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au:BRAGA, JOAO P.
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1.
Green Synthesis, Characterization and Antibacterial and Leishmanicidal Activities of Silver Nanoparticles Obtained from Aqueous Extract of Eucalyptus grandis
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Oliveira, Lucas M. F.
; Silva, Ueveton P. da
; Braga, João Pedro V.
; Teixeira, Álvaro V. N. C.
; Ribon, Andréa O. B.
; Varejão, Eduardo V. V.
; Coelho, Eduardo A. F.
; Freitas, Camila S. de
; Teixeira, Róbson R.
; Moreira, Renata P L.
.
This work describes a green synthesis, the characterization, and biological evaluation of silver nanoparticles (AgNPs). The AgNPs suspension was synthesized using aqueous leaf extract of Eucalyptus grandis, which presented a characteristic band at 407 nm in the UV-Vis spectrum. The AgNPs presented a spherical shape and size of 9.7 ± 0.3 nm. The nanoparticles were stable over a month, indicating that E. grandis’ extract is suitable for their preparation and stabilization. The X-ray analysis showed that the crystallinity of AgNPs corresponded to the centered face phase of silver. The antibacterial and leishmanicidal activities of AgNPs were evaluated. The AgNPs presented antibacterial activity on the Gram-negative bacteria Escherichia coli at 53.9 µg mL-1. The leishmanicidal activity evaluation against promastigote forms of Leishmania infantum, Leishmania amazonensis, and Leishmania braziliensis showed that the biological response is dependent on the volume of AgNP suspension. It was demonstrated that L. infantum was more sensitive to the nanoparticle’s treatment than L. amazonensis and L. braziliensis. The treatment of L infantum promastigotes with 150 µL of AgNP suspension reduced parasite growth by 67.9%, a result which was similar to the treatment with 1 (66.7%) or 2 µL (70.6%) of amphotericin B used as a positive control.
2.
“Pseudo-Geyser Sign” as the First Presentation of Septic Arthritis of the Shoulder
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Abstract Massive rotator cuff tears can lead to large cysts, extending from the subacromial space through the acromioclavicular joint into a subcutaneous cyst, with a typical “geyser sign” on magnetic resonance imaging (MRI). To our knowledge, no cases of transdeltoid pseudo-cyst as first manifestation of septic arthritis have ever been reported. A 79-year-old female presented to the Emergency Department (ED) with a two-day evolution of a painful tumefaction over her right shoulder. She had been admitted to the ED 16 days before, after being bitten by a dog. Tumefaction drainage revealed a total cell count of 50320 cells/mL. MRI revealed glenohumeral joint cavity’s fluid “decompression” through the deltoid. Septic arthritis was presumed as the cause of the pseudo-cyst, configuring a “pseudo-geyser sign” on MRI. Septic arthritis is an orthopedic emergency, whose early diagnosis, ED referral and treatment are crucial.
Resumo Ruturas maciças da coifa dos rotadores podem levar à formação de grandes quistos, que se estendem do espaço subacromial, através da articulação acromioclavicular, formando um quisto subcutâneo, com um “geyser sign” típico na ressonância magnética (RM). Até onde sabemos, nenhum caso de pseudo-quisto transdeltoide como primeira manifestação de artrite séptica foi relatado. Uma mulher de 79 anos recorreu ao Serviço de Urgência (SU) com uma tumefação dolorosa no ombro direito com dois dias de evolução. Ela tinha recorrido ao SU 16 dias antes, após ter sido mordida por um cão. A drenagem de tumefação revelou uma contagem total de células de 50320 células/mL. A RM revelou “descompressão” do fluido da cavidade articular glenoumeral através do deltoide. A artrite sética foi presumida como a causa do pseudoquisto, configurando um “pseudo-geyser sign” na RM. A artrite sética é uma emergência ortopédica, cujo diagnóstico precoce, encaminhamento ao SU e tratamento são cruciais.
3.
Ablação Septal com Cateteres e Radiofrequência Guiada pela Ecocardiografia para Tratamento de Pacientes com Cardiomiopatia Hipertrófica Obstrutiva: Experiência Inicial
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Valdigem, Bruno P.
; Correia, Edileide B.
; Moreira, Dalmo A. R.
; Bihan, David Le
; Pinto, Ibraim Masciarelli Francisco
; Abizaid, Alexandre A. Cunha
; Andalaft, Rogério Braga
; Paladino Filho, Antonio Tito
; Silva, Halstead Alarcão Gomes Pereira da
; Viesi, Joao Henrique Zucco
.
Resumo Fundamentos A cardiomiopatia hipertrófica (CMH) pode causar obstrução da via de saída do ventrículo esquerdo (VSVE) e ser responsável pelo surgimento de sintomas limitantes, como cansaço físico. Quando tais sintomas são refratários ao tratamento farmacológico, os tratamentos alternativos intervencionistas podem ser úteis, como a ablação septal por meio da infusão de álcool na artéria coronária ou por meio da miectomia cirúrgica. Recentemente, o uso de cateter de radiofrequência (RF) para ablação do septo endocárdico guiado por mapeamento eletroanatômico mostrou-se eficaz apesar da elevada incidência de bloqueio atrioventricular total. Uma alternativa seria a aplicação de radiofrequência no ponto de início do gradiente septal guiada pelo ecocardiograma transesofágico (ETE). O ecocardiograma é um método de imagem com elevada acurácia para determinação da anatomia septal. Objetivo Avaliar o efeito em longo prazo da ablação septal para alívio do gradiente ventrículo-arterial, utilizando o ETE para auxiliar no posicionamento do cateter na área de maior obstrução septal. Avaliar também os efeitos da ablação na classe funcional e parâmetros ecocardiográficos. Métodos Doze pacientes sintomáticos com obstrução da VSVE, refratários à terapia farmacológica, foram submetidos à ablação endocárdica septal com cateteres com ponta de 8 mm, cujo posicionamento foi orientado na região de maior obstrução com auxílio do ETE. Foram realizadas aplicações de radiofrequência (RF) termocontrolada e escalonadas sobre a área alvo. Após cada aplicação, o gradiente era reavaliado e nova aplicação era realizada de acordo com critério clínico. Foram avaliados os efeitos das aplicações de RF tanto para o gradiente em repouso como para o provocado por meio da manobra de Valsalva, e considerado o gradiente. As diferenças foram significativas quando o valor de p foi menor ou igual a 0,05. Resultados Observou-se que a redução da média dos gradientes máximos obtidos foi de 96,8±34,7 mmHg para 62,7±25,4 mmHg ao final de três meses do procedimento (p=0,0036). Após um ano, a média dos gradientes máximos obtidos foi de 36,1±23,8 mmHg (p=0,0001). O procedimento foi bem tolerado e não houve registro de bloqueio atrioventricular total e nem complicações graves. Conclusão A ablação septal guiada pelo ETE foi eficaz e segura, com resultados mantidos durante o período de seguimento clínico. É uma opção razoável para o tratamento intervencionista da obstrução da VSVE em CMH.
