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  • ItemArtigo
    Gold conjugated-magnetite nanoparticles for magnetic concentration towards reproducibility and repeatability of SERS measurements
    (2023-08-20) Miyazaki, Celina M. [UNESP]; Martin, Cibely S. [UNESP]; Constantino, Carlos J.L. [UNESP]; Universidade Estadual Paulista (UNESP)
    Variables such as uncontrolled colloid aggregation, and even the natural motion of particles named Brownian motion, lead to small variations in the molecular position and arrangement between molecule and nanoparticles, thus influencing SERS magnitude. To address this issue, we synthesized gold conjugated-magnetic nanoparticles (AuMNP) as a SERS platform for dopamine (DA) detection. Unlike conventional colloids such as silver and gold, which are unable to provide SERS for DA, the AuMNP not only yielded SERS signal but also improved repeatability and reproducibility. Under a magnetic concentration using a neodymium magnet, the standard deviation of ten measurements was found to be 19.4 versus 800 (arb.un.) for the magnetically concentrated and dispersion measurements, respectively. The hot spots formation in the AuMNP and the possible DA − AuMNP interactions are in the origin of the obtained SERS signal. Additionally, the DA SERS signal varied with concentration according to the Freundlich isotherm model, indicating multilayer adsorption. The limit of detection was in order of 10–6 mol/L without further optimizations.
  • ItemArtigo
    Characterization of Eco-Friendly Self-Standing Films Based on Cashew Nut Shell Liquid and Polyaniline
    (2023-08-01) Aguiar, Francílio Vieira; Amorim, Daniel Roger Bezerra; Bandeira, Rafael Marinho; da Silva Guimarães, Iran; Job, Aldo Eloizo [UNESP]; Agostini, Deuber [UNESP]; Vega, Maria Leticia; da Cunha, Helder Nunes; Ciência e Tecnologia do Piauí; UFPI – Universidade Federal do Piauí; IFMA – Instituto Federal do Maranhão; Universidade Estadual Paulista (UNESP)
    In this work, structural, spectroscopic, and electrical characterizations of self-standing films comprising polyaniline (PANI) and a natural eco-friendly material, cashew nut shell liquid (t-CNSL), were carried out. The films were studied by atomic force microscopy (AFM), infrared spectroscopy (FTIR), thermal analyses (TGA), dynamic mechanical analyses (DMA), X-ray diffraction (XRD), and electrical impedance spectroscopy. The wt.% of t-CNSL in the films varied from 0 to 60%. The 3D images from AFM revealed a significant increase in the roughness of the films at high concentrations as a result of weak chemical interactions between the PANI and t-CNSL. The FTIR data indicate that chemical interaction between PANI/t-CNSL might be occurring possibly due to a second doping mechanism caused by t-CNSL in the film. TGA analyses showed that the addition of t-CNSL improves the thermal stability of the films. From the DMA results, we observed a small decrease of the glass transition temperature as t-CNSL is incorporated into the films. XRD diffractogram indicates slight variations in the arrangement of molecules/chains of the films due to the t-CNSL. The electrical measurements showed that films containing more than 10% of t-CNSL exhibit superior conductivity in comparison to neat PANI films in particular for 50% of t-CNSL in which the conductivity reaches the maximum value. These results show that t-CNSL acts as both plasticizer and dopant agent in PANI-based films, providing an environmentally friendly way to increase the conductivity on blending PANI.
  • ItemArtigo
    Leishmanicidal Activity of Guanidine Derivatives against Leishmania infantum
    (2023-03-01) Almeida, Fernanda Silva; Moreira, Vitor Partite [UNESP]; Silva, Edson dos Santos; Cardoso, Leonardo Lima; de Sousa Palmeira, Pedro Henrique; Cavalcante-Silva, Luiz Henrique Agra; Araújo, Demétrius A. M. de; Amaral, Ian P. G. do; González, Eduardo René Pérez [UNESP]; Keesen, Tatjana S. L.; Federal University of Paraiba; Universidade Federal da Paraíba (UFPB); Universidade Estadual Paulista (UNESP)
    Leishmaniasis is a neglected tropical infectious disease with thousands of cases annually; it is of great concern to global health, particularly the most severe form, visceral leishmaniasis. Visceral leishmaniasis treatments are minimal and have severe adverse effects. As guanidine-bearing compounds have shown antimicrobial activity, we analyzed the cytotoxic effects of several guanidine-bearing compounds on Leishmania infantum in their promastigote and amastigote forms in vitro, their cytotoxicity in human cells, and their impact on reactive nitrogen species production. LQOFG-2, LQOFG-6, and LQOFG-7 had IC50 values of 12.7, 24.4, and 23.6 µM, respectively, in promastigotes. These compounds exhibited cytotoxicity in axenic amastigotes at 26.1, 21.1, and 18.6 µM, respectively. The compounds showed no apparent cytotoxicity in cells from healthy donors. To identify mechanisms of action, we evaluated cell death processes by annexin V and propidium iodide staining and nitrite production. Guanidine-containing compounds caused a significant percentage of death by apoptosis in amastigotes. Independent of L. infantum infection, LQOFG-7 increased nitrite production in peripheral blood mononuclear cells, which suggests a potential mechanism of action for this compound. Therefore, these data suggest that guanidine derivatives are potential anti-microbial molecules, and further research is needed to fully understand their mechanism of action, especially in anti-leishmanial studies.
  • ItemArtigo
    Biosynthesis of silver nanoparticles of Tribulus terrestris food supplement and evaluated antioxidant activity and collagenase, elastase and tyrosinase enzyme inhibition: In vitro and in silico approaches
    (2023-03-01) Figueiredo, Célia Cristina Malaguti [UNESP]; da Costa Gomes, Amanda [UNESP]; Zibordi, Laura Camargo [UNESP]; Granero, Filipe Oliveira [UNESP]; Ximenes, Valdecir Farias [UNESP]; Pavan, Nathalia Mariana [UNESP]; Silva, Luciana Pereira; