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VIS-active TiO2 films decorated by expanded graphite
2024 - BENTO, RODRIGO T.; CORREA, OLANDIR V.; GASTELOIS, PEDRO L.; PILLIS, MARINA F.
TiO2/C nanocomposite films were applied on water treatment. Expanded graphite nanosheets (EG) were obtained by UVC-assisted liquid-phase exfoliation technique, without the addition of acids, surfactants, or aggressive oxidizing agents, which characterizes the process as an eco-friendly method. The carbon nanosheets were synthesized directly from graphite bulk at different times and deposited on TiO2 films surface by airbrush spray coating method, forming a TiO2/C heterojunction. The increase in the exfoliation time promoted a more efficient photocatalytic dye removal under visible light. Morphological modifications, changes in the electronic structure, and wide range of light absorption were observed from the TiO2/C heterojunction formation. The results showed that hybrid TiO2/C supported photocatalyst is a promise alternative for practical photocatalytic applications under sunlight.
Ceramic compositions for 5G devices containing niobium
2024 - MUCCILLO, REGINALDO; MUCCILLO, ELIANA N.S.
The main dielectric properties of several ceramic materials having niobium in their composition, proposed to take part in 5G telecommunication devices, are reviewed. A preliminary basic presentation of 5G systems, the requirements for implementing their use, a concise review of the ceramic compositions containing niobium that have been studied thus far, and an evaluation of their performance are detailed. A survey is presented, including more than 80 different compositions containing niobium, focusing on key parameters, such as dielectric constant, quality factor, temperature coefficient, and sintering temperature. These parameters play a role for assessing the potential application of these ceramics in 5G devices.
Effect of cerium addition on the microstructure and shape memory properties of austenitic Fe–Mn–Si–Cr–Ni alloys
2024 - SILVA, RODRIGO da; BARONI, LUIS F.S.; MARTINS JUNIOR, CLAUDIO B.; MAGALHAES, DANIELLE C.C.; VACCHI, GUILHERME S.; KLIAUGA, ANDREA M.; LIMA, NELSON B.; OTUBO, JORGE; DELLA ROVERE, CARLOS A.
The addition of rare earth elements, such as cerium, to austenitic Fe-Mn-Si-based shape memory alloys has been shown to improve both corrosion resistance and shape recovery. However, the mechanisms underlying the effect of Ce on shape recovery are still unclear. This study investigates the influence of the addition of small amounts of Ce (0.18, 0.42, and 0.96 wt%) on the microstructure and shape recovery of an austenitic Fe-13.50Mn-3.98Si-9.54Cr-4.51Ni alloy. Ce additions induce the formation of a large number of Ce-rich particles, which act as austenitic grain refiners. Both grain refinement and the formation of Ce-rich particles contribute to the strengthening of the matrix at 0.42 wt% Ce addition. In addition, Ce additions alter the MS temperature, which increases with Ce additions. Total shape recovery improves with 0.18 and 0.42 wt% Ce additions, but decreases with 0.96 wt% Ce addition. The beneficial effect of Ce addition in improving the shape recovery of the austenitic Fe-Mn-Si-Cr-Ni alloy is related to the enhancement of the elastic shape recovery component of the total shape recovery. However, the shape memory recovery due to the shape memory effect always decreases with the increase of the Ce content.
Binder‑free textile PAN‑based electrodes for aqueous and glycerol‑based electrochemical supercapacitors
2024 - BARBOSA, INGRID A.B.; MARCUZZO, JOSSANO S.; COSENTINO, IVANA C.; FARIA JUNIOR, RUBENS N. de
Amidst different types of energy storage systems, electrochemical supercapacitors have received considerable attention as they close the gap between electrolytic capacitors and batteries. This work addresses electric double-layer capacitors (EDLCs), a type of electrochemical supercapacitor, and has been divided into two parts. In the former, the synthesis and characterization of activated carbon fiber-felt (ACFF) electrodes, derived from textile PAN-based fiber, have been provided. In the latter, the electrochemical characterization of EDLCs in potassium hydroxide solutions ( aqueous electrolytes) and in potassium hydroxide-glycerol hybrid electrolytes (glycerol-based electrolytes) have been investigated. The synthesis of ACFF electrodes via two-step oxidation, carbonization, and physical activation resulted in low-cost and binder-free electrodes containing 87% of the total volume of pores as micropores (maximum pore width of 3 nm) and a high specific surface area of 1875 m(2) g(-1). Electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic charge-discharge techniques were carried out in a symmetric two-electrode setup at room temperature. The results showed that ACFF electrodes are suitable for aqueous electrolytes, particularly 2 M KOH, and KOH:GLY (3:1), a glycerol-based electrolyte. Although KOH:GLY (3:1) exhibited high electrolyte resistance (34 +/- 3 Omega), this hybrid green-electrolyte supports a potential window that is twice greater than that of aqueous electrolytes. In addition, glycerol, commonly called glycerin, is a by-product of FAME (fatty acid methyl ester) biodiesel, which is the major source of glycerol. Glycerol-based electrolytes are promising green electrolytes for EDLCs. Therefore, it is necessary to decrease its viscosity and resistance.
