Sensitive particle shape dependence of growth-induced mesoscale nematic structure

Area of Science:

• * Computational modeling of biological systems.
• * Statistical physics of self-organizing matter.
• * Biophysics of microbial colony dynamics.

Background:

• * Multicellular systems exhibit self-organization driven by directed growth, cell shape, and confinement.
• * Understanding how microscopic properties influence macroscopic emergent behavior is crucial.
• * Rod-shaped bacteria colonies provide a model system for studying collective dynamics.

Purpose of the Study:

• * To investigate the impact of particle shape on microdomain formation and dynamics.
• * To explore how variations in rod-like particle shape affect self-organization in silico.
• * To link microscopic shape properties to macroscopic emergent patterns in growing aggregates.

Main Methods:

• * Developed a minimal in silico model of proliferating, sterically interacting particles.
• * Introduced tuneable tip variations to a rod shape with spherical caps.
• * Analyzed microdomain distribution, dynamics, and size distributions using an effective master equation model.

Main Results:

• * Subtle changes in particle shape significantly altered emergent dynamics and microdomain patterns.
• * Identified distinct effects of particle shape and aspect ratio on self-organization.
• * Observed a transition from exponential to scale-free microdomain size distributions.
• * Related size distribution differences to varying physical mechanisms of microdomain breakup.

Conclusions:

• * Particle shape is a critical determinant of self-organization in growing multicellular aggregates.
• * The study provides a framework for understanding how microscopic properties control macroscopic dynamics.
• * Findings are relevant for biological self-organization and the design of artificial systems.