969 resultados para BASE-LINE CREATININE


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Three new trinuclear heterometallic nickel(II)manganese(II) complexes, [(NiL)2Mn(NCS)2] (1), [(NiL)2Mn(NCO)2] (2), and [{NiL(EtOH)}2Mn(NO2)2]center dot 2EtOH (3), have been synthesized by using [NiL] as the so-called ligand complex [where H2L = N,N'-bis(salicylidene)-1,3-propanediamine] and have been structurally characterized. Crystal structure analyses revealed that complexes 1 and 2 are angular trinuclear species, in which two terminal four-coordinate square planar [NiL] moieties are coordinated to a central MnII through double phenoxido bridges. The MnII is in a six-coordinate distorted octahedral environment that is bonded additionally to two mutually cis nitrogen atoms of terminal thiocyanate (in 1) and cyanate (in 2). In complex 3, in addition to the double phenoxo bridge, the two terminal NiII ions are linked to the central MnII by means of a nitrite bridge (1?N:2?O) that, together with a coordinated ethanol molecule, gives rise to an octahedral environment around the NiII ions and consequently the structure becomes linear. Catecholase activity of these three complexes was examined by using 3,5-di-tert-butylcatechol (3,5-DTBC) as the substrate. All three complexes mimic catecholase activity and the rate of catechol oxidation follows saturation kinetics with respect to the substrate and first-order kinetics with respect to the catalyst. The EPR spectra of the complexes exhibit characteristic six line spectra, which indicate the presence of high-spin octahedral MnII species in solution state. The ESI-MS positive spectrum of 1 in the presence of 3,5-DTBC has been recorded to investigate possible complexsubstrate intermediates.

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This paper presents an image motion model for airborne three-line-array (TLA) push-broom cameras. Both aircraft velocity and attitude instability are taken into account in modeling image motion. Effects of aircraft pitch, roll, and yaw on image motion are analyzed based on geometric relations in designated coordinate systems. The image motion is mathematically modeled by image motion velocity multiplied by exposure time. Quantitative analysis to image motion velocity is then conducted in simulation experiments. The results have shown that image motion caused by aircraft velocity is space invariant while image motion caused by aircraft attitude instability is more complicated. Pitch,roll and yaw all contribute to image motion to different extents. Pitch dominates the along-track image motion and both roll and yaw greatly contribute to the cross-track image motion. These results provide a valuable base for image motion compensation to ensure high accuracy imagery in aerial photogrammetry.

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The study of Wolf-Rayet stars plays an important role in evolutionary theories of massive stars. Among these objects, similar to 20 per cent are known to be in binary systems and can therefore be used for the mass determination of these stars. Most of these systems are not spatially resolved and spectral lines can be used to constrain the orbital parameters. However, part of the emission may originate in the interaction zone between the stellar winds, modifying the line profiles and thus challenging us to use different models to interpret them. In this work, we analysed the He II lambda 4686 angstrom + C IV lambda 4658 angstrom blended lines of WR 30a (WO4+O5) assuming that part of the emission originate in the wind-wind interaction zone. In fact, this line presents a quiescent base profile, attributed to the WO wind, and a superposed excess, which varies with the orbital phase along the 4.6-d period. Under these assumptions, we were able to fit the excess spectral line profile and central velocity for all phases, except for the longest wavelengths, where a spectral line with constant velocity seems to be present. The fit parameters provide the eccentricity and inclination of the binary orbit, from which it is possible to constrain the stellar masses.

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Meningioma tumor growth involves the subarachnoid space that contains the cerebrospinal fluid. Modeling tumor growth in this microenvironment has been associated with widespread leptomeningeal dissemination, which is uncharacteristic of human meningiomas. Consequently, survival times and tumor properties are varied, limiting their utility in testing experimental therapies. We report the development and characterization of a reproducible orthotopic skull-base meningioma model in athymic mice using the IOMM-Lee cell line. Localized tumor growth was obtained by using optimal cell densities and matrigel as the implantation medium. Survival times were within a narrow range of 17-21 days. The xenografts grew locally compressing surrounding brain tissue. These tumors had histopathologic characteristics of anaplastic meningiomas including high cellularity, nuclear pleomorphism, cellular pattern loss, necrosis and conspicuous mitosis. Similar to human meningiomas, considerable invasion of the dura and skull and some invasion of adjacent brain along perivascular tracts were observed. The pattern of hypoxia was also similar to human malignant meningiomas. We use bioluminescent imaging to non-invasively monitor the growth of the xenografts and determine the survival benefit from temozolomide treatment. Thus, we describe a malignant meningioma model system that will be useful for investigating the biology of meningiomas and for preclinical assessment of therapeutic agents.

