REPOSITÓRIO DIGITAL DA PRODUÇÃO TÉCNICO CIENTÍFICA

 

 

 

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O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos. [Saiba mais]

 

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  • IPEN-DOC 27147

    SOUZA, A.P.S.; OLIVEIRA, L.P. de; YOKAICHIYA, F.; GENEZINI, F.A. ; FRANCO, M.K.K.D. . Neutron Guide Building instruments of the Brazilian Multipurpose Reactor (RMB) project. Journal of Instrumentation, v. 15, n. 4, p. 1-24, 2020. DOI: 10.1088/1748-0221/15/04/P04011

    Abstract: A growing community of scientists has been using neutrons in the most diverse areas of science. In order to meet the researchers demand in the areas of physics, chemistry, materials sciences, engineering, cultural heritage, biology and earth sciences, the Brazilian Multipurpose Reactor (RMB) will provide 3 thermal guides and 3 cold guides, with the installation of several instruments for materials characterization. In this study, we present a standard design requirement of two primordial instruments, namely Sabiá and Araponga. They are, respectively, cold and thermal neutron instruments and correspond to a Small-Angle Neutron Scattering (SANS) and High-Resolution Powder Neutron Diffractometer (HRPND) to be installed in the Neutron Guide Building (N02) of RMB. To provide adequate flux for both instruments, we propose here an initial investigation of the use of simple and split guides to transport neutron beams to two different instruments on the same guide. For this purpose, we use Monte Carlo simulations utilizing McStas software to check the efficiency of thermal neutron transport for different basic configuration and sources. By considering these results, it is possible to conclude that the split guide configuration is, in most cases, more efficient than cases that use transmitted neutron beams independently of source. We also verify that the employment of different coating indexes for concave and convex surfaces on curved guides is crucial, at least on simulated cases, to optimise neutron flux (intensity and divergence) and diminish facility installation cost.

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  • IPEN-DOC 27146

    OLIVEIRA, L.P. de; SOUZA, A.P.S.; YOKAICHIYA, F.; GENEZINI, F.A. ; FRANCO, M.K.K.D. . Monte Carlo simulations of the S-shaped neutron guide. Journal of Instrumentation, v. 15, n. 1, p. 1-14, 2020. DOI: 10.1088/1748-0221/15/01/P01012

    Abstract: Neutron transport along guides is governed by the Liouville theorem and the technology involved has advanced in recent decades. Computer simulations have proven to be useful tools in the design and conception of neutron guide systems in facilities. In this study, we use a Monte Carlo method to perform simulations for an S-shaped neutron guide with different dimensions for a Small-Angle Neutron Scattering (SANS) instrument, through the MCSTAS software. Awavelength cutoff is observed and shown to be dependent on the geometrical parameters of the guide. Results for the neutron flux at sample position are presented and greater sensitivity of cutoffs concerning the curvatures of the guides than to their lengths is noticed. Our results are in agreement with those obtained from the Acceptance Diagram method and we analyse the beam divergence behaviour along the S-shaped guide.

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  • IPEN-DOC 27137

    MONACO, DANIEL F. . FastLAP : desenvolvimento de um pré-processador gráfico visual para o código RELAP5 / FastLAP: development of a graphic visual preprocessor for RELAP5 . 2019. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 222 p. Orientador: Gaianê Sabundjian. DOI: 10.11606/D.85.2019.tde-05072019-144235

    Abstract: As energias limpas têm contribuído para o aumento de investimento e pesquisas em energia nuclear na última década. No entanto, as ocorrências dos acidentes nucleares ao longo da história ainda geram insegurança para a população em geral. Os órgãos reguladores têm aumentado as exigências de segurança em plantas nucleares e, devido a isto, vêm fazendo esforços na realização de simulações numéricas com programas computacionais de análise de acidentes em instalações nucleares, com a finalidade de garantir a segurança da planta e da população do entorno, antes mesmo de sua construção. No Brasil, para atender as exigências do órgão regulador brasileiro, a administradora dos reatores nucleares nacionais deve apresentar um estudo termo-hidráulico na área de análise de acidentes e transientes operacionais para as instalações nucleares. Isto é feito com a finalidade de licenciar as plantas nucleares, utilizando ferramentas computacionais apropriadas, tais como o código RELAP5. Esse programa computacional é muito eficiente na simulação de acidentes em usinas nucleares, mas não é muito amigável quanto à inserção de seus dados de entrada. Essa dificuldade motivou o desenvolvimento de pré-processadores para auxiliar a preparação dos dados geométricos de plantas nucleares, que é uma parte dos dados de entrada para o código RELAP5. Além disso, antes de iniciar o uso dessas ferramentas computacionais, faz-se necessário que o usuário monte uma nodalização ou modelagem do problema, de forma a representar mais adequadamente a planta e a fenomenologia envolvida durante um acidente ou transiente, sendo que ambas sejam adequadamente atendidas pela ferramenta. O objetivo desse trabalho foi o de criar um pré-processador capaz de auxiliar o usuário na tarefa de preparar os dados de entrada para o código RELAP5 e, também, de auxiliá-lo na elaboração da nodalização necessária para representar de forma mais real possível a planta em estudo. O pré-processador desenvolvido nesse trabalho é gráfico, visual e amigável, de forma a permitir que o usuário inicie a nodalização com o uso desta ferramenta, integrando assim as etapas de modelagem e preparação dos dados de entrada para o código RELAP5 em uma única fase, reduzindo assim, os esforços necessários para a sua realização, otimizando o tempo gasto. Para atingir esse objetivo, foi utilizado como plataforma de desenvolvimento o MS Excel®, uma ferramenta de planilha de cálculo eletrônica largamente utilizada, e foi construído para ele um complemento por meio da linguagem C# e da plataforma .NET. E através desta linguagem, seus recursos de orientação a objetos e total integração com a ferramenta MS Excel®, como Interop e Visual Studio Tools for Office (VSTO) integrados, foi possível um desenvolvimento mais rápido de uma ferramenta eficiente para essa finalidade, fazendo uso de recursos que não estariam disponíveis por meio do VBA (Visual Basic for Applications). O pré-processador desenvolvido nesse trabalho permite a criação da nodalização de um problema termo-hidráulico, onde os componentes hidrodinâmicos são desenhados por meio da automação de AutoShapes do MS Excel® e os dados de entrada desses componentes são alimentados por meio de caixas de diálogo amigáveis e funcionais. Uma vez que o pré-processador foi criado como um complemento para MS Excel®, as linhas de programação do pré-processador criado não ficam restritas a uma única planilha, facilitando sua atualização e redistribuição. O resultado obtido por meio desse trabalho foi o FastLAP, um pré-processador para RELAP5 visual, robusto e amigável. Por meio do FastLAP, criado nesse trabalho, reduziu-se o esforço do usuário do código RELAP5 tanto no preparo da nodalização como no preparo dos dados de entrada para o código, uma vez que a ferramenta é amigável e exibe tanto os nomes das propriedades conforme definidos pelo código RELAP5, bem como os nomes das grandezas físicas reais que estão sendo representadas. O pré-processador foi testado na elaboração da nodalização e dos dados de entrada do RELAP5 para um problema experimental encontrado na literatura e mostrou-se uma poderosa ferramenta gráfica, ajudando os usuários do RELAP5 a organizar visualmente os dados de entrada e oferecendo condições para analisar os resultados mais rapidamente. Esse trabalho criou não somente uma nova ferramenta de apoio para o usuário RELAP5, mas sim uma nova abordagem para a simulação de acidentes termo-hidráulicos com o código, fundindo as duas etapas: de nodalização e preparação dos dados de entrada.

    Palavras-Chave: simulation; functional models; reactor cooling systems; coupled reactor cores; reactor accidents; excursions; reactor safety; leak detectors; computer codes; graphical user interface; programming; input-output analysis; data visualization; process development units

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  • IPEN-DOC 27136

    MORAIS, CHRISTIANE S. de . Estudo da evolução das concentrações de metano na última década na Amazônia / Evolution of methane concentration in the last decade in the Amazon . 2019. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 66 p. Orientador: Luciana Vanni Gatti. DOI: 10.11606/D.85.2020.tde-21022020-135554

    Abstract: A mudança do uso da terra e o desmatamento para fins de produção agropecuária na Amazônia tem sido motivo de grande preocupação. Atualmente, os estudos acerca das emissões (naturais e antrópicas) de Gases de Efeito Estufa - GEE vêm se intensificando no meio científico. A proposta deste trabalho é realizar estudo da evolução das concentrações de metano no período entre 2010 a 2017 na Amazônia e realizar uma intercomparação entre as medidas de perfis verticais de avião e da coluna total de CH4 utilizando Espectrômetro de Absorção - FTIR nos anos de 2016 a 2017. As coletas do perfil vertical de avião foram realizadas na Floresta Amazônica em RBA (9,01°S, 64,72°O, região localizada entre as cidades de Porto Velho e Rio Branco). As medidas realizadas pelo FTIR foram feitas no município de Porto Velho 8,8°S, 63,9°O. As análises das medidas de perfil vertical de avião foram realizadas no Laboratório de Gases de Efeito Estufa - LaGEE, no Instituto Nacional de Pesquisas Espaciais - INPE, em São José dos Campos - SP, enquanto que as medidas do FTIR foram analisadas pelo Instituto de Aeoronomia da Bélgica (Belgian Institute for Space Aeronomy (BIRA-IASB)). As medidas obtidas nesse trabalho, revelam uma variação interanual com crescimento das concentrações de CH4 no decorrer dos anos. As concentrações de metano obtidas nos perfis verticais de avião são maiores nas alturas mais próximas da superfície, abaixo da camada limite planetária (< 1,5 km), o que é um indicativo que esta região da Amazônia contribui com as emissões de metano para a atmosfera, contudo, a taxa de crescimento das concentrações de CH4 do local de estudo (5,7 ppb ano-1), ainda é menor que a taxa média global (7,7 ppb ano-1). Os resultados da intercomparação entre as medidas de perfil de avião e do FTIR indicam que os perfis de avião validam os resultados obtidos pelo FTIR.

