INSTITUTO DE PESQUISAS ENERGÉTICAS E NUCLEARES
Repositório Digital da Produção Técnico Científica

Navegação IPEN por Agências de fomento "Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)"

Navegação IPEN por Agências de fomento "Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)"

Classificar por: Ordenar: Resultados:

  • IPEN-DOC 26133

    ABREU, RODRIGO T. ; ANGELOCCI, LUCAS V. ; NOGUEIRA, BEATRIZ R. ; SANTOS, HAMONA N. dos ; ZEITUNI, CARLOS A. ; ROSTELATO, MARIA E.C.M. . Anisotropy function of a new 192-Ir brachytherapy source. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 175-185.

    Abstract: Brachytherapy is a type of radiotherapy that uses radioactive sources (seeds, wires, among others) close to the tumor. Is important to provide a detailed description of seed dosimetry, so only the tumor will be irradiated avoiding unnecessary dose on adjacent organs and structures. To evaluate the dosimetric parameter of the anisotropy function for a new brachytherapy source, this work proposes the use of microcube TLD-100 dosimeters to find the dose rate using the AAPM Task Group 43 protocol (TG-43). The anisotropy function represents dose distribution around the source and has a major role for characterization of a new iridium source being implemented in Brazil. The value of D(r,θ) was measured using Solid Water phantoms, r value being the distance from the geometric center of the source to the position of the dosimeter on the phantom, and θ being the angle formed between the longitudinal axis of the source and the line connecting the geometric center to the TLD. Monte Carlo calculations were performed to evaluate the anisotropy function to validate the experimental measurements. For each distance value (r), an anisotropy function was plotted (1.0, 2.0, 3.0, 4.0, 5.0, and 10.0 cm). The results obtained with Monte Carlo calculations agreed ±2% with the experimental values for r greater than 3.0 cm, so these results show a good distribution of dose around the seed considering the high energy of 192-Ir (average of 380 KeV) and encapsulation thickness.

    Palavras-Chave: anisotropy; brachytherapy; dose rates; dosimetry; iridium 192; monte carlo method; phantoms; radiation dose distributions; radiation source implants; sealed sources; thermoluminescent dosemeters

    Como referenciar este item
    Icon

  • IPEN-DOC 27901

    ABREU, R.T. ; ANGELOCCI, L.V. ; NOGUEIRA, B.R. ; SANTOS, H.N. ; ZEITUNI, C.A. ; ROSTELATO, M.E.C.M. . Anisotropy function of a new 192-Ir brachytherapy source. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-15, 2021. DOI: 10.15392/bjrs.v9i1A.1506

    Abstract: Brachytherapy is a type of radiotherapy that uses radioactive sources (seeds, wires, among others) close to the tumor. Is important to provide a detailed description of seed dosimetry, so only the tumor will be irradiated avoiding unnecessary dose on adjacent organs and structures. To evaluate the dosimetric parameter of the anisotropy function for a new brachytherapy source, this work proposes the use of microcube TLD-100 dosimeters to find the dose rate using the AAPM Task Group 43 protocol (TG-43). The anisotropy function represents dose distribution around the source and has a major role for characterization of a new iridium source being implemented in Brazil. The value of D(r,θ) was measured using Solid Water phantoms, r value being the distance from the geometric center of the source to the position of the dosimeter on the phantom, and θ being the angle formed between the longitudinal axis of the source and the line connecting the geometric center to the TLD. Monte Carlo calculations were performed to evaluate the anisotropy function to validate the experimental measurements. For each distance value (r), an anisotropy function was plotted (1.0, 2.0, 3.0, 4.0, 5.0, and 10.0 cm). The results obtained with Monte Carlo calculations agreed ±2% with the experimental values for r greater than 3.0 cm, so these results show a good distribution of dose around the seed considering the high energy of 192-Ir (average of 380 KeV) and encapsulation thickness.

    Palavras-Chave: anisotropy; brachytherapy; dose rates; dosimetry; iridium 192; monte carlo method; phantoms; radiation dose distributions; radiation source implants; sealed sources; thermoluminescent dosemeters

    Como referenciar este item
    Icon

  • IPEN-DOC 24876

    OLIANI, WASHINGTON L. ; PARRA, DUCLERC F. ; KOMATSU, LUIZ G.H. ; LINCOPAN, NILTON; RANGARI, VIJAYA K.; LUGAO, ADEMAR B. . Antibacterial effect of silver incorporated polyethylene blown film for active packaging use. In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 2433-2437.

