Repositório Digital - IPEN/SP: Submissões recentes

  • IPEN-DOC 23151

    ANGELO, EDVALDO; BARBOZA, RODOLFO A.R.; ANDRADE, DELVONEI A. de ; ANGELO, GABRIEL. Estudo numérico da inclusão de geradores de turbulência em canal com transferência de calor. In: CONFERENCIA IBEROAMERICANA EN SISTEMAS, CIBERNETICA E INFORMATICA, 15., 05-08 de julio, 2016, Orlando, USA. Anales... 2016. p. 50-57.

    Abstract: O artigo apresenta simulação numérica computacional de um escoamento em um canal de seção transversal retangular havendo transferência de calor entre as paredes e o fluido. O canal representa parte de um trocador de calor de placas de pequeno porte para aplicação em dispositivos eletrônicos. Foram realizadas simulações em que a geometria do canal recebeu alterações como a adição de geradores de turbulência objetivando o aumento da taxa de transferência de calor. As alterações consistiram na inclusão de ranhuras na parede e também a adoção de vários elementos geradores de turbulência na entrada do canal, em um total de quatro tipos geométricos distintos. Em uma das geometrias do gerador de turbulência, dois parâmetros foram variados e os resultados das simulações comparadas. As simulações computacionais foram realizadas utilizando o software comercial ANSYS CFX®. Os resultados indicaram a intensificação da transferência de calor nas geometrias modificadas e também a elevação da perda de carga do escoamento. É indicada a geometria mais adequada entre as propostas apresentadas.

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  • IPEN-DOC 23233

    SILVA, TAMIRES; ALVARENGA, LETICIA; LEAL, CINTIA; MIRANDA, BIANCA G.; SUZUKI, LUIZ C.; KATO, ILKA ; RIBEIRO, MARTHA ; PAVANI, CHRISTIANE; PRATES, RENATO . Incorporation of the methylene blue photosensitizer in the presence of glucose in strains of candida albicans with multidrug efflux systems. Lasers in Surgery and Medicine, v. 49, n. 4, p. 438-438, 2017.

    Abstract: Background: Infectious diseases are responsible for 60% of deaths in developing countries.Candida albicans cause severe infection in immunocompromised patients and the commonly used treatments have not been effective against microbial resistance. Photodynamic therapy (PDT) is a new promising strategy to microbial inactivation based on the use of photosensitizer (PS) in the presence of oxygen and activation by light to form reactive oxygen species.C.albicanshas glucose sensors which could facilitate the entrance of the PS. The objective of this study was to evaluate the role of glucose in the photodynamic inactivation of C. albicans. Study: C. albicans ATCC 10231, YEM 12, YEM 13, YEM 14, and YEM15were aerobically grown on Sabouraud agar and incubated at 308C for 24 hours. Microbial inoculants were divided into 4 groups with and without glucose: Control; Only irradiation; PS toxicity and PDT groups with three irradiation times.After going throughthe treatments, the colony-forming units were counted and the data were subjected to statistical analysis (ANOVA) and Tukey test. To measure the concentration ofMB, fluorescence spectroscopy and flow cytometry were used. Results: We observed that yeast with overexpression of Major Facilitator Superfamily membrane pore tend to accumulate more MB in its cytoplasm, whereas strains that overexpress ABC pumps demonstrated the greater survival against the photodynamic challenge. Conclusion: PDT is an efficient strategy against C. albicans and the presence of glucose can intervene in the photodynamic effect. The presence of MB in the intracellular region of the yeast predisposes to greater photodynamic inactivation, however, its germicidal capacity is related to the type and characteristics of the microbial.

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  • IPEN-DOC 23234

    MAIHARA, VERA A. ; FAVARO, DEBORAH I.T. ; BARBOSA JUNIOR, FERNANDO. Elementos Tóxicos. In: COUTINHO, WALTER L. (Ed.); COZZOLINO, SILVIA M.F. (Org.). Biodisponibilidade de nutrientes. 5 ed. Barueri, SP: Manole, 2016. p. 921-956.

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  • IPEN-DOC 23232

    LEAL, LUIZ; SANTOS, ADIMIR dos ; IVANOV, EVGENY; IVANOVA, TATIANA. Impact of 235U resonance parameter evaluation in the reactivity prediction. Nuclear Science and Engineering, v. 187, n. 2, p. 127-141, 2017. DOI: 10.1080/00295639.2017.1301739

    Abstract: Resonance parameter evaluation of the U-235 cross sections using the Reich-Moore formalism was done with the computer code SAMMY from 0 to 2.25 keV to address issues with capture cross-section and standard fission cross-section values. The evaluation includes recent capture and fission cross-section measurements as well as high-resolution data used in previous U-235 evaluation. Moreover the new U-235 resonance parameter evaluation has been used in the calculation of a new benchmark experiment performed at the IPEN/MB-01 research reactor. The experiment, named the inversion point of the isothermal reactivity coefficient, is used to test temperature effects at low temperature. The results demonstrate that the new U-235 evaluation has greatly improved the prediction of reactivity temperature coefficient in contrast to previous evaluations. This paper is outlined in two parts, namely the first part deals with the description of the U-235 resonance analysis and evaluation up to 2.25 keV, and the second part presents the results of the isothermal reactivity coefficient calculations performed on the IPEN/MB-01 reactor.

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  • IPEN-DOC 23231

    LEAL NETO, RICARDO M. ; SILVA, RAFAEL de A.; FLORIANO, RICARDO; COUTINHO, GRAZIELE C.S. ; FALCAO, RAILSON B. ; LEIVA, DANIEL R.; BOTTA, WALTER J.. Synthesis by high-energy ball milling of MgH2-TiFe composites for hydrogen storage. Materials Science Forum, v. 899, p. 13-18, 2017. DOI: 10.4028/www.scientific.net/MSF.899.13

    Abstract: The aim of this work is to investigate the influence of some processes variables on the microstructure and hydrogen absorption kinetics of MgH2 - X wt.% TiFe composites. Samples were synthesized by high-energy ball milling in a planetary (X = 40, 50, 60) and shaker mill (X = 40) under high-purity argon atmosphere. Commercial MgH2 instead of Mg powder was used in order to reduce adherence on the vial and balls. TiFe powder was previously produced by ball milling a mixture of TiH2 and Fe powders followed by a reaction synthesis at 600ºC. Milled composites samples were characterized by XRD and SEM analysis. Milling time was preliminary investigated (X = 40) in the planetary ball mill (6 to 36h). TiFe particle size reduction was shown to be difficult since they are surrounded by MgH2 matrix. Strong particle reduction was obtained by using a shaker mill only for 2 hours and adding cyclohexane as process control agent. No reaction between MgH2 and TiFe compound was observed in any milled sample. Hydrogen absorption kinetics measurements of the as-milled samples were conducted on an Sieverts' type apparatus at room temperature after hydrogen desorption at 350ºC under vacuum. The best hydrogen kinetics (3 wt% at the first hour) was attained by the planetary milled sample (36 h). Higher hydrogen capacity was observed for the sample milled in the shaker mill (4.0 wt.%), but only after 13h.

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  • IPEN-DOC 23230

    SILVA, GUSTAVO S. de A. e; LEAL NETO, RICARDO M. ; HENRIQUES, VINICIUS A.R.; CAIRO, CARLOS A.A.; RAMOS, ALFEU S.. Structural evaluation of mechanically alloyed W-50at%C powders. Materials Science Forum, v. 899, p. 9-12, 2017. DOI: 10.4028/www.scientific.net/MSF.899.9

    Abstract: Tungsten carbide is potentially attractive for development of catalysts and widely used for fabrication of cutting tools due to its high hardness and wear resistance while the ball milling can improve the mechanical properties from the metastable structures and nanomaterials. The aim of this work was to evaluate the phase transformations during milling of the W-50at%C elemental powder mixture under argon atmosphere in a planetary P-5 ball mill using WC-Co balls (10 mm diameter) and vials (225 mL), 200 rpm, and a ball-to-powder weight ratio of 10:1. Samples were collected into the vial after different times: 20, 60, 300 and 600 min. The as-milled W-50at%C powders were characterized by X-ray diffraction (XRD). Only peaks of W were identified in W-50at%C powders milled up to 600 min, which were broadened and moved to the direction of smaller diffraction angle. In addition, the lattice parameter and cell volume of W were reduced during ball milling of W-50at%C powders, indicating that the C atoms dissolved into the W lattice in order to form metastable structures. Carbon atoms were interstitially dissolved into the W lattice during the initial milling times, and its preferential substitutional dissolution was identified for longer times due to the larger amounts of crystallographic defects during ball milling.

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  • IPEN-DOC 23229

    SOARES, E.P. ; ZARPELON, L.M.C. ; FARIA, R.N. . The influence of Pr and Mg content on the hydrogen decrepitation of LaNi-based battery alloys. Materials Science Forum, v. 899, p. 148-153, 2017. DOI: 10.4028/www.scientific.net/MSF.899.148

    Abstract: This paper reports the results of investigations of the hydrogenation and decrepitation of some LaNi-based hydrogen storage cast ingot alloys. A decrepitation procedure for battery negative electrode alloys has been applied using a combination of hydrogen pressure and heating from room temperature to 773K. It has been shown that the Pr and Mg content have a significant influence on the microstructures of the hydrogenated alloys and decrepitation efficiency. Alloys with high concentration of Pr and Mg required an activation quenching treatment for starting the absorption of hydrogen. The decrepitated materials were characterized by scanning electron microscopy (SEM). Electrodes for alloy discharge capacity studies were produced using a nickel screen and electrochemical measurement were carried out in a standard three-electrode cell. The H content of the negative electrode, expressed as the number o H atoms (n) per formula unit, was determined using the measured storage capacity.

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  • IPEN-DOC 23228

    FERNANDEZ, ANTONIO P.R. ; GALEGO, EGUIBERTO ; FARIA, RUBENS N. . Thermal Influence on the electric parameters and microstructures of activated powder double layer supercapacitors. Materials Science Forum, v. 899, p. 260-265, 2017. DOI: 10.4028/www.scientific.net/MSF.899.260

    Abstract: The effect of the working temperature on the capacity, internal equivalent serial resistance (ESR), equivalent parallel resistances (EPR) of some retail available electric double layer capacitors (EDLC) have been investigated. Standard capacities of 1.0 F at a maximum potential of 5.5 V were employed in this study. EPR values have been calculated using the self-discharge curves at temperatures above to the nominal maximum working temperature of the supercapacitors (~70oC). The ESR values were measured during charge using the constant current (1 mAF-1) interrupt method with oscilloscope. Microstructural characterization of the electrode material have been carried out using scanning electron microscopy (SEM) and chemical microanalyses employing energy dispersive X-ray analysis (EDX).

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  • IPEN-DOC 23227

    CUNHA, SANDRA R.; GAROFALO, STEPHANIE A.; SCARAMUCCI, TAIS; ZEZELL, DENISE M. ; ARANHA, ANA C.C.. The association between Nd:YAG laser and desensitizing dentifrices for the treatment of dentin hypersensitivity. Lasers in Medical Science, v. 32, n. 4, p. 873-880, 2017. DOI: 10.1007/s10103-017-2187-9

    Abstract: This study aims to evaluate the association between Nd: YAG laser (with and without a photoabsorber) and two desensitizing dentifrices containing 15% NovaMin or 8% arginine, as potential treatments for dentin hypersensitivity (DH). DH was simulated by EDTA application for 2 min. Specimens were then analyzed with an environmental scanning electron microscope (ESEM) to ensure open dentin tubules (ODT), counted by using ImageJ software. Specimens were randomized into eight groups (n = 10): Laser (L), Laser+ Photoabsorber (LP), Arginine (A), Arginine+Laser (AL), Arginine+Laser+Photoabsorber (ALP), NovaMin (N), NovaMin+Laser (NL), and NovaMin+ Laser+ Photoabsorber (NLP). Laser irradiation was performed with 1 W, 100 mJ, 10 Hz, congruent to 85 J/cm(2); 4 irradiations of 10 s each, with 10 s intervals between them. After treatment, specimens were again analyzed by ESEM and submitted to erosive/abrasive cycling for 5 days. A final ESEM analysis was performed. Data were analyzed with two-way repeated measure ANOVA and Tukey tests (alpha = 0.05). After treatment, groups N, NL, and NLP presented the lower number of ODT, but they did not different from LP, ALP, and AL. Group A presented the highest number of ODT and it did not differ from group L. Groups L, AL, ALP, and LP presented intermediate results, without differing from each other. After cycling, group A presented the highest number of ODT and did not differ significantly from the other groups, except NLP. None of the associations tested presented better tubule occlusion than NovaMin by itself. Arginine was the only treatment that presented improved tubule occlusion when associated with Nd: YAG laser.

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  • IPEN-DOC 23226

    ZEISLER, ROLF; CHO, HANA; RIBEIRO JUNIOR, IBERE S. ; SHETTY, MARTIN G.; TURKOGLU, DANYAL. On neutron activation analysis with gamma gamma coincidence spectrometry. Journal of Radioanalytical and Nuclear Chemistry, v. 314, n. 1, p. 513-519, 2017. DOI: 10.1007/s10967-017-5342-7

    Abstract: A new gamma gamma coincidence system has been set up at NIST. It is operated with a digital data finder supported by new software developed at NIST. The system is used to explore possible enhancements in instrumental neutron activation analysis (INAA) and study applicability to neutron capture prompt gamma activation analysis (PGAA). The performance of the system is tested with certified reference materials for efficiency calibration and quantitative performance. Comparisons of INAA results based on conventional gamma-ray spectrometry data with INAA results based on coincidence data obtained from the same samples show improvements in the counting uncertainties and demonstrates the quantitative accuracy of the new system.

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  • IPEN-DOC 23225

    CAMPOS, LUIZA M.P. ; BOARO, LETICIA C.; SANTOS, TAMIRIS M.R. ; SANTOS, VINICIUS J. ; GRECCO-ROMANO, REBECA; SANTOS, MARIANA J.; PARRA, DUCLERC F. . Polymerization shrinkage evaluation in experimental dental composite filled with montmorillonite nanoparticles. Journal of Thermal Analysis and Calorimetry, 2017. DOI: 10.1007/s10973-017-6419-9

    Abstract: This study aimed to develop experimental dental restorative composites by the addition of montmorillonite (MMT) nanoparticles in a polymeric matrix-based BisGMA/TEGDMA, to assess the possibility of a different dimensional behavior during the photo-polymerization. The characterization of experimental composites was established with the following analyses: thermal–mechanical analysis (TMA), X-ray diffraction (XRD) and transmission electron microscopy. Data for TMA were analyzed using one-way ANOVA and Tukey test (p\0.05). It was observed that the experimental composites filled with MMT nanoparticle showed statistically similar polymerization shrinkage values (by TMA analysis) in the concentration of 30% and statistically lower polymerization shrinkage values in the concentration of 50%, compared to composites filled with barium glass (BG—control groups). These results may be related to the interaction polymeric matrix/MMT nanoparticles and the formation of nanocomposites, observed by XRD and TEM analyses.

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  • IPEN-DOC 23224

    RESTIVO, THOMAZ A.G. ; DURAZZO, MICHELANGELO ; MELLO-CASTANHO, SONIA R.H. de ; MOREIRA, ANA C.; GRACIANO, SERGIO; TELLES, VICTOR B.; TENORIO, JORGE A.S.. Low-temperature densification of ceramics and cermets by the intermediary stage activated sintering method. Journal of Thermal Analysis and Calorimetry, 2017. DOI: 10.1007/s10973-017-6560-5

    Abstract: The article explores new concepts in order to promote ceramic and cermet materials sintering at lower temperatures between 1200 and 1300 C. The principle of the new process method called intermediary stage activated sintering (ISAS) involves the preparation of the ceramic powder with dispersed doping agents, such as nanotubes and fibers, which shape the pore structure at pressed pellets with stable interconnected thin cylinders between the grains. This feature resembles and extends the condition found during the intermediary stage sintering, which enhances the ions diffusion rate along tubular pores to increase shrinkage. Carbon nanotubes (CNT) and nanofibers are homogenized into cubic zirconia and alumina in amounts ranging from 1 to 10 vol% at high-energy milling devices and ultrasound disruptor under ethanol media. Ni, Cu and Mo/MoO3 can be also added to provide tubular channel filling. Sintering of uniaxially pressed pellets is carried out in a dilatometer and tubular furnaces at 1200/1300 C under air, argon and controlled oxygen partial pressure atmospheres. TG/DTA/MS analyses of sample pellets reveal the oxidation and gas release temperature and duration. The results demonstrate the ISAS process concept is valid since it further increases the ceramic final density by 8% of the theoretical density at 1200 C, leading to close the porosity at 1300 C, compared to 1500–1600 C temperatures at conventional process. Short CNT and cellulose nanofiber were found to be the best additives in this sense.

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  • IPEN-DOC 23223

    BALDAN, RENATO; SILVA, ANTONIO A.A.P.; NUNES, CARLOS A.; COUTO, ANTONIO A. ; GABRIEL, SINARA B.; ALKMIN, LUCIANO B.. Solution and aging of MAR-M246 nickel-based superalloy. Journal of Materials Engineering and Performance, v. 26, n. 2, p. 465-471, 2017. DOI: 10.1007/s11665-016-2462-0

    Abstract: Solution and aging heat-treatments play a key role for the application of the superalloys. The aim of this work is to evaluate the microstructure of the MAR-M246 nickel-based superalloy solutioned at 1200 and 1250 C for 330 min and aged at 780, 880 and 980 C for 5, 20 and 80 h. The c¢ solvus, solidus and liquidus temperatures were calculated with the aid of the JMatPro software (Ni database). The as-cast and heattreated samples were characterized by SEM/EDS and SEM-FEG. The c¢ size precipitated in the aged samples was measured and compared with JMatPro simulations. The results have shown that the sample solutioned at 1250 C for 330 min showed a very homogeneous c matrix with carbides and cubic c¢ precipitates uniformly distributed. The mean c¢ size of aged samples at 780 and 880 C for 5, 20 and 80 h did not present significant differences when compared to the solutioned sample. However, a significant increasing in the c¢ particles was observed at 980 C, evidenced by the large mean size of these particles after 80 h of aging heat-treatment.

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  • IPEN-DOC 23222

    RESENDE FILHO, JOAO B.M.; SANTOS, PAULO R.; VALE, JULIANA A.; FAUSTINO, WAGNER M.; FARIAS, DANYELLE S.; BRITO, HERMI F.; FELINTO, MARIA C.F.C. ; TEOTONIO, ERCULES E.S.. Rare earth-indomethacinate complexes with heterocyclic ligands: synthesis and photoluminescence properties. Journal of the Brazilian Chemical Society, v. 28, n. 12, p. 2281-2290, 2017. DOI: 10.21577/0103-5053.20170079

    Abstract: In this work, synthesis, characterization and photophysical properties of trivalent rare earth complexes with a nonsteroidal anti-inflammatory drug [the indomethacinate (indo), presenting formulas RE(indo)(3)(H2O)(x) (x = 3, for Eu3+ and Gd3+, and x = 4 for Tb3+), RE(indo)(3)(bipy) and RE(indo)(3)(phen) (bipy: 2,2'-bipyridine, and phen: 1,10-phenanthroline)] were investigated. Based on photoluminescent results, the intramolecular energy transfer process from T-1 triplet states of indo, phen and bipy ligands to the D-5(0) emitting level of the Eu3+ ion in the coordination compounds is discussed. Accordingly, it is proposed two possible intramolecular energy transfer mechanisms between indomethacinate ligand and rare earth ions, which involve the participation of excited electronic states of the heterocyclic ligands as intermediate ones.

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  • IPEN-DOC 23221

    PIERETTI, EURICO F. ; NEVES, MAURICIO D.M. das . Laser marked and textured biomaterial evaluated by mott-schottky technique. International Journal of Electrochemical Science, v. 12, p. 9204-9211, 2017. DOI: 10.20964/2017.10.39

    Abstract: The effect of an optical fiber laser marking and texturing techniques on the surface of the ISO 5832-1 stainless steel via the Mott-Schottky approach was evaluated in this work. This is one of the most commonly used biomaterial for permanent implants manufacture. It was found that the pulsed laser treatment increases the susceptibility to corrosion by changes on the roughness, microstructure and surface chemical composition; which affect the surface passivity, comparatively to the non treated biomaterial. In this study, the Mott-Schottky technique was very sensitive to identify the effect of the type of surface treatment, marking and texturing, according to the laser pulse frequency modification on the electronic properties of the oxide layer. The change in the semiconductors behavior was the main procedure proposed to explain the increased susceptibility to localized corrosion associated to the areas affected by the Yb optical fiber laser engraving and texturing process.

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  • IPEN-DOC 23220

    MADUREIRA, JOANA; MELO, RITA; PIMENTA, ANDREIA I.; VERDE, SANDRA C.; BORRELY, SUELI I. . Evaluation of e-beam irradiation effects on the toxicity of slaughterhouse wastewaters. Environmental Technology, p. 1-5, 2017. DOI: 10.1080/09593330.2017.1313887

    Abstract: Slaughterhouse industry produces large volumes of polluted wastewater, which cause negative impacts on the environment. The objective of this study was to assess the effect of electronbeam irradiation on the ecotoxicity of slaughterhouse effluents with absorbed doses up to 35 kGy. Two acute toxicity assays were applied to evaluate the efficiency of irradiation onto toxicity of wastewater. The exposed living-organisms were a luminescent bacteria Vibrio fischeri, and a freshwater microcrustacean Daphnia similis. Also, the total organic carbon was analysed in order to determine any possible organic carbon removal after irradiation. The ecotoxicological results evidenced that both living-organisms were suitable for the measurements. Therefore, the results demonstrated the toxicity of the effluent and its similarity for both organisms as well as the potential of radiation to reduce these effects. The 35 kGy dose was very effective for reducing toxic effects of slaughterhouse wastewater for daphnids suggesting that ionizing radiation could be used as a tool for removing toxic charge of such effluents. The type of contamination presented by the effluent justify the needs for alternatives of treatment.

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  • IPEN-DOC 23219

    AL-YASIRI, A.Y.; KHOOBCHANDANI, M.; CUTLER, C.S.; WATKINSON, L.; CARMACK, T.; SMITH, C.J.; KUCHUK, M.; LOYALKA, S.K.; LUGAO, A.B. ; KATTI, K.V.. Mangiferin functionalized radioactive gold nanoparticles (MGF-198AuNPs) in prostate tumor therapy: green nanotechnology for production, in vivo tumor retention and evaluation of therapeutic efficacy. Dalton Transactions, 2017. DOI: 10.1039/c7dt00383h

    Abstract: We report here an innovative feature of green nanotechnology-focused work showing that mangiferin—a glucose functionalized xanthonoid, found in abundance in mango peels—serves dual roles of chemical reduction and in situ encapsulation, to produce gold nanoparticles with optimum in vivo stability and tumor specific characteristics. The interaction of mangiferin with a Au-198 gold precursor affords MGF-198AuNPs as the beta emissions of Au-198 provide unique advantages for tumor therapy while gamma rays are used for the quantitative estimation of gold within the tumors and various organs. The laminin receptor specificity of mangiferin affords specific accumulation of therapeutic payloads of this new therapeutic agent within prostate tumors (PC-3) of human prostate tumor origin induced in mice which overexpress this receptor subtype. Detailed in vivo therapeutic efficacy studies, through the intratumoral delivery of MGF-198AuNPs, show the retention of over 80% of the injected dose (ID) in prostate tumors up to 24 h. By three weeks post treatment, tumor volumes of the treated group of animals showed an over 5 fold reduction as compared to the control saline group. New opportunities for green nanotechnology and a new paradigm of using mangiferin as a tumor targeting agent in oncology for the application of MGF-198AuNPs in the treatment of cancer are discussed.