    Palavras-Chave: fourier analysis; emission spectroscopy; fourier transform spectrometers; infrared spectrometers; natural gas; methane; greenhouse gases; hydrocarbons; air pollution; climatic change; amazon river; brazil

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  • IPEN-DOC 27145

    MONTEIRO, LUCILENA R. ; LANGE, CAMILA N.; FREIRE, BRUNA M.; PEDRON, TATIANA; SILVA, JULIO J.C. da; MAGALHÃES JUNIOR, ARIANO M. de; PEGORARO, CAMILA; BUSANELLO, CARLOS; BATISTA, BRUNO L.. Inter- and intra-variability in the mineral content of rice varieties grown in various microclimatic regions of southern Brazil. Journal of Food Composition and Analysis, v. 92, p. 1-11, 2020. DOI: 10.1016/j.jfca.2020.103535

    Abstract: The most common goal for rice breeding is to improve the nutritional content and to reduce toxic components. Fourteen varieties of rice were grown for this purpose in six microclimatic regions in southern Brazil. The elemental composition of rice and As-Species were measured by ICP-MS and HPLC-ICP-MS, respectively. Intraand inter-species variations of essential and non-essential elements in husked grains from an important riceproducing region in Brazil are presented. Arsenic, Cd, Co, Cu, Fe, Mg, Mn, Ni, Se, and Zn were significantly affected by the microclimatic region and the rice varieties. The only exception observed was the effect of Pb variety selection, with 35.4 % associated with random fluctuations. Varieties with both higher levels of Fe/Zn and lower levels of As/Cd were identified in all regions studied. All regions and varieties were able to produce rice with Cd<10 μg kg−1, but the Santa Vitoria do Palmar region where varieties with Cd<45 μg kg−1 were selected. Well-established varieties result in a higher daily intake of essential elements than the varieties under development. Therefore, our findings may provide information to support the selection procedures for varieties, as well as to encourage improvements in management practices between regions.

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  • IPEN-DOC 27144

    ARAUJO, LEANDRO G. de ; PRADO, EDUARDO S.P. ; MIRANDA, FELIPE de S.; VICENTE, ROBERTO ; SILVA SOBRINHO, ARGEMIRO S. da; PETRACONI FILHO, GILBERTO; MARUMO, JULIO T. . Physicochemical modifications of radioactive oil sludge by ozone treatment. Journal of Environmental Chemical Engineering, v. 8, n. 5, p. 1-8, 2020. DOI: 10.1016/j.jece.2020.104128

    Abstract: An experimental study on the degradation of organic compounds from radioactive oil sludge by the ozonation process is presented. The effects of different concentrations of ozone in the oil sludge degradation over time were investigated. The experiments were performed in a 0.125 L glass reactor with magnetic stirring and a diffuser plate at the bottom to feed the ozone. The ozone concentration varied from 13 to 53 mg L−1 and the total interaction time was 1 h. To investigate the physicochemical properties of the oil sludge (solid and liquid components) prior to and after the treatment, multiple analytical characterization methods were used: Thermal Gravimetric Analysis, X-ray diffraction, Scanning Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy, Fourier Transform Infrared spectroscopy, Spectrophotometer, and Residual Gas Analyzer. The most perceptive change is in the color of the liquid medium turned from dark brown to light yellow, especially under ozone concentrations higher than 33 mg L−1. Absorbance values decreased about 3.5 times after 30 min of treatment with [O3] =53 mg L−1. FTIR spectroscopy showed that the bands associated with the CH3 and CeH in CH2 disappeared during treatment. On the other hand, a greater presence of C]C aromatics was observed. By residual gas analysis, various organic and inorganic gases were identified during the treatment, such as CH4, H2, CO2, and H2S. Finally, the ozonation of the oil sludge proved to be effective, due to its high reaction capacity.

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  • IPEN-DOC 27143

    MATOS, B.R. . The genuine ac-to-dc proton conductivity crossover of nafion and polymer dielectric relaxations as a fuel cell polarization loss. Journal of Electroanalytical Chemistry, v. 871, p. 1-13, 2020. DOI: 10.1016/j.jelechem.2020.114357

    Abstract: The non-ohmic behavior of Nafion electrical properties, i. e., the thickness and potential dependent conductivity, was studied in the impedance, dielectric and conductivity representations with the use of a special through-plane sampleholder in a 4-probe array. Such measurements allowed identifying the genuine ac-to-dc conductivity crossover frequency in Nafion, which occurs for f<10-1 Hz. In addition, the minimization of the interfacial electrode/ionomer polarizations with the 4-probe setup permitted the determination of the bulk dc conductivity and dielectric constant of Nafion, which are σ~0.03 Scm-1 and ε′~106 (T=40 °Cand RH=100%), respectively. The colossal dielectric constant is shown to increase the Debye length of the electric double layer to values comparable to the membrane thickness. Therefore, the exponential increase of the proton conductivity with increasing both membrane thickness and electric potential are a result of canceling out the non-linear effects of electric double layer caused by the high dielectric permittivity of Nafion. The ac-to-dc conductivity crossover in H2/O2 fuel cell impedance curves takes place for f<100 Hz and matches with the ex situ impedance spectroscopy study in excellent agreement, revealing a striking result: the potential dependent conductivity of Nafion requires extra fuel cell overpotential to overcome the electrode/ionomer interfacial polarization representing an additional polarization loss to polymer electrolyte fuel cells.

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  • IPEN-DOC 27142

    SANTOS, M.C.L. ; GODOI, C.M. ; KANG, H.S.; SOUZA, R.F.B. de ; RAMOS, A.S.; ANTOLINI, E.; NETO, A.O. . Effect of Ni content in PdNi/C anode catalysts on power and methanol co-generation in alkaline direct methane fuel cell type. Journal of Colloid and Interface Science, v. 578, p. 390-401, 2020. DOI: 10.1016/j.jcis.2020.06.017

    Abstract: PdNi electrocatalysts supported on carbon were used as anode materials for methane oxidation in alkaline direct methane fuel cells (ADMEFCs). The electrocatalysts were successfully synthesized by the NaBH4 reduction method. X-ray diffraction measurements showed the formation of non-alloyed Pd in the face- centered cubic (FCC) structure for all materials and formation of NiO and Ni(OH)2 species. TEM images showed that the metal particles are well dispersed on the support with small agglomeration regions. Information about the surface structure of the catalyst were obtained by Raman spectra, mainly confirming the presence of Ni(OH)2. The species observed by DEMS, that is, methanol (m/z = 32), CO2 (m/ z = 44) and potassium formate (m/z = 84) were confirmed by FTIR, which also showed the presence of a high amount of carbonate in the methane oxidation products of the ADMEFC with Pd50Ni50/C as the anode catalyst. Tests in ADMEFCs showed that the dependence of the maximum power density on nickel content in the catalysts goes through a maximum value of 13.5 lW cm 2 at 50 at% Ni. Moreover, the amount of produced methanol decreases with increasing Ni content in the PdNi/C catalysts. Both these results can be explained by the enhanced methanol oxidation in the presence of nickel.

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  • IPEN-DOC 27141

    AMARAL, MARCELLO M.; DEL-VALLE, MATHEUS; RAELE, MARCUS P. ; DE PRETTO, LUCAS R. ; ANA, PATRICIA A.. Osteoporosis evaluation through full developed speckle imaging. Journal of Biophotonics, v. 13, n. 7, p. 1-9, 2020. DOI: 10.1002/jbio.202000025

    Abstract: Osteoporosis is a disease characterized by bone mineral density reduction, weakening the bone structure. Its diagnosis is performed using ionizing radiation, increasing health risk. Optical techniques are safer, due to non-ionizing radiation use, but limited to the analyses of bone tissue. This limitation may be circumvented in the oral cavity. In this work we explored the use of laser speckle imaging (LSI) to differentiate the sound and osteoporotic maxilla andmandible bones in an in vitro model. Osteoporosis lesions were simulated with acid attack. The samples were evaluated by optical profilometry and LSI, using a custom software. Two image parameters were evaluated, speckle contrast ration and patches ratio. With the speckle contrast ratio, it was possible to differentiate sound from osteoporotic tissue. From speckle patches ratio it was observed a negative correlation with the roughness parameter. LSI is a promissory technique for assessment of osteoporosis lesions on alveolar bone.

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  • IPEN-DOC 27139

    TORRES, LARISSA H.; REAL, CAROLINE C.; TURATO, WALTER M.; SPELTA, LÍDIA W.; DURÃO, ANA C.C. dos S.; ANDRIOLI, TATIANA C.; POZZO, LORENA ; SQUAIR, PETERSON L. ; PISTIS, MARCO; FARIA, DANIELE de P.; MARCOURAKIS, TANIA. Environmental tobacco smoke during the early postnatal period of mice interferes with brain 18F-FDG uptake from infancy to early adulthood: a longitudinal study. Frontiers in Neuroscience, v. 14, p. 1-11, 2020. DOI: 10.3389/fnins.2020.00005

    Abstract: Exposure to environmental tobacco smoke (ETS) is associated with high morbidity and mortality, mainly in childhood. Our aim was to evaluate the effects of postnatal ETS exposure in the brain 2-deoxy-2-[18F]-fluoro-D-glucose (18F-FDG) uptake of mice by positron emission tomography (PET) neuroimaging in a longitudinal study. C57BL/6J mice were exposed to ETS that was generated from 3R4F cigarettes from postnatal day 3 (P3) to P14. PET analyses were performed in male and female mice during infancy (P15), adolescence (P35), and adulthood (P65). We observed that ETS exposure decreased 18F-FDG uptake in the whole brain, both left and right hemispheres, and frontal cortex in both male and female infant mice, while female infant mice exposed to ETS showed decreased 18F-FDG uptake in the cerebellum. In addition, all mice showed reduced 18F-FDG uptake in infancy, compared to adulthood in all analyzed VOIs. In adulthood, ETS exposure during the early postnatal period decreased brain 18FFDG uptake in adult male mice in the cortex, striatum, hippocampus, cingulate cortex, and thalamus when compared to control group. ETS induced an increase in 18F-FDG uptake in adult female mice when compared to control group in the brainstem and cingulate cortex. Moreover, male ETS-exposed animals showed decreased 18F-FDG uptake when compared to female ETS-exposed in the whole brain, brainstem, cortex, left amygdala, striatum, hippocampus, cingulate cortex, basal forebrain and septum, thalamus, hypothalamus, and midbrain. The present study shows that several brain regions are vulnerable to ETS exposure during the early postnatal period and these effects on 18F-FDG uptake are observed even a long time after the last exposure. This study corroborates our previous findings, strengthening the idea that exposure to tobacco smoke in a critical period interferes with brain development of mice from late infancy to early adulthood.