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The interactions of emeraldine base form of polyaniline (EB-PANI) and Eu(III) ions in 1-methyl-2-pyrrolidinone (NMP) solution and in films have been investigated by UV-vis-NIR, resonance Raman. luminescence and electron paramagnetic resonance (EPR) spectroscopies. These spectroscopic techniques allowed to characterize quinone and semiquinone segments in the polymeric chains. and the oxidation state of europium ions in Eu-PANI samples. For high values of Eu(III)/N molar ratio (24/1) the presence of a weak polaronic absorption band at 980 nm in UV-vis-NIR spectrum and the observation of bands at 1330 and 1378 (nu(center dot)(C-N+)) cm(-1) due to emeraldine salt in the Raman spectrum at 1064 nm indicate a low doping degree. Oxidation of EB-PANI to pernigraniline base (PB-PANI) occurs in diluted solutions. The experimental data showed that the solvent plays an important role on the nature of formed species. The narrow EPR signal at g = 2.006 (line width 8G) confirms the presence of PANI radical cations in Eu-PANI film. The absence of broad signal characteristic of Eu(II) in EPR spectrum suggested that europium ions are primarily at Eu(III) oxidation state. The luminescence spectra of Eu-PANI film presented emission bands at 405 and 418 nm assigned to PANI moieties and bands at 594,615 and 701 nm assigned to (5)D(0) -> (7)F(J) (J = 1, 2 and 4, respectively) transitions of Eu(III). EPR and photoluminescence data confirm that europium ions are mainly in Eu(III) oxidation state in Eu(III)/PANI films. (C) 2008 Elsevier B.V. All rights reserved.

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Uma das questões críticas relacionadas com um Ambiente Adaptativo de Ensino e Aprendizagem baseado na Web diz respeito à eficácia da aprendizagem do aluno remoto. Assim como diversos trabalhos de pesquisa na literatura, nosso estudo preocupou-se com a modelagem do Estilo Cognitivo de Aprendizagem (ECA) do aluno visando, em um futuro próximo, a adaptação dos conteúdos pedagógicos a esta importante característica individual do aluno. Esta tese descreve a metodologia utilizada para investigar como modelar o ECA do aluno remoto, baseado na observação e análise de seu comportamento em um ambiente de ensino e aprendizagem na Web. Em nosso estudo, o ECA representa o estágio de desenvolvimento cognitivo do aluno, de acordo com a taxonomia de Bloom. Nós acreditamos que os principais benefícios de adaptar a instrução ao ECA do aluno estão relacionados com a possibilidade de oportunizar a ampliação de suas habilidades cognitivas, assim como oportunizar a aprendizagem em profundidade sobre os conteúdos em estudo. A metodologia quase-experimental usada para a modelagem do ECA do aluno compreendeu duas fases distintas: (i) geração das classes de ECA a partir da aplicação de um teste psicológico em uma amostra da população-alvo; e (ii) desenvolvimento do módulo de ensino experimental e o estudo das Trajetórias de Aprendizagem (TA) padrão das classes de ECA, a partir da observação de seus comportamentos durante a execução de uma sessão de estudo na Web. Como resultado deste estudo, identificamos os principais indicadores, que melhor discriminaram as classes de ECA consideradas. Os resultados foram obtidos a partir da observação e análise das TAs na Web. Todo o conhecimento obtido a partir desta investigação deverá nos permitir automatizar o diagnóstico do ECA do aluno remoto. Este conhecimento também será utilizado como base para o desenvolvimento dos conteúdos a serem oferecidos ao aluno pelo Ambiente Adaptativo de Ensino e Aprendizagem baseado na Web.

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A Porto Santo Line é a empresa responsável pela ligação marítima entre as ilhas Madeira e Porto Santo, oferecendo, para além do transporte, um conjunto de serviços e produtos que estão associado à sua actividade principal. A sua base de clientes inclui não só os residentes de ambas as ilhas, mas também muitos dos turistas que visitam o arquipélago. O posicionamento desta empresa no mercado é feito das formas tradicionais, onde se inclui uma rede de balcões e um site através do qual os clientes podem aceder aos produtos e serviços que constitui a oferta da Porto Santo Line. Num esforço de reforçar a sua presença no mercado e de intensificar a sua aposta na inovação, a empresa tem procurado encontrar novas formas e novos canais para chegar aos seus clientes. Este projecto visa dotar a Porto Santo Line de uma aplicação que estenda a sua presença no mercado, oferecendo aos seus clientes a possibilidade de aceder aos seus produtos e serviços através de equipamentos móveis. Este relatório documenta a realização deste projecto, dando principal enfase ao processo adoptado, assim como ao desenho do sistema e sua avaliação. Procurou-se igualmente evidenciar ao longo do relatório, as considerações mais relevantes na elaboração de um projecto com estas características.

