Biology, University of Le Havre, Le Havre, France, June 23-27, 2008 (plenary speaker).
Workshop on Population Dynamics and Mathematical Biology, Centre International Rencontres Mathematiques, Luminy, France, June 16-20 2008 (plenary speaker).
Atlantic Coast Symposium on the Mathematical Sciences in Biology and Biomedicine, North Carolina State University, Raleigh, North Carolina, April 24-26, 2008 (plenary speaker).
American Association for the Advancement of Science, Annual Meeting, Boston, MA, Special Session on Modeling the dynamics of the drug-resistant killers of the 21st century, February 17, 2008 (invited speaker).
Seventh Mississippi State – University of Alabama at Birmingham Conference on Differential Equations & Computational Simulations, Birmingham, AL, November 2-3, 2007 (invited speaker).
Vanderbilt Integrative Cancer Biology Center 3rd Annual Workshop, Mathematical Modeling and Clinical Oncology:The Road to Convergence, Vanderbilt University, Nashville, TN, July 15-19, 2007 (invited speaker).
Conference on Frontiers in Applied and Computational Mathematics, New Jersey Institute of Technology, Newark, NJ, May 14-16, 2007 (invited speaker).
Mathematical Association of America Undergraduate Research Conference, University of Tennessee, Knoxville, TN, April 14, 2007 (guest speaker).
Bridging the scales of disease dynamics 2006, University of British Columbia, Vancouver, Canada, September 27-29, 2006 (invited speaker).
Vanderbilt Integrative Cancer Biology Center Annual Workshop, Building Mathematical Models of Cancer Across Biological Scales, Vanderbilt University, Nashville, TN, July 18-21, 2006
Workshop on Mathematical Models in Biology and Medicine, February 3-4, 2006, Arizona State University (keynote speaker).
Vanderbilt Integrative Cancer Biology Center 1st Annual Workshop, Mathematical Modeling in Cancer Biology, Vanderbilt University, Nashville, TN, August 8-12, 2005 (invited lecturer).
Control Theory with Modeling Applications to Physiology and Medicine, Summer School in Graz, July 24th- August 5th, 2005 (invited speaker).
International Workshop on Differential Equations in Mathematical Biology, University of Le Havre, Le Havre, France, July 11-13, 2005 (organizer and speaker).
Mathematical Modeling, Implications for Pandemic Influenza Preparedness Workshop, MITACS, Public Health Agency Canada, British Columbia Centre for Disease Control, Vancouver, Canada, March 30-31, 2005, invited speaker.
Workshop on Modeling the Rapid Evolution of Infectious Diseases: Epidemiology and Treatment Strategies, Fields Institute, University of Western Ontario, London, Canada, May 14-17, 2005, organizer.
John Neuberger Conference, University of North Texas , Denton , Texas , October 30-31, 2004 , invited speaker.
American Mathematical Society Sectional Meeting, Vanderbilt University , Nashville , Tennessee , October 16-17, 2004, (speaker and organizer of the Special Session on Mathematical Biology).
International Conference on Nonlinear Dynamics and Evolution Equations, Memorial University of Newfoundland , St. John’s , Newfoundland , Canada , July 6-10, 2004 (plenary speaker).
Computational and Mathematical Population Dynamics, University of Trent , Trento , Italy , June 21-25, 2004 .
Joint Meeting of the American Mathematical Society and Sociedad Matemática Mexicana, Special Session on Continuous Distributed Parameters Models in Mathematical Biology, Houston , Texas , May 13-15, 2004 (invited speaker).
Workshop on Immunology Models, Mathematical Biosciences Institute, Ohio State University, Columbus, Ohio, May 10-14, 2004 .
American Mathematical Society Sectional Meeting, Florida State University, Tallahassee , Florida , March 12-13, 2004 (invited address).
American Mathematical Society Sectional Meeting, University of North Carolina , Chapel Hill , North Carolina , October 25, 2003, (speaker and organizer of the Special Session on Mathematical Models in Medicine).
Workshop on Biodefense, Institute for Mathematics and its Applications, University of Minnesota , Minneapolis , Minnesota , September 28, 2002 (invited speaker).
Beijing University of Science and Technology, Beijing, China, August 12. 2002 (invited colloquium speaker).
International Congress of Mathematicians Satellite Conference on Mathematical Biology, Guilin , China , August 15-18, 2002 (plenary speaker).