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  • IPEN-DOC 23193

    SALIBA-SILVA, ADONIS M. ; SANTOS, OLAIR dos ; CARVALHO, ELITA F.U. de ; RIELLA, HUMBERTO G. ; DURAZZO, MICHELANGELO . Determination of uranium traces in nuclear reactor IEA-R1 pool water. World Journal of Nuclear Science and Technology, v. 7, n. 3, p. 155-166, 2017. DOI: 10.4236/wjnst.2017.73014

    Abstract: IEA-R1 nuclear reactor operation has the routine to control uranium content in pool water to be in trace range below 50 μg/L. There are several routes to determine the uranium trace content in water in the literature; voltammetry has been systematically employed. In the present study, the chosen chemical determination of uranium traces used the voltammetric method known as AdCSV (adsorptive cathodic stripping voltammetry). This technique, based on mercury voltammetry, is an adequate methodology to determine uranium traces. The chloranilic acid [CAA] (2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone) is indicated as chelating agent. The redox reaction of 22 UO + with CAA is sensitive in the range of 2 < pH < 3. But pH variation imposes changing on [UO2(CAA)2] reduction potential. In this work, we present the uranium trace results for IEA-R1 reactor water, sampled after an operation routine shutdown. The uranium trace determination for IEA-R1 pool water showed content around 1 μg/L [U] with statistical significance. Therefore the IEA-R1-reactor-water purification showed to be adequate and safe.

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  • IPEN-DOC 23148

    AMATO-LOURENCO, LUIS F.; LOBO, DEBORA J.A.; GUIMARAES, ELIANE T.; MOREIRA, TIANA C.L.; CARVALHO-OLIVEIRA, REGIANI; SAIKI, MITIKO ; SALDIVA, PAULO H.N.; MAUAD, THAIS. Biomonitoring of genotoxic effects and elemental accumulation derived from air pollution in community urban gardens. Science of the Total Environment, v. 575, p. 1438-1444, 2017. DOI: 10.1016/j.scitotenv.2016.09.221

    Abstract: Urban gardening is a growing global phenomenon with a positive impact on society. Despite several associated benefits, growing vegetables in urban gardens that are localized in highly polluted areas poses questions about the safety of the produced food. Therefore, the identification of risk factors that result in possible deleterious effects to human health is important for realizing all of the benefits to society. We evaluated the use of two-biomonitoring methods in ten urban gardens of Sao Paulo city and one control site: the micronuclei frequencies for early tetrads of Tradescantia pallida (Rose) Hunt. cv. "Purpurea" Boom(hereafter, Trad-MCN) as a short-term indicator of genotoxic response and tree barks to quantify the accumulation of traffic-related chemical elements as a long-term biomarker of air pollution in urban gardens. Mature plants of Tradescantia pallida were exposed in each garden, and their inflorescences were sampled over three months. A random set of 300 early tetrads in 13 to 21 slides per garden were evaluated for micronuclei frequencies. Elemental concentrations in 428 tree barks samples from 107 different trees in the areas surrounding urban gardens were quantified using an energy dispersive X-ray fluorescence spectrometer. The frequency of Trad-MCN has a significant correlation with traffic variables and chemical elements related to road dust and tailpipe emissions deposited in tree barks. Negative associations between Trad-MCN and both the distance through traffic and the presence of vertical obstacles were observed in the community gardens. The Mn/Zn concentrations in tree barks were associated with increased Trad-MCN.

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  • IPEN-DOC 23183

    NASCIMENTO, MAURICIO S.; FRAJUCA, CARLOS; NAKAMOTO, FRANCISCO Y.; SANTOS, GIVANILDO A. dos; COUTO, ANTONIO A. . Correlação entre variáveis térmicas de solidificação, microestrutura e resistência mecânica da liga Al-10%Si-2%Cu / Correlation between solidification thermal variables, microstructure and mechanical strength of an Al-10wt%Si-2wt%Cu alloy. Revista Matéria, v. 22, n. 1, 2017. DOI: 10.1590/S1517-707620170001.0106

    Abstract: As condições operacionais impostas nos processos de fundição geram, como consequência direta, uma diversidade de estruturas de solidificação. Em geral, as propriedades mecânicas mostram-se fortemente dependentes da morfologia estrutural e da composição química. Um aço de baixo carbono foi utilizado para promover fluxo de calor unidirecional durante a solidificação e obter o arranjo da microestrutura. O objetivo deste trabalho é pesquisar a influência das variáveis térmicas de solidificação na microestrutura da liga Al-10%Si- 2%Cu e na sua resistência mecânica. Resultados experimentais incluem os espaçamentos dendríticos primários (EDP), velocidade de deslocamento da isoterma liquidus (VL), taxa de resfriamento (TR) e limites de resistência à tração (LRT) e de escoamento (LE). Estruturas dendríticas mais grosseiras tendem a diminuir a resistência à tração e ao escoamento na liga em estudo.

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  • IPEN-DOC 23167

    FURUKAWA, CASSIA Y. ; FUKUMORI, NEUZA T.O. ; MATSUDA, MARGARETH M.N. . Avaliação da condição de transporte na estabilidade do bicisato (99m Tc) / Evaluation of the transportation condition on the stability of Technetium Tc 99m bicisate. Revista Brasileira de Farmácia, v. 98, n. 1, p. 1864-1875, 2017.

    Abstract: O radiofármaco de bicisato (99m Tc) é utilizado em cintilografia cerebral por SPECT para obtenção de imagens do fluxo sanguíneo cerebral em pacientes com anomalias do sistema nervoso central, tais como epilepsia, demência, acidente vascular cerebral e traumas. O objetivo deste trabalho foi avaliar a pureza radioquímica do bicisato (99m Tc) após simular uma condição de estresse no transporte do ECD-TEC (IPEN), colocando o reagente liofilizado por 48 horas em 40 oC e 75% umidade relativa. Foi feita a comparação da pureza radioquímica obtida com frascos do reagente liofilizado ECD-TEC mantidos por três meses em temperatura de 2 a 8 oC, com frascos colocados por 48 horas em câmara climática a 40 oC e 75% de umidade relativa, e com frascos mantidos sem controle de temperatura, e que foram marcados com eluato de pertecnetato de sódio. Os resultados de pureza radioquímica maiores que o limite especificado pelas farmacopeias em amostras analisadas imediatamente após a fabricação e em amostras submetidas às diferentes condições de temperatura e umidade indicaram que não houve alteração na estabilidade do produto, quando respeitados os cuidados especiais de marcação descritos na bula, recomendados pelo fabricante.

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  • IPEN-DOC 23141

    PORTO, KARINA M.B.G.; NAPOLITANO, CELIA M. ; BORRELY, SUELI I. . Gamma radiation effects in packaging for sterilization of health products and their constituents paper and plastic film. Radiation Physics and Chemistry, p. 1-6, 2017. DOI: 10.1016/j.radphyschem.2016.12.019

    Abstract: The integrity of materials containing packaging (natural or synthetic polymers) is essential to keep the aseptic condition of commercialized products (health care products, food and pharmaceuticals). The objective of this paper was to study gamma radiation effects (25 kGy, 40 kGy and 50 kGy) on the main properties of paper and multilayer films (polyester and polyethylene). Paper and multilayer films are components of packaging (pouches) for radiation sterilization containing medical equipment or products. Paper was the more radiation sensitive among the studied materials and radiation effects were more pronounced at brightness, pH, tearing resistance, bursting strength and tensile strength. Concerning plastic film, no pinholes were induced by radiation and the effects on the tensile strength were not significant. Although the seal strength packaging (pouches) decreased according to increasing dose, the sealing integrity was preserved.

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  • IPEN-DOC 23198

    SANTOS, FELIPE A.; GALEANO, DIEGO C.; SANTOS, WILLIAM S. ; SILVA, ADEMIR X.; SOUZA, SUSANA O.; CARVALHO JUNIOR, ALBERICO B.. Evaluation of equivalent and effective dose by KAP for patient and orthopedic surgeon in vertebral compression fracture surgery. Radiation Physics and Chemistry, v. 132, p. 30-40, 2017. DOI: 10.1016/j.radphyschem.2016.11.011

    Abstract: Clinical scenarios were virtually modeled to estimate both the equivalent and effective doses normalized by KAP (Kerma Area Product) to vertebra compression fracture surgery in patient and surgeon. This surgery is known as kyphoplasty and involves the use of X-ray equipment, the C-arm, which provides real-time images to assist the surgeon in conducting instruments inserted into the patient and in the delivery of surgical cement into the fractured vertebra. The radiation transport code used was MCNPX (Monte Carlo N-Particle eXtended) and a pair of UFHADM (University of Florida Hybrid ADult Male) virtual phantoms. The developed scenarios allowed us to calculate a set of equivalent dose (H-T) and effective dose (E) for patients and surgeons. In additional, the same scenario was calculated KAP in the tube output and was used for calculating conversion coefficients (E/KAP and H-T/KAP). From the knowledge of the experimental values of KAP and the results presented in this study, it is possible to estimate absolute values of effective doses for different exposure conditions. In this work, we developed scenarios with and without the surgical table with the purpose of comparison with the existing data in the literature. The absence of the bed in the scenario promoted a percentage absolute difference of 56% in the patient effective doses in relation to scenarios calculated with a bed. Regarding the surgeon, the use of the personal protective equipment (PPE) reduces between 75% and 79% the effective dose and the use of the under table shield (UTS) reduces the effective dose of between 3% and 7%. All these variations emphasize the importance of the elaboration of virtual scenarios that approach the actual clinical conditions generating E/KAP and H-T/KAP closer to the actual values.

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  • 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.

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  • IPEN-DOC 23162

    DURAZZO, M. ; SOUZA, J.A.B. ; CARVALHO, E.F.U. de ; RIELLA, H.G. . Effect of porosity on the manufacturing of U3O8-Al dispersion fuel plates. Progress in Nuclear Energy, v. 99, p. 49-58, 2017. DOI: 10.1016/j.pnucene.2017.05.001

    Abstract: The pore volume present in the starting fuel meat of dispersion fuel plates influences the behavior of its deformation during the fuel plate fabrication by rolling to a great extent. This study was carried out to investigate the influence of pore content in the starting fuel meat on the manufacturing of aluminum-base dispersion fuel plates. Factors that affect the residual porosity present in the meat of the fuel plate were investigated. Results showed that the residual pore volume of aluminum-base dispersion-type U3O8-Al fuel plates depends on the characteristics of the starting fuel meat, which is fabricated by pressing. The residual pore volume depends on the U3O8 concentration. For a particular U3O8 concentration, the rolling process establishes a constant pore volume, which is called equilibrium porosity. The equilibrium porosity is insensitive to the initial pore volume present in the starting fuel meat. The research showed that fuel meat integrity was greatly influenced by the initial porosity of the fuel meat. U3O8-Al dispersion fuel plates were successfully fabricated with uranium loading above 3.0 gU/cm(3). This uranium loading is equivalent to the one used in the U3Si2-Al dispersion fuel, currently operating at the lEA-R1 research reactor of the Nuclear and Energy Research Institute - IPEN/CNEN-SP. The U3O8-Al dispersion fuel can substitute the silicide fuel with advantages such as lower price and simpler manufacturing process.

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  • IPEN-DOC 23168

    GALANTE, RAQUEL; REDIGUIERI, CAROLINA F.; KIKUCHI, IRENE S.; VASQUEZ, PABLO A.S. ; COLACO, ROGERIO; SERRO, ANA P.; PINTO, TEREZINHA J.A.. About the sterilization of chitosan hydrogel nanoparticles. Plos One, v. 11, n. 12, 2016. DOI: 10.1371/journal.pone.0168862

    Abstract: In the last years, nanostructured biomaterials have raised a great interest as platforms for delivery of drugs, genes, imaging agents and for tissue engineering applications. In particular, hydrogel nanoparticles (HNP) associate the distinctive features of hydrogels (high water uptake capacity, biocompatibility) with the advantages of being possible to tailor its physicochemical properties at nano-scale to increase solubility, immunocompatibility and cellular uptake. In order to be safe, HNP for biomedical applications, such as injectable or ophthalmic formulations, must be sterile. Literature is very scarce with respect to sterilization effects on nanostructured systems, and even more in what concerns HNP. This work aims to evaluate the effect and effectiveness of different sterilization methods on chitosan (CS) hydrogel nanoparticles. In addition to conventional methods (steam autoclave and gamma irradiation), a recent ozone-based method of sterilization was also tested. A model chitosan-tripolyphosphate (TPP) hydrogel nanoparticles (CS-HNP), with a broad spectrum of possible applications was produced and sterilized in the absence and in the presence of protective sugars (glucose and mannitol). Properties like size, zeta potential, absorbance, morphology, chemical structure and cytotoxicity were evaluated. It was found that the CS-HNP degrade by autoclaving and that sugars have no protective effect. Concerning gamma irradiation, the formation of agglomerates was observed, compromising the suspension stability. However, the nanoparticles resistance increases considerably in the presence of the sugars. Ozone sterilization did not lead to significant physical adverse effects, however, slight toxicity signs were observed, contrarily to gamma irradiation where no detectable changes on cells were found. Ozonation in the presence of sugars avoided cytotoxicity. Nevertheless, some chemical alterations were observed in the nanoparticles.

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  • IPEN-DOC 23169

    GIMENEZ-ALVENTOSA, VINCENT; ANTUNES, PAULA C.G. ; VIJANDE, JAVIER; BALLESTER, FACUNDO; PEREZ-CALATAYUD, JOSE; ANDREO, PEDRO. Collision-kerma conversion between dose-to-tissue and dose-to-water by photon energy-fluence corrections in low-energy brachytherapy. Physics in Medicine & Biology, v. 62, n. 1, p. 146-164, 2017. DOI: 10.1088/1361-6560/aa4f6a

    Abstract: The AAPM TG-43 brachytherapy dosimetry formalism, introduced in 1995, has become a standard for brachytherapy dosimetry worldwide; it implicitly assumes that charged-particle equilibrium (CPE) exists for the determination of absorbed dose to water at different locations, except in the vicinity of the source capsule. Subsequent dosimetry developments, based on Monte Carlo calculations or analytical solutions of transport equations, do not rely on the CPE assumption and determine directly the dose to different tissues. At the time of relating dose to tissue and dose to water, or vice versa, it is usually assumed that the photon fluence in water and in tissues are practically identical, so that the absorbed dose in the two media can be related by their ratio of mass energy-absorption coefficients. In this work, an efficient way to correlate absorbed dose to water and absorbed dose to tissue in brachytherapy calculations at clinically relevant distances for low-energy photon emitting seeds is proposed. A correction is introduced that is based on the ratio of the water-to-tissue photon energy-fluences. State-of-the art Monte Carlo calculations are used to score photon fluence differential in energy in water and in various human tissues (muscle, adipose and bone), which in all cases include a realistic modelling of low-energy brachytherapy sources in order to benchmark the formalism proposed. The energy-fluence based corrections given in this work are able to correlate absorbed dose to tissue and absorbed dose to water with an accuracy better than 0.5% in the most critical cases (e.g. bone tissue).

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  • IPEN-DOC 23216

    ZAGATTO, V.A.B.; LUBIAN, J.; GASQUES, L.R.; ALVAREZ, M.A.G.; CHAMON, L.C.; OLIVEIRA, J.R.B.; ALCANTARA-NUNEZ, J.A.; MEDINA, N.H.; SCARDUELLI, V.; FREITAS, A.; PADRON, I.; ROSSI JUNIOR, E.S.; SHORTO, J.M.B. . Elastic scattering, inelastic excitation, and neutron transfer for 7Li + 120Sn at energies around the Coulomb barrier. Physical Review C, v. 95, n. 6, p. 064614-1 - 064614-8, 2017. DOI: 10.1103/PhysRevC.95.064614

    Abstract: Experimental angular distributions for the Li-7 + Sn-120 elastic and inelastic (projectile and target excitations) scattering, and for the neutron stripping reaction, have been obtained at E-LAB = 20, 22, 24, and 26 MeV, covering an energy range around the Coulomb barrier (V-B((LAB)) approximate to 21.4 MeV). Coupled channel and coupled reaction channel calculations were performed and both describe satisfactorily the experimental data sets. The 1/2(-) state Li-7 inelastic excitation (using a rotational model), as well as the projectile coupling to the continuum (alpha plus a tritium particle) play a fundamental role on the proper description of elastic, inelastic, and transfer channels. Couplings to the one-neutron stripping channel do not significantly affect the theoretical elastic scattering angular distributions. The spectroscopic amplitudes of the transfer channel were obtained through a shell model calculation. The theoretical angular distributions for the one-neutron stripping reaction agreed with the experimental data.

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  • IPEN-DOC 23204

    SHRIVASTAVA, NAVADEEP; KHAN, L.U.; VARGAS, J.M.; OSPINA, CARLOS; COAQUIRA, J.A.Q.; ZOPPELLARO, GIORGIO; BRITO, H.F.; JAVED, YASIR; SHUKLA, D.K.; FELINTO, M.C.F.C. ; SHARMA, SURENDER K.. Efficient multicolor tunability of ultrasmall ternary-doped LaF3 nanoparticles: energy conversion and magnetic behavior. Physical Chemistry Chemical Physics, v. 19, n. 28, p. 18660-18670, 2017. DOI: 10.1039/c7cp02235b

    Abstract: Luminescence-tunable multicolored LaF3: xCe(3+), xGd(3+), yEu(3+) (x = 5; y = 1, 5, 10, and 15 mol%) nanoparticles have been synthesized via a low cost polyol method. Powder X-ray diffraction and high-resolution transmission electron microscopy studies confirm the hexagonal phase of the LaF3: xCe(3+), xGd(3+), yEu(3+) nanophosphors with average sizes (oval shape) ranging from 5 to 7 nm. Energy-dispersive X-ray spectroscopy analyses show the uniform distribution of Ce3+, Gd3+, and Eu3+ dopants in the LaF3 host matrix. The photoluminescence spectra and electron paramagnetic resonance measurements guarantee the presence of Eu2+, corroborated through DC susceptibility measurements of the samples displaying paramagnetic behavior at 300 K, whereas weak ferromagnetic ordering is shown at 2 K. The non-radiative energy transfer processes from the 4f(F-2(5/2)) -> 5d state (Ce3+) to the intraconfigurational 4f excited levels of rare earth ions and simultaneous emissions in the visible region from the 4f(6)5d(1) (Eu2+) and D-5(0) (Eu3+) emitting levels, leading to overlapped broad and narrow emission bands, have been proclaimed. The energy transfer mechanism proposes involvement of the Gd3+ ion sub-lattice as the bridge and finally trapping by Eu2+/3+, upon excitation of the Ce3+ ion. The calculation of experimental intensity parameters (Omega(2,4)) has been discussed and the highest emission quantum efficiency (eta = 85%) of the Eu3+ ion for the y = 10 mol% sample is reported. The advantageous existence of the Eu2+/Eu3+ ratio along with variously doped nanomaterials described in this work, results in tunable emission color in the blue-white-red regions, highlighting the potential application of the samples in solid-state lighting devices, scintillation devices, and multiplex detection.

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  • IPEN-DOC 23188

    PINTO, NATHALI C.; POMERANTZEFF, PABLO M.A.; DEANA, ALESSANDRO; ZEZELL, DENISE ; BENETTI, CAROLINA ; AIELLO, VERA D.; LOPES, LUCIANA A.; JATENE, FABIO B.; CHAVANTES, M.C.. Descriptive analysis of in vitro cutting of swine mitral cusps: comparison of high-power laser and scalpel blade cutting techniques. Photomedicine and Laser Surgery, v. 35, n. 2, p. 87-91, 2017. DOI: 10.1089/pho.2015.3993

    Abstract: Background and objectives: The most common injury to the heart valve with rheumatic involvement is mitral stenosis, which is the reason for a big number of cardiac operations in Brazil. Commissurotomy is the traditional technique that is still widely used for this condition, although late postoperative restenosis is concerning. This study's purpose was to compare the histological findings of porcine cusp mitral valves treated in vitro with commissurotomy with a scalpel blade to those treated with high-power laser (HPL) cutting, using appropriate staining techniques. Materials and methods: Five mitral valves from healthy swine were randomly divided into two groups: Cusp group (G1), cut with a scalpel blade (n = 5), and Cusp group (G2), cut with a laser (n = 5). G2 cusps were treated using a diode laser (lambda = 980 nm, power = 9.0 W, time = 12 sec, irradiance = 5625 W/cm(2), and energy = 108 J). Results: In G1, no histological change was observed in tissue. A hyaline basophilic aspect was focally observed in G2, along with a dark red color on the edges and areas of lower birefringence, when stained with hematoxylin-eosin, Masson's trichrome, and Sirius red. Further, the mean distances from the cutting edge in cusps submitted to laser application and stained with Masson's trichrome and Sirius red were 416.7 and 778.6 mu m, respectively, never overcoming 1mm in length. Conclusions: Thermal changes were unique in the group submitted to HPL and not observed in the cusp group cut with a scalpel blade. The mean distance of the cusps' collagen injury from the cutting edge was less than 1mm with laser treatment. Additional studies are needed to establish the histological evolution of the laser cutting and to answer whether laser cutting may avoid valvular restenosis better than blade cutting.