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  • IPEN-DOC 27138

    OLIVEIRA, J.R.B.; MORALLES, M. ; FLECHAS, D.; CARBONE, D.; CAVALLARO, M.; TORRESI, D.; ACOSTA, L.; AGODI, C.; AMADOR-VALENZUELA, P.; BONANNO, D.; BORELLO-LEWIN, T.; BRISCHETTO, G.A.; CALABRESE, S.; CALVO, D.; CAPIROSSI, V.; CAPPUZZELLO, F.; CHAVEZ-LOMELÍ, E.R.; CIRALDO, I.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FOTI, A.; GALLO, G.; GUAZZELLI, M.A.; HACISALIHOGLU, A.; IAZZI, F.; LINARES, R.; LO PRESTI, D.; MA, J.; MEDINA, N.H.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; REITO, S.; RIES, P.; RUSSO, G.; SGOUROS, O.; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; SPATAFORA, A.; TUDISCO, S.; WANG, J.S.; YANG, Y.Y.; YILDIRIM, A.; ZAGATTO, V.A.B.. First comparison of GEANT4 hadrontherapy physics model with experimental data for a NUMEN project reaction case. European Physical Journal A, v. 56, n. 5, p. 1-9, 2020. DOI: 10.1140/epja/s10050-020-00152-6

    Abstract: Gamma-ray and neutron spectra from the 18O +76Se reaction at 15.3 MeV/u were measured with the EDEN array of liquid scintillators at the LNS. The results were compared to GEANT Hadrontherapy physics list simulations in order to assess the reliability of this model for the development of theNUMENproject.Agood agreement with the shape of the experimental gamma-ray spectra and a reasonable agreement with the total count rates were obtained. The gamma spectra originated from the nuclear reactions were selected by time coincidence with the Superconducting Cyclotron radio-frequency reference signal. The random coincidence background rate was appropriately described only when the Faraday Cup, the material and geometry of the experimental hall and its contents were included in the simulationwith sufficient detail. The information on the radiation spectra is important for the adequate development of the project of the detector arrays and electronic equipment for the advanced phase of NUMEN. Since orders of magnitude larger beam intensities are planned for this phase, the random coincidence rate is also of significant importance, particularly for the performance of the G-NUMEN gamma calorimeter array.

    Palavras-Chave: angular distribution; beam monitoring; coincidence spectrometry; computerized simulation; counting rates; energy spectra; external beam radiation therapy; faraday cups; g codes; gamma radiation; gamma spectra; gamma spectroscopy; mev range 100-1000; neutron spectra; neutrons; oxygen 18 beams; oxygen 18 reactions; selenium 76 target

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  • IPEN-DOC 27135

    LOCOSSELLI, GIULIANO M.; MOREIRA, TIANA C.L.; CHACON-MADRID, KATHERINE; ARRUDA, MARCO A.Z.; CAMARGO, EVELYN P. de; KAMIGAUTI, LEONARDO Y.; TRINDADE, RICARDO I.F. da; ANDRADE, MARIA de F.; ANDRE, CARMEN D.S. de; ANDRE, PAULO A. de; SINGER, JULIO M.; SAIKI, MITIKO ; ZACCARELLI-MARINO, MARIA A.; SALDIVA, PAULO H.N.; BUCKERIDGE, MARCOS S.. Spatial-temporal variability of metal pollution across an industrial district, evidencing the environmental inequality in São Paulo. Environmental Pollution, v. 263, Part A, p. 1-8, 2020. DOI: 10.1016/j.envpol.2020.114583

    Abstract: Although air pollution decreased in some cities that shifted from an industrial to a service-based economy, and vehicular emission regulation became more restrictive, it is still a major risk factor for mortality worldwide. In central S~ao Paulo, Brazil, air quality monitoring stations and tree-ring analyses revealed a decreasing trend in the concentrations of particulate matter and metals. Such trends, however, may not be observed in industrial districts located in the urban periphery, where the usual mobile sources may be combined with local stationary sources. To evaluate environmental pollution in an industrial district in southeastern S~ao Paulo, we assessed its spatial variability, by measuring magnetic properties and concentrations of Al, Ba, Ca, Cl, Cu, Fe, K, Mg, Mn, P, S, Sr, Zn in the bark of 62 trees, and its temporal trends, by measuring Cd, Cu, Ni, Pb, V, Zn in tree rings of three trees. Source apportionment analysis based on tree barks revealed two clusters with high concentrations of metals, one related to vehicular and industrial emissions (Al, Ba, Cu, Fe, Zn) in the east side of the industrial cluster, and the other related to soil resuspension (Cu, Zn, Mn) in its west side. These patterns are also supported by the magnetic properties of bark associated with iron oxides and titanium-iron alloy concentrations. Dendrochemical analyses revealed that only the concentrations of Pb consistently decreased over the last four decades. The concentrations of Cd, Cu, Ni, V, and Zn did not significantly decrease over time, in contrast with their negative trends previously reported in central S~ao Paulo. This combined biomonitoring approach revealed spatial clusters of metal concentration in the vicinity of this industrial cluster and showed that the local population has not benefited from the decreasing polluting metal concentrations in the last decades.

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  • IPEN-DOC 27134

    PELEGRINO, MILENA T.; KOHATSU, MARCIO Y.; SEABRA, AMEDEA B.; MONTEIRO, LUCILENA R. ; GOMES, DIEGO G.; OLIVEIRA, HALLEY C.; ROLIM, WALLACE R.; JESUS, TATIANE A. de; BATISTA, BRUNO L.; LANGE, CAMILA N.. Effects of copper oxide nanoparticles on growth of lettuce (Lactuca sativa L.) seedlings and possible implications of nitric oxide in their antioxidative defense. Environmental Monitoring and Assessment, v. 192, n. 4, p. 1-14, 2020. DOI: 10.1007/s10661-020-8188-3

    Abstract: Copper oxide nanoparticles (CuO NPs) have been extensively explored for use in agriculture. Previous studies have indicated that application of CuO NPs might be promising for development and conservation of plants, pest control, and for the recovery of degraded soils. However, depending on the applied concentration copper can cause phytotoxic effects. In this work, biosynthesized CuO NPs (using green tea extract) were evaluated on their effects on lettuce (Lactuca sativa L.) seedling growth, which were exposed at concentrations ranged between 0.2 and 300 μg mL−1. From the biosynthesized were obtained ultra-small CuO NPs (~ 6.6 nm), with high stability in aqueous suspension. Toxicity bioassays have shown that at low concentrations (up to 40 μg mL−1), CuO NPs did not affect or even enhanced the seed germination. At higher concentrations (higher than 40 μg mL−1), inhibition of seed germination and radicle growth ranging from 35 to 75% was observed. With the increase of CuO NPs concentrations, nitrite and S-nitrosothiols levels in radicles increased, whereas superoxide dismutase and total antioxidant activities decreased. The nitrite and Snitrosothiols levels in lettuce radicles showed a direct dose response to CuO NP application, which may indicate nitric oxide-dependent signaling pathways in the plant responses. Therefore, the results demonstrated that at low concentrations (≤ 20 μg mL−1) of CuO NPs, beneficial effects are obtained from seedlings, enhancing plant growth, and the involvement of nitric oxide signaling in the phytotoxic effects induced by high concentration of this formulation.

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  • IPEN-DOC 27133

    COUTO, CAMILA P. ; REVILLA, REYNIER I.; COLOSIO, MARCO A.; COSTA, ISOLDA ; PANOSSIAN, ZEHBOUR; DE GRAEVE, IRIS; TERRYN, HERMAN; ROSSI, JESUALDO L. . Electrochemical behaviour of 22MnB5 steel coated with hot-dip Al-Si before and after hot-stamping process investigated by means of scanning Kelvin probe microscopy. Corrosion Science, v. 174, p. 1-10, 2020. DOI: 10.1016/j.corsci.2020.108811

    Abstract: Press-hardened steels are commonly protected with hot-dip Al-Si coating. Due to the electrochemical complexity of this system, either before or after hot-stamping process, SKPFM was used to investigate the influence of the thermo-mechanical process on the electrochemical behaviour of the galvanic coupling. The hot-stamping process changed significantly the anodic/cathodic coupling of the coating/steel due to iron enrichment in the coating layer. Hence, a concurrent mechanism was thoroughly established, i.e., while the press hardening enhances the corrosion properties of the steel system (steel and metallic coating) through diffusion, at the same time it diminishes the cathodic protection of the Al-Si layer.

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  • IPEN-DOC 27132

    COELHO, EDNEI; REIS, TATIANA A.; COTRIM, MARYCEL ; MULLAN, THOMAS K.; CORREA, BENEDITO. Resistant fungi isolated from contaminated uranium mine in Brazil shows a high capacity to uptake uranium from water. Chemosphere, v. 248, p. 1-9, 2020. DOI: 10.1016/j.chemosphere.2020.126068

    Abstract: The Osamu Utsumi uranium mine occupies a 20 km2 area in the city of Caldas, which is located in the state of Minas Gerais, Brazil. Since mining activities ended at Osamu Utsumi 24 years ago, the surrounding area has become contaminated by acid effluents containing high concentrations of uranium. Thus, the aim of this study was to assess the uranium bioremediation capacity of 57 fungi isolated from the mine area. In tolerance tests, 38% (22) of the fungal isolates were considered tolerant to uranium, including 10 Penicillium species. At a uranium concentration of 2000 mg L 1 48 fungi did not exhibit mycelial growth index inhibition. Minimal inhibitory concentration (MIC) analysis showed growth of 25 fungi above a uranium concentration of 8000 mg L 1. At high uranium concentrations, some fungi (i.e., Talaromyces amestolkiae and Penicillium citrinum) showed morphological changes and pigment (melanin) production. Among the fungal isolates, those considered to be more tolerant to uranium were isolated from soil and sediment samples containing higher concentrations of heavy metal. When comparing the results of resistance/tolerance tests with those for uranium biosorption capacity, we concluded that the fungi isolated from the Osamu Utsumi mine with the best potential for uranium bioremediation were Gongronella butleri, Penicillium piscarium, Penicillium citrinum, Penicillium ludwigii, and Talaromyces amestolkiae. Biosorption tests with live fungal biomass showed that 11 species had a high potential for uranium uptake from contaminated water.

