Abstract: Dust particles originating from arid desert regions can be transported over long distances, presenting severe risks to climate, environment, social economics, and human health at the source and downwind regions. However, there has been a dearth of continuous diurnal observations of vertically resolved mass concentration and optical properties of dust aerosols, which hinders our understanding of aerosol mixing, stratification, aerosol-cloud interactions, and their impacts on the environment. To fill the gap of the insufficient observations, to the best of our knowledge, this work presents the first high-spectral-resolution lidar (HSRL) observation providing days of continuous profiles of the mass concentration, along with particle linear depolarization ratio (PLDR), backscattering coefficient, extinction coefficient and lidar ratio (LR), simultaneously. We present the results of two strong dust events observed by HSRL over Beijing in 2021. The maximum particle mass concentrations reached (1.52 ± 3.5) x103 μg/m3 and (19.48 ± 0.36) x103 μg/m3 for the two dust events, respectively. The retrieved particle mass concentrations and aerosol optical depth (AOD) agree well with the observation from the surface PM10 concentrations and sun photometer with correlation coefficients of 0.90 and 0.95, respectively. The intensive properties of PLDR and LR of the dust aerosols are 0.31 ± 0.02 and 39 ± 7 sr at 532 nm, respectively, which are generally close to those obtained from observations in the downwind areas. Moreover, inspired by the observations from HSRL, a universal analytical relationship is discovered to evaluate the proportion of dust aerosol backscattering, extinction, AOD, and mass concentration using PLDR. The universal analytical relationship reveals that PLDR can directly quantify dust aerosol contribution, which is expected to further expand the application of polarization technology in dust detection. These valuable observations and findings further our understanding of the contribution of dust aerosol to the environment and help supplement dust aerosol databases.

Palavras-Chave: dusts; aerosols; particles; optical radar; environmental impacts

XIAO, DA; WANG, NANCHAO; CHEN, SIJIE; WU, LINGYUN; MULLER, DETLEF; VESELOVSKII, IGOR; LI, CHENGCAI; LANDULFO, EDUARDO; SIVAKUMAR, VENKATARAMAN; LI, JING; CHE, HUIZHENG; FANG, JING; ZHANG, KAI; WANG, BINYU; CHEN, FEITONG; HU, XIANZHE; LI, XIAOTAO; LI, WEIZE; TONG, YICHENG; KE, JU; WU, LAN; LIU, CHONG; LIU, DONG. Simultaneous profiling of dust aerosol mass concentration and optical properties with polarized high-spectral-resolution lidar. Science of the Total Environment, v. 872, p. 1-13, 2023. DOI: 10.1016/j.scitotenv.2023.162091. Disponível em: http://repositorio.ipen.br/handle/123456789/34002. Acesso em: $DATA.

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Abstract: Photobiomodulation (PBM) has been clinically used for the prevention and treatment of oral mucositis (OM). The effect of red and near-infrared wavelengths on OM repair is still misunderstood. The aim of this study was to compare the clinical effect and tissue changes caused by 660 nm and 780 nm exposure in an experimental model of OM. Rats were submitted to gamma irradiation for induction of OM lesions and treated with 660 nm or 780 nm lasers with the same dosimetry parameters (30 mW, 7.5 J/cm2, 10 s, spot size = 0.04 mm, irradiation every two days). Clinical assessment of OM severity and histopathological analyses was performed after 8, 14, and 20 days of the ionizing radiation. OM severity was reduced in the PBM groups, especially when the red laser was used. The histopathological pattern was similar between the PBM groups, showing advanced re-epithelization and more pronounced angiogenesis and collagen deposition compared to the control. The 660 nm group showed a greater collagen matrix area than the 780 nm group at 14 days. In conclusion, PBM at 660 nm and 780 nm improved the repair of ionizing radiation-induced OM. Both wavelengths activated the angiogenesis and collagen deposition, but these tissue effects were more pronounced when 660 nm was used.

Palavras-Chave: oral cavity; mucous membranes; injuries; radiotherapy; lasers; ionizing radiations

ANDRADE, MAIRA F.; SARDO, ARIANE V.N.; BENETTI, CAROLINA; SICCHIERI, LETICIA B.; CORREA, LUCIANA; ZEZELL, DENISE M. Comparison of two light wavelengths (λ = 660 nm and λ = 780 nm) in the repair process of oral mucositis induced by ionizing radiation: clinical and microscopic evaluations in rats. Photonics, v. 10, n. 1, p. 1-13, 2023. DOI: 10.3390/photonics10010016. Disponível em: http://repositorio.ipen.br/handle/123456789/34000. Acesso em: $DATA.

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Abstract: Ancient pottery fragments from the Tunata-hill site in Churajon archaeological complex, Arequipa, Peru, were dated by means of luminescence techniques such as thermoluminescence (TL) and optically stimulated luminescence (OSL) in order to provide absolute chronology. For TL, additive and regenerative methods were performed. For OSL a regenerative method was carried out for IRSL dating. A rigorous description of the study area and its context has been made. The ages of the samples were found to be between 0.50 ± 0.06 ky and 0.49 ± 0.03 ky for TL methods, and 0.49 ± 0.02 ky for OSL methods. On average, the estimated age by TL and OSL techniques is 490 ± 70 yr (1600 AD and 1460 AD). This means that Churajon ceramics under study would belong to the Late periods which corresponds to the Inca region, and the North sub-region of the Late Churajon phase, and the beginning of European colonization in Peru. X-ray fluorescence technique (XRF) analysis has shown the main presence of Fe (39.5%), Si (30.0%), and Al (10.4%) in fine pottery powder. Furthermore, the electron paramagnetic resonance (EPR) technique was used to study the firing temperature using the iron signal (Fe3+) as a firing temperature reference. The firing temperature of ceramics was found to be around 550 ± 50 °C.

Palavras-Chave: ceramics; archaeological sites; thermoluminescence; age estimation; temperature dependence; photoluminescence; x-ray fluorescence analysis; cultural objects

PACOMPIA, YOLANDA; SUPO-RAMOS, JUSTO G.; GONZALES-LORENZO, CARLOS D.; CALLO-ESCOBAR, DARWIN J.; ROCCA, RENE R.; PASTRANA, ELIZABETH C.; GOMES, MONISE B.; SILVA-CARRERA, BETZABEL N.; WATANABE, S.; AYCA-GALLEGOS, OSCAR; AYALA-ARENAS, JORGE S. Luminescence dating and firing temperature determination of ancient ceramics fragments from the Tunata-hill site in the Churajon archaeological complex in Arequipa, Peru. Radiation Physics and Chemistry, v. 204, p. 1-11, 2023. DOI: 10.1016/j.radphyschem.2022.110725. Disponível em: http://repositorio.ipen.br/handle/123456789/33998. Acesso em: $DATA.

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Abstract: This study investigates the high temperature oxidation behaviour of a Ni–20Cr-1.2Si (wt.%) alloy in steam from 1200 °C to 1350 °C by Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). The results demonstrate that exposed Ni-based alloy developed a thin oxide scale, consisted mainly of Cr2O3. The oxidation kinetics obtained from the experimental results was applied to evaluate the hydrogen generation considering a simplified reactor core model with different cladding alloys following an unmitigated Loss-Of-Coolant Accident (LOCA) scenario in a hypothetical Small Modular Reactor (SMR). Overall, experimental data and simulations results show that both Fe-based and Ni-based alloys may enhance cladding survivability, delaying its melting, as well as reducing hydrogen generation under accident conditions compared to Zr-based alloys. However, a substantial neutron absorption occurs when Ni-based alloys are used as cladding for current uranium-dioxide fuel systems, even when compared to Fe-based alloys.

Palavras-Chave: fuel-cladding interactions; nickel alloys; stainless steels; oxidation; temperature range 0400-1000 k; cladding

AVELAR, ALAN M.; CAMARGO, FABIO de; SILVA, VANESSA S.P. da; GIOVEDI, CLAUDIA; ABE, ALFREDO; MOURAO, MARCELO B. Effectiveness of Ni-based and Fe-based cladding alloys in delaying hydrogen generation for small modular reactors with increased accident tolerance. Nuclear Engineering and Technology, v. 55, n. 1, p. 156-168, 2023. DOI: 10.1016/j.net.2022.09.002. Disponível em: http://repositorio.ipen.br/handle/123456789/33996. Acesso em: $DATA.

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Abstract: Here, Pd nanoparticles supported on ZnO were prepared by the alcohol-reduction and the borohydride-reduction methods, and their efficiency towards the photocatalytic conversion of methane under mild conditions were evaluated. The resulting Pd/ZnO photocatalysts were characterized by X-ray fluorescence, X-ray diffraction, X-ray photoelectron spectroscopy, UV–Vis, and transmission electron microscopy. The reactions were performed with the photocatalysts dispersed in water in a bubbling stream of methane under UV-light illumination. The products formed were identified and quantified by gas chromatography (GC-FID/TCD/MSD). The principal products formed were C2H6 and CO2 with minor quantities of C2H4 and CO. No H2 production was observed. The preparation methods influenced the size and dispersion of Pd nanoparticles on the ZnO, affecting the performance of the photocatalysts. The best performance was observed for the photocatalyst prepared by borohydride reduction with 0.5 wt% of Pd, reaching a C2H6 production rate of 686 µmol·h−1·g−1 and a C2H6 selectivity of 46%.

Palavras-Chave: photocatalysis; methane; zinc oxides; palladium; nanoparticles

MACHADO, ARTHUR P.; CARMINATI, SAULO A.; JANUARIO, ELIANE R.; FERREIRA, PATRICIA S.; VAZ, JORGE M.; SPINACE, ESTEVAM V. Photocatalytic methane conversion over Pd/ZnO photocatalysts under mild conditions. Methane, v. 2, n. 1, p. 44-55, 2023. DOI: 10.3390/methane2010003. Disponível em: http://repositorio.ipen.br/handle/123456789/33994. Acesso em: $DATA.