Conference on Mathematical Modeling of Population Dynamics, Bedlewo , Poland , June 24-28. 2002 (invited speaker).
School on Population Dynamics, Bedlewo , Poland , June 17-22, 2002 (invited lecturer).
International Conference on Computation Mathematics and Modeling, Bangkok , Thailand , May 22-24, 2002 (plenary speaker).
Workshop on Mathematical Models of Cancer, Vanderbilt University, Nashville, Tennessee, May 3-5, 2002 (organizer).
First SIAM Conference on the Life Sciences, Boston , Massachusetts , March 6-8, 2002 (plenary speaker).
Southeast Conference on Applied Mathematics, North Carolina State University, Raleigh, North Carolina, November 8-11, 2001 (invited speaker).
European Society of Mathematical and Theoretical Biology, School on Biology and Mathematics of Cells, Siguenza , Spain , June 15-22, 2001 (invited lecturer).
Amer. Math. Soc. Annual Meeting, Special Session on Partial Differential Equations in Population Biology and Epidemics, New Orleans , Louisiana , January 10-11. 2001.
Evolution Equations 2000: Applications to Physics, Industry, Life Sciences and Economics, Trento , Italy , October 30 - November 4, 2000 (invited speaker).
Second International Conference on Deterministic and Stochastic Modeling of Biointeractions, Purdue University , August 23 -27, 2000 (invited speaker).
Society of Mathematical Biology Annual Meeting, University of Utah , Salt Lake City , Utah , August 3-5, 2000 (invited speaker).
Southeastern Atlantic Regional Conference on Differential Equations, University of Richmond, Richmond, Virginia, October 22-23, 1999 (plenary speaker).
Annual Meeting of the Genetics Society of Japan, University of Hiroshima , Hiroshima , Japan , September 24-26, 1999 (invited speaker).
Second Summer School in Mathematical Biology, Termoli , Italy , June 12-19, 1999 (invited lecturer).
Workshop on Mathematical Approaches for Emerging and Reemerging Infectious Diseases, Institute for Mathematics and its Applications, University of Minnesota , May 17-21, 1999 (invited speaker).
Workshop on the Dynamics and Control of AIDS, Institute for Mathematics and its Applications, University of Minnesota , November 7-10, 1998 (invited speaker).
Conference on Asymptotic Properties of Evolution Equations, The Banach Center, Warsaw , Poland , June 29 - July 3, 1998 (invited speaker).
Fifth International Conference on Mathematical Population Dynamics, Zakopane, Poland, June 21-26, 1998 (organizer and speaker in the Special Session on Cancer Diagnosis and Therapy and speaker in the Special Session on Viral and Cellular Dynamics during HIV Infection).
Population Dynamics Workshop, Chalmers University , Gothenburg , Sweden , May 11-15, 1998 (invited speaker).
Conference on Mathematical and Statistical Models in Health Sciences, University of Memphis , Memphis , Tennessee , March 27-28, 1998 .
Joint Meeting of the Sociedad Matematica Mexicana and the American Mathematical Society, Special Session on Nonlinear Models in Biology , Oaxaca , Mexico , December 4-6, 1997 .
Third Midwest-Southeastern Atlantic Joint Regional Conference on Differential Equations, Vanderbilt University, Nashville, Tennessee, November 7-9, 1997, Organizer.
International Conference on Differential Equations with Applications to Biology, Dalhousie University, Halifax, Nova Scotia, July 25-29, 1997, (Plenary Speaker)
Summer School on Cell Population Dynamics, Saint-Flour , France , June 2-13, 1997 (Lecturer).
Conference on Mathematical Models in Medical and Health Sciences, Vanderbilt University, Nashville, Tennessee, May 28-31, 1997 (organizer).
Conference on Evolution Equations and Their Applications to Technology, Hiroshima , Japan , October 27-31, 1996 (invited speaker).
Society for Mathematical Biology Annual Meeting, University of Washington , Seattle Washington , August 8-13, 1996 .
Conference in Honor of A. Bressan, Universita di Padova, Padua , Italy , May 26-28, 1996 .
Waves and memory in Continua: A meeting in Honor of Richard C. MacCamy, Carnegie-Mellon University, Pittsburgh, Pennsylvania, August 17-19, 1995.
2nd Marrakesh International Conference on Differential Equations, University of Marrakesh, Marrakesh, Morocco, June 16-20, 1995 (plenary speaker).