Use of collagen and auricular cartilage in bioengineering
2024 - MASSIMINO, LIVIA C.; MARTINS, VIRGINIA da C.A.; VULCANI, VALCINIR A.S.; OLIVEIRA, EVERTON L. de; ANDREETA, MARIANE B.; BONAGAMBA, TITO J.; KLINGBEIL, MARIA F.G.; MATHOR, MONICA B.; PLEPIS, ANA M. de G.
The aim of this study was the development of collagen and collagen/auricular cartilage scaffolds for application in dermal regeneration. Collagen was obtained from bovine tendon by a 72 h-long treatment, while bovine auricular cartilage was treated for 24 h and divided into two parts, external (perichondrium, E) and internal (elastic cartilage, I). The scaffolds were prepared by mixing collagen (C) with the internal part (CI) or the external part (CE) in a 3:1 ratio. Differential scanning calorimetry, scanning electron microscopy (SEM) analysis, microcomputed tomography imaging (micro-CT) and swelling degree were used to characterize the scaffolds. Cytotoxicity, cell adhesion, and cell proliferation assays were performed using the cell line NIH/3T3. All samples presented a similar denaturation temperature (Td) around 48 degrees C, while CE presented a second Td at 51.2 degrees C. SEM micrographs showed superficial pores in all scaffolds and micro-CT exhibited interconnected pore spaces with porosity above 60% (sizes between 47 and 149 mu m). The order of swelling was CE < CI < C and the scaffolds did not present cytotoxicity, showing attachment rates above 75%-all samples showed a similar pattern of proliferation until 168 h, whereas CI tended to decrease after this time. The scaffolds were easily obtained, biocompatible and had adequate morphology for cell growth. All samples showed high adhesion, whereas collagen-only and collagen/external part scaffolds presented a better cell proliferation rate and would be indicated for possible use in dermal regeneration.
Calculation of the budget of uncertainty on measurements size nanoparticles using dynamic light scattering
2024 - GERALDES, ADRIANA N.; ROSERO, WILMMER A.A.; ROSTELATO, MARIA E.C.M.; SARKIS, JORGE E.S.
Accurate nanoparticle characterization is essential since it can significantly affect its physicochemical and biological properties. Among physicochemical properties used to characterize nanomaterials, size and size distribution are essential and should be assessed before surveying poisonousness or biocompatibility. Several methods are suitable to evaluate these characteristics including the dynamic light scattering. The aims of the present paper were to propose a methodology to measure nanoparticle size and present the estimation of the particle size uncertainty using the dynamic light scattering technique. The reliability of measurements was ensured by a series of handling precautions and quality criteria for good measurements to be applied for methodology validation using reference material polyvinylpyrrolidone coated silver nanoparticles. The identification and quantification of input quantities to the measurement uncertainties were estimated. The uncertainty concerning the equipment was 1.2% while the repeatability obtained was 1.4%, within the range of values stipulated in the reference standard (less than 5%). The relative standard uncertainties of trueness and repeatability were below the thresholds defined by the International Organization for Standardization. The result of the expanded uncertainty was 3.9% with 95% coverage probability for the reference material.
