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تسجيل مستخدم جديدQuantitative characterization of chemorepulsive alignment-induced interactions in active emulsions
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The constituent elements of active matter in nature often communicate with their counterparts or the environment by chemical signaling which is central to many biological processes. Examples range from bacteria or sperm that bias their motion in response to an external chemical gradient, to collective cell migration in response to a self-generated gradient. Here, in a purely physicochemical system based on self-propelling oil droplets, we report a novel mechanism of dynamical arrest in active emulsions: swimmers are caged between each others trails of secreted chemicals. We explore this mechanism quantitatively both on the scale of individual agent-trail collisions as well as on the collective scale where the transition to caging happens as a result of autochemotactic interactions.
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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 off-symmetric rati
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