日時：	2026年11月27日（金）13：30～15：00
場所：	医生物学研究所　医生研３号館５階501室 Room 501, 5th floor, Bldg. #3 Institute for Life and Medical Sciences, Kyoto University
演者：	Dapeng "Max" Bi Department of Physics and the Center for Theoretical Biological Physics Northeastern University, USA
演題：	Order, Flow, and Rigidity in Biological Tissues

講演要旨

今回は、Northeastern UniversityのDapeng Bi博士に、
ソフトマターや統計物理学に基づく組織形態形成機構の解明について、お話しいただきます。
関心のある方の積極的な参加を歓迎いたします。

Biological tissues are dense, active materials that must be solid
enough to hold their shape yet fluid enough to remodel during
development, wound healing, and disease. In this talk, I will show how
ideas from soft matter and statistical physics reveal the structural
and mechanical states of confluent tissues. First, I will discuss how
tissues respond to deformation. A floppy, fluid-like tissue can
rigidify under shear through a geometry-controlled stiffening
transition. When external shear competes with internal active
stresses, tissues near the jamming transition display rich nonlinear
rheology, from yielding and shear thinning to discontinuous shear
thickening. Like yield stress materials, tissues flow through
avalanches of collective cell rearrangements, and their statistics
allow mechanical stress to be inferred from static images alone.
Second, I will show how geometry shapes tissue fluidity: on curved
epithelia, surface curvature lowers the energy barriers to
rearrangement and drives unjamming. Third, I will turn to structural
order. Cell division and motility together give rise to a reentrant
hexatic phase, while on growing lung spheroids, packing order is
controlled by topology and nuclear size. Beyond local order, cellular
packings can display hidden long-range order through hyperuniformity.
Together, these results show that living tissues access states of
matter and mechanical responses with no direct analog in passive
materials.(Language: English)

20261127_Theoretical Biology Seminar（Dapeng Max Bi氏_Northeastern University）

Host:
contact: Atsushi Mochizuki
Laboratory of Mathematical Biology,
Institute for Life and Medical Sciences,
Kyoto University
Email: mochi[@]infront.kyoto-u.ac.jp
Tel: 075-751-4612