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

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Foram conduzidos dois experimentos com o objetivo de avaliar a utilização de duas fontes de metionina (em pó ou líquida) em rações formuladas com base em aminoácidos digestíveis ou totais para frangas de reposição leves e semipesadas, nas fases inicial (de 1 a 6 semanas de idade) e de crescimento (de 11 a 16 semanas de idade). em cada experimento, foram utilizadas 384 aves distribuídas em delineamento inteiramente ao acaso, em esquema fatorial 2 × 2 × 2, composto de duas linhagens (Hy-Line W36 e Hy-Line Brown), duas fontes de metionina (HMTBA - 88% e DL-Metionina - 99%) e dois critérios de formulação da dieta (aminoácidos totais e digestíveis), totalizando oito tratamentos, cada um com seis repetições de oito aves. Foram avaliados os consumos de ração, proteína bruta e energia metabolizável, o peso e ganho de peso corporal e a conversão alimentar das aves. Não houve interação entre os fatores para nenhuma das variáveis estudadas. As aves da linhagem Brown apresentaram maior consumo de ração, peso corporal e ganho de peso. As fontes de metionina e os critérios de formulação de ração não influenciaram as características de desempenho. As aves das linhagens W36 e Brown da linhagem Hy-Line apresentam diferentes perfis de desenvolvimento corporal. A metionina em pó (DL-metionina - 99%) ou a líquida (HMTBA - 88%), assim como os critérios de formulação de ração (aminoácidos totais ou digestíveis) proporcionam desempenho semelhante em aves de reposição.

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Most algorithms for state estimation based on the classical model are just adequate for use in transmission networks. Few algorithms were developed specifically for distribution systems, probably because of the little amount of data available in real time. Most overhead feeders possess just current and voltage measurements at the middle voltage bus-bar at the substation. In this way, classical algorithms are of difficult implementation, even considering off-line acquired data as pseudo-measurements. However, the necessity of automating the operation of distribution networks, mainly in regard to the selectivity of protection systems, as well to implement possibilities of load transfer maneuvers, is changing the network planning policy. In this way, some equipments incorporating telemetry and command modules have been installed in order to improve operational features, and so increasing the amount of measurement data available in real-time in the System Operation Center (SOC). This encourages the development of a state estimator model, involving real-time information and pseudo-measurements of loads, that are built from typical power factors and utilization factors (demand factors) of distribution transformers. This work reports about the development of a new state estimation method, specific for radial distribution systems. The main algorithm of the method is based on the power summation load flow. The estimation is carried out piecewise, section by section of the feeder, going from the substation to the terminal nodes. For each section, a measurement model is built, resulting in a nonlinear overdetermined equations set, whose solution is achieved by the Gaussian normal equation. The estimated variables of a section are used as pseudo-measurements for the next section. In general, a measurement set for a generic section consists of pseudo-measurements of power flows and nodal voltages obtained from the previous section or measurements in real-time, if they exist -, besides pseudomeasurements of injected powers for the power summations, whose functions are the load flow equations, assuming that the network can be represented by its single-phase equivalent. The great advantage of the algorithm is its simplicity and low computational effort. Moreover, the algorithm is very efficient, in regard to the accuracy of the estimated values. Besides the power summation state estimator, this work shows how other algorithms could be adapted to provide state estimation of middle voltage substations and networks, namely Schweppes method and an algorithm based on current proportionality, that is usually adopted for network planning tasks. Both estimators were implemented not only as alternatives for the proposed method, but also looking for getting results that give support for its validation. Once in most cases no power measurement is performed at beginning of the feeder and this is required for implementing the power summation estimations method, a new algorithm for estimating the network variables at the middle voltage bus-bar was also developed

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

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Purpose: This study compared the effect of two postpolymerization heat treatments on the cytotoxicity of three denture base resins on L929 cells using 3H-thymidine incorporation and MTT assays. Materials and Methods: Sample disks of Lucitone 550, QC 20, and Acron MC resins were fabricated under aseptic conditions and stored in distilled water at 37°C for 48 hours. Specimens were then divided into three groups: (1) heat treated in microwave oven for 3 minutes at 500 W; (2) heat treated in water bath at 55°C for 60 minutes; and (3) no heat treatment. Eluates were prepared by placing three disks into a sterile glass vial with 9 mL of Eagle's medium and incubating at 37°C for 24 hours. The cytotoxic effect from the eluates was evaluated using the 3H-thymidine incorporation and MTT assays, which reflect DNA synthesis levels and cell metabolism, respectively. Results: The components leached from the resins were cytotoxic to L929 cells when 3H- thymidine incorporation assay was employed. In contrast, eluates from all resins revealed noncytotoxic effects as measured by MTT assay. For both MTT assay and 3H-thymidine incorporation, the heat treatments did not decrease the cytotoxicity of the materials tested. Conclusion: Resins were graded by 3H-thymidine incorporation assay as slightly cytotoxic and by MTT assay as noncytotoxic. Cytotoxicity of the denture base materials was not influenced by microwave or water bath heat treatment.

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Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Ciência da Informação - FFC