My research primarily uses close analysis of the dynamics of a group or semigroup action on a space to discern properties of the group or semigroup. In particular, I am primarily interested in groups of automorphisms of a space and in semigroups of endomorphisms of a space. Supporting this, I have a secondary focus on topological and symbolic dynamics, which itself has lead me to an interest in...

The cellular and molecular effects of the proteasome inhibitor bortezomib on breast cancer cells are as yet poorly characterized. Here, in a panel of six breast cancer cell lines, bortezomib reduced viability in a concentration-dependent, time-dependent, and cell line-dependent manner. Proteasome activity was relatively high in two of the three more resistant cell lines. No relationship was obs...

Given a Sobolev homeomorphism f ? W 2,1 in the plane we find piecewise quadratic that approximates it up to set of ? measure. We show this map can be approximated by diffeomorphisms norm on set.

quantitative determination of br?nsted acid sites in acidic mordenite samples with varying proton concentrations has been studied using aqueous conductometric titration method. conductometric titration of the ammonium form of mordenite with sodium hydroxide is feasible and the results indicate potential number of br?nsted acid sites. however, br?nsted acid sites concentration in acidic mordenit...

introduction: radiography is one of the most important diagnostic methods for evaluation of dental caries. on the other hand, the least amount of radiation along with high quality is a main gold standard. the purpose of this study was to compare the diagnostic accuracy of primax, insight radiographic films, and direct digital images (schick cmos-aps), in detection of interproximal natural carie...

The dispersive lines observed in time-resolved femtosecond stimulated Raman spectroscopy (FSRS), using a pair of 809 nm, 3 ps Raman pump, and 840-960 nm ultrashort probe pulse, for the first 500 fs photoisomerization dynamics in the excited state of bacteriorhodopsin, BR* (S(1)), created by a prior 500 nm, 35 fs actinic pump pulse, have previously been attributed to Raman initiated by nonlinear...

Real-time nonlinear optical Fourier filtering for medical image processing is demonstrated, exploiting light modulating characteristics of thin films of the biophotonic material bacteriorhodopsin (bR). The nonlinear transmission of bR films for a 442 nm probe beam with a 568 nm control beam and vice versa is experimentally studied in detail. The spatial frequency information carried by the blue...

In this paper we prove results relating to two homotopy relations and four homology theories developed in the topology of digital images.<br /><br />We introduce a new type relation for digitally continuous functions which call ``strong homotopy.'' Both strong are natural digitizations classical topological homotopy: difference between them is analogous 4-adjacency 8-adjacency plane...