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Updated: Jan 11, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Segregation, finite-time elastic singularities, and coarsening in renewable active matter.
Ayan Roychowdhury1, Saptarshi Dasgupta1, Madan Rao1
1National Centre for Biological Sciences-TIFR, Simons Centre for the Study of Living Machines, Bengaluru 560065, India.
Physical Review. E
|November 18, 2025
Summary
Active living systems, like the cytoskeleton, use material renewability to generate patterned forces. This study models actomyosin elastomers, revealing spontaneous stress patterns that evolve into self-similar structures, impacting cell mechanics.
Area of Science:
- Biophysics
- Cell Biology
- Materials Science
Background:
- Material renewability is crucial for force generation and patterning in active living systems, particularly the cell cytoskeleton.
- Actomyosin networks, composed of actin and myosin, generate contractile stresses and exhibit differential turnover, leading to patterned force channeling.
- Understanding these dynamics is key to comprehending cellular structure and function.
Purpose of the Study:
- To investigate the dynamical patterning of stresses in a renewable active actomyosin elastomer.
- To analyze the behavior of elastomers with one or two myosin species using a hydrodynamic description.
- To explore the implications for cytoskeletal organization and cellular phenotypes.
Main Methods:
- Developed a hydrodynamic framework to describe a renewable active actomyosin elastomer.
- Employed analytical methods to study stress patterning.
- Utilized one-dimensional numerical analysis to observe the evolution and merging of stress structures.
Main Results:
- A uniform active contractile elastomer spontaneously segregates into spinodal stress patterns.
- These patterns collapse into tension-carrying singular structures exhibiting self-similar scaling and caustics.
- Numerical simulations show these structures move, merge, and lead to slow coarsening dynamics.
Conclusions:
- The study provides insights into the emergence of stress fibers and spatial patterning of actomyosin.
- Actomyosin elastomers can spontaneously generate complex stress patterns.
- State-dependent turnover mechanisms allow the cytoskeleton to achieve diverse functional phenotypes.
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