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  • IPEN-DOC 23175

    LEAL, CINTIA R.L.; ALVARENGA, LETICIA H.; OLIVEIRA-SILVA, TAMIRES; KATO, ILKA T.; GODOY-MIRANDA, BIANCA; BUSSADORI, SANDRA K.; RIBEIRO, MARTHA S. ; PRATES, RENATO A.. Antimicrobial photodynamic therapy on Streptococcus mutans is altered by glucose in the presence of methylene blue and red LED. Photodiagnosis and Photodynamic Therapy, v. 19, p. 1-4, 2017. DOI: 10.1016/j.pdpdt.2017.04.004

    Abstract: Background: Dental caries are a multifactorial disease that progressively produces tooth destruction as a result of bacterial colonization of enamel surface, especially Streptococcus mutans. The objective of this work was to investigate the role of glucose in antimicrobial photodynamic therapy (aPDT) on S. mutans. Methods: S. mutans ATCC 25175 were cultured on microaerophilia at 37 °C for 48 h, and we tested aPDT in the presence of 50 mM glucose. Bacterial suspension was used to investigate aPDT with 100 μM methylene blue (MB) under LED emitting radiation at ʎ =660 nm and parameters as following (P =473 mW; I =166.8 mW/ cm2, and doses of 5, 10 and 20 J/cm2). A seventy-two hours biofilm was grown on 96 flat buttoned well-plate and irradiation was performed from 10 to 80 J/cm2 at similar conditions. Results: There was no dark toxicity nor bacterial death regarding LED irradiation on suspension and on biofilm. Nevertheless, aPDT presented expressive bacterial inactivation following 1 and 2 min of irradiation on cell suspension. On the other hand, there was no inactivation in the presence of glucose under the same conditions. Biofilm was completely inactivated by MB-mediated aPDT after 6 min of irradiation. However, the presence of glucose delayed the complete inactivation of the biofilm. Conclusion: The presence of glucose in the suspension drastically delayed the effect of aPDT on S. mutans and this effect is more pronounced in bacterial suspension than on biofilm.

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  • IPEN-DOC 23152

    BERECZKI, ALLAN ; WETTER, NIKLAUS U. . 100W continuous linearly polarized, high beam quality output from standard side-pumped Nd:YAG laser modules. Optics and Laser Technology, v. 96, p. 271-275, 2017. DOI: 10.1016/j.optlastec.2017.05.020

    Abstract: Dynamically stable operation with joined stability zones of a linearly polarized resonator is shown for a laser containing two diode side-pumped Nd:YAG rods. The unpolarized resonator generated 115W of output. When polarized by a Brewster plate, it reached 100.5W of output power at a beam quality M2 < 2. Best measured beam quality was of 1.1 and 1.3 in the x and y directions respectively, with 76W of 95% polarized output. The output power achieved is, to our knowledge, the highest reported for continuous polarized, fundamental-mode lasers using standard side-pumped Nd:YAG modules.

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  • IPEN-DOC 23170

    GOMES, LAERCIO ; FORTIN, VINCENT; BERNIER, MARTIN; MAES, FREDERIC; VALLEE, REAL; POULAIN, SAMUEL; POULAIN, MARCEL; JACKSON, STUART D.. Excited state absorption and energy transfer in Ho3+-doped indium fluoride glass. Optical Materials, v. 66, p. 519-526, 2017. DOI: 10.1016/j.optmat.2017.02.048

    Abstract: This investigation examines in detail the rates of energy transfer relevant to the I-5(6) -> I-5(6) transition (at 3930 nm) in Ho3+-doped InF3 glass as a function of the Ho3+ concentration. The decay times, branching ratios and rate parameters for energy transfer were measured in this investigation for Ho3+ (x)-doped InF3 glass with x = 2, 4 and 10 mol.% and they were used as the input parameters for a rate equation analysis. Excited state absorption (ESA) initiating from the lower laser level is included in the study. Numerical simulation of CW laser emission at 3.9 pm was performed using two pump wavelengths, one for upper laser level excitation (i.e., I-5(8) -> (5)1(5) = lambda(P1)) and the other for lower laser level de-excitation (i.e., I-5(6) -> S-5(2) = lambda(P2)). The pump wavelength lambda(P2) = 962 nm was chosen based on the measurements of ESA and the application of the McCumber method. Critically, the estimated ESA cross section at lambda(P2) = 962 nm (sigma(ESA) = 7.1 x 10(-21) cm(2)) is approximately sixteen times larger than ground state (I-5(8)) absorption cross section (sigma(GSA) = 4.3 x 10(-22) cm(2)) and ESA does not overlap with any ground state absorption process. Our calculations suggest that even for high Ho3+ concentration in which cross relaxation has been shown in a previous study to quench the I-5(5) level, ESA is nevertheless strong enough to allow a sufficient population inversion required for practical CW emission.

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  • IPEN-DOC 23199

    SANTOS, SOFIA N. dos ; SHELDON, HELEN; PEREIRA, JONATHAS X.; PALUCH, CHRISTOPHER; BRIDGES, ESTHER M.; EL-CHEIKH, MARCIA C.; HARRIS, ADRIAN L.; BERNARDES, EMERSON S. . Galectin-3 acts as an angiogenic switch to induce tumor angiogenesis via Jagged-1/Notch activation. Oncotarget, v. 8, n. 30, p. 49484-49501, 2017. DOI: 10.18632/oncotarget.17718

    Abstract: Angiogenesis is a coordinated process tightly regulated by the balance between Delta-like-4 (DLL4) and Jagged-1 (JAG1) in endothelial cells. Here we show that galectin-3 (gal-3), a glycan-binding protein secreted by cancer cells under hypoxic conditions, triggers sprouting angiogenesis, assisted by hypoxic changes in the glycosylation status of endothelial cells that enhance binding to gal-3. Galectin-3' s proangiogenic functions were found to be predominantly dependent on the Notch ligand JAG1. Differential direct binding to JAG1 was shown by surface plasmon resonance assay. Upon binding to Notch ligands, gal-3 preferentially increased JAG1 protein half-life over DLL4 and preferentially activated JAG1/Notch-1 signaling in endothelial cells. JAG1 overexpression in Lewis lung carcinoma cells accelerated tumor growth in vivo, but this effect was prevented in Lgals3(-/-) mice. Our findings establish gal-3 as a molecular regulator of the JAG1/Notch-1 signaling pathway and have direct implications for the development of strategies aimed at controlling tumor angiogenesis.

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  • IPEN-DOC 23153

    BOMFIM, PAMELA K.S.; CRUZ, ISRAEL A.; FREDERICCI, CATIA; NEVES, MAURICIO D.M. . Production and characterization of porous titanium applied in biomaterial. Materials Science Forum, v. 899, p. 179-184, 2017. DOI: 10.4028/www.scientific.net/MSF.899.179

    Abstract: The development of materials with a porous titanium surface has been widely studied in the field of biomaterials due to the excellent biocompatibility, high corrosion resistance and combination of high strength with low density. Another relevant fact is that porosity allows bone tissue growth. However, the high reactivity in liquid state ends up hindering titanium fusion, so an alternative is the powder metallurgy (PM).The aim of this work was to produce porous titanium samples by conventional PM. Porous samples was characterized by porosity and microstructure (optical microscopy - OP and scanning electron microscopy SEM), crystaline phase (X-ray diffraction –XRD), mechanical properties (three point bending test) and cytotoxic test. The results showed the presence of alpha phase, a decrease in the elasticity modulus, increase in average pore size and samples exhibited no toxic effects.

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  • IPEN-DOC 23179

    MERGULHAO, MARCELLO V. ; PODESTA, CARLOS E.; NEVES, MAURICIO D.M. das . Mechanical properties and microstructural characterization of Cobalt-Chromium (CoCr) obtained by casting and Selective Laser Melting (SLM). Materials Science Forum, v. 899, p. 534-539, 2017. DOI: 10.4028/www.scientific.net/MSF.899.534

    Abstract: The aim of this study is the consolidation of Cobalt-Chromium (CoCr) alloy powder using the additive manufacturing - selective laser melting (SLM) and the investment casting techniques. The research of this study has been applied to their biomaterial applied to development of prosthesis and dental implants. The gas atomized powder are spherical (mean diameter equal to 42,74 μm) and was analyzed by their physical and chemical properties. The microstructure of the powder and specimens was evaluated using optical microscope (OM) and scanning electron microscope with energy-dispersed X-ray spectroscopy (SEM-EDS). The mechanical properties were evaluated of standard samples using a tensile (yield strength, maximum tensile, rupture tensile and elongation), three point bending (transverse rupture strength) and micro hardness tests. The mechanical results indicate higher values for the SLM than casting specimens. The micrographs revealed a characteristic morphology of laser been used in the SLM technique and the dendrites in the casting technique. The microstructure of samples made by SLM is thinner than the samples obtained in the cast.

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  • IPEN-DOC 23180

    MERGULHAO, MARCELLO V. ; PODESTA, CARLOS E.; NEVES, MAURICIO D.M. das . Valuation of mechanical properties and microstructural characterization of ASTM F75 Co-Cr alloy obtained by Selective Laser Melting (SLM) and casting techniques. Materials Science Forum, v. 899, p. 323-328, 2017. DOI: 10.4028/www.scientific.net/MSF.899.323

    Abstract: Advances in processes using the powder metallurgy techniques are making this technology competitive compared to the other traditional manufacturing processes, especially in medicine area. The additive rapid prototyping technique – selective laser melting (SLM) was applied in a biomaterial of CoCrMoFe alloy (ASTM F75), to study the mechanical properties and microstructural characterization in comparison between the conventional technique – casting. The gas atomized powder was investigated by their physical (as apparent density, bulk density and flow rate) and the chemical properties. The powder was analyzed using scanning electron microscope with energy-dispersed X-ray spectroscopy (SEM-EDS) and X-ray fluorescence. Specimens of standard samples were manufactured using these techniques to evaluate the mechanical properties as uniaxial tensile (yield strength, rupture tensile and elongation), transverse rupture strength and the micro hardness. The mechanical properties showed higher values in the SLM specimens than the casting specimens. Before the mechanical tests the specimens were examined using optical microscope (OM) and SEM-EDS. The micrographs revealed a microstructure with finer morphology in the SLM technique and the dendrites in the casting technique.

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  • IPEN-DOC 23149

    BARATELA, FERNANDO J.C. ; HIGA, OLGA Z. ; PASSOS, ESDRAS D. dos; QUEIROZ, ALVARO A.A. de. Fabrication of electrospun HPGL scaffolds via glycidyl methacrylate cross-linker: Morphology, mechanical and biological properties. Materials Science and Engineering C, v. 73, p. 72-79, 2017. DOI: 10.1016/j.msec.2016.12.033

    Abstract: Electrospinning is a suitable method to produce scaffolds composed of nanoscale to microscale fibers, which are comparable to the extracellular matrix (ECM). Hyperbranched polyglycerol (HPGL) is a highly biocompatible polyether polyol potentially useful for the design of fibrous scaffolds mimicking the ECM architecture. However, scaffolds developed from HPGL have poor mechanical properties and morphological stability in the aqueous environments required for tissue engineering applications. This work reports the production of stable electrospun HPGL scaffolds (EHPGLS) using glycidyl methacrylate (GMA) as cross-linker to enhance the water stability and mechanical property of electrospun HPGL The diameter and morphology of the produced EHPGLS were analyzed by scanning electron microscopy (SEM). It was observed that electrical fields in the range of 0.2 kV.cm(-1) to 1.0 kV.cm(-1) decrease the average fiber diameter of EHPGLS. The increase in porosity of EHPGLS with GMA concentration indicates the in situ formation of a heterogeneous structure resultant from the phase separation during crosslinking of HPGL by GMA. EHPGLS containing 20% (w/w) GMA concentration possessed highest tensile strength (295.4 +/- 1132 kPa), which is approximately 58 times higher than that of non-crosslinked EHPGLS (5.1 +/- 2.12 kPa). The MTS cell viability results showed that the EHPGLS have no significant cytotoxicity effect on Chinese hamster ovary (CHO-K1) cells. Scanning electron microscopy (SEM) indicates that the cultured BALB/3T3 fibroblasts cells were able to keep contact each other's, thus forming a homogeneous monolayer on the internal surface of the EHPGLS.

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  • IPEN-DOC 23191

    RIBEIRO, CHARLENE A.; MARTINS, MARCOS V.S. ; BRESSIANI, ANA H. ; BRESSIANI, JOSE C. ; LEYVA, MARIA E.; QUEIROZ, ALVARO A.A. de. Electrochemical preparation and characterization of PNIPAM-HAp scaffolds for bone tissue engineering. Materials Science and Engineering C, v. 81, p. 156-166, 2017. DOI: 10.1016/j.msec.2017.07.048

    Abstract: In the last decade, a variety of methods for fabrication of three-dimensional biomimetic scaffolds based on hydrogels have been developed for tissue engineering. However, many methods require the use of catalysts which compromises the biocompatibility of the scaffolds. The electrochemical polymerization (ECP) of acrylic monomers has received an increased attention in recent years due to its versatility in the production of highly biocompatible coatings for the electrodes used in medical devices. The main aim of this work was the use of ECP as scaffold fabrication technique to produce highly porous poly(N-isopropylacrylamide) (PNIPAM)/hydroxyapatite (HAp) composite for bone tissue regeneration. The prepared PNIPAM-HAp porous scaffolds were characterized by SEM, FTIR, water swelling, porosity measurements and X-ray diffraction (XRD) techniques. FTIR indicates that ECP promotes a successful conversion of NIPAM to PNIPAM. The water swelling and porosity were shown to be controlled by the HAp content in PNIPAM-HAp scaffolds. The PNIPAM-HAp scaffolds exhibited no cytotoxicity to MG63 cells, showing that ECP are potentially useful for the production of PNIPAMHAp scaffolds. To address the osteomyelitis, a significant complication in orthopedic surgeries, PNIPAM-HAp scaffolds were loaded with the antibiotic oxacillin. The oxacillin release and the bacterial killing activity of the released oxacillin from PNIPAM-HAp against S. aureus and P. aeruginosa were demonstrated. These observations demonstrate that ECP are promising technique for the production of non-toxic, biocompatible PNIPAM-HAp scaffolds for tissue engineering.

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  • IPEN-DOC 23194

    SALLES, TAIS H.C.; SENDYK, DANIEL I.; OLIVEIRA, NATACHA K. de; MACHADO, DAISY; LANCELLOTTI, MARCELO; DEBONI, MARIA C.Z.; KIANG, CHANG T.; DAVILA, MARCOS A.. In vitro and in vivo evaluation of electrospun membranes of poly (ε-caprolactone) and poly (rotaxane). Materials Science and Engineering C, v. 77, p. 912-919, 2017. DOI: 10.1016/j.msec.2017.03.190

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  • IPEN-DOC 23185

    OLIANI, WASHINGTON L. ; PARRA, DUCLERC F. ; KOMATSU, LUIZ G.H. ; LINCOPAN, NILTON; RANGARI, VIJAYA K.; LUGAO, ADEMAR B. . Fabrication of polypropylene/silver nanocomposites for biocidal applications. Materials Science and Engineering C, v. 75, p. 845-853, 2017. DOI: 10.1016/j.msec.2017.02.109

    Abstract: This paper presents a study on biocidal effect of polymer nanocomposite films of gamma irradiated polypropylene (PP) and silver nanoparticles. The modified polypropylene was obtained from isotactic polypropylene (iPP) in pellets form by irradiation with gamma rays in the presence of acetylene. A new morphology with long chain branching of PP and distinct rheology is obtained by this process. The blend of 50/50 wt neat PP and PP modified by gamma radiation were further mixed using a twin screw extruder. The AgNPs were infused into this polymer blend at different concentrations of: 0.1%; 0.25%; 05%; 1.0%; 1.0% (PVP), 2.0% and 4.0% by wt%. These polymer nanocomposites were characterized by Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM), cytotoxicity test and Kirby-Bauer disk diffusion techniques. The bactericidal effect of Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) were assessed in detail.

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  • IPEN-DOC 23143

    COSTA E SILVA, DANILO L. ; KASSAB, LUCIANA R.P.; MARTINELLI, JOSE R. ; SANTOS, ANTONIO D. dos; RIBEIRO, SIDNEY J.L.; SANTOS, MOLIRIA V. dos. Characterization of thin carbon films produced by the magnetron sputtering technique. Materials Research: Ibero-american Journal of Materials, v. 19, n. 3, p. 669-672, 2016. DOI: 10.1590/1980-5373-MR-2015-0058

    Abstract: Thin carbon films containing both amorphous and crystalline structures were produced by RF magnetron sputtering. The depositions of the carbon films were performed on Co buffer layers previously deposited on c-plane (0001) sapphire substrates. The thin carbon films were characterized by high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDS), and field emission scanning electron microscope (FEG-SEM). The Raman spectra confirmed the presence of amorphous and crystalline structures by the existence of an intense D band separated from the G band, indicating early stages of crystallization. The interplanar distance corresponding to the graphite structures was determined by using HRTEM micrographs.

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  • IPEN-DOC 00000

    PIERETTI, EURICO F. . Biomêcanica aplicada na avaliação de propriedades de implantes ortopédicos metálicos tratados por feixe laser / Applied biomechanics to evaluate the properties of laser beam treated orthopedic implants. 2016. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 204 p. Orientador: Maurício David Martins das Neves.

    Abstract: A marcação por feixe laser em superfícies é utilizada para assegurar a identificação e a rastreabilidade em biomateriais. A texturização via feixe laser confere maior aderência às superfícies dos dispositivos médicos implantáveis. Este trabalho teve o objetivo de avaliar o comportamento da superfície do aço inoxidável austenítico ABNT NBR ISO 5832-1 submetido à marcação e texturização com feixe laser de fibra óptica, alterando-se a frequência dos pulsos; frente ao seu comportamento biomecânico, por meio de: ensaios de resistência à tração, fadiga e desgaste; verificar a susceptibilidade à corrosão localizada, por ensaios eletroquímicos em solução que simula os fluidos corpóreos; e caracterizar a sua microestrutura. Os tratamentos alteraram a rugosidade e a dureza dos biomateriais em função do aumento da frequência dos pulsos. A microestrutura e composição química das superfícies sofreram mudanças que afetaram diretamente a camada passiva dos aços inoxidáveis. Este efeito foi comprovado com o uso de SVET, XPS e caracterização de propriedades eletrônicas do filme passivo. Os dois tipos de tratamentos implicaram em aumento de susceptibilidade magnética das superfícies. Os parâmetros utilizados para as marcações e texturizações não causaram diminuição na viabilidade celular, de modo que não apresentou citotoxicidade mesmo após incubação prolongada. Este biomaterial mostrou-se adequado perante os ensaios biomecânicos, uma vez que os tratamentos a laser, nas condições utilizadas, não induziram a formação de tensões superficiais de magnitude capaz de levar à fratura por fadiga, indicando vida em fadiga infinita; tampouco se pôde relacionar a região de fratura por tração com as marcações a laser. O volume de desgaste diminuiu em função do aumento da dureza produzido pela elevação da frequência do pulso nas texturizações. O caráter visual das marcações e texturizações por feixe laser foi assegurado após a maioria dos ensaios realizados.

    Palavras-Chave: implants; skeleton; medical surveillance; surface coating; surface treatments; surface forces; electrochemical coating; body fluids; stainless steels; tensile properties; fatigue; tribology; wear; corrosion; biochemistry; laser beam machining; x-ray diffraction; films; neutron activation analysis; scanning electron microscopy; standardization; comparative evaluations

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  • IPEN-DOC 23020

    BAPTISTA, ALESSANDRA . Influência da fase de crescimento celular na ação fotodinâmica: avaliação morfológica, mecânica e bioquímica, em células de Candida albicans / Influence of the cell growth phase on photodynamic action: morphological, mechanical and biochemical evaluation in cells of Candida albicans. 2015. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 121 p. Orientador: Martha Simões Ribeiro.

    Abstract: Estudos têm demonstrado o potencial da terapia fotodinâmica antimicrobiana (aPDT) na inativação de diferentes células microbianas. No geral, são três as fases de crescimento dos microrganismos: fase lag, exponencial e estacionária. Os objetivos deste estudo foram avaliar a susceptibilidade de células de Candida albicans em diferentes fases de crescimento, submetidas à aPDT, associando azul de metileno (50 μM) e luz de emissão vermelha (λ= 660 nm) e investigar alterações morfológicas, mecânicas e bioquímicas, antes e depois da aPDT, por microscopia eletrônica de varredura, de força atômica e por espectroscopia no infravermelho por transformada de Fourier. Os resultados obtidos sugerem que, em parâmetros letais, células em fase estacionária de crescimento (48 h) são menos susceptíveis à aPDT, quando comparadas àquelas em fases lag (6 h) e ex-ponencial (24 h) de crescimento. Entretanto, em parâmetros subletais, células de 6 h e 48 h mostraram a mesma susceptibilidade à aPDT. Em sequência, os experimentos foram realizados em parâmetros considerados subletais para células crescidas por 6 e 48 h. A avaliação morfológica mostrou menor quantidade de matriz extracelular em células de 6 h comparada àquelas de 48 h. A espectroscopia de força atômica mostrou que células em fase lag perderam a rigidez após a aPDT, enquanto que células em fase estacionária mostraram comportamento in-verso. Ainda, células de 48 h diminuíram sua adesividade após a aPDT, enquanto que células de 6 h e 24 h tornaram-se mais adesivas. Os resultados bioquímicos revelaram que as diferenças mais significativas entre as células fúngicas de 6 h e 48 h ocorreram na região de DNA e carboidratos. A aPDT promoveu mais alterações bioquímicas na região de DNA e carboidratos em células de 6 h e em lipídios e ácidos graxos em células de 48 h. Nossos resultados indicam que a fase de crescimento celular desempenha papel importante no sítio de ação da aPDT em células de C. albicans.

    Palavras-Chave: photochemistry; toxicity; animal cells; morphological changes; histological techniques; biochemistry; candida; yeasts; antimicrobial agentes; therapy; scanning electron microscopy; fourier transformation; infrared spectra; atomic force microscopy; dna; carbohydrates; lipids; fatty acids; comparative evaluations

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  • IPEN-DOC 23019

    AMARAL, PRISCILA O. . Caracterização química dos neonicotinóides em águas superficiais via cromatografia liquída de alta eficiência acoplada a espectrometria de massas em tandem (HPLC-MS/MS) / Chemical characterization of neonicotinoids in surface waters by high performance liquid chromatography with tandem mass spectrometry (HPLC MS/MS). 2017. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 126 p. Orientador: José Oscar Willian Vega Bustillos.

    Abstract: O presente estudo teve como propósito o desenvolvimento de um método para a determinação e a validação de uma metodologia para a identificação e quantificação de Neonicotinóides em águas superficiais coletadas na região de Bauru, no estado de São Paulo. As técnicas analíticas estudadas para o desenvolvimento deste método foram a cromatografia líquida de alta eficiência acoplada a espectrometria de massas em tandem (HPLC - MS/MS), a cromatografia a gás acoplada a espectrometria de massas (GC/MS) e a cromatografia a gás acoplada ao detector de captura de elétrons (GC/ECD). A classe de pesticidas Neonicotinóides foi escolhida para este trabalho por estar relacionada com um súbito desaparecimento de abelhas em colônias de todo o mundo. Este fenômeno é conhecido como colapso de desordem das colônias (Colony Collapse Disorder CCD) e o mesmo é caracterizado por uma rápida perda na população de abelhas adultas. Os Neonicotinóides utilizados neste estudo foram os compostos Clotianidina, Imidacloprido e Tiametoxam que foram proibidos na sua utilização como pesticidas na Europa pelo regulamento de execução nº 540/2011. As amostras foram concentradas utilizando as técnicas de extração em fase sólida (SPE) e extração líquido líquido (LLE) e injetadas no HPLC MS/MS, GC/MS e GC/ECD. As técnicas de GC/ECD e GC/MS não foram satisfatórias para a determinação na matriz água, pois, o limite de detecção (10 mg L-1), esta acima do valor máximo permitido na legislação da agência de proteção ambiental americana (0,6 μg L-1). A técnica de HPLC MS/MS utilizando o modo de monitoramento de reações múltiplas (MRM) provou se adequada para este estudo por obter limites de quantificação entre 5,89 a 8,06 μg L-1 e uma linearidade entre 0,9963 e 0,9993 para os três compostos.

