Efeitos das cardioplegias sangüínea e cristalóide no miocárdio hipertrófico de coelho: avaliação estrutural e ultra-estrutural

OBJETIVO: Comparar e avaliar experimentalmente as alterações estruturais e ultra-estruturais em corações hipertrofiados isolados de coelhos submetidos à parada protegida pela solução de cardioplegia sangüínea e cardioplegia cristalóide. MÉTODO: O estudo compreendeu um grupo controle e dois grupos experimentais. No grupo I, a parada cardíaca foi obtida pela infusão da solução de cardioplegia sangüínea contínua e tépida. No grupo II, a parada cardíaca foi conseguida pela infusão da solução de cardioplegia cristalóide intermitente e fria. No grupo controle, os corações foram submetidos à parada anóxia normotérmica por 45 minutos. Após experimentos, oito amostras da parede lateral do ventrículo esquerdo foram coletadas e fixadas em formaldeído 10% e glutaraldeído 2,5% para análises estrutural e ultra-estrutural. RESULTADOS: Os resultados estruturais e as descrições ultra-estruturais mostraram que os corações submetidos à parada protegida pela cardioplegia sangüínea contínua e tépida (grupo I) estavam mais preservados com alterações celulares menos acentuadas se comparados aos submetidos à parada protegida pela cardioplegia cristalóide intermitente e fria (grupo II) e ao grupo controle. CONCLUSÃO: A cardioplegia sangüínea contínua e tépida (Grupo I) foi mais eficiente na preservação da integridade estrutural e ultra-estrutural do miocárdio, quando comparada à cardioplegia cristalóide intermitente e fria (Grupo II).

Metodologia para identificação do componente fundamental da tensão da rede baseada no algoritmo recursivo da TDF

Considerando a crescente utilização de técnicas de processamento digital de sinais em aplicações de sistemas eletrônicos e ou de potência, este artigo discute o uso da Transformada Discreta de Fourier Recursiva (TDFR) para identificação do ângulo de fase, da freqüência e da amplitude das tensões fundamentais da rede, independente de distorções na forma de onda ou de transitórios na amplitude. Será discutido que, se a freqüência fundamental das tensões medidas coincide com a freqüência a qual a TDF foi projetada, um simples algoritmo TDFR é completamente capaz de fornecer as informações requeridas de fase, freqüência e amplitude. Dois algoritmos adicionais são propostos para garantir seu desempenho correto quando a freqüência difere do seu valor nominal: um deles para a correção do erro de fase do sinal de saída e outro para identificação da amplitude do componente fundamental. Além disto, destaca-se que através dos algoritmos propostos, independentemente do sinal de entrada, a identificação do componente fundamental pode ser realizada em, no máximo, 2 ciclos da rede. Uma análise dos resultados evidenciados pela TDFR foi desenvolvida através de simulações computacionais. Também serão apresentados resultados experimentais referentes ao sincronismo de um gerador síncrono com a rede elétrica, através dos sinais fornecidos pela TDFR.

Algoritmo baseado em afundamentos de tensão para localização de faltas em alimentadores de distribuição de energia elétrica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Desenvolvimento de varistores à base de SnO2 para aplicação em redes de alta tensão

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

Caracterização estrutural da cerâmica Ti x(Sm0,2Ce0,8)1-xO 2-delta pelo método de Rietveld

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

Influência da pós-carga sobre a taxa de variação da tensão desenvolvida (dT/dt). Estudo em músculo cardíaco isolado.

PURPOSE: To evaluate the effects of afterload on peak rate of tension rise (dT/dt) in the isolated muscle. METHODS: Left ventricular papillary muscles from Wistar rats were studied in isometric and isotonic afterloaded contractions. Muscles were analised in Krebs-Henseleit solution with calcium concentration of 2.52mM at 28 degrees C. The resting muscle length (preload) was maintained constant. The peak isometric developed tension (DT) and dT/dt were measured during increases of afterload (25, 50, 75 and 100% from DT). RESULTS: A rise in afterload corresponding to 50, 75 and 100% of DT, did not cause an increase in dT/dt values (p > 0.05). The dT/dt value decreased (p < 0.05) when afterload was changed from 75% to 25% of DT. CONCLUSION: The data suggest that an increase in the afterload from 50% of the DT did not promote changes in the dT/dt.