Abstract Background Hypertrophic cardiomyopathy (HCM) can cause obstruction in the left ventricular outflow tract (LVOT), and be responsible for the onset of limiting symptoms, such as tiredness. When such symptoms are refractory to pharmacological treatment, interventionist alternative therapies can be useful, such as septal ablation through the infusion of alcohol in the coronary artery or through myectomy. Recently, the use of a radiofrequency (RF) catheter for endocardial septal ablation guided by electroanatomic mapping has proven to be efficient, despite the high incidence of complete atrioventricular block. An alternative would be the application of RF at the beginning point of the septal gradient guided by the transesophageal echocardiography (TEE). The echocardiography is an imaging method with high accuracy to determine septal anatomy. Objective To assess the long term effect of septal ablation for the relief of ventricular-arterial gradient, using TEE to help place the catheter in the area of larger septal obstruction. Besides, to assess the effects of ablation on the functional class and echocardiographic parameters. Methods Twelve asymptomatic patients, with LVOT obstruction, refractory to pharmacological therapy, underwent endocardial septal ablation with 8mm-tip catheters, whose placement was oriented in the region of larger obstruction, assisted by the TEE. Temperature-controlled and staggered RF applications were performed. After each application, the gradient was reassessed and a new application was performed according to the clinical criterion. The effects of RF applications were assessed both for the gradient at rest and for that provoked by the Valsalva maneuver, and considering the gradient. The differences were significant when p-value was lower than or equal to 0.05. Results It was possible to observe that the mean reduction of the maximum gradients was from 96.8±34.7 mmHg to 62.7±25.4 mmHg three months after the procedure (p=0.0036). After one year, the mean of maximum gradient was 36.1±23.8 mmHg (p=0.0001). The procedure was well tolerated, without records of complete atrioventricular block nor severe complications. Conclusion The TEE-guided septal ablation was efficient and safe, and the results were maintained during the clinical follow-up period. It is a reasonable option for the interventionist treatment of LVOT obstruction in HCM.
4.
COVID-19 in the Perioperative Period of Cardiovascular Surgery: the Brazilian Experience
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Gomes, Walter J.
; Rocco, Isadora
; Pimentel, Wallace S.
; Pinheiro, Aislan H. B.
; Souza, Paulo M. S.
; Costa, Luiz A. A.
; Teixeira, Marjory M. P.
; Ohashi, Leonardo P.
; Bublitz, Caroline
; Begot, Isis
; Moreira, Rita Simone L
; Hossne Jr, Nelson A.
; Vargas, Guilherme F.
; Branco, João Nelson R.
; Teles, Carlos A.
; Medeiros, Eduardo A. S.
; Sáfadi, Camila
; Rampinelli, Amândio
; Moratelli Neto, Leopoldo
; Rosado, Anderson Rosa
; Mesacasa, Franciele Kuhn
; Capriata, Ismael Escobar
; Segalote, Rodrigo Coelho
; Palmieri, Deborah Louize da Rocha Vianna
; Jardim, Amanda Cristina Mendes
; Vianna, Diego Sarty
; Coutinho, Joaquim Henrique de Souza Aguiar
; Jazbik, João Carlos
; Coutinho, Henrique Madureira da Rocha
; Kikuta, Gustavo
; Almeida, Zely Sant'Anna Marotti de
; Feguri, Gibran Roder
; Lima, Paulo Ruiz Lucio de
; Franco, Anna Carolina
; Borges, Danilo de Cerqueira
; Cruz, Felipe Ramos Honorato De La
; Croti, Ulisses Alexandre
; Borim, Bruna Cury
; Marchi, Carlos Henrique De
; Goraieb, Lilian
; Postigo, Karolyne Barroca Sanches
; Jucá, Fabiano Gonçalves
; Oliveira, Fátima Rosane de Almeida
; Souza, Rafael Bezerra de
; Zilli, Alexandre Cabral
; Mas, Raul Gaston Sanchez
; Bettiati Junior, Luiz Carlos
; Tranchesi, Ricardo
; Bertini Jr, Ayrton
; Franco, Leandro Vieira
; Fernandes, Priscila
; Oliveira, Fabiana
; Moraes Jr, Roberto
; Araújo, Thiago Cavalcanti Vila Nova de
; Braga, Otávio Penna
; Pedrosa Sobrinho, Antônio Cavalcanti
; Teixeira, Roberta Tavares Barreto
; Camboim, Irla Lavor Lucena
; Gomes, Eduardo Nascimento
; Reis, Pedro Horigushi
; Garcia, Luara Piovan
; Scorsioni, Nelson Henrique Goes
; Lago, Roberto
; Guizilini, Solange
.
Brazilian Journal of Cardiovascular Surgery
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Abstract Introduction: We investigated the clinical course and outcomes of patients submitted to cardiovascular surgery in Brazil and who had developed symptoms/signs of coronavirus disease 2019 (COVID-19) in the perioperative period. Methods: A retrospective multicenter study including 104 patients who were allocated in three groups according to time of positive real time reverse transcriptase-polymerase chain reaction (RT-PCR) for the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2): group 1, patients who underwent cardiac surgery > 10 days after positive RT-PCR; group 2, patients with a positive RT-PCR within 10 days before or after surgery; group 3, patients who presented positive RT-PCR > 10 days after surgery. The primary outcome was mortality and secondary outcomes were postoperative complications, intensive care unit (ICU) length of stay, and postoperative days of hospitalization. Results: The three groups were similar with respect to age, the European System of Cardiac Operative Risk Evaluation score, and comorbidities, except hypertension. Postoperative complications and death were significantly higher in groups 2 and 3 than in group 1, and no significant difference between groups 2 and 3 was seen. Group 2 showed a high prevalence of surgery performed as an urgent procedure. Although no significant differences were observed in ICU length of stay, total postoperative hospitalization time was significantly higher in group 3 than in groups 1 and 2. Conclusion: COVID-19 affecting the postoperative period of patients who underwent cardiovascular surgery is associated with a higher rate of morbidity and mortality. Delaying procedures in RT-PCR-positive patients may help reduce risks of perioperative complications and death.
