Thermodynamic models for water sorption by grape skin and pulp

The enthalpy-entropy compensation theory was applied to water sorption for grapes of Italy variety. The moisture sorption isotherms were analyzed using the static gravimetric method at 35, 40, 50, 60, 70 and 75 degrees C. For isotherms construction, the skin and pulp of the grape were used separately and it was possible to observe significant differences. The GAB equation was fitted to the experimental data, using direct nonlinear regression analysis; the agreement between experimental and calculated values was satisfactory. The net isosteric heat or enthalpy of water sorption, determined from the equilibrium sorption data, showed a different behavior when compared with other works, as it was obtained for skin and pulp separately. Plots of Delta h vs Delta S for skin and pulp provided the isokinetic temperatures T-Bs = 423.2 +/- 27.6 K and T-Bp = 424.5 +/- 25.3 K, respectively, indicating an enthalpy-controlled desorption process over the whole range of moisture content considered.

Temperature effect on seed germination in Canna indica L. (Cannaceae)

Comm indica L. is an herbaceous species with ornamental and medicinal value, having seeds with a hard seed coat. This study aimed to test the influence of constant temperatures ranging from 5 to 45 C, at 5 C intervals, on the germination of scarified seeds. Data obtained were analyzed through the model of enthalpy of activation in order to obtain the optimum temperature range for germination. The species showed seed germinability in a wide temperature range (10-40 degrees C) being the optimal temperature range between 13.84 and 34.41 degrees C, determined by the enthalpy of activation.

Efeito dose-resposta de uma formulação de dentifrício com concentração reduzida de fluoreto - estudo in vitro.

The utilization of dentifrices with low fluorine concentration, for children under 6 years of age, has been suggested to reduce the risks of dental fluorosis. However, in order to have anticariogenic potential, the dentifrice should form loosely-bound fluorine (CaF2) on dental enamel. Considering that the formation of CaF2 is a function inversely related to pH, dentifrices with pH 5.5, with 275, 550 and 1,100 ppm F (NaF/silica) were developed in order to assess dose-response effects. A comparison between those dentifrices, a placebo product and the Crest toothpaste (positive control - standard) was carried out. Furthermore, the bioavailability of dentifrices, in terms of formation of total fluorine (TF), CaF2, and fluorapatite (FA) on human dental enamel, was evaluated. An ion-specific electrode was utilized for the determination of the dosage of fluorine. The results revealed that the dentifrice with 550 ppm F was more effective than both the placebo and the dentifrice with 275 ppm, presenting no difference in relation to the positive control (p > 0.05). A dose-effect correlation was observed as to the CaF2 formed. In conclusion, the modified formulation with 550 ppm F can be considered as effective as the standard dentifrice with 1,100 ppm, and its utilization would be safer with regard to dental fluorosis.

Multipartite quantum correlations in open quantum systems

In this paper, we present a measure of quantum correlation for a multipartite system, defined as the sum of the correlations for all possible partitions. Our measure can be defined for quantum discord (QD), geometric quantum discord or even for entanglement of formation (EOF). For tripartite pure states, we show that the multipartite measures for the QD and the EOF are equivalent, which allows direct comparison of the distribution and the robustness of these correlations in open quantum systems. We study dissipative dynamics for two distinct families of entanglement: a W state and a GHZ state. We show that, for the W state, the QD is more robust than the entanglement, while for the GHZ state, this is not true. It turns out that the initial genuine multipartite entanglement present in the GHZ state makes the EOF more robust than the QD. © IOP Publishing and Deutsche Physikalische Gesellschaft.

Aspectos fundamentais no desenvolvimento de sistemas microemulsionados contendo anfotericina B para uso oftálmico

As occurs with a number of drugs, the bioavailability of amphotericin B (AmB) used to treat fungal infections by the ocular route remains a great challenge to research scientists. In fact, the poor bioavailability of AmB is due mainly to the corneal barrier, which leads to a precorneal loss and consequent decrease in the absorption of this drug into the intraocular tissues. The toxicity associated with this molecule, together with its poor ability to penetrate the intact corneal epithelium, also represents a major drawback to its clinical use. New effective and safe drug vehicles for ocular delivery of AmB are therefore urgently needed. Microemulsions (MEs) seem to be an interesting system, owing to their transparent appearance, thermodynamic stability and favorable viscosity. Knowledge of the process of formation of AmB-containing MEs, as well as a good understanding of the physical chemistry of such systems, would provide reliable information on the best conditions for the use of these systems as eye drops. The goal of this research was thus to make an approach to this subject by reviewing the main studies on the use of MEs as delivery systems for AmB in topical eye treatment.

