Caracterização de propriedades de vidros polarizados do sistema P2O5 – B2O3 – CaO – TiO2

Pós-graduação em Ciência dos Materiais - FEIS

O papel do mediador técnico-pedagógico na formação continuada a distância de professores em serviço

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

Isolamento passivo de vibrações aleatórias atuantes sobre equipamentos eletrônicos aeronaúticos embarcados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da dilatometria do titânio e das expansões de presa e térmica de revestimentos fosfatados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um projeto de interação Universidade-Escola como espaço formativo para a docência do professor universitário

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

De prático à profissional da matemática: que saberes se constituem em um processo de formação inicial de professores em serviço?

O estudo teve como objetivo investigar as mudanças ocorridas nas/das práticas dos professores-alunos a partir do ingresso em um curso de formação inicial de professores em serviço. Para tal, foi realizada uma pesquisa qualitativa, na modalidade estudo de caso, com dados coletados a partir de entrevistas semi-estruturadas realizada com quatro professores alunos do curso de Licenciatura Plena em Matemática da Universidade Federal do Pará, que estão atuando em sala de aula na Rede Pública Estadual de Ensino. Foram obtidas consideráveis informações que permitiram analisar o entendimento dos sujeitos participantes sobre as mudanças e os saberes construídos e/ou em construção ao longo do curso de formação. Realizamos entrevistas com quatro professores-formadores que estiveram trabalhando com disciplinas especificas da Licenciatura em Matemática na perspectiva de destacar o papel fundamental desse sujeito no processo de formação. Os resultados apontam que, apesar dos fatores que interferem na construção do saber sistematizado, houve mudanças significativas nas/das práticas docentes dos professores-alunos a partir dos saberes construídos num processo de formação inicial. Concluiu-se que estes resultados apontam para a importância da formação inicial para o exercício da prática docente.

Inovação na licenciatura: cartografando uma reforma curricular

Este estudo narrativo centra-se na formação de professores nos cursos de licenciatura, e parte dos elementos que caracterizam e significam o processo de reforma curricular do curso de licenciatura em Ciências Biológicas da Universidade Federal do Pará, ocorrido durante o ano de 2000, no bojo das reformas educativas em curso no cenário brasileiro. Busco, nesse contexto, pela análise reflexiva, investigar para compreender a construção de um conjunto de inovações curriculares na formação inicial de professores de ciências e biologia que atuarão na educação básica do sistema de ensino brasileiro e regional. Tais ações se consubstanciam na apresentação, na discussão e no debate de aspectos internos e externos do referido processo, da proposição e implementação do projeto da reforma para o curso em questão, a partir das vozes de um grupo de professoras que dele participaram, das representações dos alunos contemplados na reforma, e também de documentos pertinentes ao momento. Aponto, de modo particular, avanços significativos no que concerne às mudanças qualitativas empreendidas, as quais são observadas na construção de saberes docentes por parte dos alunos em processo de formação, sendo algo atingível na prática de professores formadores, no âmbito deste curso. Desse modo, o estudo guarda contribuições relevantes na investigação e na reflexão atual no campo da formação inicial de professores de ciências e biologia, de modo particular, e da formação de professores nas demais licenciaturas, de modo geral.

Bancos comunitários de desenvolvimento: o papel da comunicação na economia solidária

O presente estudo tem por objetivo analisar o papel da comunicação voltada para mobilização na economia solidária e no desenvolvimento local, especialmente em Bancos Comunitários de Desenvolvimento (BCDs). A forma de comunicação principal a ser discutida é a em decorrência do Capital Social e de mobilização social, pois a utilização de meios de comunicação de massa não consegue alcançar toda a comunidade em que o Banco atua. Para tanto, o aporte teórico teve como foco a economia solidária e o meio ambiente; comunicação; capital social; e mobilização social. Além disso foram realizadas visitas a dois BCDs em Manaus, o banco Palmas em Fortaleza e o Banco Tupinambá na Baía do Sol em Mosqueiro (Belém), onde uma pesquisa qualitativa com mães cadastradas no Bolsa Família, programa do Governo Federal de ajuda financeira direta a famílias em estado pobreza ou pobreza extrema, participantes do projeto CECI-Mulheres, cujo resultado mostrou que, apesar do projeto existir há um ano, as participantes não tem muito claro os conceitos básicos de Economia Solidária e BCDs – visto que as mulheres que fazem parte dele são agentes formadores de opinião, logo o posicionamento delas dá indícios sobre como a comunidade vê o banco. Como parte da conclusão do trabalho, o diagnóstico realizado sobre os canais de comunicação existentes do Banco Tupinambá ressalta que a comunicação para fora da comunidade é mais frequente e trabalhada do que dentro da comunidade. Dessa forma foram relacionadas sugestões de novos canais de comunicação com foco na mobilização e no crescimento do capital social dentro da comunidade da Baía do Sol.