5.
Caracterização Histológica das Lesões da Valva Mitral de Pacientes com Cardiopatia Reumática
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Gomes, Nayana F. A.
; Pascoal-Xavier, Marcelo A.
; Passos, Livia S. A.
; Paula, Thiago Mendonça Nunes
; Aguiar, João Marcelo de Souza
; Guarçoni, Felipe Vieira
; Nassif, Maria Cecília Landim
; Gelape, Claudio Leo
; Braulio, Renato
; Costa, Paulo Henrique N.
; Passaglia, Luiz Guilherme
; Martins, Raquel Braga
; Dutra, Walderez O.
; Nunes, Maria Carmo P.
.
Resumo Fundamentos: Os mecanismos subjacentes pelos quais a doença cardíaca reumática (DCR) levam à disfunção valvar grave não são totalmente compreendidos. Objetivo: O presente estudo avaliou as alterações histopatológicas nas valvas mitrais (VM) buscando uma associação entre o padrão de disfunção valvar predominante e os achados histopatológicos. Métodos: Em 40 pacientes submetidos à troca da VM devido a DCR e em 20 controles submetidos a transplante cardíaco, foram analisados os aspectos histológicos da VM excisada. Dados clínicos e ecocardiográficos também foram coletados. As análises histológicas foram realizadas usando coloração com hematoxilina-eosina. Determinou-se inflamação, fibrose, neoangiogênese, calcificação e metaplasia adiposa. Valores de p<0,05 foram considerados estatisticamente significativos. Resultados: A idade média dos pacientes com DCR foi de 53±13 anos, sendo 36 (90%) do sexo feminino, enquanto a idade média dos controles foi de 50±12 anos, semelhante aos casos, sendo a maioria do sexo masculino (70%). O endocárdio valvar reumático apresentou espessura maior que os controles (1,3±0,5 mm versus 0,90±0,4 mm, p=0,003, respectivamente), e infiltrado inflamatório mais intenso no endocárdio (78% versus 36%; p=0,004), com predominância de células mononucleares. Ocorreu fibrose moderada a acentuada mais frequentemente em válvulas reumáticas do que em válvulas controle (100% vs. 29%; p<0,001). Ocorreu calcificação em 35% das valvas reumáticas, principalmente entre as valvas estenóticas, associada à área valvar mitral (p=0,003). Conclusões: Apesar do intenso grau de fibrose, o processo inflamatório permanece ativo na valva mitral reumática, mesmo em doença tardia com disfunção valvar. A calcificação predominou em valvas estenóticas e em pacientes com disfunção ventricular direita.
Abstract Background: The underlying mechanisms by which rheumatic heart disease (RHD) lead to severe valve dysfunction are not completely understood. Objective: The present study evaluated the histopathological changes in mitral valves (MV) seeking an association between the pattern of predominant valvular dysfunction and histopathological findings. Methods: In 40 patients who underwent MV replacement due to RHD, and in 20 controls that underwent heart transplant, histological aspects of the excised MV were analyzed. Clinical and echocardiographic data were also collected. Histological analyses were performed using hematoxylin-eosin staining. Inflammation, fibrosis, neoangiogenesis, calcification and adipose metaplasia were determined. A p value<0.05 was considered to be statistically significant. Results: The mean age of RHD patients was 53±13 years, 36 (90%) were female, whereas the mean age of controls was 50±12 years, similar to the cases, with the majority of males (70%). The rheumatic valve endocardium presented greater thickness than the controls (1.3±0.5 mm versus 0.90±0.4 mm, p=0.003, respectively), and a more intense inflammatory infiltrate in the endocardium (78% versus 36%; p=0.004), with predominance of mononuclear cells. Moderate to marked fibrosis occurred more frequently in rheumatic valves than in control valves (100% vs. 29%; p<0.001). Calcification occurred in 35% of rheumatic valves, especially among stenotic valves, which was associated with the mitral valve area (p=0.003). Conclusions: Despite intense degree of fibrosis, the inflammatory process remains active in the rheumatic mitral valve, even at late disease with valve dysfunction. Calcification predominated in stenotic valves and in patients with right ventricular dysfunction.
https://doi.org/10.36660/abc.20200154
542 downloads
6.
The Program for Biodiversity Research in Brazil: The role of regional networks for biodiversity knowledge, dissemination, and conservation
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ROSA, CLARISSA
; BACCARO, FABRICIO
; CRONEMBERGER, CECILIA
; HIPÓLITO, JULIANA
; BARROS, CLAUDIA FRANCA
; RODRIGUES, DOMINGOS DE JESUS
; NECKEL-OLIVEIRA, SELVINO
; OVERBECK, GERHARD E.
; DRECHSLER-SANTOS, ELISANDRO RICARDO
; ANJOS, MARCELO RODRIGUES DOS
; FERREGUETTI, ÁTILLA C.
; AKAMA, ALBERTO
; MARTINS, MARLÚCIA BONIFÁCIO
; TOMAS, WALFRIDO MORAES
; SANTOS, SANDRA APARECIDA
; FERREIRA, VANDA LÚCIA
; CUNHA, CATIA NUNES DA
; PENHA, JERRY
; PINHO, JOÃO BATISTA DE
; SALIS, SUZANA MARIA
; DORIA, CAROLINA RODRIGUES DA COSTA
; PILLAR, VALÉRIO D.
; PODGAISKI, LUCIANA R.
