Showing papers by "Udo Seifert published in 1998"
TL;DR: In this paper, the dynamics of a single fluid bilayer membrane in an external hydrodynamic flow field is considered and the deterministic equation of motion for the configuration is derived taking into account both viscous dissipation in the surrounding liquid and local incompressibility of the membrane.
Abstract: The dynamics of a single fluid bilayer membrane in an external hydrodynamic flow field is considered. The deterministic equation of motion for the configuration is derived taking into account both viscous dissipation in the surrounding liquid and local incompressibility of the membrane. For quasi-spherical vesicles in shear flow, thermal fluctuations can be incorporated in a Langevin-type equation of motion for the deformation amplitudes. The solution to this equation shows an overdamped oscillatory approach to a stationary tanktreading shape. Inclination angle and ellipiticity of the contour are determined as a function of excess area and shear rate. Comparisons to numerical results and experiments are discussed.
119 citations
TL;DR: Permeabilization of lipid bilayers by certain peptides involves perturbing lipid-lipid cohesive energies, and simulations show that at small line tensions the entropy of hole shape fluctuations destroys the model membrane's stability.
56 citations
TL;DR: In this article, the mean first passage time (MFPT) was proposed as the solution to a partial differential equation, which was solved numerically for a model case. But the MFPT was not applied to the case of a particle escape from a metastable well.
Abstract: Thermally activated escape of an over-damped particle from a metastable well under the action of a time-ramped force is studied. We express the mean first passage time (MFPT) as the solution to a partial differential equation, which we solve numerically for a model case. We discuss two approximations of the MFPT, one of which works remarkably well over a wide range of loading rates, while the second is easy to calculate and can provide a valuable first estimate.
36 citations
TL;DR: In this article, the critical behavior arising from thermally-excited shape fluctuations is determined both for global quantities such as the mean separation of these surfaces and for local quantities, such as probabilities for local contacts.
Abstract: Wetting phenomena, molecular protrusions of lipid bilayers and membrane stacks under lateral tension provide physical examples for interacting surfaces with tension. Such surfaces are studied theoretically using functional renormalization and Monte-Carlo simulations. The critical behavior arising from thermally-excited shape fluctuations is determined both for global quantities such as the mean separation of these surfaces and for local quantities such as the probabilities for local contacts.
13 citations
TL;DR: Investigators pursuing a reductionist approach have systematically studied the bare fluid membrane elasticity during the last ten years both theoretically and experimentally by using giant vesicles and have shown that a large variety of shapes and shape transformations can be explained simply on the basis of curvature elasticity and constraints on area and volume.
8 citations