Filmes nanoestruturados de fosfolipídios como sistemas miméticos de membrana biológica para aplicação em sensores via sers e espectroscopia de impedância

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

Absorção e translocação de boro em cafeeiro

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

A comunicação em Matemática na sala de aula: obstáculos de natureza metodológica na educação de alunos surdos

A pesquisa tem como premissa fundamental analisar situações de ensino de matemática com o conteúdo de problemas multiplicativos classificados com base em Huete e Bravo (2006) mediante a prática docente de professores (surdos e ouvintes) com alunos surdos, buscando indicativos de obstáculos metodológicos que podem estar presentes no processo de comunicação matemática em situações de ensino envolvendo estes sujeitos. Como eixo norteador da pesquisa, buscamos um referencial teórico que embasa o processo de ensino e aprendizagem para surdos com ênfase na especificidade do ensino de matemática que tem como veículo propulsionador a Língua Brasileira de Sinais (LIBRAS), procuramos suscitar reflexões acerca de quais condições devem sustentar este ensino. A pesquisa é de natureza exploratória descritiva e foi realizada em uma Unidade Especializada na educação de surdos. Os registros foram feitos através de filmagens. Os dados foram analisados a partir da perspectiva dos elementos didáticos e pedagógicos, presentes nas ações dos sujeitos de pesquisa e que contribuíram para a obstaculização ou sucesso do ensino e aprendizagem do conteúdo envolvido. A partir de nossas análises podemos considerar que o ensino de matemática para surdos exige do profissional envolvido competências que passam por um amplo domínio de LIBRAS, Matemática, Língua Portuguesa e estratégias de ensino específicas.

A capacitação de servidores técnico-administrativos: desenvolvendo na UFPA competências por meio do conhecimento

Para enfrentar os desafios do novo milênio, as instituições, organizações e de modo geral o mundo do trabalho, deverão preocupar-se mais com as pessoas, investindo, sobretudo, no seu bem-estar, sua realização pessoal e profissional, por meio da capacitação e qualificação, sendo o conhecimento considerado a mola mestre do desenvolvimento. Este estudo tem como objetivo geral investigar se a capacitação dos servidores Técnico-Administrativos (TA) da Universidade Federal do Pará (UFPA) que realizaram os cursos de Especialização em Administração Estratégica e Gestão de Pessoas, no período de 2002 a 2004, na UFPA, Campus de Belém, contribuiu para a melhoria do desempenho de suas unidades por meio do conhecimento adquirido. A partir da metodologia de pesquisa bibliográfica e pesquisa de campo, tem-se a apresentação da fundamentação teórica acerca da temática sob estudo, tendo como base a abordagem qualitativa, utilizando para coleta de dados, documentos e a entrevista. Teve como informantes gestores das Pró-Reitorias de Planejamento (PROPLAN) e Pró-Reitoria de Desenvolvimento e Gestão de Pessoal (PROGEP) que atuaram durante o período da pesquisa, e ainda, quinze servidores técnicos egressos dos cursos de especialização. Para interpretação dos dados foi utilizada a análise de conteúdo, possibilitando uma melhor interpretação das falas dos entrevistados, cujo resultado indica que os referidos cursos se constituíram em premente necessidade para o quadro dos servidores técnico-administrativos, a partir de um processo de Educação Continuada visando um melhor desempenho das atividades laborais, além de maior satisfação e motivação para o trabalho, concluindo-se que a UFPA, como um centro de prestação de serviços públicos educacionais destinados ao cidadão, deve primar por uma política efetiva e continuada de profissionalização e valorização de seu servidor, observando-se que o conhecimento é ferramenta essencial na política de recursos humanos dos servidores para gerar competência, tendo em vista que a própria UFPA se beneficia na medida em que a profissionalização e a valorização do servidor têm apresentado como resultado maior eficiência na prestação dos serviços direcionados a sociedade, objetivo primeiro das instituições governamentais.