; MENIN, MARCELO
; BÍGIO, NARCÍSIO COSTA
; ARAGÓN, SUSAN
; MANZATTO, ANGELO GILBERTO
; VÉLEZ-MARTIN, EDUARDO
; SILVA, ANA CAROLINA BORGES LINS E
; IZZO, THIAGO JUNQUEIRA
; MORTATI, AMANDA FREDERICO
; GIACOMIN, LEANDRO LACERDA
; ALMEIDA, THAÍS ELIAS
; ANDRÉ, THIAGO
; SILVEIRA, MARIA AUREA PINHEIRO DE ALMEIDA
; SILVEIRA, ANTÔNIO LAFFAYETE PIRES DA
; MESSIAS, MARILUCE REZENDE
; MARQUES, MARCIA C.M.
; PADIAL, ANDRE ANDRIAN
; MARQUES, RENATO
; BITAR, YOUSZEF O.C.
; SILVEIRA, MARCOS
; MORATO, ELDER FERREIRA
; PAGOTTO, RUBIANI DE CÁSSIA
; STRUSSMANN, CHRISTINE
; MACHADO, RICARDO BOMFIM
; AGUIAR, LUDMILLA MOURA DE SOUZA
; FERNANDES, GERALDO WILSON
; OKI, YUMI
; NOVAIS, SAMUEL
; FERREIRA, GUILHERME BRAGA
; BARBOSA, FLÁVIA RODRIGUES
; OCHOA, ANA C.
; MANGIONE, ANTONIO M.
; GATICA, AILIN
; CARRIZO, MARÍA CELINA
; RETTA, LUCÍA MARTINEZ
; JOFRÉ, LAURA E.
; CASTILLO, LUCIANA L.
; NEME, ANDREA M.
; RUEDA, CARLA
; TOLEDO, JOSÉ JULIO DE
; GRELLE, CARLOS EDUARDO VIVEIROS
; VALE, MARIANA M.
; VIEIRA, MARCUS VINICIUS
; CERQUEIRA, RUI
; HIGASHIKAWA, EMÍLIO MANABU
; MENDONÇA, FERNANDO PEREIRA DE
; GUERREIRO, QUÊZIA LEANDRO DE MOURA
; BANHOS, AUREO
; HERO, JEAN-MARC
; KOBLITZ, RODRIGO
; COLLEVATTI, ROSANE GARCIA
; SILVEIRA, LUÍS FÁBIO
; VASCONCELOS, HERALDO L.
; VIEIRA, CECÍLIA RODRIGUES
; COLLI, GUARINO RINALDI
; CECHIN, SONIA ZANINI
; SANTOS, TIAGO GOMES DOS
; FONTANA, CARLA S.
; JARENKOW, JOÃO A.
; MALABARBA, LUIZ R.
; RUEDA, MARTA P.
; ARAUJO, PUBLIO A.
; PALOMO, LUCAS
; ITURRE, MARTA C.
; BERGALLO, HELENA GODOY
; MAGNUSSON, WILLIAM E.
.
Abstract The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.
https://doi.org/10.1590/0001-3765202120201604
1034 downloads
7.
O MÉTODO DE HYLLERAAS PARA ÁTOMOS DE DOIS ELÉTRONS
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The quantum mechanics of two electrons atoms, as suggested by E. A. Hylleraas in the period between 1928-1930, is discussed in the present work. Hylleraas introduced explicit correlations in the wavefunction by treating the coordinates between the electrons as an independent variable of the problem, an approach that gives very precise energy values. Solution of the problem is given for one, two, three and six basis functions, as in the original work. The solution is also carried out with 140 basis functions, showing that the energy for two electron atoms can be calculated with seven significant figures. Numerical methods presented here are accessible to undergraduated level students.
https://doi.org/10.21577/0100-4042.20170125
601 downloads
8.
PROBLEMAS INVERSOS MAL COLOCADOS EM QUÍMICA
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What is an ill-posed inverse problem? The answer to this question is the main objective of the present paper and the pre-requisite to follow the material requires only elementary calculus. The first mathematical formulation of an inverse problem, due to N. H. Abel, together with the fundamental work by Jacques Hadamard, are explored at the beginning of the paper. A prototype system is used to consider the regularization concept. Three numerical methods, the Tikhonov regularization, the decomposition into singular values and the Hopfield neural networks, applied to remove the singularity are examined. General aspects of the ill-posed inverse problems in chemistry with emphasis in thermodynamics and a set of general rules for other areas of science are also analyzed.
https://doi.org/10.5935/0100-4042.20160104
914 downloads
9.
COEFICIENTES DE TRANSMISSÃO E REFLEXÃO PELO MÉTODO DA AMPLITUDE VARIÁVEL
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In this work, a simple derivation of the variable amplitude method using the variation of parameters to solve a differential equation is presented. The variable amplitude method was originally devised by Tikochinsky in 1977, using the quantum theory of scattering. The method is applied to two model potentials, the rectangular potential barrier and the Eckart potential, both with analytical solutions for the reflection coefficient. Numerical results will be compared with the exact values for several energies. The problem of calculating the reflection coefficient, usually involving extensive algebra as described in several textbooks, is reduced to solving a first order differential equation with initial condition. The method is very simple to apply, representing an attractive tool for teaching introductory quantum mechanics. A simple computer code is available from which reflection coefficients for the Eckart potential can be calculated.
https://doi.org/10.5935/0100-4042.20160061
1409 downloads
10.
Atheroprotective action of a modified organoselenium compound: in vitro evidence
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OLIVEIRA, JADE DE
; STRALIOTTO, MARCOS R.
; MANCINI, GIANNI
; FIGUEIREDO, CLAUDIA P.
; BRAGA, ANTÔNIO L.
; TEIXEIRA, JOÃO B.R.
; BEM, ANDREZA F.
.