    Palavras-Chave: insecticides; nicotine; acetylcholine; biological effects; toxicity; bees; surface waters; site characterization; chemical properties; high-performance liquid chromatography; mass spectroscopy; ion-molecule collisions; quantitative chemical analysis

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  • IPEN-DOC 23018

    SOUSA, MARIA A.S. de . Fatores associados à mortalidade na Leishmaniose visceral grave em Araguaína - TO: Caracteristicas epidemiológicas, clínicas e laboratoriais (2002 a 2015) / Factors assessed to mortality in severe visceral Leishmany in Araguaina-TO: epidemiological, clinical and laboratory characteristics (2002 to 2015). 2016. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 88 p. Orientador: Nanci do Nascimento.

    Abstract: A Leishmaniose Visceral (LV) é uma doença infecciosa de carater sistêmico. Estima-se que 350 milhões de pessoas no mundo estão expostas ao risco de infecção, com uma prevalência de 12 milhões de infectados e letalidade mundial de 59.000 casos por ano (OMS), sendo que 90%dos casos de LV ocorrem em países onde existe grande parte da população em situação de pobreza.Na América Latina a maioria dos casos ocorre no Brasil (96%) com média de 3.500 casos/ano. As áreas de maior endemia encontram-se nas regiões mais carentes do Norte e Nordeste.A donça afeta animais e o homem, podendo levar ao óbito em 100% dos casos, tendo como seu principal vetor a Lutzomyia longipalpis e como agente etiológico, a Leishmania Infantum. O Estado do Tocantins apresenta elevado número de casos autóctones, e é considerada área endêmica pelo Minisério da Saúde devido a doença estar presente na maioria dos seus municípios. A cidade de Araguaína, com 55,8% dos casos do Tocantins, é classificada pelo Ministério da Saúde como área de transmissão intensa.O objetivo geral deste trabalho foi analisar casos confirmados de Leishmaniose visceral grave CID-B55 internados no Hospital de Doenças Tropicais do Tocantins (HDT), na cidade de Araguaína - TO que evoluíram para óbito no periodo de janeiro de 2002 a dezembro de 2015. Pretendeu-se identificar e descrever dados epidemiológicos, clínicos e laboratoriais, e variáveis relacionadas ao tratamento. Foi feito um estudo epidemiológico, observacional, retrospectivo, descritivo, utilizando dados secundários de prontuários médicos de pacientes internados, no Hospital de Doenças Tropicais do Estado do Tocantins, na cidade de Araguaína - TO. Resultados: sexo masculino, 60,8 e 39,2% sexo feminino. 49,2% idade entre 0 e 10 anos; 20% maiores de 51 anos. Local de procedência em relação ao município 40,9% são de Araguaína; e ao Estado a 89% são do Tocantins. Presença de febre em 70,8%; esplenomegalia e hepatomegalia 76,7%. Hemoglobina < 7g/dl 50%, plaquetopenia 76,7%;leucopenia 50% e hipoalbuminemia 84,9%.Tempo de febre até a internação > que 30 dias 30,8%; Tempo de diagnóstico 5,1 dias; tempo de diagnóstico ao óbito 11,6 dias; RIFI 1/80 em 53,3%; Teste Rápido positivo 88,2% droga de escolha para tratmento foi Glucantime 43% seguida por anfotericina 32% e anfotericina lipossomal 25%. A principal causa do óbito na DO(Declaração de aÓbito) foi kalazar 33,3% e também Infecções respiratorias 31,7%.Conclui-se que a maior incidencia ocorre em individuo do sexo masculino menores de 10 anos, residentes no Estado do Tocantins, apresentando quadro febril prolongado, anemia severa e hipoalbuminemia grave, podendo este quadro ter influenciado na evolução ao óbito.

    Palavras-Chave: parasites; diseases; disease vectors; epidemiology; etiology; immunoassay; bioassay; inspection; feasibility studies; testing; validation; evaluated data; comparative evaluations; brazil

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  • IPEN-DOC 23017

    FERRARI, MARCELLO . Soldagem de chapas grossas em aço baixa liga temperado e revenido ASTM A514 com aço carbono ASTM A36 pelo processo arame tubular / Welding of ASTM A514 quenched and tempered low alloy steel thick plates with ASTM A36 carbon steel by FCAW process. 2016. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 128 p. Orientador: Maurício David Martins das Neves.

    Abstract: Neste trabalho foram determinadas as condições para a soldagem de chapas grossas de aço carbono ASTM A36 com aço baixo-liga temperado e revenido ASTM A514 Grau Q empregando-se o processo arame tubular. Para tanto foram soldadas diversas peças de testes com o intuito de se avaliar as condições mais adequadas de preparação e soldagem de juntas dissimilares destes materiais. A preparação foi realizada por meio de corte térmico. A temperatura de preaquecimento foi determinada através de modelos matemáticos, pelas recomendações das normas AWS D1.1 e DIN EN 1011-2 sendo posteriormente avaliada por intermédio do teste de soldabilidade tipo CTS Controlled Thermal Severity. Os parâmetros de soldagem foram determinados a partir da qualificação de um procedimento de soldagem, conforme a norma AWS D1.1. Foram avaliadas as consequências do emprego do tratamento térmico de alívio de tensões após soldagem (TTAT), pelos testes de dureza Vickers e impacto Charpy. A caracterização microestrutural foi realizada por meio de microscopia óptica e microscopia eletrônica de varredura. A caracterização das superfícies oxicortadas evidenciou os efeitos da descarbonetação e também da carbonetação. A temperatura de pré-aquecimento de 160°C determinada por meio da metodologia recomendada pelas normas AWS D1.1 e DIN EN 1011-2 mostrou-se satisfatória nos testes de soldabilidade. Foi possível a qualificação do procedimento de soldagem (EPS) com requisitos de impacto na condição "como soldado", porém na condição "após TTAT", os baixos valores de tenacidade obtidos no metal de solda, inferiores a 27J, não permitiram a qualificação de uma EPS com requisitos de impacto. Foi observada a ausência de trincas intergranulares tanto na zona afetada pelo calor quanto no metal de base ASTM A514, porém foi revelada a presença de microfases frágeis no metal de solda na condição "como soldado", especificamente na região da raiz, intensificadas pelo efeito da diluição. O aumento do teor de carbono na raiz, a presença de microfases frágeis, a grande fração de grãos colunares e de ferrita proeutetóide combinados com a baixa fração de ferrita acicular no metal de solda contribuíram para os baixos valores de tenacidade encontrados na condição "como soldado". Após o TTAT observou-se uma queda acentuada da tenacidade, inferior a 27J, do metal de solda devido à fragilização provocada pela precipitação e coalescimento de carbonetos de ferro.

    Palavras-Chave: arc welding; heat treatments; thickness; carbon steels; casting; surface properties; fracture properties; electron microscopy; optical properties; image scanners; materials testing; performance testing; standards; standardization

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  • IPEN-DOC 23164

    EVORA, MARIA C.; HIREMATH, NITILAKSHA; LU, XINYI; KANG, NAM-GOO; SILVA, LEONARDO G. de A. e ; BHAT, GAJANAN; MAYS, JIMMY. Effect of electron beam and gamma rays on carbon nanotube yarn structure. Materials Research, p. 1-7, 2017. DOI: 10.1590/1980-5373-MR-2017-0102

    Abstract: Individual carbon nanotubes (CNTs) exhibit excellent mechanical, electrical and thermal properties, leading to development of a new generation of advanced lightweight materials and spacecraft electronics substituting the electronics based on silicon. The direct assembly of CNTs into macroscopic fibers or sheets has been a way to overcome their dispersion and processing challenges. Because of a wide range of applications of this material, we investigate effectively the defects on CNT yarns structures created by electron beam and gamma sources and their impact on the morphology and mechanical properties. The irradiated samples with electron beam at doses of 400, 600 and 800 kGy had a decrease in the strength from 219.60 ± 18.90 MPa for pristine yarn to 108.86 ± 23.77, 153.15 ± 21.63, 170.50 ± 25.78 MPa, respectively. The sample irradiated with gamma in air at dose of 100 kGy had the strength increased slightly as compared with the pristine sample and an increase in the elasticity modulus from 8.79 ± 1.19 to 19.63 ± 2.02 GPa as compared to CNT pristine yarn. The quality of the CNT yarns that was gamma irradiated in air with absorbed dose of 100 kGy was not affected by the radiation process with improvement of 123% of the Young’s modulus.

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  • IPEN-DOC 23196

    SANTOS, S.C. ; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. . Bio-prototyping of europium-yttria based rods for radiation dosimetry. Materials Chemistry and Physics, v. 199, p. 557-566, 2017. DOI: 10.1016/j.matchemphys.2017.07.063

    Abstract: The application of solid state dosimeters in radiation protection has grown significantly as consequence of advances in the development of dosimetric materials using rare earths. The conception of new dosimetric materials concerns synthesis methods, which control the evolution of material structure, including further processing steps as, shaping, drying, and sintering. The present study reports a full bio-prototyping approach to produce europium doped yttria rods with potential application in radiation dosimetry. Ceramic particles synthesized by hydrothermal route were characterized by Photon Correlation Spectroscopy (PCS), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM). The effect of europium on promoting electronic defects in yttria host was evaluated by Electron Paramagnetic Resonance (EPR). Low pressure hydrothermal synthesis led to formation of rounded particles with mean diameter of 410 nm. Aqueous suspensions with 20 vol% of particles prepared at pH 10, and 0.2 wt% binder exhibited apparent viscosity of 213 mPa s, being suitable for bio-prototyping of rods. Sintering of shaped samples at 1600 degrees C for 4 h provided formation of dense ceramic rods. Europium-yttria rods containing 5 at.% Eu exhibited the most intense EPR response.

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  • IPEN-DOC 23207

    SILVA, ANGELICA M. ; ABESSA, DENIS; PAMPLIN, PAULO A.Z.; BOHRER-MOREL, MARIA B.. Ecological risk assessment of a subtropical river influenced by discharges of residues from water and sewage treatment plants. Management of Environmental Quality: An International Journal, v. 28, n. 2, p. 156-174, 2017. DOI: 10.1108/MEQ-09-2015-0169

    Abstract: Purpose – The São Lourenço River (SLR) is used to supply potable waters for the cities of São Lourenço da Serra and Juquitiba, but receives the residues from the water treatment plants (WTPs) and sewage treatment plants (STPs), respectively. The purpose of this paper is to evaluate the impacts of the discharges of Juquitiba’s WTP and STP on the quality of the SLR, by using an integrated approach based on different lines of evidence. Design/methodology/approach – Six sampling sites were established along the river and comprised areas situated upstream and downstream of the discharges. Five sampling surveys were performed between 2004 and 2006 for collecting water and sediment samples for ecotoxicological assays. In two of these campaigns, benthic community structure and geochemistry (metals, nutrients and sediment texture) were also assessed. Findings – Concentrations of P, Fe and Al in waters exceeded the national standards, but sediments were not considered to be contaminated by metals or nutrients. Water and sediments tended to exhibit marginal toxicities, excluding the sediments from JQT007 and JQT008 that were frequently toxic. Combination of geochemistry, toxicity and ecological indices indicated that some sites are not degraded, but in some stations the benthic alteration may be due to non-measured contaminants, especially in JQT007 and JQT008. Practical implications – As the use of waters from SLR for public supply has increased, these results show that action should be taken in order to reverse the environmental degradation of SRL. Originality/value – This research combined sediment and water quality assessments in order to provide a more suitable and reliable diagnostic of the environmental quality of the SLR.

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  • IPEN-DOC 23205

    SILVA, MARIA C.C. ; ANDRADE, D.A. ; QUISHIDA, ALESSANDRA. Commitment as a strategy for the adoption of an environmental management system: the case of a public research institution. Journal of US-China Public Administration, v. 14, n. 1, p. 16-25, 2017. DOI: 10.17265/1548-6591/2017.01.002

    Abstract: The objective of this paper was to examine, through a Problem Structuring Methods (PSMs) cognitive map, the possible uncertainties, complexities, and conflicts related to the commitment element, as a consequence of the environmental management adoption, through the implementation of an Environmental Management System (EMS). It was, also, proposed a measurement model of this mentioned behavior to be validated in future studies, in order to measure the commitment of all civil-service employees involved in the new management, before adopting this given system. The commitment to be analyzed through this model is divided into two components: affective and normative. The research was done with 15 managers of a Federal Public Institution, located in the state of São Paulo, Brazil, and the data that compose the cognitive map were obtained through a face-to-face interview, from May to November 2015, besides group meetings with the aforementioned managers, from December 2015 to March 2016. The results of the cognitive map analysis demonstrated the necessity to investigate the commitment factor, when there is the intention of adopting the EMS. It was, also, inferred that the suggested model, will be validated in longitudinal studies.

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  • IPEN-DOC 23016

    PORTO, LUCIANA V.F.M. . Estudo do pior caso na validação de limpeza de equipamentos de produção de radiofármacos de reagentes liofilizados. Validação de metodologia de carbono orgânico total / Worst-case study for cleaning validation of equipments in the radiopharmaceutical production of lyophilized reagents. Metodology validation of total organic carbon. 2015. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 125 p. Orientador: Margareth Mie Nakamura Matsuda.

    Abstract: Os radiofármacos são definidos como preparações farmacêuticas contendo um radionuclídeo em sua composição, são administrados intravenosamente em sua maioria, e, portanto, o cumprimento dos princípios de Boas Práticas de Fabricação (BPF) é essencial e indispensável à tais produtos. A validação de limpeza é um requisito das BPF e consiste na evidência documentada que demonstra que os procedimentos de limpeza removem os resíduos a níveis pré-determinados de aceitação, garantindo que não haja contaminação cruzada. Uma simplificação da validação dos processos de limpeza é admitida, e consiste na escolha de um produto, denominado de "pior caso" ou worst case, para representar a limpeza de todos os equipamentos da mesma linha de produção. Uma das etapas da validação de limpeza é o estabelecimento e validação do método analítico para quantificação do resíduo. O objetivo deste estudo foi estabelecer o pior caso para a validação de limpeza dos equipamentos de produção de reagentes liofilizados-RL para marcação com 99mTc, avaliar a utilização do teor de carbono orgânico total (COT) como indicador de limpeza dos equipamentos utilizados na fabricação dos RL, validar o método para determinação de CONP (carbono orgânico não purgável/volátil) e realizar testes de recuperação com o produto escolhido como pior caso. A escolha do produto pior caso baseou-se no cálculo de um índice denominado "índice para pior caso - Worst Case Index (WCI)", utilizando informações de solubilidade dos fármacos, dificuldade de limpeza dos equipamentos e taxa de ocupação dos produtos na linha de produção. O produto indicado como pior caso entre os RL foi o MIBI-TEC. Os ensaios de validação do método foram realizados utilizando-se um analisador de carbono modelo TOC-Vwp acoplado a um amostrador automático modelo ASI-V, ambos da marca Shimadzu® e controlados por software TOC Control-V Shimadzu®. Foi utilizado o método direto de quantificação do CONP. Os parâmetros avaliados na validação do método foram: conformidade do sistema, robustez, linearidade, limites de detecção (LD) e de quantificação (LQ), precisão (repetibilidade e precisão intermediária), e exatidão (recuperação) e foram definidos como: 4% acidificante, 2,5 mL de oxidante, tempo de integração da curva de 4,5 minutos, tempo de sparge de 3,0 minutos e linearidade na faixa de 40-1000 μgL-1, com coeficiente de correlação (r) e soma residual dos mínimos quadrados (r2) > 0,99 respectivamente. LD e LQ para CONP foram 14,25 ppb e 47,52 ppb, respectivamente, repetibilidade entre 0,11 4,47%; a precisão intermediária entre 0,59 a 3,80% e exatidão entre 97,05 - 102,90%. A curva analítica para Mibi mostrou-se linear na faixa de 100-800 μgL-1, com r e r2 > 0,99, apresentando parâmetros similares aos das curvas analíticas de CONP. Os resultados obtidos neste estudo demonstraram que a abordagem do pior caso para validação de limpeza é um meio simples e eficaz para diminuir a complexidade e morosidade do processo de validação, além de proporcionar uma redução nos custos envolvidos nestas atividades. Todos os resultados obtidos nos ensaios de validação de método CONP atenderam as exigências e especificações preconizadas pela norma RE 899/2003 da ANVISA para considerar a metodologia validada.

    Palavras-Chave: cleaning; equipment; radiopharmaceuticals; production; specifications; freeze protection; carbono; organic solvents; reagentes; validation; inspection; comparative evaluations

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  • IPEN-DOC 23013

    SILVA, MIRNA M.S. e . Processo oxidativo avançado com ozônio de efluentes contaminados por manganês e outros metais pesados originados na drenagem ácida em mina de urânio / Advanced oxidative process with ozone of effluents contaminated by manganese and other heavy metals originated in the acid drainage in uranium mine. 2016. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 146 p. Orientador: Humberto Gracher Riella.

    Abstract: Durante a exploração de uma mina, vários impactos são causados no meio ambiente, entre eles a geração da drenagem ácida de minas (DAM), que consiste da exposição de minerais sulfetados ao ar, água e microorganismos do tipo ferroxidantes, apresentando reações de oxidação e formação de ácido sulfúrico solubilizando metais ali presentes contaminando o solo e as águas. O objetivo deste trabalho de pesquisa foi estudar uma solução tecnológica fazendo uso da oxidação avançada com ozônio de metais pesados presentes em efluentes contaminados, em mina de urânio, com especial foco na remoção do manganês. A mina de urânio das Indústrias Nucleares do Brasil INB, em Caldas, Minas Gerais, local de aplicação deste estudo, enfrenta o problema da DAM e tem como principais contaminantes de suas águas superficiais os elementos, alumínio (Al), manganês (Mn), zinco (Zn), ferro (Fe), sulfatos (SO4+2), fluoretos (F-), metais de terras raras, alem do urânio (U) e do tório (Th). Os testes com ozônio realizados em laboratório com os efluentes da INB e in situ, mostraram uma grande eficiência para remoção do ferro, manganês e cério em até 99%. A concentração total de manganês ficou abaixo dos limites estabelecidos pela resolução 430 e 357 do CONAMA. Elementos como neodímio (Nd), lantânio (La) e zinco (Zn) pouco se oxidam com O3. O Al se mantém praticamente inalterado, enquanto que o tório e o urânio decaem, mas com o passar do tempo de ozonização voltam a se concentrar, porém com um valor inferior ao inicial. O precipitado obtido após a ozonização consiste de até 85% de oxido de manganês. A fim de descartar, após a ozonização, o efluente líquido para o ambiente é necessário uma correção do pH, de modo a atender os parâmetros da legislação CONAMA, sendo utilizado 50 a 86% menos reagente (CaOH2), do que as quantidades utilizadas no processo adotado pela INB.

    Palavras-Chave: ozone; atmospheric explosions; sulfuric acid; heavy metals; rare earths; oxidation; radioactive effluents; liquid wastes; uranium mines; drainage; manganese; ground water; waste processing; waste treatment; nuclear industry; environmental protection; safety standards

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  • IPEN-DOC 23212

    TANAKA, MAGALI N.; SANTOS, SOLANGE T.S.; GOUVEIA, MARIZE; SANTOS FILHO, MERY dos; COSENTINO, IVANA C. ; BARBOSA NETO, JAIR B.; TUFIK, SERGIO; MATOS, JIVALDO do R.; MERCURI, LUCILDES P.. Encapsulation study of citalopram and risperidone into nanostructured silica SBA-15 for in vitro release evaluation. Journal of Thermal Analysis and Calorimetry, v. 127, n. 2, p. 1725-1732, 2017. DOI: 10.1007/s10973-016-5995-4

    Abstract: Ordered mesoporous silica, SBA-15, presents non-toxic nature; high pore volume and high surface area; thermal, hydrothermal and mechanical stabilities. These features may enable its use as a carrier for commonly prescribed drugs in psychiatric practice: citalopram (CIT) and risperidone (RIS). Thermogravimetry/derivative thermogravimetry (TG/DTG) and ultraviolet and visible absorption spectrophotometry (UV-Vis) were used to determine drug quantity into/onto ECIT (CIT encapsulated into SBA-15), ERIS (RIS encapsulated into SBA-15), MCIT (mixture of CIT with SBA-15) and MRIS (mixture of RIS with SBA-15). All materials were characterized through: TG/DTG, differential scanning calorimetry, elemental analysis, Fourier transform infrared absorption spectrophotometry and nitrogen adsorption-desorption. A general solvent-based method for loading these psychoactive drugs into non-functionalized SBA-15 showed to retard their liberation in simulated gastric and intestinal media when compared to physical mixtures performance. It is expected that the functionalization of this nanostructured silica may increasingly extend the dissolution of CIT and RIS after encapsulation process, leading to application in controlled release systems.

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  • IPEN-DOC 23011

    SEO, DANIELE . Desenvolvimento de biomarcador específico de células beta pancreáticas (incretina radiomarcada) para imagem da massa beta funcional em diabéticos e obesos: estudo em modelo animal / Development of biomarker specific of pancreatic beta cells (incretin radiolabelled) for image of beta functional mass in diabetic and obese: study in animal model. 2017. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 127 p. Orientador: Bluma Linkowski Faintuch.

    Abstract: O aumento nos casos de obesidade em todo o mundo tem gerado grande preocupação e estimulado pesquisas na prevenção e tratamento dessa condição patológica. A combinação de diabetes tipo 2 ou resistência insulínica com obesidade agrava o potencial evolutivo da enfermidade. Mesmo pacientes submetidos com sucesso à cirurgia bariátrica ou metabólica, podem não se curar do diabetes, pois a melhora das taxas circulantes de glicose e insulina nem sempre corresponde à recuperação da massa beta pancreática. Até o momento, não há consenso sobre como medir a massa de células beta in vivo. As ferramentas disponíveis padecem de baixa sensibilidade e especificidade, muitas vezes revelando-se também complexas e dispendiosas. Incretinas radiomarcadas ,como os análogos do peptídeo glucagon-like-peptide-1 / GLP-1, têm-se revelado promissoras para avaliação de células beta pancreáticas, em diabetes e insulinoma. O objetivo do presente trabalho foi o desenvolvimento de dois conjugados de análogo de incretina GLP-1, marcados com tecnécio-99m, a fim de propor um método não invasivo de imagem, para monitoração da massa de células beta pancreáticas, em organismos afetados por obesidade. O estudo foi conduzido em diferentes modelos animais, incluindo obesidade induzida por dieta hiperlipídica, estado pós-obesidade em que o distúrbio inicialmente gerado foi parcialmente corrigido, e como controle, diabetes induzido com aloxana. Nos resultados, os radiotraçadores alcançaram um rendimento radioquímico superior a 97%. O melhor radiomarcador, dentre os dois análogos ensaiados, foi o 99mTc-HYNIC-βAla-Exendin-4. Animais com obesidade induzida por dieta revelaram captação reduzida nas células beta pancreáticas. A restrição dietética (estado pós-obesidade) não se seguiu de recuperação completa, embora notável melhora de glicemia haja sido observada. Estudos futuros são indicados em modelos de obesidade, diabetes tipo 2 e tratamento dietético, incluindo cirurgia bariátrica e metabólica.