    Abstract: Food packaging is used to maintain the quality and safety of food products during storage and transportation, and to extend the shelf-life of food products. This is done by preventing unfavourable factors or conditions such as oxygen, light, moisture, spoilage microorganisms, chemical contaminants, mechanical resistance, etc. To be able to do so, packaging materials provide physical protection and also create the proper physicochemical conditions for each product necessary to obtain adequate shelf life and maintain food quality and safety. We report the preparation of polyethylene blown films containing silver nanoparticles by using the ultrasound technique. The silver nitrate was mixed with the surfactant oleic acid (AO) and sonicated for 30 minutes. This solution was mixed with polyethylene using a rotary mixer for 12 hours. Nanocomposites of low density polyethylene (LDPE) with linear low density polyethylene (LLDPE) blends and silver nanoparticles were prepared under melt in a twin screw extruder, using PE-g-MA as compatibilizer agent, ethylene graft maleic anhydride copolymer. The films were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), field emission scanning electron microscopy (FESEM), differential scanning calorimetry (DSC), percentage reduction of colony-forming units (CFU). The bacterial effect of Escherichia coli and Staphylococcus aureus were assessed in detail.

    Como referenciar este item
    Icon

  • IPEN-DOC 21675

    TERADA, MAYSA ; RAMASCO, BRUNO T.; SIMOES, ALDA M.P.; PADILHA, ANGELO F.; COSTA, ISOLDA . Aplicação da microscopia eletroquímica de varredura no estudo da corrosão do aço inoxidável DIN W. Nr. 1.4460 com alto teor de nitrogênio. In: CONGRESSO BRASILEIRO DE CORROSAO, 28.; INTERNATION CORROSION MEETING, 2nd, May 12-16, 2008, Recife, PE. Anais... 2008. p. 1-21.

    Abstract: Neste trabalho, a microscopia eletroquímica de varredura (SECM) foi usada para investigar a concentração de espécies químicas liberadas pela corrosão e avaliar a resistência à corrosão localizada do aço inoxidável austenítico DIN W. Nr. 1.4460 com alto N. Este material apresenta potencialidade para aplicação como biomaterial pela completa ausência de fases ferromagnéticas. O potencial do ultra microeletrodo detectou não somente íons Fe2+ nas áreas anódicas, mas também o empobrecimento em oxigênio nas regiões catódicas. O aço foi ensaiado nas condições como recebido e solubilizado. Os resultados indicaram que o material como recebido apresenta superfície mais ativa que a do solubilizado. Análise da superfície por “Field Emission Gun” (FEG-SEM) mostrou grande quantidade de Cr2N os quais atuaram como nucleadores de pites, e que a corrosão se inicia na interface precipitado de nitreto/matriz.

    Palavras-Chave: corrosion; stainless steels; austenitic steels; corrosion resistance; nitrogen; surgical materials

    Como referenciar este item
    Icon

  • IPEN-DOC 29514

    SILVA FILHO, JORGE C.; SILVA, SUELANNY C. da; VENANCIO, EVERALDO C.; TAKIISHI, HIDETOSHI ; ABE, IGOR Y.; SOARES, EDSON P. ; ANTUNES, RENATO A.; REY, JOSE F.Q.; MARTINEZ, LUIS G. ; ESCOTE, MARCIA T.. Aplicação de derivados de grafeno em baterias e ímãs permanentes / Application of graphene derivatives in batteries and permanent magnets. Revista da ABPN, v. 14, n. 41, p. 124-142, 2022. DOI: 10.31418/2177-2770.2022.v14.n41.p124-142

    Abstract: O presente trabalho aborda o estudo sobre a importância tecnológica dos compostos de grafeno, evidenciando a síntese, a caracterização do óxido de grafeno (GO) e óxido de grafeno reduzido (rGO) e suas aplicações em baterias e imãs permanentes de neodímio-ferro-boro. Os resultados de difração de raios-X mostraram a presença de apenas um pico em aproximadamente 2θ = 11°, o qual corresponde ao conjunto de planos de GO em (002). Os resultados das aplicações são: O eletrodo negativo da Bateria2 com 1% de adição de GO apresentou uma capacidade de descarga de 397,03 mAh/g e maior estabilidade cíclica durante os 30 ciclos. No caso dos imãs, o imã2, com 0,1% em massa de rGO mostrou os maiores valores de Br = 10,42 T, BHmax = 21,19 MGOe, ρ = 7135 kg m-3 e FQ = 0,63.

