Roger Lentle is a professor at the Massey Institute of Food Science and Technology New Zealand. Here is an example publication from professor Lentle (along with co-author C. de Loubens) ‘A review of mixing and propulsion of chyme in the small intestine: fresh insights from new methods’ in: Journal of Comparative Physiology B, May 2015, Volume 185, Issue 4, pp 369-387.