Abstract: Introduction: Functionalization of water-soluble chitosan (WSCS) nanocolloids with, gold nanoparticles (AuNPs), and LyslLys3 (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-bombesin 1– 14 (DOTA-BBN) peptide affords an innovative pathway to produce prostate tumor cell-specific nanomedicine agents with potential applications in molecular imaging and therapy. Methods: The preparation involves the production and full characterization of water-soluble chitosan (WSCS), via gamma (γ) rays (80 kGy) irradiation, followed by DOTA-BBN conjugation for subsequent use as an effective template toward the synthesis of tumor cell-specific AuNPs-WSCS-DOTA-BBN. Results: The WSCS-DOTA-BBN polymeric nanoparticles (86 ± 2.03 nm) served multiple roles as reducing and stabilizing agents in the overall template synthesis of tumor cell-targeted AuNPs. The AuNPs capped with WSCS and WSCS-DOTA-BBN exhibited average Au-core diameter of 17 ± 8 nm and 20 ± 7 nm with hydrodynamic diameters of 56 ± 1 and 67± 2 nm, respectively. The AuNPs-WSCS-DOTA-BBN showed optimum in vitro stability in biologically relevant solutions. The targeted AuNPs showed selective affinity toward GRP receptors overexpressed in prostate cancer cells (PC-3 and LNCaP). Discussion: The AuNPs-WSCS-DOTA-BBN displayed cytotoxicity effects against PC-3 and LNCaP cancer cells, with concomitant safety toward the HAECs normal cells. The AuNPs-WSCS-DOTA-BBN showed synergistic targeting toward tumor cells with selective cytotoxicity of AuNPs towards PC-3 and LNCaP cells. Our investigations provide compelling evidence that AuNPs functionalized with WSCS-DOTA-BBN is an innovative nanomedicine approach for use in molecular imaging and therapy of GRP receptor-positive tumors. The template synthesis of AuNPs-WSCS-DOTA-BBN serves as an excellent non-radioactive surrogate for the development of the corresponding 198AuNPs theragnostic nanoradiopharmaceutical for use in cancer diagnosis and therapy.

Palavras-Chave: nanoparticles; gold; prostate; neoplasms; radiopharmaceuticals; therapy; aqueous solutions; chitin

TANGTHONG, THEERANAN; PIROONPAN, THANANCHAI; THIPE, VELAPHI C.; KHOOBCHANDANI, MENKA; KATTI, KAVITA; KATTI, KATTESH V.; PASANPHAN, WANVIMOL. Water-soluble chitosan conjugated DOTA-bombesin peptide capped gold nanoparticles as a targeted therapeutic agent for prostate cancer. Nanotechnology, Science and Applications, v. 14, p. 69-89, 2021. DOI: 10.2147/NSA.S301942. Disponível em: http://repositorio.ipen.br/handle/123456789/32047. Acesso em: $DATA.

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Abstract: Fungal bioburdens in filters from car air conditioning systems represent a potential risk of respiratory or pulmonary diseases to both passengers and drivers. The present study demonstrated high fungal contamination in air conditioning filters collected from fifty-seven vehicles from the city of São Paulo, Brazil. The filters samples were irradiated with 10, 15 and 20 kGy gamma ray doses with a cobalt-60 source. The presence of Aspergillus flavus, Penicillium glabrum and Fusarium incarnatum-equiseti remaining after the ionizing treatment with 10 and 15 kGy. The radioresistant pathogenic species was confirmed through genetic sequencing of the ITS, β-tubulin and calmodulin gene rDNA regions. The 20 kGy dose was efficient in inhibiting pathogenic fungi growth in all samples but promoted the fungal decontamination in 79% of the samples. These results and other efforts will enable ionizing radiation to become an important tool in contributing to the recycling of automotive vehicle air filters and in ensuring indoor air quality for both drivers and passengers.

Palavras-Chave: ionizing radiations; air quality; indoor air pollution; vehicles; air conditioning; fungal diseases; air filters; air cleaning systems

AQUINO, SIMONE; LIMA, JOSE E.A. de; REIS, TATIANA A. dos; CORREA, BENEDITO; BORRELY, SUELI I. Mycoflora and DNA sequencing analysis of radioresistant fungi isolated from irradiated vehicular air conditioning filters collected in São Paulo, Brazil. Microbiology Research International, v. 9, n. 1, p. 1-15, 2021. DOI: 10.30918/MRI.91.21.011. Disponível em: http://repositorio.ipen.br/handle/123456789/32045. Acesso em: $DATA.

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Abstract: In this study scaffolds of nanohydroxyapatite (nHA) and anionic collagen (C) combined with plant extracts intended for bone tissue repair were developed. Grape seed (P), pomegranate peel (R) and jabuticaba peel (J) extracts were used as collagen crosslinker agents in order to improve the materials properties. All crude extracts were effective against Staphylococcus aureus, but only for CR scaffold inhibition zone was noticed. The extracts acted as crosslinking agents, increasing enzymatic resistance and thermal stability of collagen. The extracts showed cytotoxicity at the concentrations tested, while nHA increased cell viability. The scaffolds presented porosity and pore size appropriate for bone growth. CR, CnHAP, CnHAR and CnHAJ increased the cell viability after 24 h. The combination of collagen, nHA and plant extracts offers a promising strategy to design novel biomaterials for bone tissue regeneration.

Palavras-Chave: bone tissues; collagen; regeneration; flavonoids

GARCIA, CLAUDIO F.; MARANGON, CRISIANE A.; MASSIMINO, LIVIA C.; KLINGBEIL, MARIA F.G.; MARTINS, VIRGINIA C.A.; PLEPIS, ANA M. de G. Development of collagen/nanohydroxyapatite scaffolds containing plant extract intended for bone regeneration. Materials Science & Engineering C, v. 123, p. 1-12, 2021. DOI: 10.1016/j.msec.2021.111955. Disponível em: http://repositorio.ipen.br/handle/123456789/32043. Acesso em: $DATA.

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Abstract: In this study, the microstructure and corrosion resistance of the stir zone (SZ) of the AA2198-T8 Al-Cu-Li alloy welded by friction stir welding (FSW) were investigated by microscopy, immersion tests and electrochemical techniques such as measurements of open circuit potential variation with time, and scanning vibrating electrode technique (SVET) measurements. A low chloride-containing solution (0.005 mol L−1 NaCl) was employed in the corrosion studies and severe localized corrosion (SLC) was observed in the SZ related to intergranular attack. The results were compared to those of the non-affected areas by FSW, also known as base metal (BM). In the BM, SLC was found and the type of attack related to it was intragranular. In both zones, BM and SZ, SLC was due to precipitates of high electrochemical activity, specifically T1 (Al2CuLi) phase in the BM, whereas TB (Al7Cu4Li) / T2 (Al6CuLi3) in the SZ. Scanning vibrating electrode technique (SVET) analysis was very useful in the study of SLC in the AA2198-T8 alloy showing the development of high anodic current densities at the mouth of the SLC sites.

Palavras-Chave: electrochemistry; friction welding; stir reactor; corrosion resistance; microstructure

MACHADO, CARULINE de S.C.; DONATUS, UYIME; MILAGRE, MARIANA X.; ARAUJO, JOAO V. de S.; VIVEIROS, BARBARA V.G. de; KLUMPP, RAFAEL E.; PEREIRA, VICTOR F.; COSTA, ISOLDA. How microstructure affects localized corrosion resistance of stir zone of the AA2198-T8 alloy after friction stir welding. Materials Characterization, v. 174, p. 1-14, 2021. DOI: 10.1016/j.matchar.2021.111025. Disponível em: http://repositorio.ipen.br/handle/123456789/32041. Acesso em: $DATA.

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Abstract: Thermoplastic elastomers (TPEs), based in PP (Polypropylene) / EPDM (Ethylene Propylene Diene Monomer) have as purpose improving PP resistance and impact, aiming to a more comprehensive use in automotive market, among edifications, construction and packaging sectors, due to their recyclability properties. PP is a commodity, with a high melting point, high mechanical resistance and low density, posing a balance between physical and mechanical properties; in addition, it shows an easy processing, at low cost. In order to minimize this deficiency, EPDM, an impact modifier, can be used. Nevertheless, most of polymeric blends are incompatible and immiscible, i.e., show a mutual and limited solubility and in most of cases, a high interfacial tension. However, there is a relatively low interfacial tension (force which acts on transformation of a continuous structure in a dispersion) between PP and EPDM (approximately 0.3 mN.m-1), reducing the rate of breakup and facilitating the build-up of a continuous structure. This work aims to the study of compatibility of PP and EPDM blends and variation of mechanical properties, emphasizing that many properties of thermoplastic elastomers can be processed according with conventional thermoplastics methods: herein, PP/EPDM blends, 90/10, 80/20, 70/30 and 50/50 were characterized according to: Mechanical essays, Differential Scanning Calorimetry, Thermogravimetric Analyses, Melt Flow Index, Izod Impact Strength and Dynamic mechanical Analyses.