Fourth International Conference on Mathematical Population Dynamics, Rice University, Houston, Texas, May 23-27, 1995, (plenary speaker).
ICMS Workshop: Chemotherapy Modelling, Heriot-Watt University and Edinburgh University , Edinburgh , Scotland , April 10-14, 1995 (principal speaker).
Evolution Equations and Semigroups, Scuola Normale Superiore di Pisa, Pisa , Italy , September 26 - October 1, 1994 (invited speaker).
Conference on Evolution Equations, University of Strathclyde , Glasgow , Scotland , July 25-29, 1994 (plenary speaker)
International conference on Differential Equations and Applications to Biology and to Industry, Harvey Mudd College , Claremont , California , June 1-4, 1994 (invited speaker).
First World Congress on Computational Medicine and Public Health, University of Texas System Center for High Performance Computing, Austin , Texas , April 24-29, 1994 (invited speaker).
UAB-Georgia Tech International Conference on Mathematical Physics and Differential Equations, University of Alabama at Birmingham, Birmingham, Alabama, March 17, 1994.
Second European Conference on Mathematics Applied to Biology and Medicine, Lyon , France , December 15-17, 1993 (invited speaker).
Regional Meeting of the American Mathematical Society Special Session in Reaction Diffusion Equations, Texas A & M University , College Station , Texas , October 22-28, 1993 (invited speaker).
Society for Mathematical Biology Annual Meeting, Cornell University , Ithaca , New York , July 10-13, 1993 .
Evolution Equations Conference, Louisiana State University , Baton Rouge , Louisiana , January 7-11, 1993 (principal speaker)
Midwest-Southeastern Atlantic Second Joint Regional Conference on Differential Equations, University of Kentucky, Kentucky, November 13- 14, 1992.
World Congress of Nonlinear Analysts, Special Session on Populations of Cells and Genes, Tampa , Florida , August 23-25, (invited speaker)
Third International Conference on Mathematical Population Dynamics, June 1-5, 1992 , University of Pau , Pau , France (plenary speaker)
Georgia Tech - UAB International Conference on Differential Equations and Mathematical Physics, Atlanta , Georgia , March 22-28, 1992 .
Differential Equations in Banach Spaces, Universita di Bologna, Bologna , Italy , July 1-5, 1991 (invited speaker).
UAB Conference on Differential Equations and Mathematical Physics, University of Alabama at Birmingham, Birmingham, Alabama, March 15-20, 1990.
UTK/NSF Conference on Science, Mathematics, and Engineering Education, University of Tennessee, Knoxville, Tennessee, February 2-3, 1990.
International Conference on Differential Equations and Applications to Biology and Population Dynamics, Claremont , California , January 10-13, 1990 (invited speaker).
Ninth Annual Georgia Tech Mathematics Conference, Georgia Tech, Atlanta , Georgia , October 28, 1989 (invited speaker)
Second International Conference on Mathematical Population Dynamics, May 17-20, 1989 , Rutgers University , New Brunswick , New Jersey (invited speaker and organizer)
Special Session on Mathematics in Population Biology, Amer. Math. Soc. Annual Meeting, Jan. 11-14, 1989 , Phoenix , Arizona (invited speaker).
Southeastern-Atlantic Regional Conference on Differential Equations, University of Georgia , November 4-5, 1988 .
Conference on Differential Equations and Population Biology, University of Alberta, Edmonton, Alberta, Canada, June 20-25, 1988.
One-parameter Semigroups and Differential Operators, Mathematisches Forschungsinstitut, Jan. 25-30, 1988 , Oberwolhfach , Germany (invited speaker).
Special Session on Nonlinear Differential-Delay Equations, Amer. Math. Soc. Annual Meeting, Jan. 6-8, 1988 , Atlanta , Georgia (invited speaker).
Combined Midwest -Southeast Differential Equations Conference, Vanderbilt University , Nashville , Tennessee , October 23-24, 1987 (organizer).
Trends in Semigroup Theory and Applications, Universita di Trieste, Triest , Italy , September 28 - October 2, 1987 (invited speaker)
Conference on Mathematical Population Dynamics, The University of Mississippi, Oxford, Mississippi, November 20-22, 1986 (principal speaker).
Southeastern-Atlantic Regional Conference on Differential Equations, Clemson University , October 24-25, 1986 .
Midwest Differential Equations Conference, Marquette University , October 17-18, 1986 (principal speaker).
SIAM 1986 National Meeting, Boston , July 20-25, 1986 .
