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Updated: May 5, 2026

Creating Adhesive and Soluble Gradients for Imaging Cell Migration with Fluorescence Microscopy
Published on: April 4, 2013
Surface mobility gradient and emergent facilitation in glassy films
Qiang Zhai1, Xin-Yuan Gao2, Chun-Shing Lee3
1School of Physics, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an, Shaanxi, 710049, China. yangsen@mail.xjtu.edu.cn.
Abstract:
Confining glassy polymers into films can substantially modify their local and film-averaged properties. We present a lattice model of film geometry with void-mediated facilitation behaviors but free from any elasticity effect. We analyze the spatially varying viscosity to delineate the transport properties of glassy films. The film mobility measurements reported by Yang et al., Science, 2010, 328, 1676 are successfully reproduced. The flow exhibits a crossover from a simple viscous flow to a surface-dominated regime as the temperature decreases. The propagation of a highly mobile front induced by the free surface is visualized in real space. Our approach provides a microscopic treatment of the observed glassy phenomena.
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