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  • IPEN-DOC 27131

    DUARTE, LUIS F. de A.; BLASCO, JULIAN; CATHARINO, MARILIA G.M. ; MOREIRA, EDSON G. ; TROMBINI, CHIARA; NOBRE, CAIO R.; MORENO, BEATRIZ B.; ABESSA, DENIS M. de S.; PEREIRA, CAMILO D.S.. Lead toxicity on a sentinel species subpopulation inhabiting mangroves with different status conservation. Chemosphere, v. 251, p. 1-13, 2020. DOI: 10.1016/j.chemosphere.2020.126394

    Abstract: Lead is a priority pollutant introduced in the aquatic environment by different sources commonly located in estuarine regions, such as ports, marinas and industries. Environmental agencies around the world set the maximum allowable concentration of lead in effluents, surface water and sediment, but few studies reported its accumulation and chronic toxicity in mangrove benthic invertebrates using concentrations believed to be safe. In the case of Brazilian mangrove environments, Ucides cordatus is a crab species of choice to be used in bioaccumulation studies. We have assessed biomarkers’ responses (DNA strand breaks, micronucleated cells, metallothioneins, enzymatic activity of aminolevulinic acid dehydratase and neutral red retention time) and the total bioaccumulation in six tissues of U. cordatus crabs resident to mangrove areas under different conservation status during a 28-day period bioassay. We also investigated Pb subcellular partition and biomarkers’ responses using a supposedly safe concentration (10 mg L 1). During the Pb exposure, the highest concentration of Pb was observed in crab gills. Crabs also showed a high ability to allocate Pb in detoxified forms. Multivariate analysis pointed out that bioaccumulation (total, active and detoxified) is linked to biomarkers. Even in supposedly safe dosage, U. cordatus triggered its defense mechanisms expressing more metallothioneins and presented relevant cyto-genotoxic damage. Our data suggest the development of biological tolerance to Pb in crabs from polluted areas. Our results provided a new insight about lead toxicity even at concentrations considered environmentally safe, which could support new strategies to manage estuarine areas considering their respective conservation status.

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  • IPEN-DOC 27130

    RICHARD, DIEGO; RENTERÍA, MARIO; CARBONARI, ARTUR W. ; ROMERO, MARIANO; FACCIO, RICARDO. Preparation of In-doped Y2O3 ceramics through a sol-gel process: effects on the structural and electronic properties. Ceramics International, v. 46, n. 10, p. 16088-16095, 2020. DOI: 10.1016/j.ceramint.2020.03.161

    Abstract: The Pechini-type sol-gel (PSG) process has been used for the preparation of doped oxides due to its capability to overcome most of the difficulties that frequently occur by using other producing methods. In this work we analyze the case of samples of pure and In-doped yttria (Y2O3) prepared by the PSG process. We experimentally characterize the synthesized samples by x-ray diffraction, micro-Raman spectroscopy, electrochemical impedance spectroscopy (EIS), and time-differential perturbed γ-γ angular correlation (PAC) spectroscopy, and we compare these results with those obtained starting from commercial oxide powders. We found that the PSG process can be used to successfully produce doped yttria in the cubic phase, with the impurities substitutionally located at the cationic sites of the structure. By the proposed PSG route, the inclusion of impurities does not affect the particle size nor the resistivity. However, when we compare the PSG samples with other samples produced from commercial powder, we found that the first have lower resistivities at grain interiors. On the other hand, PAC spectroscopy in 111In(→111Cd)-doped yttria allows the study of the dynamic hyperfine interactions observed by the radioactive 111Cd impurity-probe, which can be used to “sense” the host electron availability near the impurities after the electron-capture decay of 111In. Differences between PAC spectra for PSG samples and the commercial powder suggest that the PSG process introduces additional donor defects into the yttria electronic structure, which is consistent with the lower resistivity observed in the PSG samples by EIS spectroscopy.

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  • IPEN-DOC 27129

    BERTOLETE, M.; BARBOSA, P.A. ; ROSSI, WAGNER de ; FREDERICCI, C.; MACHADO, I.F.. Mechanical characterisation and machining evaluation of ceramic cutting tools functionally graded with six layers. Ceramics International, v. 46, n. 10, p. 15137-15145, 2020. DOI: 10.1016/j.ceramint.2020.03.048

    Abstract: Functionally graded materials (FGMs) are composites graded in one or more directions by the mean volume fraction variation of their constituents in a continuous or stepwise design. The objective of this study is to apply the FGM concept to ceramic cutting tools to widen its application range. Thus, two cutting tool materials were selected: cemented carbide, owing to its higher toughness, and alumina-based ceramic, owing to its high wear resistance at elevated temperatures. Ceramics based on alumina were functionally graded with cemented carbide and sintered using the spark plasma sintering technique. The thermal residual stresses were predicted; additionally, the microstructure, relative density, and Vickers hardness and fracture toughness for the alumina layer were evaluated, and flexural strength and machining tests were conducted. From the results, cracks were not observed in the microstructure and full density was obtained. In general, the hardness and fracture toughness values were close to those in the literature. A flexural strength improvement of at least 50% on FGM samples was observed in comparison to homogeneous ceramic ones. The FGM cutting tools supported approximately 1000 N of machining force without catastrophic failure when turning martensitic stainless steel into a conventional lathe. The values of surface roughness (Ra and Rz) agree with those in the literature under similar cutting and geometry conditions.

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  • IPEN-DOC 27128

    VIEIRA, LAÍS H.S.; SABINO, CARLA M.S.; SOARES JÚNIOR, FRANCISCO H.; ROCHA, JANAINA S.; CASTRO, MANUELA O.; ALENCAR, RAFAEL S.; COSTA, LUELC S. da; VIANA, BARTOLOMEU C.; PAULA, AMAURI J. de; SOARES, JOAO M.; SOUZA FILHO, ANTONIO G.; OTUBO, LARISSA ; FECHINE, PIERRE B.A.; GHOSH, ANUPAMA; FERREIRA, ODAIR P.. Strategic design of magnetic carbonaceous nanocomposites and its application as multifunctional adsorbent. Carbon, v. 161, p. 758-771, 2020. DOI: 10.1016/j.carbon.2020.01.089

    Abstract: Magnetic carbonaceous nanocomposites (MCN) were prepared by hydrothermal carbonization (HTC) of a carbohydrate in the presence of Fe3þ, followed by thermal treatment with KOH for simultaneous activation and magnetization. The precursor formed (IOCN) in the HTC process contained iron oxide nanoparticles encapsulated in the hydrochar matrix. The thermochemical parameters of the activation (temperature and IOCN/KOH mass-ratio) were varied to achieve an increase of the specific surface area along with formation of magnetic phases in MCN compared to IOCN. Activation temperature was found to be responsible for the structural and morphological properties of the MCNs whereas the IOCN/KOH mass-ratio controlled the porosity. The magnetic properties of the MCNs originated from the formation of Fe3O4 and Fe0 phases, which are encapsulated in the carbonaceous material. The MCNs were tested for adsorption of methylene blue (MB) dye, followed by magnetic separation. The MCN, produced in the optimized conditions, showed a specific surface area of 766 m2 g 1, magnetization of 8 emu g 1 and a MB adsorption capacity of 570 mg g 1. Detailed kinetic and isotherm studies of MB adsorption were also performed. The methodology of simultaneous activation and magnetization to generate MCNs, presented here, could be extended to obtain new multifunctional carbon-based nanocomposite adsorbent starting from different biomasses.

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  • IPEN-DOC 27127

    BORDON, ISABELLA C.; JOVIANO, WILLIAN R.; MEDEIROS, ALINE M.Z. de; CAMPOS, BRUNO G. de; ARAUJO, GIULIANA S. de; GUSSO-CHOUERI, PALOMA K.; PRETO, MAYRA de F.; FAVARO, DEBORAH I.T. ; ABESSA, DENIS M. de S.. Heavy metals in tissues of blue crabs Callinectes danae from a subtropical protected estuary influenced by mining residues. Bulletin of Environmental Contamination and Toxicology, v. 104, n. 4, p. 418-422, 2020. DOI: 10.1007/s00128-020-02815-y

    Abstract: This short note aims to report in detail a preliminary assessment of the concentrations of Cd, Hg and Pb in tissues of blue crabs Callinectes danae collected from the Cananéia-Iguape-Peruíbe estuarine complex (CIP), in the South of São Paulo State coast, Brazil. In October 2014, blue crabs were collected from CIP. Tissues were removed by dissection and metal determination was performed by GF-AAS and CV-AAS. According to statistical analysis, Pb and Cd concentrations in gills were significantly higher than those found in muscles and hepatopancreas, respectively. There were no significant differences in Hg concentrations between samples. Cd, Hg and Pb concentrations in gills and hepatopancreas were lower than those reported in a previous study performed at CIP. However, Cd concentration in hepatopancreas was higher than the Brazilian limit for consumption and new efforts to monitor Cd concentrations in C. danae tissues must be performed.

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  • IPEN-DOC 27126

    DALTOE, FELIPE P.; OLIVEIRA, NÉLIO A.J. de ; PERONI, CIBELE N. ; SHARPE, PAUL T.; MANTESSO, ANDREA. Phenotype changes of oral epithelial stem cells after in vitro culture. Brazilian Oral Research, v. 34, p. 1-8, 2020. DOI: 10.1590/1807-3107bor-2020.vol34.0033

    Abstract: The aim of our study was to isolate populations of keratinocyte stem cells based on the expression of cell surface markers and to investigate whether the culture could affect their phenotype. keratinocytes from human oral mucosa were sorted based on the expression of the epithelial stem cell markers p75NTR and CD71. We also examined the co-expression of other epithelial stem markers such as integrins β1 and α6 and their stem cell-like proprieties in in vitro assays. Three passages after being sorted by MACS, more than 93% of the p75NTR+ve cells lost the expression of p75NTR, while 5.46% of the p75NTR-ve gained it. Within the small population of the p75NTR+ve cells, 88% co-expressed other epithelial stem cell markers such as integrins β1 and α6, while only 28% of p75NTR-ve cells co-expressed these markers. These results were confirmed by sorting cells by FACS. Additionally, when double staining was used for sorting cells, 99% of the p75NTR+veCD71-ve and 33% of the p75NTR-veCD71+ve cells expressed both integrins, but just one week after culture, only 1.74% of the p75NTR+veCD71-ve cells still expressed p75NTR and only 0.32% still expressed CD71. Similar results were obtained when co-culturing p75NTR+ve and p75NTR-ve populations before analysis. Our results suggest that phenotype changes may be part of an intrinsic cellular mechanism to conserve levels of protein expression as they may found in the human body. In addition, in vitro culture may not offer ideal conditions for epithelial stem cell maintenance due to phenotype changes under standard culture conditions.