Palavras-Chave: thermoplastics; elastomers; thermal gravimetric analysis; polymers; compatibility

SCAGLIUSI, SANDRA R.; CARVALHO, ELIZABETH C.L.; LUGAO, ADEMAR B. Introduction to the study of mechanical properties of terpolymer PP/EPDM mixtures. Journal of Research Updates in Polymer Science, v. 10, p. 1-8, 2021. DOI: 10.6000/1929-5995.2021.10.1. Disponível em: http://repositorio.ipen.br/handle/123456789/32039. Acesso em: $DATA.

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Abstract: With the popularization of 3D printing technologies, it is now possible to develop patient specific simulators and various other accessories using this technology in medical physics and dosimetry. This work aims to evaluate the electronic equilibrium of 3D printed phantoms using PLA and ABS filaments compared to PMMA for 137Cs gamma rays using OSL dosimetry. A Landauer microStar ii commercial OSL system was commissioned and it was used nanoDot dosimeters. Phantom plates with 2.5, 3.0 and 5.0 mm thickness were used to obtain electronic equilibrium for 137Cs gamma rays. Measurements were compared with PMMA measurements at standard conditions. Results show that measurements with ABS and PLA thicknesses of 2.5 and 3.0 mm presents dosimetry results within irradiation uncertainty. More accuracy is obtained using 3.0 mm for both PLA and ABS phantoms, with differences in less than 0.5%. It can be concluded that PLA and ABS 3D phantom plates has similar properties of PMMA for 137Cs gamma rays dosimetry and can be used for developing dosimetry accessories for this energy photon beam.

Palavras-Chave: phantoms; 3d printing; gamma radiation; photoluminescence; dosimetry

VILLANI, D.; RODRIGUES JUNIOR, O.; MASCARENHAS, Y.M.; CAMPOS, L.L. Study on electronic equilibrium of 137Cs gamma radiation for 3D printed phantoms using OSL dosimetry. Journal of Physics: Conference Series, v. 1826, p. 1-6, 2021. DOI: 10.1088/1742-6596/1826/1/012057. Disponível em: http://repositorio.ipen.br/handle/123456789/32037. Acesso em: $DATA.

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Abstract: The OSL and the TL techniques are used in several fields of radiation dosimetry. The dosimeters are affected by a signal loss in the time between the irradiation and readout (fading). This undesirable characteristic can cause an underestimation of the irradiation dose. The fading estimation of SOL-GEL α-Al2O3 with several different concentrations of impurities is reported. The thermal fading and the light-induced fading of the SOL-GEL α-Al2O3 detectors were estimated. Furthermore, the exponential equations used to interpolate the experimental results were presented.

Palavras-Chave: photoluminescence; sol-gel process; aluminium oxides; dosimetry

POLO, I.O.; CALDAS, L.V.E. Fading estimation of SOL-GEL α-Al2O3 detectors. Journal of Physics: Conference Series, v. 1826, p. 1-6, 2021. DOI: 10.1088/1742-6596/1826/1/012045. Disponível em: http://repositorio.ipen.br/handle/123456789/32035. Acesso em: $DATA.

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Abstract: There is a serious, and growing concern about the increased risk of the emergence of a secondary cancer, radio-induced, associated with radiotherapy treatments. To assess the radiation doses to organs outside the target volume, in this work, several computational exposure scenarios were modelled, based on Monte Carlo simulation (MCNPX code). A Varian 2100c accelerator, and a female virtual anthropomorphic phantom were used, in a simulated treatment of cervical cancer. The determination of the dispersed dose would be important for assessing the risk in different organs or tissues. Four treatment fields were applied, varying the gantry angle. It was possible to observe that the conversion factors for equivalent dose were higher for the AP projection. For the RLAT and LLAT projections, the results were similar, fact that may be attributed to the symmetrical distributions of the organs in relation to the radiation source. The results presented in this work showed that the computational exposure scenario provides a versatile and accurate tool to estimate in a ready way the absorbed doses during a cervical treatment.

Palavras-Chave: absorbed radiation doses; animal tissues; computerized simulation; dosimetry; monte carlo method; organs; phantoms; radiotherapy; uterus

SANTOS, WILLIAM S.; NEVES, LUCIO P.; PERINI, ANA P.; SANTOS, CARLA J.; BELINATO, WALMIR; SILVA, ROGERIO M.V.; SOARES, MARIA R.; VALERIANO, CAIO C.; CALDAS, LINDA V.E. Computational modelling of cervix radiation procedure using a virtual anthropomorphic phantom and the MCNPX code. Journal of Physics: Conference Series, v. 1826, p. 1-8, 2021. DOI: 10.1088/1742-6596/1826/1/012040. Disponível em: http://repositorio.ipen.br/handle/123456789/32033. Acesso em: $DATA.

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Abstract: 3D printing techniques and materials have become widely available in the last couple of decades and remains a hot topic of study as new materials can lead to new applications. This study aims to evaluate the attenuation behaviour of GMASS over photon beams ranging from 29.7 up to 661.7keV, comparing with pure ABS and using theoretical data of pure lead as reference. It was used the transmission method to obtain experimental attenuation coefficients to all materials and theoretical data. HVL and TVL calculations were also performed. Results show that ABS+W has higher attenuation than ABS+Bi and pure ABS. Using the lead theoretical reference data it can be concluded that although ABS+Bi and ABS+W attenuates less than pure lead, the 3D printing filaments can be used to create shielding tolls depending on radiation energy and application.

Palavras-Chave: attenuation; cesium 137; dosimetry; energy dependence; filaments; photon beams; polymers; radiations; shielding

VILLANI, D.; SAVI, M.; ANDRADE, M.A.B.; CAMPOS, L.L.; POTIENS, M.P.A. Characterization of ABS + W and ABS + Bi 3D printing filaments attenuation for different photon beams. Journal of Physics: Conference Series, v. 1826, p. 1-8, 2021. DOI: 10.1088/1742-6596/1826/1/012037. Disponível em: http://repositorio.ipen.br/handle/123456789/32031. Acesso em: $DATA.

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Abstract: It was investigated in order to better understand the relationship between the low presence of Mg in the Ti–Nb–Sn alloy in its mechanical and microstructural properties by the powder metallurgy technique for biomedical application. The blended powders with the nominal composition of Ti–34Nb–6Sn were obtained by milling at 200 rpm/40 min, compacted at 200 MPa. The sintering were carried out at 900 °C/2 h and at 1110 °C/2 h, followed by furnace cooling. The particle size was characterized by the dynamic image analyzer (DIA). The phases quantification and their microstructure were characterized by an X-ray diffractometer (XRD) and a scanning electron microscope (SEM). The porosity was characterized by the Archimedes method and also bi-dimensionally by the Image J software. The mechanical tests were performed by the impulse excitation (Sonelastic ®) technique, in order to evaluate the elastic modulus (E) of the sintered materials and the hardness and resistance by the Rockwell method. The results indicated that the sintering at 1100 °C in the materials with Mg, still had particles of Nb not diffused. The microstructure was basically formed by two phases with the presence of Nb non-diffused in all conditions except at 1100 °C in the system without Mg. The β phase % for systems without and with Mg at 900 °C was approximately 80% and 65%. At 1100 °C, 76% and 78%. The E and hardness were 31 GPa and 226 MPa at 900 °C; 49 GPa and 344 MPa at 1100 °C for materials with Mg. The O and N content increased approximately 1.3 times when adding Mg powder.

Palavras-Chave: titanium alloys; magnesium; young modulus; elasticity; powder metallurgy; medical supplies

ROSSI, MARIANA C.; BAYERLEIN, DANIEL L.; GOUVEA, EBER de S.; RODRIGUEZ, MONTSERRAT V.H.; ESCUDER, ANGEL V.; BORRAS, VICENTE A. Evaluation of the influence of low Mg content on the mechanical and microstructural properties of β titanium alloy. Journal of Materials Research and Technology, v. 10, p. 916-925, 2021. DOI: 10.1016/j.jmrt.2020.12.103. Disponível em: http://repositorio.ipen.br/handle/123456789/32029. Acesso em: $DATA.

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Abstract: In most of the machining processes, the application of surface texturing is one of the most remarkable and promising research fronts in relation to the use of tribological concepts for improving machinability. This paper aims to review the most recent articles on this theme (from 2016 to date) to assist the researchers in the state of the art of this technology, guide the forthcoming related investigations, and thus, fill the identified research gaps. The texture effect in machining was comprehensively reviewed considering chip formation, cutting forces, cutting temperature, lubrication, surface integrity, and tool life. The present review highlights and summarizes the major findings with emphasis on the influencing parameters, such as workpiece and tool material, cutting process, lubri-cooling condition, texture geometry, and texture manufacturing technique. The overwhelming majority of the studies presented tool surface textures manufactured by laser ablation on the rake face of uncoated WC-Co tools. In this relation, turning was identified as mostly used machining process and dry condition as the chiefly implemented lubri-cooling environment. Moreover, most of the textures were noticed with linear grooves and dimple geometries, whereas the work materials mostly investigated were the hardened/high alloy steels and titanium alloys.

