Thin-filament theory

The significance of fhe second assumption is that the deformation field in the film is essentially elongational. Shear stresses are not present, if the film thickness is very small. The first assumption makes the final equations simpler without losing any significant information. Finally, overall these assumptions resemble those used in Section 9.1.2 in the thin-filament theory for the fiber-spinning process. 

Apart from the phosphorylation theory, other regulatory mechanisms have also been suggested for smooth muscle contraction. A thin-filament protein that has been proposed as a regulatory component is caldesmon [102], Purified caldesmon is a potent inhibitor of actin-tropomyosin interaction with myosin. The mechanisms by which calcium removes this inhibition are controversial. Furthermore, phosphorylation of caldesmon by a caldesmon kinase in vitro has also been implicated in this... 

Draw resonance is a particularly good example of a processing instability because it has a clear signature and a sharp onset. Furthermore, the onset is amenable to rigorous analysis because of the simplicity of the thin filament spinning equations developed in Chapter 7. The approach we use here is linear stability theory, which asks a very specific question ... 

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