RESUMO A oxidação da lipoproteína de baixa densidade (LDL) apresenta um papel importante na patogênese da aterosclerose. Nesse sentido, reduzir a oxidação da LDL é uma abordagem importante para diminuir o risco de aterosclerose. Compostos orgânicos de selênio têm demonstrado propriedades ateroprotetoras promissoras em modelos experimentais. Neste estudo, nós testamos a capacidade ateroprotetora in vitro de um composto orgânico de selênio modificado, Composto HBD, em proteger a LDL isolada da oxidação, bem como a formação de células espumosas. Além disso, a atividade mimética da enzima glutationa peroxidase (GPx) do composto HBD foi analisada com o intuito de explorar os mecanismos relacionados com os efeitos protetores apresentados pelo Composto HBD. O Composto HBD reduziu a formação de dienos conjugados induzida pelo Cu2+ em uma maneira dependente da concentração. A parte proteica da LDL também foi protegida da oxidação induzida pelo Cu2+. Além disso, o composto HBD eficientemente diminuiu a formação de células espumosas em macrófagos J774 expostos à LDL oxidada. Nós observamos que os efeitos ateroprotetores deste composto podem ser, ao menos em parte, relacionados à sua atividade mimética da GPx. Nossos resultados demonstraram um efeito in vitro promissor do Composto HBD em reduzir a toxicidade induzida pela LDL. Nesse sentido, um outro estudo in vivo para investigar de maneira mais detalhada os efeitos antioxidantes e ateroprotetores deste composto pode ser considerado.
ABSTRACT Oxidation of low-density lipoprotein (LDL) has been strongly suggested to play a significant role in the pathogenesis of atherosclerosis. Thus, reducing LDL oxidation is a potential approach to decrease the risk of the atherosclerosis. Organoselenium compounds have demonstrated promising atheroprotective properties in experimental models. Herein, we tested the in vitro atheroprotective capability of a modified organoselenium compound, Compound HBD, in protecting isolated LDL from oxidation as well as foam cells formation. Moreover, the glutathione peroxidase (GPx)-like activity of Compound HBD was analyzed in order to explore the mechanisms related to the above-mentioned protective effects. The Compound HBD in a concentration-dependent manner reduced the Cu2+-induced formation of conjugated dienes. The protein portion from LDL were also protected from Cu2+-induced oxidation. Furthermore, the Compound HBD efficiently decreased the foam cell formation in J774 macrophage cells exposed to oxidized LDL. We found that the atheroprotective effects of this compound can be, at least in part, related to its GPx-like activity. Our findings demonstrated an impressive effect of Compound HBD against LDL-induced toxicity, a further in vivo study to investigate in more detail the antioxidant and antiatherogenic effects of this compound could be considered.
https://doi.org/10.1590/0001-3765201620150760
1147 downloads
11.
Metalloproteomic Profile Determination of Muscle Samples from Nile Tilapia (Oreochromis niloticus) Using AAS and ESI-MS/MS after 2D-PAGE Separation
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Cavecci, Bruna
; Lima, Paula M. de
; Queiroz, João V. de
; Braga, Camila P.
; Padilha, Cilene C. F.
; Leite, Aline L.
; Buzalaf, Marília A. R.
; Pezzato, Luiz E.
; Padilha, Pedro M.
.
This study evaluated the metalloproteomic profile of muscle tissue samples from Nile tilapia (Oreochromis niloticus). Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) methods was used for protein fractionation and identification based on image analysis. Determination of Ca, Cu, Fe, Mn and Zn was performed in the protein spots by flame and/or graphite furnace atomic absorption spectrometry (FAAS, GFAAS), the protein spots were characterized by electrospray ionization-tandem mass spectrometry (ESI-MS/MS). FAAS and GFAAS determinations have indicated the presence of calcium in seven protein spots, iron in only one spot, manganese in six spots, and zinc in two spots. Of the seventeen protein spots where the presence of metal ions was detected, ten were characterized by ESI-MS/MS.
https://doi.org/10.5935/0103-5053.20140260
1453 downloads
12.
Growing knowledge: an overview of Seed Plant diversity in Brazil
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Zappi, Daniela C.
; Filardi, Fabiana L. Ranzato
; Leitman, Paula
; Souza, Vinícius C.
; Walter, Bruno M.T.
; Pirani, José R.
; Morim, Marli P.
; Queiroz, Luciano P.
; Cavalcanti, Taciana B.
; Mansano, Vidal F.
; Forzza, Rafaela C.
; Abreu, Maria C.
; Acevedo-Rodríguez, Pedro
; Agra, Maria F.
; Almeida Jr., Eduardo B.
; Almeida, Gracineide S.S.
; Almeida, Rafael F.
; Alves, Flávio M.
; Alves, Marccus
; Alves-Araujo, Anderson
; Amaral, Maria C.E.
; Amorim, André M.
; Amorim, Bruno
; Andrade, Ivanilza M.
; Andreata, Regina H.P.
; Andrino, Caroline O.
; Anunciação, Elisete A.
; Aona, Lidyanne Y.S.
; Aranguren, Yani
; Aranha Filho, João L.M.
; Araújo, Andrea O.
; Araújo, Ariclenes A.M.
; Araújo, Diogo
; Arbo, María M.
; Assis, Leandro
; Assis, Marta C.
; Assunção, Vivian A.
; Athiê-Souza, Sarah M.
; Azevedo, Cecilia O.
; Baitello, João B.
; Barberena, Felipe F.V.A.
; Barbosa, Maria R.V.
; Barros, Fábio
; Barros, Lucas A.V.
; Barros, Michel J.F.
; Baumgratz, José F.A.
; Bernacci, Luis C.
; Berry, Paul E.
; Bigio, Narcísio C.
; Biral, Leonardo
; Bittrich, Volker
; Borges, Rafael A.X.
; Bortoluzzi, Roseli L.C.
; Bove, Cláudia P.
; Bovini, Massimo G.
; Braga, João M.A.
; Braz, Denise M.
; Bringel Jr., João B.A.
; Bruniera, Carla P.
; Buturi, Camila V.
; Cabral, Elza
; Cabral, Fernanda N.
; Caddah, Mayara K.
; Caires, Claudenir S.
; Calazans, Luana S.B.
; Calió, Maria F.
; Camargo, Rodrigo A.
; Campbell, Lisa
; Canto-Dorow, Thais S.
; Carauta, Jorge P.P.
; Cardiel, José M.
; Cardoso, Domingos B.O.S.
; Cardoso, Leandro J.T.
; Carneiro, Camila R.
; Carneiro, Cláudia E.
; Carneiro-Torres, Daniela S.
; Carrijo, Tatiana T.
; Caruzo, Maria B.R.
; Carvalho, Maria L.S.
; Carvalho-Silva, Micheline
; Castello, Ana C.D.