Palavras-Chave: machining; surfaces; texture; cutting tools

MACHADO, ALISSON R.; SILVA, LEONARDO R.R. da; SOUZA, FELIPE C.R. de; DAVIS, RAHUL; PEREIRA, LEANDRO C.; SALES, WISLEY F.; ROSSI, WAGNER de; EZUGWU, EMMANUEL O. State of the art of tool texturing in machining. Journal of Materials Processing Technology, v. 293, p. 1-23, 2021. DOI: 10.1016/j.jmatprotec.2021.117096. Disponível em: http://repositorio.ipen.br/handle/123456789/32027. Acesso em: $DATA.

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Abstract: Development of new near infrared luminescent (NIR) emitters improves our understanding of their fundamental structure–property relationships. The ability to use efficient energy transfer to convert ultraviolet or visible light photons to enhance the NIR emission has attracted a great deal of attention in down-conversion applications. Taking advantage of the sol–gel impregnation process and growth of materials along a support or template, core–shell structured nanofibers of ZnAl2O4 – based ceramic doped with cerium and neodymium were synthesized with the help of an elaborate facile and cost-efficient strategy. The color-tunable emissions make this material a suitable host for a wide range of applications, e.g., bio-imaging, security markers, imaging devices, optical coatings, and solar cells. This research correlates the defects and the remarkable optical properties of the developed structures. Specified conditions of sol–gel processing combined with the incorporation of rare-earth elements in various concentrations provide the possibility of tuning the ratio between Ce3+ and Ce4+ in the nanofibers with an average diameter of 50 nm and, therefore, their functional response. It is important to clarify the role of trivalent and tetravalent cerium cations in the modulation of NIR emission to establish the luminescence mechanism. The NIR emitter luminescent compound ZnAl2O4:Nd,Ce, which adopts a spinel-type structure, is studied using the X-ray absorption near-edge structure technique. For the first time, this study reveals the energy transfer from Ce3+ to Nd3+ and the enhancement of the NIR emission due to the presence of Ce4+ in the ZnAl2O4:Nd,Ce spinel compound. Cytotoxicity analyses suggest the viability of the synthesized nanofibers, which opens new avenues in bio-imaging applications.

Palavras-Chave: nanofibers; near infrared radiation; zinc; cerium; neodymium

ROJAS-HERNANDEZ, ROCIO E.; RUBIO-MARCOS, FERNANDO; GORNI, GIULIO; MARINI, CARLO; DANILSON, MATI; PASCUAL, LAURA; ICHIKAWA, RODRIGO U.; HUSSAINOVA, IRINA; FERNANDEZ, JOSE F. Enhancing NIR emission in ZnAl2O4:Nd,Ce nanofibers by co-doping with Ce and Nd: a promising biomarker material with low cytotoxicity. Journal of Materials Chemistry C, v. 9, n. 2, p. 657-670, 2021. DOI: 10.1039/d0tc04752j. Disponível em: http://repositorio.ipen.br/handle/123456789/32025. Acesso em: $DATA.

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Abstract: Objective: To evaluate the efficacy of Nd:YAG laser associated with calcium-phosphate desensitizing pastes on dentin permeability and tubule occlusion after erosive/abrasive challenges. Methodology: Dentin specimens were exposed to 17% ethylene diamine tetra-acetic acid (EDTA) solution for 5 min and randomly allocated into five groups: G1, control (no treatment); G2, Nd:YAG laser (1 W, 10 Hz, 100 mJ, 85 J/cm2); G3, Laser + TeethmateTM Desensitizer; G4, Laser + Desensibilize Nano P; and G5, Laser+Nupro®. Specimens underwent a 5-day erosion-abrasion cycling. Hydraulic conductance was measured post-EDTA, post-treatment, and post-cycling. Post-treatment and post-cycling permeability (%Lp) was calculated based on post-EDTA measurements, considered 100%. Open dentin tubules (ODT) were calculated at the abovementioned experimental moments using scanning electron microscopy and ImageJ software (n=10). Data were analyzed using two-way repeated measures ANOVA and Tukey’s test (α=0.05). Results: G1 presented the highest %Lp post-treatment of all groups (p<0.05), without significantly differences among them. At post-cycling, %Lp significantly decreased in G1, showed no significant differences from post-treatment in G3 and G4, and increased in G2 and G5, without significant differences from G1 (p>0.05). We found no significant differences in ODT among groups (p>0.05) post-EDTA. At post-treatment, treated groups did not differ from each other, but presented lower ODT than G1 (p<0.001). As for post-cycling, we verified no differences among groups (p>0.05), although ODT was significantly lower for all groups when compared to post-EDTA values (p<0.001). Conclusion: All treatments effectively reduced dentin permeability and promoted tubule occlusion after application. Combining Nd:YAG laser with calcium-phosphate pastes did not improve the laser effect. After erosive-abrasive challenges, treatments presented no differences when compared to the control.

Palavras-Chave: dentistry; neodymium lasers; calcium phosphates; sensitivity analysis; permeability

MAXIMIANO, VINICIUS; MACHADO, ALANA C.; LOPES, RAQUEL M.; RABELO, FERNANDA E.M.; GAROFALO, STEPHANIE A.; ZEZELL, DENISE M.; ARANHA, ANA C.C.; SCARAMUCCI, TAIS. Association of Nd:YAG laser and calcium-phosphate desensitizing pastes on dentin permeability and tubule occlusion. Journal of Applied Oral Science, v. 29, p. 1-11, 2021. DOI: 10.1590/1678-7757-2020-0736. Disponível em: http://repositorio.ipen.br/handle/123456789/32021. Acesso em: $DATA.

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Abstract: The advancement of direct ethanol fuel cell (DEFC) represents a real challenge to electrochemical science because ethanol changes significantly the triple phase boundary properties such as the redox reactions and the proton transport. Ethanol molecules promote poor fuel cell performance due to their slow oxidation rate, reduction of the proton transport due to high affinity of ethanol by the membrane, and due to mixed potential when the ethanol molecules reach the cathode by crossover. DEFC performance has been improved by advances in the membranes, e.g., low ethanol crossover polymer composites, or electrode materials, e.g., binary/ternary catalysts. Herein, high temperature (130 °C) DEFC tests were systematically investigated by using optimized electrode and electrolyte materials: Nafion-SiO2 hybrid electrolyte and well-alloyed PtSn/C electrocatalyst. By optimizing both the electrode and the electrolyte in conjunction, DEFCs operating at 130 °C exhibited a threefold increase on performance as compared to standard commercially available materials.

Palavras-Chave: direct ethanol fuel cells; electrocatalysts; hybridization; electrolytes; nanocomposites

DRESCH, MAURO A.; MATOS, BRUNO R.; GODOI, DENIS R.M.; LINARDI, MARCELO; FONSECA, FABIO C.; VILLULLAS, HEBE de las M.; SANTIAGO, ELISABETE I. Advancing direct ethanol fuel cell operation at intermediate temperature by combining Nafion-hybrid electrolyte and well-alloyed PtSn/C electrocatalyst. International Journal of Hydrogen Energy, v. 46, n. 24, p. 13252-13264, 2021. DOI: 10.1016/j.ijhydene.2021.01.123. Disponível em: http://repositorio.ipen.br/handle/123456789/32019. Acesso em: $DATA.

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Abstract: Thermochromic nanofibers (NFs) have emerged as an important class of nanostructured materials and have found a broad range of technologic applications. Herein, an optical fiber temperature sensor composed of coating electrospun thermochromic NFs on the end-face of fiber is reported. A composite coating consisting of an aqueous dispersion of a thermochromic material (cobalt-doped zinc phosphate or also called cobalt-doped hopeite -CoHo), in polyglycerol dendrimer (PGD), was directly electrospun onto the end-face surface of multimode optical fiber for the fabrication of temperature optical fiber sensor. Morphological features and optical properties of the resulting electrospun CoHo:PGD NFs were assessed. The diameter of the electrospun CoHo:PGDNFs deposited on the end-face of optical fiber was 500 ± 14 nm. The spectroscopic absorption of the electrospun CoHo:PGDNFs at 630 nm is measured to determine their relationship with temperature. The results under variable temperature from 25 to 250 °C indicate good linearity and show the potential of using CoHo:PGDNFs sensing applications for control in industrial processes that require a steady or changing temperature. To extract the chromaticity profile of the CoHo:PGDNFs and their temperature dependence, a multilayer feed-forward artificial neural network (ANN) was used. ANN has been successfully employed to extract temperature information from the chromatic changes of CoHo:PGDNFs.

Palavras-Chave: electrodes; nanofibers; sensors; optical properties

PERES, MAYARA L. de O.; NETO, ESTACIO T.W.; QUEIROZ, ALFREDO A.A.E. de; QUEIROZ, ALVARO A.A. de. Intelligent electrospun thermochromic composite nanofibers for temperature measurements. IEEE Sensors Letters, v. 5, n. 3, 2021. DOI: 10.1109/LSENS.2021.3058056. Disponível em: http://repositorio.ipen.br/handle/123456789/32017. Acesso em: $DATA.