    Como referenciar este item
    Icon

  • IPEN-DOC 27944

    KOMATSU, LUIZ G.H. ; OLIANI, WASHINGTON L. ; LUGAO, ADEMAR B. ; PARRA, DUCLERC F. . Aplicação de ZnO como carregador de prata em uma blenda de HMSPP/SEBS visando ação biocida / Aplication of ZnO as carrier of silver in the blend of HMSPP/SEBS for biocide activity. In: CONGRESSO BRASILEIRO DE POLÍMEROS, 15., 27-31 de outubro, 2019, Bento Gonçalves-RS. Anais... São Carlos, SP: Associação Brasileira de Polímeros, 2019. p. 2356-2359.

    Abstract: Este estudo consiste em utilizar o óxido de zinco (ZnO) como carregador de nanoprata metálica (Ag°). Foi testado um método para síntese das partículas com a prata, o método de Turkevich. A confecção dos filmes poliméricos em matriz de HMSPP/SEBS foi realizada via processamento no estado fundido em extrusora. Os materiais obtidos foram caracterizados pelas técnicas de DLS, MEV e ensaios biocidas. As partículas apresentaram-se em tamanhos variando entre 100 à 200 nm, juntamente a isso, elas também apresentaram resultados de morte celular nos ensaios biocidas com as bactérias E.coli e S.aureus de acordo com a norma JIZ 2801.

    Palavras-Chave: films; polymers; zinc oxides; nanoparticles; silver; disinfectants; bacteria

    Como referenciar este item
    Icon

  • IPEN-DOC 28849

    GODOI, CAMILA M. ; SANTOS, MONIQUE C.L. ; NUNES, LIVIA C. ; SILVA, ARACELI J. ; RAMOS, ANDREZZA S. ; SOUZA, RODRIGO F.B. de ; NETO, ALMIR O. . Application of binary PdSb/C as an anode in a polymeric electrolyte reactor-fuel cell type for electrosynthesis of methanol from methane. Materials Research, v. 25, p. 1-8, 2022. DOI: 10.1590/1980-5373-MR-2021-0542

    Abstract: PdSb catalyst prepared in different compositions were applied as an anode in a polymeric electrolyte reactor - fuel cell type (PER-FC) to convert methane into oxygenated products and energy in mild conditions. The PER-FC polarization curves for Pd90Sb10/C presented maximum current density about 0.92 mW cm-2 about 15% higher than PdSb materials. However, the material Pd50Sb50/C showed higher reaction rate for methanol generation than the other materials occurring close to the OCV (r ~ 7 mol L-1 h-1). The qualitative analyses of PER-FC effluent by FT-IR identified products as methanol, carbonate and formate ions from the partial oxidation of methane for all materials.

    Palavras-Chave: antimony; catalysts; cogeneration; current density; electrolytic cells; fourier transformation; fuel cells; methane; methanol; oxidation; palladium

    Como referenciar este item
    Icon

  • IPEN-DOC 25738

    ROVANI, S. ; MEDEIROS, L.F.; LIMA, E.C.; FERNANDES, A.N.. Application of biochar from agro‑industrial waste in solid‑phase extraction for the determination of 17β‑estradiol from aqueous solution. International Journal of Environmental Science and Technology, v. 16, n. 12, p. 7623-7630, 2019. DOI: 10.1007/s13762-019-02295-6

    Observação: Correction anexado. International Journal of Environmental Science and Technology, v. 16, p. 7631, 2019. DOI: 10.1007/s13762-019-02433-0