Assessment of the IEA-R1 nuclear reactor using a nonstandard fuel assembly with six fuel plates of the Brazilian Multipurpose Reactor
2024 - SOARES, HUMBERTO V.; TORRES, WALMIR M.; UMBEHAUN, PEDRO E.; BELCHIOR, ANTONIO; ANDRADE, DELVONEI A. de
In order to qualify the fuel plates of the Brazilian Multipurpose Reactor (RMB), a nonstandard Instrumented Fuel Assembly (IFA) was designed and is being constructed to be burned in the IEA-R1 nuclear research reactor. IFA has fuel plates of different uranium densities (10 fixed fuel plates of 3.0 gU/cm3 – IEA-R1 standard; 6 removable fuel plates of 3.7 gU/cm3 – RMB; and a central aluminum plate). This paper is the first step to demonstrate that IEA-R1 can safely operate with this IFA. To verify the IFA thermal behavior inside the IEA-R1 core during reactor operation and certify the no power peaks occurrence, the power distribution was calculated for each fuel plate. LEOPARD and HAMMER-TECHNION codes were utilized to calculate the core thermal neutron cross section and CITATION code to calculate the core power distribution. Calculations were performed for 5 MW reactor power considering the IFA placed in a core peripheral position. The RMB fuel plates average power was 4.73 % higher compared to IEA-R1 fuel plates. This was expected due to the higher density of uranium in these plates. The power of each IFA fuel plate was compared with a fresh IEA-R1 Fuel Assembly (FA) at the same core position. The power in the IFA hottest plate is only 6.79 % higher than the correspondent IEA-R1 fuel plate. The IFA power distribution was also compared to the hottest FA of the core. The power of each IFA fuel plate was below its correspondent hottest FA fuel plate. In addition, the total IFA power is 18.40 % less than the hottest FA in the core. No significant power peaks occur in the IFA during operation. As future works, thermal–hydraulic calculations will be performed considering this calculated power distribution and no hot spots are expected.
Analysis of the luminescent emission during flash sintering of 8YSZ and 20SDC ceramics
2024 - MUCCILLO, REGINALDO; DIAZ, JULIO C.C.A.; MUCCILLO, ELIANA N.S.
Light-emission data were collected before, during, and after the occurrence of the flash event in pressureless electric-field-assisted (flash) sintering experiments on ZrO2: 8 mol% Y2O3 (8YSZ) and CeO2: 20 mol% Sm2O3 (20SDC) ceramic green pellets to analyze the luminescent emission from the samples. The experiments were performed at 800 degrees C with an applied electric field of 100 V center dot cm-1 at 1 kHz, limiting the electric current to 1 A. Luminescence data were obtained in the 200-1200 nm (ultraviolet-visible-near-infrared) range. The deconvolution of the optical spectra allowed for the identification of emission bands in the visible range due exclusively to the samples. The wavelength maxima of the emission bands in 8YSZ were found to be different from those in 20SDC. It is suggested that these bands might originate from the interaction of the electric current, resulting from the application of the electric field, with the depleted species located at the space-charge region at the grain boundaries of these ceramics. The main results represent a contribution to help to clarify the mechanisms responsible for the fast densification with inhibition of grain growth in electroceramics.
Recognition of breast cancer subtypes using FTIR hyperspectral data
2024 - FAROOQ, SAJID; DEL-VALLE, MATHEUS; SANTOS, SOFIA N. dos; BERNARDES, EMERSON S.; ZEZELL, DENISE M.
Fourier -transform infrared spectroscopy (FTIR) is a powerful, non-destructive, highly sensitive and a promising analytical technique to provide spectrochemical signatures of biological samples, where markers like carbohydrates, proteins, and phosphate groups of DNA can be recognized in biological micro -environment. However, method of measurements of large cells need an excessive time to achieve high quality images, making its clinical use difficult due to speed of data -acquisition and lack of optimized computational procedures. To address such challenges, Machine Learning (ML) based technologies can assist to assess an accurate prognostication of breast cancer (BC) subtypes with high performance. Here, we applied FTIR spectroscopy to identify breast cancer subtypes in order to differentiate between luminal (BT474) and nonluminal (SKBR3) molecular subtypes. For this reason, we tested multivariate classification technique to extract feature information employing three -dimension (3D) -discriminant analysis approach based on 3D -principle component analysis -linear discriminant analysis (3D-PCA-LDA) and 3D -principal component analysis -quadratic discriminant analysis (3D-PCA-QDA), showing an improvement in sensitivity (98%), specificity (94%) and accuracy (98%) parameters compared to conventional unfolded methods. Our results evidence that 3D-PCALDA and 3D-PCA-QDA are potential tools for discriminant analysis of hyperspectral dataset to obtain superior classification assessment.
Development of a pulsed laser deposition system suitable for radioactive thin films growth
2024 - MACHADO, N.G.P.; GENEZINI, F.A.; RAELE, M.P.