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Abstract: Aminoacetone (1-aminopropan-2-one), a putative minor biological source of methylglyoxal, reacts like other α-aminoketones such as 6-aminolevulinic acid (first heme precursor) and 1,4-diaminobutanone (a microbicide) yielding electrophilic α-oxoaldehydes, ammonium ion and reactive oxygen species by metal- and hemeprotein-catalyzed aerobic oxidation. A plethora of recent reports implicates triose phosphate-generated methylglyoxal in protein crosslinking and DNA addition, leading to age-related disorders, including diabetes. Importantly, methylglyoxal-treated hemoglobin adds four water-exposed arginine residues, which may compromise its physiological role and potentially serve as biomarkers for diabetes. This paper reports on the co-oxidation of aminoacetone and oxyhemoglobin in normally aerated phosphate buffer, leading to structural changes in hemoglobin, which can be attributed to the addition of aminoacetone-produced methylglyoxal to the protein. Hydroxyl radical-promoted chemical damage to hemoglobin may also occur in parallel, which is suggested by EPR-spin trapping studies with 5,5-dimethyl-1-pyrroline-N-oxide and ethanol. Concomitantly, oxyhemoglobin is oxidized to methemoglobin, as indicated by characteristic CD spectral changes in the Soret and visible regions. Overall, these findings may contribute to elucidate the molecular mechanisms underlying human diseases associated with hemoglobin dysfunctions and with aminoacetone in metabolic alterations related to excess glycine and threonine.

Palavras-Chave: hemoglobin; electron transfer; amino acids; acetone; glyoxal; peroxy radicals

RAMOS, LUIZ D.; MANTOVANI, MARIANA C.; SARTORI, ADRIANO; DUTRA, FERNANDO; STEVANI, CASSIUS V.; BECHARA, ETELVINO J.H. Aerobic co-oxidation of hemoglobin and aminoacetone, a putative source of methylglyoxal. Free Radical Biology and Medicine, v. 166, p. 178-186, 2021. DOI: 10.1016/j.freeradbiomed.2021.02.023. Disponível em: http://repositorio.ipen.br/handle/123456789/32015. Acesso em: $DATA.

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Abstract: The contaminants of emerging concern (CECs) have been receiving global attention due to their worldwide presence in water bodies. The CECs could be originated from synthetic or natural sources, and they are not commonly monitored, although these substances are continuously reaching the aquatic environment. The main goal of this study was to determine the occurrence of some target CECs in São Paulo state surface water, once there is practically no information on the presence and concentration range of these substances at the studied sites. In addition, the present study aimed to assess adverse effects in the non-target fish embryo of Danio rerio (zebrafish) after exposure to surface water organic extract samples during 96 h using FET test. The CECs in surface water samples were determined by solid-phase extraction and liquid chromatography coupled by mass spectrometry. A 2-year study was assessed in 7 rivers and 3 reservoirs at São Paulo state, where 25 of the 30 analyzed substances were quantified, being caffeine the substance with the highest concentration range (5.5 ng L−1 to 69 μg L−1) and detected in 95% of analyzed samples, followed by bisphenol A (6.5–1300 ng L−1) and carbendazim (4.7–285 ng L−1), found in 50% and 85% of the analyzed samples, respectively. The chemical analysis and biological test were not performed in order to show a direct relationship between concentrations and observed effects on embryos; however, the combined approach can provide a better understanding of the adverse effects caused by mixtures of substances at relevant environmental concentrations. Regarding the adverse effects, it was observed that in the samples from sites with higher anthropogenic activity in the surroundings, there was also a higher mortality rate in organisms. At the Ribeirão Pires River and Sapucaí-Guaçu River, the mortality rate during the 2-year study was 21.6% and 9.3%, respectively. The morphological abnormality rates were higher at Ribeirão Grande (21.4%) and Ribeirão Pires (29.5%) Rivers. The obtained results aim to show that even in low concentrations (ng–μg L−1) the CECs can cause adverse effects on non-target species, and because of that, new chemical indicators would be important to monitor the water quality and protect the aquatic biota.

Palavras-Chave: surface waters; embryos; fishes; acute exposure; toxicity; environment

MARTINI, GISELA de A.; MONTAGNER, CASSIANA C.; VIVEIROS, WILLIAM; QUINAGLIA, GILSON A.; FRANCA, DANIELA D.; MUNIN, NIVEA C.G.; LOPES-FERREIRA, MONICA; ROGERO, SIZUE O.; ROGERO, JOSE R. Emerging contaminant occurrence and toxic effects on zebrafish embryos to assess the adverse effects caused by mixtures of substances in the environment. Environmental Science and Pollution Research, v. 28, n. 16, p. 20313-20329, 2021. DOI: 10.1007/s11356-020-11963-x. Disponível em: http://repositorio.ipen.br/handle/123456789/32013. Acesso em: $DATA.

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Abstract: Pd−In/C electrocatalysts were synthesized by the adapted borohydride reduction method in different atomic ratios. Electrocatalysts were evaluated by conventional electrochemical techniques and direct glycerol fuel cells. X-ray diffraction profiles indicated the structure of Pd and In (fcc) phases, as well as the presence of In higher oxidation states. Regarding Transmission electron microscopy, it showed the particle‘s average diameters between 6.1–12.7 nm. All PdIn/C electrocatalysts showed high current values for −0.30 V vs. Ag/AgCl, which the best one was PdIn/C 90 : 10. Higher performance for glycerol oxidation was observed in polarization curves at 90 °C for PdIn/C (30 : 70) composition.

Palavras-Chave: borohydrides; glycerol; alkaline electrolyte fuel cells; fuel cells; oxidation; polarization

NANDENHA, JULIO; RAMOS, CARLOS E.D.; SILVA, SIRLANE G. da; SOUZA, RODRIGO F.B. de; FONTES, ERIC H.; OTTONI, CRISTIANE A.; OLIVEIRA NETO, ALMIR. Borohydride reduction method for PdIn/C electrocatalysts synthesis towards glycerol electrooxidation under alkaline condition. Electroanalysis, v. 33, n. 4, p. 1115-1120, 2021. DOI: 10.1002/elan.202060322. Disponível em: http://repositorio.ipen.br/handle/123456789/32011. Acesso em: $DATA.

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Abstract: The influence of hot-stamping process on the corrosion properties of Al-Si coating on 22MnB5 steel was locally evaluated using a depth profiling approach combining GDOES and electrochemical micro cell. The results highlight the complexity of the system and the high dependence of the local galvanic series on the hot-stamping process. Due to iron diffusion from the steel substrate into the coating, the Al-rich layers presented active behaviour, whereas the initial coating condition showed a passive behaviour. Conversely, Fe/Si-rich sublayers acted as protective barrier for the steel substrate, as they show passive behaviour with nobler corrosion potentials and lower current densities.

Palavras-Chave: corrosion; coatings; aluminium compounds; aluminium silicides; steels; hardening

COUTO, CAMILA P.; ANDREATTA, FRANCESCO; LANZUTTI, ALEX; COSTA, ISOLDA; PANOSSIAN, ZEHBOUR; DE GRAEVE, IRIS; TERRYN, HERMAN; ROSSI, JESUALDO L.; REVILLA, REYNIER I. Depth profiling approach to evaluate the influence of hot stamping on the local electrochemical behaviour and galvanic series of hot-dip Al-Si coating on 22MnB5 steel. Corrosion Science, v. 185, p. 1-12, 2021. DOI: 10.1016/j.corsci.2021.109435. Disponível em: http://repositorio.ipen.br/handle/123456789/32009. Acesso em: $DATA.

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Abstract: Designing efficient anode CO-tolerant electrocatalysts is critical in low-temperature fuel cell catalysts fueled either by H2/CO or alcohol. We demonstrate that the incorporation of TiO2 nanocubes (TiO2NCs) on Carbon Vulcan supports, followed by the synthesis of Pt NPs at their surface (Pt/TiO2NCs-C material), led to improvements in performance towards the electrooxidation of carbon monoxide, ethanol, methanol, ethylene glycol, and glycerol in acidic media relative to the commercial Pt/C and Pt/TiO2-C counterparts employing commercial TiO2. The nanocubes enabled changes in the electronic properties of Pt NPs while contributing to the bifunctional mechanism as compared to Pt/C and Pt/TiO2-C with commercial TiO2. Fuel cell experiments fed with H2/CO steam showed that Pt/TiO2NCs-C employing nanocubes was resistant to CO-poisoning, yielding superior performance in operational conditions. The results reported herein have important implications for developing electrocatalysts with superior performances in PEMFCs.

Palavras-Chave: electrolysis; catalysts; titanium oxides; carbon

ANTONIASSI, RODOLFO M.; QUIROZ, JHON; BARBOSA, EDUARDO C.M.; PARREIRA, LUANNA S.; ISIDORO, ROBERTA A.; SPINACE, ESTEVAM V.; SILVA, JULIO C.M.; CAMARGO, PEDRO H.C. Improving the electrocatalytic activities and CO tolerance of Pt NPs by incorporating TiO2 nanocubes onto carbon supports. ChemCatChem, v. 13, n. 8, p. 1931-1939, 2021. DOI: 10.1002/cctc.202002066. Disponível em: http://repositorio.ipen.br/handle/123456789/32007. Acesso em: $DATA.