    Palavras-Chave: biological models; bioassay; biological markers; labelled compounds; endocrine diseases; metabolic diseases; insulin; diabetes mellitus; quantitative chemical analysis; animal cells; in vivo; radioimmunoscintigraphy; technetium 99; image processing

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  • IPEN-DOC 23190

    QUINTO JUNIOR, JOSE; AMARAL, MARCELLO M.; FRANCCI, CARLOS E.; ANA, PATRICIA A.; MORITZ, ANDREAS; ZEZELL, DENISE M. . Evaluation of intra root canal Er,Cr:YSGG laser irradiation on prosthetic post adherence. Journal of Prosthodontics: Implant Esthetic and Reconstructive Dentistry, p. 1-5, 2017. DOI: 10.1111/jopr.12609

    Abstract: Purpose In clinical prosthetics procedures, including endodontics and post fixation, the presence of a smear layer can reduce the post bond strength. An Er,Cr:YSGG laser, which emits at 2780 nm, can promote a smear-layer-free surface due to the ablation process. Considering these aspects, the purpose of this work was to evaluate the influence of Er,Cr:YSGG laser irradiation using either a radial or an axial fiber tip on the bond strength of three resin cements to the fiber-reinforced composite posts. Materials and Methods Ninety recently extracted single rooted human teeth had their root canal instrumented and were randomly distributed into nine experimental groups, in which three resin cements (total-etching Variolink II, self-etching Panavia F, and self-adhesive RelyX Unicem Aplicap) and three root canal treatments (no treatment, laser irradiation using the radial fiber tip, laser irradiation using the axial fiber tip) were used. Specimens were then sectioned into three sections (cervical, middle, and apical thirds) with two slices on each section. A push-out test was performed on each slice, and the values were recorded as MPa. The push-out data were analyzed by a Ryan-Joiner normality test followed by a two-way ANOVA test and Tukey pairwise comparison. The statistical analysis was performed on each third section separately, with a 5% significance level. Results Laser irradiation with axial fiber tip significantly increased the post bond strength of RelyX Unicem Aplicap on middle third of specimens (p < 0.001) when compared to other root canal treatments (unlased or irradiated with radial tip). Considering the Panavia resin cement, laser irradiation with either axial or radial tips promoted a significant increase on the post bond strength of middle third when compared to unlased specimens (p < 0.001); however, laser irradiation did not influence the post bond strength of Variolink resin cement. Conclusions The use of the Er,Cr:YSGG laser for clinical prosthetics procedures enhances the post bond strength of Panavia and RelyX Unicem Aplicap resin cements, mainly at middle third of roots, and does not interfere with the bond strength of Variolink resin cement. For the RelyX Unicem Aplicap system, the use of axial tip is most advantageous and can be recommended for future clinical application.

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  • IPEN-DOC 23217

    ZAHARESCU, TRAIAN; SCAGLIUSI, SANDRA R. ; LUCHIAN, ANA M.; LUGAO, ADEMAR B. . Degradability characterization of EPDM/IIR blends by γ-irradiation. Journal of Polymers and the Environment, v. 64, 2017. DOI: 10.1007/s10924-017-0966-9

    Abstract: In this paper the modifications induced in butyl rubbers (pristine, chlorinated and brominated sorts) by γ-irradiation are investigated by swelling, chemiluminescence and FT-IR. The susceptibility of butyl rubbers for the generation of radicals orders their stabilities in the following sequence: IIR > IIR—Cl > IIR—Br. The incorporation of butyl rubbers into ethylene-propylene terpolymer matrix brings about increased densities of radicals initiating modifications in the oxidation state in respect with recombination, which are intensified as the processing dose increases. Based on the variation of carbonyl and hydroxyl indices the favorable route for the recycling EPDM based formulations would be suggested in this study. The chemiluminescence spectra proving the formation of peroxyl radicals at about 100 °C prove their availability as reclaiming solutions. IIR—Br is the recommendable butyl rubber for the recovery procedure by association with EPDM. The suitability of IIRs for recycling purposes is analyzed by the variation in their crosslink densities, free volumes and swelling degrees. The crosslinking behavior of stabilized EPDM/IIR blends that runs to the improvement of durability is depicted by Charlesby–Pinner representation, which involves the different simultaneous contribution of scission and crosslinking processes.

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  • IPEN-DOC 23189

    PRADO, ANDRESSA R.; YOKAICHYIA, FABIANO; FRANCO, MARGARETH K.K.D. ; SILVA, CAMILA M.G. da; OLIVEIRA-NASCIMENTO, LAURA; FRANZ-MONTAN, MICHELLE; VOLPATO, MARIA C.; CABECA, LUIS F.; PAULA, ENEIDA de. Complexation of oxethazaine with 2-hydroxypropyl-bcyclodextrin: increased drug solubility, decreased cytotoxicity and analgesia at inflamed tissues. Journal of Pharmacy and Pharmacology, v. 69, n. 6, p. 652-662, 2017. DOI: 10.1111/jphp.12703

    Abstract: ObjectivesOxethazaine (OXZ) is one of the few local anaesthetics that provides analgesia at low pH, but presents poor solubility, cytotoxicity and no parenteral formulations. To address these issues, we aimed to prepare OXZ host-guest inclusion complex with hydroxypropyl-beta-cyclodextrin (HP--CD). MethodsThe inclusion complex was formed by co-solubilization, followed by a job plot analysis to determine stoichiometry of complexation and dialysis equilibrium analysis (based on UV/VIS absorption and fluorescence profiles of OXZ). Complex formation was confirmed by phase-solubility data, X-ray, Scanning Electron Microscopy and DOSY-H-1-NMR experiments. In vitro cytotoxicity was analysed by MTT test in 3T3 fibroblasts. In vivo analgesia was tested by Von Frey test (inflammatory wounds - rats). Key findingsOxethazaine complexed (1 : 1 molar ratio) with HP--CD, as indicated by loss of OZX crystalline structure (X-ray) and strong host: guest interaction (NMR, K = 198/M), besides increased solubility. In vitro cell survival improved with the complex (IC50 OXZ = 28.9 m, OXZ : HP--CD = 57.8 m). In addition, the complex (0.1% OXZ) promoted in vivo analgesia for the same time that 2% lidocaine/epinephrine did. Conclusion Our results show that complexation improved physicochemical and biological properties of OXZ, allowing its application to inflamed tissues by parenteral routes.

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  • IPEN-DOC 23129

    BLAY, ALBERTO ; BLAY, CLAUDIA C. ; TUNCHEL, SAMY; GEHRKE, SERGIO A.; SHIBLI, JAMIL A.; GROTH, EDUARDO B.; ZEZELL, DENISE M. . Effects of a low-intensity laser on dental implant osseointegration: removal torque and resonance frequency analysis in rabbits. Journal of Oral Implantology, v. 42, n. 4, p. 316-320, 2016. DOI: 10.1563/aaid-joi-D-15-00064

    Abstract: The objective of this study was to investigate how a low-intensity laser affects the stability and reverse torque resistance of dental implants installed in the tibia of rabbits. Thirty rabbits received 60 dental implants with the same design and surface treatment, one in each proximal metaphysis of the tibia. Three groups were prepared (n = 10 animals each): conventional osseointegration without treatment (control group), surgical sites irradiated with a laser beam emitted in the visible range of 680 nm (Lg1 group), surgical sites irradiated with a laser beam with a wavelength in the infrared range of 830 nm (Lg2 group). Ten irradiation sessions were performed 48 hours apart; the first session was during the immediate postoperative period. Irradiation energy density was 4 J/cm(2) per point in 2 points on each side of the tibias. The resonance frequency and removal torque values were measured at 2 time points after the implantations (3 and 6 weeks). Both laser groups (Lg1 and Lg2) presented a significant difference between resonance frequency analysis values at the baseline and the values obtained after 3 and 6 weeks (P > .05). Although the removal torque values of all groups increased after 6 weeks (P < .05), both laser groups presented greater mean values than those of the control group (P < .01). Photobiomodulation using laser irradiation with wavelengths of 680 and 830 nm had a better degree of bone integration than the control group after 6 weeks of observation time.

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  • IPEN-DOC 23163

    DURAZZO, M. ; VIEIRA, E. ; CARVALHO, E.F.U. de ; RIELLA, H.G. . Evolution of fuel plate parameters during deformation in rolling. Journal of Nuclear Materials, v. 490, p. 197-210, 2017. DOI: 10.1016/j.jnucmat.2017.04.018

    Abstract: The Nuclear and Energy Research Institute IPEN/CNEN-SP routinely produces the nuclear fuel necessary for operating its research reactor, lEA-R1. This fuel consists of fuel plates containing U3Si2-Al composites as the meat, which are fabricated by rolling. The rolling process currently deployed was developed based on information obtained from literature, which was used as a premise for defining the current manufacturing procedures, according to a methodology with an essentially empirical character. Despite the current rolling process being perfectly stable and highly reproducible, it is not well characterized and is therefore not fully known. The objective of this work is to characterize the rolling process for producing dispersion fuel plates. Results regarding the evolution of the main parameters of technological interest, after each rolling pass, are presented. Some defects that originated along the fuel plate deformation during the rolling process were characterized and discussed. The fabrication procedures for manufacturing the fuel plates are also presented. (C) 2017 Elsevier B.V. All rights reserved.

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  • IPEN-DOC 23197

    SANTOS, LAURO R. dos ; DURAZZO, MICHELANGELO ; CARVALHO, ELITA F.U. de ; RIELLA, HUMBERTO G. . Effect of Al(OH)3 on the sintering of UO2–Gd2O3 fuel pellets with addition of U3O8 from recycle. Journal of Nuclear Materials, v. 493, p. 30-39, 2017. DOI: 10.1016/j.jnucmat.2017.05.050

    Abstract: The incorporation of gadolinium as burnable poison directly into nuclear fuel is important for reactivity compensation, which enables longer fuel cycles. The function of the burnable poison fuel is to control the neutron population in the reactor core during its startup and the beginning of the fuel burning cycle to extend the use of the fuel. The implementation of UO2-Gd2O3 poisoned fuel in Brazil has been proposed according to the future requirements established for the Angra-2 nuclear power plant. The UO2 powder used is produced from the Ammonium Uranyl Carbonate (AUC). The incorporation of Gd2O3 powder directly into the AUC-derived UO2 powder by dry mechanical blending is the most attractive process, because of its simplicity. Nevertheless, processing by this method leads to difficulties while obtaining sintered pellets with the minimum required density. The cause of the low densities is the bad sintering behavior of the UO2-Gd2O3 mixed fuel, which shows a blockage in the sintering process that hinders the densification. This effect has been overcome by microdoping of the fuel with small quantities of aluminum. The process for manufacturing the fuel inevitably generates uranium-rich scraps from various sources. This residue is reincorporated into the production process in the form of U3O8 powder additions. The addition of U3O8 also hinders densification in sintering. This study was carried out to investigate the influence of both aluminum and U3O8 additives on the density of fuel pellets after sintering. As the effects of these additives are counterposed, this work studied the combined effect thereof, seeking to find an applicable composition for the production process. The experimental results demonstrated the effectiveness of aluminum, in the form of Al(OH)3, as an additive to promote increase in the densification of the (U,Gd)O2 pellets during sintering, even with high additions of U3O8 recycled from the manufacturing process.

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  • IPEN-DOC 23181

    MONTEIRO, WALDEMAR A. ; SILVA, SILVIO L.V. da ; SILVA, LUCIANA V. da ; ANDRADE, ARNALDO H.P. de; SILVA, LUIS C.E. da . Characterization of nickel alloy 600 with ultra-fine structure processed by Severe Plastic Deformation technique (SPD). Journal of Materials Science and Chemical Engineering, v. 5, n. 4, p. 33-44, 2017. DOI: 10.4236/msce.2017.54004

    Abstract: High strength nickel based alloys are used in a multitude of advanced systems where lightweight, high power density mechanical power transmission systems are required. Components such as gears, bearings and shafts could be made significantly smaller and more durable if a major improvement in nickel based alloy mechanical properties could be achieved. An important refinement in grain size (includes nanometric level) is thought to be a promising method for achieving fundamental improvements in mechanical properties. Grain size is known to have a significant effect on the mechanical behavior of materials. One of the most favorable methods of achieving extreme grain refinement is by subjecting the materials to severe plastic deformation (SPD). The principal microstructural variations in superalloys are the precipitation amount and morphology, grain size and the distribution of carbide precipitation that could reduce the mechanical properties of the alloys. This work shows optical and transmission electron microscopy analysis and also hardness data after severe plastic deformation (pure shear stress).

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  • IPEN-DOC 23203

    SHRIVASTAVA, NAVADEEP; KHAN, L.U.; KHAN, Z.U.; VARGAS, J.M.; MOSCOSO-LONDONO, O.; OSPINA, CARLOS; BRITO, H.F.; JAVED, YASIR; FELINTO, M.C.F.C. ; MENEZES, A.S.; KNOBEL, MARCELO; SHARMA, S.K.. Building block magneto-luminescent nanomaterials of iron-oxide/ZnS@LaF3:Ce3+,Gd3+,Tb3+ with green emission. Journal of Materials Chemistry C, v. 5, n. 9, p. 2282-2290, 2017. DOI: 10.1039/c6tc05053k

    Abstract: The preparation of novel triply-doped bifunctional Fe3O4/ZnS@LaF3:xCe3+,xGd3+,yTb3+ (x = 5; y = 5, 10 and 15 mol%) nanocomposites with efficient optical and magnetic features has been reported. The ZnS semiconductor functionalized Fe3O4 particles were coated with LaF3:RE3+ materials via a chitosanassisted co-precipitation method. The size of iron oxide B7.2 nm and trigonal structures of bifunctional nanostructures were confirmed through X-ray diffraction and high-resolution transmission electron microscopy. The static magnetic measurements supported and manifested the superparamagnetic behavior of the materials at 300 K. A broad emission band was observed in the blue region (400–550 nm) due to the sulphur vacancy on the surface of the Fe3O4/ZnS nanocomposite. For a triply doped bifunctional nanostructure, the excitation spectra revealed broad absorption bands centered at around 270 nm, which were attributed to the 4f(7F7/2) - 5d interconfigurational transition of the Ce3+ ion accompanied by narrow absorption lines arising from the 4f–4f intraconfigurational transitions of the Tb3+ ion. The emission spectra of the nanocomposites showed characteristic narrow emission lines assigned to the 5D4 - 7FJ transitions (J = 6–0) of the Tb3+ ion. The energy transfer process from the Ce3+ - Gd3+ - Tb3+ ions has also been presented and discussed. Furthermore, the structural, photoluminescence and magnetic properties of Fe3O4/ZnS@LaF3:RE3+ suggested that it may be an efficient candidate for magnetic light-converting molecular devices (MLMCDs) and high energy radiation detection.

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  • IPEN-DOC 23206

    SILVA, FLAVIA R.O. ; LIMA, NELSON B. ; YOSHITO, WALTER K. ; BRESSIANI, ANA H.A. ; GOMES, LAERCIO . Development of novel upconversion luminescent nanoparticle of Ytterbium/Thulium–doped beta tricalcium phosphate. Journal of Luminescence, v. 187, p. 240-246, 2017. DOI: 10.1016/j.jlumin.2017.03.029

    Abstract: A novel class of upconversion luminescent nanocrystals of Yb/Tm:calcium deficient hydroxyapatite were synthesized by co-precipitation method in aqueous solution (pH adjusted to 6) and specially heat-treated with microwave radiation at different temperatures (from 900 °C to 1000 °C) and times (2–10 min) to produce small nanocrystals of Yb/Tm:β-tricalcium phosphate (β-TCP). As a result, we report for the first time, a single-phase Yb/Tm-doped β-TCP nanocrystals with a mean crystallite size of 55.3 nm. This material has an efficient visible luminescence from the 1G4 (blue emission) and 3F2 (red emission) and near infrared emission from the 3H4 excited states of Tm3+ induced by the Yb3+→Tm3+ energy transfer under laser excitation (Yb3+) at 972 nm. This β-TCP activated by Yb3+ and Tm3+ ions constitutes a new nano-fluoroprobe that can be used as optical contrast agents, affording high resolution and sensitivity for visible-near infrared applications.

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  • IPEN-DOC 23177

    LIMA, VERA M.F. de ; HANKE, WOLFGANG. Extracellular matrix and its role in conveying glial/neural interactions in health and disease. Journal of Integrative Neuroscience, v. 16, n. 1, p. 93-106, 2017. DOI: 10.3233/JIN-170012

    Abstract: We review the concepts and findings that may be related to the occurrence of non-linear glial/neural dynamics involving interactions between polyelectrolytes of the extracellular matrix and the basement membranes that cover the endfeet of glia at CNS interfaces. Distortions of perception and blocking of learning expressed in functional syndromes are interpreted as macroscopic electrochemical patterns that emerge in grey matter through glial/neural interactions.

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  • IPEN-DOC 23192

    RODRIGUES, PATRICIA S. de M.; BERTOLIN, APARECIDO O.; FUCASE, TAMARA M. ; GALLUZZI, FERNANDA M.; SILVA, EVELLIN C.; MARUMO, MARIA H.B. . Avaliação da atividade citotóxica dos extratos etanólicos da casca e das folhas da Terminalia fagifolia Mart. sobre células normais e tumorais / Assessment of the cytotoxic activity of ethanol extracts from the bark and leaves of terminalia fagifolia mart. on normal and tumor cells. Journal of Health and Biological Sciences, v. 5, n. 1, p. 16-23, 2017. DOI: 10.12662/2317-3076jhbs.v5i1.1068.p16-23.2017

    Abstract: Introdução: A procura por novas alternativas terapêuticas, como as que utilizam as plantas medicinais, tem despertado grande interesse da comunidade científica na busca por tratamentos mais eficientes para as doenças, incluindo o câncer. Terminalia fagifolia Mart. é uma planta medicinal encontrada no Cerrado brasileiro, usada popularmente no tratamento de aftas e tumores. Objetivos: Avaliar a atividade citotóxica dos extratos etanólicos da casca e das folhas da Terminalia fagifolia em linhagens celulares NIH 3T3 e L929 e tumorais PC3 e B16F10. Métodos: Foi realizada a metodologia de determinação da viabilidade celular em ensaio com monocamada de células utilizando o ensaio MTS. As linhagens NIH 3T3, L929, PC3 e B16F10 foram expostas por 24 horas a diferentes concentrações dos extratos etanólicos da casca e folhas da Terminalia fagifolia. Resultados: Os resultados adquiridos mostraram que os extratos apresentaram viabilidade celular, sendo considerada de moderada a alta, para as células normais NIH 3T3 e L929 e citotoxicidade severa para as células tumorais PC3 e B16F10. Dessa forma, torna-se necessária a continuidade dos estudos com essa planta, pois os extratos da casca e das folhas apresentaram atividades antitumorais muito promissoras. Conclusões: Os extratos da casca e das folhas demonstraram viabilidade celular ≥ 50% nas linhagens celulares normais NIH 3T3 e L929 e demonstraram atividade citotóxica para as linhagens tumorais PC3 e B16F10, apresentando redução da viabilidade celular em torno de 60% e 70%, respectivamente.

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  • IPEN-DOC 23172

    HATJE, VANESSA; ATTISANO, KARINA K.; SOUZA, MARCELO F.L. de; MAZZILLI, BARBARA ; OLIVEIRA, JOSELENE de ; MORA, TAMIRES de A. ; BURNETT, WILLIAM C.. Applications of radon and radium isotopes to determine submarine groundwater discharge and flushing times in Todos os Santos Bay, Brazil. Journal of Environmental Radioactivity, v. 178-179, p. 136-146, 2017. DOI: 10.1016/j.jenvrad.2017.08.004

    Abstract: Todos os Santos Bay (BTS) is the 2nd largest bay in Brazil and an important resource for the people of the State of Bahia. We made measurements of radon and radium in selected areas of the bay to evaluate if these tracers could provide estimates of submarine groundwater discharge (SGD) and flushing times of the Paraguaçu Estuary and BTS.We found that there were a few areas along the eastern and northeastern shorelines that displayed relatively high radon and low salinities, indicating possible sites of enhanced SGD. A time-series mooring over a tidal cycle at Marina do Bonfim showed a systematic enrichment of the short-lived radium isotopes 223Ra and 224Ra during the falling tide. Assuming that the elevated radium isotopes were related to SGD and using measured radium activities from a shallow well at the site, we estimated groundwater seepage at about 70 m3/day per unit width of shoreline. Extrapolating to an estimated total shoreline length provided a first approximation of total (fresh þ saline) SGD into BTS of 300 m3/s, about 3 times the average river discharge into the bay. Just applying the shoreline lengths from areas identified with high radon and reduced salinity results in a lower SGD estimate of 20 m3/s. Flushing times of the Paraguaçu Estuary were estimated at about 3e4 days based on changing radium isotope ratios from low to high salinities. The flushing time for the entire BTS was also attempted using the same approach and resulted in a surprisingly low value of only 6e8 days. Although physical oceanographic models have proposed flushing times on the order of months, a simple tidal prism calculation provided results in the range of 4e7 days, consistent with the radium approach. Based on these initial results, we recommend a strategy for refining both SGD and flushing time estimates.

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  • IPEN-DOC 23145

    TESAN, FIORELLA; CERQUEIRA-COUTINHO, CRISTAL; SALGUEIRO, JIMENA; ALBERNAZ, MARTA de S.; PINTO, SUYENNE R.; REIS, SARA R.R. dos; BERNARDES, EMERSON S. ; CHIAPETTA, DIEGO; ZUBILLAGA, MARCELA; SANTOS-OLIVEIRA, RALPH. Characterization and biodistribution of bevacizumab TPGS-based nanomicelles: Preliminary studies. Journal of Drug Delivery Science and Technology, v. 36, p. 95-98, 2016. DOI: 10.1016/j.jddst.2016.09.011

    Abstract: Bevacizumab is an FDA approved monoclonal antibody (anti VEGF) indicated in many cancers, mostly metastatic ones. D-alpha-tocopheryl polyethylene glycol succinate (TPGS) is the water-soluble form of vitamin E which usually forms micelles. This work aims to report preliminary results of the biodistribution of a TPGS based nano-micelle delivery system for bevacizumab in a gastric cancer xenograft model. Evaluation of the biodistribution of micelles/bevacizumab-99mTc was performed in Balb/c nude mice carrying MKN45 cell line xenograft. The nano-radiopharmaceutical (3.7 MBq/0.2 mL) was administered intraocularly and biodistribution was assesed 1 h post administration. The activity in each organ and blood was determined by a gamma counter. Mean size was 10 +/- 1 nm for pure TPGS and 11 +/- 1 nm for bevacizumab-TPGS respectively. Biodistribution showed that the highest uptake was found in both lungs and liver. Kidneys had also an important uptake. The tumor accumulated moderate to low radiolabeled nanomicelles, nevertheless tumor/blood ratio was very high. These preliminary results may help as a start point to continue evaluating the potential of radiolabeled bevacizumab-TPGS based nanomicelles to be used as a theranostic agent.

