425 research outputs found

    Crystallographic texture evolution in Ti–35Nb alloy deformed by cold rolling

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    This work presents the results of a microstructural characterization of the Ti–35Nb alloy deformed by cold rolling. Initially, samples of the Ti–35Nb (wt%) alloy were obtained by electric arc melting. After melting, these samples were solution heat-treated at 1000 °C for 8 h and water quenched. The resulting microstructure was composed of β-phase (bcc) combined with orthorhombic martensite (α″). Samples were cold-rolled in multiple passes to reduce their thickness by up to 85% without intermediary annealing. They were then characterized by light optical microscopy, X-ray diffraction and Vickers hardness measurements. Young’s modulus was determined by ultrasonic methods and nanoindentation measurements. The texture evolution and orientation relationship between phases were studied by X-ray diffraction and electron backscatter diffraction (EBSD). The results reveal the presence of shear bands in the deformed samples, an orientation of the orthorhombic martensite phase in relation to the rolling direction, and variations of Young’s modulus in response to deformation. The textural results of the β-phase show a typical bcc rolling texture with strong (1 1 0) fiber and weak (1 1 1) fiber. The intensity of the (1 1 0) fiber increases with deformation60653660CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPNão temNão temNão temThe authors gratefully acknowledge the Brazilian research funding agencies FAPESP (State of São Paulo Research Foundation), CNPq (National Council for Scientific and Technological Development) and CAPES (Federal Agency for the support and Evaluation of Graduate Education) for their financial support of this wor

    On the finiteness of noncommutative supersymmetric QED/sub 3/ in the covariant superfield formulation

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    The three-dimensional noncommutative supersymmetric QED is investigated within the superfield approach. We prove the absence of UV/IR mixing in the theory at any loop order and demonstrate its one-loop finiteness

    The low energy limit of the non-commutative Wess-Zumino model

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    The non-commutative Wess-Zumino model is used as a prototype for studying the low energy behaviour of a renormalizable non-commutative field theory. We start by deriving the potential mediating the fermion-fermion and boson-boson interactions in the non-relativistic regime. The quantum counterparts of these potentials are afflicted by irdering ambiguities but we show that there exists an ordering prescription which makes them hermitean. For space/space noncommutativity it turns out that Majorana fermions may be pictured as rods oriented perpendicularly to the direction of motion showing a lack of localituy, while bosons remain insensitive to the effects of noncommutativity. For time/space noncommutativity bosopns and fermions can be regarded as rods oriented along the direction of motion. For both cases of noncommutativity the scattering state described scattered waves, with at least one wave having negative time delay signalizing the underlying nonlocality. The superfield formulation of the model is used to compute the corresponding effective action in the one- and two-loop approximations. In the case of time/space noncommutativity, unitarity is violated in the relativistic regime. However, this does not preclude the existence of the unitary low energy limit.Comment: 14 pages, 2 figures, minor correction

    The Brazilian Registry of Adult Patient Undergoing Cardiovascular Surgery, the BYPASS Project: Results of the First 1,722 Patients

