Biolocomotion and premelting in ice

Abstract

Biota are found in glaciers, ice sheets and permafrost. Ice bound micro-organisms evolve in a complex mobile environment facilitated or hindered by a range of bulk and surface interactions. When a particle is embedded in a host solid near its bulk melting temperature, a melted film forms at the surface of the particle in a process known as interfacial premelting. Under a temperature gradient, the particle is driven by a thermomolecular pressure gradient toward regions of higher temperatures in a process called thermal regelation. When the host solid is ice and the particles are biota, thriving in their environment requires the development of strategies, such as producing exopolymeric substances (EPS) and antifreeze glycoproteins (AFP) that enhance the interfacial water. Therefore, thermal regelation is enhanced and modified by a process we term {\em bio-enhanced premelting}. Additionally, the motion of bioparticles is influenced by chemical gradients influenced by nutrients within the icy host body. We show how the overall trajectory of bioparticles is controlled by a competition between thermal regelation and directed biolocomotion. By re-casting this class of regelation phenomena in the stochastic framework of active Ornstein-Uhlenbeck dynamics, and using multiple scales analysis, we find that for an attractive (repulsive) nutrient source, that thermal regelation is enhanced (suppressed) by biolocomotion. This phenomena is important in astrobiology, the biosignatures of extremophiles and in terrestrial paleoclimatology.

References in corpus (25)

• Active Particles in Complex and Crowded Environments
• Physics of Microswimmers - Single Particle Motion and Collective Behavior
• Active Brownian Particles. From Individual to Collective Stochastic Dynamics
• Dynamic clustering in active colloidal suspensions with chemical signaling
• How far from equilibrium is active matter?
• Diffusive transport without detailed balance in motile bacteria: Does microbiology need statistical physics?
• Clusters, asters and collective oscillations in chemotactic colloids
• Chemotaxis and auto-chemotaxis of self-propelling artificial droplet swimmers
• Statistical Mechanics of Active Ornstein Uhlenbeck Particles
• Irreversibility in active matter systems: Fluctuation theorem and mutual information
• Dynamic clustering and chemotactic collapse of self-phoretic active particles
• Generalized energy equipartition in harmonic oscillators driven by active baths
• Self-propelled particles with fluctuating speed and direction of motion
• E. coli chemotaxis is information-limited
• Chemotactic self-caging in active emulsions
• Motion of an Adhesive Gel in a Swelling Gradient: a Mechanism for Cell Locomotion
• Generalized Ornstein-Uhlenbeck Model for Active Motion
• Dynamics of active particles with space-dependent swim velocity
• How irreversible are steady-state trajectories of a trapped active particle?
• Irreversibility in active matter: General framework for active Ornstein-Uhlenbeck particles
• A fine balance of chemotactic and hydrodynamic torques: when microswimmers orbit a pillar just once
• Impurity effects in thermal regelation
• Onsager reciprocity in premelting solids
• Diffusion of a Brownian ellipsoid in a force field
• Premelting controlled active matter in ice