    Abstract: In this study, the biochar produced from coffee wastes and eucalyptus sawdust was employed as an adsorbent in solid-phase extraction devices for the determination of 17β-estradiol from aqueous solution. Parameters such as adsorbent mass, solvent type, eluent volume, ionic strength, breakthrough volume, and the cartridge reuse were evaluated. The best experimental conditions for solid-phase extraction concerning adsorbent mass, elution solvent, eluent volume, ionic strength, breakthrough volume, and cartridge reuse were established. The most suitable conditions for 1.0-mL cartridge were: mass of 50 mg, elution solvent 5.0 mL of acetonitrile/water 90:10 (v:v), 0.003 mol L−1 NaCl concentration, and 17β-estradiol solution volume 50.0 mL. The solid-phase extraction results showed that, although 17β-estradiol recovery was about 60%, the removal efficiency was 100% and the cartridges of 200 and 500 mg can be reused eight and four times, respectively, without any decrease in adsorption capacity. The results demonstrate the potential use of biochar as new adsorbent in solid-phase extraction devices for the removal of estrogens in aqueous solution.

    Palavras-Chave: charcoal; wood fuels; solid wastes; adsorbents; hormones; estradiol; agriculture; agricultural wastes

    Como referenciar este item
    Icon

  • IPEN-DOC 26141

    COTIS, DÉBORA S.; MARQUES, LEILA S.; FIGUEIREDO, ANA M.G. ; CORVAL, ARTUR; VALENTE, SÉRGIO C.. Application of neutron activation analysis to the study of low-titanium tholeiitic dykes of the Serra do Mar Swarm (RJ). In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 330-343.

    Abstract: The tholeiitic dykes of the Serra do Mar Swarm (SMS) outcrop along the coast of the São Paulo and Rio de Janeiro states (Southeastern Brazil), spreading over the Rio Paraiba Valley. Previous studies carried out in such dykes showed that they are related to the tectonic and magmatic processes that took place during the South Atlantic Ocean opening and gave rise to the Paraná Magmatic Province (PMP). The dykes are vertical to subvertical and preferentially NE-SW trending, with thicknesses ranging from centimeters to tens of meters. Most of the SMS intrusive rocks have relatively high concentrations of TiO2 (>3wt%), except for occurrences in the Região dos Lagos (Costa Azul Suite), as well as around Nova Friburgo Town (Serrana Suite), where they are characterized by basic rocks with low TiO2 (<2wt%) contents, whose genesis are still not completely understood. Therefore, a detailed study is being carried out in rocks of the Suite Serrana, with the determination of the concentrations of the rare earth (REE: La, Ce, Nd, Sm, Eu, Tb, Yb, and Lu) and other trace (Ta, Th, U, Hf, Cs, Sc, and Co) elements by instrumental neutron (thermal and epithermal) activation analysis, which has accuracy and precision required for petrogenetic studies. The data obtained so far show a substantial enrichment of highly incompatible trace elements (light REE, Th and U) and a remarkable geochemical similarity with the low-TiO2 basaltic flows of Gramado type found in southern PMP, suggesting important processes of crustal contamination during the genesis of the investigated dykes.

    Palavras-Chave: elements; geology; igneous rocks; neutron activation analysis; radioisotopes; titanium; trace amounts; brazil

    Como referenciar este item
    Icon

  • IPEN-DOC 23215

    VILLANI, DANIEL; MANCINI, ANSELMO; HADDAD, CECILIA M.K.; CAMPOS, LETICIA L. . Application of optically stimulated luminescence ‘nanoDot’ dosimeters for dose verification of VMAT treatment planning using an anthropomorphic stereotactic end-to-end verification phantom. Radiation Measurements, p. 1-5, 2017. DOI: 10.1016/j.radmeas.2017.03.027

    Abstract: This paper aims to evaluate the performance of the commercial OSL Landauer InLight System to be applied in dosimetric measurements in a Volumetric Modulated Arc (VMAT) brain tumor planning treatment using a Stereotactic End-To-End Verification Phantom Patient (STEEV™ – CIRS), comparing its results with CaSO4:Dy TLD pellets manufactured and marketed by the Laboratory of Dosimetric Materials/IPEN, PTW PinPoint™ ion chamber and Eclipse 10.0 planning system. The results of commercial InLight™ System using the nanoDot dosimeters showed good reproducibility and stability in both laboratory and clinical measurements. The experimental dose values obtained by all dosimetric techniques varied less than ±1.0% from prescribed by Eclipse 10.0. The intrinsic precision and uncertainty of the OSL reading device were found fair enough, providing good experimental results for VMAT dosimetry.

