339 research outputs found

    Pollutant dispersal in an air-water system mathematical modeling numerical aproximation and computational simulations

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    Orientador: João Frederico da Costa Azevedo MeyerTese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação CientificaResumo: Este trabalho estuda um problema evolutivo de difusão-advecção num sistema ar-água tri-dimensional. Apresenta-se um modelo e o correspondente sistema de EDPs que reúne as equações clássicas de Difusão-advecçãojreação em 3D e a equação de Stokes, junto com condições de contorno descritivas da dinâmica do poluente também na interface entre ar e água. Verificam-se existência e unicidade de solução na formulação variacional. São apresentadas discretizações espacial (elementos finitos de segunda ordem com SUPG) e temporal (CrankNicolson). São obtidas estimativas de erro a priori para Galerkin contínuo e GalerkinjCrank-Nicolson. Apresenta-se um programa computacional para simulações de diferentes cenários com resultados numéricos e saída gráfica para visualização de caráter qualitativo. Evidencia-se, assim, o potencial deste trabalho como suporte robusto na avaliação de estratégias de descarte de poluentesAbstract: This work considers a three-dimensional air-water system pollution discharge problem, modelling it with a system of partial differential equations which includes both the diffusionadvection evolutionary and Stoke's equations. Appropriate boundary conditions are considered, including for the air-water interface, and special attention is dedicated to existence and uniqueness results. ln terms of the numerical approximation, space discretization is undertaken with three-dimensional second-order finite elements, and, in time, a Crank-Nicolson scheme is adopted. A priori estimates are given for the continuous Galerkin and for the GalerkinjCrankNicolson approximations. A numerical algorithm is presented and the qualitative visual output is used to emphasize the potential for simulating and discussing pollution discharge strategiesDoutoradoDoutor em Matemática Aplicad

    Auditoria como ferramenta na identificação e mitigação de fraudes em empresas brasileiras

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    Orientadora : Mayla Cristina CostaMonografia (especialização) - Universidade Federal do Paraná, Setor de Ciências Sociais Aplicadas, Curso de Especialização em MBA em Auditoria IntegralInclui referênciasResumo : Nesta pesquisa exploratória o autor estabelece uma relação entre o evento de fraude e o papel realizado pela Auditoria no sentido de sua detecção e mitigação das causas. A partir de elementos e conceitos da literatura acadêmica, busca-se evidenciar a associação direta da função de Auditor no conhecimento e descoberta da fraude nas empresas brasileiras. Alguns aspectos da análise foram obtidos a partir de pesquisas realizadas por entidades conceituadas em nível nacional e internacional que atuam na área de Auditoria e Consultoria. Por fim, a partir das informações compiladas e com apoio dos elementos bibliográficos, verificou-se a importância da Auditoria como ferramenta indispensável no combate a fraude, assegurando a continuidade operacional das empresas do Brasil

    As aposentadorias e pensões e a concentração dos rendimentos domiciliares per capita no Brasil e na sua área rural: 1981 a 2003.

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    This work has as objective to analyze the participation and the contribution of the household income “retirements and pensions†for the inequality of the distribution of the per capita household income in Brazil and Rural Brazil, in the period from 1981 to 2003. For that, it revises the literature about concentration of income and social welfare in the country, and it uses the Gini index components decomposition methodology: revenue of the main work, revenue of other works, retirements and pensions, donations, rent revenues and other revenues (interests, dividends, etc.). It stands out, in the results, the growing participation of the retirements and pensions and in the 1990`s in relation to the previous decade, with larger intensity in rural Brazil, explained by the social and economic policies of the period. The contribution of that portion of household income for the concentration of income is significant to Brazil in 9 of the 18 analyzed years, and to rural Brazil, starting from the decade of 1990.Rural Social Welfare, Retirements and pensions, Concentration of income., Agribusiness, D31, D63.,

    PREVIDÊNCIA SOCIAL E DESIGUALDADE: A PARTICIPAÇÃO DAS APOSENTADORIAS E PENSÕES NA DISTRIBUIÇÃO DA RENDA NO BRASIL - 1981 A 2001

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    Among the problems presented by Brazilian social security, it may be observed that there are distortions in the criteria and requisites of the simple partition system. The present study is an attempt to evaluate retirement and pension contributions to the inequality of the per capita domiciliay income distribution in Brazil, from 1981 to 2001, through the technique of decomposition of Gini's index. The conclusion drawn is that the retirement and pension income contributes, significantly, to the increase of inequality of the income distribution in Brazil.

    Creep-age forming of AA7475 aluminum panels for aircraft lower wing skin application

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    Creep-age forming (CAF) is an interesting process for the airframe industry, as it is able to form or shape panels into smooth, but complex, curvatures. In the CAF process, the ageing cycle of the alloy is used to relax external loads imposed to the part, through creep mechanisms. Those relaxed stresses impose a new curvature to the part. At the end of the process, significant spring back (sometimes about 70%) is observed and the success in achieving the desired form depends on how the spring back can be predicted in order to compensate it by tooling changes. Most of the applications relate to simple (non stiffened) panels. The present work deals with the CAF of aluminum panels for aircraft wing skin application. CAF was performed using vacuum-bagging autoclave technique in small scale complex shape stiffened panels, machined from an AA7475 alloy plate. An analytical reference model from the literature was employed estimate the spring back effect in such panel geometry. This model that deals with simple plates was adapted to stiffened panels using a geometric simplification, resulting in a semi-empirical model. The results demonstrate that CAF is a promising process to form stiffened panels, and the spring back can be roughly estimated through a simple model and few experiments.Empresa Brasileira de Aeronáutica S.A.Universidade Federal de São Paulo (UNIFESP) Departamento de Ciência e TecnologiaUNIFESP, Depto. de Ciência e TecnologiaSciEL