; Cavalheiro, Larissa
; Cervi, Armando C.
; Chacon, Roberta G.
; Chautems, Alain
; Chiavegatto, Berenice
; Chukr, Nádia S.
; Coelho, Alexa A.O.P.
; Coelho, Marcus A.N.
; Coelho, Rubens L.G.
; Cordeiro, Inês
; Cordula, Elizabeth
; Cornejo, Xavier
; Côrtes, Ana L.A.
; Costa, Andrea F.
; Costa, Fabiane N.
; Costa, Jorge A.S.
; Costa, Leila C.
; Costa-e-Silva, Maria B.
; Costa-Lima, James L.
; Cota, Maria R.C.
; Couto, Ricardo S.
; Daly, Douglas C.
; De Stefano, Rodrigo D.
; De Toni, Karen
; Dematteis, Massimiliano
; Dettke, Greta A.
; Di Maio, Fernando R.
; Dórea, Marcos C.
; Duarte, Marília C.
; Dutilh, Julie H.A.
; Dutra, Valquíria F.
; Echternacht, Lívia
; Eggers, Lilian
; Esteves, Gerleni
; Ezcurra, Cecilia
; Falcão Junior, Marcus J.A.
; Feres, Fabíola
; Fernandes, José M.
; Ferreira, D.M.C.
; Ferreira, Fabrício M.
; Ferreira, Gabriel E.
; Ferreira, Priscila P.A.
; Ferreira, Silvana C.
; Ferrucci, Maria S.
; Fiaschi, Pedro
; Filgueiras, Tarciso S.
; Firens, Marcela
; Flores, Andreia S.
; Forero, Enrique
; Forster, Wellington
; Fortuna-Perez, Ana P.
; Fortunato, Reneé H.
; Fraga, Cléudio N.
; França, Flávio
; Francener, Augusto
; Freitas, Joelcio
; Freitas, Maria F.
; Fritsch, Peter W.
; Furtado, Samyra G.
; Gaglioti, André L.
; Garcia, Flávia C.P.
; Germano Filho, Pedro
; Giacomin, Leandro
; Gil, André S.B.
; Giulietti, Ana M.
; A.P.Godoy, Silvana
; Goldenberg, Renato
; Gomes da Costa, Géssica A.
; Gomes, Mário
; Gomes-Klein, Vera L.
; Gonçalves, Eduardo Gomes
; Graham, Shirley
; Groppo, Milton
; Guedes, Juliana S.
; Guimarães, Leonardo R.S.
; Guimarães, Paulo J.F.
; Guimarães, Elsie F.
; Gutierrez, Raul
; Harley, Raymond
; Hassemer, Gustavo
; Hattori, Eric K.O.
; Hefler, Sonia M.
; Heiden, Gustavo
; Henderson, Andrew
; Hensold, Nancy
; Hiepko, Paul
; Holanda, Ana S.S.
; Iganci, João R.V.
; Imig, Daniela C.
; Indriunas, Alexandre
; Jacques, Eliane L.
; Jardim, Jomar G.
; Kamer, Hiltje M.
; Kameyama, Cíntia
; Kinoshita, Luiza S.
; Kirizawa, Mizué
; Klitgaard, Bente B.
; Koch, Ingrid
; Koschnitzke, Cristiana
; Krauss, Nathália P.
; Kriebel, Ricardo
; Kuntz, Juliana
; Larocca, João
; Leal, Eduardo S.
; Lewis, Gwilym P.
; Lima, Carla T.
; Lima, Haroldo C.
; Lima, Itamar B.
; Lima, Laíce F.G.
; Lima, Laura C.P.
; Lima, Leticia R.
; Lima, Luís F.P.
; Lima, Rita B.
; Lírio, Elton J.
; Liro, Renata M.
; Lleras, Eduardo
; Lobão, Adriana
; Loeuille, Benoit
; Lohmann, Lúcia G.
; Loiola, Maria I.B.
; Lombardi, Julio A.
; Longhi-Wagner, Hilda M.
; Lopes, Rosana C.
; Lorencini, Tiago S.
; Louzada, Rafael B.
; Lovo, Juliana
; Lozano, Eduardo D.
; Lucas, Eve
; Ludtke, Raquel
; Luz, Christian L.
; Maas, Paul
; Machado, Anderson F.P.
; Macias, Leila
; Maciel, Jefferson R.
; Magenta, Mara A.G.
; Mamede, Maria C.H.
; Manoel, Evelin A.
; Marchioretto, Maria S.
; Marques, Juliana S.
; Marquete, Nilda
; Marquete, Ronaldo
; Martinelli, Gustavo
; Martins da Silva, Regina C.V.
; Martins, Ângela B.
; Martins, Erika R.
; Martins, Márcio L.L.
; Martins, Milena V.
; Martins, Renata C.
; Matias, Ligia Q.
; Maya-L., Carlos A.
; Mayo, Simon
; Mazine, Fiorella
; Medeiros, Debora
; Medeiros, Erika S.
; Medeiros, Herison
; Medeiros, João D.
; Meireles, José E.
; Mello-Silva, Renato
; Melo, Aline
; Melo, André L.
; Melo, Efigênia
; Melo, José I.M.
; Menezes, Cristine G.
; Menini Neto, Luiz
; Mentz, Lilian A.
; Mezzonato, A.C.
; Michelangeli, Fabián A.
; Milward-de-Azevedo, Michaele A.
; Miotto, Silvia T.S.
; Miranda, Vitor F.O.
; Mondin, Cláudio A.
; Monge, Marcelo
; Monteiro, Daniele
; Monteiro, Raquel F.
; Moraes, Marta D.
; Moraes, Pedro L.R.
; Mori, Scott A.
; Mota, Aline C.
; Mota, Nara F.O.
; Moura, Tania M.
; Mulgura, Maria
; Nakajima, Jimi N.
; Nardy, Camila
; Nascimento Júnior, José E.
; Noblick, Larry
; Nunes, Teonildes S.
; O'Leary, Nataly
; Oliveira, Arline S.
; Oliveira, Caetano T.
; Oliveira, Juliana A.
; Oliveira, Luciana S.D.
; Oliveira, Maria L.A.A.
; Oliveira, Regina C.