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  • IPEN-DOC 23173

    JOAO-SOUZA, SAMIRA H.; BEZERRA, SAVIO J.C.; FREITAS, PATRICIA M. de; LIMA, NELSON B. de ; ARANHA, ANA C.C.; HARA, ANDERSON T.; SCARAMUCCI, TAIS. In situ evaluation of fluoride-, stannous- and polyphosphate-containing solutions against enamel erosion. Journal of Dentistry, v. 63, p. 30-35, 2017. DOI: 10.1016/j.jdent.2017.05.014

    Abstract: Objective: To evaluate the anti-erosive effect of solutions containing sodium fluoride (F: 225 ppm of fluoride), sodium fluoride + stannous chloride (F + Sn: 225 ppm of fluoride + 800 ppm of stannous), sodium fluoride + stannous chloride + sodium linear polyphosphate (F + Sn + LPP: 225 ppm of fluoride + 800 ppm of stannous + 2% of sodium linear polyphosphate), and deionized water (C: control), using a four-phase, single-blind, crossover in situ clinical trial. Methods: In each phase, 12 volunteers wore appliances containing 4 enamel specimens, which were submitted to a 5-day erosion-remineralization phase that consisted of 2 h of salivary pellicle formation with the appliance in situ, followed by 2 min extra-oral immersion in 1% citric acid (pH 2.4), 6x/day, with 90 min of exposure to saliva in situ between the challenges. Treatment with the test solutions was performed extra-orally for 2 min, 2x/day. At the end of the experiment, surface loss (SL, in mu m) was evaluated by optical profilometry. Data were analyzed using ANOVA and Tukey tests (alpha = 0.05). The surface of additional specimens was evaluated by x-ray diffraction after treatments (n = 3). Results: C (mean SL +/- standard-deviation: 5.97 +/- 1.70) and F (5.36 +/- 1.59) showed the highest SL, with no significant difference between them (p > 0.05). F + Sn (2.68 +/- 1.62) and F + Sn + LPP (2.10 +/- 0.95) did not differ from each other (p > 0.05), but presented lower SL than the other groups (P < 0.05). Apatite and stannous deposits on specimen surfaces were identified in the x-ray analysis for F+ Sn and F + Sn + LPP. Conclusions: Sodium fluoride solution exhibited no significant anti-erosive effect. The combination between sodium fluoride and stannous chloride reduced enamel erosion, irrespective of the presence of linear sodium polyphosphate. Clinical significance: Under highly erosive conditions, sodium fluoride rinse may not be a suitable alternative to prevent enamel erosion. A rinse containing sodium fluoride and stannous chloride was shown to be a better treatment option, which was not further improved by addition of the sodium linear polyphosphate.

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  • IPEN-DOC 23147

    ALVES, RODRIGO H.; REIS, THAIS V. da S. ; ROVANI, SUZIMARA ; FUNGARO, DENISE A. . Green synthesis and characterization of biosilica produced from sugarcane waste ash. Journal of Chemistry, n. 6129035, 2017. DOI: 10.1155/2017/6129035

    Abstract: In this study, ash fromsugarcane waste was used in the synthesis of biosilica using alkaline extraction followed by acid precipitation. Different parameters that could influence the silica particle synthesis were evaluated. The ash and synthesized biosilica were characterized by a combination of spectroscopic and chemical techniques such as XRD, XRF, SEM, particle size analyser, N2 adsorption analysis, TGA, and FTIR. The best condition for biosilica production was achieved with fusion method and aging temperature of 80∘C for 1 h during gel formation. X-ray powder diffraction pattern confirms the amorphous nature of synthesized silica.The purity of the prepared silica was 99% silica which was confirmed bymeans of XRF.Theexperimental data suggest that the sugarcane waste ash could be converted into a value-added product, minimizing the environmental impact of disposal problems.

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  • IPEN-DOC 23186

    PAREDES, WILBER E.B. ; ANDRADE, DELVONEI A. de . ATR-FTIR assessment of the biochemical composition and micro hardness of the hard tissues of oral cavity submitted to gamma irradiation. Journal of Cancer Science & Therapy, v. 9, n. 4, p. 379-388, 2017. DOI: 10.4172/1948-5956.1000446

    Abstract: Back ground: Clinical radiotherapy is one of the most important techniques for the treatment of malignant lesions in head and neck; however, exposure to ionizing radiation may lead to both systemic and local complications, immediately and after this treatment, where the main issue is the xerostomia and its consequent oral mucositis. Regarding late complications produced by radiation, decay of radiation and osteoradionecrosis, both dosedependent lesions, showed a high level of incidence in recent decades and it would be difficult to manage, although patients referred after treatment’s completion and under the influence of local factors. Methodology: Then, this study evaluated the effect of ionizing radiation from gamma source onto samples of enamel, root dentin and jawbone samples undergone to the same absorbed dose/dose rate that those in patients with head and neck cancer. The non-irradiated and irradiated samples were analyzed by microhardness surface analysis; scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (ATR-FTIR). Results and Discussion: Microhardness data were analyzed statistically with a confidence level of 95% (p value <0.05%), using parametric Student’s t-test for related averages and ANOVA statistical test, finding a statistically significant result (p=0.00) to all four groups samples. Conclusion: It was observed a high deleterious and statistical significant effect of gamma radiation on hard tissues from oral cavity, regarding to physical, compositional and morphological properties.

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  • IPEN-DOC 23200

    SCHELL, JULIANA; LUPASCU, DORU C.; CARBONARI, ARTUR W. ; MANSANO, RONALDO D.; FREITAS, RAFAEL S.; GONCALVES, JOAO N.; DANG, THIEN T.; ISOLDE COLLABORATION; VIANDEN, REINER. Cd and In-doping in thin film SnO2. Journal of Applied Physics, v. 121, n. 19, p. 195303-1 - 195303-5, 2017. DOI: 10.1063/1.4983669

    Abstract: In this paper, we investigate the effects of doping in the local structure of SnO2 by measuring the hyperfine interactions at impurity nuclei using the Time Differential Perturbed Gamma-Gamma Angular Correlation (TDPAC) method in addition to density functional theory simulations. The hyperfine field parameters have been probed as a function of the temperature in thin film samples. The experimental results reveal that Cd-117/In and In-111/Cd are incorporated and stabilized in the SnO2 lattice replacing the cationic site. Significant differences in the electric field gradient were observed from TDPAC measurements with both the probe nuclei. Furthermore, the absence of strongly damped spectra further indicates that implanted Cd atoms (for Cd-117/In probe nuclei measurements) easily occupy regular substitutional Sn sites with good stability. The simulated value for the electric field gradient obtained with the first oxygen neighbor removed is closer to the experimental value observed for Cd-117, which also indicates this configuration as stable and present in the sample.

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  • IPEN-DOC 23150

    BARDELLA, FERNANDO ; RODRIGUES, ANDRE M. ; LEAL NETO, RICARDO M. . CrystalWalk: crystal structures, step by step. Journal of Applied Crystallography, v. 50, p. 949-950, 2017. DOI: 10.1107/S160057671700560X

    Abstract: CrystalWalk is a crystal editor and visualization software designed for teaching materials science and engineering. Based on WebGL/HTML5, it provides an accessible and interactive platform to students and teachers by introducing a simplified crystallographic approach that creates crystal structures by combining a lattice with a motif without the use of its internal symmetry. CrystalWalk is the first software to use solely translational symmetry, aiming to introduce engineering students to the basic concepts of lattice and motif. Although very restrictive from the crystallographic point of view, CrystalWalk makes it simple for students to experiment, reproduce and visualize, in an interactive manner, most of the crystal structures that are commonly introduced in materials science and engineering curricula.

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  • IPEN-DOC 23146

    ALVAREZ, RAFAEL H.; NATAL, FABIO L.N.; ALMEIDA, BEATRIZ E. ; OLIVEIRA, JOAO E. ; MELO, ALFREDO J.F.; RIBELA, MARIA T.C. ; BARTOLINI, PAOLO . Biological activity of different batches of equine chorionic gonadotropin as determined by reversed-phase high-performance liquid chromatography and in vivo assay. Journal of Advances in Medical and Pharmaceutical Sciences, v. 12, n. 2, p. 1-9, 2017. DOI: 10.9734/JAMPS/2017/31956

    Abstract: Aims: To evaluate the physicochemical profile of commercial batches of eCG, in order to find if differences can be related to their biological activity. Study Design: Commercial eCG was analyzed by reversed-phase high-performance liquid chromatography (RP-HPLC) and in vivo bioassay. Place and Duration of Study: Department of Biotechnology (IPEN-CNEN) and Animal antibody production Laboratory (Animal Science Institute), between June 2013 and April 2014. Methodology: Two commercial eCG batches for veterinary use (I and II) and an eCG official International Standard from the World Health Organization (WHO) were analyzed by RP-HPLC. Additionally, two experiments were designed to validate the biological activity. In experiment 1, groups of prepubertal 21–25 day old Wistar female rats (n = 6/group) received the equivalent to 0 UI (saline) and 10 IU of eCG of each one of these preparations. Autopsy was performed 48 h later and ovaries were removed and weighed. The experiment 2 was designed to determine whether increasing the dose of less active eCG batches could increase the ovarian response. Therefore, groups of prepubertal rats (n = 6/group) were treated with 10 and 30 IU eCG from batch II, while eCG from WHO (10 IU) and saline were control. The evaluation of ovarian response was done similar to Experiment 1. Differences among treatments were analyzed by one-way ANOVA. Results: Results of RP-HPLC showed differences in the main tR peak profile (tR 26.7) of the standard WHO compared with eCG batches I and II. In experiment 1, the average ovarian weight of rats treated with eCG from WHO (60.0 ± 12.1 mg) was higher (P < .01) than saline (23.1 ± 1.6 mg) and batches I (37.6 ± 1.4 mg) and II (31.0 ± 4.3 mg). In experiment 2, the ovarian weight of rats treated with 30 IU of eCG of batch II (45.7 ± 4.1 mg) was higher (P < .01) than saline (32.6 ± 1.4 mg) and significantly lower (P = .05) than 10 UI of the standard WHO (63.3 ± 8.1 mg). Conclusion: The low ovarian response to eCG treatments can be related to differences in the physicochemical profile of eCG batches and RP-HPLC is a fast and reliable tool for detecting these differences.

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  • IPEN-DOC 23165

    FEITOSA, SABRINA A.; LIMA, NELSON B. ; YOSHITO, WALTER K. ; CAMPOS, FERNANDA; BOTTINO, MARCO A.; VALANDRO, LUIZ F.; BOTTINO, MARCO C.. Bonding strategies to full-contour zirconia: Zirconia pretreatment with piranha solution, glaze and airborne-particle abrasion. International Journal of Adhesion and Adhesives, v. 77, p. 151-156, 2017. DOI: 10.1016/j.ijadhadh.2017.05.007

    Abstract: This study aimed to evaluate the effect of various zirconia surface pretreatments on the adhesion between full contour 3Y-TZP zirconia and glaze, and the shear bond strength (SBS) between glazed/3Y-TZP and resin cement. Specimens were allocated into groups: GL-glaze; AL+GL-sandblasting with Al2O3+GL; CJ+GL-tribochemical silica coating (Cojet (R)/CJ) + GL; PS+GL-piranha solution+GL; and CJ. Adhesion between 3Y-TZP and GL was evaluated using the scratch test. Surface topography and glaze thickness were evaluated by using a scanning electron microscope (SEM). For SBS, glazed/3Y-TZP surface was etched with hydrofluoric acid and a silane was applied. For CJ only the silane was applied. Samples were tested after 24 h (24 h wet) or after 15,000 thermal cycles and 90 days storage (thermocycled). After SBS, the type of failure was classified as: adhesive, mixed or cohesive. The data were analyzed using two-way ANOVA and Tukey's test. SEM analysis after scratch test revealed circular cracks in the GL group and conformal cracks in the others groups. SEM micrographs suggested that zirconia specimens submitted to airborne-particle abrasion presents rougher and porous surface when compared to surfaces treated with GL and PS. The glaze layer was approximately 1.86 mu m thick in all groups. After 24 h, SBS test showed highest values for AL + GL and CJ + GL and were significantly higher when compared to the GL group. Differences were not significant between PS + GL and the other groups. After aging (thermo-cycling + storage), groups GL and CJ presented no statistically significant difference compared to 24 h and aged AL+GL, CJ+GL and PS + GL groups. The predominant type of failure was mixed. 3Y-TZP surface treatment with glaze application could be considered as an alternative treatment, since it yielded a similar resin bond strength without the need for airborne-particle abrasion.

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  • IPEN-DOC 23158

    CARMO, FAGNER S. do; RICCI-JUNIOR, EDUARDO; CERQUEIRA-COUTINHO, CRISTAL; ALBERNAZ, MARTA de S.; BERNARDES, EMERSON S. ; MISSAILIDIS, SOTIRIS; SANTOS-OLIVEIRA, RALPH. Anti-MUC1 nano-aptamers for triple-negative breast cancer imaging by single-photon emission computed tomography in inducted animals: initial considerations. International Journal of Nanomedicine, v. 12, p. 53-60, 2017. DOI: 10.2147/IJN.S118482

    Abstract: The early and specific detection of tumors remains a barrier in oncology, especially in cases such as the triple-negative breast cancer (TNBC). To address this gap, aptamers have found an important application in the recognition of tumor biomarkers such as mucin 1 (MUC1). However, there are still some difficulties in the use of aptamer, as their rapid biological clearance makes their use as drugs limited. In this study, the anti-MUC1 aptamer was used as a drug delivery system (DDS) for a radioactive polymeric nanoparticle (NP) in the imaging of TNBCs. Thus, poly(lactic-co-glycolic acid) NPs loaded with the anti-MUC1 aptamer and labeled with technetium-99m were used for a biodistribution study and imaging of TNBC. The results confirmed that the NP was successfully obtained, with a mean size of 262 nm, according to the dynamic light scattering data. The biodistribution assay in induced animal models with TNBC showed that although there was a high capture by intestine (>30%), the DDS developed had a high tumor uptake (5%) and with great in vivo imaging properties, corroborating the possibility of use of this DDS as an imaging drug for TNBC.

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  • IPEN-DOC 23210

    SILVA, JULIO C.M. ; NTAIS, SPYRIDON; TEIXEIRA-NETO, ERICO; SPINACE, ESTEVAM V. ; CUI, XIAOYU; NETO, ALMIR O. ; BARANOVA, ELENA A.. Evaluation of carbon supported platinum-ruthenium nanoparticles for ammonia electro-oxidation: Combined fuel cell and electrochemical approach. International Journal of Hydrogen Energy, v. 42, n. 1, p. 193-201, 2017. DOI: 10.1016/j.ijhydene.2016.09.135

    Abstract: Ammonia electro-oxidation reaction (AmER) was investigated by using conventional electrochemical experiments, direct ammonia fuel cell (DAFC) and galvanostatic electrolysis experiments. The working electrode/anodes were composed of carbon supported PtRu/C nanoparticles (NPs) with atomic Pt:Ru ratios of 100:0, 90:10, 70:30 and 50:50. The resulting nanoparticles ranged between 5.1 and 7.3 nm in size depending on the Ru content and were analyzed by XRD, TEM and synchrotron radiation photoelectron Spectroscopy (SRPES). Alloying Pt with Ru shifted AmER to the lower onset potentials compared to Pt/C. Among nanostructured PtRu/C electrocatalysts, the Pt90Ru10 composition showed the best activity and stability in the conventional electrochemical (cyclic voltammetry and chronoamperometry) experiments, DAFC and 8 h galvanostatic electrolysis. The concentration of nitrite and nitrate was doubled using PtRu/C 90:10 compared to Pt/C, because of excess of OHads species formed on Ru. The results show that the addition of small amount of Ru to Pt NPs improves the AmER due to additional formation of OHads that promote the reaction on alloyed PtRu nanoparticles. Crown Copyright (C) 2016 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. All rights reserved.

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  • IPEN-DOC 23131

    CARVALHO, C.N.; WANG, Z.; SHEN, Y.; GAVINI, G.; MARTINELLI, J.R. ; MANSO, A.; HAAPASALO, M.. Comparative analyses of ion release, pH and multispecies biofilm formation between conventional and bioactive gutta-percha. International Endodontic Journal, v. 49, n. 11, p. 1048-1056, 2016. DOI: 10.1111/iej.12558

    Abstract: AimTo analyse the effect of commercial and experimental gutta-percha with the addition of niobium phosphate glass on biofilm formation by oral bacteria from human dental plaque. Additional pH and elemental release of the materials were analysed. MethodologyThe multispecies biofilm was grown anaerobically from plaque bacteria on standardized discs of each material: hydroxyapatite (HA), gutta-percha pellets (OBT) (Obtura pellets, Shoreline, CT, USA), ProTaper gutta-percha (PTP) (ProTaper Universal Gutta-Percha Points, Dentsply Maillefer, Ballaigues, Switzerland), EndoSequence BC gutta-percha (GBC) (Brasseler USA, Savannah, GA, USA), experimental gutta-percha associated with niobium phosphate glass (GNB) and niobium phosphate glass (NPG). Specimens (n=5 per group and per incubation period) were incubated in brain-heart infusion broth for 3, 14 and 30days, at 37 degrees C, and stained using live/dead viability assay. Images were analysed by confocal laser scanning microscopy (CLSM) and the total biovolume (mm(3)), viable bacteria biovolume (mm(3)), and live percentage (%) were quantified. For pH measurement, specimens of each material (n=3) were immersed in phosphate-buffered saline at 37 degrees C, and pH was monitored in multiple intervals, up to 30days. For elemental analysis, additional specimens (n=3) were immersed in deionized water and elemental release was analysed by ICP-OES (inductively coupled plasma - optical emission spectrometry) at time intervals of 3, 14 and 30days. Differences between groups were evaluated by the two-way analysis of variation (anova) with Tukey's post hoc test (P<0.05). ResultsThe lowest total biovolume at 30days was found in GNB, GBC and NPG. GNB had the lowest viable bacteria biovolume (mean value) at 30days (P<0.05), and the lowest live percentage of bacteria at 3 and 30days (P<0.05), whilst NPG had the lowest live percentage at 14days (P<0.05). GNB had the highest pH (8.45) after 30days (P<0.05), and the greatest Zn and Na release at all time intervals (P<0.05). Both GBC and GNB had significantly higher Ca release at 14 and 30days. ConclusionGNB and GBC reduced biofilm formation, GNB had the lowest amount of viable bacteria in biofilms with the highest pH, and high Zn and Na release values after 30days.

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  • IPEN-DOC 23202

    SCHELL, JULIANA; LUPASCU, DORU C.; CORREIA, JOAO G.M.; CARBONARI, ARTUR W. ; DEICHER, MANFRED; BARBOSA, MARCELO B.; MANSANO, RONALDO D.; JOHNSTON, KARL; RIBEIRO JUNIOR, IBERE S. . In and Cd as defect traps in titanium dioxide. Hyperfine Interactions, v. 238, n. 2, 2017. DOI: 10.1007/s10751-016-1373-7

    Abstract: We present a study of TiO2 single crystals from the point of view of the dopant atom that simultaneously behaves as the probing element. We used gamma-gamma time dependent perturbed angular correlations working with selected tracer elements (In-111/Cd-111, Cd-111m/Cd-111) together to investigate the different behavior of Cd and In dopants, particularly their interaction with point defects in the TiO2 lattice. Results show that the hyperfine interactions observed at Cd-111 from In-111 or Cd-111m decay are quite different. In-111/Cd-111 results show a single site fraction characterized by a quadrupole frequency with asymmetry parameter similar to those observed for the same probe nuclei in bulk TiO2 oxides. Results for Cd-111m/Cd-111 reveal two site fractions, one characterized by the same hyperfine parameters to those measured in bulk TiO2 and another fraction characterized by a quadrupole frequency and asymmetry parameters with higher values, as observed in thin TiO2 films and correlated with point defects. The results are discussed emphasizing the differences for Cd and In as defect traps on TiO2.

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  • IPEN-DOC 23187

    PAULINO, A.L.R.; CUNHA, E.F. ; ROBALINHO, E.; LINARDI, M. ; KORKISCHKO, I.; SANTIAGO, E.I. . CFD analysis of PEMFC flow channel cross sections. Fuel Cells, v. 17, n. 1, p. 27-36, 2017. DOI: 10.1002/fuce.201600141

    Abstract: This paper presents a study of single-channel proton exchange membrane fuel cells (PEMFCs) using computational modeling and simulation. For this analysis, the commercial software COMSOL Multiphysics was used to build a single-phase isothermal and tridimensional fuel cell model. For the mathematical description of the catalyst layer, the flooded agglomerate model was implemented, and it proved to be more accurate than Butler-Volmer model, which is the pre-built model in the software. Such evidence was verified when comparing the polarization curves obtained using both models with an experimental curve. After definition of the model, the main objective of this study was to analyze the influence of the flow channel cross-section in the water distribution inside the cell, studying rectangular, trapezoidal and hybrid stepped geometries. The fuel cell with stepped channel was equivalent to the trapezoidal cell in all aspects analyzed, and both provided superior water management than the rectangular cell. However, the current generation in the rectangular design was slightly higher. It was noted that the simulation of a tridimensional model provided a better understanding of the regions where higher concentrations of water can occur, and that different flow channel designs can be used to enhance water management.

