Applied Math Seminar

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Instabilities, Flow Control and Patterning in Living Tissues

Speaker: Mattia Serra, UC San Diego

Location: Warren Weaver Hall 1302

Date: Friday, February 6, 2026, 2:30 p.m.

Synopsis:

Embryogenesis couples complex tissue flows with precise spatial patterning, yet how cell motion mediates morphogen organization remains unclear. I will first present a nonlinear continuum model—a system of coupled PDEs for tissue velocity and mechanosensitive myosin—that explains the motion of thousands of cells during early chick embryo development. Linear stability analysis reveals an active-stress instability as the primary driver of tissue flows, confirmed experimentally. Guided by the model, we demonstrate experimental control of tissue flows in vivo, generating drastically distinct flow topologies and their associated Lagrangian attractors and repellers. If time permits, I will introduce a mathematical framework for morphogen patterning in dynamic tissues. The framework identifies new dimensionless numbers—distinct from Péclet—based on Lyapunov times and tissue deformation that reveal when/where morphogenesis fundamentally alters patterning; and introduces the notion of embryological light cones to quantify effective cell–cell interaction ranges in dynamic tissues from data.

https://www.nature.com/articles/s41467-025-60249-8
https://journals.aps.org/prxlife/abstract/10.1103/h74q-3dgj