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Abstract: Due to its economic, social, and environmental importance, Santos and São Vicente Estuarine System is largely studied for almost two decades. Although many studies have been conducted, none of them tried to relate past activities to actual ones. This study provides an evaluation of the contamination on vintage superficial sediment samples investigating sediment contamination patterns over the years to help to understand future trends in metal contamination in this area. Thus, this study aims to assess levels of trace elements and rare earth elements (REEs) on samples collected in two seasonal periods of 2005 and 2006 (summer and winter). In each campaign, 16 surface samples were collected onboard R/V Veliger II, and trace elements and REEs were analyzed by neutron activation analysis. Results of metals presented similar levels over the years and it was not related to the port's activities since the levels did now increase following the total movement of containers. In addition, the enrichment of light REEs could indicate anthropogenic activities from steel plants, phosphate fertilizers, and the phosphogypsum piles. The system undergoes through many human pressures and constant monitoring over time it is important to avoid overloading the resilience capacity of the estuarine system because the expansion of port, industry, and urbanization is inevitable. From the results obtained, it was possible to conclude that SSVES undergoes more likely anthropogenic pressures from industrial activities and domestic effluents rather than port activity.

Palavras-Chave: economic analysis; estuaries; water pollution; sediments; trace amounts; elements

KIM, BIANCA S.M.; AMORIM, EDUARDO P.; SILVA, PAULO S.C.; FIGUEIRA, RUBENS, C.L.; BRAGA, ELISABETE S.; FAVARO, DEBORAH I.T. Vintage analysis on superficial sediments to predict future trends in metal contamination of Santos and São Vicente Estuarine System. Journal of Trace Elements and Minerals, v. 3, p. 1-8, 2023. DOI: 10.1016/j.jtemin.2023.100049. Disponível em: http://repositorio.ipen.br/handle/123456789/33992. Acesso em: $DATA.

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Abstract: In this work, the variation in the structural and electrical properties of lithium-doped sodium titanate, obtained from an ultrafast (15 min) microwave-assisted synthesis has been reported. X-ray diffraction and Rietveld analysis have been done to identify the present phases, their composition, and lattice parameters. Na2Ti3O7 was identified as the major phase, while Na2Ti6O13 was obtained as a secondary phase in all samples. The phase composition usually varies depending on the content of the doping element. In the sample with 0.5% lithium ions, an additional phase corresponding to NaLiTi3O7 appeared. The microstructure of the ceramic samples showed an increase in the grains size and the appearance of small particles on the surface of the grains. This effect becomes more evident for the samples with 0.5% Li. Finally, the electrical properties of the ceramic samples studied were favored with an increase in doping and σdc values of 1.94 × 10− 5 S cm− 1, 2.51 × 10− 5 S cm− 1, and 4.00 × 10− 5 S cm− 1 were determined for Na2 − xLixTi3O7 with x = 0.0%, 0.1%, 0.5% of Li+.

Palavras-Chave: sodium compounds; titanates; microwave radiation; lithium; doped materials

MELO, A.D.; SILVA, J.P. da; NOBRE, F.X.; COSTA, S.; SALES JUNIOR, J.C.C.; ANGLADA-RIVERA, J.; GUERRERO, F.; PAULA, M.M. da S.; SOUZA, R.F.B. de; PENA-GARCIA R.; AGUILERA, L.; LEYET, Y. Synthesis microwave-assisted: fast method to obtain lithium-doped sodium titanate. Journal of Materials Science: Materials in Electronics, v. 34, n. 6, p. 1-10, 2023. DOI: 10.1007/s10854-023-09948-w. Disponível em: http://repositorio.ipen.br/handle/123456789/33990. Acesso em: $DATA.

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Abstract: This work presents the structural characteristics and the dosimetric properties under ionizing radiation of the lithium silicate (LSO) (LSO) phosphor. The structure of the synthesized material was determined by X-ray diffraction (XRD) method and Rietveld refinement method. The dosimetric properties of LSOLSO in the form of pellets were studied by thermoluminescence (TL) under the effect of different doses of γ-irradiation. The phosphor exhibited a TL emission curve with four TL peaks centered at 100, 182, 250 and 290 °C, with a light emission band centered at 385 nm. The TL dose-dependent γ-radiation dose response of the TL peak at 182 °C was linear in the low-dose region, from the order of mGy to 50 Gy. In addition, the phosphor exhibits lower fading, good reproducibility, and sensitivity of the order of commercial TLD-100 dosimeters.

Palavras-Chave: lithium silicates; thermoluminescence; synthesis; dosimetry

CANO, NILO F.; AYNAYA-CAHUI, SANDRA C.; VILCA, ZAIDA V.; ROCCA, RENE R.; GUNDU RAO, T.K.; CARRERA, BETZABEL N.S.; LOPEZ-GONZALES, ALEJANDRO H.; JAVIER-CCALLATA, HENRY S.; AYALA-ARENAS, JORGE S. Preparation and study of the main dosimetric properties by TL of sintered lithium silicate pellets. Journal of Luminescence, v. 255, p. 1-7, 2023. DOI: 10.1016/j.jlumin.2022.119580. Disponível em: http://repositorio.ipen.br/handle/123456789/33988. Acesso em: $DATA.

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Abstract: Luminescent BaMO4:xmol%Eu3+ materials (M: Mo or W, and x: 0, 2, 4, 6, 8, and 10 mol%) were successfully obtained by a coprecipitation method at room temperature without additional thermal treatment, leading to highly crystalline materials with reduced reaction times and low manufacturing cost. Structural analyses by powder X-ray diffraction and vibrational Raman techniques of the [WO4]2- and [MoO4]2- groups confirm a characteristic scheelite-type structure. The results indicate an average crystallite size at around 30 nm, and a highly pure phase has been supported by Rietveld refinement. SEM-EDS data of BaMO4:xmol%Eu3+ materials identified polycrystalline particles with bipyramidal-like morphology and homogeneous europium ion distribution. Additionally, the band gap energy (Eg) of barium molybdate and tungstate materials were calculated from reflectance data by the single-constant Kubelka-Munk function. Furthermore, the emission intensity, lifetime, and intrinsic emission quantum yield (Q Eu3+/Eu3+) of the materials have been determined and discussed. The luminescent properties of these materials are significantly influenced by the LMCT excitation bands (O2- → Mo6+, W6+, and Eu3+) as well as their intense red emission bands assigned to Eu3+ transitions. The experimental intensity parameter values Ω2 and Ω4 were evaluated from the emission spectra, using the magnetic dipole 5D0 → 7F1 transition as the standard reference. It was observed that the Ω2 values are much higher than the Ω4 values. This result is related to the fact that the 5D0 → 7F2 transition presents a much higher intensity than 5D0 → 7F1 one suggesting a low local symmetry around the Eu3+ ion, which might be due to angular distortions in the local coordination geometry. The high Q Eu3+/Eu3+ values (60–79%) indicated an overall high emission intensity for the prepared phosphors. These are special photonic features of the Eu3+-doped molybdate and tungstate, suggesting they could be suitable for luminescent materials applications.

Palavras-Chave: luminescence; europium; tungstates; molybdates; coprecipitation; phosphors

MOREIRA, RENAN P.; FRANCISCO, LEONARDO H.C.; COSTA, ISRAEL F.; BARBOSA, HELLIOMAR P.; TEOTONIO, ERCULES E.S.; FELINTO, MARIA C.F.C.; MALTA, OSCAR L.; BRITO, HERMI F. Luminescence properties of BaMO4:Eu3+ (M: Mo or W) phosphors derived from co-precipitation reaction. Journal of Alloys and Compounds, v. 937, p. 1-11, 2023. DOI: 10.1016/j.jallcom.2022.168408. Disponível em: http://repositorio.ipen.br/handle/123456789/33986. Acesso em: $DATA.

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Abstract: Chitosan films are commonly used for wound dressing, provided that this polymer has healing, mucoadhesiveness and antimicrobial properties. These properties can be further reinforced by the combination of chitosan with polysaccharides and glycoproteins present in aloe vera, together with copaiba oleoresin’s pharmacological activity attributed to sesquiterpenes. In this work, we developed chitosan films containing either aloe vera, copaiba oil or both, by casting technique, and evaluated their microbial permeation, antimicrobial activity, cytotoxicity, and in vivo healing potential in female adult rats. None of the developed chitosan films promoted microbial permeation, while the cytotoxicity in Balb/c 3 T3 clone A31 cell line revealed no toxicity of films produced with 2 % of chitosan and up to 1 % of aloe vera and copaiba oleoresin. Films obtained with either 0.5 % chitosan or 0.5 % copaiba oleoresin induced cell proliferation which anticipate their potential for closure of wound and for the healing process. The in vivo results confirmed that tested films (0.5 % copaiba-loaded chitosan film and 0.5 % aloe vera-loaded chitosan film) were superior to a commercial dressing film. For all tested groups, a fully formed epithelium was seen, while neoformation of vessels seemed to be greater in formulations-treated groups than those treated with the control. Our work confirms the added value of combining chitosan with aloe vera and copaiba oil in the healing process of wounds.

Palavras-Chave: medicinal plants; trees; polysaccharides; glycoproteins; wounds; healing

GENESI, BIANCA P.; BARBOSA, RAQUEL de M.; SEVERINO, PATRICIA; RODAS, ANDREA C.D.; YOSHIDA, CRISTIANA M.P.; MATHOR, MONICA B.; LOPES, PATRICIA S.; VISERAS, CESAR; SOUTO, ELIANA B.; SILVA, CLASSIUS F. da. Aloe vera and copaiba oleoresin-loaded chitosan films for wound dressings: microbial permeation, cytotoxicity, and in vivo proof of concept. International Journal of Pharmaceutics, v. 634, p. 1-12, 2023. DOI: 10.1016/j.ijpharm.2023.122648. Disponível em: http://repositorio.ipen.br/handle/123456789/33984. Acesso em: $DATA.

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Abstract: This paper evaluates corn starch aerogels, studying different crosslinking agent (trisodium citrate) concentrations (1:1, 1:1.5, and 1:2) and sorption conditions (contact time, adsorbent weight, and initial concentration) regarding the potentially toxic elements (PTEs) [Cd(II) or Zn(II)] adsorption of the aqueous systems. Besides, other properties of aerogels, such as structural properties, specific surface area, and mechanical performance, were evaluated. For adsorption results, better values were observed in adsorption capacity and efficiency for the initial concentration of 100 ppm. In addition, an adsorption time of 12 h and an adsorbent weight of 3.0 g obtained better results due to the possible balance in this time and the high specific surface area available for Cd(II) adsorption. As for the type of adsorbent, the Aero 1:1.5 sample (intermediate crosslinking agent concentration) obtained better results, possibly due to the high porosity, smaller pore sizes, high pore density, and high specific surface area (198 m2·g−1). In addition, hydroxyl groups in the starch aerogel removed Cd(II) ions with 30 % adsorption efficiency. Lastly, Aero 1:1.5 obtained a high mechanical strength at compression and a satisfactory compressive modulus. In contrast, starch aerogels did not absorb the Zn(II) ion.