Sistema integrado para o planejamento e gestão de recursos hídricos no Município de Lençóis Paulista – SP

Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

Estudo urbano e ambiental da circulação urbana do bairro de Santo Amaro, cidade de São Paulo

This work is resulted of studies about the urban circulation in the modern cities. It was developed from two case studies: the city of São Paulo, specifically Santo Amaro's neighborhood and the city of Regensburg in Germany. The urban circulation of these places was analyzed starting from the premise that the daily of the inhabitants is a relevant factor to be considered. It was researched the types of transportation, the accessibility, and the clearance of public transportations. One of the main purposes of this work was to present general guidelines for the improvement urban circulation in the modern cities, as well as to supply didactic material that contribute to the reflection about urban circulation focusing priorly on the problems of traffic of driving force vehicles

Formalismo canônico da mecânica clássica: alicerce da mecânica quântica

We present a succinct review of the canonical formalism of classical mechanics, followed by a brief review of the main representations of quantum mechanics. We emphasize the formal similarities between the corresponding equations. We notice that these similarities contributed to the formulation of quantum mechanics. Of course, the driving force behind the search of any new physics is based on experimental evidence

Fadiga em compósitos 5HS carbono/epóxi processados via RTM: relação entre cargas axiais no plano e modos de delaminação

Pós-graduação em Engenharia Mecânica - FEG

Das terras do Sem Fim aos Territórios do Agrohidronegócio: conflitos por terra e água no vale do São Francisco

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

Stability of Order in Solvent-Annealed Block Copolymer Thin Films

ABSTRACT: One way to produce high order in a block copolymer thin film is by solution casting a thin film and slowly evaporating the solvent in a sealed vessel. Such a solvent-annealing process is a versatile method to produce a highly ordered thin film of a block copolymer. However, the ordered structure of the film degrades over time when stored under ambient conditions. Remarkably, this aging process occurs in mesoscale thin films of polystyrene-polyisoprene triblock copolymer where the monolayer of vitrified 15 nm diameter polystyrene cylinders sink in a 20 nm thick film at 22 °C. The transformation is studied by atomic force microscopy (AFM). We describe the phenomena, characterize the aging process, and propose a semiquantitative model to explain the observations. The residual solvent effects are important but not the primary driving force for the aging process. The study may lead to effective avenue to improve order and make the morphology robust and possibly the solvent-annealing process more effective.

Describing fatigue crack growth and load ratio effects in Al 2524 T3 alloy with an enhanced exponential model

The fatigue crack behavior in metals and alloys under constant amplitude test conditions is usually described by relationships between the crack growth rate da/dN and the stress intensity factor range Delta K. In the present work, an enhanced two-parameter exponential equation of fatigue crack growth was introduced in order to describe sub-critical crack propagation behavior of Al 2524-T3 alloy, commonly used in aircraft engineering applications. It was demonstrated that besides adequately correlating the load ratio effects, the exponential model also accounts for the slight deviations from linearity shown by the experimental curves. A comparison with Elber, Kujawski and "Unified Approach" models allowed for verifying the better performance, when confronted to the other tested models, presented by the exponential model. (C) 2012 Elsevier Ltd. All rights reserved.

Tailoring Molecular Architectures with Cobalt Tetrasulfonated Phthalocyanine: Immobilization in Layer-by-Layer Films and Sensing Applications

In the field of organic thin films, manipulation at the nanoscale can be obtained by immobilization of different materials on platforms designed to enhance a specific property via the layer-by-layer technique. In this paper we describe the fabrication of nanostructured films containing cobalt tetrasulfonated phthalocyanine (CoTsPc) obtained through the layer-by-layer architecture and assembled with linear poly(allylamine hydrochloride) (PAH) and poly(amidoamine) dendrimer (PAMAM) polyelectrolytes. Film growth was monitored by UV-vis spectroscopy following the Q band of CoTsPc and revealed a linear growth for both systems. Fourier transform infrared (FTIR) spectroscopy showed that the driving force keeping the structure of the films was achieved upon interactions of CoTsPc sulfonic groups with protonated amine groups present in the positive polyelectrolyte. A comprehensive SPR investigation on film growth reproduced the deposition process dynamically and provided an estimation of the thicknesses of the layers. Both FTIR and SPR techniques suggested a preferential orientation of the Pc ring parallel to the substrate. The electrical conductivity of the PAH films deposited on interdigitated electrodes was found to be very sensitive to water vapor. These results point to the development of a phthalocyanine-based humidity sensor obtained from a simple thin film deposition technique, whose ability to tailor molecular organization was crucial to achieve high sensitivity.