; Oliveira, Renata S.
; Oliveira, Reyjane P.
; Paixão-Souza, Bruno
; Parra, Lara R.
; Pasini, Eduardo
; Pastore, José F.B.
; Pastore, Mayara
; Paula-Souza, Juliana
; Pederneiras, Leandro C.
; Peixoto, Ariane L.
; Pelissari, Gisela
; Pellegrini, Marco O.O.
; Pennington, Toby
; Perdiz, Ricardo O.
; Pereira, Anna C.M.
; Pereira, Maria S.
; Pereira, Rodrigo A.S.
; Pessoa, Clenia
; Pessoa, Edlley M.
; Pessoa, Maria C.R.
; Pinto, Luiz J.S.
; Pinto, Rafael B.
; Pontes, Tiago A.
; Prance, Ghillean T.
; Proença, Carolyn
; Profice, Sheila R.
; Pscheidt, Allan C.
; Queiroz, George A.
; Queiroz, Rubens T.
; Quinet, Alexandre
; Rainer, Heimo
; Ramos, Eliana
; Rando, Juliana G.
; Rapini, Alessandro
; Reginato, Marcelo
; Reis, Ilka P.
; Reis, Priscila A.
; Ribeiro, André R.O.
; Ribeiro, José E.L.S.
; Riina, Ricarda
; Ritter, Mara R.
; Rivadavia, Fernando
; Rocha, Antônio E.S.
; Rocha, Maria J.R.
; Rodrigues, Izabella M.C.
; Rodrigues, Karina F.
; Rodrigues, Rodrigo S.
; Rodrigues, Rodrigo S.
; Rodrigues, Vinícius T.
; Rodrigues, William
; Romaniuc Neto, Sérgio
; Romão, Gerson O.
; Romero, Rosana
; Roque, Nádia
; Rosa, Patrícia
; Rossi, Lúcia
; Sá, Cyl F.C.
; Saavedra, Mariana M.
; Saka, Mariana
; Sakuragui, Cássia M.
; Salas, Roberto M.
; Sales, Margareth F.
; Salimena, Fatima R.G.
; Sampaio, Daniela
; Sancho, Gisela
; Sano, Paulo T.
; Santos, Alessandra
; Santos, Élide P.
; Santos, Juliana S.
; Santos, Marianna R.
; Santos-Gonçalves, Ana P.
; Santos-Silva, Fernanda
; São-Mateus, Wallace
; Saraiva, Deisy P.
; Saridakis, Dennis P.
; Sartori, Ângela L.B.
; Scalon, Viviane R.
; Schneider, Ângelo
; Sebastiani, Renata
; Secco, Ricardo S.
; Senna, Luisa
; Senna-Valle, Luci
; Shirasuna, Regina T.
; Silva Filho, Pedro J.S.
; Silva, Anádria S.
; Silva, Christian
; Silva, Genilson A.R.
; Silva, Gisele O.
; Silva, Márcia C.R.
; Silva, Marcos J.
; Silva, Marcos J.
; Silva, Otávio L.M.
; Silva, Rafaela A.P.
; Silva, Saura R.
; Silva, Tania R.S.
; Silva-Gonçalves, Kelly C.
; Silva-Luz, Cíntia L.
; Simão-Bianchini, Rosângela
; Simões, André O.
; Simpson, Beryl
; Siniscalchi, Carolina M.
; Siqueira Filho, José A.
; Siqueira, Carlos E.
; Siqueira, Josafá C.
; Smith, Nathan P.
; Snak, Cristiane
; Soares Neto, Raimundo L.
; Soares, Kelen P.
; Soares, Marcos V.B.
; Soares, Maria L.
; Soares, Polyana N.
; Sobral, Marcos
; Sodré, Rodolfo C.
; Somner, Genise V.
; Sothers, Cynthia A.
; Sousa, Danilo J.L.
; Souza, Elnatan B.
; Souza, Élvia R.
; Souza, Marcelo
; Souza, Maria L.D.R.
; Souza-Buturi, Fátima O.
; Spina, Andréa P.
; Stapf, María N.S.
; Stefano, Marina V.
; Stehmann, João R.
; Steinmann, Victor
; Takeuchi, Cátia
; Taylor, Charlotte M.
; Taylor, Nigel P.
; Teles, Aristônio M.
; Temponi, Lívia G.
; Terra-Araujo, Mário H.
; Thode, Veronica
; Thomas, W.Wayt
; Tissot-Squalli, Mara L.
; Torke, Benjamin M.
; Torres, Roseli B.
; Tozzi, Ana M.G.A.
; Trad, Rafaela J.
; Trevisan, Rafael
; Trovó, Marcelo
; Valls, José F.M.
; Vaz, Angela M.S.F.
; Versieux, Leonardo
; Viana, Pedro L.
; Vianna Filho, Marcelo D.M.
; Vieira, Ana O.S.
; Vieira, Diego D.
; Vignoli-Silva, Márcia
; Vilar, Thaisa
; Vinhos, Franklin
; Wallnöfer, Bruno
; Wanderley, Maria G.L.
; Wasshausen, Dieter
; Watanabe, Maurício T.C.
; Weigend, Maximilian
; Welker, Cassiano A.D.
; Woodgyer, Elizabeth
; Xifreda, Cecilia C.
; Yamamoto, Kikyo
; Zanin, Ana
; Zenni, Rafael D.
; Zickel, Carmem S
.
Resumo Um levantamento atualizado das plantas com sementes e análises relevantes acerca desta biodiversidade são apresentados. Este trabalho se iniciou em 2010 com a publicação do Catálogo de Plantas e Fungos e, desde então vem sendo atualizado por mais de 430 especialistas trabalhando online. O Brasil abriga atualmente 32.086 espécies nativas de Angiospermas e 23 espécies nativas de Gimnospermas e estes novos dados mostram um aumento de 3% da riqueza em relação a 2010. A Amazônia é o Domínio Fitogeográfico com o maior número de espécies de Gimnospermas, enquanto que a Floresta Atlântica possui a maior riqueza de Angiospermas. Houve um crescimento considerável no número de espécies e nas taxas de endemismo para a maioria dos Domínios (Caatinga, Cerrado, Floresta Atlântica, Pampa e Pantanal), com exceção da Amazônia que apresentou uma diminuição de 2,5% de endemicidade. Entretanto, a maior parte das plantas com sementes que ocorrem no Brasil (57,4%) é endêmica deste território. A proporção de formas de vida varia de acordo com os diferentes Domínios: árvores são mais expressivas na Amazônia e Floresta Atlântica do que nos outros biomas, ervas são dominantes no Pampa e as lianas apresentam riqueza expressiva na Amazônia, Floresta Atlântica e Pantanal. Este trabalho não só quantifica a biodiversidade brasileira, mas também indica as lacunas de conhecimento e o desafio a ser enfrentado para a conservação desta flora.