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Abstract: Os impactos das atividades antrópicas sobre os ecossistemas terrestres com efeitos dos desmatamentos, exploração madeireira, queimadas, impermeabilização do solo, contaminação de mananciais, entre outros, causam mudanças ambientais que afetam negativamente o planeta e os seres vivos. Estas mudanças incluem a perda da capacidade produtiva dos ecossistemas, problemas atmosféricos e contribuição ao efeito estufa. O reúso da água de chuva entra nesse cenário para ajudar na manutenção e conservação da água. Através da construção de sistemas hidráulicos para captação da chuva e a conscientização da população com este problema é possível minimizar os efeitos da escassez de água no planeta. Com isso visou-se expor neste trabalho o cenário das condições hídricas atuais do Brasil e a utilização do reúso da água de chuva como alternativa sustentável para os períodos de escassez.

Palavras-Chave: rain water; recycling; water supply; sustainability; sustainable development; water resources

MOREIRA, TATIANA M.; SEO, EMILIA S.M. Reúso da água de chuva: uma alternativa sustentável para os períodos de escassez hídrica. Brazilian Journal of Animal and Environmental Research, v. 4, n. 1, p. 671-683, 2021. DOI: 10.34188/bjaerv4n1-056. Disponível em: http://repositorio.ipen.br/handle/123456789/32005. Acesso em: $DATA.

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Abstract: Elemental and isotopic composition of tunnel dusts collected from Jânio Quadros (JQ) and Maria Maluf (MM) tunnels in São Paulo city were analyzed aiming to determine the potential sources of trace elements in these environments. Sampling was performed in the summer and winter of 2017. Elemental mass fractions were determined by Instrumental Neutron Activation Analysis (INAA) and Graphite Furnace Electrothermal Atomic Absorption Spectrometry (GF-AAS) for 28 elements. Isotopic signatures of Pb and Zn were determined by Thermal Ionization Mass Spectrometry (TIMS) and Multicollector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS), respectively. The mean mass fractions of elements, such as Pb, Cd, Zn, Sb and Cu, were in general similar to the reported in the literature, in studies that demonstrated urban contamination by potentially toxic elements. Statistics demonstrated significant differences in mass fractions between the tunnels for most analyzed elements. Results showed that rare earth elements, U and Th, mostly associated with geogenic sources, presented higher concentrations in MM tunnels, while elements frequently related to vehicular emissions (Sb, Zn, Ba, Cu and Pb) presented mean mass fraction values higher in JQ tunnel, pointing to a more important contamination in JQ tunnel. No significant differences in the mass fractions between campaigns were observed, evidencing that tunnels are not much affected by external weather conditions. Pb isotopic analysis presented 206Pb/207Pb ratios between 1.1715 and 1.1791 and 208Pb/206Pb ratios between 2.0889 and 2.0961, which pointed out to a vehicular signature, related to tailpipe emissions. On the other hand, Zn isotope data also suggested a vehicular signature, but mostly related to the wear of tires and brakes. Grain size distribution analysis showed that the smallest fractions of dust contained, on average, about 10% of particulate matter of aerodynamic diameter smaller than 10 μm, fractions highly inhalable, what may be a concern to human health. Enrichment factors (EFs) showed that Cr, Zn, Cu, Cd, Pb and Sb are the most enriched elements, in both tunnels, but higher EFs were found for JQ tunnel. Principal Component Analysis revealed a profile for a crustal source, marked by U, Th and rare earth elements, whereas vehicular sources were characterized mostly by Pb, Ti and V from gasoline/diesel combustion; Pb and Ti from road paints; Sb, Ba and Zn from brakes, and Zn from wear of steel and tires. These results indicate an important anthropic impact in the tunnels and that vehicular traffic is the main source of potentially toxic elements.

Palavras-Chave: absorption spectroscopy; contamination; dusts; elements; icp mass spectroscopy; isotope ratio; neutron activation analysis; toxic materials; tunnels; urban areas; x-ray diffraction; x-ray fluorescence analysis

NORY, RENATA M.; FIGUEIREDO, ANA M.G.; SOUTO-OLIVEIRA, CARLOS E.; BABINSKI, MARLY. Urban contamination sources in tunnel dusts from São Paulo city: elemental and isotopic characterization. Atmospheric Environment, v. 254, p. 1-14, 2021. DOI: 10.1016/j.atmosenv.2021.118188. Disponível em: http://repositorio.ipen.br/handle/123456789/32003. Acesso em: $DATA.

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Abstract: In radiation physics, the study of new alternative dosimeters is of interest to the growing branch of dosimetric characterization for radiotherapy applications. The goal of this work was to expose bone samples to high doses and evaluate their linearity response to gamma rays. The Fourier Transform Infrared (FTIR) spectrophotometry technique was employed as the evaluation technique, and based on the spectrophotometry absorbance profiles the linearity was assessed based on the following methods: Area Under the Curve (AUC), Wavenumber Method (WM), Partial Component Regression (PCR) and Partial Least-Square Regression (PLSR) methods. The bone samples were irradiated with absorbed doses of 10 Gy up to 500 Gy using a 60Co Gamma Cell-220 system. The results showed, for the calibration curves of the system, adequate linearity on all methods. In conclusion, the results indicate a good linear response and therefore an interesting potential radiation detector.

Palavras-Chave: gamma radiation; radiation detectors; irradiation; dosimetry; fourier transformation; infrared spectra; radiation doses

OLIVEIRA, LUCAS N. de; NASCIMENTO, ERIBERTO O. do; MORAIS JUNIOR, PEDRO de A.; ANTONIO, PATRICIA de L.; CALDAS, LINDA V.E. Evaluation of high-linearity bone radiation detectors exposed to gamma-rays via FTIR measurements. Applied Radiation and Isotopes, v. 170, p. 1-6, 2021. DOI: 10.1016/j.apradiso.2021.109598. Disponível em: http://repositorio.ipen.br/handle/123456789/32001. Acesso em: $DATA.

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Abstract: In the presented manuscript, spherical silver nanoparticles (AgNPs) which were prepared via green chemical method in a single step take only a few minutes to be ready as a Hg2+ ions detector based on the plasmon band changes. The AgNPs were obtained with the aqueous extract of Mimusops coriacea leaves. The components of the extract as tannins and polyphenolic compounds were responsible for the reduction in metal ions and the particles encapsulation. The AgNPs were characterized by UV–Vis spectroscopy, fluorescence, Fourier transform infrared, dynamic light scattering analysis and transmission electron microscopy. The AgNps presented an average diameter of 15 nm and a zeta potential value of ~ − 28 mV. They were monodispersed and stable for up to 180 days. AgNPs are used as a Hg2+ sensor with high sensitivity and selectivity. The fast, simple and low-cost method is based on changes in the AgNP surface plasmon resonance band (λ ≈ 410 nm) with LOD 6.5 ng/mL (32.5 nM), without functionalization of the AgNPs. The low LOD demonstrates its potential for Hg2+ quantification in environmental samples such as fish, soil, and effluent discharge.

Palavras-Chave: sensors; silver; nanoparticles; sensitivity; synthesis; plasmons; surfaces; silver nitrates; transmission electron microscopy

LOPES, CARLA R.B.; SANTOS JUNIOR, DARIO; SILVA, FLAVIA R. de O.; COURROL, LILIA C. High‑sensitivity Hg2+ sensor based on the optical properties of silver nanoparticles synthesized with aqueous leaf extract of Mimusops coriacea. Applied Physics A: Materials Science and Processing, v. 127, n. 4, p. 1-13, 2021. DOI: 10.1007/s00339-021-04391-2. Disponível em: http://repositorio.ipen.br/handle/123456789/31999. Acesso em: $DATA.

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Abstract: In the work here reported, we have calculated magnetic hyperfine interactions in rare-earth (R) intermetallic compounds by using the free open-source all-electron ELK code. The RCd (R = Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb) series was chosen as a test system because an almost complete set of experimental data on the hyperfine parameters at Cd sites was acquired through the time differential perturbed angular correlation (TDPAC) spectroscopy as previously reported. Moreover, results on magnetic hyperfine field (Bhf ) from WIEN2k code were also reported allowing a qualitative comparison analysis. We emphasize that the utilized version of ELK accounted for the contact field only. Yet, as it is the only contribution expected for Cd site in RCd compounds, the calculated Bhf values are in reasonable agreement with the experimental results. The Spin-orbit coupling when taken into account led to a decrease in deviation from experimental data. Addition, the Hubbard-like term was revealed crucial in order to make Bhf predictions for CeCd, suggesting that this behavior may be associated with a weaker 4f electron localization in Ce.