Palavras-Chave: maize; starch; gels; adsorption; elements; toxic materials

CAMANI, PAULO H.; MIDHUN DOMINIC, C.D.; PARRA, DUCLERC F.; MALTEZ, HELOISA F.; ROSA, DERVAL S. Divalent metal ion removal from simulated water using sustainable starch aerogels: effect of crosslinking agent concentration and sorption conditions. International Journal of Biological Macromolecules, v. 226, p. 628-645, 2023. DOI: 10.1016/j.ijbiomac.2022.11.308. Disponível em: http://repositorio.ipen.br/handle/123456789/33982. Acesso em: $DATA.

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Abstract: Direct formate fuel cells have gained increasing attention since formate can be obtained by CO2 reduction, being shown as a renewable power source. This paper reports the use of Pd nanoparticles supported on physical mixtures of Vulcan carbon and TiO2 in different ratios and different Pd reduction methodologies. The materials were prepared using sodium borohydride as a reducing agent and analyzed toward formate oxidation in alkaline media. The prepared electrocatalysts showed peaks of Pd face-centered cubic and TiO2 anatase and rutile phases and an average particle size between 3.7 and 7.9 nm. Experiments considering formate electro-oxidation (voltammetry and chronoamperometry) showed that the presence of TiO2 is favorably using both synthesis methodologies while single cells revealed Pd nanoparticles supported on physical mixtures of carbon and TiO2, in the proportion of 75:25 as the most efficient, which was explained by the carbon high electrical conductivity and small quantities of TiO2 working as co-catalyst.

Palavras-Chave: palladium; nanoparticles; titanium oxides; oxidation; formate fuel cells

GUIMARAES, VITORIA P.; NANDENHA, JULIO; ORZARI, LUIZ O.; FATIBELLO-FILHO, ORLANDO; OLIVEIRA NETO, ALMIR; JANEGITZ, BRUNO C.; VICENTINI, FERNANDO C.; ASSUMPCAO, MONICA H.M.T. Effect of TiO2 and synthesis strategies on formate oxidation: electrochemical and fuel cell approaches. Electrocatalysis, v. 14, n. 2, p. 221-231, 2023. DOI: 10.1007/s12678-022-00789-5. Disponível em: http://repositorio.ipen.br/handle/123456789/33980. Acesso em: $DATA.

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Abstract: L-Cysteine (Cys) is a non-essential sulfur-containing amino acid, crucial for protein synthesis, detoxification, and several metabolic functions. Cys is widely used in the agricultural, food, cosmetic, and pharmaceutical industries. So, a suitable sensitive and selective sensing approach is of great interest, and a low-cost sensor would be necessary. This article presents silver nanoparticles (EuAgNPs) synthesized by a green synthesis method using Eugenia uniflora L. extracts and photoreduction. The nanoparticles were characterized by UV/VIS, transmission electron microscopy, high-performance liquid chromatography (HPLC), FTIR, and Zeta potential. With the addition of Cys in the EuAgNPs solution, the terminal thiol part of L-cysteine binds on the surface of nanoparticles through Ag−S bond. The EuAgNPs and CysAgNPs coexist until flavonoids bound the amino group of Cys, enhancing the red color of solutions. The EuAgNPs provided selectivity to detect Cys among other amino acids, and its detection limit was found to be 3.8 nM. The sensor has the advantages of low-cost synthesis, fast response, high selectivity, and sensitivity.

Palavras-Chave: trees; cysteine; amino acids; silver; nanoparticles; photochemistry; reduction

LOPES, ISABELA S.; CASSAS, FERNANDO; VEIGA, THIAGO A.M.; SILVA, FLAVIA R. de O.; COURROL, LILIA C. Synthesis and characterization of Eugenia uniflora L. silver nanoparticles and L-cysteine sensor application. Chemistry and Biodiversity, v. 20, n. 1, p. 1-12, 2023. DOI: 10.1002/cbdv.202200787. Disponível em: http://repositorio.ipen.br/handle/123456789/33978. Acesso em: $DATA.

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Abstract: Arapaima gigas, known as Pirarucu in Brazil, is one of the largest freshwater fish in the world. Some individuals could reach 3 m in length and weight up to 200 kg. Due to extinction risks and its economic value, the species has been a focus for preservation and reproduction studies. Thyrotropin (TSH) is a glycoprotein hormone formed by 2 subunits α and β whose main activity is related to the synthesis of thyroid hormones (THs)—T3 and T4. In this work, we present a combination of bioinformatics tools to identify Arapaima gigas βTSH (ag-βTSH), modeling its molecular structure and express the recombinant heterodimer form in mammalian cells. Using the combination of computational biology, based on genome-related information, in silico molecular cloning and modeling led to confirm results of the ag-βTSH sequence by reverse transcriptase-polymerase chain reaction (RT-PCR) and transient expression in human embryonic kidney (HEK293F) cells. Molecular cloning of ag-βTSH retrieved 146 amino acids with a signal peptide of 21 amino acid residues and 6 disulfide bonds. The sequence has a similarity to 39 fish species, ranging between 43.1% and 81.6%, whose domains are extremely conserved, such as cystine knot motif and N-glycosylation site. The Arapaima gigas thyrotropin (ag-TSH) model, solved by AlphaFold, was used in molecular dynamics simulations with Scleropages formosus receptor, providing similar values of free energy ΔGbind and ΔGPMF in comparison with Homo sapiens model. The recombinant expression in HEK293F cells reached a yield of 25 mg/L, characterized via chromatographic and physical-chemical techniques. This work shows that other Arapaima gigas proteins could be studied in a similar way, using the combination of these techniques, recovering more information from its genome and improving the reproduction and preservation of this prehistoric fish.

Palavras-Chave: fishes; thyroid hormones; tsh; molecules; cloning; toxicity

FREIRE, RENAN P.; HERNANDEZ-GONZALEZ, JORGE E.; LIMA, ELIANA R.; SUZUKI, MIRIAM F.; OLIVEIRA, JOAO E. de; TORATI, LUCAS S.; BARTOLINI, PAOLO; SOARES, CARLOS R.J. Molecular cloning and AlphaFold modeling of thyrotropin (ag-TSH) from the Amazonian fish Pirarucu (Arapaima gigas). Bioinformatics and Biology Insights, v. 17, p. 1-13, 2023. DOI: 10.1177/11779322231154148. Disponível em: http://repositorio.ipen.br/handle/123456789/33976. Acesso em: $DATA.

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Abstract: The construction of a data bank concerning metal and metalloid content of bioindicator fish from coastal areas is very important as it can help environmental managers in decision making. In natural conditions, the concentration of elements can be influenced by abiotic parameters such as water salinity. In this study, catfish Cathorops spixii were evaluated concerning the total arsenic (As) concentration in the muscle tissues of individuals subjected to different abiotic conditions in the Cananéia-Iguape Estuarine-Lagoon Complex (CIELC), which was recently included on the Ramsar list of wetlands of international importance. Seventy-four catfish were seasonally caught in the northern and southern regions of the CIELC and their hydrochemical parameters were obtained. C. spixii from the southern, best preserved, area showed arsenic concentrations around ten times higher than the maximum limit established for fish intended for human consumption. However, these high concentrations of arsenic could be associated with the abiotic parameters of the water, such as salinity variations, in this area.

Palavras-Chave: fishes; arsenic; estuaries; environmental protection; salinity

AZEVEDO, JULIANA S.; BRAGA, ELISABETE S.; KUNIYOSHI, LEONARDO S.; FAVARO, DEBORAH I.T. Seasonal arsenic in catfish (Siluriformes, Ariidae) and the hydrochemical conditions of two areas in a Ramsar site on the Brazilian coast. Anais da Academia Brasileira de Ciências, v. 95, n. 2, p. 1-11, 2023. DOI: 10.1590/0001-3765202320210033. Disponível em: http://repositorio.ipen.br/handle/123456789/33974. Acesso em: $DATA.

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Abstract: In recent years, Brazil has intensified investments in nuclear innovation for peaceful purposes. Currently, in the country, there are six reactors in operation and three under construction. These reactors, at the end of their useful life, must be decommissioned, in a process that includes technical and administrative actions aimed at the partial or total removal of regulatory control, with a view of to the safety of the installation site, the health of employees, the public, and the protection of the environment. Thus, these activities involve risks that must be managed systematically, following the rules and guidelines established by responsible bodies. The International Atomic Energy Agency (IAEA) recently identified the need for practical guidelines for risk management in decommissioning projects and elaborated the publication “Management of Project Risks in Decommissioning” of the Safety Reports Series Nº 97. In Brazil, there is no experience in execution the decommissioning of nuclear reactors, thus, this work will present and analyze the main risks of nuclear reactor decommissioning projects in Brazil, using techniques from the risk assessment process of the ISO/IEC 31010 Standard, considering the wide international experience portrayed on the subject.

NETO, A.B.C. Risks to be considered in nuclear reactor decommissioning projects in Brazil. Brazilian Journal of Radiation Sciences, v. 10, n. 4, p. 1-24, 2022. DOI: 10.15392/2319-0612.2022.2111. Disponível em: http://repositorio.ipen.br/handle/123456789/33924. Acesso em: $DATA.

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Abstract: Nuclear energy divides public opinion with its “good” and “bad” applications. Almost immediately after the discovery of radiation, radioactive elements purified by the Curies were used in health treatments, but with the nuclear bombs of Hiroshima and Nagasaki, the subject was marked by bad public opinion, being related to death and destruction. Nowadays, nuclear physics is used in many important fields, such nuclear medicine for the diagnosis and treatment of various types of diseases, but the prejudice and lack of knowledge of the general public has not yet improved its “fame”. This work proposes to change a little of this paradigm. Through a questionnaire, the public perception of radioactivity was evaluated. The most important result obtained is that the public is interested in learning about radiation and nuclear energy and is willing to change their negative views.

FONTOLAN, A.F.A.M.; SOUZA, C.D. de. Assessment of public perception of radioactivity in Brazil. Brazilian Journal of Radiation Sciences, v. 10, n. 4, p. 1-19, 2022. DOI: 10.15392/2319-0612.2022.2095. Disponível em: http://repositorio.ipen.br/handle/123456789/33922. Acesso em: $DATA.