Radioactive thin films have a direct application in the development of beta-voltaic batteries. The main advantage of that kind of nuclear battery is its durability, which can range from a hundred years, depending on the half-life of the radioisotope used. In this context, Pulsed Laser Deposition (PLD) is an important tool. A relevant aspect of a system using this technique is that the main equipment is outside the chamber where the material is processed. Consequently, this feature allows the growth of radioactive thin films, as it enables the development of an arrangement where the contaminated area is controlled. In this way, the present work proposed the development of a PLD system for the growth of radioactive thin films. The PLD system was then implemented and radioactive copper targets were processed for 60 min and 120 min, resulting in radioactive thin films with an average thickness of (167.8 ± 3.7) nm and (313.5 ± 9.2) nm, respectively. Then, a study was performed about the radioactive contamination spread in the PLD system in order to prove if the filtering implemented was effective in retaining the contamination inside the vacuum chamber. Thus, it is demonstrated for the first time the feasibility of using the PLD technique in the growth of radioactive thin films, making its use possible in future studies on the development of beta-voltaic nuclear batteries.
Interlaboratory comparison of two homemade pencil type ionization chambers
2024 - CASTRO, M.C.; SILVA, N.F.; CALDAS, L.V.E.
Computed tomography (CT) is a diagnostic exam responsible for the highest dose values received by the patients during the procedure. Over the years, this kind of equipment has been improved to ensure that the patients do not receive unnecessary doses. For this reason it is important to keep a quality control program for the CT equipment. To perform the dosimetry in CT beams, the instrument used is usually a pencil type ionization chamber with a sensitive volume length of 10 cm. However, this kind of detector is available with different sensitive volume lengths. The aim of this study was to compare the response of two homemade pencil type ionization chambers with sensitive volume lengths of 10 cm and 30 cm in the laboratories of Instituto de Pesquisas Energéticas e Nucleares (IPEN, Brazil) and National Physical Laboratory (NPL, UK). The characterization tests were performed, and the results obtained are within the international recommended limits. The only difference observed in the response of the two chambers in both laboratories is the fact that the ionization current obtained in all the tests at the IPEN is higher than at the NPL, because of the beam characteristics.
Biogas potential of biowaste
2024 - OLIVEIRA, HELENA R.; KOZLOWSKY-SUZUKI, BETINA; BJORN, ANNIKA; YEKTA, SEPEHR S.; CAETANO, CRISTIANE F.; PINHEIRO, ERIKA F.M.; MAROTTA, HUMBERTO; BASSIN, JOAO P.; OLIVEIRA, LUCIANO; REIS, MARCELO de M.; SCHULTZ, MARIO S.; MANGIAVACCHI, NORBERTO; FERREIRA-LEITAO, VIRIDIANA S.; FASHEUN, DANIEL O.; SILVA, FERNANDA G.; TAVEIRA, IGOR; ALVES, INGRID R. de F.S.; CASTRO, JULIA; DURAO, JULIANA V.; GUIMARAES, JULIANA; ROCHA, MARIANA E.; TOMASINI, MARINA; MARTINS, PEDRO V. de O.; PRESCILIANO, ROGERIO; SANTOS, STELLA B. dos; FARIA, TAMIRES M.; CORREA, TARCISIO; LINDE, THIAGO de N.M.P. de; ABREU, FERNANDA; ENRICH-PRAST, ALEX
Anaerobic digestion has been widely applied for waste treatment, renewable energy generation , biofertilizer production. The biogas potential in Brazil is sizable, but the state of Rio de Janeiro is largely dependent on fossil fuels , there is a lack of biogas potential assessments in the state. Thus, this study evaluated biomethane, electricity and biofertilizer potentials in the region. Three different scenarios of biomass supply were considered for four major biowaste streams: sewage sludge; cattle manure; sugarcane processing waste; and food waste. Biomethane generation from the assessed sources could reach 0.6-1.3 billion Nm(3) year(-1), corresponding to 1,768-3,961 GWh year(-1) of electricity , 1.6-3.3 million Mg year- 1 of biofertilizer. Cattle manure was responsible for 73-84% of the projected biomethane production, presenting an opportunity to reduce the sig-nificant emissions from livestock farming. The estimated biofertilizer production could meet the demands of the state , the produced electricity could offset up to 10% of the demand. The gas grid could facilitate the dis-tribution of upgraded biomethane, and 10-22% of the natural gas demand could be met. The findings of this work highlight the high potential for biogas generation in Rio de Janeiro, which is up to seven times larger than the current production.