Second Phase Precipitation in Ultrafine-grained Ferrite Steel

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

Aplicação de cavacos de titânio para produção de revestimentos resistentes ao desgaste

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

Isolation, selection and characterization of root-associated growth promoting bacteria in Brazil Pine (Araucaria angustifolia)

Araucaria angustifolia, a unique species of this genus that occurs naturally in Brazil, has a high socio-economic and environmental value and is critically endangered of extinction, since it has been submitted to intense predatory exploitation during the last century. Root-associated bacteria from A. angustifolia were isolated, selected and characterized for their biotechnological potential of growth promotion and biocontrol of plant pathogenic fungi. Ninety-seven strains were isolated and subjected to chemical tests. All isolates presented at least one positive feature, characterizing them as potential PGPR. Eighteen isolates produced indole-3-acetic acid (IAA), 27 were able to solubilize inorganic phosphate, 21 isolates were presumable diazotrophs, with pellicle formation in nitrogen-free culture medium, 83 were phosphatases producers, 37 were positive for siderophores and 45 endospore-forming isolates were antagonistic to Fusarium oxysporum, a pathogen of conifers. We also observed the presence of bacterial strains with multiple beneficial mechanisms of action. Analyzing the fatty acid methyl ester (FAME) and partial sequencing of the 16S rRNA gene of these isolates, it was possible to characterize the most effective isolates as belonging to Bacillaceae (9 isolates), Enterobacteriaceae (11) and Pseudomonadaceae (1). As far as we know, this is the first study to include the species Ewingella americana as a PGPR. (C) 2011 Elsevier GmbH. All rights reserved.

Quantification of Short and Medium Range Order in Mixed Network Former Glasses of the System GeO2-NaPO3: A Combined NMR and X-ray Photoelectron Spectroscopy Study

Glasses in the system xGeO(2)-(1-x)NaPO3 (0 <= x <= 0.50) were prepared by conventional melting quenching and characterized by thermal analysis, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and P-31 nuclear magnetic resonance (MAS NMR) techniques. The deconvolution of the latter spectra was aided by homonuclear J-resolved and refocused INADEQUATE techniques. The combined analyses of P-31 MAS NMR and O-1s XPS lineshapes, taking charge and mass balance considerations into account, yield the detailed quantitative speciations of the phosphorus, germanium, and oxygen atoms and their respective connectivities. An internally consistent description is possible without invoking the formation of higher-coordinated germanium species in these glasses, in agreement with experimental evidence in the literature. The structure can be regarded, to a first approximation, as a network consisting of P-(2) and P-(3) tetrahedra linked via four-coordinate germanium. As implied by the appearance of P-(3) units, there is a moderate extent of network modifier sharing between phosphate and germanate network formers, as expressed by the formal melt reaction P-(2) + Ge-(4) -> P-(3) + Ge-(3). The equilibrium constant of this reaction is estimated as K = 0.52 +/- 0.11, indicating a preferential attraction of network modifier by the phosphorus component. These conclusions are qualitatively supported by Raman spectroscopy as well as P-31{Na-23} and P-31{Na-23} rotational echo double resonance (REDOR) NMR results. The combined interpretation of O-1s XPS and P-31 MAS NMR spectra shows further that there are clear deviations from a random connectivity scenario: heteroatomic P-O-Ge linkages are favored over homoatomic P-O-P and Ge-O-Ge linkages.

Effects of habitat characteristics on cryptic fish assemblages

Habitat structure is known to influence the abundance of fishes on temperate reefs. Biotic interactions play a major role in determining the distribution and abundance of species. The significance of these forces in affecting the abundance of fishes may hinge on the presence of organisms that either create or alter habitat. On temperate reefs, for example, macroalgae are considered autogenic ecosystem engineers because they control resource availability to other species through their physical structure and provide much of the structure used by fish. On both coral and temperate reefs, small cryptic reef fishes may comprise up to half of the fish numbers and constitute a diverse community containing many specialized species. Small cryptic fishes (<100 mm total length) may be responsible for the passage of 57% of the energy flow and constitute ca. 35% of the overall reef fish biomass on coral reefs. These benthic fish exploit restricted habitats where food and shelter are obtained in, or in relation to, conditions of substrate complexity and/or restricted living space. A range of mechanisms has been proposed to account for the diversity and the abundance of small fishes: (1) lifehistory strategies that promote short generation times, (2) habitat associations and behaviour that reduce predation and (3) resource partitioning that allows small species to coexist with larger competitors. Despite their abundance and potential importance within reef systems, little is known of the community ecology of cryptic fishes. Specifically on habitat associations many theories suggested a not clear direction on this subject. My research contributes to the development of marine fish ecology by addressing the effects of habitat characteristics upon distribution of cryptobenthic fish assemblages. My focus was on the important shallow, coastal ecosystems that often serve as nursery habitat for many fish and where different type of habitat is likely to both play important roles in organism distribution and survival. My research included three related studies: (1) identification of structuring forces on cryptic fish assemblages, such as physical and biological forcing; (2) macroalgae as potential tools for cryptic fish and identification of different habitat feature that could explain cryptic fish assemblages distribution; (3) canopy formers loss: consequences on cryptic fish and relationship with benthos modifications. I found that: (1) cryptic fish assemblages differ between landward and seaward sides of coastal breakwaters in Adriatic Sea. These differences are explained by 50% of the habitat characteristics on two sides, mainly due to presence of the Codium fragile, sand and oyster assemblages. Microhabitat structure influence cryptic fish assemblages. (2) Different habitat support different cryptic fish assemblages. High heterogeneity on benthic assemblages reflect different fish assemblages. Biogenic components that explain different and diverse cryptic fish assemblages are: anemonia bed, mussel bed, macroalgal stands and Cystoseira barbata, as canopy formers. (3) Canopy forming loss is not relevant in structuring directly cryptic fish assemblages. A removal of canopy forming algae did not affect the structure of cryptic fish assemblages. Canopy formers algae on Conero cliff, does not seem to act as structuring force, probably due to its regressive status. In conclusion, cryptic fish have been shown to have species-specific associations with habitat features relating to the biological and non biological components afforded by fish. Canopy formers algae do not explain cryptic fish assemblages distribution and the results of this study and information from the literature (both from the Mediterranean Sea and elsewhere) show that there are no univocal responses of fish assemblages. Further exanimations on an non regressive status of Cystoseira canopy habitat are needed to define and evaluate the relationship between canopy formers and fish on Mediterranean sea.