Palavras-Chave: calculation methods; rare earths; hyperfine structure; cadmium compounds; computer codes; spectroscopy; theoretical data

MACIEL, L.S.; BURIMOVA, A.; PEREIRA, L.F.D.; FERREIRA, W.L.; SALES, T.S.N.; GONÇALVES, V.C.; CABRERA-PASCA, G.A.; SAXENA, R.N.; CARBONARI, A.W. DFT-based calculations of the magnetic hyperfine interactions at Cd sites in RCd (R = rare earth) compounds with the FP-LAPW ELK code. AIP Advances, v. 11, n. 2, p. 025010-1 - 025010-4, 2021. DOI: 10.1063/9.0000161. Disponível em: http://repositorio.ipen.br/handle/123456789/31997. Acesso em: $DATA.

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Abstract: In this study Calcium silicate hydrate based products (CSHP) were synthesized from wet flue gas desulfurization waste (FGD) by alkali fusion followed by hydrothermal treatment. The effect of various factors on the formation of products, such as mineralizing agent, fusion temperature and time, crystallization time and addition of Ca and Si were studied as well as the conditions optimized. The FGD and synthesized materials were characterized by using X-Ray (XRD), Scanning Electron Microscope (SEM), X-ray fluorescence (XFR), among other methods. A fusion temperature of 600 °C with NaOH, fusion duration of 1 h, and a subsequent hydrothermal temperature of 100 °C for a reaction of 24 h were found to be the optimal conditions. In these synthesis conditions, CSHP containing tobermorite and Al-tobermorite was the major phases. The synthesized CSHP revealed high selective uptake for Cs+ in water. The maximum adsorption capacity of Cs+ onto the synthesized material, as calculated from the Langmuir model, was 1949 µmol g-1. The performance on the Cs+ removal in the presence of high Na+ contents was also evaluated. The adsorbent material showed a high Cs+ adsorption capacity in deionized water and a decrease of 56% and 62% in saturated media with the Na+ ions and seawater, respectively. Therefore, CSHP as a higher value-added product can be obtained from a by-product of a coal-fired power plant, which has wide range applications, including for Cs+ removal from wastewater.

Palavras-Chave: flue gas; calcium silicates; hydrates; desulfurization; cesium; adsorption; chemical composition; hydrothermal systems; mineralization

FUNGARO, DENISE A.; GROSCHE, LUCAS; IZIDORO, JULIANA de C. Synthesis of calcium silicate hydrate compounds from wet flue gas desulfurization (FGD) waste. Journal of Applied Materials and Technology, v. 1, n. 2, p. 88-95, 2020. DOI: 10.31258/Jamt.1.2.88-95. Disponível em: http://repositorio.ipen.br/handle/123456789/31991. Acesso em: $DATA.

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Abstract: Uma das preocupações de operadoras privadas de planos de saúde é a diminuição do tempo de atendimento de seus clientes nas centrais de atendimento, regulamentado pela Agência Nacional de Telecomunicações. O presente relato técnico foi delineado como estudo qualitativo, exploratório, descritivo e de pesquisa participante. O processo de aprovação e agendamento do exame de ressonância magnética (RM) de coluna foi modificado desde a etapa da solicitação do beneficiário até a autorização final pela equipe médica. A implantação de um novo fluxo de tomada de decisão, a fim de reduzir ou eliminar as implicações que as lentidões do atendimento podem gerar na saúde dos pacientes, teve como base a inclusão de um Checklist durante as solicitações de RM de coluna. A partir da análise dos resultados, constatou-se que o tempo médio de atendimento com a implantação do Checklist, foi reduzido para 6 minutos. Gerou uma diminuição do tempo médio de atendimento por cliente de 10 para até 6 minutos, com ganho produtivo no processo, relacionado à maior eficiência da operadora e satisfação dos clientes, colaboradores e prestadores de serviços.

Palavras-Chave: health services; magnetic resonance; regulations; organizing; vertebrae; public health; medical establishments; management

BARBOSA, JOSEVANE A.; RAFAEL, DEIVID N.; AQUINO, SIMONE. Redução do tempo médio de atendimento em uma operadora de saúde: otimização do processo de autorização de ressonância magnética de coluna. Revista Inovação, Projetos e Tecnologias - IPTEC, v. 7, n. 1, p. 16-35, 2019. DOI: 10.5585/iptec.v7i1. Disponível em: http://repositorio.ipen.br/handle/123456789/31989. Acesso em: $DATA.

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Abstract: Introduction Radiosynovectomy (RS) with 90Y-hydroxyapatite (90Y-HyA) aims to control knee hemarthrosis in hemophiliac patients to prevent secondary arthropathy. However, knee RS using 153Sm-hydroxyapatite (153Sm-HyA) is considered less suitable due to the lower average soft tissue range and energy of 153Sm for large joints, such as the knees. Purpose The objective of this investigation was to assess the efficacy and safety of knee RS with 153Sm-HyA, compared to 90Y-HyA. Methods Forty patients were prospectively assigned to undergo knee RS with 153Sm-HyA (n = 19) or with 90Y-HyA (n = 21). The frequency of hemarthrosis episodes before and after treatment were compared. Results After six months of knee RS, 153Sm-HyA and 90Y-HyA promoted a similar reduction of hemarthrosis episodes (50% and 66.7%, respectively). However, after 12 months of knee RS, the reduction of hemarthrosis episodes was significantly (p = 0.037) higher using 153Sm-HyA (87.5%) compared to 90Y-HyA (50.0%). This discrepancy was more pronounced (p = 0.002) for 153Sm-HyA compared to 90Y-HyA in adults/adolescents. Conclusion Knee radiosynovectomy with 153Sm-HyA is safe, reduces hemarthrosis episodes after 12 months of treatments, especially in adults/adolescents and even with grades III/IV arthropathy, similar to 90Y-HyA. 90Y-HyA seems to promote better hemarthrosis control in small children.

Palavras-Chave: apatites; hemophilia; hydroxides; inflammation; rheumatic diseases; therapy; samarium 153

SANTOS, ALLAN O.; RICCIARDI, JANAINA B.S.; PAGNANO, RODRIGO; PEREIRA, LUIS F.M.; SAKUMA, EMERSON T.; MATSUDA, MARGARETH M.N.; BERNARDES, EMERSON S.; ARAUJO, ELAINE B.; BRUNETTO, SERGIO Q.; TAKAHASHI, MARIA E.S.; BRUNETTO, EDNA M.; ZULLI, ROBERTO; OZELO, MARGARETH C.; ETCHEBEHERE, ELBA C.S.C. Knee radiosynovectomy with 153Sm‑hydroxyapatite compared to 90Y‑hydroxyapatite: initial results of a prospective trial. Annals of Nuclear Medicine, v. 35, n. 2, p. 232-240, 2021. DOI: 10.1007/s12149-020-01557-5. Disponível em: http://repositorio.ipen.br/handle/123456789/31983. Acesso em: $DATA.

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Abstract: This paper presents a general methodology based on the description of the inductive channel as virtual magnetic transmission-lines (VMGTLs). In comparison with other existing methods, VMGTL approach presents a better physical insight of the channel behavior since the model correctly preserves the energy flow between the transmitting and receiving coils. Besides that, it facilitates the integration into the analysis of highly nonlinear and dispersive structures such as metamaterial (MTM) lenses. Particularly, the virtual-TL analogy clarifies that the enhancement of the transmission gain between any two coils assisted by MTM is not due to an enhanced coupling between the drivers, as usually claimed, but to the emergence of propagating near-field modes supported by the MTM. This approach, by means of a parametric study, also indicates, for the first time, that MTMs could be employed not only for the increasing of power but also of data transfer due to the emergence of a sub-resonant region of minimum distortion. Nonetheless, since both effects are mutually exclusive, no passive MTM structure could simultaneously improve power and data transmission.

Palavras-Chave: metamaterials; power transmission lines; induction; channeling; electromagnetism

ALMEIDA, JORGE V. de; SILVA, EDUARDO C. da; MOSSO, MARBEY M.; SARTORI, CARLOS A.F. A parametric study of inductive SWIPT systems assisted by metamaterial using virtual magnetic TL-based channel modeling. Journal of Microwaves, Optoelectronics and Electromagnetic Applications, v. 20, n. 1, p. 195-207, 2021. DOI: 10.1590/2179-10742021v20i1995. Disponível em: http://repositorio.ipen.br/handle/123456789/31981. Acesso em: $DATA.

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Abstract: Titanium scaffolds with non-toxic β stabilizing elements (Nb and Sn), Ti–34Nb–6Sn (TNS), and with magnesium as spacer (TNS/M), were processed by powder metallurgy, and sintered at 800 ◦C. The X-ray diffraction (XRD) pattern showed that materials are biphasic alloys, presenting 45 to 42% (wt %) in hcp (α-phase) and the rest is bcc (β-phase), and the presence of a slight peak relating to TiO2 in both materials. Pores of approximately 50 μm for TNS and 300 μm to TNS/M were observed in the micrographic analysis by scanning electron microscopy (SEM). The wettability was higher for TNS/M compared to TNS. The elastic modulus was higher for TNS compared to TNS/M. Stem cells derived from equine bone marrow (BMMSCs) were used for in vitro assays. The morphologic and adhesion evaluation after 72 h, carried out by direct contact assay with the materials showed that the BMMSCs were anchored and adhered to the porous scaffolds, in the way the cytoplasmic extension was observed. The cellular migration, using the “wound healing” method, was significant for the groups treated with conditioned medium with materials in 24 h. Osteogenic differentiation of BMMSCs, assessed by calcium deposition and staining with Alizarin Red, was greater in the conditioned medium with TNS/M in 10 days of culture. Since the biological effects was good and the elastic modulus decreased in the system with magnesium is a promising new content titanium alloy for biomedical application.

