12 resultados para Regular array
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Changes in the oceanic heat storage (HS) can reveal important evidences of climate variability related to ocean heat fluxes. Specifically, long-term variations in HS are a powerful indicator of climate change as HS represents the balance between the net surface energy flux and the poleward heat transported by the ocean currents. HS is estimated from sea surface height anomaly measured from the altimeters TOPEX/Poseidon and Jason 1 from 1993 to 2006. To characterize and validate the altimeter-based HS in the Atlantic, we used the data from the Pilot Research Moored Array in the Tropical Atlantic (PIRATA) array. Correlations and rms differences are used as statistical figures of merit to compare the HS estimates. The correlations range from 0.50 to 0.87 in the buoys located at the equator and at the southern part of the array. In that region the rms differences range between 0.40 and 0.51 x 10(9) Jm(-2). These results are encouraging and indicate that the altimeter has the precision necessary to capture the interannual trends in HS in the Atlantic. Albeit relatively small, salinity changes can also have an effect on the sea surface height anomaly. To account for this effect, NCEP/GODAS reanalysis data are used to estimate the haline contraction. To understand which dynamical processes are involved in the HS variability, the total signal is decomposed into nonpropagating basin-scale and seasonal (HS(l)) planetary waves, mesoscale eddies, and small-scale residual components. In general, HS(l) is the dominant signal in the tropical region. Results show a warming trend of HS(l) in the past 13 years almost all over the Atlantic basin with the most prominent slopes found at high latitudes. Positive interannual trends are found in the halosteric component at high latitudes of the South Atlantic and near the Labrador Sea. This could be an indication that the salinity anomaly increased in the upper layers during this period. The dynamics of the South Atlantic subtropical gyre could also be subject to low-frequency changes caused by a trend in the halosteric component on each side of the South Atlantic Current.
Resumo:
A Co-doped silica film was deposited on the surface of a Si(100) wafer and isothermally annealed at 750 degrees C to form spherical Co nanoparticles embedded in the silica film and a few atomic layer thick CoSi2 nanoplatelets within the wafer. The structure, morphology, and spatial orientation of the nanoplatelets were characterized. The experimental results indicate that the nanoplatelets exhibit hexagonal shape and a uniform thickness. The CoSi2 nanostructures lattice is coherent with the Si lattice, and each of them is parallel to one of the four planes belonging to the {111} crystallographic form of the host lattice. (C) 2012 American Institute of Physics. [doi:10.1063/1.3683493]
Resumo:
Background: The purpose of this study was to estimate the genetic influences on the initiation of cigarette smoking, the persistence, quantity and age-at-onset of regular cigarette use in Brazilian families. Methods: The data set consisted of 1,694 individuals enrolled in the Baependi Heart Study. The heritability and the heterogeneity in genetic and environmental variance components by gender were estimated from variance components approaches, using the SOLAR (Sequential Oligogenic Linkage Analysis Routines) computer package. The mixed-effects Cox model was used for the genetic analysis of the age-at onset of regular cigarette use. Results: The heritability estimates were high (> 50%) for smoking initiation and were intermediate, ranging from 23.4 to 31.9%, for smoking persistence and quantity. Significant evidence for heterogeneity in variance components by gender was observed for smoking initiation and age-at-onset of regular cigarette use. Genetic factors play an important role in the interindividual variation of these phenotypes in females, while in males there is a predominant environmental component, which could be explained by greater social influences in the initiation of tobacco use. Conclusions: Significant heritabilities were observed in smoking phenotypes for both males and females from the Brazilian population. These data add to the literature and are concordant with the notion of significant biological determination in smoking behavior. Samples from the Baependi Heart Study may be valuable for the mapping of genetic loci that modulate this complex biological trait.