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Abstract: This paper aims to discuss the convenience and feasibility of increasing the nuclear energy participation on the Brazilian energy mix, amid a national context of climate change, scarcity of natural resources necessary to baseload energy generation, particularly hydropower, discussions on a possible restart and expansion of Brazilian nuclear program, whilst the population still suffers socioeconomic impacts resulting from COVID-19 pandemic as well as the pre-pandemic economic crisis. The work proposes four analysis axes: environmental factors, economic, safety/legislation and technological aspects, and through bibliographic research in scientific articles published in journals, theses, dissertations, laws, regulations and international recommendations, it was possible, as a result of the research, to draw an optimistic overview of a possible future expansion of the Brazilian nuclear program, considering the advantages and challenges of using the nuclear alternative when compared to other energy sources.

FERRARI, L.A.; AYOUB, J.M.S.; TAVARES, R.L.A.; SILVA, A.L.C.; SENEDA, J.A. Must nuclear energy be increased on Brazilian energy mix in a Post-COVID-19 world?. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-20, 2022. DOI: 10.15392/2319-0612.2022.1920. Disponível em: http://repositorio.ipen.br/handle/123456789/33920. Acesso em: $DATA.

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Abstract: Since the Fukushima Daiichi accident, external events analysis has become a priority issue within regulatory bodies, operators, and designers, raising concerns about the capabilities of nuclear power plants to withstand severe conditions. Generally, the methodology applied to the Probabilistic Safety Assessment (PSA) of external events consists of the identification of potential single and combined external hazards, screening of external hazards, analysis of site and plant response, analysis of initiating events and quantification of accident sequences probabilities. Therefore, in this paper, the requirements and other information on new nuclear installations projects necessary to implement a comprehensive PSA of external events throughout plant lifetime are evaluated. In addition, it is necessary to clearly identify all the resources that must be available to continuously expand PSA scope to include all types of initiating events, levels of analysis and plant operation modes.

SILVA, T.P.; MATURANA, M.C.; OLIVEIRA, P.S.P. de; MATTAR NETO, M. External Events PSA: requirements applicable to new nuclear installations projects after Fukushima Daiichi accident. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-8, 2022. DOI: 10.15392/2319-0612.2022.1977. Disponível em: http://repositorio.ipen.br/handle/123456789/33918. Acesso em: $DATA.

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Abstract: Pseudoboehmite is an aluminium compound with a structure similar to that of boehmite. The unit cell of the pseudoboehmite is slightly larger than that of the boehmite because of the greater incorporation of water in the same structure [1]. It has particles of nanometric dimensions and can be synthesized with extremely high purity. Several papers published in the literature show the potential of using this material in the controlled release of drugs, including cancer treatment [2,3]. Using drugs in complexes incorporated into polymer matrices and ceramic gels can lead to adequate control of gastrointestinal absorption when administered orally. Consequently, there is the possibility of promoting a gradual action through the progressive release of the drug, thus increasing its efficiency and reducing dose and toxicity. Previous studies have shown that pseudoboehmite is non-toxic and can be used for drug delivery. During the tests to determine the toxicity of this material, it was observed that the blood glucose content was reduced in mice that took pseudoboehmite by gavage. Since pseudoboehmite is obtained via low-cost inorganic synthesis, different physicochemical characteristics can be incorporated into this high purity medium. The formed structure was evaluated as a drug delivery system to establish a profile of the influence of the physicochemical properties of a molecule in the process of interaction with pseudoboehmite, a drug with recognized pharmacological activity, simvastatin (IUPAC name (1S,3R,7S,8S,8aR)-8-{2-[(2R,4R)-4-hydroxy-6-oxooxan-2-yl]ethyl}-3,7-dimethyl-1,2,3,7,8,8a-hexahydronaphthalen-1-yl 2,2-dimethylbutanoate) was choose. It also emphasizes the importance of pseudoboehmite as a drug carrier, serving as a precursor to new therapeutic systems. The synthesis of pseudoboehmite from ammonium hydroxide and aluminium nitrate was optimized to release simvastatin in vitro. After absorption and hydrolysis in the liver to form the active β-hydroxy acid metabolite, simvastatin acts as a potent reversible, competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, an early and rate-limiting enzyme in the biosynthesis of cholesterol.

VICENTE, MARCOS A.A.H.; SILVA, LEONARDO G.A.; LIMA, NELSON B.; OLIVEIRA, RENE R.; BERNUSSI, AYRTON; SARMENTO, BRUNO; BARBOSA, ISABELLA T.F.; MUNHOZ JUNIOR, ANTONIO H. Synthesis of pseudoboehmite nanoparticles and use in simvastatin drug delivery. Defect and Diffusion Forum, v. 420, p. 141-151, 2022. DOI: 10.4028/p-04240m. Disponível em: http://repositorio.ipen.br/handle/123456789/33887. Acesso em: $DATA.

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Abstract: The present work aimed at the development of Pt-TiO2/SiO2 materials applied to the degradation of a pharmaceutical pollutant in a fixed-bed microreactor in continuous mode. First, a wide investigation of the optimal platinum content in TiO2/SiO2 was carried out based on extensive characterization through XRD, DRS, SEM, TEM, and XPS techniques. For the content range studied, no significant changes were observed in the crystallinity of the material, with peaks related to the anatase phase and PtO2 in the diffractograms. SEM images combined with EDS spectra indicated the presence of platinum and a large heterogeneity in the particles. MET analyses showed PtO2 nanoparticles in close contact with TiO2, allowing the formation of a type II heterojunction. XPS showed platinum in the 0 and +4 oxidation states, suggesting that platinum metal and PtO2 are both present. Regarding the degradation experiments, the optimal catalyst achieved 81% degradation of acetaminophen for a residence time of 1 h, while the catalyst without platinum reached only 27% degradation. The catalyst activity dropped from 81 to 57% in 2 h and remained stable for six reuse cycles. Increasing the inlet flow rate and concentration reduced the pollutant degradation although there was an increase in the reaction rate. Finally, a photocatalytic mechanism was proposed in which a type II heterojunction was developed, with generation of hydroxyl radicals by the positive holes in the VB of TiO2 as well as superoxide radicals by the electrons in the CB of PtO2.

GUSMAO, CAROLINA de A.; BORGES, LAURA T.; PALHARIM, PRISCILA H.; OTUBO, LARISSA; RODRIGUES, ORLANDO; GOUVEA, DOUGLAS; RAMOS, BRUNO; TEIXEIRA, ANTONIO C.S.C. Synthesis, characterization, and application of Pt/PtO2-TiO2/SiO2 materials on a continuous flow packed bed microreactor for enhanced photocatalytic activity under sunlight. Water, v. 14, n. 23, p. 1-18, 2022. DOI: 10.3390/w14233864. Disponível em: http://repositorio.ipen.br/handle/123456789/33885. Acesso em: $DATA.

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Abstract: A técnica de marcação permite estudar os comportamentos e interações ecológicas dos insetos, como por exemplo padrões de dispersão, movimento, territorialidade, manuseio, consumo de alimentos, associações vetor-parasita, e cadeias ou teias alimentares. Essa revisão descreve as vantagens e desvantagens dos marcadores, destacando três métodos cujo diferencial é a permanência no inseto independente do estágio de vida. Os radioisótopos minimizam a manipulação direta e o trauma nos insetos, podem ser aplicados em grandes populações e são facilmente rastreáveis, porém o seu descarte limita a aplicação em campo. Os isótopos estáveis ocorrem naturalmente no ambiente, não são radioativos e estão relacionados à estudos ecológicos de níveis tróficos e processos metabólicos, dentre os elementos mais são utilizados, os isótopos de carbono refletem principalmente a dieta dos animais; os isótopos de nitrogênio refletem as práticas agrícolas (extensiva x intensiva) e em parte a dieta. Os isótopos de oxigênio e hidrogênio são vinculados à composição isotópica da água que, por sua vez, é dependente de fatores geográficos tais como altitude, clima e latitude. Por sua vez, os oligoelementos também são utilizados como marcadores internos (não radioativos) e podem variar de acordo com a localização geográfica alterando as quantidades encontradas nas plantas e insetos. Portanto, a busca de uma melhor metodologia que permita detectar a correlação dos insetos com o homem e o meio ambiente depende do tipo de estudo a ser realizado.

ARAUJO, MARCIO M. de; SALAS, FERNANDO J.S.; ARTHUR, VALTER. Marcação de insetos para estudos biológicos. Revista de la Facultad de Agronomía, v. 121, n. 1, p. 1-14, 2022. DOI: 10.24215/16699513e093. Disponível em: http://repositorio.ipen.br/handle/123456789/33883. Acesso em: $DATA.

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Abstract: Em Radioterapia Guiada por Imagem (IGRT), é comum a aquisição de diversas imagens de um paciente e, por consequência, a realização de registro de imagem para a comparação entre elas. Devido a isso, é fundamental que sejam realizados tanto um bom registro quanto um bom controle da qualidade (CQ) do registro. O objetivo deste trabalho é avaliar um registro de imagem quando realizado com e sem pontos de referência. Para isso, imagens de Tomografia Computadorizada (TC) de um paciente da radioterapia foram utilizadas para realizar registros rígido e elástico, com e sem pontos de referência. A técnica Scale Invariant Feature Transform (SIFT) foi utilizada para desenvolver um algoritmo para a extração semiautomática de pontos-chave estáveis das imagens, tanto para os registros quanto para a avaliação de tais registros. Através dos valores de erro médio, erro máximo e Informação Mútua (IM) encontrados, foi possível verificar um melhor alinhamento das imagens quando realizado o registro partindo inicialmente dos pontos de referência extraídos, em comparação com o alinhamento realizado sem esses pontos de referência. A SIFT mostrou ser uma ótima ferramenta para realizar ambas as tarefas e, quando possível, o profissional da clínica deve realizar um bom CQ quantitativo de registro, considerando pontos de referência distribuídos pelas imagens.

MAZER, AMANDA C.; YORIYAZ, HELIO. Avaliação de registro de imagem realizado com e sem pontos de referência extraídos através da técnica SIFT. Revista Brasileira de Física Médica, v. 16, p. 1-8, 2022. DOI: 10.29384/rbfm.2022.v16.19849001676. Disponível em: http://repositorio.ipen.br/handle/123456789/33881. Acesso em: $DATA.