Caracterização de terras pretas arqueológicas no sul do Estado do Amazonas

The Archaeological Dark Earth (ADE) soils are characterized by its high fertility, dark color, and presence of pottery fragments. Regarding the formation of ADE, the most widely accepted hypothesis is that anthropogenic processes involving pre-Columbian populations made them. The purpose of this study is to characterize ADE units located in the Southern Amazon Region, in the cities of Apuí and Manicoré. Seven ADE sites were selected, trenches opened and the soil profiles characterized morphologically. Then, samples of each horizon were collected for analyses of the following physical and chemical properties: particle size, water-dispersible clay, flocculation, soil bulk density, particle density, total porosity, pH in water and KCl solutions, Ca2+, Mg2+, K+, Al3+, available P, H+Al, and organic C. Also, total oxides, free oxides and amorphous forms were analyzed. The texture of the anthropic A horizon ranged from sandy loam to clay loam. The pottery fragments and lithic material were found in similar quantities and at similar depths in the A horizons of the studied soil profiles, suggesting some similarity between the anthropogenic factors of formation. The anthropic horizons of profiles P3, P4, and P7 had a eutrophic character and high to very high levels of available phosphorus, compared to P1, P2, P5, and P6, indicating the heterogeneity of the ADEs.

Caracterização dos agregados em solos sob cultivo no Cerrado, MS

Impacts on the environment and soil biological activity result in changes in the processes of formation of biogenic and fisiogenic aggregates. Aiming to evaluate the influence on physical and biological genesis of aggregates of Cerrado soils and determine the main environmental factors that determine the characteristics of households in the area of production under integrated crop-livestock (ICL), was developed this study in Farm Cabeceira, Maracaju-MS, in areas of ICL. The areas evaluated were: Savana, pasture/maize, corn/cotton and cotton/soybeans being evaluated during the dry (May/2009) and rainy (March 2010) season. To identify the pathways of aggregation were used morphological patterns, and established three clusters: fisiogenic, biogenic and intermediates. The aggregates were analyzed for exchangeable cations, carbon and aggregate stability, soil was analyzed for the exchangeable cations, particle size fractionation of soil organic matter, oxidizable fractions of total organic carbon, particle size analysis and soil macrofauna. In all areas studied, in the dry season, the highest values were quantified aggregate intermediates, while in the rainy season, in general, no differences were observed aggregates formed by different routes in areas except cotton/soybeans. The aggregates showed positive correlation with biogenic carbon and were found in lesser amounts compared to fisiogenic and intermediates. The different types of aggregates formed, besides having different characteristics morphological also differ as to chemical characteristics.

Novas formas de pensar/dizer, dizer/pensar: a imagem como linguagem mediadora da experiência do formador de professores

Pós-graduação em Artes - IA

Espectroscopia de correlação bidimensional generalizada e sample-sample aplicada ao estudo da tripsina pancreática bovina

Pós-graduação em Biofísica Molecular - IBILCE

Investigação comparativa das propriedades estruturais do diboreto de magnésio dopado com compostos de carbono

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Fabricação e caracterização de filmes finos e ultrafinos de coroas de éter com azobenzeno incorporado e estudo da birrefringência fotoinduzida

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Abordagem matemática de roll waves em escoamentos hiperconcentrados com superfície livre

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do ácido zoledrônico usado no tratamento de dentes reimplantados tardiamente: estudo em ratos

Pós-graduação em Odontologia - FOA

Tumor venéreo transmissível espontâneo canino: a inserção do transposon line-1 no gene C-MYC e os critérios de malignidade

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A manifestação dos saberes docentes na prática pedagógica de professores de educação física iniciantes e experientes

Pós-graduação em Educação - IBRC