Resumo:
de Araujo CC, Silva JD, Samary CS, Guimaraes IH, Marques PS, Oliveira GP, do Carmo LGRR, Goldenberg RC, Bakker-Abreu I, Diaz BL, Rocha NN, Capelozzi VL, Pelosi P, Rocco PRM. Regular and moderate exercise before experimental sepsis reduces the risk of lung and distal organ injury. J Appl Physiol 112: 1206-1214, 2012. First published January 19, 2012; doi:10.1152/japplphysiol.01061.2011.-Physical activity modulates inflammation and immune response in both normal and pathologic conditions. We investigated whether regular and moderate exercise before the induction of experimental sepsis reduces the risk of lung and distal organ injury and survival. One hundred twenty-four BALB/c mice were randomly assigned to two groups: sedentary (S) and trained (T). Animals in T group ran on a motorized treadmill, at moderate intensity, 5% grade, 30 min/day, 3 times a week for 8 wk. Cardiac adaptation to exercise was evaluated using echocardiography. Systolic volume and left ventricular mass were increased in T compared with S group. Both T and S groups were further randomized either to sepsis induced by cecal ligation and puncture surgery (CLP) or sham operation (control). After 24 h, lung mechanics and histology, the degree of cell apoptosis in lung, heart, kidney, liver, and small intestine villi, and interleukin (IL)-6, KC (IL-8 murine functional homolog), IL-1 beta, IL-10, and number of cells in bronchoalveolar lavage (BALF) and peritoneal lavage (PLF) fluids as well as plasma were measured. In CLP, T compared with S groups showed: 1) improvement in survival; 2) reduced lung static elastance, alveolar collapse, collagen and elastic fiber content, number of neutrophils in BALF, PLF, and plasma, as well as lung and distal organ cell apoptosis; and 3) increased IL-10 in BALF and plasma, with reduced IL-6, KC, and IL-1 beta in PLF. In conclusion, regular and moderate exercise before the induction of sepsis reduced the risk of lung and distal organ damage, thus increasing survival.
Resumo:
Fleury Group
Resumo:
We report an efficient alternative to obtain recessed microelectrodes device on gold electrode surface, in which mixed self-assembled monolayer of long and short carbon alkanethiol chains was used for this purpose. Development of the modified electrodes included the chemical adsorption of 11-mercaptoundecanoic acid and 2-mercaptoethanol solution, as well as their mixtures, on gold surface, resulting in the final mixed self-assembled monolayer configuration. For comparison, the electrochemical performance of self-assembled monolayer of 11-mercaptoundecanoic acid. 3-mercaptopropionic acid, 4-mercapto-1-butanol and 6-mercapto-1-hexanol modified electrodes was also investigated. It was verified that, in the mixed self-assembled monolayer, the 11-mercaptoundecanoic acid acts as a barrier for electron transfer while the short alkanethiol chair is deposited in an island-like shape through which electrons can be freely transferred to ions in solution, allowing electrochemical reactions to occur. The performance of the modified electrodes toward microelectrode behavior was investigated via cyclic voltammetry and electrochemical impedance spectroscopy measurements using [Fe(CN)(6)](3-/4-) redox couple as a probe. In this case, sigmoidal voltammetric responses were obtained, very similar to those observed for microelectrodes. Such behavior reinforces the proposition of electron transfer through the short alkanethiol chain layer and surface blockage by the long chain one. Electrochemical impedance results allowed calculated the mean radius value of each microelectrode disks of 3.8 mu m with about 22 mu m interval between them. The microelectrode environment provided by the mixed self-assembled monolayer can be conveniently used to provide an efficient catalytic conversion in biosensing applications. (C) 2012 Elsevier Ltd. All rights reserved.
Resumo:
The association between anisotropic magnetoresistive (AMR) sensor and AC biosusceptometry (ACB) to evaluate gastrointestinal motility is presented. The AMR-ACB system was successfully characterized in a bench-top study, and in vivo results were compared with those obtained by means of simultaneous manometry. Both AMR-ACB and manometry techniques presented high temporal cross correlation between the two periodicals signals (R = 0.9 +/- 0.1; P < 0.05). The contraction frequencies using AMR-ACB were 73.9 +/- 7.6 mHz and using manometry were 73.8 +/- 7.9 mHz during the baseline (r = 98, p < 0.05). The amplitude of contraction using AMR-ACB was 396 +/- 108 mu T.s and using manometry were 540 +/- 198 mmHg.s during the baseline. The amplitudes of signals for AMR-ACB and manometric recordings were similarly increased to 86.4% and 89.3% by neostigmine, and also decreased to 27.2% and 21.4% by hyoscine butylbromide in all animals, respectively. The AMR-ACB array is nonexpensive, portable, and has high-spatiotemporal resolution to provide helpful information about gastrointestinal tract.
