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Forming, Confining, and Observing Microtubule-Based Active Nematics
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Spiral and never-settling patterns in active systems.

X Yang1, D Marenduzzo2, M C Marchetti3

  • 1Physics Department, Syracuse University, Syracuse, New York 13244, USA.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|March 4, 2014
PubMed
Summary
This summary is machine-generated.

This study explores pattern formation in active systems, revealing how particle alignment, motility, and growth create stable or dynamic patterns like asters and spirals. These findings offer insights into bacterial suspensions and intracellular actin dynamics.

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Area of Science:

  • Active matter physics
  • Theoretical biology
  • Soft condensed matter

Background:

  • Active systems exhibit complex pattern formation.
  • Understanding these patterns is crucial for biological processes and synthetic materials.

Purpose of the Study:

  • To investigate pattern formation in a model active system with alignment, density-dependent motility, and logistic growth.
  • To explore the emergence of stable, blinking, aster, and spiral patterns.

Main Methods:

  • Combined numerical simulations and analytical techniques.
  • Modeling particle behavior with alignment, motility, and reaction terms.

Main Results:

  • In the disordered phase, motility suppression and growth compete, forming stable or blinking patterns.
  • Dense patterns develop orientational ordering, leading to asters or spirals.
  • In the ordered phase, a reaction term generates novel never-settling patterns.

Conclusions:

  • The model provides a framework for understanding pattern formation in bacterial suspensions and actomyosin systems.
  • Predicted patterns may be observable in chemotactic bacterial aggregates.
  • The study offers insights into intracellular actin dynamics and the formation of motile and spiral structures.