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  • IPEN-DOC 23214

    VALGODE, FLAVIA G.S. ; SILVA, MARCIA A. da ; VIEIRA, DANIEL P. ; RIBELA, MARIA T.C.P. ; BARTOLINI, PAOLO ; OKAZAKI, KAYO . Cytotoxic and genotoxic effects of I-131 and Co-60 in follicular thyroid cancer cell (WRO) with and without recombinant human thyroid-stimulating hormone treatment. Environmental and Molecular Mutagenesis, v. 58, n. 6, p. 451-461, 2017. DOI: 10.1002/em.22099

    Abstract: Normally, differentiated thyroid cancer (DTC) tends to be biologically indolent, highly curable and has an excellent prognosis. However, the treatment may fail when the cancer has lost radioiodine avidity. The present study was carried out in order to evaluate the cytotoxic and genotoxic effects of I-131 and Co-60 and radioiodine uptake in WRO cells, derived from DTC, harboring the BRAF(V600E) mutation. WRO cells showed a relatively slow cell cycle of 96.3 h with an unstable karyotype containing various double minutes. The genotoxicity assay (micronucleus test) showed a relative high radioresistance to I-131 (0.07-3.70 MBq/mL), independent of treatment with recombinant human thyroid-stimulating hormone (rhTSH). For the cytotoxicity assay, WRO cells were also relatively resistant to Co-60 (range: 0.2-8.3 Gy), but with a gradual decrease of viability as a function of time for higher doses (20 and 40 Gy, starting from the fifth to sixth day). For internal irradiation with I-131, WRO cells showed a decline in viability at radioactive concentration higher than 1.85 MBq/mL; this was even more effective at 3.70 MBq/mL, but only when preceded by rhTSH, in coincidence with the highest level of I-131 uptake. These data show promising results, since the loss of the ability of thyroid cells to concentrate radioiodine is considered to be one of the main factors responsible for the failure of I-131 therapy in patients with DTC. The use of tumor-derived cell lines as a model for in vivo tumor requires, however, further investigations and deep evaluation of the corresponding in vivo effects.

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  • IPEN-DOC 23159

    CONTI, THADEU das N. ; CABRAL, EDUARDO L.L.; SABUNDJIAN, GAIANE . Application of the hierarchical functions expansion method for the solution of the two dimensional navier-stokes equations for compressible fluids in high velocity. Energy and Power Engineering, v. 9, n. 2, 2017. DOI: 10.4236/epe.2017.92007

    Abstract: This work presents a new application for the Hierarchical Function Expansion Method for the solution of the Navier-Stokes equations for compressible fluids in two dimensions and in high velocity. This method is based on the finite elements method using the Petrov-Galerkin formulation, know as SUPG (Streamline Upwind Petrov-Galerkin), applied with the expansion of the variables into hierarchical functions. To test and validate the numerical method proposed as well as the computational program developed simulations are performed for some cases whose theoretical solutions are known. These cases are the following: continuity test, stability and convergence test, temperature step problem, and several oblique shocks. The objective of the last cases is basically to verify the capture of the shock wave by the method developed. The results obtained in the simulations with the proposed method were good both qualitatively and quantitatively when compared with the theoretical solutions. This allows concluding that the objectives of this work are reached.

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  • IPEN-DOC 23157

    CANTINHA, REBECA da S. ; BORRELY, SUELI I. ; OGUIURA, NANCY; PEREIRA, CARLOS A. de B.; RIGOLON, MARCELA M.; NAKANO, ELIANA. HSP70 expression in Biomphalaria glabrata snails exposed to cadmium. Ecotoxicology and Environmental Safety, v. 140, p. 18-23, 2017. DOI: 10.1016/j.ecoenv.2017.02.026

    Abstract: In this study, the effects of the heavy metal cadmium on the stress protein HSP70 are investigated in freshwater mollusks Biomphalaria glabrata. Adult snails were exposed for 96 h to CdCl2 at concentrations ranging from 0.09 to 0.7 mg L-1 (LC50/96 (h) = 0.34 (0.30-0.37). Time and concentration-dependent increases in the expression of HSP70 were observed at sub-lethal levels in the immunoblotting assay. Further, an increased survival to a lethal heat shock was observed in animals pre-exposed to a nonlethal concentration of cadmium, evidencing the induction of acquired tolerance. The present study demonstrated the inducibility of B. glabrata HSP70 by cadmium, a relevant environmental contaminant, at non-lethal levels, providing evidences that the assessment of HSP70 in B. glabrata can be regarded as a suitable biomarker for ecotoxicological studies.

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  • IPEN-DOC 23182

    MOREIRA, LUCAS B.; CASTRO, ITALO B.; HORTELLANI, MARCOS A. ; SASAKI, SILVIO T.; TANIGUCHI, SATIE; PETTI, MONICA A.V.; FILLMANN, GILBERTO; SARKIS, JORGE E.S. ; BICEGO, MARCIA C.; COSTA-LOTUFO, LETICIA V.; ABESSA, DENIS M.S.. Effects of harbor activities on sediment quality in a semi-arid region in Brazil. Ecotoxicology and Environmental Safety, v. 135, p. 137-151, 2017. DOI: 10.1016/j.ecoenv.2016.09.020

    Abstract: Tropicalmarineenvironmentsarerichinbiodiversityandthepresenceofharboractivitiesintheseareas can harmthecoastalecosystems.Inthisstudy,weassessedsedimentqualityoftwoharborsfroma tropical regioninBrazilbyapplyingmultiplelines-of-evidenceapproach.Thisapproachincludedthe integrationofresultson:(1)grainsize,organicmatter,organiccarbon,nitrogen,phosphorus,trace metals, polycyclicaromatichydrocarbons,linearalkylbenzenes,andtributyltin;(2)acutetoxicityof whole sedimentsandchronictoxicityofliquidphases;and(3)benthiccommunitydescriptors.Our results revealedthatthemaincontaminantsdetectedinsedimentsfromMucuripeandPecémHarbors werechromium,copper,nitrogen,zinc,andtributyltin.Thesetoxicantsarisefromtypicalharboractiv- ities. However,thechangesinbenthiccompositionandstructureappeartodependonacombinationof physicalimpacts,suchasthedepositionof fine sedimentsandthetoxicpotentialofcontaminants, especially inMucuripe.Thus,apartfromtoxicantsphysicalprocessesareimportantindescribingrisks. This informationmayassistinmanagementandconservationofmarinecoastalareas.

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  • IPEN-DOC 23178

    MARTINI, G.A.; ROGERO, S.O. ; ROGERO, J.R. . Cytotoxic effects caused by N,N-diethyl-meta-toluamide and radiation in Perna perna mussels. Ecotoxicology and Environmental Contamination, v. 12, n. 1, p. 33-37, 2017. DOI: 10.5132/eec.2017.01.05

    Abstract: The aim of this study was to evaluate the biological effects of ionizing radiation in combination with DEET on marine aquatic biota. It was studied the exposure of irradiated and non-irradiated marine mussels to different concentrations of DEET. It was compared the recoverability of mussels which were exposed to DEET after suffering another stressful action by the ionizing radiation. The cytotoxicity by the neutral red retention time assay was used to verify the DEET effect on the lysosomal membrane of Perna perna mussels hemocytes in non-irradiated and irradiated organisms. The organisms were irradiated at 3, 11 and 107 Gy doses of 60Co gamma rays and exposed to 0.1; 1.0 and 20.0 μg L-1 DEET. The results were obtained 24, 48 and 72h after irradiation. It was observed statistic significance at concentrations of 1.0 and 20.0 μg L-1 in non-irradiated mussels for all exposure times. In mussels irradiated with 3 Gy and 11 Gy it was observed that the retention time was not significantly different from trials in which the organisms were not irradiated. The 107 Gy dose caused some adverse effects to organisms showing a significant reduction in the number of cells compared with the other doses. The present study showed cytotoxic effect of DEET to Perna perna mussels at concentrations above 0.1 μg L-1 a value very close to the concentrations identified in the environment suggesting attention to this concentration range.

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  • IPEN-DOC 23166

    FERREIRA, EDUARDO G.A. ; YOKAICHYIA, FABIANO; RODRIGUES, MICHELLE S.; BERALDO, ANTONIO L.; ISAAC, AUGUSTA; KARDJILOV, NIKOLAY; FRANCO, MARGARETH K.K.D. . Assessment of Greener Cement by employing thermally treated sugarcane straw ashes. Construction and Building Materials, v. 141, p. 343-352, 2017. DOI: 10.1016/j.conbuildmat.2017.03.022

    Abstract: Sustainable development has been growing concern worldwide, with special emphasis to its effects on climate change. An important action to reduce the environmental damage is the decrease of cement use. In this study the pozzolanicity of Sugarcane Straw Ashes (SCSA), thermal treated, at different curing times was investigated. Synchrotron X-ray Powder Diffraction measurements allowed the quantification of several phases of the cement pasts through Rietveld analysis. The properties of cement paste are directly related to the concentrations of Alite, Belite, Portlandite, Brownmilite and amorphous phases. Tomography technique was also used to study the differences amongst the pore structures according to type of ash used. The SCSA substitution of 20% (weight) in Ordinary Portland Cement (OPC) shows to be a good option to recover the agroindustrial wastes.

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  • IPEN-DOC 23171

    GROSSO, ROBSON L. ; REIS, S.L. ; MUCCILLO, E.N.S. . Improved ionic conductivity of zirconia-scandia with niobia addition. Ceramics International, v. 43, n. 14, p. 10934-10938, 2017. DOI: 10.1016/j.ceramint.2017.05.131

    Abstract: The ionic conductivity and the crystalline structure of ZrO2−10 mol% Sc2O3- x mol% Nb2O5 solid electrolytes were investigated for x=0.25, 0.5 and 1. Dense specimens with relative densities higher than 95% were prepared by solid state reaction and sintered at 1500 °C for 5 h. Full stabilization of the cubic structure at room temperature was obtained for compounds with x=0.5 and 1, whereas the cubic and rhombohedric structures coexist for x=0.25. The highest ionic conductivity in codoped system was found for specimen containing 0.5 mol % niobium pentoxide, with the same order of magnitude as that of the parent solid electrolyte (zirconia-10 mol % scandia) in the high temperature range (above 600 °C). Preliminary investigation on phase stability shows that the isothermal conductivity of the new solid electrolyte remained constant up to 100 h at 600 °C. Niobium pentoxide addition was found to improve the overall ionic conductivity of zirconia-scandia solid electrolyte.

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  • IPEN-DOC 23161

    CUESTA, ANA; ICHIKAWA, RODRIGO U. ; LONDONO-ZULUAGA, DIANA; DE LA TORRE, ANGELES G.; SANTACRUZ, ISABEL; TURRILLAS, XAVIER; ARANDA, MIGUEL A.G.. Aluminum hydroxide gel characterization within a calcium aluminate cement paste by combined Pair Distribution Function and Rietveld analyses. Cement and Concrete Research, v. 96, p. 1-12, 2017. DOI: 10.1016/j.cemconres.2017.02.025

    Abstract: There are many commercially importantmultiphasematerialswhich contain amorphous phases, such as cement pastes, porcelains, glass-ceramics or pharmaceutical compounds. However, the analysis of amorphous phase(s) within cement matrices that contain high amounts of crystalline phase(s) is a challenge. Here, we report measurements of total scattering data quantitatively analyzed by Pair Distribution Function (PDF) minimization and Rietveld methodology to determine phase compositions including both amorphous and nanocrystalline phase contents in cement-related samples. Furthermore, laboratory techniques were used to complement the sample characterization. In addition to five reference materials, the main phase of calcium aluminate cements, CaAl2O4 hydrated at 50 °C to yield crystalline hydrogarnet, Ca3Al2(OH)12, (43wt%) and nanocrystalline aluminum hydroxide gel, Al(OH)3·0.1H2O (50wt%)was also investigated. The PDF analyses revealed that the hydroxide gel has a gibbsite local structurewith an average particle size close to 5 nm. PDF and Rietveld quantitative phase analysis results fully agree.

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  • IPEN-DOC 23195

    SANTOS, W.S. ; NEVES, L.P.; PERINI, A.P.; BELINATO, W.; MAIA, A.F.; CALDAS, L.V.E. . Avaliação das exposições dos envolvidos em procedimentos intervencionistas usando método Monte Carlo. Brazilian Journal of Radiation Sciences, v. 5, n. 1, p. 01-06, 2017.

    Abstract: Neste estudo apresenta-se um modelo computacional de exposição de um paciente, médico cardiologista e de uma enfermeira em um cenário típico de procedimentos intervencionistas cardíacos. Neste caso, foi calculado um conjunto de coeficientes de conversão (CC) para dose efetiva (E) em termos do produto kerma-área (PKA) para os indivíduos envolvidos, utilizando sete espectros energéticos diferentes e oito projeções de feixe. Também foi calculado o CC para dose de entrada na pele (DEP) do paciente normalizado pelo PKA. Todos os indivíduos foram representados por simuladores antropomórficos computacionais incorporados em um código de transporte de radiação baseado em simulação de Monte Carlo.

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  • IPEN-DOC 23142

    SCHMIDT, CHRISTIAN; YOKAICHYIA, FABIANO; DOGANGUZEL, NURDAN; FRANCO, MARGARETH K.K.D. ; CAVALCANTI, LEIDE P.; BROWN, MARK A.; ALKSCHBIRS, MELISSA I.; ARAUJO, DANIELE R. de; KUMPUGDEE-VOLLRATH, MONT; STORSBERG, JOACHIM. An abraded surface of doxorubicin-loaded surfactant-containing drug delivery systems effectively reduces the survival of carcinoma cells. v. 4, n. 3, 2016. DOI: 10.3390/biomedicines4030022

    Abstract: An effective antitumor remedy is yet to be developed. All previous approaches for a targeted delivery of anticancer medicine have relied on trial and error. The goal of this study was to use structural insights gained from the study of delivery systems and malignant cells to provide for a systematic approach to the development of next-generation drugs. We used doxorubicin (Dox) liposomal formulations. We assayed for cytotoxicity via the electrical current exclusion method. Dialysis of the samples yielded information about their drug release profiles. Information about the surface of the delivery systems was obtained through synchrotron small-angle X-ray scattering (SAXS) measurements. SAXS measurements revealed that Dox-loading yielded an abraded surface of our Dox liposomal formulation containing soybean oil, which also correlated with an effective reduction of the survival of carcinoma cells. Furthermore, a dialysis assay revealed that a higher burst of Dox was released from soybean oil-containing preparations within the first five hours. We conclude from our results that an abraded surface of Dox-loaded drug delivery system increases their efficacy. The apparent match between surface geometry of drug delivery systems and target cells is suggested as a steppingstone for refined development of drug delivery systems. This is the first study to provide a systematic approach to developing next-generation drug carrier systems using structural insights to guide the development of next-generation drug delivery systems with increased efficacy and reduced side effects.

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  • IPEN-DOC 23209

    SILVA, REGIANE M. da; KO, GUI MI; SILVA, RINALDO F.; VIEIRA, LUDMILA C. ; PAULA, RAFAEL V. de; MARUMO, JULIO T. ; IKEGAMI, AMANDA ; BELLINI, MARIA H. . Essential elements as biomarkers of acute kidney injury and spontaneous reversion. Biological Trace Element Research, 2017. DOI: 10.1007/s12011-017-1091-2

    Abstract: Acute kidney injury (AKI) is an important health problem and can be caused by number of factors. The use of aminoglycosides, such as gentamicin, is one of these factors. Recently, an effort has been made to find biomarkers to guide treatment protocols. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to estimate the contents of Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn in serum and urine of the healthy, AKI, and spontaneous recovery (SR) groups of animals. The animal model of AKI and SR was validated by measuring serum and urinary urea and creatinine. The quantitative determination of the elements showed a decrease in serum levels of Ca, and Fe in the AKI group (P<0.01 vs. healthy), with a return to normal levels in the SR group, without a significant difference between the healthy and SR groups. In the urine samples, there was a decrease in P and Na levels in the AKI group (P<0.001 and P<0.01 vs. healthy), but Ca levels were increased in this group compared with the healthy and SR groups (P<0.01). These findings indicate that mineral elements might be useful as biomarkers for AKI.

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  • IPEN-DOC 23155

    BRAVO-ARANDA, JUAN A.; MOREIRA, GREGORI de A. ; NAVAS-GUZMAN, FRANCISCO; GRANADOS-MUNOZ, MARIA J.; GUERRERO-RASCADO, JUAN L.; POZO-VAZQUEZ, DAVID; ARBIZU-BARRENA, CLARA; REYES, FRANCISCO J.O.; MALLET, MARC; ARBOLEDAS, LUCAS A.. A new methodology for PBL height estimations based on lidar depolarization measurements: analysis and comparison against MWR and WRF model-based results. Atmospheric Chemistry and Physics, v. 17, n. 11, p. 6839-6851, 2017. DOI: 10.5194/acp-17-6839-2017

    Abstract: The automatic and non-supervised detection of the planetary boundary layer height (z(PBL)) by means of lidar measurements was widely investigated during the last several years. Despite considerable advances, the experimental detection still presents difficulties such as advected aerosol layers coupled to the planetary boundary layer (PBL) which usually produces an overestimation of the z(PBL). To improve the detection of the z(PBL) in these complex atmospheric situations, we present a new algorithm, called POLARIS (PBL height estimation based on lidar depolarisation). POLARIS applies the wavelet covariance transform (WCT) to the range-corrected signal (RCS) and to the perpendicular-to-parallel signal ratio (delta) profiles. Different candidates for z(PBL) are chosen and the selection is done based on the WCT applied to the RCS and delta. We use two ChArMEx (Chemistry-Aerosol Mediterranean Experiment) campaigns with lidar and microwave radiometer (MWR) measurements, conducted in 2012 and 2013, for the POLARIS' adjustment and validation. POLARIS improves the z(PBL) detection compared to previous methods based on lidar measurements, especially when an aerosol layer is coupled to the PBL. We also compare the z(PBL) provided by the Weather Research and Forecasting (WRF) numerical weather prediction (NWP) model with respect to the z(PBL) determined with POLARIS and the MWR under Saharan dust events. WRF underestimates the z(PBL) during daytime but agrees with the MWR during night-time. The z(PBL) provided by WRF shows a better temporal evolution compared to the MWR during daytime than during night-time.

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  • IPEN-DOC 23137

    KOETHER, K.; LOURENCO, M.L.G.; ULIAN, C.M.V.; GONCALVES, R.S.; SUDANO, M.J.; CRUZ, R.K.S.; SIQUEIRA, E.R.; VELO, A.F. ; CHIACCHIO, S.B.. Análise da variabilidade da frequência cardíaca em cordeiros da raça Bergamácia, do nascimento aos 35 dias de idade / Analysis of heart rate variability in Bergamasca newborn lambs from birth at 35th days of age. Arquivo Brasileiro de Medicina Veterinária e Zootecnia, v. 68, n. 4, 2016. DOI: 10.1590/1678-4162-7803

    Abstract: A atividade do sistema nervoso autônomo sobre o coração pode ser verificada pela variabilidade da frequência cardíaca (VFC), método que quantifica e assim infere sobre a modulação autonômica cardíaca, refletindo o funcionamento do sistema nervoso autônomo. Durante o período neonatal, diferenças significativas no que se refere à maturação autonômica são descritas em diversas espécies. Embora a espécie ovina venha sendo utilizada como modelo experimental em diversos protocolos em neonatologia e cardiologia em humanos, estudos descritivos sobre a VFC utilizando animais saudáveis e não sedados são escassos na literatura. O objetivo do estudo foi descrever a VFC em cordeiros da raça Bergamácia durante os primeiros 35 dias de idade. Foram realizados exames eletrocardiográficos em 20 cordeiros da raça Bergamácia a partir do nascimento e semanalmente até o 35° dia de idade. A VFC foi analisada pelo intervalo RR normal (batimentos sinusais), pela frequência cardíaca, pelo índice de tônus vasovagal (iTVV), pela raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes (RMSSD) e pela raiz quadrada da somatória do quadrado das diferenças dos valores individuais em relação ao valor médio, dividido pelo número de iR-R em 90 segundos - VFC global (RMSM). Todos os parâmetros se alteraram ao longo das semanas. A frequência cardíaca média elevou-se entre o nascimento e os primeiros sete dias de idade, com decréscimo nas quatro semanas subsequentes, sendo o menor valor encontrado aos 35 dias de idade (145,63±37,80bpm). Entre 21, 28 e 35 dias de idade, o iTVV elevou-se significativamente, o RMSM a partir do 28º dia, e, aos 35 dias, o RMSSD, reflexo da ativação parassimpática, exibiu diferenças em relação aos momentos subsequentes. O início da predominância parassimpática, refletida nos índices da VFC, particularmente o iTVV, ocorre aos 21 dias de idade. A partir dos 35 dias de idade, os índices RMSM e RMSSD podem ser utilizados como marcadores fidedignos das mudanças nos efeitos simpático e parassimpático sobre o coração de cordeiros.

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  • IPEN-DOC 23174

    KINOSHITA, ANGELA; MOLLEMBERG, MICHELLE; SANTANA, WILLIAM; FIGUEIREDO, ANA M.G. ; GUIDON, NIEDE; LUZ, MARIA de F. da; GUERIN, CLAUDE; BAFFA, OSWALDO. ESR dating of Smilodon populator from Toca de Cima dos Pilão, Piauí, Brazil. Applied Radiation and Isotopes, v. 120, p. 66-70, 2017. DOI: 10.1016/j.apradiso.2016.11.016

    Abstract: Smilodon is a genus of big cats that lived from the early to the late Pleistocene in regions extending from North to South America. The fossil records of the "saber-toothed cats" are uneven, with some taxa being quite abundant in certain regions. In Brazil, Smilodon populator is a well-known species whose remains, although scarce in comparison to other large mammals, are found all across the country. In particular, there are multiple records of this species in the region of the Serra da Capivara National Park. This area was home to a rich Pleistocene-Holocene fauna, including many mammals. Here, we report on the Electron Spin Resonance dating of a Smilodon populator tooth found in "Toca de Cima dos Pilao", located in the surroundings of the Serra da Capivara National Park. The equivalent dose found after exponential fitting of dose-response curve was (2.7 +/- 0.3)x10(2) Gy. Neutron Activation Analysis was used to determine the concentration of radioisotopes present in the sample and in the sediment to calculate the internal and external dose rates. The result of age found is 93 +/- 9 ka, which confirmed the presence of this species in Serra da Capivara National Park in the late Pleistocene.

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  • IPEN-DOC 23211

    STEIL, M.C.; NOBREGA, S.D.; GEORGES, S.; GELIN, P.; UHLENBRUCK, S.; FONSECA, F.C. . Durable direct ethanol anode-supported solid oxide fuel cell. Applied Energy, v. 199, p. 180-186, 2017. DOI: 10.1016/j.apenergy.2017.04.086

    Abstract: Anode-supported solid oxide fuel cells accumulating more than 700 h of stable operation on dry ethanol with high current output are reported. A highly active ceria-based catalytic layer deposited onto the anode efficiently converts the primary fuel into hydrogen using the electrochemically generated steam. On the other hand, standard fuel cells without the catalytic layer collapse because of carbon deposit formation within the initial 5 h of operation with ethanol. The nanostructured ceria-based catalyst forms a continuous porous layer (similar to 25 mu m thick) over the Ni-based anode support that has no apparent influence on the fuel cell operation and prevents carbon deposit formation. Moreover, the catalytic layer promotes overall steam reforming reactions of ethanol that result in similar current outputs in both hydrogen and ethanol fuels. The stability of single cells, with relatively large active area (8 cm(2)), confirms the feasibility of a catalytic layer for internal reforming of biofuels in solid oxide fuel cells. The experimental results provide a significant step towards the practical application of direct ethanol solid oxide fuel cells.

