Paper Number
BL31                         My Program 

Session
Biomaterials, Bio-fluid Dynamics and Biorheology

Title
Spatiotemporally-resolved differential dynamic microscopy reveals strain-induced deformation fields in cytoskeleton composites

Presentation Date and Time
October 21, 2025 (Tuesday) 2:50

Track / Room
Track 6 / Sweeney Ballroom C

Authors (Click on name to view author profile)

  1. Razzaghi, Aysan (University of San Diego, Physics and Biophysics)
  2. Valentine, Megan T. (university of California Santa Barbara, Mechanical Engineering)
  3. McGorty, Ryan J. (University of San Diego, Physics and Biophysics)
  4. Robertson-Anderson, Rae M. (University of San Diego, Physics and Biophysics)

Author and Affiliation Lines (in printed abstract book)
Aysan Razzaghi1, Megan T. Valentine2, Ryan J. McGorty3 and Rae M. Robertson-Anderson4
1Physics and Biophysics, University of San Diego, San Diego, CA 92108; 2Mechanical Engineering, university of California Santa Barbara, Santa Barbara, CA 93106; 3Physics and Biophysics, University of San Diego, San Diego, CA 92110; 4Physics and Biophysics, University of San Diego, San Diego, CA 92110

Speaker / Presenter 
Razzaghi, Aysan

Keywords
biomaterials; methods; microscopy

Text of Abstract
Active Cytoskeleton Composites (ACCs) are highly heterogeneous and noisy in structure, which leads to exhibition of complex responses to applied hydrodynamic forces. Characterizing such system requires highly resolved experimental and analysis method, both in space and time. We developed a unique method to unveil the highly complex dynamics of heterogeneous cytoskeleton composites undergoing shear stress, at scales comparable to that of composites mesh size. Using time-resolved differential dynamic microscopy (DDM) we achieve high resolution to study spatiotemporal shear propagation in kinesin-driven actin–microtubule composites. Alignment factor, degree of network alignment with the shear direction, exhibits a waveform pattern that varies with shear rate, motor protein concentration, and distance from the shear center. The amplitude of this waveform increases with motor protein concentration and spatially decays according to a power law.