Modeling polymorphic transformation of rotating bacterial flagella in a viscous fluid

Model for polymorphic transitions in bacterial flagella.

Many bacteria use rotating helical flagellar filaments to swim. The filaments undergo polymorphic transformations in which the helical pitch and radius change abruptly. These transformations arise in response to mechanical loading, changes in solution temperature and ionic strength, and point substitutions in the amino acid sequence of the protein subunits that make up the filament. To explain ...

Force-extension measurements on bacterial flagella: triggering polymorphic transformations.

Bacterial flagella can adopt several different helical shapes in response to varying environmental conditions. A geometric model by Calladine ascribes these discrete shape changes to cooperative transitions between two stable tertiary structures of the constituent protein, flagellin, and predicts an ordered set of 12 helical states called polymorphic forms. Using long polymers of purified flage...

Thermodynamic Parameters Modeling of Viscous Flow Activation in Ethylene Glycol-Water Fluid Systems

Calculation of excess quantities of ethylene glycol + water binary fluid systems at seven absolute temperatures (293.15 to 353.15) K from experimentally determined values of density and shear viscosity were presented in previous work. The examination of related functions beside the quality of correlation from several equations on these experimental values has also been reported. Considering...

Self-propulsion of a counter-rotating cylinder pair in a viscous fluid

Numerical Solution For The Deceleration of A Rotating Disk in A Viscous Fluid

-The unsteady similarity equations have been obtained for a disk rotating in a viscous fluid that decelerates with angular velocity proportional to time. The resulting ordinary differential equations have been solved numerically using an easy numerical technique for range 0 100    s of the non-dimensional parameter s which measures unsteadiness. The calculations have been carried out using t...