Biofilm formation by the anaerobic pathogen Clostridium difficile

Clostridium difficile is an obligate anaerobic, Gram-positive, endospore-forming bacterium. Although an opportunistic pathogen, it is one of the important causes of healthcare-associated infections. While toxins TcdA and TcdB are the main virulence factors of C. difficile, the factors or processes involved in gut colonization during infection remain unclear. The biofilm-forming ability of bacterial pathogens has been associated with increased antibiotic resistance and chronic recurrent infections. Little is known about biofilm formation by anaerobic gut species. Biofilm formation by C. difficile could play a role in virulence and persistence of C. difficile, as seen for other intestinal pathogens. We demonstrate that C. difficile clinical strains, 630, and the strain isolated in the outbreak, R20291, form structured biofilms in vitro. Biofilm matrix is made of proteins, DNA and polysaccharide. Strain R20291 accumulates substantially more biofilm. Employing isogenic mutants, we show that virulence-associated proteins, Cwp84, flagella and a putative quorum sensing regulator, LuxS, Spo0A, are required for maximal biofilm formation by C. difficile. Moreover we demonstrate that bacteria in C. difficile biofilms are more resistant to high concentrations of vancomycin, a drug commonly used for treatment of CDI, and that inhibitory and sub-inhibitory concentrations of the same antibiotic induce biofilm formation. Surprisingly, clinical C. difficile strains from the same out-break, but from different origin, show differences in biofilm formation. Genome sequence analysis of these strains showed presence of a single nucleoide polymorphism (SNP) in the anti-σ factor RsbW, which regulates the stress-induced alternative sigma factor B (σB). We further demonstrate that RsbW, a negative regulator of alternative sigma factor B, has a role in biofilm formation and sporulation of C. difficile. Our data suggest that biofilm formation by C. difficile is a complex multifactorial process and may be a crucial mechanism for clostridial persistence in the host.

Exploring the biofilm of Streptococcus agalactiae to identify virulence factors

Streptococcus agalactiae, also known as Group B Streptococcus (GBS) is the primary colonizer of the anogenital mucosa of up to 40% of healthy women and an important cause of invasive neonatal infections worldwide. Among the 10 known capsular serotypes, GBS type III accounts for 30-76% of the cases of neonatal meningitis. Biofilms are dense aggregates of surface-adherent microorganisms embedded in an exopolysaccharide matrix. Centers for Disease Control and Prevention estimate that 65% of human bacterial infections involve biofilms (Post et al., 2004). In recent years, the ability of GBS to form biofilm attracted attention for its possible role in fitness and/or virulence. Here, a new in vitro biofilm formation protocol was developed to guarantee more stringent conditions, to better discriminate between strong-, low- and non- biofilm forming strains and reduce ambiguous data interpretation. This protocol was applied to screen the in vitro biofilm formation ability of more than 350 GBS clinical isolates from pregnant women and neonatal infections belonging to different serotype, in relation to media composition and pH. The results showed the enhancement of GBS biofilm formation in acidic condition and identified a subset of isolates belonging to serotypes III and V that forms strong biofilms in these conditions. Interestingly, the best biofilm formers belonged to the serotype III hypervirulent clone ST-17.It was also found that pH 5.0 induces down-regulation of the capsule but that this reduction is not enough by itself to ensure biofilm formation. Moreover, the ability of proteinase K to strongly inhibit biofilm formation and to disaggregate mature biofilms suggested that proteins play an essential role in promoting GBS biofilm formation and contribute to the biofilm structural stability. Finally, a set of proteins potentially expressed during the GBS in vitro biofilm formation were identified by mass spectrometry.