Intensification Of Bioactive Compounds Extraction From Medicinal Plants Using Ultrasonic Irradiation.

Extraction processes are largely used in many chemical, biotechnological and pharmaceutical industries for recovery of bioactive compounds from medicinal plants. To replace the conventional extraction techniques, new techniques as high-pressure extraction processes that use environment friendly solvents have been developed. However, these techniques, sometimes, are associated with low extraction rate. The ultrasound can be effectively used to improve the extraction rate by the increasing the mass transfer and possible rupture of cell wall due the formation of microcavities leading to higher product yields with reduced processing time and solvent consumption. This review presents a brief survey about the mechanism and aspects that affecting the ultrasound assisted extraction focusing on the use of ultrasound irradiation for high-pressure extraction processes intensification.888-9

Concepções alternativas dos alunos sobre ligação metálica

Nesse estudo investigou-se as concepções alternativas de alunos de uma disciplina do curso de licenciatura em química sobre a temática ligação metálica. A investigação foi realizada através da aplicação de um questionário que envolveu aspectos microscópico, macroscópico e representacional do conhecimento químico sobre ligação metálica. Os resultados obtidos mostraram que os alunos apresentaram ideias diferentes daquelas aceitas pela comunidade científica e algumas dessas ideias foram similares às encontradas em estudos internacionais sobre esse tema em níveis distintos de escolaridade

Optimization and economic evaluation of pressurized liquid extraction of phenolic compounds from jabuticaba skins

AbstractThe optimization of the extraction of anthocyanins and other phenolic compounds from jabuticaba skins, a promising Brazilian source of these compounds, was studied using pressurized liquid extraction (PLE). An optimization study was performed using ethanol as a solvent and with extraction pressure (5–10MPa), temperature (313–393K) and static extraction time (3–15min) as independent variables. The optimum PLE conditions for all response variables were estimated; however, PLE conditions resulting in the highest recovery of anthocyanins (5MPa, 553K and 9min of static extraction time) were chosen for comparison with a conventional low-pressure solvent extraction (LPSE). The attributes compared were yield, content of anthocyanins and phenolic compounds and economic feasibility. Similar extraction yields were obtained by LPSE and PLE under optimized conditions; however 2.15 and 1.66-fold more anthocyanins and total phenolic compounds, respectively, were extracted using PLE, while the cost of manufacturing (COM) obtained for the PLE extract was 40-fold lower

Factors Associated with Pre-drinking Among Nightclub Patrons in the City of São Paulo

Aims: the aim of the study was to describe the phenomenon of pre-drinking (alcohol consumption before entering nightclubs or bars) and to identify factors associated with pre-drinking practices among patrons in the city of São Paulo, Brazil. Methods: Individual-level data were collected by a portal survey of 2422 patrons at the entrance and at the exit of 31 nightclubs. the nightclubs were selected by two-stage sampling using a probability proportional to the establishments' capacity in the first stage and a systematic sample of patrons in the second stage. Breath alcohol concentration (BrAC) was measured. Face-to-face interview identified pre-drinking characteristics and past-year risk behaviors. Analysis used sample weights to compensate for nightclubs or patrons that were possibly over- or under-represented. Results: of the study participants, 41.3% (95% confidence interval (CI) = 33.7-49.3) engaged in pre-drinking on the night of the interview. Being male (odds ratio (OR) = 1.98, 95% CI = 1.45-2.71), past-year binge drinking (OR = 2.28, 95% CI = 1.70-3.07), previous episodes of severe effects from drunkenness (OR = 1.77, 95% CI = 1.40-2.22) and sexual risk behavior (OR = 1.67, 95% CI = 1.20-2.33) were associated with recent pre-drinking. Pre-drinking predicted higher BrACs at the nightclub exit. Conclusion: Pre-drinking is prevalent among nightclub patrons and associated with risk behaviors, and is associated with alcohol intoxication at nightclub exits. Environmental prevention strategies must consider pre-drinking as a potential risk factor for alcohol intoxication in nightclubs.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Dept Prevent Med, Epidemiol Sect, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Informat Hlth, Sect Stat, São Paulo, BrazilUniversidade Federal de São Paulo, Sect Bioestat, Dept Prevent Med, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Prevent Med, Epidemiol Sect, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Informat Hlth, Sect Stat, São Paulo, BrazilUniversidade Federal de São Paulo, Sect Bioestat, Dept Prevent Med, São Paulo, BrazilFAPESP: 2011/51658-0FAPESP: 2012/03832-4Web of Scienc

Bethe ansatz solution of the closed anisotropic supersymmetric U model with quantum supersymmetry

The nested algebraic Bethe ansatz is presented for the anisotropic supersymmetric $U$ model maintaining quantum supersymmetry. The Bethe ansatz equations of the model are obtained on a one-dimensional closed lattice and an expression for the energy is given.Comment: 7 pages (revtex), minor modifications. To appear in Mod. Phys. Lett.

Modelos de elementos finitos de propagação de ondas, dreams e epe_cg - aplicação à marina do lugar de baixo

Descrevem-se dois modelos que resolvem a equação de declive suave, denominados DREAMS e EPE_CG. O modelo DREAMS utiliza a formulação clássica do método dos elementos finitos para resolver a equação de declive suave, o que leva à montagem da matriz global do sistema. O modelo EPE_CG utiliza uma formulação denominada elemento por elemento (EPE), para resolver aquela equação. Neste tipo de formulação EPE, não há a montagem da matriz global do sistema, o que traz grande economia nos requisitos de armazenamento. Ambos os modelos efetuam a refração e difração de ondas marítimas em zonas portuárias e são adequados quer para estudos de agitação, quer de ressonância em portos e zonas abrigadas. Os dois modelos numéricos são aplicados ao estudo de agitação no interior da marina do Lugar de Baixo, situada na costa sul da ilha da Madeira, em Portugal, para várias condições de onda incidente. De modo a avaliar as vantagens e desvantagens de cada um dos modelos na sua aplicação a zonas portuárias, os resultados de ambos os modelos numéricos são comparados em termos do tempo de CPU e memória necessária para as várias condições de teste. Palavras-chave: Zonas portuárias e costeiras; propagação e deformação de ondas; refração-difração e reflexão de onda; método dos elementos finitos; formulação elemento por elemento

Federalismo no Brasil: análise da descentralização financeira da perspectiva das cidades médias

The objective of this paper is to analyze the impacts upon the intermediate size cities of the administrative and fiscal decentralization policy put under way by the Federal Constitution of 1988. By intermediate size cities is meant those ones with urban population in the range 100,000 - 500,000 inhabitants. Our interest in this set of cities lies in the fact that they are the ones with the highest population growth rates in the 1970/96 period. This demographic expansion puts pression on the demand for public social services available in these cities, with no assurance thatthese municipalities will be financially able to expand them. This article adresses to this question using agregated and regional data on financial revenues/expenditures for these cities and their social infraestructure indicators as well. One of the major results is that the metropolitan medium size cities, besides showing high demographic growth rates, are the ones with the smallest social indices and in which, due to thenhigh poverty levels, are consequently the municipalities for which the fiscal extraction is harder