Palavras-Chave: titanium; magnesium; powder metallurgy; corrosion; biological materials; prostheses; sintering

ROSSI, MARIANA C.; BAYERLEIN, DANIEL L.; BRANDAO, JAQUELINE de S.; PFEIFER, JOAO P.H.; ROSA, GUSTAVO dos S.; SILVA, WILLIAM de M.; MARTINEZ, LUIS G.; SAEKI, MARGARIDA J.; ALVES, ANA L.G. Physical and biological characterizations of TiNbSn/(Mg) system produced by powder metallurgy for use as prostheses material. Journal of the Mechanical Behavior of Biomedical Materials, v. 115, p. 1-10, 2021. DOI: 10.1016/j.jmbbm.2020.104260. Disponível em: http://repositorio.ipen.br/handle/123456789/31979. Acesso em: $DATA.

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Abstract: We present a high-resolution air quality study over São Paulo, Brazil with the EURopean Air Pollution Dispersion - Inverse Model (EURAD-IM) used for the first time over South America simulating detailed features of aerosols. Modeled data are evaluated with observational surface data and a Lidar. Two case studies in 2016 with distinct meteorological conditions and pollution plume features show transport (i) from central South America, associated to biomass burning activities, (ii) from the rural part of the state of São Paulo, (iii) between the metropolitan areas of Rio de Janeiro and São Paulo (MASP) either through the Paraíba Valley or via the ocean, connecting Brazil's two largest cities, (iv) from the port-city Santos to MASP and also from MASP to the city Campinas, and vice versa. A Pearson coefficient of 0.7 was found for PM10 at MASP CENTER and EURAD-IM simulations vary within the observational standard deviation, with a Mean Percentual Error (MPE) of 10%. The model's vertical distributions of aerosol layers agree with the Lidar profiles that show either characteristics of long-range transported biomass burning plumes, or of local pollution. The distinct transport patterns that agree with satellite Aerosol Optical Death and fire spot images as well as with the ground-based observations within the standard deviations, allows us exploring patterns of air pollution in a detailed manner and to understand the complex interactions between local to long-range transport sources.

Palavras-Chave: air pollution; urban areas; evaluation; aerosols; atmospheres; air pollution monitoring; combustion; environmental impacts

DUARTE, EDICLE de S.F.; FRANKE, PHILIPP; LANGE, ANNE C.; FRIESE, ELMAR; LOPES, FABIO J. da S.; SILVA, JONATAN J. da; REIS, JEAN S. dos; LANDULFO, EDUARDO; SILVA, CLAUDIO M.S. e; ELBERN, HENDRIK; HOELZEMANN, JUDITH J. Evaluation of atmospheric aerosols in the metropolitan area of São Paulo simulated by the regional EURAD-IM model on high-resolution. Atmospheric Pollution Research, v. 12, n. 2, p. 451-469, 2021. DOI: 10.1016/j.apr.2020.12.006. Disponível em: http://repositorio.ipen.br/handle/123456789/31973. Acesso em: $DATA.

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Abstract: In the present work, the radioimmunoconjugates 111In-DTPA-trastuzumab and 177Lu-DOTA-trastuzumab were evaluated regarding the influence of the chelating agents on the physical–chemical parameters and human epidermal growth factor receptor 2 (HER2) tumor cell binding. Data showed that both chelating agents, at predetermined molar ratios (antibody:chelator 􀀀 1:10 and 1:20), did not influence the immunoconjugates integrity, the radiolabeling process and the radiolabeled antibodies stability. However, differences were observed in the lipophilic feature between DOTA and DTPA radioimmunoconjugates and in the specific binding to SK-BR-3 tumor cells (HER2 positive). Therefore, this study showed the importance of assessing the influence of chelating agents and their molar ratios in the development process of radioimmunoconjugates.

Palavras-Chave: tumor cells; neoplasms; drugs; therapeutic uses; radioimmunotherapy; chelating agents; radioisotopes

MIRANDA, ANA C.C.; DURANTE, ANA C.R.; FUSCALDI, LEONARDO L.; BARBEZAN, ANGELICA B.; LIMA, CILENE R. de; PERINI, EFRAIN; ARAUJO, ELAINE B. de. Anti-HER2 monoclonal antibody based-radioimmunoconjugates: assessment of the chelating agent influence. Bioorganic & Medicinal Chemistry, v. 33, p. 1-9, 2021. DOI: 10.1016/j.bmc.2021.115996. Disponível em: http://repositorio.ipen.br/handle/123456789/31971. Acesso em: $DATA.

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Abstract: In this work, the photoluminescence properties of CaSO4 crystals co-doped with terbium and silver from silver oxide or silver nanoparticles (NPs) in different concentrations are investigated. Phosphors are obtained by means of a slow evaporation route and calcined at 600 °C for 1 h. X-ray diffraction analysis shows the formation of a single-phase anhydrite structure with orthorhombic symmetry. The photoluminescence properties are investigated using vacuum ultraviolet, ultraviolet and X-ray excitation. All luminescent measurements reveal the characteristic emissions of Tb3+. The analyses using excitation with ultraviolet light show that the Ag NPs are able to generate structural defects more satisfactorily compared to CaSO4:Tb with silver oxide. We also observe that higher concentrations of Ag increase the Tb3+ emission intensity, while higher concentrations of Ag NPs decrease it. The good stability of CaSO4 results in an efficient energy transfer from the host lattice to the activator under X-ray excitation, with the NPs contributing to the increase in luminescent intensity. Investigation of the terbium valence in the CaSO4 host shows a complete reduction of the Tb4+ present in Tb4O7 to Tb3+, as indicated by the X-ray absorption near edge structure. The vacuum ultraviolet excitation spectra reveal three broad bands, attributed to the charge-transfer excitations within SO42− complexes and to the 4f8 → 4f75d1 transitions on Tb3+. Our results also reveal that silver particles are responsible for generating deeper capture centers.

Palavras-Chave: calcium sulfates; terbium; silver; phosphors; doped materials; photoluminescence; optical properties; crystals; nanoparticles; x-ray diffraction; ultraviolet radiation

SILVA, ANDERSON M.B.; SILVEIRA, WELLISSON S.; MATOS, TAWANY S.; JUNOT, DANILO O.; REZENDE, MARCOS V.S.; SOUZA, DIVANIZIA N. Effect of terbium and silver co-doping on the enhancement of photoluminescence in CaSO4 phosphors. Optical Materials, v. 111, p. 1-8, 2021. DOI: 10.1016/j.optmat.2020.110717. Disponível em: http://repositorio.ipen.br/handle/123456789/31969. Acesso em: $DATA.

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Abstract: Subcritical noise experiments at frequencies up to 100 kHz employing two distinct boron dilution in the reactor tank water (286.8 and 578.6 ppm of natural boron) were performed in the IPEN/MB-01 reactor. The Auto Power Spectral Densities (APSD) were inferred employing the IPEN/MB-01 Correlator and were best described by a four-mode decay model up to about 70 kHz. The analyses reveal that the first two modes were related to thermal neutron and the other two to the fast ones. The coupling between thermal and fast neutrons was weak, and they could be considered uncoupled. A two-region two-group kinetic model was built and for the first time important parameters, such as the subcritical reactivities, generation times, and the prompt neutron decay constants all in the core and reflector in the 286.8 ppm case were inferred. The experiments can be considered unique of its kind and the theory/experiment comparisons reached good agreements.

Palavras-Chave: zero power reactors; reactor noise; ipen-mb-1 reactor; spectral density; criticality; frequency measurement; lifetime; neutrons

SANTOS, DIOGO F. dos; SANTOS, ADIMIR dos. Zero-power noise up to 100 kHz in the IPEN/MB-01 research reactor facility. Annals of Nuclear Energy, v. 152, p. 1-16, 2021. DOI: 10.1016/j.anucene.2020.107974. Disponível em: http://repositorio.ipen.br/handle/123456789/31967. Acesso em: $DATA.

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Abstract: Advances toward new materials for dosimetry application is essential to enhance quality assurance and quality improvement practices based on radiation protection concept. Face to this challenge the present work reports an approach to produce thulium-yttria nanoparticles with electron paramagntic resonance response by an alternative hydrothermal synthesis based on a relative low temperature and pressure. Distinct compositions of thulium-yttria nanoparticles with up to 2 at.%Tm (at.%, atomic percentage) were prepared and characterized by XRD, SEM, PCS, and EPR. The proposed synthesis method followed by thermal treatment of the precursor powder at 1100 ◦C for 2 h provided thulium-yttria nanoparticles with rounded shape, cubic C-type structure, and mean particle size (d50) less than 160 nm. Among all compositions formed, thulium-yttria nanoparticles prepared with 0.1%Tm presented the most remarkable EPR response. The production of fine thulium-yttria nanoparticles with EPR response supply meaningful parameters to advance in the formation of new dosimetry materials based on rare earths.