Mapeamento do contorno estrutural do embasamento da bacia sedimentar de Curitiba - PR

The sedimentary Curitiba basin is located in the Central-Southern part of the first Parananense plateau, and comprises Curitiba (PR), and part of the neighbour Municipalities (fig.1). It is supposed to be of Plio-Pleistocene age. It has a shallow sedimentary fulfillment, represented by the Guabirotuba formation (BIGARELLA and SALAMUNI, 1962) which is dristributed over a large area of about 3.000km2. The internal geometry, not entirely known yet, is actually object of detailed research, that shows its geological evolution to Cenozoic tectonic movements. For the purpose of this study the definition of the structural contour of the basement and their depo-centers is fundamental. This paper presents the results of the integration of surface and subsurface data, processed by statistical methods, which allowed a more precise definition of the morphostructural framework of the basement. For the analysis of the geological spacial data, specific softwares were used for statistical processing for trend surfaces analysis. The data used in this study are of following types: a) drilling logs for ground water; b) description of surface points of geological maps (CRPM, 1977); c) description of points of geotechnical drillings and down geological survey. The data of 223 drilling logs for ground water were selected out of 770 wells. The description files of 700 outcrops, as well as planialtimetric field data, were used for the localization of the basement outcrop. Thus, a matrix with five columns was set up: utm E-W (x) and utm N-S (y); surface altitude (z); altimetric cote of the contact between sedimentary rocks and the basement (k); isopachs (l). For the study of the basement limits, the analysis of surface trends of 2(nd) and 3(rd) degree polinomial for the altimetric data (figs. 2 and 3) were used. For the residuals the method of the inverse of the square of the distance (fig.4) was used. The adjustments and the explanations of the surfaces were made with the aid of multiple linear regressions. The analysis of 3rd degree polinomial trend surface (fig.3) confirmed that the basement tends to be more exposed towards NNW-SSE explaining better the data trend through an ellipse, which striking NE-SW and dipping SW axis coincides with the trough of the basin observed in the trending surface of the basement. The performed analysis and the respective images offer a good degree of certainty of the geometric model of the Curitiba Basin and of the morphostructure of its basement. The surface trend allows to sketch with a greater degree of confidence the structural contour of the topgraphic surface (figs. 5 and 6) and of the basement (figs. 7 and 8), as well as the delimitation of intermediate structural heights, which were responsible for isolated and assymmetric depocenters. These details are shown in the map of figures 9 and 10. Thus, the Curitiba Basin is made up by a structural trough stretching NE-SW, with maximum preserved depths of about 80m, which are separated by heights and depocenters striking NW-SE (fig. 11). These structural features seems to have been controlled by tectonic reactivation during the Tertiary (HASUI, 1990) and which younger dissection was conditioned by neotectonic processes (SALAMUNI and EBERT, 1994).

Análise estrutural e aspectos do mosaico sucessional de uma floresta semidecídua em Botucatu, SP

The objective of the present paper was to study the structure of a semi-deciduous forest. The main purpose was to verify if the floristic composition and/or structure is influenced by the mosaic developmental phase. The study has been done in 200 plots, each one measuring 10 × 10 m, forming a grid of 200m × 100 m in the center of the forest fragment. In to separate the study area in units representing different phases of forest mosaic (gap, construction and mature), the plots were classified by cluster analysis based on structural traits. The species with the highest influence the community structure were Aspidosperma polyneuron, Trichilia claussenii and Trichilia catigua.Gap, construction and mature phases presented different patterns in spite of the three species influence.

Caracterização textural e estrutural de V 2O 5/TiO 2 obtidos via sol-gel: Comparação entre secagem convencional e supercrítica

This work describes a modified sol-gel method for the preparation of V 2O 5/TiO 2 catalysts. The samples have been characterized by N 2 adsorption at 77K, x-ray diffractometry (XRD) and Fourier Transform Infrared (FT-IR). The surface area increases with the vanadia loading from 24 m 2 g -1, for pure TiO 2, to 87 m 2 g -1 for 9wt.% of V 2O 5. The rutile form is predominant for pure TiO 2 but became enriched with anatase phase when vanadia loading is increased. No crystalline V 2O 5 phase was observed in the catalysts diffractograms. Two species of surface vanadium observed by FT-IR spectroscopy a monomeric vanadyl and polymeric vanadates, the vanadyl/vanadate ratio remains practically constant.

A Influência da Referência de Tensão na Avaliação de Indicadores de Qualidade de Energia

This paper discusses the importance of the voltage referential for power quality monitoring and power systempsilas instrumentation. Considering the operating conditions of simple power circuits, it will be demonstrated that an incorrect choice of the voltages referential may result in erroneous quantification of some power quality indices, especially in three-phase four wire circuits. The use of a virtual reference point and the neutral conductor as reference have been considered and the simulation results confirm the influence of the voltage reference selection in the evaluation of total harmonic distortion, unbalance factors and voltage sags. Finally a way of linking both methods will be discussed by means of Blakesleypsilas theorem. © Copyright 2010 IEEE - All Rights Reserved.

