English
Related papers

Related papers: Activity gradients in two- and three-dimensional a…

200 papers

Dense, active systems show active turbulence, a state characterised by flow fields that are chaotic, with continually changing velocity jets and swirls. Here we review our current understanding of active turbulence. The development is…

Soft Condensed Matter · Physics 2016-08-03 Sumesh P. Thampi , Julia M. Yeomans

We investigate numerically, by a hybrid lattice Boltzmann method, the morphology and the dynamics of an emulsion made of a polar active gel, contractile or extensile, and an isotropic passive fluid. We focus on the case of a highly…

Soft Condensed Matter · Physics 2019-02-28 Giuseppe Negro , Livio Nicola Carenza , Pasquale Digregorio , Giuseppe Gonnella , Antonio Lamura

We use analytic arguments and numerical solutions of the continuum, active nematohydrodynamic equations to study how friction alters the behaviour of active nematics. Concentrating on the case where there is nematic ordering in the passive…

Soft Condensed Matter · Physics 2024-04-23 Mehrana Raeisian Nejad , Amin Doostmohammadi , Julia Mary Yeomans

We adapt the Halperin-Mazenko formalism to analyze two-dimensional active nematics coupled to a generic fluid flow. The governing hydrodynamic equations lead to evolution laws for nematic topological defects and their corresponding density…

Soft Condensed Matter · Physics 2021-05-11 Luiza Angheluta , Zhitao Chen , M. Cristina Marchetti , Mark J. Bowick

Active nematic fluids exhibit complex dynamics in both bulk and in simple confining geometries. However, complex confining geometries could have substantial impact on active spontaneous flows. Using multiparticle collision dynamics…

Soft Condensed Matter · Physics 2025-01-16 Jaideep P. Vaidya , Tyler N. Shendruk , Sumesh P. Thampi

We numerically solve the active nematohydrodynamic equations of motion, coupled to a Turing reaction-diffusion model, to study the effect of active nematic flow on the stripe patterns resulting from a Turing instability. If the activity is…

Soft Condensed Matter · Physics 2021-11-04 Saraswat Bhattacharyya , Julia M. Yeomans

Active nematics are microscopically driven liquid crystals that exhibit dynamical steady states characterized by the creation and annihilation of topological defects. Motivated by experimental realizations of such systems made of biopolymer…

Soft Condensed Matter · Physics 2018-09-05 Abhijeet Joshi , Elias Putzig , Aparna Baskaran , Michael Hagan

In nature interactions between biopolymers and motor proteins give rise to biologically essential emergent behaviours. Besides cytoskeleton mechanics, active nematics arise from such interactions. Here we present a study on 3D active…

We study the structure and dynamics of the interface separating a passive fluid from a microtubule-based active fluid. Turbulent-like active flows power giant interfacial fluctuations, which exhibit pronounced asymmetry between regions of…

Active fluids exhibit spontaneous flows with complex spatiotemporal structure, which have been observed in bacterial suspensions, sperm cells, cytoskeletal suspensions, self-propelled colloids, and cell tissues. Despite occurring in the…

Soft Condensed Matter · Physics 2022-10-05 Ricard Alert , Jaume Casademunt , Jean-François Joanny

We introduce a two-dimensional active nematic with quenched disorder. We write the coarse-grained hydrodynamic equations of motion for slow variables, viz. density, and orientation. Disorder strength is tuned from zero to large values.…

Soft Condensed Matter · Physics 2021-07-15 Sameer Kumar , Shradha Mishra

With quenched disorder, we introduce two-dimensional active nematics suspended in an incompressible fluid. We write the coarse-grained hydrodynamic equations of motion for slow variables, viz. density, orientation and flow fields. The…

Soft Condensed Matter · Physics 2022-10-14 Sameer Kumar , Shradha Mishra

We develop a formal analogy between configurational stresses in two distinct physical systems, and study the flows that they induce when the configurations of interest include topological de- fects. The two systems in question are…

Soft Condensed Matter · Physics 2018-03-23 Christopher Conklin , Jorge Vinals , Oriol T. Valls

In microtubule-based active nematics, motor-driven extensile motion of microtubule bundles powers chaotic large-scale dynamics. We quantify the interfilament sliding motion both in isolated bundles and in a dense active nematic. The…

The growing interest in active nematics and the emerging evidence of the relevance of topological defects in biology asks for reliable data analysis tools to identify, classify and track such defects in simulation and microscopy data. We…

Soft Condensed Matter · Physics 2020-02-10 Dennis Wenzel , Michael Nestler , Sebastian Reuther , Maximilian Simon , Axel Voigt

Active emulsions and liquid crystalline shells are intriguing and experimentally realisable types of topological matter. Here we numerically study the morphology and spatiotemporal dynamics of a double emulsion, where one or two passive…

We develop a continuum theory to describe the collective dynamics of deformable epithelial cells, using two tensor order parameters to distinguish the force-generating active filaments in the cells from their shape. The theory demonstrates…

Soft Condensed Matter · Physics 2025-01-13 Mehrana R. Nejad , Julia M. Yeomans , Sumesh P Thampi

The surface tension of living cells and tissues originates from the generation of nonequilibrium active stresses within the cell cytoskeleton. Here, using laser ablation, we generate gradients in the surface tension of cellular aggregates…

Cell crawling crucially depends on the collective dynamics of the acto-myosin cytoskeleton. However, it remains an open question to what extent cell polarization and persistent motion depend on continuous regulatory mechanisms and…

Biological Physics · Physics 2023-08-11 Fenna Stegemerten , Karin John , Uwe Thiele

The structure and dynamics of important biological quasi-two-dimensional systems, ranging from cytoskeletal gels to tissues, are controlled by nematic order, flow, defects and activity. Continuum hydrodynamic descriptions combined with…

Biological Physics · Physics 2024-12-03 Waleed Mirza , Alejandro Torres-Sánchez , Guillermo Vilanova , Marino Arroyo