Thermo-statistics of irreversible processes: a Boltzmann-Gibbs-style ensemble formalism

The area of Physics indicated in the title is nowadays of quite relevant interest, not only from the purely scientific point of view, but specially for its applied aspects associated to the present-time point-first-technologies. A particular research trend in the theory of irreversible processes, which are evolving in time in systems arbitrarily departed from equilibrium, is here briefly described. It consists in the construction of a Gibbs-style nonequilibrium ensemble formalism. The derivation of a nonequilibrium statistical operator is described (the variational approach of Predictive Statistical Mechanics is used). The main questions involved are presented and applications are briefly mentioned.97106Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Considerations on undistorted-progressive X-waves and Davydov solitons, Fröhlich-Bose-Einstein condensation, and Cherenkov-like effect in biosystems

Research in ultrasonography has evidenced the propagation of a peculiar kind of excitation in fluids. Such excitation, dubbed a X-wave, has characteristics resembling that of a solitary-wave type. We reconsider the problem in a medium consisting of a biological material of the like of alpha-helix proteins. It can be shown that in this case is expected an excitation of the Davydov's solitary wave type, however strongly damped in normal conditions. The case of acetanilide, an organic polymer which resembles biopolymers, is considered, and the infrared spectrum analyzed. Davydov's soliton is evidenced as a coherent state of polar vibrations. The case of acoustic (sound) vibrations is also considered, where, also, a damped Davydov-like solitary wave may be excited. However, it is shown that when traveling in conditions sufficiently away from equilibrium, more precisely, when the soliton is embeded in the resulting Frohlich-Bose-Einstein condensate, the lifetime of the solitary wave is largely enhanced. Moreover, a soliton moving in bulk with a velocity larger than that of the group velocity of the normal vibrational waves would produce a Cherenkov-like emission of phonons giving rise to the observed X-wave-like pattern. This paper is a modified and extended version of an earlier publication on the subject.489503Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Electron mobility in nitride materials

We contribute here a theoretical study of the electron mobility in n-doped GaN, InN, and AlN at moderate to high electric fields. We solve the set of coupled nonlinear integro-differential equations of evolution to obtain the steady-state values of the basic intensive nonequilibrium thermodynamic variables for the three materials. The regions with ohmic and non-ohmic behavior in the electron drift velocity dependence on the electric field strength are characterized in the three nitrides. The electron mobility is calculated, and it is shown that the larger corresponds to InN, and the smaller to AlN.439441Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Impact of the repurposed drug thonzonium bromide on host oral-gut microbiomes

Drug repurposing is a feasible strategy for the development of novel therapeutic applications. However, its potential use for oral treatments and impact on host microbiota remain underexplored. Here, we assessed the influences of topical oral applications of a repurposed FDA-approved drug, thonzonium bromide, on gastrointestinal microbiomes and host tissues in a rat model of dental caries designed to reduce cross-contamination associated with coprophagy. Using this model, we recapitulated the body site microbiota that mirrored the human microbiome profile. Oral microbiota was perturbed by the treatments with specific disruption of Rothia and Veillonella without affecting the global composition of the fecal microbiome. However, disturbances in the oral-gut microbial interactions were identified using nestedness and machine learning, showing increased sharing of oral taxon Sutterella in the gut microbiota. Host-tissue analyses revealed caries reduction on teeth by thonzonium bromide without cytotoxic effects, indicating bioactivity and biocompatibility when used orally. Altogether, we demonstrate how an oral treatment using a repurposed drug causes localized microbial disturbances and therapeutic effects while promoting turnover of specific oral species in the lower gut in vivo

Ensemble formalism for nonequilibrium systems and an associated irreversible statical thermodynamics

It is reviewed what can be considered as the present research trends in what regards to the construction of an ensemble formalism - Gibbs' style - for the case of far-from-equilibrium systems. The main questions involved are presented accompanied with brief discussions. The construction of a nonequilibrium statistical operator is described and its applications commented, and, particularly, it is presented the derivation of an Irreversible Thermodynamics based on the statistical foundations that the nonequilibrium ensemble formalism provides.689717Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Participação e identidade profissional: A prática associativa de bibliotecários junto à associação de classe – ABMG / Participation and professional identity: The associative practice of libraries with the class association - ABMG

O presente artigo na perspectiva do desenvolvimento local, buscou compreender a partir dos processos políticos sociais e articulações interinstitucionais, a participação e a prática associativa de profissionais bibliotecários junto ao órgão de classe profissional. O problema investigado é verificar a partir do que descrevem alguns autores sobre a participação incipiente, tímida ou não participação dos bibliotecários em órgãos de classe, se esta situação atinge também os bibliotecários do sistema universitário. Como demonstrado por alguns autores, justifica-se o pouco interesse dessa classe trabalhadora em participar das associações de representação de classe profissional, com o desinteresse pelos espaços associativos. Muitos apontam a falta de formação política, questões culturais, rotinas de trabalho incompatíveis, também devido à prática participativa ser muito desgastante exigindo disponibilidade de tempo, empenho e estudo dentre tantos outros motivos. Aqui, o interesse específico é pela participação dos bibliotecários na Associação dos Bibliotecários de Minas Gerais (ABMG). Se há participação, é preciso pensar também sobre os critérios da qualidade política da associação: representatividade, legitimidade, participação de base e auto sustentação, analisados na perspectiva das relações estabelecidas entre o Sistema de Bibliotecas da UFMG e a associação de classe – ABMG, priorizando a perspectiva dos bibliotecários