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  • IPEN-DOC 23208

    SILVA, A.A.A. da; BION, N.; EPRON, F.; BARAKA, S.; FONSECA, F.C. ; RABELO-NETO, R.C.; MATTOS, L.V.; NORONHA, F.B.. Effect of the type of ceria dopant on the performance of Ni/CeO2 SOFC anode for ethanol internal reforming. Applied Catalysis B: Environmental, v. 206, p. 626-641, 2017. DOI: 10.1016/j.apcatb.2017.01.069

    Abstract: This work studied the effect of the type of ceria dopant on the performance of Ni/CeO2 SOFC anode for ethanol conversion reaction. Ni-based catalysts supported on CeO2 doped with different cations (Gd, Y, Pr, Zr, Nb) were prepared by the hydrothermal method. The addition of dopant to ceria led to the formation of the solid solutions during calcination for all samples, except for CeNb sample due to the low solubility limit. In spite of the high oxygen mobility of ceria-based supports, all catalysts deactivated for ethanol decomposition reaction at 1123 K due to carbon deposition. The large Ni-0 and CeO2 crystallites formed during calcination at high temperature reduced the effectiveness of the mechanism of carbon removal because of the low metal -support interfacial area. The lowest formation of carbon on Ni/CeNb catalyst was attributed to the presence of NiNb2O6 phase. The reduction of this phase leads to the formation of Ni particles covered by NbOx species, which inhibits carbon formation.(C) 2017 Elsevier B.V. All rights reserved.

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  • IPEN-DOC 23156

    BRAZ FILHO, FRANCISCO A.; SABUNDJIAN, GAIANE ; RIBEIRO, GUILHERME B.; CALDEIRA, ALEXANDRE D.. Assessment of RELAP5 matrix solvers for a two-phase natural circulation loop. Annals of Nuclear Energy, v. 105, p. 249-258, 2017. DOI: 10.1016/j.anucene.2017.03.023

    Abstract: The heat transfer mechanism of natural convection has been extensively studied as a passive heat removal system of new nuclear power plants. Considering this aspect, the main objective of this study is to present an assessment of RELAP5 linear-equation solver under a transient two-fluid model for a two-phase natural circulation loop (NCL). For this assessment, three different approaches of linearequation solvers for the hydrodynamic model are presented: the sparse matrix solver based on the Lower-Upper (LU) decomposition, the Border-Profile Lower Upper (BPLU) solver and the iterative method named Generalized Minimal Residual Method (GMRES). For comparison purposes, an experimental natural circulation loop made of glass tubes and using water as working fluid is analyzed. The onset of nucleate boiling observed during the experiment was predicted by all RELAP5 solvers as well as the representation of flow oscillations along the loop. Furthermore, it was noticed that the choice of the solver algorithm has a strong influence on the prediction of the two-phase natural circulation phenomena, since different wavelengths and amplitudes of flow instabilities were obtained for each approach.

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  • IPEN-DOC 23154

    BOSCH-SANTOS, B. ; CABRERA-PASCA, G.A.; SAXENA, R.N. ; FREITAS, R.S.; CARBONARI, A.W. . Characterization of magnetic phase transitions in PrMn2Ge2 compound investigated by magnetization and hyperfine field measurements. AIP Advances, v. 7, n. 5, p. 056211-1 - 056211-6, 2017. DOI: 10.1063/1.4974025

    Abstract: The magnetic properties of PrMn2Ge2 compound have been investigated by perturbed γ−γγ−γ angular correlation (PAC) spectroscopy using 111In(111Cd) as probe nuclei as well as by magnetization measurements. This ternary intermetallic compound exhibits different magnetic structures depending on the temperature. The magnetic ordering is mainly associated with the magnetic moment of 3d-Mn sublattice but at low temperatures a magnetic contribution due to ordering of the magnetic moment from 4f-Pr sublattice appears. PAC results with 111Cd probe nuclei at Mn sites show that the temperature dependence of hyperfine field Bhf(T) follows the expected behavior for the host magnetization, which could be fitted by two Brillouin functions, one for antiferromagnetic phase and the other for ferromagnetic phase, associated with the magnetic ordering of Mn ions. Magnetization measurements showed the magnetic behavior due to Mn ions highlighting the antiferromagnetic to ferromagnetic transition around 326 K and an increase in the magnetization around 36 K, which is ascribed to Pr ions ordering.

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  • IPEN-DOC 23201

    SCHELL, JULIANA; LUPASCU, DORU C.; CARBONARI, ARTUR W. ; MANSANO, RONALDO D.; DANG, THIEN T.; VIANDEN, REINER. Implantation of cobalt in SnO2 thin films studied by TDPAC. AIP Advances, v. 7, n. 5, p. 055304-1 - 055304-6, 2017. DOI: 10.1063/1.4983270

    Abstract: Here we report time differential perturbed angular correlation (TDPAC) results of Co-doped SnO2 thin films. Making use of stable Co and radioactive 111In implanted at the Bonn Radioisotope Separator with energies of 80 keV and 160 keV, respectively, it was possible to study the dopant incorporation and its lattice location during annealing. The hyperfine parameters have been probed as a function of temperature in vacuum. Two quadrupole interactions were observed. At high temperatures the dominant fraction for the probe nuclei can be assigned to the Cd-incorporation at the cation substitutional site in a highly disordered structure, obtained after implantation, to high crystallinity for the measurements at 873 K and 923 K. The similarity in TDPAC spectra obtained in undoped SnO gives indirect evidence that In and Co diffuse to different depths during the annealing process. Other interpretations will be discussed.

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  • IPEN-DOC 23213

    UEHARA, VANESSA B. ; MASTRO, NELIDA L. del . Characteristics of biodegradable films based on cassava starch and soy isolate protein treated by electron beam radiation. Academia Journal of Agricultural Research, v. 5, n. 4, p. 68-74, 2017. DOI: 10.15413/ajar.2017.0115

    Abstract: Polymers from renewable sources can fulfill in some aspects the needs of consumers without damaging the environment, health and economy. Soy protein concentrate and cassava starch may be considered an alternative to petrochemical polymers. Ionizing radiation processing with gamma rays or electron beam is currently used for the modification of polymers and macromolecules. The widely known ability of proteins and polysaccharides to form films as a starting point for the development of new materials aimed at edible packaging for the food industry was employed. Films based on cassava starch and isolated soy proteins were prepared in two different formulations and electron beam irradiated with 0, 20 and 40 kGy. The tensile strength decreased upon irradiation and yellow color intensified. Regarding thermal properties, no significant differences were observed between irradiated and non-irradiated samples. However, regarding properties such as water vapor permeability and water absorption, the films became less permeable at higher radiation doses. Films with good resistance to water vapor and low water absorption would be considered suitable for food packaging. Radiation seems a convenient tool for the modification of this kind of biopolymeric blends and opens a huge array of possibilities of application.

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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.

Repositórios Digitais Institucionais: a experiência

do Instituto de Pesquisas Energéticas e Nucleares

(IPEN)

Mery P. Zamudio Igami

Biblioteca Terezine Arantes Ferraz

1 Repositórios Digitais Institucionais – RDI

A tecnologia da informação modificou significativamente todas as atividades rotineiras da sociedade. O surgimento das redes de comunicação transformou o ambiente onde elas atuam mudando o conceito de espaço e tempo no âmbito da comunicação e informação pela instantaneidade da transmissão de dados.

Na área de comunicação científica não foi diferente. Toda a cadeia de produção, disseminação, publicação e armazenamento de documentos científicos experimentou uma grande transformação, impactando de forma positiva a produção e consumo da informação científica na área acadêmica. O surgimento da internet e da WWW, na década de 80, aceleraram as mudanças na forma de comunicar e disseminar os trabalhos acadêmicos que passaram do suporte exclusivamente em papel para o suporte digital.

Na mesma época houve uma significativa crise mundial devido aos altos preços praticados pelas editoras no processo de assinatura das publicações periódicas, tornando inviável a sustentação das coleções pelas bibliotecas e afetando diretamente a consulta pelos usuários. Como reação da própria comunidade científica surgiu então o movimento de livre acesso à informação científica, mais conhecido por Open Access Iniciative (KURAMOTO, 2012).

Esse movimento defende a disponibilização na internet da literatura acadêmica e científica permitindo que seja lida, descarregada, distribuída, impressa e pesquisada livremente.

É importante o registro histórico desse movimento não somente porque está diretamente relacionado à criação dos RDIs, mas também porque ele possibilitou várias mudanças estruturais no fluxo da comunicação científica. Os editores perderam a exclusividade de distribuição (comercialização) da pesquisa científica, uma vez que na era digital é possível que isso seja realizado de forma descentralizada e por iniciativa de cada autor.

1.1 O movimento do Open Access Iniciative - OAI

A partir de 1999, os movimentos em favor do acesso livre à literatura científica, principalmente à literatura produzida sob financiamento público, consolidaram-se.

A comunidade acadêmica envolvida nesses movimentos corroborou o seu apoio por meio de declarações formais, dentro das quais se destaca a Declaração de Budapest – BOAI –1 em 2002, onde foram emitidos os conceitos básicos do OAI, e a Declaração de Berlim2 em 2003, onde se destacou a natureza institucional dos repositórios digitais de livre acesso como um espaço organizado baseado em regras de utilização que conferem credibilidade aos materiais publicados e em políticas de arquivamento a longo prazo.

O movimento Open Archives Iniciative desenvolveu padrões de interoperabilidade buscando facilitar a comunicação eficiente de conteúdo. Foram também estabelecidas duas modalidades para viabilizar a disponibilidade dos conteúdos: a via verde que diz respeito ao autodepósito nos RDs e a via dourada que inclui as revistas que publicam os artigos com livre acesso.

O primeiro repositório digital (ArXiv.org )3 foi instalado no laboratório de física, em Los Álamos, EU, coordenado pelo físico Paul Ginsparg (1996), motivado pela insatisfação com os rumos na política de aquisição das publicações científicas e a crescente inviabilidade das bibliotecas americanas de manter as coleções atualizadas. Daquela época para a atual aconteceram inúmeras mudanças positivas nos modelos de funcionamento dos repositórios promovidas pela evolução da TI.

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1 Budapest Open Access Iniciative - http://www.budapestopenaccessinitiative.org

2 Open Access - http://openaccess.mpg.de/Berlin-Declaration

3 General Information about Arxiv - http://arxiv.org

Não existe um modelo único para a criação dos RDIs; cada instituição define a política de depósito adequada ao contexto da sua comunidade. O importante é que essa comunidade valide e utilize a plataforma tornando-a uma vitrine da sua produção científica.

No país, o movimento de Acesso Aberto e construção de Repositórios Digitais Institucionais tiveram um grande incentivo e apoio técnico do Instituto Brasileiro de Informação em Ciência e Tecnologia – (IBICT) (INSTITUTO BRASILEIRO DE CIÊNCIA E TECNOLOGIA, 2009). De acordo com o Diretório internacional de RDIs – o DOAR4, até o momento, há no país 153 repositórios digitais em funcionamento, dos quais a maioria é mantida pelas instituições onde a comunidade produz os trabalhos científicos. Desses RDIs, 74% utilizam o software Dspace5.

1.2 O Projeto de Lei sobre os Repositórios Digitais

Em 2007, foi apresentado o Projeto de Lei no senado PL1120/2007 (BRASIL, 2007), que torna obrigatório nas universidades e institutos de pesquisa o desenvolvimento e implantação de RDIs nas instituições de origem, bem como torna obrigatório o autodepósito da produção científica por parte dos seus pesquisadores. Além disso, o Projeto de Lei determina a formação de uma comissão de alto nível para discutir, propor e estabelecer uma política de livre acesso à informação científica. Além de simplesmente criar mecanismos de disseminação da informação científica, o Projeto propõe a criação de uma comissão para discutir políticas e estabelecer diretrizes a serem adotadas em nível nacional pelas instituições que produzem informação científica.

1.3 O que são os RDIs?

Os RDIs constituem atualmente um avanço na gestão do conhecimento intelectual. Podem receber diversas denominações tais como equipamentos institucionais, observatórios digitais, instrumentos ou ferramentas de gestão de conhecimento e outras.

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4 The Directory of Open Access Repositories – OpenDOAR - http://www.opendoar.org

5 Software livre para construção de Repositorios Institucionais Digitais (Dspace) - http://www.ibict.br/pesquisa-desenvolvimento-tecnologico-e-inovacao/Sistema-para-Construcao-de-Repositorios-Institucionais-Digitais

Um dos aspectos mais importantes dos RDIs é que eles estão inseridos na política institucional de gestão do conhecimento e são essencialmente instrumentos gerenciais de onde se obtém indicadores para auxiliar na gestão da política científica das instituições de pesquisa.

Sob a ótica documentária um RDI constitui um serviço de informação científica em ambiente digital, interoperável e de acesso aberto, dedicado ao gerenciamento da produção científica de uma instituição. Contempla a reunião, armazenamento, organização, preservação, recuperação e, sobretudo, a ampla disseminação e visibilidade da informação científica produzida na instituição.

1.3.1 O que caracteriza um repositório digital?

a) a organização, armazenamento, acesso e distribuição de documentos digitais;

b) a utilização de padrões abertos acessibilidade;

c) as funcionalidades que o software selecionado permite;

d) a utilização de metadados com padrão internacional – interoperabilidade;

e) o arquivo digital anexado;

f) o acesso de buscadores para elaboração de rankings internacionais - visibilidade;

g) o autodepósito dos trabalhos;

h) a monitoração, controle e elaboração de indicadores.

2 O RDI do IPEN

O prestígio de uma instituição de pesquisa está fortemente vinculado aos resultados dos elementos intangíveis, por exemplo, qualidade no ensino da pós-graduação, e tangíveis como os resultados da pesquisa, entre eles a Produção científica. Tradicionalmente, o IPEN, por meio da sua unidade de informação, mantém a sua produção científica organizada e atualizada desde sua criação em 1956. No entanto, devido ao avanço da tecnologia da informação, tornou-se necessário atualizar a plataforma gerenciadora dessa informação já armazenada, com a consequente modernização no processo de gestão do capital intelectual.

No decorrer de 2013, seguindo outras instituições no país, como por exemplo, a Universidade de São Paulo, a Universidade Estadual Paulista e a Universidade Estadual de Campinas, a Direção do IPEN decidiu criar o seu repositório, uma vez que a matéria prima para concretizar esta ação já se encontrava disponível e organizada de tal forma que se garantiria a sustentabilidade do RDI.

A política de gestão da produção científica é uma prática rotineira no IPEN. Diferentemente da maioria dos repositórios em funcionamento, o RDI do IPEN já nasce com um volume significativo de matéria-prima digital organizada, com políticas definidas de auto arquivamento e de preservação da produção científica.

Porém, o fator determinante de sucesso foi o modelo de indexação e organização dos documentos adotado pela biblioteca desde o início em 1976, quando ainda se constituía em uma base de dados referencial. Este fato facilitou o processo de migração e compatibilização dos metadados para o novo padrão internacional adotado, o Dublin Core, garantindo interoperabilidade com outros repositórios digitais, uma das principais características dos RDIs.

Em novembro de 2013, foram iniciados os trabalhos de construção do RDI do IPEN. Inicialmente foram programadas visitas do grupo de informática e da biblioteca a instituições com experiências bem-sucedidas, como, por exemplo, o Instituto de Pesquisas Espaciais – (INPE) em São José dos Campos e a Universidade de São Paulo- USP, com o objetivo de conhecer melhor o projeto de RDIs dessas instituições e selecionar o modelo mais adequado à realidade do IPEN.

As visitas técnicas embasaram a decisão de selecionar o software Dspace para confecção do repositório do IPEN. O Dspace é um software livre especializado no gerenciamento de repositórios resultante de um projeto colaborativo da MIT Libraries e da Hewlett-Packard Company, amplamente utilizado no mundo. No Brasil, graças ao incentivo do IBICT em Brasília, o DSpace é utilizado por 75% das instituições que possuem repositórios.

2.1 O processo de migração

Em dezembro de 2013, foi iniciado o processo de criação do novo repositório do IPEN, após um estudo preliminar do software e contratação de uma empresa para a capacitação das equipes da biblioteca e da informática.

Nos meses seguintes foram efetuados os testes de implantação do Dspace, configuração, desenho da nova arquitetura do banco de dados, compatibilização e criação de novos metadados, desenvolvimento de funcionalidades.

Na época, a produção científica contabilizada era de 19.200 itens. A migração gradual desses itens iniciou-se em julho de 2014.

Internamente, além de todas as funções inerentes e habituais a um repositório, o diferencial do RDI do IPEN diz respeito à integração com os dados registrados no sistema de informação gerencial e planejamento do instituto, o SIGEPI. Trata-se da uma funcionalidade especial, desenvolvida em ambiente externo ao Dspace, porém acrescentada no momento do registro do documento no Dspace via metadado específico, de tal forma que cada trabalho registrado no RD se correlaciona, automaticamente com a atividade do Plano Diretor à qual o autor do IPEN está vinculado.

Para essa finalidade foi efetuado um exaustivo trabalho de identificação dos nomes completos dos autores do IPEN (lista de autoridades), com as suas respectivas variáveis na forma de citação e agrupamento dos trabalhos. Foi atribuído um número único de identificação para cada autor, o ID autor IPEN, formato semelhante ao Researcher ID utilizado pela base internacional Web of Science. Essa facilidade constituiu um filtro que ao ser acionado reúne e apresenta rapidamente todos os trabalhos de um determinado autor.

Ao RDI está vinculada também uma tabela estatística, atualizada on-line a cada registro introduzido. Essa funcionalidade destina-se à obtenção de dados para a elaboração de índices e quadros estatísticos a serem confeccionados fora do ambiente do Dspace para subsidiar os pesquisadores e os gestores do IPEN, com informações para a monitoração, administração e elaboração de indicadores científicos fornecidos para o Plano Diretor do IPEN, o relatório anual da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior( CAPES) e outros, bem como para cumprir as exigências dos órgãos financiadores de pesquisa.

O modelo adotado para a coleta dos trabalhos também difere de outros. Nesta primeira etapa foi considerado mais conveniente o serviço de informação (biblioteca) responsabilizar-se pela coleta, depósito e complementação dos dados, utilizando as fontes de informação nacionais e internacionais. Assim, a unidade de informação realiza periodicamente a verificação dos trabalhos publicados pelos pesquisadores nas bases Web of Science, Scopus, Scielo, INIS e Currículo Lattes. Após a eliminação das duplicatas e localização dos documentos na íntegra efetua-se o depósito no RDI.

Trata-se de um modelo de depósito que esta sendo testado, há vantagens e desvantagens. A principal vantagem diz respeito à economia de tempo do pesquisador uma vez que se elimina a obrigatoriedade do autodeposito, tornando, porém, imprescindível por parte do pesquisador à atualização do seu Currículo Lattes. A maior desvantagem foi absorvida pela Biblioteca, qual seja a coleta periódica dos documentos publicados bem como a localização e obtenção da evidência dos mesmos.

Importante registrar que a construção do RD foi uma iniciativa muito nova na instituição, que demandou um trabalho detalhado, cuidadoso e gradual das equipes de desenvolvimento de sistemas e da biblioteca, dado a pouca familiaridade com a nova plataforma. Alia-se a esse fato a opção de utilizar um software livre, onde certas funcionalidades ainda não foram desenvolvidas.

Em setembro de 2014, após oito meses de trabalho, as equipes conseguiram migrar 23%, das coleções, foi uma tarefa que demandou ajustes, adequações, testes e decisões internas, dado o grande nível de detalhamento dos dados, motivo de comemoração das equipes, após cada etapa finalizada e bem sucedida. Contamos também com a assessoria de uma empresa especializada no assunto, a qual guiou a equipe da informática em cada funcionalidade desenvolvida. Nesse ritmo de trabalho, foi possível completar o processo de migração em fevereiro de 2015. Finalmente, em junho desse mesmo ano, o RDI foi disponibilizado na Internet.

2.2 Desempenho do RDI em 2015

Atualmente o novo RDI:

- dispõe de uma identidade própria e permanente, (ex: http://repositorio.ipen.br );

- utiliza as estatísticas de uso do Google Analytics;

- é reconhecido pelo Google Scholar e outras máquinas de busca da Internet;

- participa dos rankings internacionais de repositórios institucionais (Ex: Webometrics);

- tem registro nos Diretórios Internacionais de RIs (Ex. DOAR);

- interopera com sistemas congêneres.

Conforme foi mencionado, a criação do RDI e a migração dos dados constitui a primeira etapa dentro de um projeto maior, qual seja institucionalizar e operacionalizar a gestão da produção científica do IPEN. Após o processo se consolidar em entrar em rotina de funcionamento, as próximas etapas a serem desenvolvidas pelas equipes, dizem respeito à:

- automação da coleta dos documentos;

- otimização das ferramentas de busca;

- obtenção de relatórios estatísticos customizados;

- otimização do lay-out do RDI;

- acréscimo de novas coleções;

- desenvolvimento de novas funcionalidades.

A pesquisa no RDI é muito simples e segue os padrões da maioria das bases de dados. É possível pesquisar por autor, título, assunto, ID de autor IPEN, ano de publicação, combinar palavras- chave de busca e assim por diante. Apresenta também uma tabela estatística funcionando em tempo real, distribuída por nível monográfico; isso permite que a direção e o corpo técnico científico acompanhe a evolução quantitativa dos documentos depositados no RDI.

Uma das últimas funcionalidades acrescentadas ao RD, diz respeito à sinalização dos autores do IPEN. Ao clicar no símbolo do autor é possível acessar a página do pesquisador, onde se apresentam os seguintes dados: as variáveis do nome, uma tabela com todos os trabalhos constantes no RDI , bem como um quadro resumo numérico. Dessa forma o autor pode visualizar, acessar e monitorar à sua produção científica com o texto completo de forma rápida e simples . O quadro resumo se configura ainda como uma linha do tempo para o autor.

Por se constituir em um equipamento totalmente apoiado na tecnologia da informação, o RDI é um recurso institucional dinâmico sujeito a constantes atualizações e melhorias, o qual deve garantir a confiabilidade dos dados providos bem como assegurar a sua sustentabilidade.

3 Referências bibliográficas

BRASIL. Projeto de Lei do Senado 1120/2007 Dispõe sobre o processo de disseminação da produção técnico-científica pelas instituições de ensino superior no Brasil e dá outras providências. Diário oficial da Republica Federativa , Brasília, DF, Disponível em: http://www.camara.gov.br/sileg/integras/461698.pdf Acesso em: set. 2014.

INSTITUTO BRASILEIRO DE INFORMAÇÃO EM CIÊNCIA E TECNOLOGIA - IBICT Repositórios digitais. Site institucional. Brasília: 2009. Disponível em: http://www.ibict.br/informacao-para-ciencia-tecnologia-e-inovacao%20/repositorios-digitais Acesso em set. 2014.

KURAMOTO, H. Acesso livre: como tudo começou. Brasília, 2012. Blog. Disponível em: http://kuramoto.blog.br/2012/02/27/acesso-livre-como-tudo-comecou Acesso em: set. 2014.

SP, janeiro de 2016