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arXiv · 0704.3846

Vesicle dynamics in elongation flow: Wrinkling instability and bud formation

Vasiliy Kantsler·Enrico Segre·Victor Steinberg
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Abstract

We present experimental results on the relaxation dynamics of vesicles subjected to a time-dependent elongation flow. We observed and characterized a new instability, which results in the formation of higher order modes of the vesicle shape (wrinkles), after a switch in the direction of the gradient of the velocity. This surprising generation of membrane wrinkles can be explained by the appearance of a negative surface tension during the vesicle deflation, due to compression in a sign-switching transient. Moreover, the formation of buds in the vesicle membrane has been observed in the vicinity of the dynamical transition point.

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Vasiliy Kantsler, Enrico Segre, Victor Steinberg. 2007-04-30. Vesicle dynamics in elongation flow: Wrinkling instability and bud formation. https://doi.org/10.1103/physrevlett.99.178102

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