Evaluation of low-kV energy X-ray radiation effect on breast cancer cells incubated with gold nanoparticles capped with aminolevulinic acid, methyl aminolevulinate, and gamma-aminobutyric acid
2024 - LOPES, ISABELA S.; SANTOS, NOEMY R.; SILVA, GIOVANA D. da; SANTOS, LEONARDO C. dos; POTIENS, MARIA da P.A.; VIEIRA, DANIEL P.; COURROL, LILIA C.
Gold nanoparticles (AuNPs) have unique properties, including size-dependent optical and electronic characteristics, biocompatibility, and ease of functionalization, making them attractive for various diagnostic and therapeutic applications. The goal of this work was to verify the potential application of gold nanoparticles capped with aminolevulinic acid (ALA), methyl aminolevulinate (MALA), and gamma-aminobutyric acid (GABA) in lowenergy X-ray diagnostics and therapy of breast cancer. ALA and MALA induce the accumulation of protoporphyrin IX (PpIX) in cancer cells. PpIX, in turn, can be excited by Cherenkov radiation, producing reactive oxygen species after energy or electron transfer from the triplet excited state of PpIX to molecular oxygen, which induces cell death by apoptosis or necrosis. The results indicated that ALA and MALA nanoparticles promoted reduced cell viability by approximately 20 % with X-ray irradiation at an energy level of 35 kV for 5 min. Breast cancer cells possess GABA receptors, allowing for targeted effects by GABANPs, which can enhance contrast and improve diagnostic potential. GABAAuNPs also demonstrated decreased cell viability in similar to 10 % following X-ray irradiation, making them a promising material for breast cancer diagnosis and treatment.
Thermal fatigue of Zircaloy‑4 cladded U‑7.5Nb‑2.5Zr
2024 - MORAIS, NATHANAEL W.S.; MONLEVADE, EDUARDO F.; SCHON, CLAUDIO G.
Prototype plates made of U-7.5Nb-2.5Zr alloy, also known as Mulberry alloy, cladded with Zircaloy-4 were thermally fatigued between 200 ºC and 500 ºC investigated. The assembly consisting of a Uranium alloy monolithic core and the Zircaloy-4 cladding was processed by hot rolling and investigated in the “as rolled” state, as well as after applying 9% and 18% reduction in cold rolling. The samples were characterized by Optical microscopy and X-Ray diffraction both before and after the thermal cycling. All samples presented strong volume contraction (shrinkage) in the first thermal cycle, observed concomitantly with the γ → α" transformation. The relative shrinkage varied with the cold rolling level, being larger for the “as rolled” plate. The failure mechanism observed in all plates was fracture alongside the U-alloy/Zircaloy-4 interface and no transverse crack was observed either in the Zircaloy-4 sheet or in the Uranium core.
The dual effect of Selenium nanoparticles in rice seedlings
2024 - FREIRE, BRUNA M.; LANGE, CAMILA N.; CAVALCANTI, YASMIN T.; MONTEIRO, LUCILENA R.; PIERETTI, JOANA C.; SEABRA, AMEDEA B.; BATISTA, BRUNO L.
Selenium deficiency has been a worldwide concern because it can pose a risk to human health. Selenium nanoparticles (SeNPs) are in general less toxic and more bioavailable than ionic Se and, therefore, their use for biofortification of food crops has attracted attention. Rice is a staple food consumed by half of the world's population. Indeed, studies on SeNPs' impacts on oxidative stress and antioxidant responses in rice seedlings are scarce. Herein, the effect of different concentrations of SeNPs on growth, antioxidant enzyme activity, reactive oxygen species, and nitric oxide metabolites in rice germinating seeds were investigated. Results revealed a dual effect of SeNPs on seedling growth. At low concentrations (0.5 mg L -1), the nanoparticles did not affect seedling growth, while at higher concentrations root elongation was significantly decreased. Soaking rice seeds with SeNPs at 0.5 mg L - 1 effectively improved the activity of ascorbate peroxidase, catalase, and superoxide dismutase enzymes. However, a decrease in antioxidant enzyme activity was observed with increasing SeNPs concentrations. All treatments decreased S-nitrosothiols and nitrite concentrations compared to the control. Hydrogen peroxide concentrations also decreased for concentrations higher than 5 mg L - 1, compared to the control. Our results suggest a beneficial effect of SeNPs at the optimal concentration of 0.5 mg L - 1 on stimulating antioxidant metabolism and mitigating reactive oxygen species in plant tissues without affecting the physiological parameters.