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  • IPEN-DOC 27125

    BELLEZZO, MURILLO ; FONSECA, GABRIEL P.; VONCKEN, ROBERT; VERRIJSSEN, AN-SOFIE; VAN BEVEREN, CELINE; ROELOFS, ERIK; YORIYAZ, HELIO ; RENIERS, BRIGITTE; VAN LIMBERGEN, EVERT J.; BERB EE, MAAIKE; VERHAEGEN, FRANK. Advanced design, simulation, and dosimetry of a novel rectal applicator for contact brachytherapy with a conventional HDR 192Ir source. Brachytherapy, v. 19, n. 4, p. 544-553, 2020. DOI: 10.1016/j.brachy.2020.03.009

    Abstract: PURPOSE: Dose escalation yields higher complete response to rectal tumors, which may enable the omission of surgery. Dose escalation using 50 kVp contact x-ray brachytherapy (CXB) allow the treatment of a selective volume, resulting in low toxicity and organs-at-risk preservation. However, the use of CXB devices is limited because of its high cost and lack of treatment planning tools. Hence, the MAASTRO applicator (for HDR 192Ir sources) was developed and characterized by measurements and Monte Carlo simulations to be a cost-effective alternative to CXB devices. METHODS AND MATERIALS: A cylindrical applicator with lateral shielding was designed to be used with a rectoscope using its tip as treatment surface. Both the applicator and the rectoscope have a slanted edge to potentially allow easier placement against tumors. The applicator design was achieved by Monte Carlo modeling and validated experimentally with film dosimetry, using the Papillon 50 (P50) device as reference. RESULTS: The applicator delivers CXB doses in less than 9 min using a 20375 U source for a treatment area of approximately 20 20 mm2 at 2 mm depth. Normalized at 2 mm, the dose falloff for depths of 0 mm, 5 mm, and 10 mm are 130%, 70%, and 43% for the P50 and 140%, 67%, and 38% for the MAASTRO applicator, respectively. CONCLUSIONS: The MAASTRO applicator was designed to use HDR 192Ir sources to deliver a dose distribution similar to those of CXB devices. The applicator may provide a cost-effective solution for endoluminal boosting with clinical treatment planning system integration.

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  • IPEN-DOC 27124

    COURROL, LILIA C.; ESPINOZA-CULUPÚ, ABRAHAM; SILVA JUNIOR, PEDRO I. da; GONÇALVES, KARINA de O.; SILVA, FLAVIA R. de O. ; BORGES, MONAMARIS M.. Antibacterial and antitumoral activities of the spider acylpolyamine Mygalin silver nanoparticles. BioNanoScience, v. 10, n. 2, p. 463-472, 2020. DOI: 10.1007/s12668-020-00738-w

    Abstract: Mygalin is a synthetic analog of polyamine spermidine isolated from spider hemocytes. Polyamines show potential therapeutic activity against a wide range of human diseases such as cancer and microbial infections. In this work, we analyzed the antibacterial and antitumoral activities of Mygalin silver nanoparticles synthesized by the photoreduction method. The formation and distribution of MygAgNPs were confirmed by UV-visible spectroscopy, zeta potential, and transmission electron microscopy. The obtained nanoparticles were mostly spherical with a particle size distribution in the range of ~ 10–60 nm. We have demonstrated that MygAgNPs increased the effectiveness of the native Mygalin by approximately 6400-fold. Cytotoxicity tests were performed, and it was possible to reach a concentration that was not toxic to healthy cells (NHI-3T3) and at the same time toxic to the tumor cell line (MCF-7). The obtained results suggest that this system shows potential enhanced antibacterial activity against Escherichia coli, DH5α and anticancer activity against MCF-7 cell line.

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  • IPEN-DOC 27123

    MOREIRA, GREGORI de A. ; GUERRERO-RASCADO, JUAN L.; BRAVO-ARANDA, JUAN A.; FOYO-MORENO, INMACULADA; CAZORLA, ALBERTO; ALADOS, INMACULADA; LYAMANI, HASSAN; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS. Study of the planetary boundary layer height in an urban environment using a combination of microwave radiometer and ceilometer. Atmospheric Research, v. 240, p. 1-15, 2020. DOI: 10.1016/j.atmosres.2020.104932

    Abstract: The Planetary Boundary Layer (PBL) is an important part of the atmosphere that is relevant in different atmospheric fields like pollutant dispersion, and weather forecasting. In this study, we analyze four and five-year datasets of measurements gathered with a ceilometer and a microwave radiometer to study the PBL structure respectively, in the mid-latitude urban area of Granada (Spain). The methodologies applied for the PBL Height (PBLH) detection (gradient method for ceilometer and the combination of parcel method and temperature gradient method for microwave radiometer) provided a description in agreement with the literature about the PBL structure under simple scenarios. Then, the PBLH behavior is characterized by a statistical study of the convective and stable situations, so that the PBLH was obtained from microwave radiometer measurements. The analysis of the PBLH statistical study shows some agreement with other PBLH studies such as daily pattern and yearly cycle, and the discrepancies were explained in terms of distinct latitudes, topography and climate conditions. Finally, it was performed a joint long-term analysis of the residual layer (RL) provided by ceilometer and the stable and convective layer heights determined by microwave radiometer, offering a complete picture of the PBL evolution by synergetic combination of remote sensing techniques. The PBL behavior has been used for explaining the daily cycle of Black Carbon (BC) concentration, used as tracer of the pollutants emissions associated to traffic.

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  • IPEN-DOC 27122

    DAFRÉ-MARTINELLI, MARCELLE; FIGUEIREDO, ANA M.G. ; DOMINGOS, MARISA. Trace element leaf accumulation in native trees from the remaining Semideciduous Atlantic Forest in Brazil. Atmospheric Pollution Research, v. 11, n. 5, p. 871-879, 2020. DOI: 10.1016/j.apr.2020.01.015

    Abstract: Remnants of Semideciduous Atlantic Forest surrounded by numerous industries, intense road traffic and agricultural lands in Southeast Brazil have been affected by trace elements. We implemented a passive biomonitoring with the three most abundant native tree species (Astronium graveolens, Croton floribundus and Piptadenia gonoacantha) to answer these questions: 1) which species has the greatest potential to accumulate trace elements?; 2) does the leaf accumulation level of trace elements vary between the edge and interior of the forest remnants, between dry and wet periods or due to the distance from the industrial area?; 3) which species, among the most abundant in the forest remnants, would better indicate the spatial variations in trace elements pollution and which elements would be the most relevant for such spatial discrimination? Leaf samples were collected during the dry and wet seasons, at the edge and interior of four forest remnants. Trace elements were determined using inductively coupled plasma mass spectrometry (ICP MS). Few edge effects were evidenced in the leaf concentrations in all species. Higher concentrations of most trace elements were measured during dry season. Although C. floribundus showed the most accumulating capacity, A. graveolens was the most appropriate species to discriminate spatial variations. The forest closer to the industrial area was distinguished from the others by Mn and Ni from oil burning, but the metal pollution from the industrial area did not interfere on the leaf concentrations in A. graveolens sampled in the urban and rural forests.

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  • IPEN-DOC 27121

    ARAUJO, G.S.; GUSSO-CHOUERI, P.K.; FAVARO, D.I.T. ; ROCHA, R.C.C.; SAINT'PIERRE, T.D.; HAUSER-DAVIS, R.A.; BRAZ, B.; SANTELLI, R.E.; FREIRE, A.S.; MACHADO, W.T.V.; CRUZ, A.C.F.; ABESSA, D.M.S.. Metal‑associated biomarker responses in crabs from a marine protected area in Southeastern Brazil. Archives of Environmental Contamination and Toxicology, v. 78, n. 3, p. 463-477, 2020. DOI: 10.1007/s00244-020-00710-5

    Abstract: The environmental quality of a Ramsar wetland site located at the Cananéia-Iguape-Peruíbe Protected Area (CIP-PA), in São Paulo, Brazil, was assessed by geochemical analyses and biomarker assessments (GPx, GST, GSH, GST, MT, LPO, DNA damage) performed in swimming crab Callinectes danae Smith, 1869 organs (posterior and anterior gills and hepatopancreas) to estimate sediment contaminant bioavailability. The results indicated that two sampling stations, PT and PM, exhibited the worst environmental conditions, as sediments collected at both points contained metal contamination, while crabs exhibited significant responses for GPx, GST, and LPO (mostly during winter). Sediment contamination tended to be associated to fine sediments (both seasons) and organic matter (winter). During the summer survey, Pb concentrations in sediments of station PT exceeded the Brazilian Sediment Quality Guidelines (SQGs) and the Canadian Interim Marine Sediment Quality Guidelines. Metal concentrations in sediments sampled in winter were higher compared with summer, with Co, Ni, and Pb exceeding SQGs levels at PT, whereas Co, Ni, Hg, Zn, and Pb exceeded SQGs at PM. Biomarker induction during summer appeared to be caused by natural variables (water salinity and temperature, and molting cycle), whereas oxidative stress and tissue damage during winter appeared to be more clearly linked to metal contamination. Anterior gills presented the clearest signs of seasonal variability, being more responsive to sediment contamination. The results suggest that metals originated from the upper Ribeira de Iguape River are transported toward the estuarine system, causing effects on C. danae individuals. Additionally, seasonality is a strong factor concerning CIP-PA toxicity, since the rainfall regime significantly modifies the freshwater flow and, consequently, estuarine water salinity, suspended particle and metal inputs, as well as the location of depositional areas. Thus, efforts to mitigate CIP-PA contamination should be based on the control of upstream pollution sources.

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  • IPEN-DOC 27120

    CASTRO, PEDRO A.A. ; LIMA, CASSIO A. ; MORAIS, MYCHEL R.P.T.; ZORN, TELMA M.T.; ZEZELL, DENISE M. . Monitoring the progress and healing status of burn wounds using infrared spectroscopy. Applied Spectroscopy, v. 74, n. 7, p. 758-766, 2020. DOI: 10.1177/0003702820919446

    Abstract: Burns are one of the leading causes of morbidity worldwide and the most costly traumatic injuries. A better understanding of the molecular mechanisms in wound healing is required to accelerate tissue recovery and reduce the health economic impact. However, the standard techniques used to evaluate the biological events associated to wound repair are laborious, time-consuming, and/or require multiple assays/staining. Therefore, this study aims to evaluate the feasibility of Fourier transform infrared (FT-IR) spectroscopy to monitor the progress and healing status of burn wounds. Burn injuries were induced on Wistar rats by water vapor exposure and biopsied for further histopathological and spectroscopic evaluation at four time-points (3, 7, 14, and 21 days). Spectral data were preprocessed and compared by principal component analysis. Pairwise comparison of post-burn groups to each other revealed that metabolic activity induced by thermal injury decreases as the healing progresses. Higher amounts of carbohydrates, proteins, lipids, and nucleic acids were evidenced on days 3 and 7 compared to healthy skin and reduced amounts of these molecular structural units on days 14 and 21 postburn. FT-IR spectroscopy was used to determine the healing status of a wound based on the biochemical information retained by spectral signatures in each phase of healing. Our findings demonstrate that FT-IR spectroscopy can monitor the biological events triggered by burn trauma as well as to detect the wound status including full recovery based on the spectral changes associated to the biochemical events in each phase.

