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Updated: May 30, 2026

Immunostaining-Based Detection of Dynamic Alterations in Red Blood Cell Proteins
Published on: March 17, 2023
Effective temperature of red-blood-cell membrane fluctuations
Eyal Ben-Isaac1, Yongkeun Park, Gabriel Popescu
1Department of Chemical Physics, The Weizmann Institute of Science, Rehovot, Israel.
Abstract:
Biologically driven nonequilibrium fluctuations are often characterized by their non-Gaussianity or by an "effective temperature", which is frequency dependent and higher than the ambient temperature. We address these two measures theoretically by examining a randomly kicked particle, with a variable number of kicking motors, and show how these two indicators of nonequilibrium behavior can contradict. Our results are compared with new experiments on shape fluctuations of red-blood cell membranes, and demonstrate how the physical nature of the motors in this system can be revealed using these global measures of nonequilibrium.
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