    Palavras-Chave: thermoluminescent dosemeters; photoluminescence; volumetric analysis; radiotherapy; dosimetry

    Como referenciar este item
    Icon

  • IPEN-DOC 28318

    SILVA, DANIEL J. da; PARRA, DUCLERC F. ; WIEBECK, HELIO. Applying confocal Raman spectroscopy and different linear multivariate analyses to sort polyethylene residues. Chemical Engineering Journal, v. 426, p. 1-13, 2021. DOI: 10.1016/j.cej.2021.131344

    Abstract: High-Density Polyethylene (HDPE), Low-Density Polyethylene (LDPE), Polypropylene (PP), and recycled Poly(Ethylene Terephthalate) (PET) are widely applied as packaging materials worldwide, and they correspond to more than 50 % of the plastic residues present in municipal solid waste. Currently, it is needed to develop effective methods to ensure the identification and sorting of plastic waste to guarantee necessary purity to obtain quality and economically viable recycled goods from post-consumer plastic. As an attempt to that, we investigated the applicability of Confocal Raman Scattering Spectroscopy (Confocal Raman) combined with Principal Component Analysis (PCA), Linear Partial Least Squares Regression by Intervals (iPLS-R) and Competitive Adaptive Weighted Sampling (CARS/PLS-R) as fast chemometric tools to identify and classify pristine and recycled mixtures of HDPE and LDPE from municipal solid waste in São Paulo, Brazil. We found several limitations in applying this procedure to classify the different polyethylenes and their polymer blends using the Principal Components (PC) from PCA analysis. iPLS-R regression model presents more effectiveness than the CARS/PLS-R model to detect the LDPE content in recycled HDPE/LDPE blends, both being influenced by different contaminants (PP, PET, SiO2, and CaCO3) added in these recycled plastics.

    Palavras-Chave: raman spectroscopy; polyethylenes; wastes; plastics; thermal gravimetric analysis

    Como referenciar este item
    Icon

  • IPEN-DOC 24306

    ANTONIO, PATRICIA L. ; CALDAS, LINDA V.E. . Applying the TSEE technique to Spectrolite and Opal pellets irradiated with high doses of gamma radiation. Radiation Measurements, v. 106, n. SI, p. 538-542, 2017. DOI: 10.1016/j.radmeas.2017.04.014

    Abstract: Spectrolite + Teflon and Opal + Teflon pellets were studied in this work in relation to their dosimetric properties, using the thermally stimulated exoelectron emission (TSEE) phenomenon. The purpose of this work was to study these materials to be used in high-dose dosimetry of Co-60 irradiators, which are employed for several industrial applications. The basic physical principle of this technique is the emission of low energy electrons from the surface of different crystalS. For this reason, it is very employed in work with specially radiation sources of low penetrating power, as alpha and beta radiation, but also with gamma sources. Both materials had already their dosimettic chatacteristics verified in previous works after exposure to high doses of a Co-60 source and measurements by means of thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques. The TSEE response was investigated in terms of the following tests: TSEE emission curves, reproducibility, minimum detectable doses and dose-response curves.

    Palavras-Chave: cobalt 60; crystals; dosimetry; exoelectrons; gamma radiation; gamma sources; irradiation; opals; pellets; radiation doses; silicates; teflon; thermoluminescence

    Como referenciar este item
    Icon

  • IPEN-DOC 29946

    NEGAHDARY, MASOUD; VELOSO, WILLIAM B.; BACIL, RAPHAEL P.; BUORO, RAFAEL M.; GUTZ, IVANO G.R.; PAIXAO, THIAGO R.L.C.; LAGO, CLAUDIMIR L. do; SAKATA, SOLANGE K. ; MELONI, GABRIEL N.; FRANCA, MESAQUE C.; OLIVEIRA, THAWAN G. de; AMEKU, WILSON A.; DURAZZO, MICHELANGELO ; ANGNES, LUCIO. Aptasensing of beta-amyloid (Aβ(1− 42)) by a 3D-printed platform integrated with leaf-shaped gold nanodendrites. Sensors and Actuators B: Chemical, v. 393, p. 1-11, 2023. DOI: 10.1016/j.snb.2023.134130

