In order to achieve prescribed drug release kinetics over long therapeutic periods, bi-phasic and possibly multi-phasic releases from blends of biodegradable polymers are currently envisioned. The modelling of drug release in the presence of degradation of the polymer matrix and surface erosion is quite complex. Yet, simple reliable mathematical models validated against experimental data are no...

Recently Budkowski et al. used nuclear reaction analysis to study polymer brushes consisting of end-tethered deuterated polystyrene tails within a polystyrene homopolymer matrix. They measured the concentration-depth profile as a function of the surface

Shinpei Tanaka, Harold Fellermann, and Steen Rasmussen Graduate School of Integrated Arts and Sciences, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima 739-8521, Japan Center for Fundamental Living Technology (FLinT) Department of Physics, Chemistry and Pharmacy University of Southern Denmark, Campusvej 55 5230 Odense M, Denmark Santa Fe Institute, 1399 Hyde Park Rd, Santa Fe NM 87501...

A recently developed theory of atomic-scale local dielectric permittivity has been used to determine the position dependent permittivity profiles of a few nanoscale insulator surfaces and multilayers. Specifically, slabs containing single-component Si, polymer, and SiO2 and two-component Si-SiO2 and polymer-SiO2 systems of technological importance have been studied. The present approach indicat...

The issue of how best to cleave PMMAmicrostructured polymer optical fibres (mPOF) is addressed. The impact of the following parameters on the cleaving process is considered: (i) temperature of the cutting blade, (ii) temperature of the platen holding the fibre, (iii) time allowed for thermal equilibration between fibre and platen, (iv) blade speed, and (v) blade condition. The strong influence ...

The interpenetration function of some polymer mixture solutions in a good solvent is examined in the case of polymers of the same chemical species but with very different sizes. The results are compared to two theoretical models. In the first one, the polymers are considered as non-interpenetrating hard-spheres and, in the second one, a blob model of strongly interpenetrated chains is introduce...

For a long time one has associated to the Quantum Heisenberg Ferromagnet on a lattice, a random walk on the permutation group of the lattice vertices. We here present a polymer expansion for the solution of the heat equation coupled to the random walk. We work on a finite lattice, there is no question of convergence. We leave to future work bounding terms in the expansion necessary to extend th...