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Updated: Jan 2, 2026
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
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Chiral stresses in nematic cell monolayers.
Ludwig A Hoffmann1, Koen Schakenraad, Roeland M H Merks
1Instituut-Lorentz, Leiden University, P.O. Box 9506, 2300 RA Leiden, The Netherlands. giomi@lorentz.leidenuniv.nl.
Soft Matter
|December 13, 2019
Summary
Chirality in cell monolayers introduces asymmetry in collective flow, allowing measurement of chiral stress. This finding impacts understanding of active nematic hydrodynamics and cellular collective motion.
Area of Science:
- Physics of living systems
- Cellular biophysics
- Soft matter physics
Background:
- Active nematic hydrodynamics successfully models epithelial cell collective behavior.
- Experiments reveal unexpected features, suggesting chirality's role beyond cellular scales.
Purpose of the Study:
- Elucidate the microscopic origin of chiral stresses in nematic cell monolayers.
- Investigate chirality's impact on topological defect motion and collective cell flow.
- Analyze how chirality influences spontaneous flow transitions under confinement.
Main Methods:
- Theoretical modeling of chiral stresses in nematic cell monolayers.
- Analysis of collective cellular flow patterns on stripe-shaped domains.
- Particle-image-velocimetry (PIV) measurements to quantify flow asymmetry.
Main Results:
- Chirality induces a measurable asymmetry in collective cellular flow.
- The ratio of chiral to non-chiral active stresses can be inferred from flow measurements.
- Chirality alters spontaneous flow transitions, exhibiting an imperfect pitchfork bifurcation under confinement.
Conclusions:
- Chirality is a significant factor in active nematic cell monolayers, influencing collective behavior.
- Quantifying chiral stresses provides deeper insights into cellular dynamics and tissue morphogenesis.
- The observed bifurcation structure offers a new perspective on pattern formation in confined cellular systems.
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