    Abstract: In this study, beta-amyloid (Aβ(1− 42)), an essential biomarker for diagnosing Alzheimer’s disease (AD), was detected via an electrochemical aptasensing platform. Here, an innovative signal transducer was developed using a CO2 laser-ablated 3D-printed electrode modified with leaf-shaped gold nanodendrites (LSG NDs, mean diameter: ~ 92 nm), which could provide an efficient interface for immobilizing aptamer strands. The modified electrode with LSG NDs exhibited an enhancement in its electrochemically active surface area about 7 times, compared with the bare electrode. This modification showed that the size, morphology, and distributions of LSG NDs in amplifying electrochemical signals might effectively provide a highly sensitive infrastructure for analyte detection. The strands of a thiol-functionalized aptamer sequence interacted with the gold surface, which created an optimized biointerface to detect Aβ(1− 42) in a linear range from 0.1 pg mL− 1 to 10 ng mL− 1 (limit of detection (LOD): 84 fg mL− 1 , (S/N = 3)). The developed aptasensor confirmed satisfactory stability, desired reproducibility and regeneration, and minimal impact of interfering agents. In addition, the application of this aptasensor was monitored via an assay of spiked analyte concentrations in 20 samples, including cerebrospinal fluid (CSF) and human serum.

    Como referenciar este item
    Icon

  • IPEN-DOC 28812

    MOREIRA, GREGORI de A. ; OLIVEIRA, AMAURI P. de; CODATO, GEORGIA; SANCHEZ, MACIEL P.; TITO, JANET V.; SILVA, LEONARDO A.H. e; SILVEIRA, LUCAS C. da; SILVA, JONATAN J. da ; LOPES, FABIO J. da S. ; LANDULFO, EDUARDO . Assessing spatial variation of PBL height and aerosol layer aloft in São Paulo Megacity using simultaneously two lidar during winter 2019. Atmosphere, v. 13, n. 4, p. 1-16, 2022. DOI: 10.3390/atmos13040611

    Abstract: This work presents the use of two elastic lidar systems to assess the horizontal variation of the PBL height (PBLH) and aerosol layer aloft in the São Paulo Megacity. These two lidars performed simultaneous measurements 10.7 km apart in a highly urbanized and relatively flat area of São Paulo for two winter months of 2019. The results showed that the PBLH differences display diurnal variation that depends on the PBL during daytime growth phases. Cloud and sea breeze effects control most of PBLH variation. In the absence of cloud and sea breeze, the maximum difference (~300 m) occurs in the rapid development stage and is due to topographic effects. When the PBL approaches its maximum daily value, it tends to level off with respect to the topography. In addition, it was presented a method that combines elastic lidar (to detect an aerosol layer) and satellite data (to classify such a layer from Aerosol Optical Depth (AOD) and Aerosol Index (AI) information) for the detection of biomass burning events. This methodology demonstrated that the variations caused by Biomass Burning in AOD and AI enable both the detection of aerosol plumes originating from biomass burning and the identification of their origin.

    Palavras-Chave: boundary layers; earth atmosphere; biomass; burns; urban areas; optical radar

    Como referenciar este item
    Icon

  • IPEN-DOC 26766

    LIMA, CASSIO A. ; CORREA, LUCIANA; BYRNE, HUGH J.; ZEZELL, DENISE M. . Assessing the spectrochemical signatures of skin components using FTIR microspectroscopy. In: QUINCY BROWN, J. (Ed.); VAN LEEUWEN, TON G. (Ed.) EUROPEAN CONFERENCES ON BIOMEDICAL OPTICS, June 23-27, 2019, Munich, Germany. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 110730S-1 - 110730S-3. (Proceedings of SPIE-OSA Vol. 11073, Clinical and Preclinical Optical Diagnostics II). DOI: 10.1117/12.2527137

    Abstract: Fourier Transform Infrared (FTIR) spectroscopy is a label-free analytical technique used to evaluate the chemical profile of a sample based on its molecular vibrations. The potential dermatological applications of FTIR spectroscopy has been well demonstrated over the past decades through many proof-of-concept studies evaluating cancerous and non-cancerous cutaneous diseases. Considering that the correctly identification of skin components plays an important role in the study of cutaneous diseases, the present study aims to evaluate the spectrochemical signatures of dermis and epidermis based on the pixels of a FTIR hyperspectral image collected from healthy skin.