Natureza e implicações da "heterogeneidade estrutural" da América Latina

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Contexto geológico e estrutural do Maciço Rio Apa, sul do Cráton amazônico - MS

Rio Apa Massif crops out in the Mato Grosso do Sul state and corresponds to the southeastern portion of the Amazonian Craton dominantly Paleoproterozoic in age. Rio Apa Complex is oldest and it is composed mainly by migmatitic orthogneisses, beyond amphybolites, tonalities and granodiorite. Alto Tererê Group is composed by schists, biotitemuscovite gneisses and micaceous quartzites generally rich in garnets, beyond metabasic rocks of low amphibolite facies. The Amoguijá Group is constituted by Alumiador Intrusive Suite, which is represented by a sieno to monzogranitic batholith and Serra da Bocaina Volcanic Suite composed of volcanoclastic rocks of alkali riolites to monzoriolites compositions and pyroclastic products. Overlaying towards East and South occurs Neoproterozoic metasedimentary rocks from the Paraguai Folded Belt (Cuiabá, Corumbá and Jacadigo Groups - Urucum Formation). Structural-metamorphic framewok is identified by five deformational phases but the actual tectonic and metamorphic structure shows the superposed tectonic array of the Paraguai Folded Belt. Rocks from Rio Apa Complex, Alto Tererê Group and Amoguijá Group record an older structural evolution defined by (Dn-1 and Dn). The deformational phases (Dn+1 and Dn+2) are visible mainly in rocks of Paraguai Folded Belt beyond the last deformation (Dn+3) that imprints all sequences.

Dependência estrutural da capacidade de rotação plástic em vigas de concreto armado

Summary In this work the structural dependence of plastic rotation capacity in RC beams is evaluated using the Finite Element Method. The objective is to achieve a better understanding of the non-linear behavior of reinforced concrete members and perform extensive parameter studies, using a rational model developed by Bigaj [1] to analyze the phenomenon of plastic rotation capacity in reinforced concrete members. It is assumed that only bending failure is relevant due to sufficient member resistance against shear and torsion. The paper begins with the physical and theoretical background of the phenomenon of plastic hinge development in RC structures. Special emphasis is laid on the issue of structural dependence of deformation capacity of plastic hinges in RC members. Member size dependence and influence of properties of construction materials were emphasized as well. The essential components of the Bigajs model for calculating the plastic rotation capacity are discussed. The behaviour of the plastic hinge is analysed taking into account the strain localisation in the damage zones of the hinge region. The Fictitious Crack Model (FCM) and the Compressive Damage Zone Model (CDZ) are adopted in a Fracture Mechanics approach to model the behaviour of concrete in tension and compression, respectively. The approach is implemented in FEMOOP, a FEM in-house solver under development, and applied to evaluate ductility in 2D beams. The models were generated with GiD, a pre-processor and post-processor developed by CIMNE, and analyzed with the capabilities implemented in FEMOOP. © Universitat Politècnica de Catalunya, Barcelona, España 2010.

Classificação Estrutural e Qualidade da Madeira do Clone GT 1 de Hevea brasiliensis Muell. Arg

Latex is the main product extracted from rubber trees (Hevea brasiliensis). In Brazil, at the end of the production cycle of latex, the wood of rubber tree is traditionally used for energy purposes, but several international studies have reported consolidated practices of adding value to it. The objective of this paper was to evaluate the quality of wood and classify it structurally based on its mechanical properties. Six 20-year-old trees of the clone GT 1 of rubber tree proceeding from Itajobi, State of Sao Paulo, Brazil were sampled. Reduced dimensions specimens in the radial direction of the wood were produced to evaluate the quality by compression parallel to the grain, static bending and Janka hardness tests. Two specimens, one from the lower log (since the ground up to breast height) and one from the higher log (from breast height up to 2.50 m) were produced for structural classification of the wood based on the characteristic strength in compression parallel to the grain (NBR 7190 norm, 1997). The wood was classified as C40 (fc0k ≥ 40 MPa) class. Results revealed that the strength was not statistically different in the radial direction (except for the Janka hardness), though tending to increase from pith to bark.

Mudança estrutural para a igualdade: Uma visão integrada do desenvolvimento. Trigésimo quarto período de sessões da CEPAL. Síntese

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