Southeastern-Atlantic Regional Conference on Differential Equations, Georgia Institute of Technology, October 25-26, 1985 .
Southeastern-Atlantic Regional Conference on Differential Equations, Wake Forest University , October 12-13, 1984 (principal speaker).
International Conference on Operator Semigroups and Applications, Schloss Retzhof , Austria , June 6-11, 1983 ( invited speaker).
Southeastern-Atlantic Regional Conference on Differential Equations, North Carolina State University , October 8-9, 1982 .
10th IMACS Conference on Systems Simulation and Scientific Computing, Montreal , Canada , August 10-12, 1982 .
Southeastern-Atlantic Regional Conference on Differential Equations, Virginia Tech, Blacksburg, VA, November 13-14, 1981.
Conference on Differential Equations and Applications, Schloss Retzhof , Austria , June 2-6, 1981 (invited speaker).
Conference on Differential Equations and Applications to Ecology, Epidemics and Population Problems, Harvey Mudd College, Claremont , California , January 10-11, 1981 (invited speaker)
Workshop on Nonlinear Boundary Value Problems, International Centre for Theoretical Physics, Triest , Italy , June 9-20, 1980 (invited speaker).
Nonlinear Differential Equations: Invariance, Stability, and Bifurcation, Universita di Trento, Trent , Italy , May 25-30, 1980( invited speaker).
Special Session on Linear and Nonlinear Age-dependent models of Population Growth, Amer. Math. Soc. Annual Meeting, Jan. 3-4, 1980 , San Antonio , Texas (invited speaker).
Canadian Mathematical Society Annual Seminar-Functional Differential Equations, University of Toronto , July 30 - August 3, 1979 (invited speaker).
Functional Differential Equations and Integral Equations Conference, West Virginia University , June 18-20, 1979 (invited speaker).
Helsinki Symposium on Integral Equations, Helsinki Institute of Technology, Helsinki , Finland , August 11-14, 1978 (invited speaker).
Symposium on Nonlinear Analysis and Applications, Heriot-Watt University , Edinburgh , Scotland , August 7-10, 1978 (invited speaker).
Symposium on Nonlinear Evolution Equations, University of Wisconsin , October 17-19, 1977 .
Symposium on Nonlinear Equations in Abstract Spaces, University of Texas at Arlington , Arlington , Texas , June 8-10, 1977 (invited speaker).
Conference on Functional Differential Equations, Brown University , May 19-20, 1977 (invited speaker)
Midwest Regional Conference on Differential and Integral Equations, University of Southern Illinois at Carbondale , October 8-9, 1976 (invited speaker).
Conference on Nonlinear Systems and Applications to Life and Physical Sciences, University of Texas at Arlington , Arlington , Texas , July 19-23, 1976 (invited speaker).
National Science Foundation Regional Conference on Nonlinear Diffusion, University of Houston , June 28 - July 2, 1976 .
National Science Foundation Regional Conference on Stability of Dynamical Systems, Mississippi State University , August 11-15, 1975 (invited speaker).
Sixth John H. Barrett Memorial Lecture Series, University of Tennessee , April 24-26, 1975 (invited speaker)
Science Research Council of the United Kingdom Conference on Functional Analysis and Differential Equations, University of London, Chelsea, April 1974.
Centro Internazionale Matematico Estivo Conference on Analysis, Bressanone , Italy , June 2-10, 1974 .
Symposium on General Analysis, Arkansas State University , April 28-29, 1972 .
Conference on Evolution Equations and Functional Analysis, University of Kansas , June 29- July 18, 1970 (invited speaker).
Conference on Equations of Evolution of Nonlinear Semigroups, University of Kentucky , May 29-31, 1969.
Partial Differential Equations and Applications, Laboratoire de Mathematiques et Applications, University of Poitiers, Poitiers, France, June 10, 2011.
Exploratory Workshop on Emerging Infectious Diseases and Mathematical Modelling, Centre de Recerca Matematica, Bellaterra, Barcelona, Spain, July 11-15, 2011 (invited speaker).
Mathematical Innovative Methods and Models of BIOsciences, University of Trent, Trento, Italy, December 19-21, 2011 (organizer and invited spearker).
Rocky Mountain Mathematics Consortium Summer School 2012, Mathematical Modeling in Ecology and Epidemiology, University of Wyoming, Laramie, Wyoming, June 11-22, 2012 (lecturer).