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  • IPEN-DOC 27119

    SILVA JÚNIOR, IREMAR A. da ; SIQUEIRA, PAULO de T.D. ; NASCIMENTO, EDUARDO do; YORIYAZ, HELIO ; SORDI, GIAN-MARIA A.A. ; POTIENS, MARIA da P.A. . Variability: surface intensity distribution of large-area reference sources. Applied Radiation and Isotopes, v. 160, p. 1-7, 2020. DOI: 10.1016/j.apradiso.2020.109108

    Abstract: In this paper we present the impact of variability, a surface source parameter, on the efficiency evaluation of surface contamination monitors. This study was based on two source uniformity correction methodologies and data from real surface source distributions. Surface source intensity distribution has been changed by rearranging the cells (portions of the active area of each LARS) while keeping the same source uniformity value. Instrument efficiencies have been calculated for different sets of uniformities and variabilities. This study led to emphasize the importance of variability, a differential source intensity distribution parameter, over the uniformity, an integral source intensity distribution parameter, and reinforced the importance of the source uniformity correction procedure on the course of surface contamination monitor calibration.

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  • IPEN-DOC 27118

    YAMAZAKI, I.M. ; KOSKINAS, M.F. ; MOREIRA, D.S. ; SEMMLER, R. ; BRANCACCIO, F. ; DIAS, M.S. . Primary standardization and determination of gamma ray emission intensities of Ho-166. Applied Radiation and Isotopes, v. 164, p. 1-6, 2020. DOI: 10.1016/j.apradiso.2020.109237

    Abstract: The procedure followed by the Nuclear Metrology Laboratory (LMN) at the IPEN-CNEN/SP, in S~ao Paulo, for the primary standardization of 166Ho is described. The activity of 166Ho was determined by the efficiency extrapolation technique applied to a 4πβ(PC)-γ coincidence system using a gas flow proportional counter in 4π geometry coupled to a 76 x 76 mm NaI(Tl) crystal. The results for the γ-rays intensities at 80.57 and 1379.45 keV were 0.0651(11) and 0.00904(11), respectively.

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  • IPEN-DOC 27117

    SILVA JÚNIOR, IREMAR A. ; SIQUEIRA, PAULO de T.D. ; NASCIMENTO, EDUARDO do; YORIYAZ, HELIO ; SORDI, GIAN-MARIA A.A. ; VIVOLO, VITOR ; POTIENS, MARIA da P.A. . Correction factors for non-uniform large-area reference sources. Applied Radiation and Isotopes, v. 160, p. 1-6, 2020. DOI: 10.1016/j.apradiso.2020.109082

    Abstract: Based on uniformity measurements of large-area reference sources used in calibration procedures of surface contamination monitors, an investigation was carried out to obtain a method that estimates the bias originated from surface source intensity distribution deviation from the ideal uniform distribution and corrects it. It relies on correcting the estimated instrument efficiency by applying correction factors driven from the uniformity distribution profiles of the sources used in calibration procedure. Simulations of the monitor calibration procedure are run for 2 distinct surface source distributions: the real and the ideally uniform distributions. Correction factors are driven from counting rate estimates obtained from each source representation. In order to evaluate adequacy of this proposition it was validated against a method proposed by the NPL in the Good Practices Guide No.14.

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  • IPEN-DOC 27116

    LECONTE, P.; ARCHIER, P.; DE SAINT JEAN, C.; DINIZ, R. ; SANTOS, ADIMIR dos ; FAUTRAT, L.; FOLIGNO, D.; GESLOT, B.; GILAD, E.; TAMAGNO, P.; TRUCHET, G.; ZOIA, A.. New delayed neutron group constants and covariances for LWR core applications, combining summation calculations and integral experiments. Annals of Nuclear Energy, v. 139, p. 1-9, 2020. DOI: 10.1016/j.anucene.2019.107250

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  • IPEN-DOC 27115

    CAVALLARO, MANUELA; ACOSTA, LUIS; AGODI, CLEMENTINA; ALTANA, CARMEN; AMADOR-VALENZUELA, PAULINA; AUERBACH, NAFTALI; BAREA, JOSE; BELLONE, JESSICA I.; BIJKER, ROELOF; BONANNO, DANILO; BORELLO-LEWIN, THEREZA; BOZTOSUN, ISMAIL; BRANCHINA, VINCENZO; BRASOLIN, SANDRO; BRISCHETTO, GIUSEPPE A.; BRUNASSO, OSCAR; BURRELLO, STEFANO; CALABRESE, SALVATORE; CALABRETTA, LUCIANO; CALVO, DANIELA; CAPIROSSI, VITTORIA; CAPPUZZELLO, FRANCESCO; CARBONE, DIANA; CHARON GARCIA, LUIS E.; CHÁVEZ LOMELI, EFRAIN R.; CHEN, RUOFU; CIRALDO, IRENE; COLONNA, MARIA; D'AGOSTINO, GRAZIA; DELAUNAY, FRANCK; DESHMUKH, NIKIT; DJAPO, HARIS; DE GERONIMO, GIANLUIGI; DE LOS RÌOS, K.; FERRARESI, CARLO; FERREIRA, JONAS L.; FERRETTI, JACOPO; FINOCCHIARO, PAOLO; FIRAT, SUNA; FISICHELLA, MARIA; FOTI, ANTONINO; GALLO, GIUSEPPE; GARCIA-TECOCOATZI, HUGO; HACISALIHOGLU, AYLIN; HUERTA-HERNANDEZ, ARCADIO; KOTILA, JENNI; KUCUK, YASEMIN; IAZZI, FELICE; LANZALONE, GAETANO; LAY, JOSÉ A.; LA FAUCI, LAURA; LA VIA, FRANCESCO; LENSKE, HORST; LINARES, ROBERTO; LO PRESTI, DOMENICO; LUBIAN, JESUS; MA, JUNBING; MARIN-LÁMBARRI, DANIEL; MAS RUIZ, J.; MEDINA, NILBERTO H.; MENDES, DJALMA R.; MEREU, PAOLO; MORALLES, MAURICIO ; NERI, LORENZO; OLIVEIRA, JOSÉ R.B.; PAKOU, ATHENA; PANDOLA, LUCIANO; PETRASCU, HORIA; PIETRALLA, NORBERT; PINNA, FEDERICO; REITO, SANTO; RIES, PHILIPP C.; RODRIGUES, MARCIA R.D.; RUSSO, ANTONIO D.; RUSSO, GIUSEPPE; SANTOPINTO, ELENA; SANTOS, ROBERTO B.B.; SERBINA, LEONARDO; SGOUROS, ONOUFRIOS; SILVEIRA, MARCILEI A.G. da; SOLAKCI, SELÇUK O.; SOULIOTIS, GEORGE; SOUKERAS, VASILEIOS; SPATAFORA, ALESSANDRO; TORRESI, DOMENICO; TUDISCO, SALVATORE; VARGAS HERNANDEZ, HESIQUIO; VSEVOLODOVNA, RUSLAN I.M.; WANG, JAN S.; WERNER, VOLKER; YANG, YAN Y.; YILDIRIN, AYDIN; ZAGATTO, VINICIUS A.B.. Recent results on heavy-ion induced reactions of interest for neutrinoless double beta decay at INFN-LNS. EPJ Web of Conferences, v. 223, n. 01009, p. 1-5, 2019. DOI: 10.1051/epjconf/201922301009

    Abstract: The possibility to use a special class of heavy-ion induced direct reactions, such as double charge exchange reactions, is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay half-life. The methodology of the experimental campaign presently running at INFN - Laboratori Nazionali del Sud is reported and the experimental challenges characterizing such activity are described.

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  • IPEN-DOC 27114

    COUTO, CAMILA P. ; COSTA, ISOLDA ; VIVEIROS, BARBARA V.G. de ; ALENCAR, MAICON C. de ; COLOSIO, MARCO A.; PANOSSIAN, ZEHBOUR; ROSSI, JESUALDO L. . The use of scanning vibrating electrode technique to evaluate the effect of hot stamping on the corrosion resistance of 22MnB5 press-hardened steel electroplated with Zn-Ni. Materials Research, v. 22, suppl. 1, p. 1-6, 2019. DOI: 10.1590/1980-5373-MR-2019-0163

    Abstract: Carmakers must achieve the worldwide targets for lightweight materials, safety and reducing the fuel consumption. The use of press-hardened steel (PHS), in vehicle structures has been contributing with these requirements. This type of steel is widely used for the hot-stamping which consists in heating the steel blank to total austenitization temperature and then transferring it from the furnace into the die tool where the steel is formed and quenched at the same time. PHS is usually protect with metallic coatings in order to avoid both steel oxidation and decarburization. Hot-dip Al-Si coating is currently the main used in this application. However, alternative coatings, like zinc-based, are under investigation. This work aims at evaluating the corrosion resistance of the 22MnB5 grade PHS, electroplated with Zn-Ni, before and after hot stamping, using the scanning vibrating electrode technique (SVET). Results from SVET showed that samples prior to hot stamping, the corrosion mechanism was uniform over the exposed surface, and was mainly related to selective dissolution of zinc from the coating. On the other hand, hot stamped samples showed localized corrosion mechanism with decrease in current with time of immersion due to the formation of corrosion products on the exposed surface.

