On A Generalized Gibbs-boltzmann Ensemble Formalism For Dissipative Systems

The Nonequilibrium Statistical Operator Method, constructed on the basis of a generalized Gibbs-Boltzmann ensemble formalism, is gaining prominence as an approach to problems in statistical mechanics of nonequilibrium and nonlinear (dissipative) systems. In this paper, we consider the case of a generalized nonequilibrium grand-canonical ensemble. Besides the traditional densities of energy and particle number, this construction requires the introduction of the associated nonconserving dissipative fluxes of all orders. © 1998 Elsevier Science B.V. All rights reserved.2571-4424428Zubarev, D.N., Morosov, V.N., Röpke, G., (1996) Statistical Mechanics of Nonequilibrium Phenomena, Vol. 1: Basic Concepts, Kinetic Theory(1997) Relaxation and Hydrodynamic Processes, 2. , Akademie Verlag, Berlin, respectivelyLuzzi, R., Vasconcellos, A.R., (1990) Fortschr. Phys./Prog. Phys., 38, p. 887Madureira, J.R., Vasconcellos, A.R., Luzzi, R., A nonequilibrium statistical grand-canonical ensemble: Description in terms of flux operators, IFGW-unicamp internal report (1997) J. Chem. Phys., , in pressPeletminskii, S.V., Sokolovskii, A.I., (1974) Math. Theor. Phys. (USSR), 18, p. 121Luzzi, R., Vasconcellos, A.R., (1997) Physica A, 241, p. 667Ramos, J.G., Vasconcellos, A.R., Garcia-Colin, L.S., (1997) Braz. J. Phys., 27, p. 58

Film-nanoparticle composite for enhanced oral delivery of alpha-casozepine

Whey-derived alpha-casozepine bioactive peptide (YLGYLEQLLR) was associated with previously optimized guar-gum film-PLGA nanoparticles, aiming to increase both stability across gastrointestinal tract and permeability across absorptive epithelia. Oral films associated with nanoparticles (FNp) enhance buccal absorption along with protection of carried bioactive molecules that are swallowed, with inherent increase of bioavailability. None of developed formulations induced significant loss of cell viability. Permeability across both buccal and intestinal cell barriers was enhanced when alpha-casozepine was carried by FNp system, when compared with film and nanoparticles alone, in a simulated gastrointestinal tract environment. Moreover, differences in permeability profile across buccal and intestinal epithelia were in accordance with the slower erosion of PLGA nanoparticles in a media of neutral pH, resembling oral cavity conditions, and a faster erosion in acidic conditions, as occurs in stomach, as observed by a continuous analysis of nanoparticle morphology over 980 min by atomic force microscopy. Additionally, apparent permeability of alpha-casozepine across TR146 human buccal carcinoma cells and Caco-2/HT29-MTX co-culture, carried by FNp was indeed superior when compared with peptide loaded in PLGA nanoparticles and in films alone or with free peptide control solution. Both FNp and PLGA nanoparticles alone enhanced the permeability of relaxing peptide compared with guar-gum films alone. An increased tongue adhesion when PLGA nanoparticles were added to the guar-gum films was also observed. Developed formulations improved both buccal an intestinal absorption of carried bioactive molecules without compromising cell viability

Optical properties of III-nitrides in electric fields

78.30.Fs III-V and II-VI semiconductors, 78.20.Jq Electrooptical effects,