Palavras-Chave: dosimetry; thulium oxides; yttrium; nanoparticles; rare earths; electron paramagnetic resonance; ceramics

SANTOS, S.C.; RODRIGUES JUNIOR, O.; CAMPOS, L.L. Towards a new promising dosimetric material from formation of thulium-yttria nanoparticles with EPR response. Materials Chemistry and Physics, v. 259, p. 1-7, 2021. DOI: 10.1016/j.matchemphys.2020.124005. Disponível em: http://repositorio.ipen.br/handle/123456789/31965. Acesso em: $DATA.

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Abstract: Ipomoea carnea is a toxic plant found in Brazil and other tropical countries. The plant contains the alkaloids calystegines and swainsonine, which inhibit key cellular enzymes and cause systematic cell death. It is known that swainsonine is excreted in the amniotic fluid of dams exposed to the plant. Thus, the aim of this study was to verify whether the toxic effect of I. carnea on fetuses is due to exclusively the passage of the active principle of the plant through the placenta, or if the placentotoxic effect of swainsonine could collaborate in the adverse effects observed in the fetus. The teratogenic effects of exposure to the toxic principles of I. carnea were evaluated not only using the conventional protocol but also at later stages in the postnatal developmental period. Females were treated, from gestation day (GD) 6 until GD19, with 0.0, 1.0, 3.0 or 7.0 g/kg body weight of I. carnea dry leaves. The plant did not induce changes in reproductive performance or biochemical profile of the dams. Dams that received the highest dose of I. carnea showed cytoplasmic vacuolization in the liver, kidney and placental tissue. I. carnea promoted different lectin binding patterns in different areas of placental tissue. No fetal skeletal or visceral malformations was observed. The postnatal evaluation revealed a lower litter weight and a lower pup body weight one day after birth in the group that received the highest dose of I. carnea. Physical milestones were unaffected by the treatments. Female pups from all experimental groups exhibited a delay in achieving a negative geotaxis response. The results show that the toxic principle of I. carnea produces injury in utero in mothers and fetuses, but these deleterious effects were better demonstrated using postnatal evaluation.

Palavras-Chave: toxicity; plants; reproduction; placenta; fetuses; teratogens; alkaloids; bioassay; tropical regions

GOTARDO, ANDRE T.; LIPPI, LUCIANA L.; VIOLIN, KALAN B.; BEVILACQUA, ESTELA M.A.F.; GORNIAK, SILVANA L. The effect of Ipomoea carnea on maternal reproductive outcomes and fetal and postnatal development in rats. Toxicon, v. 190, p. 3-10, 2021. DOI: 10.1016/j.toxicon.2020.11.012. Disponível em: http://repositorio.ipen.br/handle/123456789/31963. Acesso em: $DATA.

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Abstract: The response of thin diodes (SFH206k) as dosimeters has been investigated employing the beam of an electron accelerator within the dose rate range of 2–8 kGy/s and accumulated doses up to 100 kGy. These devices, operating in the short-circuit mode and under industrial irradiation conditions, deliver current signals nonlinearly dependent on the dose rate, whichever the dose history of the diodes, due to the high density of the generated electron-hole pairs herein achieved. Despite this nonlinearity, the dose rate response is stable and characterized by current signals with repeatability better than 2.0%, regardless of the accumulated dose. It is also found that the dose responses are quite linear with sensitivities slightly dependent on the accumulated dose at a constant dose rate. The decrease in the charge sensitivity, taking as reference that obtained before any radiation damage, reaches only 9% (k = 2) at 100 kGy, which is much smaller than the values reported in the literature. From this low aging and the repeatability of both dose rate and dose responses, it seems that the photodiode under investigation is a low budget alternative, good enough for routine dosimetry, provided it has been previously calibrated in the same processing facility.

Palavras-Chave: photodiodes; dosimetry; electron beams; dosemeters; electron dosimetry; si semiconductor detectors; dose rates

GONCALVES, JOSEMARY A.C.; MANGIAROTTI, ALESSIO; ASFORA, VIVIANE K.; KHOURY, HELEN J.; BUENO, CARMEN C. The response of low-cost photodiodes for dosimetry in electron beam processing. Radiation Physics and Chemistry, v. 181, p. 1-8, 2021. DOI: 10.1016/j.radphyschem.2020.109335. Disponível em: http://repositorio.ipen.br/handle/123456789/31961. Acesso em: $DATA.

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Abstract: Commercial PIN photodiodes, repurposed as particle detectors, have received a lot of attention along the past decades because they can offer a low-cost solution suitable for several applications. The BPX-65 photodiode has been chosen because of its interesting features for measuring electrons in a harsh radiation environment close to the beam of an accelerator. Its electrical characterisation and its application to photon spectrometry have been presented in the companion paper I. Here, its response function (RF) to electrons is investigated using the beam from an electron accelerator with a small energy spread. The empirical expressions for the RF available in the literature have been improved, simplified, and combined to obtain a final form with 7 free parameters: 4 non-linear and 3 linear. A special fitting procedure, which takes advantage of the presence of the linear parameters, is described. The behaviour of these parameters with beam energy and bias is investigated to uncover the physical origin of the three components included in the proposed RF. The interpretation of the features of the spectra is confirmed by Monte Carlo simulations carried out employing the general-purpose PENELOPE/penEasy package. To take into account the charge-collection properties of the device, a simple model has been implemented and is compared to data. It has then been possible to estimate the thickness of the partially dead layer from the experiment.

Palavras-Chave: photodiodes; silicon; monte carlo method; plasma; experiment planning; response functions

MANGIAROTTI, A.; PETRI, A.R.; MALAFRONTE, A.A.; GONCALVES, J.A.C.; BARROS, S.F.; BUENO, C.C.; FERNANDEZ-VAREA, J.M.; MAIDANA, N.L.; MARTINS, M.N.; VANIN, V.R. A low-cost small-size commercial PIN photodiode: II. Comparison of measurements with monoenergetic electrons to analytical expressions and Monte Carlo simulations. Radiation Physics and Chemistry, v. 182, p. 1-20, 2021. DOI: 10.1016/j.radphyschem.2020.109102. Disponível em: http://repositorio.ipen.br/handle/123456789/31959. Acesso em: $DATA.

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Abstract: The concentrations of Platinum (Pt), Rhodium (Rh) and Palladium (Pd) were evaluated from a highly impacted estuary in Brazil influenced by industrial pole, highway traffic and sewage outfall. The Santos-São Vicente region presents important economic activities derived from a largest harbor of Latin America and an industrial pole surrounded by intensive highway traffic. Values of Rh varied from 0.08 to 1.7 ng g−1 with highest values at stations impacted by domestic waste. Pt ranged from 0.15 to 40.3 ng g−1 with highest concentrations located close to the ferryboat traffic. Pd levels varied from 1.05 to 22.0 ng g−1 with values >5 ng g−1 in 50% of the stations. The spatial distribution of PGEs was not always directly associated with muddy sediments, because high PGE levels found even in sandy sediments. Pollution indexes, including anthropogenic factor (AF), geoaccumulation index (Igeo), Enrichment factor (EF), and Pollution Load Index (PLI) were used for evaluating contaminant potential. Based on EF, Igeo, and PLI, 50% of samples of the sediments from Santos-São Vicente Estuarine System (SSV) were classified with significant to strong PGE contamination. All stations on the Santos Channel (SC), São Vicente Channel (SVC) and Bertioga Channel (BC) had AF higher than 80% in at least one of PGE elements, as showed in station 2A, which presented AF <50% for Rh and Pd and 86% for Pt. Despite high anthropogenic enrichment, no correlations among PGE elements were observed in surface sediments. Only two stations presented Pd/Pt, Pt/Rh, and Pd/Rh typical ratios of auto catalyst (st. 14 and Piaçaguera) both located in the vicinity of highways. This could be due to the PGE deposition process in road dust, soil, and water as well as the biogeochemical cycling of PGEs involving organic metallic and inorganic complexes formed in the estuarine and seawaters.

Palavras-Chave: estuaries; sediments; indexes; environment; coastal regions; water pollution; coastal waters; platinum; rhodium; palladium; chemical composition

BERBEL, GLAUCIA B.B.; HORTELLANI, MARCOS A.; SARKIS, JORGE E. de S.; CHIOZZINI, VITOR G.; FAVARO, DEBORAH I.T.; SUTTI, BRUNO O.; SAKAZAKI, NIXON C.; BRAGA, ELISABETE de S. Emerging contaminants (Rh, Pd, and Pt) in surface sediments from a Brazilian subtropical estuary influenced by anthropogenic activities. Marine Pollution Bulletin, v. 163, p. 1-13, 2021. DOI: 10.1016/j.marpolbul.2020.111929. Disponível em: http://repositorio.ipen.br/handle/123456789/31957. Acesso em: $DATA.

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