Direction selection of metachronal waves in hydrodynamic coordination of cilia

Physical review. E, Journal Year: 2025, Volume and Issue: 111(3)

Published: March 4, 2025

Large arrays of active cilia coordinate their beat cycles into metachronal waves. These waves can travel in different directions with respect to the cilium's direction and resulting fluid propulsion. Hydrodynamic interactions provide a mechanism for individual cycles. Using an analytical framework that connects properties emergent wave behavior, I show how forcing pattern cycle breaks symmetry select direction. Previously, it was found second harmonic is dominant term coordination. Here, first enters coordination dynamics at higher order demonstrate important role terms play determining emerging

Language: Английский

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Cilia beating misalignment, immotility or death pathologically affect the efficiency of mucus-clearance

Communications Physics, Journal Year: 2025, Volume and Issue: 8(1)

Published: March 19, 2025

Language: Английский

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Collective Motion and Pattern Formation in Phase-Synchronizing Active Fluids

Physical Review Letters, Journal Year: 2023, Volume and Issue: 130(12)

Published: March 24, 2023

Many active particles, such as swimming micro-organisms or motor proteins, do work on their environment by going though a periodic sequence of shapes. Interactions between particles can lead to synchronization duty cycles. Here, we study the collective dynamics suspension coupled through hydrodynamics. We find that at high enough density system transitions state motion mechanism is distinct from other instabilities in matter systems. Second, demonstrate emergent nonequilibrium states feature stationary chimera patterns which synchronized and phase-isotropic regions coexist. Third, show confinement, oscillatory flows robust unidirectional pumping exist, be selected choice alignment boundary conditions. These results point toward new route pattern formation could guide design materials.

Language: Английский

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Role of cilia activity and surrounding viscous fluid in properties of metachronal waves

Physical review. E, Journal Year: 2024, Volume and Issue: 110(1)

Published: July 23, 2024

Large groups of active cilia collectively beat in a fluid medium as metachronal waves, essential for some microorganisms motility and flow generation mucociliary clearance. Several models can predict the emergence but what controls properties waves is still unclear. Here, we numerically investigate respective impacts beating viscous dissipation on collection oscillators, using simple model presence noise regular lattices one two dimensions. We characterize wave spatial correlation frequency collective beating. Our results clearly show that viscosity does not affect wavelength; activity does. These numerical are supported by dimensional analysis, which shows result wavelength invariance robust against taken sustained structure hydrodynamic coupling. Interestingly, enhancement increases decreases frequency, keeping velocity almost unchanged. might have significance understanding paramecium locomotion clearance diseases.

Language: Английский

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Near-field hydrodynamic interactions determine travelling wave directions of collectively beating cilia

Journal of The Royal Society Interface, Journal Year: 2024, Volume and Issue: 21(217)

Published: Aug. 1, 2024

Cilia can beat collectively in the form of a metachronal wave, and we investigate how near-field hydrodynamic interactions between cilia influence collective response beating cilia. Based on theoretical framework developed work Meng et al . (Meng 2021 Proc. Natl Acad. Sci. USA 118 , e2102828118), find that first harmonic mode driving force acting each individual cilium determine direction wave after considering finite size trajectories, which is confirmed by our agent-based numerical simulations. The stable patterns, e.g. travelling direction, be controlled forces cilia, based one change flow field generated This not only help to understand role behaviours but also guide future designs artificial desired dynamic mode.

Language: Английский

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An operative framework to model mucus clearance in silico by coupling cilia motion with the liquid environment

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 158(9)

Published: Feb. 9, 2023

Mucociliary clearance is the first defense mechanism of respiratory tract against inhaled particles. This based on collective beating motion cilia at surface epithelial cells. Impaired clearance, either caused by malfunctioning or absent cilia, mucus defects, a symptom many diseases. Here, exploiting lattice Boltzmann particle dynamics technique, we develop model to simulate multiciliated cells in two-layer fluid. First, tuned our reproduce characteristic length- and time-scales beating. We then check for emergence metachronal wave as consequence hydrodynamic mediated correlations between cilia. Finally, tune viscosity top fluid layer flow upon beating, evaluate pushing efficiency carpet With this work, build realistic framework that can be used explore several important physiological aspects mucociliary clearance.

Language: Английский

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Particle orbiting constrained by elastic filament as a model cilium for fluid pumping

Journal of Fluid Mechanics, Journal Year: 2023, Volume and Issue: 966

Published: June 29, 2023

Many microorganisms use cilia to propel themselves in low Reynolds number ( $Re$ ) environments. In this work, we study the dynamics of a composite cilium consisting an elastic filament and spherical particle attached at tip driven by external time-periodic force acting on particle. The is modelled numerically using slender body theory with hydrodynamic interactions. When tilted large angle from normal direction wall, buckles, induced velocity field shows net flux. By varying tilt or amplitude, trajectory flux display abrupt changes along reversal buckling direction. We further demonstrate through segmental model that arise deviation orientation start recovery stroke natural orientation. Our results suggest simple approach engineering motions designing artificial for fluid pumping

Language: Английский

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Structure-function relationships of mucociliary clearance in the human airways

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Dec. 24, 2023

Mucociliary clearance is a vital defense mechanism of the human airways, protecting against harmful particles and infections. When this process fails, it contributes to respiratory diseases like chronic obstructive pulmonary disease (COPD) asthma. While advances in single-cell transcriptomics have revealed complexity airway composition, much what we know about how structure impacts relies on animal studies. This limits our ability create accurate human-based models diseases. Here show that airways female rats humans exhibit species-specific differences distribution ciliated secretory cells as well ciliary beat, resulting significantly higher effectiveness humans. We further reveal standard lab-grown cultures lower compared identify underlying structural differences. By combining diverse experiments physics-based modeling, establish universal benchmarks assess function, interpret preclinical models, better understand disease-specific impairments mucociliary clearance.

Language: Английский

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Twist - torsion coupling in beating axonemes

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: March 18, 2024

Abstract Motile cilia and flagella are ubiquitous cell appendages whose regular bending waves pump fluids across tissue surfaces enable single-cell navigation. Key to these functions their non-planar waveforms with characteristic torsion. It is not known how torsion, a purely geometric property of the shape, related mechanical deformations axoneme, conserved cytoskeletal core flagella. Here, we assess torsion twist in reactivated axonemes isolated from green alga Chlamydomonas reinhardtii . Using defocused darkfield microscopy beat-cycle averaging, resolve 3D shapes axonemal waveform nanometer precision at millisecond timescales. Our measurements reveal hetero-chiral propagating base tip peak-to-peak amplitude 22 º/µm. To investigate if observed results twist, attach gold nanoparticles measure its cross-section rotation during beating. We find that locally, co-rotates plane. This co-rotation presents first experimental evidence for twist-torsion coupling indicates propagate along axoneme work thus links shape deformation beating axonemes, informing models motor regulation beat motile cilia.

Language: Английский

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Active fluctuations of axoneme oscillations scale with number of dynein motors

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: June 25, 2024

Fluxes of energy generate active forces in living matter, yet also fluctuations. As canonical example, collections molecular motors exhibit spontaneous oscillations with frequency jitter caused by non-equilibrium phase We investigate fluctuations reactivated Chlamydomonas axonemes, which are accessible to direct manipulation. quantify the precision axonemal after controlled chemical removal dynein motors, providing an experimental test for theory prediction that quality factor motor should increase number. Our quantification reveals specialized roles inner and outer arm motors. This supports a model dyneins serve as master pace-makers, become entrained, consistent recent insight provided structural biology.

Language: Английский

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