Abstract An updated inventory of Brazilian seed plants is presented and offers important insights into the country's biodiversity. This work started in 2010, with the publication of the Plants and Fungi Catalogue, and has been updated since by more than 430 specialists working online. Brazil is home to 32,086 native Angiosperms and 23 native Gymnosperms, showing an increase of 3% in its species richness in relation to 2010. The Amazon Rainforest is the richest Brazilian biome for Gymnosperms, while the Atlantic Rainforest is the richest one for Angiosperms. There was a considerable increment in the number of species and endemism rates for biomes, except for the Amazon that showed a decrease of 2.5% of recorded endemics. However, well over half of Brazillian seed plant species (57.4%) is endemic to this territory. The proportion of life-forms varies among different biomes: trees are more expressive in the Amazon and Atlantic Rainforest biomes while herbs predominate in the Pampa, and lianas are more expressive in the Amazon, Atlantic Rainforest, and Pantanal. This compilation serves not only to quantify Brazilian biodiversity, but also to highlight areas where there information is lacking and to provide a framework for the challenge faced in conserving Brazil's unique and diverse flora.
https://doi.org/10.1590/2175-7860201566411
33340 downloads
13.
Variable phase equation in quantum scattering
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Este artigo apresenta a dedução e aplicações da equação da fase variável para o caso de um canal no espalhamento quântico. Esta abordagem foi apresentada pela primeira vez em 1933 por Morse e Allis e baseia-se numa modificação da equação Schrödinger para uma equação diferencial de primeira ordem, adequada para o problema de espalhamento. A dependência do deslocamento de fase com o momento angular e a energia, juntamente com o teorema de Levinson, é discutida. A equação resultante do método da fase variável é de fácil programação e pode ser explorado em cursos introdutórios de mecânica quântica.
This paper presents the derivation and applications of the variable phase equation for single channel quantum scattering. The approach was first presented in 1933 by Morse and Allis and is based on a modification of the Schrödinger equation to a first order differential equation, appropriate to the scattering problem. The dependence of phase shift on angular momentum and energy, together with Levinson's theorem, is discussed. Because the variable phase equation method is easy to program it can be further explored in an introductory quantum mechanics course.
1965 downloads
14.
Quantum second virial coefficient calculation for the 4He dimer on a recent potential
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Costa, Éderson D'Martin
; Lemes, Nelson H. T.
; Alves, Márcio O.
; Sebastião, Rita C. O.
; Braga, João P.
.
Este trabalho concentra-se no cálculo do segundo coeficiente virial quântico, a partir de um potencial desenvolvido recentemente. Este coeficiente foi determinado com 4-5 algarismos significativos na faixa de temperatura de 3 a 100 K. Nossos resultados estão dentro do erro experimental. Três contribuições para o valor total deste coeficiente são o espalhamento quântico (contribuição de estados no contínuo), o estado ligado (contribuição de estados discretos) e o gás ideal quântico; discutimos estas contribuições separadamente. A contribuição mais importante é do espalhamento quântico, enquanto que as contribuições menores são dos estados discretos. Uma análise da sensibilidade foi realizada em função da temperatura para um parâmetro na região de curto alcance do potencial e para três parâmetros na região de longo alcance do potencial. Para ambas as temperaturas consideradas, 10 e 100 K, o coeficiente de dispersão C6 foi o mais significativo, e o termo dispersão C10 foi o menos significativo para o resultado total. Em geral, a precisão exigida para descrever os potenciais diminui com o aumento da temperatura. A precisão total e a relação dos parâmetros com os erros experimentais são discutidas.
This paper focuses on the calculation of the quantum second virial coefficient, under a recently developed potential. This coefficient was determined to within 4-5 significant figures in the temperature range from 3 to 100 K. Our results are within experimental error. The three contributions to the overall value of the coefficient are the quantum scattering (continuum state contribution), the bound state (discrete state contribution) and the quantum ideal gas; we discuss these contributions separately. The most significant contribution is from the scattering states, whereas the smaller contributions are from the discrete states. A sensitivity analysis was performed as a function of temperature for one parameter in the short-range region of the potential and for three parameters in the long-range regions of the potential. For both temperatures considered, 10 and 100 K, the C6 dispersion coefficient was the most significant, and the C10 dispersion term was the least significant to the overall result. In general, the precision required to describe the potential decays as the temperature increases. The overall accuracy and the relationship of the parameters to the experimental errors are discussed.
https://doi.org/10.5935/0103-5053.20130046
2605 downloads
15.
Methane combustion kinetic rate constants determination: an ill-posed inverse problem analysis
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Ferreira, Bárbara D. L.
; Paulo, Jaqueline M.
; Braga, João P.
; Sebastião, Rita C. O.
; Pujatti, Fabrício J. P.
.
Methane combustion was studied by the Westbrook and Dryer model. This well-established simplified mechanism is very useful in combustion science, for computational effort can be notably reduced. In the inversion procedure to be studied, rate constants are obtained from [CO] concentration data. However, when inherent experimental errors in chemical concentrations are considered, an ill-conditioned inverse problem must be solved for which appropriate mathematical algorithms are needed. A recurrent neural network was chosen due to its numerical stability and robustness. The proposed methodology was compared against Simplex and Levenberg-Marquardt, the most used methods for optimization problems.
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aff_country | country code of the author's affiliation |
aff_institution | author affiliation institution |
volume | article volume |
issue | article issue |
elocation | elocation |
doi | DOI number |
issn | journal ISSN |
in | SciELO colection code (e.g. scl - Brasil, col - Colômbia) |
use_license | article usage license code |