    Pathogen Recognition by the Long Pentraxin PTX3

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    Innate immunity represents the first line of defence against pathogens and plays key roles in activation and orientation of the adaptive immune response. The innate immune system comprises both a cellular and a humoral arm. Components of the humoral arm include soluble pattern recognition molecules (PRMs) that recognise pathogen-associated molecular patterns (PAMPs) and initiate the immune response in coordination with the cellular arm, therefore acting as functional ancestors of antibodies. The long pentraxin PTX3 is a prototypic soluble PRM that is produced at sites of infection and inflammation by both somatic and immune cells. Gene targeting of this evolutionarily conserved protein has revealed a nonredundant role in resistance to selected pathogens. Moreover, PTX3 exerts important functions at the cross-road between innate immunity, inflammation, and female fertility. Here, we review the studies on PTX3, with emphasis on pathogen recognition and cross-talk with other components of the innate immune system

    Interaction of C1q With Pentraxin 3 and IgM Revisited: Mutational Studies With Recombinant C1q Variants

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    Pentraxins and complement defense collagens are soluble recognition proteins that sense pathogens and altered-self elements, and trigger immune responses including complement activation. PTX3 has been shown to interact with the globular recognition domains (gC1q) of the C1q protein of the classical complement pathway, thereby modulating complement activity. The C1q-PTX3 interaction has been characterized previously by site-specific mutagenesis using individual gC1q domains of each of the three C1q chains. The present study is aimed at revisiting this knowledge taking advantage of full-length recombinant C1q. Four mutations targeting exposed amino acid residues in the gC1q domain of each of the C1q chains (LysA200Asp-LysA201Asp, ArgB108Asp-ArgB109Glu, TyrB175Leu, and LysC170Glu) were introduced in recombinant C1q and the interaction properties of the mutants were analyzed using surface plasmon resonance. All C1q mutants retained binding to C1r and C1s proteases and mannose-binding lectin-associated serine proteases, indicating that the mutations did not affect the function of the collagen-like regions of C1q. The effect of these mutations on the interaction of C1q with PTX3 and IgM, and both the PTX3- and IgM-mediated activation of the classical complement pathway were investigated. The LysA200Asp-LysA201Asp and LysC170Glu mutants retained partial interaction with PTX3 and IgM, however they triggered efficient complement activation. In contrast, the ArgB108Asp-ArgB109Glu mutation abolished C1q binding to PTX3 and IgM, and significantly decreased complement activation. The TyrB175Leu mutant exhibited decreased PTX3- and IgM-dependent complement activation. Therefore, we provided evidence that, in the context of the full length C1q protein, a key contribution to the interaction with both PTX3 and IgM is given by the B chain Arg residues that line the side of the gC1q heterotrimer, with a minor participation of a Lys residue located at the apex of gC1q. Furthermore, we generated recombinant forms of the human PTX3 protein bearing either D or A at position 48, a polymorphic site of clinical relevance in a number of infections, and observed that both allelic variants equally recognized C1q

    Incorporation of Pentraxin 3 into Hyaluronan Matrices Is Tightly Regulated and Promotes Matrix Cross-linking

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    Mammalian oocytes are surrounded by a highly hydrated hyaluronan (HA)-rich extracellular matrix with embedded cumulus cells, forming the cumulus cell·oocyte complex (COC) matrix. The correct assembly, stability, and mechanical properties of this matrix, which are crucial for successful ovulation, transport of the COC to the oviduct, and its fertilization, depend on the interaction between HA and specific HA-organizing proteins. Although the proteins inter-α-inhibitor (IαI), pentraxin 3 (PTX3), and TNF-stimulated gene-6 (TSG-6) have been identified as being critical for COC matrix formation, its supramolecular organization and the molecular mechanism of COC matrix stabilization remain unknown. Here we used films of end-grafted HA as a model system to investigate the molecular interactions involved in the formation and stabilization of HA matrices containing TSG-6, IαI, and PTX3. We found that PTX3 binds neither to HA alone nor to HA films containing TSG-6. This long pentraxin also failed to bind to products of the interaction between IαI, TSG-6, and HA, among which are the covalent heavy chain (HC)·HA and HC·TSG-6 complexes, despite the fact that both IαI and TSG-6 are ligands of PTX3. Interestingly, prior encounter with IαI was required for effective incorporation of PTX3 into TSG-6-loaded HA films. Moreover, we demonstrated that this ternary protein mixture made of IαI, PTX3, and TSG-6 is sufficient to promote formation of a stable (i.e. cross-linked) yet highly hydrated HA matrix. We propose that this mechanism is essential for correct assembly of the COC matrix and may also have general implications in other inflammatory processes that are associated with HA cross-linking

    Estacas de amoreira tratadas com hormônios vegetais em dois sistemas de plantio e referentes coberturas do estufim

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    Four experiments on root formation on cuttings of mulberry trees of the variety Catania 1 were carried out. In each case the hormones Dieradix "M D", Dieradix "D", indol 3-yl-acetic acid, and I-naphthyl acetic acid were used, besides the control, without hormone. In all cases "normal" and "upside-down" planting were tried. The percentage x of cuttings with roots, after 54 days, were computed and transformed by the formula y = arc sin √P/100 for use in statistical analysis. The combined analysis of variance of the 4 trials led to the following results: "Upside-down" planting showed significantly higher percentage of rooting; Indol 3-yl-acetic acid was significantly better than control or other hormones. The percentages of rooted cuttings were as follows: Normal planting Upside-dow planting Indol 3-yl acetic acid 43.5% 90.9% I-naphthyl acetic acid 1.9% 69.3% Control 4.7% 22.2% Dieradix «M D» 2.4% 63.8% Dieradix «D» 1.3% 36.0
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