Speaker: Dr. Pradip K. Bera, Postdoctoral Research Associate, Department of Mechanical Engineering, 
         University of Wisconsin-Madison, USA.

Title: "From Cell Shape to Dissipation: The Physics of Epithelial Tissue Fluidity".

Date: Friday, 9th October 2026 - Time: 4 PM

Venue: CeNSE Seminar Hall

Abstract:

What controls whether an epithelial tissue behaves more like a solid or a fluid? Using epithelial 
cell monolayers in vitro as model living materials, we investigate this question by perturbing 
cell-cell adhesion. We find substantial fluidization without appreciable changes in cell shape, 
density, cell-substrate traction, or junctional tension, challenging the prevailing geometry-based 
picture of tissue fluidity. An extended vertex model incorporating dissipative resistance to cell-edge 
remodeling quantitatively reproduces this shape-independent fluidization. These results reveal a dual 
energetic and dissipative role of cell-cell adhesion and suggest that tissue fluidity emerges from the 
interplay between geometry and dissipation in living active materials.

Biography:

Dr. Pradip K. Bera is a Postdoctoral Research Associate in mechanical engineering at the University 
of Wisconsin-Madison. He received his B.Sc. (Honours) in Physics from Vidyasagar University, M.Sc. in 
Physics from IIT Delhi, and Ph.D. in Physics from IISc Bangalore, where he studied driven soft matterials 
and active granular systems. His research interests include soft matter, rheology, active matter, and cell 
biophysics. He develops approaches integrating microscopy, traction force microscopy, rheology, in-situ 
X-ray scattering, fluorescence correlation methods, and computational image analysis to study living and 
synthetic nonequilibrium systems.

Host Faculty:  Prof. Ambarish Ghosh