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T Tlusty

Publications and source records attributed to T Tlusty.

5 recordsLinked to original sources
PubMed2000

Defect-induced phase separation in dipolar fluids.

A defect-induced, critical phase separation in dipolar fluids is predicted, which replaces the usual liquid-gas transition that is driven by the isotropic aggregation of particles and is absent in dipolar fluids due to strong chaining. The coexisting phases are a dilute gas of chain ends that coexists with a high-density liquid of chain branching points. Our model provides a unified explanation for the branched structures, the unusually low critical temperature and density, and the consequent two-phase coexistence "islands" that were recently observed in experiment and simulation.

Journal Article↗
PubMed2000

Topology, phase instabilities, and wetting of microemulsion networks

We predict theoretically the gradual formation of fluctuating, connected microemulsion networks from disconnected globules as the spontaneous curvature is varied, in agreement with recent direct measurements of these topological transitions. The connectivity induced instability together with emulsification failure of the network relate the ultralow tensions and wetting transition to the changing microstructure.

Journal Article↗
PubMed1999

Pearling in cells: a clue to understanding cell shape.

Gradual disruption of the actin cytoskeleton induces a series of structural shape changes in cells leading to a transformation of cylindrical cell extensions into a periodic chain of "pearls." Quantitative measurements of the pearling instability give a square-root behavior for the wavelength as a function of drug concentration. We present a theory that explains these observations in terms of the interplay between rigidity of the submembranous actin shell and tension that is induced by boundary conditions set by adhesion points. The theory allows estimation of the rigidity and thickness of this supporting shell. The same theoretical considerations explain the shape of nonadherent edges in the general case of untreated cells.

Actins↗
PubMed1998

Localized dynamic light scattering: a new approach to dynamic measurements in optical microscopy.

We present a new approach to probing single-particle dynamics that uses dynamic light scattering from a localized region. By scattering a focused laser beam from a micron-size particle, we measure its spatial fluctuations via the temporal autocorrelation of the scattered intensity. We demonstrate the applicability of this approach by measuring the three-dimensional force constants of a single bead and a pair of beads trapped by laser tweezers. The scattering equations that relate the scattered intensity autocorrelation to the particle position correlation function are derived. This technique has potential applications for measurement of biomolecular force constants and probing viscoelastic properties of complex media.

Biophysics↗