Novel Supports Based on Polysaccharides for Sustained‐Release of Isosorbide Dinitrate

Novel supports based on carboxymethylcellulose (CMC), crosslinked with epichlorohydrin (EPC), and microparticles based on acetylphthalylcellulose (APC), for sustained‐release of isosorbide dinitrate (Isoket, Ik), were obtained. The drug has been included into CMC hydrogels through diffusion from ethanol‐water solution. Studies about the ethanol–water ratio influence on including the drug have shown an increased amount of included drug at higher content of water in the alcohol‐water mixture. Isoket–ACP microparticles have been obtained by drug and polymer co‐precipitation from emulsified aqueous solution.

The kinetics for “in vitro” release of Ik from polymeric materials, in simulated conditions for intestinal tract medium, where the drug is preferentially absorbed, has been analyzed. The experimental data have shown a “zero” order kinetic for drug release, which is characteristic for systems controlled by diffusion.     

A Multiplicity Result for an Elliptic Anisotropic Differential Inclusion Involving Variable Exponents

In this paper we are concerned with the study of a class of quasilinear elliptic differential inclusions involving the anisotropic $\overrightarrow {p}(\cdot)$ -Laplace operator, on a bounded open subset of ${\mathbb R}^n$ which has a smooth boundary. The abstract framework required to study this kind of differential inclusions lies at the interface of three important branches in analysis: nonsmooth analysis, the variable exponent Lebesgue–Sobolev spaces theory and the anisotropic Sobolev spaces theory. Using the concept of nonsmooth critical point we are able to prove that our problem admits at least two non-trivial weak solutions.     

On the Tightness of Capacities Associated with Sub-Markovian Resolvents

This paper investigates the tightness property of the capacityinduced by the reduction operator with respect to the resolventof a right Markov process. Tightness is verified in two particularsituations: under the ‘weak duality hypothesis’,and if a substitute for ‘the axiom of polarity for thedual theory’ holds. In the second context, the quasi-continuityproperty for the excessive functions is derived. These are extensionsand improvements of results of Lyons and Röckner, Ma andRöckner, Le Jan, and Fitzsimmons, mainly obtained in thecontext of Dirichlet forms. 2000 Mathematics Subject Classification31C25, 60J45 (primary), 31C15, 60J40 (secondary).     

Aspects of Number Theory in Terms of Potential Theory

We develop the Potential Theory on the set N^* of all natural numbers 2 associated with the kernel V (resp. V ^*) given by

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Fine Densities for Excessive Measures and the Revuz Correspondence

Suppose that U is the resolvent of a Borel right process on a Lusin space X. If is a U-excessive measure on X then we show by analytical methods that for every U-excessive measure with the Radon–Nikodym derivative d/d possesses a finely continuous version. (Fitzsimmons and Fitzsimmons and Getoor gave a probabilistic approach for this result.) We extend essentially a technique initiated by Mokobodzki and deepened by Feyel. The result allows us to establish a Revuz type formula involving the fine versions, and to study the Revuz correspondence between the -finite measures charging no set that is both -polar and -negligible (U being the potential component of ) and the strongly supermedian kernels on X. This is an analytic version of a result of Azéma, Fitzsimmons and Dellacherie, Maisonneuve and Meyer, in terms of additive functionals or homogeneous random measures. Finally we give an application to the context of the semi-Dirichlet forms, covering a recent result of Fitzsimmons.