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    Objective: To report the early results of the BYPASS project - the Brazilian registrY of adult Patient undergoing cArdiovaScular Surgery - a national, observational, prospective, and longitudinal follow-up registry, aiming to chart a profile of patients undergoing cardiovascular surgery in Brazil, assessing the data harvested from the initial 1,722 patients. Methods: Data collection involved institutions throughout the whole country, comprising 17 centers in 4 regions: Southeast (8), Northeast (5), South (3), and Center-West (1). The study population consists of patients over 18 years of age, and the types of operations recorded were: coronary artery bypass graft (CABG), mitral valve, aortic valve (either conventional or transcatheter), surgical correction of atrial fibrillation, cardiac transplantation, mechanical circulatory support and congenital heart diseases in adults. Results: 83.1% of patients came from the public health system (SUS), 9.6% from the supplemental (private insurance) healthcare systemsand 7.3% from private (out-of-pocket) clinic. Male patients comprised 66%, 30% were diabetics, 46% had dyslipidemia, 28% previously sustained a myocardial infarction, and 9.4% underwent prior cardiovascular surgery. Patients underwent coronary artery bypass surgery were 54.1% and 31.5% to valve surgery, either isolated or combined. The overall postoperative mortality up to the 7th postoperative day was 4%for CABG was 2.6%, and for valve operations, 4.4%. Conclusion: This first report outlines the consecution of the Brazilian surgical cardiac database, intended to serve primarily as a tool for providing information for clinical improvement and patient safety and constitute a basis for production of research protocols.Univ Fed Sao Paulo UNIFESP EPM, Hosp Sao Paulo, Sao Paulo, SP, BrazilHosp Caridade Sao Vicente Paulo, Jundiai, SP, BrazilInst Med Integral Prof Fernando Figueira IMIP, Recife, PE, BrazilHosp Base FUNFARME & FAMERP, Sao Jose Do Rio Preto, SP, BrazilIMC, Sao Jose Do Rio Preto, SP, BrazilIrmandade Santa Casa Sao Paulo INCT HPV, Fac Ciencias Med Santa Casa Sao Paulo, Sao Paulo, SP, BrazilFundacao Univ Cardiol, Inst Cardiol Rio Grande do Sul, Porto Alegre, RS, BrazilInst Coracao Natal, Natal, RN, BrazilInst Cardiol Dist Fed, Brasilia, DF, BrazilUniv Fed Maranhao HU UFMA, Univ Hosp, Sao Luis, MA, BrazilHosp Evangelico, Cachoeiro De Itapemirim, ES, BrazilHosp Coracao Sergipe, Aracaju, SE, BrazilHosp Nossa Senhora Salete, Inst Cirurgia Cardiovasc ICCV, Cascavel, PR, BrazilHosp Wilson Rosado, Mossoro, RN, BrazilHosp Bosque Saude, Sao Paulo, SP, BrazilHosp Univ Santa Maria, Santa Maria, RS, BrazilHosp Coracao HCor, Sao Paulo, SP, BrazilHosp Coracao IP HCor, Ins Pesquisa, Sao Paulo, SP, BrazilInst Coracao InCor, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP EPM, Hosp Sao Paulo, Sao Paulo, SP, BrazilWeb of Scienc

    Repertoire, Genealogy and Genomic Organization of Cruzipain and Homologous Genes in Trypanosoma cruzi, T. cruzi-Like and Other Trypanosome Species

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    Trypanosoma cruzi, the agent of Chagas disease, is a complex of genetically diverse isolates highly phylogenetically related to T. cruzi-like species, Trypanosoma cruzi marinkellei and Trypanosoma dionisii, all sharing morphology of blood and culture forms and development within cells. However, they differ in hosts, vectors and pathogenicity: T. cruzi is a human pathogen infective to virtually all mammals whilst the other two species are non-pathogenic and bat restricted. Previous studies suggest that variations in expression levels and genetic diversity of cruzipain, the major isoform of cathepsin L-like (CATL) enzymes of T. cruzi, correlate with levels of cellular invasion, differentiation, virulence and pathogenicity of distinct strains. In this study, we compared 80 sequences of genes encoding cruzipain from 25 T. cruzi isolates representative of all discrete typing units (DTUs TcI-TcVI) and the new genotype Tcbat and 10 sequences of homologous genes from other species. The catalytic domain repertoires diverged according to DTUs and trypanosome species. Relatively homogeneous sequences are found within and among isolates of the same DTU except TcV and TcVI, which displayed sequences unique or identical to those of TcII and TcIII, supporting their origin from the hybridization between these two DTUs. In network genealogies, sequences from T. cruzi clustered tightly together and closer to T. c. marinkellei than to T. dionisii and largely differed from homologues of T. rangeli and T. b. brucei. Here, analysis of isolates representative of the overall biological and genetic diversity of T. cruzi and closest T. cruzi-like species evidenced DTU- and species-specific polymorphisms corroborating phylogenetic relationships inferred with other genes. Comparison of both phylogenetically close and distant trypanosomes is valuable to understand host-parasite interactions, virulence and pathogenicity. Our findings corroborate cruzipain as valuable target for drugs, vaccine, diagnostic and genotyping approaches
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