Counter-ion effect on surfactant-DNA gel particles as controlled DNA delivery systems

The ability to entrap drugs within vehicles and subsequently release them has led to new treatments for a number of diseases. Based on an associative phase separation and interfacial diffusion approach, we developed a way to prepare DNA gel particles without adding any kind of cross-linker or organic solvent. Among the various agents studied, cationic surfactants offered particularly efficient control for encapsulation and DNA release from these DNA gel particles. The driving force for this strong association is the electrostatic interaction between the two components, as induced by the entropic increase due to the release of the respective counter-ions. However, little is known about the influence of the respective counter-ions on this surfactant-DNA interaction. Here we examined the effect of different counter-ions on the formation and properties of the DNA gel particles by mixing DNA (either single-(ssDNA) or double-stranded (dsDNA)) with the single chain surfactant dodecyltrimethylammonium (DTA). In particular, we used as counter-ions of this surfactant the hydrogen sulfate and trifluoromethane sulfonate anions and the two halides, chloride and bromide. Effects on the morphology of the particles obtained, the encapsulation of DNA and its release, as well as the haemocompatibility of these particles are presented, using counter-ion structure and DNA conformation as controlling parameters. Analysis of the data indicates that the degree of counter-ion dissociation from the surfactant micelles and the polar/hydrophobic character of the counter-ion are important parameters in the final properties of the particles. The stronger interaction with amphiphiles for ssDNA than for dsDNA suggests the important role of hydrophobic interactions in DNA.

Linking origin of the electric field-assisted beta-PbF2 crystallization in lead oxyfluoroborate glasses below T (g) to simultaneous cathode/anode-compensated electrochemical reactions

Full validation of the electrochemical mechanisms so far postulated as driving force of electric field-assisted non-spontaneous crystallization development in given glasses has suffered experimental restrictions. In this work, we looked into origin of this phenomenon in lead oxyfluoroborate glasses, resulting in beta-PbF2 growth even below the corresponding glass transition temperatures, through achieving a systematic study of not only Pt,Ag/Glass/Ag,Pt- but also Pt,Ag/Glass/YSZ:PbF2/Ag,Pt-type cells, where YSZ:PbF2 represents a two-phase system (formed by Y2O3-doped ZrO2 and PbF2). It is demonstrated that crystallization induction in these glasses involves Pb2+ ions reduction at the cathode, the phenomenon being, however, confirmed only when the F- ions were simultaneously also able to reach the anode for oxidation, after assuring either a direct glass-anode contact or percolation pathways for free fluoride migration across the YSZ:PbF2 mixtures. A further support of this account is that the electrochemically induced beta-PbF2 phase crystallizes showing ramified-like microstructure morphology that arises, accordingly, from development of electroconvective diffusion processes under electric field action.

Spark Plasma Sintering of Si3N4-based Ceramics : Sintering mechanism-Tailoring microstructure-Evaluationg properties

Spark Plasma Sintering (SPS) is a promising rapid consolidation technique that allows a better understanding and manipulating of sintering kinetics and therefore makes it possible to obtain Si3N4-based ceramics with tailored microstructures, consisting of grains with either equiaxed or elongated morphology. The presence of an extra liquid phase is necessary for forming tough interlocking microstructures in Yb/Y-stabilised α-sialon by HP. The liquid is introduced by a new method, namely by increasing the O/N ratio in the general formula RExSi12-(3x+n)Al3x+nOnN16-n while keeping the cation ratios of RE, Si and Al constant. Monophasic α-sialon ceramics with tailored microstructures, consisting of either fine equiaxed or elongated grains, have been obtained by using SPS, whether or not such an extra liquid phase is involved. The three processes, namely densification, phase transformation and grain growth, which usually occur simultaneously during conventional HP consolidation of Si3N4-based ceramics, have been precisely followed and separately investigated in the SPS process. The enhanced densification is attributed to the non-equilibrium nature of the liquid phase formed during heating. The dominating mechanism during densification is the enhanced grain boundary sliding accompanied by diffusion- and/or reaction-controlled processes. The rapid grain growth is ascribed to a dynamic ripening mechanism based on the formation of a liquid phase that is grossly out of equilibrium, which in turn generates an extra chemical driving force for mass transfer. Monophasic α-sialon ceramics with interlocking microstructures exhibit improved damage tolerance. Y/Yb- stabilised monophasic α-sialon ceramics containing approximately 3 vol% liquid with refined interlocking microstructures have excellent thermal-shock resistance, comparable to the best β-sialon ceramics with 20 vol% additional liquid phase prepared by HP. The obtained sialon ceramics with fine-grained microstructure show formidably improved superplasticity in the presence of an electric field. The compressive strain rate reaches the order of 10-2 s-1 at temperatures above 1500oC, that is, two orders of magnitude higher than that has been realised so far by any other conventional approaches. The high deformation rate recorded in this work opens up possibilities for making ceramic components with complex shapes through super-plastic forming.