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  • IPEN-DOC 27113

    MUNAWAR, AISHA; AKREM, AHMED; HUSSAIN, ASHIQ; SPENCER, PATRICK ; BETZEL, CHRISTIAN. Molecular model of cytotoxin-1 from Naja mossambica mossambica venom in complex with chymotrypsin. Theoretical Biology Forum, v. 108, n. 1-2, p. 89-99, 2015. DOI: 10.1400/240197

    Abstract: Snake venom is a myriad of biologically active proteins and peptides. Three finger toxins are highly conserved in their molecular structure, but interestingly possess diverse biological functions. During the course of evolution the introduction of subtle mutations in loop regions and slight variations in the three dimensional structure, has resulted in their functional versatility. Cytotoxin-1 (UniProt ID: P01467), isolated from Naja mossambica mossambica, showed the potential to inhibit chymotrypsin and the chymotryptic activity of the 20S proteasome. In the present work we describe a molecular model of cytotoxin- 1 in complex with chymotrypsin, prepared by the online server ClusPro. Analysis of the molecular model shows that Cytotoxin-1 (P01467) binds to chymotrypsin through its loop I located near the N-terminus. The concave side of loop I of the toxin fits well in the substrate binding pocket of the protease. We propose Phe10 as the dedicated P1 site of the ligand. Being a potent inhibitor of the 20S proteasome, cytotoxin-1 (P01467) can serve as a potential antitumor agent. Already snake venom cytotoxins have been investigated for their ability as an anticancer agent. The molecular model of cytotoxin-1 in complex with chymotrypsin provides important information towards understanding the complex formation.

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  • IPEN-DOC 27112

    HERNANDES, CAMILA; SILVA, BRUNA da; KLINGBEIL, MARIA de F.G. ; MATHOR, MONICA B. ; PEREIRA, ANA M.S.; SEVERINO, PATRICIA. Avoiding chemotherapy resistance in squamous cell carcinomas: anticancer activities of terpenoids and their impact on the regulation of microRNAs. Cancer Research, v. 77, 13 Supplement, 2017. DOI: 10.1158/1538-7445.AM2017-5456

    Abstract: MicroRNAs are small noncoding RNAs that play important roles in cellular biology. They have been implicated in pharmacogenomics by down-regulating genes that are essential for drug function. In this work we verified the potential anticancer activity of the quinone methide triterpenes maytenin and 22-β-hydroxymaytenin, as well as of a quinone methide triterpene-rich extract obtained from cultivated Maytenus ilicifolia root cells, and evaluated the associated microRNA expression following half maximal inhibitory concentration (IC50) treatment. Standard selectivity index (SI) for the isolated compounds and the root cell extract was determined by the logarithmic shift in effective concentration (IC50) between cancer cell lines and oral keratinocytes. Both isolated molecules as well as the root cell extract presented pronounced antiproliferative and pro-apoptotic activities in four cell lines derived from head and neck squamous cell carcinomas, including a metastasis-derived cell line. A positive SI, with an average 2-fold increase in potency, was detected for single agents and for the extract. MicroRNA expression profiles were assessed at 24h, 48h and 72h following treatment and an average of 100 molecules presented consistent marked variation in expression levels. Considering associations of microRNAs, genes they regulate, and the drugs effects dependent on these genes, the down-regulation of miR-193a-3p and miR-21 in treated cells is of particular interest. Both microRNAs have been involved in 5-fluorouracil and cisplatin resistance, current agents of standard chemoradiotherapy for locally advanced head and neck cancer. Squamous cell carcinoma of the head and neck is one of the most common cancer types worldwide whereas treatment options based on conventional therapies or targeted therapies under development have limited efficacy. Plant-derived products are valuable sources for the development of new therapeutic options for cancer treatment or as synergistic agents in existing regular care.

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  • IPEN-DOC 27111

    REIS, S.L. ; MUCCILLO, E.N.S. . Ionic conductivity of doped lanthanum gallate and strontium gallate composites. ECS Transactions, v. 80, n. 9, p. 141-149, 2017. DOI: 10.1149/08009.0141ecst

    Abstract: Polycrystalline ceramic solid electrolytes based on strontium- and magnesium-doped lanthanum gallate exhibit high ionic conductivity and find potential application in solid oxide fuel cells operating at intermediate temperatures. Sintering of this solid electrolyte is usually carried out at high temperatures, being responsible for loss of Ga and consequent formation of impurity phases. In this work, composites consisting of La0.9Sr0.1Ga0.8Mg0.2O3-δ with additions of strontium gallate were prepared by solid state reaction, and the influence of the additiveon electrical conductivity and phase composition of the composite electrolyte was investigated. The sintered density of composites is higher than 95% of the theoretical value after sintering at 1350°C. The contents of impurity phases decreased with increasing additions of strontium gallate. The overall ionic conductivity of the composites is higher than that of LSGM. This effect is attributed to the decrease in the fraction of free MgO at grain boundaries in the composites.

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  • IPEN-DOC 27110

    MONTEIRO, WALDEMAR A. (Ed.) . Light Metal Alloys Applications. Rijeka, Croatia: Intech, 2014. 242 p. DOI: 10.5772/57069

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  • IPEN-DOC 27109

    MONTEIRO, WALDEMAR A. (Ed.) . New Features on Magnesium Alloys. Rijeka, Croatia: Intech, 2012. 174 p. DOI: 10.5772/2810

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  • IPEN-DOC 27108

    MONTEIRO, W.A. ; BUSO, S.J.; SILVA, L.V. da . Application of magnesium alloys in transport. In: MONTEIRO, WALDEMAR A. (Ed.). New Features on Magnesium Alloys. London, UK: IntechOpen, 2012. p. 1-14, cap. 7. DOI: 10.5772/48273

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  • IPEN-DOC 27107

    PEREIRA, VIVIAM S.M.; ANTUNES, RENATO A.; OLIVEIRA, MARA C.L. de; CORREA, OLANDIR V. . Efeito de tratamentos de envelhecimento sobre a resistência à corrosão da liga de magnésio AZ91D / Ageing heat treatments effect on the corrosion resistance of the AZ91D magnesium alloy. In: CONGRESSO INTERNACIONAL ANUAL DA ABM, 67th, July 31 - August 7, 2012, Rio de Janeiro, RJ. Proceedings... 2012. p. 192-202.

    Abstract: O efeito de tratamentos térmicos de envelhecimento (T6) sobre a resistência à corrosão da liga de magnésio AZ91D foi estudado. Amostras solubilizadas a 445°C por 24 h foram envelhecidas a 200 °C por tempos de 8 h, 16 h e 24 h. Todos os tratamentos foram realizados em forno mufla, sob atmosfera inerte (argônio), seguidos de resfriamento em água. Para observação das alterações microestruturais, utilizaram-se as técnicas de microscopia óptica e de MEV. O comportamento eletroquímico foi avaliado por ensaios de espectroscopia de impedância eletroquímica e de polarização potenciodinâmica, utilizando-se solução de Hanks, a 37 °C como eletrólito. O período de imersão foi de 7 dias. Com o tratamento de solubilização, ocorreu a dissolução do constituinte eutético, restando somente a matriz (fase α-Mg) saturada com alumínio, juntamente de resquícios de β- Mg17Al12. Com o tratamento de envelhecimento foram observados precipitados ricos em alumínio (β-Mg17Al12) sobre a matriz. A amostra envelhecida por 8 h foi a que mostrou menor valor de resistência à corrosão; as amostras tratadas por 16 h e 24 h apresentaram valores de impedância semelhantes, sendo que a amostra envelhecida por 16 h apresentou o melhor desempenho.

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  • IPEN-DOC 27106

    RODRIGUES, ANTONIO C.I. ; MADI FILHO, TUFIC ; SILVA, DAVILSON G. da . Analysis and construction of the high density storage racks for spent fuel of the research reactor IEA-R1. RAD Conference Proceedings, v. 3, p. 123-126, 2018. DOI: 10.21175/RadProc.2018.27

    Abstract: The IEA-R1 research reactor works 40h weekly, with 4.5 Mw power. The storage rack for spent fuel elements has less than half of its initial capacity. Under these conditions, the reactor operating for 32h/week will have 3 spent fuel by year, approximately 3 utilization rate Positions/year; thus, we will have only about six years of capacity for storage. Since the desired service life of the IEA-R1 is at least another 20 years, it will be necessary to increase the storage capacity of spent fuel by doubling the wet storage in the reactor’s pool. 3M’s neutron absorber BoralcanTM was chosen after reviewing the literature about available materials for the construction of a new storage rack. This work presents studies for the construction of new storage racks with double of capacity using the same place of the current ones. Criticality safety analysis was performed with MCNP-5 Monte Carlo code, using two Evaluated Nuclear Data Files (ENDF/B-VI and ENDF/B-VII) in calculations, and subsequently, the results were compared. The full charge of the storage rack with only new fuel elements (maximum reactivity) was considered to calculate the keff. The results obtained in the simulations show that it is possible doubling the storage capacity of the spent fuel elements. Additionally, it complies with safety limits established by International Atomic Energy Agency (IAEA) and Brazilian Commission of Nuclear Energy (CNEN) standards to the criticality criteria (keff <0.95). This is only possible with the use of neutron absorber material.

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  • IPEN-DOC 27105

    OTON, LAIS F.; OLIVEIRA, ALCINEIA C.; ARAUJO, JESUINA C.S. de; ARAUJO, RINALDO S.; SOUSA, FRANCISCO F. de; SARAIVA, GILBERTO D.; LANG, ROSSANO; OTUBO, LARISSA; DUARTE, GIAN C. da S.; CAMPOS, ADRIANA. Selective catalytic reduction of NOx by CO (CO-SCR) over metal-supported nanoparticles dispersed on porous alumina. Advanced Powder Technology, v. 31, n. 1, p. 464-476, 2020. DOI: 10.1016/j.apt.2019.11.003

    Abstract: The selective catalytic reduction of NOx by CO (CO-SCR) was investigated over metals supported on porous alumina. The Pt, Co, Fe and Ni nanoparticles were dispersed on the alumina and characterized by XRD, textural properties, FTIR spectroscopy, chemical analyses, Py adsorption followed by FTIR measurements, HRTEM and SEM-EDS. Among the solids studied, the Pt/Al2O3 and NiPt/Al2O3 catalysts exhibited improved performance due to the interaction and synergy between the Pt(Ni) nanoparticles and the support. In other words, the electron transfer facility between the PtOx(Ni) and chlorined Pt species on the support provided a more active solid in the CO-SCR reaction. The surface acidity of Lewis acid sites and the porous features of the Pt/Al2O3 and NiPt/Al2O3 catalysts also contributed significantly to the high performance of these materials in the NOx conversion. The Pt/Al2O3 and NiPt/Al2O3 catalysts were tolerant to the poisoning by SO2 and H2O and depicted a superior catalytic performance, compared to the other solids.