Low-cost experiments for teaching eletrostatics in Brazilian high school
2024 - JULIATTO, HENRIQUE M.; MARTINS, MATHEUS A.; KUSMAN, MATHEUS; YOKAICHIYA, FABIANO; FRANCO, MARGARETH K.K.D.
Many public schools in Brazil do not have the financial resources to obtain certain equipment for teaching physics. Considering that the Brazilian National Common Curricular Base, a normative document that defines the organic and progressive set of essential learning that all students must develop, determines that the curriculum for teaching electromagnetism for high school encompass electrostatics. It is very important that schools offer laboratory conditions. For this reason, it was proposed to design simple and low-cost construction equipment, so that teachers from the basic education network can build them for their schools, thus improving the quality of teaching for their students. This study aims to gather equipment and experiments, such as electroscope, electrophorus, Leyden jar and Van de Graaf generator, which can be used in the classroom for didactic purposes in physics teaching. The main focus of this work is the construction of equipment for the implementation of a laboratory for the study of electrostatics, which addresses physical concepts seen by high school students of the basic network in Brazil.
Review of advances in coating and functionalization of gold nanoparticles
2024 - ROSERO, WILMMER A.A.; BARBEZAN, ANGELICA B.; SOUZA, CARLA D. de; ROSTELATO, MARIA E.C.M.
Nanoparticles, especially gold nanoparticles (Au NPs) have gained increasing interest in biomedical applications. Used for disease prevention, diagnosis and therapies, its significant advantages in therapeutic efficacy and safety have been the main target of interest. Its application in immune system prevention, stability in physiological environments and cell membranes, low toxicity and optimal bioperformances are critical to the success of engineered nanomaterials. Its unique optical properties are great attractors. Recently, several physical and chemical methods for coating these NPs have been widely used. Biomolecules such as DNA, RNA, peptides, antibodies, proteins, carbohydrates and biopolymers, among others, have been widely used in coatings of Au NPs for various biomedical applications, thus increasing their biocompatibility while maintaining their biological functions. This review mainly presents a general and representative view of the different types of coatings and Au NP functionalization using various biomolecules, strategies and functionalization mechanisms.
Radiosynthesis standardization and preclinical assessment of the [68Ga]Ga-DOTA-Ubiquicidin29-41
2024 - MIRANDA, ANA C.C.; FUSCALDI, LEONARDO L.; MEJIA, JORGE; SILVA, FABIO F.A. da; TURATO, WALTER M.; MENDONCA, FERNANDA F.; NOGUEIRA, SOLANGE A.; OSAWA, AKEMI; YAMAGA, LILIAN Y.I.; MALAVOLTA, LUCIANA; BARBOZA, MARYCEL F. de
Human bacterial infections significantly contribute to the increase in healthcare-related burdens. This scenario drives the study of novel techniques for the early and precise diagnosis of infectious processes. Some alternatives include Nuclear Medicine- and Molecular Imaging-based strategies. However, radiopharmaceuticals that are available for routine assessments are not specific to differentiating infectious from aseptic inflammatory processes. In this context, [Ga-68]Ga-DOTA-Ubiquicidin(29-41) was synthesized using an automated module and radiochemical; in vivo and in vitro studies were performed. The radiopharmaceutical remained stable in saline (up to 180 min) and in rodent serum (up to 120 min) with radiochemical purities > 99 and 95%, respectively. Partition coefficient and serum protein binding at 60 min were determined (-3.63 +/- 0.17 and 44.06 +/- 1.88%, respectively). Ex vivo biodistribution, as well as in vivo microPET/CT images in mice, showed rapid blood clearance with renal excretion and reduced uptake in other organs in Staphylococcus aureus-infected animals. Higher uptake was observed in the target as compared to the non-target tissue (p < 0.0001) at 60 min post administration. The presented in-human clinical case demonstrates uptake of the radiopharmaceutical by Staphyloccocus aureus bacteria. These results indicate the potential of [Ga-68]Ga-DOTA-Ubiquicidin(29-41) as a radiopharmaceutical that can be obtained in a hospital radiopharmacy for the diagnosis of infectious processes using PET/CT.