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Abstract: Yttria-stabilized tetragonal zirconia (Y-TZP) ceramics have excellent mechanical properties. However, such materials cannot undergo plastic deformation at room temperature due to their high hardness and brittleness values, hindering machinability. To overcome these limitations, we propose a zirconia-yttria-titania ceramics, based on zirconia containing 3mol% yttria and up to 15mol% titania. The zirconia-yttria-titania powders were synthesized by co-precipitation method, uniaxially pressed and sintered at 1400°C/5 h. Sample characterizations were carried out by X-ray diffraction, scanning electron microscopy and mechanical properties through Vickers hardness and toughness measurements. Compared to the Y-TZP ceramics, the yttria stabilised tetragonal zirconia ceramics co-doped with 10mol%Ti showed noticeable increase of tetragonality parameter, higher toughness and lower hardness values, indicating plasticity at room temperature. Furthermore, the atomistic simulation by Density Functional Theory methodology suggests the occurrence of spatial arrangement of the atoms, explaining the proposed plasticity.

USSUI, VALTER; LAZAR, DOLORES R.R.; LIMA, NELSON B. de; ARATA, ANELYSE; RIBEIRO, FABIO N.; DALPIAN, GUSTAVO M.; MARCHI, JULIANA; PASCHOAL, JOSE O.A. Room temperature plasticity of zirconia-yttria-titania ceramics: experimental indications and structural modelling. Processing and Application of Ceramics, v. 16, n. 4, p. 367-373, 2022. DOI: 10.2298/PAC2204367U. Disponível em: http://repositorio.ipen.br/handle/123456789/33879. Acesso em: $DATA.

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Abstract: Quasielastic scattering angular distributions of radioactive (8Li, 7,10Be, and 8,12B) and stable (6,7Li, 9Be, and 11B) projectiles on a 9Be target are presented. The angular distributions have been analyzed by the optical model using Woods-Saxon form factor and São Paulo potential. Total reaction cross sections have been obtained from the optical model analysis and a comparison between different systems is presented. Coupled channels (CC), coupled reaction channels (CRC), and continuum-discretized coupled channels (CDCC) calculations have been performed to investigate the effect of the cluster configuration in the projectile inelastic excitation, breakup, and stripping reactions on the quasielastic angular distributions.

UMBELINO, U.; LICHTENTHALER, R.; SANTOS, O.C.B.; PIRES, K.C.C.; SERRA, A.S.; SCARDUELLI, V.; LARA, A.L. de; ZEVALLOS, E.O.N.; ZAMORA, J.C.; LEPINE-SZILY, A.; SHORTO, J.M.B.; ASSUNCAO, M.; ZAGATTO, V.A.B. Quasielastic scattering of light radioactive and stable projectiles on 9Be. Physical Review C, v. 106, n. 5, p. 054602-1 - 054602-15, 2022. DOI: 10.1103/PhysRevC.106.054602. Disponível em: http://repositorio.ipen.br/handle/123456789/33877. Acesso em: $DATA.

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Abstract: Maraging steels are precipitation hardening alloys that can achieve an ultra-high yield strength (~3 GPa), however associated with low toughness. During exposure to high temperatures, an oxidation process occurs on the surface of these steels, generally, the oxides formed are hematite and/or magnetite. The aim of this study was to investigate oxidation on a maraging 13Ni15Co10Mo at annealing temperature of 900 °C. The bulk microstructure was investigated by several complementary techniques and the oxidized surface was characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). The results showed that the bulk microstructure, at annealed condition, consists of a lath martensite with a hardness of round 400 HV. The most external and oxidized surface contains the oxides hematite, magnetite and kamiokite. Finally, the presence of austenite was detected in the first 2 μm below the surface. Chemical microanalysis indicated that the austenite is stable at room temperature in this region due a composition gradient that makes this region rich in nickel and cobalt. The composition gradient is due atom diffusion during oxides formation. Austenite near to the surface is very convenient as it could avoid crack initiation and propagation, improving toughness.

FONSECA, DANIELA P.M. da; CARVALHO, LEANDRO G. de; LIMA, NELSON B. de; PADILHA, ANGELO F. Austenite formation in the oxidized layer of ultra-high-strength 13Ni15Co10Mo maraging steel. Metals, v. 12, n. 12, p. 1-10, 2022. DOI: 10.3390/met12122115. Disponível em: http://repositorio.ipen.br/handle/123456789/33875. Acesso em: $DATA.

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Abstract: This study evaluated the essential and non-essential elements in lettuce cultivated on a rooftop urban garden in the metropolitan region of São Paulo. In addition, the human health risks associated with the potentially toxic metals based on the estimated daily intake (EDI), the target hazard quotient (THQ), and the possible sources of heavy metal contamination by multivariate statistical were analyzed. The lettuces contain essential macronutrients such as K, Ca, and Mg. The Cd, Cu, and Pb concentrations did not exceed the Brazilian legislation limit. Ba, Ni, Cr, Co, and Pb presented low levels compared to oral reference dose and they may be associated to vehicles emissions. Both EDI and THQ values suggested minimal risk upon consumption of lettuce.

SUSSA, FÁBIO V.; FURLAN, MARCOS R.; VICTORINO, MARCOS; FIGUEIRA, RUBENS C.L.; SILVA, PAULO S.C. Essential and non‑essential elements in lettuce produced on a rooftop urban garden in São Paulo metropolitan region (Brazil) and assessment of human health risks. Journal of Radioanalytical and Nuclear Chemistry, v. 331, n. 12, p. 5869-5879, 2022. DOI: 10.1007/s10967-022-08661-y. Disponível em: http://repositorio.ipen.br/handle/123456789/33873. Acesso em: $DATA.

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Abstract: In this research we decided to analyze the addition of silver (Ag°) on zinc oxide (ZnO) utilizing two nanoparticles: the synthesized zinc oxide-doped-silver nanoparticles (ZnO/Ag_Lab) utilizing the zinc nitrate as metal precursor for ZnO and silver nitrate as metal precursor for Ag°; and the commercial nanoparticle ZnO/Ag. For the study of application of the nanoparticles, they were processed in the form of films and the polymer utilized was the blend of HMSPP (high melt strength polypropylene) and styrene-ethylene/butadiene-styrene. For the study of nanoparticles, they were submitted to biocide tests against Staphylococcus aureus (ATCC 6538) and Escherichia coli (ATCC8739) and XRD (X-Ray Diffraction). The XRD analysis results indicated, in both of nanoparticles, with the presence of wurtzite phase of ZnO, being that on the commercial nanoparticles the intensity of peak was higher than that of synthesized one, on other hand, the peaks attributed to Ag°, were more intense in the synthesized nanoparticle.

KOMATSU, LUIZ G.H.; CAJADO, GIUSEPPE M.; PARRA, DUCLERC F. Effects of silver addition in zinc oxide nanoparticles on films of HMSPP/SEBS against Staphylococcus aureus and Escherichia coli contamination. Journal of Materials Science and Engineering B, v. 12, n. 7-9, p. 108-116, 2022. DOI: 10.17265/2161-6221/2022.7-9.004. Disponível em: http://repositorio.ipen.br/handle/123456789/33871. Acesso em: $DATA.

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Abstract: The mechanisms of action of photobiomodulation (PBM) in oral mucositis (OM) are not completely elucidated. To enlighten the role of PBM in the evolution of epithelial maturity in OM ulcers, the present study evaluated the effect of PBM with red ( ) wavelength of 660 nanometers (nm) and infrared of 780 nm in radio-induced OM wounds on the tongue of rats, eight and twenty days after irradiation with single dose of 20 Gy. The percentage area corresponding to positive staining for cytokeratin 10 (CK10) and 14 (CK14) proteins was evaluated in the epithelial area of the lesions, using an immunohistochemical technique (IHC), 8 and 20 days after the induction of lesions, and compared with an untreated control group. CK10 was significantly more expressed in the group treated with 660 nm PBM. CK14 did not show quantitative differences between the groups evaluated. However, whereas in the groups treated with PBM, CK14 was already restricted to the basal layer of the epithelium, as expected in healthy epithelia, in control group it was also expressed in upper layers of the epithelium. In this work, PBM was able to improve epithelial maturity of the repaired OM wound, especially in the 660 nm group.

SARDO, ARIANE V.N.; ANDRADE, MAIRA F.; FIGUEIREDO, ANAELIZA; ROSIN, FLAVIA C.P.; CORREA, LUCIANA; ZEZELL, DENISE M. Does photobiomodulation affects CK10 and CK14 in oral mucositis radioinduced repair?. International Journal of Molecular Sciences, v. 23, n. 24, p. 1-9, 2022. DOI: 10.3390/ijms232415611. Disponível em: http://repositorio.ipen.br/handle/123456789/33868. Acesso em: $DATA.

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Abstract: Heterogeneous photocatalysis is an important and promising alternative for efficient water and wastewater treatment processes. The synthesis of composite materials has attracted attention due to their improved photocatalytic activity and stability. In the present work, composites made of WO3-AgCl were synthesized by a simple one-step hydrothermal method. The evaluation of the effects of reaction temperature and synthesis time for this composite is reported for the first time. The materials were characterized by XRD, SEM, TEM, EDS, BET, UV–vis DRS, XPS, EPR and PL. All photocatalysts showed broad-spectrum activity due to their strong absorption in the UV region and some absorption in the visible region. The morphology of the materials was highly influenced by the synthesis temperature and time, which affected the photocatalytic efficiency. All materials exhibited good photocatalytic activity under simulated sunlight, with maximum acetaminophen removal of 99.6% for the catalyst synthesized at 120 °C and 12 h. Stability tests showed considerable stability after four cycles. The main reactive species participating in the photodegradation reaction were found to be O2•-> h+ ∼ •OH. The heterojunction formed between AgCl and WO3 plays an important role in the photocatalytic activity, especially when the AgCl surface is not completely covered by WO3.

PALHARIM, PRISCILA H.; CAIRA, MARIA C.D.A.; GUSMAO, CAROLINA de A.; RAMOS, BRUNO; SANTOS, GABRIEL T. dos; RODRIGUES JUNIOR, ORLANDO; TEIXEIRA, ANTONIO C.S.C. Effect of temperature and time on the hydrothermal synthesis of WO3-AgCl photocatalysts regarding photocatalytic activity. Chemical Engineering Research and Design, v. 188, p. 935-953, 2022. DOI: 10.1016/j.cherd.2022.10.045. Disponível em: http://repositorio.ipen.br/handle/123456789/33865. Acesso em: $DATA.