Resumo:
The development of polymer-based photovoltaic devices brings the promise of low-cost and lightweight solar energy conversion systems. This technology requires new materials and device architectures with enhanced efficiency and lifetime, which depends on the understanding of charge-transport mechanisms. Organic films combined with electronegative nanoparticles may form systems with efficient dissociation of the photogenerated excitons, thus increasing the number of carriers to be collected by the electrodes. In this paper we investigate the steady-state photoconductive action spectra of devices formed by a bilayer of regio-regular poly(3-hexylthiophene) (RRP3HT) and TiO2 sandwiched between ITO and aluminum electrodes (ITO/TiO2:RRP3HT/Al). Photocurrents were measured for distinct bias voltages with illumination from either side of the device. Heterojunction structures were prepared by spin coating a RRP3HT film on an already deposited TiO2 layer on ITO. Symbatic and antibatic curves were obtained and a model for photocurrent action spectra was able to fit the symbatic responses. The quantum yield increased with the electric field, indicating that exciton dissociation is a field-assisted process as in an Onsager mechanism. Furthermore, the quantum yield was significantly higher when illumination was carried out through the ITO electrode onto which the TiO2 layer was deposited, as the highly electronegative TiO2 nanoparticles were efficient in exciton dissociation.
Resumo:
A inclusão de alunos com necessidades educacionais especiais no ensino regular depende da preparação da comunidade escolar para promover a participação de todos os alunos. Foi objetivo deste estudo conhecer, do ponto de vista do professor do ensino fundamental da rede pública municipal, as estratégias pedagógicas que utilizavam para a inclusão de crianças com deficiência na classe comum. Para isso foram realizadas entrevistas semiestruturadas individuais e, posteriormente, grupais com 11 professores de cinco escolas, um representante do Centro de Formação e Acompanhamento à Inclusão e um coordenador pedagógico. As entrevistas foram gravadas e transcritas. Após diversas leituras foi possível identificar como temáticas principais: sentidos e imaginários do professor sobre a deficiência, formação do professor para efetivação do processo de inclusão, bem como a utilização de estratégias pedagógicas diferenciadas e formação de rede de apoio na escola. Os entrevistados utilizavam estratégias gerais como aula expositiva, debates, e específicas como: avaliação dos alunos, adaptação do material, atividades em duplas, parceria com o professor da sala de apoio e acompanhamento à inclusão. Parte dos entrevistados trouxe uma visão com relação aos alunos com deficiência permeada de possibilidades, acreditando no potencial de aprendizagem dos mesmos, enquanto para outros, o discurso centrou-se, sobretudo, na impossibilidade da aprendizagem. Os docentes identificaram a necessidade de apoio institucional para seu trabalho, incluindo possibilidades de formação a partir das demandas cotidianas. Responder às necessidades levantadas é parte dos desafios para implementar a Educação Inclusiva na perspectiva da Educação para Todos, para a efetivação dos direitos de crianças com necessidades educacionais especiais.
