Costa CC, Mapa LM, Kelmer AC, Ferreira SO, Bianchi RF. New insight into natural fiber-reinforced polymer composites as pressure sensors: Experiment, theory, and application. Polymer Composites [Internet]. Submitted;n/a (n/a). Publisher's VersionAbstract
Abstract Research in hybrid and flexible natural fiber-reinforced polymer composites has included advances in innovative and environmentally sustainable devices. However, in practice, controversies still exist regarding the relationship between electrical and materials performance targets in a system design context. This work aimed to investigate the alternating conductivity of a novel pressure sensor based on semiconducting polyaniline (PANI)-coated vegetable fiber (VF, Euterpe oleracea Mart., Acai) in silicone polydimethylsiloxane (PDMS) rubber. We used alternating electrical conductivity measurements, σ*(ω) ∝ ωs (frequency range—ω from 1 Hz to 10 MHz; s   0.6), to adjust the optimal operating frequency region to enhance the pressure sensing performance of the PDMS-PANI-VF composites. A generalized effective-medium approach to the pressure-induced conductivity in terms of loading pressure, percolation regime, and the interpolation between Bruggeman's symmetric and asymmetric media theories was obtained. We have found a solution for inducing percolation in composites with a low concentration of fiber inclusions by uniaxial pressure (P), characterized by the expression σ ∝ (P−P0)t (0 ≤ t ≤ 4.0, 0 ≤ P0 ≤ 250 kPa). The sensor demonstrates maximum sensitivity of 1.5 Pa−1 in the operating electrical frequency from 1 to 100 Hz, and a wide linearity range from 0 to 250 kPa. The result provides new insight into the AC universality, s, and t behaviors of natural fiber-reinforced polymer composites to enhance pressure sensitivity of a new concept and technology for resource-efficiency optimization of sustainable environmental devices.
de Araujo JFV, da Lima GS, de Almeida SA. PRESENTATION OF CONCEPTS IN A CHILDREN’S SCIENCE COMMUNICATION BOOK: THE CASE OF “ISAAC NO MUNDO DAS PARTÍCULAS”. Ensaio Pesquisa em Educação em Ciências (Belo Horizonte). 2023;25 :e39775.
Marinho JPN, Neme NP, de Matos MJS, Batista RJC, de Macedo WAA, Gastelois PL, Gomes DA, Rodrigues MA, Cipreste MF, Sousa EMB. Nanostructured system based on hydroxyapatite and curcumin: A promising candidate for osteosarcoma therapy. Ceramics International [Internet]. 2023. Publisher's VersionAbstract
Osteosarcoma is the most common type of bone cancer. Despite therapeutic progress, survival rates for metastatic cases or that do not respond well to chemotherapy remain in the 30% range. In this sense, the use of nanotechnology to develop targeted and more effective therapies is a promising tool in the fight against cancer. Nanostructured hydroxyapatite, due to its biocompatibility and the wide possibility of functionalization, is an interesting material to design nanoplatforms for targeted drug delivery. These platforms have the potential to enable the use of natural substances in the fight against cancer, such as curcumin. Curcumin is a polyphenol with promising properties in treating various types of cancer, including osteosarcoma. In this work, hydroxyapatite (n-HA) nanorods synthesized by the hydrothermal method were investigated as a carrier for curcumin. For this, first-principle calculations based on the Density Functional Theory (DFT) were performed, in which the modification of curcumin (CM) with the coupling agent (3-aminopropyl) triethoxysilane (APTES) was theoretically evaluated. Curcumin was incorporated in n-HA and the drug loading stability was evaluated by leaching test. Samples were characterized by a multi-techniques approach, including Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy (UV–Vis), X-ray diffraction (XRD), X-ray fluorescence spectrometry (FRX), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), zeta potential analysis (ζ), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results show that n-HAs with a 90 nm average size were obtained and successful incorporation of curcumin in the nanostructure was achieved. Cell viability and the number of osteosarcoma cells were decreased by CMAP-HA treatment. Furthermore, the stability test suggests that hydroxyapatite nanoparticles present great potential for the transportation of curcumin in the bloodstream, crediting this system for biological performance evaluations aiming at the treatment of osteosarcomas. Keywords: nanostructures, curcumin, hydroxyapatite, osteosarcoma.
Martins LGP, Comin R, Matos MJS, Mazzoni MSC, Neves BRA, Yankowitz M. High-pressure studies of atomically thin van der Waals materials. Applied Physics Reviews [Internet]. 2023;10 (1) :011313. Publisher's Version
Cota AB. TRANSFORMAÇÕES DE FASES EM MATERIAIS. Ouro Preto; 2023 pp. 626. Publisher's Version abcota_transformacoes_de_fases.pdf
Sousa SM, Morais HLO, Santos JCC, Barboza APM, Neves BRA, Pinto ES, Prado MC. Liquid phase exfoliation of talc: effect of the medium on flake size and shape. Beilstein Journal of Nanotechnology. 2023;14 (1) :68–78.
Leocádio RRV, Perpétuo GJ, Franco CJ, Batista AC. Growth and structural characterization of Tutton salt mixed of Co and Ni. REM-International Engineering Journal. 2023;76 :55–62.
