Front propagation in weakly subcritical pattern-forming systems.

The speed and stability of fronts near a weakly subcritical steady-state bifurcation are studied, focusing on the transition between pushed and pulled fronts in the bistable Ginzburg-Landau equation. Exact nonlinear front solutions are constructed and their stability properties investigated. In some cases, the exact solutions are stable but are not selected from arbitrary small amplitude initial conditions.

DNA models of trinucleotide frameshift deletions: the formation of loops and bulges at the primer-template junction.

Although mechanisms of single-nucleotide residue deletion have been investigated, processes involved in the loss of longer nucleotide sequences during DNA replication are poorly understood. Previous reports have shown that in vitro replication of a 3'-TGC TGC template sequence can result in the deletion of one 3'-TGC. We have used low-energy circular dichroism (CD) and fluorescence spectroscopy to investigate the conformations and stabilities of DNA models of the replication intermediates that may be implicated in this frameshift.