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Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
Dynamics of a compound vesicle in shear flow
Shravan K Veerapaneni1, Y-N Young, Petia M Vlahovska
1Courant Institute of Mathematical Sciences, NYU, New York, New York 10012, USA.
Physical Review Letters
|May 17, 2011
Summary
This study reveals how internal particles affect vesicle movement in fluid flow. Non-spherical particles cause vesicles to swing, and viscosity differences aren't always needed for tumbling transitions.
Area of Science:
- Biophysics
- Fluid Dynamics
- Cellular Mechanics
Background:
- Vesicles are fundamental cellular structures with lipid bilayer membranes enclosing fluids and particles.
- Understanding vesicle dynamics in shear flow is crucial for comprehending cellular behavior in biological systems, particularly in microcirculation.
Purpose of the Study:
- To investigate the dynamics of compound vesicles in shear flow using numerical simulations and theoretical analysis.
- To identify novel features of vesicle behavior arising from hydrodynamic interactions between internal particles and the vesicle membrane.
Main Methods:
- Employed numerical simulations to model vesicle behavior.
- Utilized theoretical analysis to complement simulation findings.
Main Results:
- Discovered that nonlinear hydrodynamic interactions can induce transitions from tank treading to tumbling, independent of viscosity mismatches.
- Observed that nonspherical internal particles can cause vesicles to exhibit swinging motion.
- Demonstrated complex effects of internal structures on cell dynamics in microcirculatory flows, using malaria-infected erythrocytes as an example.
Conclusions:
- Internal cellular structures significantly influence cell dynamics in microcirculatory flows.
- The presence and shape of internal particles introduce unique dynamic behaviors in vesicles.
- Findings have implications for understanding blood viscosity changes due to internal cellular alterations, such as in malaria.
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