    Palavras-Chave: infrared spectrometers; skin; epithelium; cluster analysis

    Como referenciar este item
    Icon

  • IPEN-DOC 28871

    CASTRO, PEDRO A.A. de ; DIAS, DERLY A. ; DEL-VALLE, MATHEUS ; VELOSO, MARCELO N. ; SOMESSARI, ELIZABETH S.R. ; ZEZELL, DENISE M. . Assessment of bone dose response using ATR-FTIR spectroscopy: a potential method for biodosimetry. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, v. 273, p. 1-7, 2022. DOI: 10.1016/j.saa.2022.120900

    Abstract: The health care application of ionizing radiation has expanded worldwide during the last several decades. While the health impacts of ionizing radiation improved patient care, inaccurate handling of radiation technology is more prone to potential health risks. Therefore, the present study characterizes the bone dose response using bovine femurs from a slaughterhouse. The gamma irradiation was designed into low-doses (0.002, 0.004 and 0.007 kGy) and high-doses (1, 10, 15, 25, 35, 50 and 60 kGy), all samples received independent doses. The combination of FTIR spectroscopy and PLS-DA allows the detection of differences in the control group and the ionizing dose, as well as distinguishing between high and low radiation doses. In this way, our findings contribute to future studies of the dose response to track ionizing radiation effects on biological systems.

    Palavras-Chave: ionizing radiations; radiation doses; dosimetry; skeleton; biological dosemeters; fourier transformation; infrared radiation

    Como referenciar este item
    Icon

  • IPEN-DOC 27994

    CASTRO, PEDRO ; LIMA, CASSIO ; ZORN, TELMA; ZEZELL, DENISE M. . Assessment of burn wounds status using mid-infrared spectroscopy. In: SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, October 7-9, 2019, São Paulo, SP. Abstract... Piscataway, NJ, USA: IEEE, 2019. p. 20-21.

    Abstract: Burns are one of the major causes of morbidity and the most costly traumatic injuries worldwide. Better understanding of the molecular mechanisms associated with wound healing might provide improved clinical strategies to speed up the tissue repair process and reduce the global impact of burns on public health services. The traditional techniques used to assess the biochemical events related to wound repair are laborious, time-consuming and require multiple staining. Thus, the present study aims to evaluate the feasibility of Fourier transform infrared (FTIR) spectroscopy in order to monitor the progress and healing status of burn wounds. Third-degree burn injuries were induced on Wistar rats by water vapor exposure. Afterwards, biopsies specimen was extracted for further histopathological examination and spectroscopic evaluation at 4 time-points (3, 7, 14 and 21 days). Raw spectral data were offset-corrected and normalized by amide I band area. The second derivatives were compared by the Principal Component Analysis (PCA). On days 3 and 7, when compared to healthy group, biomolecules bands were most prominent. However, on days 14 and 21, these molecular bands decreased. Therefore, our pairwise comparison revealed that metabolic activity induced by thermal injury decreases as the healing process progresses. Our findings show that FTIR spectroscopy can monitor the biochemical development induced by burn injury and detect the status of wound repair.

    Como referenciar este item
    Icon

  • IPEN-DOC 27450

    AMARAL, M.M.; DEL-VALLE, M. ; RAELE, M.P. ; PRETTO, L.R. de ; ANA, P.A.. Assessment of osteoporosis through laser speckle imaging: an in vitro model. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Abstract... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 66-67.

    Como referenciar este item
    Icon

  • IPEN-DOC 29087

    GRANDIZOLI, D.R.P.; RENZO, A.L.M.; SAKAE, L.O.; LOPES, R.M.; ZEZELL, D.M. ; ARANHA, A.C.C.; SCARAMUCCI, T.. Assessment of the ability of desensitizing and conventional mouth rinses to promote dentin tubule occlusion. Operative Dentistry, v. 47, n. 5, p. 549-561, 2022. DOI: 10.2341/21-043-L