Amarante T, Cunha THR, Laudares C, Barboza APM, dos Santos AC, Pereira CL, Ornelas V, Neves BRA, Ferlauto AS, Lacerda RG. Carbon nanotube-cellulose ink for rapid liquid identification. Beilstein Archives. 2022.
de Moraes EE, Pinto AA, Batista RJC, de Oliveira AB, Chacham H. Charge and Spin Current Rectification through Functionalized Boron Nitride Bilayers. The Journal of Physical Chemistry C [Internet]. 2022 :null. Publisher's Version
Herkenhoff Gomes A. Constraining GUP models using limits on SME coefficients. Classical and Quantum Gravity [Internet]. 2022. Publisher's VersionAbstract
Generalized uncertainty principles (GUP) and, independently, Lorentz symmetry violations are two common features in many candidate theories of quantum gravity. Despite that, the overlap between both has received limited attention so far. In this brief paper, we carry out further investigations on this topic. At the nonrelativistic level and in the realm of commutative spacetime coordinates, a large class of both isotropic and anisotropic GUP models is shown to produce signals experimentally indistinguishable from those predicted by the Standard Model Extension (SME), the common framework for studying Lorentz-violating phenomena beyond the Standard Model. This identification is used to constrain GUP models using current limits on SME coefficients. In particular, bounds on isotropic GUP models are improved by a factor of $10^7$ compared to current spectroscopic bounds and anisotropic models are constrained for the first time.
Weber CSB, Tavares A, de Araújo BB, Costa RO, Manhabosco TM, Postacchini BB, Vieira AA, Cazati T, Merlo AA. Rod-shaped cyanoacrylic derivatives with D-π-A architecture: synthesis, thermal, photophysical and theoretical studies. Liquid Crystals [Internet]. 2022 :1-11. Publisher's Version
Pinto AKM, Pontes JM, Matos MJS, Mazzoni MSC, Azevedo S. BCN diamondol-like compounds: Stability trends and electronic properties. Computational Materials Science [Internet]. 2022;215 :111737. Publisher's VersionAbstract
In this work we apply first principles calculations to investigate the stability trends of mixed boron, nitrogen and carbon diamondol-like compounds. Several distinct geometric models are tested by varying the stoichiometry and position of boron and nitrogen dopants. We verify the special stability of a complete boron nitride compound – the bonitrol –, and we show that carbon substitutions in the bonitrol structure may also lead to stable systems. The electronic characterization of the resulting compounds indicates a rich phenomenology, with metallic, semimetallic, half-metallic and semiconducting behaviors.
GOMES LL, Guimarães MHU, CRUZ LHC. A FORMAÇÃO CONTINUADA DE PROFESSORES EM TEMPOS DA PANDEMIA DO COVID-19: CONTRIBUIÇÕES DA NEUROCIÊNCIA APLICADA À EDUCAÇÃO. Formação Docente – Revista Brasileira de Pesquisa sobre Formação de Professores [Internet]. 2022;14 (30) :197–210. Publisher's Version
Rosa BLT, Fujisawa K, Santos JCC, Zhang T, Matos MJS, Sousa FB, Barbosa TC, Lafeta L, Ramos SLLM, Carvalho BR, et al. Investigation of spatially localized defects in synthetic $\mathrmWS_2$ monolayers. Phys. Rev. B [Internet]. 2022;106 :115301. Publisher's Version
Velten H, Delladea D, Primola A. Um critério energético para o desenvolvimento de vida em um exoplaneta. Cadernos de Astronomia [Internet]. 2022;3 (2) :59–65. Publisher's Version
Almeida AMR, Fabris JC, Daouda MH, Kerner R, Velten H, Hipólito-Ricaldi WS. Brans–Dicke Unimodular Gravity. Universe [Internet]. 2022;8 (8). Publisher's VersionAbstract
We propose a unimodular version of the Brans–Dicke theory designed with a constrained Lagrangian formulation. The resulting field equations are traceless. The vacuum solutions in the cosmological background reproduce the corresponding solutions of the usual Brans–Dicke theory but with a cosmological constant term. A perturbative analysis of the scalar modes is performed and stable and unstable configurations appear, in contrast with the Brans–Dicke case for which only stable configurations occur. On the other hand, tensorial modes in this theory remain the same as in the traditional Brans–Dicke theory.
Figueiredo MTD, Ferreira GMD, Lopez MAR, das Graças Cardoso M, de Oliveira JE, Bianchi RF, Ferreira GMD, Mageste AB. Immobilization of Anthocyanin in Polymeric Film to Obtain a Colorimetric Sensor for Detection of Copper in Cachaça. Food Analytical Methods. 2022 :1–19.
da Silva Lima G, de Souza LV{\'ıcio, Farias MR, Caldeira AG, de Andrade Aoyama E. CONHECIMENTO DOS ADOLESCENTES COM RELA\cCÃO ÀS INFEC\cCÕES SEXUALMENTE TRANSMISSÍVEIS. Revista Brasileira Interdisciplinar de Saúde. 2022.
da Silva FBR, Araújo FGS, von Krüger FL, Silva GJB, Batista RJC, Manhabosco T{\'ıse M. Characterization of Magnetic Tailings from Phosphate-Ore Processing in Alto Parana{\'ıba. Materials Research. 2022;25.
Franca LG, dos Santos PL, Pander P, Cabral MGB, Cristiano R, Cazati T, Monkman AP, Bock H, Eccher J. Delayed Fluorescence by Triplet–Triplet Annihilation from Columnar Liquid Crystal Films. ACS Applied Electronic Materials [Internet]. 2022 :null. Publisher's Version