Resumo:
OBJETIVOS: avaliar as modificações na prática de atividade física (AF) e as barreiras para adoção de um estilo de vida saudável em mulheres que receberam orientações nutricionais e de AF durante a gestação e no primeiro ano após o parto. MÉTODOS: estudo de coorte com 57 mulheres (Grupo Controle = 29 e Grupo Intervenção = 28), e idade média igual a 28 (±6) anos. As informações foram obtidas através de entrevistas em visita domiciliar (durante a intervenção) e inquérito telefônico (um ano após o término da intervenção), utilizou-se questionário de AF. Para análise das barreiras foi realizada uma entrevista semiestruturada com questões abertas, as quais foram codificadas e agrupadas para análise dos dados. Foram realizados testes de qui-quadrado, Mann-Whitney U e Friedman. RESULTADOS: aos seis meses, apenas 30% das mulheres do grupo Intervenção realizavam AF no lazer pelo menos 120 minutos por semana, contra 10% do grupo Controle, reduzindo para 18% e 4%, respectivamente, dois anos após o parto. As principais barreiras à prática de AF regular foram: falta de tempo (44%), cuidado com os filhos (37%), trabalho (21%), afazeres domésticos (21%) e comodismo (26%). CONCLUSÕES: futuros programas devem priorizar a aquisição de conhecimento, visando à adoção de um estilo de vida ativo no pós-parto, considerando as barreiras maternas.
Resumo:
OBJETIVOS: Analisar criticamente a inclusão do portador de necessidades especiais no ensino regular brasileiro, considerando aspectos sociais e jurídicos, por meio de revisão de literatura. ESTRATÉGIA DE PESQUISA: A pesquisa bibliográfica foi conduzida em bases de dados de acesso público: LILACS, SciELO, Portal Cochrane e IUSDATA, sendo esta última da Biblioteca da Faculdade de Direito da Universidade de São Paulo, considerando todos os artigos publicados até o mês de dezembro de 2010. Como estratégia de busca foram utilizados os seguintes termos livres: educação inclusiva, educação especial, proposta inclusiva e portador de necessidades especiais. CRITÉRIOS DE SELEÇÃO: Durante a busca, foram avaliados e selecionados apenas os estudos cujo resumo ou corpo do artigo tivesse relação com o objetivo proposto. ANÁLISE DE DADOS : Os artigos potencialmente relevantes para a revisão foram apresentados em uma ficha protocolar contendo critérios de elegibilidade do estudo, métodos utilizados, características do grupo de artigos analisado, tipo de intervenção realizada e resultados obtidos no estudo. Os artigos classificados como opinião de especialistas, apesar de apresentarem baixo nível de evidência científica, foram incluídos no trabalho, pois são frequentemente encontrados na literatura sobre o assunto. RESULTADOS: Foram encontrados 1.399 artigos, e após leitura dos resumos foram selecionados 120 artigos potencialmente relevantes considerando-se o objetivo da pesquisa. Destes, 67 artigos foram citados em mais de uma base de dados, o que resultou em 53 artigos para serem lidos na íntegra. Após a leitura dos 53 artigos, foram excluídos 15 que não se enquadravam nos critérios de inclusão. Desta forma, 38 estudos foram incluídos e analisados. CONCLUSÃO: Após a análise crítica da literatura da área conclui-se que, até o momento, de maneira geral, a escola recebe, mas há muito a percorrer para incluir os alunos portadores de necessidades especiais, embora o país possua o escopo da inclusão. Assim, faz-se necessário o estabelecimento de diretrizes e ações políticas visando uma inclusão efetiva.
Resumo:
We present a new Ultra Wide Band (UWB) Timed- Array Transmitter System with Beamforming capability for high-resolution remote acquisition of vital signals. The system consists of four identical channels, where each is formed of a serial topology with three modules: programmable delay circuit (PDC or τ), a novel UWB 5th Gaussian Derivative order pulse generator circuit (PG), and a planar Vivaldi antenna. The circuit was designed using 0.18μm CMOS standard process and the planar antenna array was designed with filmconductor on Rogers RO3206 substrate. Spice simulations results showed the pulse generation with 104 mVpp amplitude and 500 ps width. The power consumption is 543 μW, and energy consumption 0.27 pJ per pulse using a 2V power supply at a pulse repetition rate (PRR) of 100 MHz. Electromagnetic simulations results, using CST Microwave (MW) Studio 2011, showed the main lobe radiation with a gain maximum of 13.2 dB, 35.5º x 36.7º angular width, and a beam steering between 17º and -11º for azimuthal (θ) angles and 17º and -18º for elevation (φ) angles at the center frequency of 6 GHz