    Abstract: This study aimed to evaluate the effect of desensitizing and conventional mouth rinses on dentin tubule occlusion. Dentin hypersensitivity was simulated by EDTA application for five minutes. The specimens were randomly allocated into the following groups: desensitizing mouth rinses (Colgate Sensitive, Elmex Sensitive Professional, Listerine Advanced Defense Sensitive, Sensodyne Cool Mint); conventional mouth rinses (Colgate Plax, Elmex Caries Protection, Listerine Anticaries, Sensodyne Pronamel); a negative control (C−: distilled water); and Clinpro XT Varnish was the positive control (C+). Subsequently, the specimens were submitted to an erosive or abrasive challenge (performed separately) and to an erosive/abrasive cycling for five days (n=10 for each challenge). After treatment, challenges, and cycling, the specimens were analyzed in an environmental scanning electron microscope to verify the number of open dentin tubules (ODTs), counted by using Image J software (National Institutes of Health, Bethesda, MD, USA). Data were analyzed by the Kruskal-Wallis, Friedman and Dunn tests, with Bonferroni correction (α=0.05). Groups did not differ at baseline (p>0.05). At the post-treatment, erosion and abrasion stages, C+ was the only group that showed a reduction in ODTs compared to C−(p<0.05). In the other groups, numbers did not differ significantly from C− (p>0.05). After cycling, none of the groups exhibited significant reduction in ODTs other than C− (p>0.05); however, C+, Listerine Anticaries, and Colgate Plax had a lower number of ODTs than Listerine Sensitive and Sensodyne Pronamel. No mouth rinse was able to promote significant occlusion of the dentin tubules after treatment and the challenges. C+ was the only product that effectively promoted tubular occlusion, but this effect did not withstand several erosive and abrasive challenges.

    Palavras-Chave: oral cavity; dentistry; dentin; tubules; sensitivity

    Como referenciar este item
    Icon

  • IPEN-DOC 28066

    DIAS-MORAES, MARCIA C. ; CASTRO, PEDRO A.A. ; PEREIRA, DAISA L. ; ANA, PATRICIA A.; FREITAS, ANDERSON Z. ; ZEZELL, DENISE M. . Assessment of the preventive effects of Nd:YAG laser associated with fluoride on enamel caries using optical coherence tomography and FTIR spectroscopy. PLoS One, v. 16, n. 7, p. 1-14, 2021. DOI: 10.1371/journal.pone.0254217

    Abstract: Objective This in vitro study characterized and monitored, by Optical Coherence Tomography (OCT) and Fourier Transformed Infrared Spectroscopy (FTIR), the effects of the association of acidulated phosphate fluoride gel (APF-gel) and Nd:YAG (neodymiun:yttrium-aluminum-garnet) laser, as sequencial treatments, in the prevention of incipient enamel caries lesions. Methods 120 human enamel samples were randomized into 3 groups (n = 40): APF-gel (1.23% F-, 4 min.); Laser+APF (Nd:YAG laser irradiation—0.6W, 84.9J/cm2, 10Hz, followed by APF-gel); and APF+Laser (APF-gel followed by laser irradiation). The samples were subjected to a 15-day pH-cycling, evaluated by OCT (quantification of optical attenuation coefficient–OAC) and FTIR (analysis of carbonate and phosphate content) before treatments, after treatments, and on the 5th, 10th and 15th days of pH-cycling. The statistical analysis was performed (α = 5%). Results The Optical Attenuation Coefficient (OAC) assessed by OCT increases with the progression of demineralization, and the Laser+APF presented the highest values of OAC in 10th and 15th days of pH-cycling. Nd:YAG decreased the carbonate content after treatment regardless of the application order of the APF-gel, while APF-gel did not interfere in the composition of enamel. The carbonate content was also changed in the first 5 days of the pH-cycling in all groups. Conclusion Nd:YAG laser irradiation before or after the application of APF-gel did not influence the appearance of incipient caries lesions, showing no synergistic effect. Regardless of the application order of the APF-gel, laser irradiation reduces the carbonate content of the enamel, which also changes during the demineralization process. However, irradiation before the application of APF-gel increased the speed of progression of the lesions, which positively impacts public health as it can prevent caries disease, even in high risk individuals. OCT and FTIR are suitable for assessing this effect.

    Palavras-Chave: neodymium lasers; dentistry; enamels; laser radiation; fluorides

    Como referenciar este item
    Icon

A pesquisa no RD utiliza os recursos de busca da maioria das bases de dados. No entanto algumas dicas podem auxiliar para obter um resultado mais pertinente.

✔ É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

✔ A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

✔ Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.

Exemplo:

Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

✔ Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

✔ 95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

✔ Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

✔ O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

✔ Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

✔ Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

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.

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.

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.

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.