Time lapse confocal microscopy studies of bacterial adhesion to self-assembled monolayers and confirmation of a novel approach to the thermodynamic model.

In this study, we use thermodynamic theory to develop a novel model that allows for the quantitative determination of the Gibbs free energy of adhesion for the initial bacterial attachment process. This model eliminates the need to calculate interfacial free energies and instead relies on easily measurable contact angles to determine DeltaG(adh). We experimentally verify our model using real-time observation of the initial attachment of Pseudomonas putida to methyl- and hydroxyl-terminated self-assembled monolayers.

Hydration study of homopolypeptides by (2)H NMR.

Deuteron T(1) and T(2) was studied as a function of hydration in homopolyglycine (PG) and homopolyproline (PP). Water deuteron relaxation rates in PG conform to a hydration model involving two types of primary hydration sites where water is directly bonded to the polymer. Once these sites are filled, additional water only bonds to water molecules at the primary sites and in so doing affect their dynamics.

Infinite-order excitonic BLOCH equations for asymmetric nanostructures.

We present a new exciton-based formalism for calculating the coherent response of asymmetric semiconductor multiple quantum well structures to ultrashort optical pulses valid to infinite order in the optical field and including the self-generated intraband fields. We use these equations to calculate and explain the oscillations with time delay of peaks in the spectrally resolved degenerate four-wave mixing signals from biased semiconductor superlattices, obtaining good agreement with experiment.