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  • IPEN-DOC 26678

    CABRAL, FERNANDA V. ; SABINO, CAETANO P.; DIMMER, JESICA A.; SAUTER, ISMAEL P. ; CORTEZ, MAURO J.; RIBEIRO, MARTHA S. . Preclinical investigation of methylene blue-mediated antimicrobial photodynamic therapy on Leishmania parasites using real-time bioluminescence. Photochemistry and Photobiology, v. 96, n. 3, p. 604-610, 2020. DOI: 10.1111/php.13188

    Abstract: Cutaneous leishmaniasis (CL) is a neglected disease that promotes destructive lesions. Difficulties in treatment are related to accessibility of drugs, resistance and toxicity. Antimicrobial photodynamic therapy (APDT) has been emerging as a promising treatment for CL. In this work, we evaluated methylene blue (MB)-mediated APDT (MB-APDT) on Leishmania amazonensis in vitro and in vivo by bioluminescence technique. In vitro, MB-APDT was performed using a red LED (k = 660 11 nm, 100 mW cm 2) and MB (100 μM) at different light doses. In vivo, mice were infected and 4 weeks later, randomly divided into three groups: control, APDT 1 (single session) and APDT 2 (two sessions of MB-APDT). MB was used at 100 μM and energy dose was established at 150 J cm 2. Parasite burden, lesion size and pain were evaluated weekly for 4 weeks. In vitro, lethal dose for 90% parasite inactivation was achieved at 48.8 J cm 2. In vivo, although APDT 1 and APDT 2 groups have showed similar parasite burden after 4 weeks, two sessions were clinically better, especially considering the inflammatory process associated to CL. Our findings reinforce MB-APDT as a costeffective treatment to combat CL.

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  • IPEN-DOC 26454

    LOBO, ALEXANDRE R.; GAIEVSKI, EDUARDO H.S.; MESQUITA, CARLOS H. de ; DE CARLI, EDUARDO; TEIXEIRA, PRYSCILA D.S.; PEREIRA, ROSA M.R.; BORELLI, PRIMAVERA; SÁ, LILIAN R.M. de; COLLI, CELIA. Increased adiposity by feeding growing rats a high-fat diet results in iron decompartmentalisation. British Journal of Nutrition, v. 123, n. 10, p. 1094-1108, 2020. DOI: 10.1017/S0007114519002320

    Abstract: The present study reports the effects of a high-fat (HF) diet of over 8 weeks on the Fe status of growing rats. Tissue Fe levels were analysed by atomic absorption spectrophotometry, and whole-body adiposity was measured by dual-energy X-ray absorptiometry. Histopathology and morphometry of adipose tissue were performed. Liver homogenates were used for measuring ferroportin-1 protein levels by immunoblotting, and transcript levels were used for Fe genes measured by real-time PCR. Tissue Fe pools were fit to a compartmental biokinetic model in which Fe was assessed using fourteen compartments and twenty-seven transfer constants (kj,i from tissue ‘i’ to tissue ‘j’) adapted from the International Commission on Radiological Protection (ICRP) 69. Ten kj,i were calculated from the experimental data using non-linear regression, and seventeen were estimated by allometry according to the formula ki;j ¼ a ×Mb. Validation of the model was carried out by comparing predicted and analysed Fe pool sizes in erythrocytes, the liver and the spleen. Body adiposity was negatively associated with serum Fe levels and positively associated with liver Fe stores. An inferred increase in Fe transfer from bone marrow to the liver paralleled higher hepatic Fe concentrations and ferritin heavy-chain mRNA levels in the HF diet-fed animals, suggesting that liver Fe accumulation occurred at least in part due to a favoured liver erythrocyte uptake. If this feeding condition was to be prolonged, impaired Fe decompartmentalisation may occur, ultimately resulting in dysmetabolic Fe overload.

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  • IPEN-DOC 25779

    AZEVEDO, JULIANA de S.; QUINTINO, MARILIA T.A.; ROGERO, SIZUE O. ; ZAMPIERI, MARIA C.T. ; ROGERO, JOSE R. . Histopathological changes in zebrafish exposed to sublethal concentrations of 89nm silver nanoparticles for application in environmental diagnostics. Human and Ecological Risk Assessment, v. 26, n. 5, p. 1207-1220, 2020. DOI: 10.1080/10807039.2018.1560219

    Abstract: The use of biomarkers as indicators of environmental contamination has been shown to be an excellent indicator of changes in biota. Histopathological lesions are commonly used in biomonitoring studies as they provide information regarding both acute and chronic exposure. The use of nanoparticle materials has been widespread in recent years. However, not much is known about their ecological effects on the natural environment. Thus, the aim of this study was to assess the sublethal effects of silver nanoparticles (AgNP) with mean diameters of 89nm in the zebrafish Danio rerio by the determination of the LC50; 48 h and histopathological assays in gills. The obtained LC50; 48 h was 8.18 mgL 1. The histopathological gill assessment showed primary responses indicative of acute damage as aneurysms (32.76%), hyperplasia (20.69%) and partial (30.17%) and total lamellar fusion (6.9%) of secondary lamellae. No deposition of AgNP was observed in any tested sample gills, suggesting other organs target to absorption and detoxification. In fact, the AgNP causes sublethal damage in the gills of zebrafish but is not able to accumulate in this tissue. Finally, the data shown in this study contribute to the construction of a database on the AgNP exposure in aquatic organisms.

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  • IPEN-DOC 25761

    BOIDI, G.; TERTULIANO, I.S.; PROFITO, F.J.; ROSSI, W. de ; MACHADO, I.F.. Effect of laser surface texturing on friction behaviour in elastohydrodynamically lubricated point contacts under different sliding-rolling conditions. Tribology International, v. 149, p. 1-9, 2020. DOI: 10.1016/j.triboint.2019.02.021

    Abstract: The Laser Surface Texturing (LST) technique has been largely investigated to improve the tribological performance of lubricated contacts. The present contribution is aimed at scrutinizing the influence of three texture configurations fabricated by LST on the tribological performance of elastohydrodynamic (EHD) point contacts under different slide-to-roll ratios (SRR), entrainment velocities and inlet temperatures. Friction experiments were conducted through a series of ball-on-disk tests in the MTM-2 (Mini-Traction Machine) tribometer. Main results showed that the texture configurations promoted significant effects under boundary and mixed lubrication conditions, and also affected the full-film EHD regime at higher temperatures. Furthermore, the tribological performance of textured samples was strongly related to the texture depth. Shallower texture designs (∼0.5 μm) reduced friction compared to untextured material, whereas deeper features (> 1 μm) generally led to detrimental results. In general, dimples configuration decreased the lift-off speed and promoted full-film EHD conditions for a larger range of speeds, whereas radial curved grooves yielded to friction reduction under mixed lubrication conditions, moving the transition from boundary to mixed regimes to lower speeds, especially for intermediate lubricant viscosity.

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  • IPEN-DOC 27104

    SANTOS, G.A. dos; FIGUEIREDO, W.; SCHMITT, Y.P.; NASCIMENTO, M.S.; MIRANDA, F.; BATALHA, G.F.; COUTO, A.A. . Study on closed-die forging in stainless steel as standard ASTM F138 in grain size function. In: ÖCHSNER, ANDREAS (Ed.); ALTENBACH, HOLM (Ed.). Engineering Design Applications II: Structures, Materials and Processes. Cham, Switzerland: Springer Nature Switzerland, 2020. p. 133-153, (Advanced Structured Materials, 113). DOI: 10.1007/978-3-030-20801-1_10

    Abstract: Forging is a bulk deformation process in metal working commonly employed in the manufacture of metallic materials prostheses. Depending on the compressive loads applied to the material, structures (grain sizes) are formed which increase its strength. By forging an ASTM F138 stainless steel, the heating of material in a suitable temperature is of fundamental importance to be formed without the presence of folds arising from the process and as a result we can obtain a proper microstructure. This work aims to define the accurate temperature in relation to the strain rate applied in the hot die forging process. Besides, it is used a closed-die forging in which cavity has different thickness that stimulates the profile of an orthopedic plate. Four ranges of temperature used in the process vary between 1000 and 1200 °C, with a strain rate ranging from 400 to 600 s−1.Results demonstrate that there is a transitional temperature close to 1050 °C, where temperatures of 1000–1040 °C provide satisfactory grain size and temperatures of 1100 and 1200 °C, showed limitations in grain size, greater than those recommended by ASTM F 621.

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  • IPEN-DOC 27103

    MACHADO, ALESSANDRA C.F.E. (Ed.); HONÓRIO, DANIEL H. (Ed.); PEREIRA, DÉBORA A. (Ed.); LIMA, ADRIANA T. de (Ed.); AQUINO, AFONSO R. de (Ed.); CORDOVIL, CLEBER de S. (Ed.); NICOLETTI, HENRIQUE P. (Ed.); SANTOS, JOSÉ R. (Ed.); SILVA, KARINA M. da (Ed.); MAIA, LUIZ C. (Ed.); POPST, LUIZ A.A. (Ed.); SANTOS, MARIA L.D.P. (Ed.); SANTOS, MARIANA (Ed.); WILLMERSDORF, OFÉLIA de F.G. (Ed.); DIAS, PAULO E.V. (Ed.); SARACURA, VALÉRIA F. (Ed.); COIMBRA, VINÍCIUS P. (Ed.) . I Workshop sobre Educação Ambiental: Resultados e Encaminhamentos. Brasília, DF; Araçoiaba da Serra, SP: ICMBio; FLONA de Ipanema, 2018. 112 p.

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  • IPEN-DOC 27102

    INSTITUTO DE PESQUISAS ENERGÉTICAS E NUCLEARES (Ed.); SAKATA, SOLANGE K. (Coord.); RODRIGUES, DEBORA F. (Coord.); OYANEDEL-CRAVER, VINKA (Coord.) . Conference Proceedings of 1st Pan American Congress of Nanotechnology: Fundamentals and Applications to Shape the Future - PanNano 2017. São Paulo, SP, 2018. 257 p.

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  • IPEN-DOC 27101

    MIZUTANI, GUSTAVO ; VEGA, OSCAR . Análise de agrotóxicos em alimentos vegetais com alto teor de proteínas via cromatografia acoplada a espectrometria de massas tandem. In: CONGRESSO ANALITICA, 6th.; CONGRESSO ANALITICA LATIN AMERICA, 15th.; NANO TRADE SHOW; CIRCUITO DO CONHECIMENTO E INOVAÇÃO, September 24-26, 2019, São Paulo, SP. Poster... 2019.

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ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.