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Abstract: Environment contamination is a widespread problem in all countries around the world. Contaminated sites are consequence of land use and occupation without environmental concerns, and it can cause contamination of superficial soil, subsoil, and groundwater. This issue affects urban planning, human health as well natural resource availability. The management of contaminated land data and its communication to stakeholders is a significant driver to achieve sustainable urban planning, promoting equally sustainable cities and communities. Therefore, tools to improve comprehension of environmental quality of cities is essential to face this challenge. Here, we develop an environmental indicator to analyze contaminated land data and communicate its complexity to non-technical stakeholders. The indicator developed, adopts 15 variables and considering three parameters: polluting substance concentration, affected environmental matrices, and the environmental behavior of the polluting substance. A dataset has been elaborated containing information about 25 contaminated sites of Lapa District, the pilot area of São Paulo city, and the environmental indicator was applied, resulting in four environmental contamination levels: low, moderate, high, and remarkably high degrees, existing in an individually site.

Palavras-Chave: environment; sustainable development; land use; land pollution; planning; pollution control

LINO, JULIANA dos S.; ANDRADE, DELVONEI A. de. Improving contaminated land data communication through the developing of an environmental indicator. Brazilian Journal of Development, v. 8, n. 12, p. 78628-78645, 2022. DOI: 10.34117/bjdv8n12-120. Disponível em: http://repositorio.ipen.br/handle/123456789/33861. Acesso em: $DATA.

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Abstract: Females of Rhipicephalus (Boophilus) microplus ticks ingurgitated and in the prepost phase were submitted to doses of 0, 5, 10, 15, 20 and 25 Gy of Cobalt-60 with the aim of evaluating their effects on ovarian morphohistology with consequent establishment of the degree of damage caused to the reproductive organs of this species. For this purpose, 24 hours after exposure to Co-60 (142 Gy/h) the ectoparasites were dissected and had their ovaries removed and prepared for histology with haematoxylin and eosin staining. The results obtained showed that the 5 Gy dose radiation had a morphological aspect similar to the control standard adopted. The histological sections related to doses of 10 and 15 Gy did not cause many changes in the ovaries, except that changes were observed in the calf granules (size, distribution and staining pattern), as well as the extensive presence of cytoplasmic vacuoles in the ovocytes, especially in the region that makes contact with the ovocyte/pedicel, suggesting the occurrence of changes also in the physiology of the organ. In the ovaries exposed to doses of 20 and 25 Gy, severe alterations were observed in the organ as a whole, as well as in the germ cells (oocytes) which suffered alterations in size and shape, distribution of calf granules, involvement of the DNA present in the germinal vesicle (oocyte nuclei), besides the extensive cytoplasmic vacuolization, alterations which made the maturation of these cells impossible and consequently inhibited the production of new individuals.

Palavras-Chave: insects; ticks; histology; animal tissues; cobalt 60; ovaries; ionizing radiations; histological techniques

PASQUALINI, ALEXANDRE A.; ARTHUR, VALTER; SCHIAVOLIN, MICHELEN B.; ABREU, MARINA R. de; CAMARGO-MATHIAS, MARIA I. Histological evaluation of Rhipicephalus (Boophilus) microplus tick ovaries subjected to cobalt-60 ionizing radiation. Applied Veterinary Research, v. 1, n. 2, p. 1-7, 2022. DOI: 10.31893/avr.2022007. Disponível em: http://repositorio.ipen.br/handle/123456789/33859. Acesso em: $DATA.

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Abstract: Este trabalho teve como objetivo determinar a dose letal imediata de radiação gama do Cobalto-60 (60Co) para Acanthocelides obtectus, Zabrotes subfasciatus e Callosobruchus maculatus utilizando o irradiador multipropósito IPEN/CNEN. Os insetos foram mantidos em grãos de feijão das variedades Phaseolus vulgaris e Vigna unguiculata acondicionados em potes plásticos. Utilizando-se o delineamento experimental inteiramente casualizado, foram selecionados 20 indivíduos adultos com idade entre 3–7 dias, para cada repetição, num total de 5 repetições por tratamento. Foram aplicadas doses crescentes de radiação gama até atingir a mortalidade total dos insetos. A dose de 3,0 kGy foi estabelecida para controle imediato dos insetos adultos das espécies estudadas.

Palavras-Chave: food processing; irradiation; insects; pest control; cobalt 60; gamma radiation; radiation doses

REIS, FABRICIO C.; ARAUJO, MARCIO M. de; ROMANO, JAMILE I.S.; POTENZA, MARCOS R.; ARTHUR, VALTER. Dose letal imediata de radiação gama para espécies de carunchos do feijão utilizando irradiador multipropósito. Agrarian, v. 15, n. 55, 2022. DOI: 10.30612/agrarian.v15i55.15712. Disponível em: http://repositorio.ipen.br/handle/123456789/33857. Acesso em: $DATA.

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Abstract: A mama é composta por tecido adiposo, tecido fibroso de sustentação e tecido glandular associados a vasos sanguíneos, linfáticos e nervos. Um fator de risco para o surgimento do câncer de mama é o aumento na densidade mamográfica no tecido mamário, a densidade mamográfica corresponde à quantidade de tecido fibroglandular nas mamas, apresentando-se como um tecido radiopaco, e possui quatro classificações, segundo o Breast Imaging Reporting and Data System (BI-RADS). Mulheres com mamas densas apresentam um risco de quatro a seis vezes maior de desenvolver carcinogênese. O carcinoma de mama pode ser dividido conforme sua localização em in situ ou infiltrativo e a mamografia é o exame mais comum na detecção de câncer de mama. Esta revisão tem o objetivo de investigar os fatores que modulam a densidade mamográfica, e como esses fatores se relacionam com o aumento de mamas densas. A pesquisa bibliográfica foi realizada pelo PubMed - NCBI num período de nove anos em inglês, utilizando como palavras-chaves “densidade mamográfica”, “câncer de mama” e “ mamografia”. Alguns fatores podem influenciar na densidade mamográfica como por exemplo herdabilidade, raça e etnia, dieta, terapias de reposição hormonal, ingestão de álcool, estilo de vida, fatores reprodutivos e hormonais - como menopausa, paridade, idade ao primeiro nascimento e idade da menarca - tamanho corporal, microcalcificações e faixa etária. O câncer de mama também é menos incidente em mulheres afro-americanas e indígenas, isso pode ser explicado pelos hábitos de vida dessa população, por exemplo: primeira gravidez mais cedo, multiparidade, amamentação prolongada e ausência de terapias hormonais. Fatores considerados de variável categórica e contínua, como ingestão de álcool, tabagismo e atividade física ainda não estão bem estabelecidas suas relações com o aumento ou diminuição da densidade mamográfica, o que requer mais estudos para chegar a resultados conclusivos. A mamografia ainda é a forma mais comum do rastreamento de câncer de mama, porém sua sensibilidade é menor quando se trata de mamas densas, por conta disso estão sendo utilizados e desenvolvidos novos métodos de diagnóstico por imagem como: ressonância magnética, ultrassonografia, tomossíntese digital da mama e a ultrassonografia automatizada das mamas (ABUS). Essa revisão literária traz estudos detalhados que visam compreender os fatores que levam ao aumento da densidade mamográfica, permitindo o melhor diagnóstico e mapeamento de grupos de risco, o que possibilita amenizar as consequências dessas modificações, a fim de fornecer medidas preventivas contra o câncer de mama.

Palavras-Chave: mammary glands; density; neoplams; carcinomas; biomedical radiography; health hazards; diagnosis

SOARES, NAYANI G. de L.; GUSHIKEN, KAROLINA Y.; FREITAS, GUSTAVO R.; JOAQUIM, ARIANE, A.M.; RODRIGUES, GUILHERME O. Fatores influentes na densidade mamográfica e seu impacto no Câncer de mama. Brazilian Journal of Health Review, v. 6, n. 1, p. 1222-1238, 2023. DOI: 10.34119/bjhrv6n1-093. Disponível em: http://repositorio.ipen.br/handle/123456789/33696. Acesso em: $DATA.

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Abstract: Introduction: This work aims to assess if the anode position during chest radiography of pediatric patients with heart congenital disease (HCD) influences medical image results. The approach is to reverse the orientation of the x-ray tube, with the anode end directed towards the patient's face (anode-heel effect). Methods: Five specialists analyzed 48 images, 24 from the control group (CG) and 24 with the anode end directed towards the patients' face (experimental group, EC). An ionization chamber was used to assess radiation dose received by sensitive organs. Results: The specialists considered both CG and EC images acceptable. But, the EC group's dose evaluation revealed that the thyroid received 12% less radiation and the gonads presented a 5.9% reduction. Based on the results, a new protocol was developed. Discussion/conclusion: The standardization of radiographic imaging procedures will reduce acquisition errors, resulting in adequate images in pediatric patients with HCD with less radiation dose, thus increasing patient safety and extending the life of the equipment.

Palavras-Chave: safety; patients; pediatrics; recommendations; radiation doses; x-ray equipment; biomedical radiography; anodes; radiation absorption analysis

SOUZA, CARLA D. de; FREITAS, GUSTAVO R.; MEDEIROS, ROGERIO F.; RAMALHO, ERCILIA; RODRIGUES, SERGIO C.; RODRIGUES, GUILHERME O. Protocol for reducing radiation exposure during pediatricthoracic radiography. Journal of Medical Imaging and Radiation Sciences, v. 53, n. 3, p. 437-443, 2022. DOI: 10.1016/j.jmir.2022.05.012. Disponível em: http://repositorio.ipen.br/handle/123456789/33678. Acesso em: $DATA.

