On subshift presentations

Golden Mean Subshift Revised Introduction

We study subshifts of nite type on f0;1g Z 2 of the form where in a nite window there is always either one on no 1's present. The problem is converted to a tiling/covering problem on the (nZ) 2 lattice and its shifts. In this setup we consider the uniqueness of the equilibrium measure, density of 1's at equilibrium and the topological entropy. Further insight is achieved by realizing that the e...

On a substitution subshift related to the Grigorchuk group

The substitution acts on words (finite sequences) over this alphabet as well as on infinite sequences. It is easy to observe that τ has a unique invariant sequence ω that is the limit of words τ (a), k = 1, 2, . . . . Let Ω be the smallest closed set of one-sided infinite sequences over the alphabet {a, b, c, d} that contains ω and is invariant under the shift σ (σ acts on sequences by deleting...

Realizing Symmetries of a Subshift of Finite

Let A be a finite, irreducible, zero-one matrix and let CTA'XA —• XA be the corresponding subshift of finite type [F]. Recall from [F] that a Smale diffeomorphism is one with a hyperbolic zero-dimensional chain recurrent set. A well-known theorem of Williams-Smale [Wi] says that there is a Smale diffeomorphism FA'S —> S so that a A is topologically conjugate to the restriction of FA to the basi...

Oral Presentations Oral Presentations

ORAL PRESENTATIONS Discussion: Cross-resistance to different antibacterial agents including quinolones and nalidixic acid, chloramphenicol, trimethoprim and in some cases b-lactam antibiotics is a common phenomenon in Gram-negative bacteria (Gutmann et al., 1995). In this study adaptive resistance in Salmonella enterica and E. coli O157, O55 and K-12 was readily achieved by passage in sublethal...

Oral Presentations Oral Presentations