Novel resin-based material containing β-tricalcium phosphate nanoparticles for the reduction of dentin permeability
2024 - LIMA, LEONARDO C.; SILVA, FLAVIA R.O.; VIANA, ITALLO E.L.; DENUCCI, GIOVANNA C.; MUMAW, CHRISTEN L.; WALKER, CHANDLER; HARA, ANDERSON T.; SCARAMUCCI, TAIS; SOCHACKI, SABRINA F.
Objectives: To synthesize and characterize a novel dentin adhesive containing Beta-Tricalcium Phosphate (beta-TCP) nanoparticles and test its ability to reduce dentin permeability (dP). Methods: Experimental adhesives were prepared by mixing Bis-GMA, TEGDMA, HEMA (50/25/25 wt.%), photoinitiators, and inhibitors. The following groups were tested: Experimental adhesives without beta-TCP (Exp.); with 10 wt.% beta-TCP (Exp.10 wt.% beta-TCP); with 15 wt.% beta-TCP (Exp.15 wt.% beta-TCP), Scotchbond Multi-Purpose (SBMP) and Clearfil SE Protect Bond (CFPB). Degree of conversion (DC%, 10 and 20 s); Flexural Strength (FS), Knoop Hardness (KHN), and Cell Viability (OD%) tests were performed. dP was evaluated by hydraulic conductance, using human dentin disks (n=12), at three-time intervals: post-EDTA (T0); post-treatment (T1); and post-erosion/abrasion cycling (T2). Data were statistically analyzed (alpha=0.05). Results: For all groups, exposure time for 20 s presented a higher DC% than for 10 s. For FS, filled adhesives did not differ from unfilled and from CFPB. Experimental adhesives did not differ among them and showed lower KHN than the commercial products. Cell viability did not differ among adhesives, except Exp. 15 wt.%, which showed lower OD% than Exp., Exp. 10% and, CFPB. For dP, only Exp.10 and 15 wt.% beta-TCP did not present difference between the times T1 and T2. After cycling, Exp.10 wt.% beta-TCP presented lower permeability than Exp. and CFPB. Conclusions: The incorporation of 10 wt.% beta-TCP nanoparticles into the resin-based dental material did not affect its mechanical properties and biocompatibility, and promoted the greatest reduction in dentin permeability, sustaining this effect under erosive/abrasive challenges. Clinical significance: A novel resin-based dental material containing beta-TCP nanoparticles was able to reduce dentin permeability, maintaining its efficacy after erosive/abrasive challenges. The synthesized material did not affect dental pulp cell viability and might be promising for other conditions that require dental remineralization, such as tooth wear and dental caries.
Investigation of 76Se(18O, 17O)75Se and 76Se(18O, 19F)75As transfer reactions at 15 MeV/u in a multi-channel approach within the NUMEN project
2024 - CIRALDO, I.; CAPPUZZELLO, F.; CAVALLARO, M.; CARBONE, D.; GARGANO, A.; DE GREGORIO, G.; GARCIA-TECOCOATZI, H.; SANTOPINTO, E.; MAGANA-VSEVOLODOVNA, R.I.; ACOSTA, L.; AGODI, C.; AMADOR-VALENZUELA, P.; BRISCHETTO, G.A.; BURRELLO, S.; CALVO, D.; CHAVEZ LOMELI, E.R.; COLONNA, M.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; GUAZZELLI, M.A.; HACISALIHOGLU, A.; LINARES, R.; MEDINA, N.H.; MORALLES, M.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; SGOUROS, O.; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; SPATAFORA, A.; TORRESI, D.; TUDISCO, S.; YILDIRIM, A.; ZAGATTO, V.A.B.
A full-comprehensive study of heavy-ion induced nuclear reactions is a powerful tool to characterize nuclear mean-field features as well as fewnucleon correlations in low-lying nuclear states. In this context, the investigation of 76Se(18O, 17O)75Se and 76Se(18O, 19F)75As transfer reactions was performed with the NUMEN project, aiming at providing data-driven information to constrain nuclear structure models for the 76Se nucleus. This nucleus is under investigation since it is the daughter nucleus of 76Ge in the neutrinoless double beta decay (0νββ) process. The experiment was performed at INFN-LNS where the 18O beam impinged the 76Se target and the reaction ejectiles were momentum analyzed by the MAGNEX magnetic spectrometer.

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