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Abstract: To overcome the disadvantages generated by the lack of interfacial bonding between hydroxyapatite nanocrystals (HAPN) and agglomeration of particles in the development of biodegradable nanocomposites a chemical grafting method was applied to modify the surface of HAPN through grafting of the three-arms star-shaped poly(ε-caprolactone) (SPCL) onto the nanoparticles. The chemical grafting of SPCL onto HAPN (SPCL-g-HAPN) has been investigated using Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy (TEM), photoelectron spectroscopy, X-ray diffraction, zeta potential (ZP) and contact angle (CA). TEM micrographs of the SPCL-g-HAPN revealed the existence of hybrid organic/inorganic (O/I) nanoscale domains. The results of albumin (HSA) and fibrinogen (HFb) adsorption indicate resistance to HFb adsorption by SPCL-g-HAPN relatively to unmodified HAPN. The ZP and CA measurement suggest a heterogeneous topology for SPCL-g-HAPN likely due to the existence of hydrophobic-hydrophilic regions on the nanocomposite surface. The enzyme degradation by cholesterol esterase and lipase indicates that the rates of hydrolysis for SPCL-g-HAPN were very slow relative to the SPCL/HAPN blends. The in vitro biological studies showed that the human osteoblast-like cells (MG-63) cells had normal morphology and they were able to attach and spread out on SPCL-g-HAPN surfaces. A higher overall cellular proliferation was observed on SPCL-g-HAPN scaffolds compared to pure HAPN or SPCL materials.

Palavras-Chave: organic polymers; nanocrystals; hydroxy compounds; biodegradation; nanocomposites; apatites; protein; adsorption

KAIRALLA, ELENI C.; BRESSIANI, JOSE C.; BRESSIANI, ANA H. de A.; RIBELA, MARIA T. de C.P.; HIGA, OLGA Z.; QUEIROZ, ÁLVARO A.A. de. Physicochemical and biological properties of nanohydroxyapatite grafted with star-shaped poly(ε-caprolactone). Journal of Biomaterials Science, Polymer Edition, v. 33, n. 18, p. 2353-2384, 2022. DOI: 10.1080/09205063.2022.2104599. Disponível em: http://repositorio.ipen.br/handle/123456789/33655. Acesso em: $DATA.

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Abstract: Phytoextraction of rare earth elements (REE) from contaminated soils has gained importance during the last few decades. The Poços de Caldas municipality in Brazil is known for its mineral richness, including large reserves of REE. In this study, we report light REE (La, Ce, Sm, Pr, and Nd) in soils and plants collected in an area. Composite soil samples and plant individuals were collected, and total concentrations of LREE in soils were determined by wavelength dispersive X-ray fluorescence (WDXRF). The plant available LREE concentrations in soils were estimated upon the acetic acid method (F1 fractions) of the stepwise sequential extraction procedure, together with plant content that was analysed by inductively coupled plasma mass spectrometry (ICP-MS). The total sum concentrations of tested LREE in soils varied from 5.6 up to 37.9 g kg−1, the bioavailable fraction was ca. 1%, and a linear relationship was found between them. The only exception was Sm, whose availability was lesser and did not show a linear relationship. The concentration of LREE in non-accumulator plants varied from 1.3–950 mg kg−1 for Ce, La 1.1–99 mg kg−1, Sm 0.04–9.31 mg kg−1, Pr 0.1–24.1 mg kg−1, and Nd 0.55–81 mg kg−1. The concentration of LREE among shoots did not show a linear relation either with the available fraction or total content. The screening also revealed Christella dentata (Forssk.) Brownsey & Jermy, Thelypteridaceae family, as a promising hyperaccumulator species. The concentrations of LREE among shoots of six individuals of this species were in the ranges from 115 to 1872 mg kg−1 for Ce, La 190–703 mg kg−1, Sm 9–48 mg kg−1, Pr 32–144 mg kg−1, and Nd 105–478 mg kg−1.

Palavras-Chave: rare earths; soils; acetic acid; plants; contamination

ASHRAF, NERMEEN; RODRIGUES, EDUARDO S.; ALMEIDA, EDUARDO de; MONTANHA, GABRIEL S.; ABREU-JUNIOR, CASSIO H.; VITOVA, MILADA; GARCIA, RAFAEL H.L.; KUPPER, HENDRIK; CARVALHO, HUDSON W.P. de. Identification of potential plant species hyperaccumulating light rare earth elements (LREE) in a mining area in Minas Gerais, Brazil. Environmental Science and Pollution Research, v. 29, n. 60, p. 90779-90790, 2022. DOI: 10.1007/s11356-022-22009-9. Disponível em: http://repositorio.ipen.br/handle/123456789/33581. Acesso em: $DATA.

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Abstract: Objectives: The primary aim of this ex vivo study was to evaluate thermal damage and cutting efficiency of micro and super pulsed diode lasers. The secondary aim was to suggest a guideline to perform simple surgical excisions adequate for histopathological evaluation. Material and Methods: Ten groups of 10 specimens of pig tongues were excised using a blade (G1), a micro pulsed (G2–G9), and a super pulsed diode (G10) lasers. Different output power, pulse duration, pulse interval, and duty cycle were tested. Quantitative measures of thermal damage and excision times were recorded. Statistical analysis was performed at a significance level of 5%. Results: The control group (G1) presented no thermal damage. Within the laser groups (G2–G10), no statistically significant differences in depth of thermal damage (μm) were noted. G3 showed significantly less area of thermal damage (mm2) when compared with G7 and G9 (p < .05). The median excision time of the control group and super pulsed diode laser group were significantly lower (p < .001) than the micro pulsed diode laser groups. Conclusions: The cutting efficiency of the super pulsed diode laser is comparable to traditional blade, and with appropriate parameters, these lasers can produce predictable surgical outcomes with less collateral damage.

Palavras-Chave: diode-pumped solid state lasers; pulse techniques; animal tissues; oral cavity; damage; diagnostic techniques; biopsy; temperature dependence; depth dose distributions; depth dose distributions; optical depth curve; histological techniques

PRADO, MARILIZA C.O.; NWIZU, NGOZI N.; PATEL, SHALIZEH A.; STRECKFUS, CHARLES F.; ZEZELL, DENISE M.; BARROS, JULIANA. Thermal damage and excision time of micro and super pulsed diode lasers: a comparative ex vivo analysis. Clinical and Experimental Dental Research, v. 8, n. 6, p. 1655-1663, 2022. DOI: 10.1002/cre2.670. Disponível em: http://repositorio.ipen.br/handle/123456789/33579. Acesso em: $DATA.

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Abstract: Objective: To compare optical, morphological, chemical, and physical aspects of the sound enamel and white spot lesions (WSL) classified as ICDAS 2. Material and Methods: Seventeen human molars with one surface presenting WSL and a sound surface (2 x 2 mm window) were characterized by Quantitative light-induced fluorescence (QLF®), Optical coherence tomography (OCT), microhardness, and Raman spectroscopy. The ANOVA and Tukey’s test were used at 5% significance level. Results: The QLF comparison between distinct substrates yielded decreased ΔQ (integrated fluorescence loss) of -15,37%mm2 and -11,68% ΔF (fluorescence loss) for WSL. The OCT detected mean lesion depth of 174,43 μm. ANOVA could not detect differences in the optical attenuation coefficient between the substrates (p>0.05). Lower microhardness measures were observed in WSL than on sound enamel (p<0.05). The Raman spectra showed four vibrational phosphate bands (v1, v2, v3, v4), where the highest peak was at 960.3 cm-1 (v1) for both substrates. However, a 40% decrease in phosphate (v1) was detected in WSL. The peak at 1071 cm-1 was higher for sound enamel, indicating the presence of a phosphate band instead of the B-type carbonate. The spectra showed higher intensity of the organic composition at 1295 cm-1 and 1450 cm-1 for WSL. Conclusion: Non-invasive QLF, OCT and Raman spectroscopy were able to distinguish differences in fluorescence, optical properties, and organic/inorganic components, respectively, between sound enamel and WSL, validated by the destructive microhardness analysis.

Palavras-Chave: dentistry; enamels; caries; raman spectroscopy; diagnosis; corrosion denting

ARAUJO, ERIKA M. dos S.; VIDAL, CRISTINA de M.P.; FREITAS, ANDERSON Z. de; WETTER, NIKLAUS U.; MATOS, ADRIANA B. Characterization of sound enamel and natural white spot lesions. Brazilian Dental Science, v. 25, n. 4, p. 1-10, 2022. DOI: 10.4322/bds.2022.e3488. Disponível em: http://repositorio.ipen.br/handle/123456789/33577. Acesso em: $DATA.

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Abstract: Contamination of the aquatic environment by pharmaceuticals is becoming a global phenomenon of growing concern. Pharmaceuticals are partially metabolized, resulting in the excretion and release of residual into sewage, unaltered or metabolites. The wastewater treatment plants are not designed to eliminate these compounds, leading the residues into the aquatic environment. Besides, pharmaceuticals are not detected individually but as a complex mixture. Advanced oxidative processes have been applied as an alternative or complement to conventional sewage treatment processes, aiming the degradation and removal of toxic pollutants. The objective of this study was to evaluate the toxicity removal of mixtures of pharmaceuticals subjected to electron beam treatment. The aqueous solutions of each pharmaceutical were diluted in ultra-pure water and prepared in three pharmaceuticals combinations: Propranolol + Fluoxetine + Sulfadiazine; Propranolol + Fluoxetine + Diclofenac; Acetylsalicylic acid + Fluoxetine + Metformin). Electron Beam Accelerator was applied for the irradiations and the absorbed doses were 2.5-5.0 kGy. Acute toxicity tests with Daphnia similis were performed to evaluate the toxicity, before and after irradiation.. The data analyzed showed toxicity removal efficiency around 80% for the mixture of Propranolol, Fluoxetine and Diclofenac; 75% for the mixture of Propranolol, Fluoxetine and Sulfadiazine; and 30% for the mixture of Acetylsalicylic acid, Fluoxetine and Metformin. According to the literature, this is a viable technology for the removal of toxicity from pharmaceuticals, and the results demonstrated the potential of electron beam irradiation in reducing the toxicity of pharmaceutical from different classes.

Palavras-Chave: aquatic ecosystems; contamination; drugs; electron beams; environmental impacts; pollutants; radiation dose units; toxicity; waste water

BOIANI, N.F.; TOMINAGA, F.K.; BORRELY, S.I. Toxicity removal of pharmaceuticals mixtures through electron beam irradiation. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-11, 2022. DOI: 10.15392/2319-0612.2022.1838. Disponível em: http://repositorio.ipen.br/handle/123456789/33511. Acesso em: $DATA.

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Abstract: This article presents the results of applying three archaeometric techniques in archaeological ceramics from the upper river Madeira region in Amazonia. The first consists of the nuclear technique, neutron activation analysis (INAA), to identify the trace elements of the clay sources used in the production of the vessels. The second, non-nuclear X-ray diffraction (XRD), was used to characterise the mineral phases of each clay source. The third technique, electron paramagnetic resonance spectroscopy (EPR), estimated burning temperature related to the production stage of the artefacts. This approach made it possible to understand technological choices linked to selecting specific clay sources. The results suggest that different indigenous groups that inhabited the region between 940 and 760 B.P selected three clay sources to produce their vessels.

Palavras-Chave: archaeology; ceramics; mineralogy; rivers; chemical composition; clays; electron spin resonance

COSTA, A.F.; GOMES, D.M.C.; MUNITA, C.S.; BARIA, R.; TIZUKA, M.; KIPNIS, R.; WATANABE, S.; CHUBACI, J.F.D. Nuclear and non-nuclear analytical techniques applied to pre-colonial archaeological ceramics from the upper Madeira River/Brazil (940 to 760 B.P). Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-19, 2022. DOI: 10.15392/2319-0612.2022.1889. Disponível em: http://repositorio.ipen.br/handle/123456789/33509. Acesso em: $DATA.

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Abstract: The Brazilian Multipurpose Reactor (RMB) is a fundamental project that aims to turn Brazil into a self-sufficient country in the production of radioisotopes and radiopharmaceuticals to supply the Unified Health System (SUS) as much as the private institutions. In addition, the RMB project describes other applications as irradiation and testing of nuclear fuels and structural material analysis, for instance. There are many techniques in the project to study structural aspects of materials, where neutron diffraction represents one of the priorities for implementation. This technique will take place mainly on two diffractometers on Thermal Neutron Guide 1 (TG1), namely Araponga, a high-resolution diffractometer, and Flautim, a high-intensity diffractometer. In this work, we study the performance of the Araponga diffractometer through McStas simulations with input produced by the MCNP code of the RMB core. We investigate the neutron flux values considering a state-of-art high-resolution diffractometer, and the results are promising since some simulated scenarios present values compatible with high-intensity devices.

Palavras-Chave: computerized simulation; diffractometers; monte carlo method; neutron diffraction; neutron flux; neutron sources; rmb reactor

SOUZA, A.P.S.; OLIVEIRA, L.P. de; GENEZINI, F.A.; SANTOS, A. dos. Simulating Araponga: the high-resolution diffractometer of Brazilian Multipurpose Reactor. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-10, 2022. DOI: 10.15392/2319-0612.2022.1861. Disponível em: http://repositorio.ipen.br/handle/123456789/33507. Acesso em: $DATA.

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Abstract: The approach taken in the WHO Guidelines for controlling radiological hazards in public water supplies has two stages. The first is an initial screening for gross alpha and beta activity to determine whether the activity concentrations are below levels at which no further action is required; and if these screening levels are exceeded, investigation of the concentration of individual radionuclides and comparison with specific guidance levels. Mineral water is obtained directly from natural sources or by extracting groundwater, it is characterized by the quantity of mineral salts, trace elements and other constituents. The bottled water industry is present in the major regions of the world, and the population consumption has increased every year in Brazil and world, also increasing new mineral water mining sites, so it is necessary to constantly check the amount of radioactivity in mineral water. The aim of this study is to quantify the concentration of the natural radionuclides in the bottled mineral water consumed in São Paulo city. The bottled mineral water samples were purchased in a supermarket in São Paulo, with 23 different brands. The determination of gross alpha and beta activity concentration in bottled mineral water by Liquid Scintillation Counting measurement was performed using a 1220 Quantulus™ Ultra Low-Level Liquid Scintillation Spectrometer. The natural radionuclides (226Ra, 228Ra, 210Pb and 40K) were measured by gamma spectrometry, using an HPGe detector. The results obtained in this study can be used for a database on bottled mineral water radioactivity from Brazil.

Palavras-Chave: natural radioactivity; drinking water; effective radiation doses; lead 210; potassium 40; radon 226; radon 228; radiation effects; radiation protection; radioecological concentration; recommendations

NISTI, M.B.; NERY, A.D.; SAUEIA, C.H.R.; CAVALCANTE, F. Assessment of natural radioactivity in bottled mineral water from Brazil. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-15, 2022. DOI: 10.15392/2319-0612.2022.1795. Disponível em: http://repositorio.ipen.br/handle/123456789/33505. Acesso em: $DATA.

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Abstract: Nuclear technologies and radiation have offered technological and scientific growth nowadays, but there is a frequent paradox in this. While these technologies substantially increase the quality of human life, they also produce radioactive waste, which, when not properly managed, can generate risks that threaten to harm the environment and health. As a result, in risk management of radioactive waste, decision-making processes need to be guided by a framework of principles, including the precautionary and preventive principles. For this reason, the present work proposes to develop a legal analysis on radioactive waste risk management using the principles of precaution and prevention. These principles have similarities, but it is the differences in their structure that deserve to be highlighted, which is discussed and exemplified throughout this work. Furthermore, national and international experience in environmental damage has taught us that an identification and assessment of risk is necessary, because if preventive measures are not taken radioactive waste can be dispersed and harm the environment. When it comes to assessing the risk of radioactive waste, one of the precautionary measures is the application of a conservative stance in modelling scenarios, as there are still uncertain risks. Therefore, comprehending the different circumstances surrounding precautionary and preventive measures and having effective information about risk is essential for successful risk management.

Palavras-Chave: radioactive wastes; risk assessment; environment; laws; environmental policy

ANDRADE, M.V.; VICENTE, R. Precautionary and preventive measures in Brazilian law applied to radioactive waste management. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-17, 2022. DOI: 10.15392/2319-0612.2022.1899. Disponível em: http://repositorio.ipen.br/handle/123456789/33503. Acesso em: $DATA.

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Abstract: Assessment of heavy metal content in biological fluids is essential to determine human and animal health due to exposure to contaminated environments, food and water. WDXRF is a non-destructive method that involves no chemical treatments. It is possible to perform fast chemical analysis without producing hazardous waste and uses a small sample volume (± 50 μL), which is helpful for veterinary usage. Therefore, this work aimed to implement an alternative method for minor and trace elements in blood serum samples of dairy cattle (Bos taurus) using WDXRF. It was implemented to determine Al, Cr, Co, Fe, Cu, and As. The method was evaluated by comparing WDXRF and ICP-OES results of a set of 14 blood serum samples of dairy cattle using principal component analysis (PCA). Results of WDXRF and ICP-OES were statistically equivalent to all analyzed elements, except for Fe and Al, which were still comparable. WDXRF proved to be a suitable alternative methodology for heavy metal detection in animal blood serum samples due to the low sample volume. The results of this study enable a new and fast method for veterinary internal medicine, which detects elevated levels of toxic elements in animal blood samples to ensure the correct protocols to prevent the animal's death.

Palavras-Chave: absorption spectroscopy; blood serum; cattle; elements; trace amounts; veterinary medicine; x-ray fluorescence analysis

GAETA, N.C.; CARVALHO, D.U.O.G.; ALEMAN, M.A.R.; CARVALHO, J.S.; CEDRAZ, P.P.; ULRICH, J.C.; JOVANE, L.; GREGORY, L.; SCAPIN, M.A. Quantitative analysis of minor and trace elements in blood serum of dairy cattle (Bos taurus) by WDXRF. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-10, 2022. DOI: 10.15392/2319-0612.2022.1911. Disponível em: http://repositorio.ipen.br/handle/123456789/33501. Acesso em: $DATA.

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Abstract: A recent and growing concern in environmental studies is the presence of antibiotics in wastewater, which contributes to antimicrobial resistance building. Amoxicillin, according to the World Health Organization, is one of the most consumed antibiotics worldwide, for being a first line therapy for common infections. Among several drug degradation methodologies, electron beam irradiation (EBI) is presented as an efficient and green treatment. This work presents data on amoxicillin degradation via EBI. Degradation rate was evaluated by LC/MS-MS, carbon removal efficiency was evaluated by TOC and ecotoxicity assays were performed employing Vibrio fischeri. Chromatographic results indicate an efficiency removal of 97.65% at 0.75 kGy and concentration below the limit of detection with increasing absorbed dose. Low mineralization (up to 10%) was achieved at 3.0 kGy. Regarding toxicity, approximately 81% of toxicity removal was obtained at 0.75 kGy and a decrease in efficiency was achieved with higher doses. In conclusion, results indicate the low doses (0.75 kGy) as most effective for drug removal employing EBI.

Palavras-Chave: antibiotics; waste water; water pollution; toxicity; decomposition; detoxification; electron beams; ionizing radiations; irradiation

BORRELY, S.I.; REDÍGOLO, M.M.; VILLARD, B.D.; LEBRE, D.T.; TOMINAGA, F.K. Degradation and toxicity of amoxicillin after electron beam irradiation. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-8, 2022. DOI: 10.15392/2319-0612.2022.1894. Disponível em: http://repositorio.ipen.br/handle/123456789/33499. Acesso em: $DATA.

Esta referência é gerada automaticamente de acordo com as normas do estilo IPEN/SP (ABNT NBR 6023) e recomenda-se uma verificação final e ajustes caso necessário.

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Abstract: The Calibration Laboratory (LCI) of the Nuclear and Energy Research Institute (IPEN-CNEN) offers calibration services for radiation measurements instruments used in radiation protection, diagnostic radiology and radiotherapy. LCI produces radiation qualities and irradiation conditions which are in accordance with the national and international standard requirements. In order to establish the recommended radiation qualities for diagnostic radiology, X-ray beams generated in laboratory are modified for the irradiation conditions found in equipment routinely used in healthcare services. In this work, a new additional filtration system was developed to be adapted to the existing filter system at LCI. The new filter support can be coupled to the PTW Bench Control installed at the LCI X-ray system. Using a FDM 3D printer, a support model and a set of drawers were developed for the placement of additional filters. The models were also developed to fit each specific drawer of each filter to be used in the laboratory routine, coupled to the specific sensors that fit the spaces of the support part. Additionally, a microcontroller based on Arduino, micro switches, low- and high-level programming, allow checking of drawer status and integration of information with the laboratory control system. The system allows the recognition of the filter inserted in the drawer from sensors attached to the support. Tests were carried out to verify the usability of the system in the routine, adding Ag (silver) and Cu (copper) filters, for the characterization of attenuated radiation beams of interest in diagnostic radiology.

Palavras-Chave: magnesium base alloys; biological materials; biodegradation; decomposition; fluorescence spectroscopy; x radiation; specifications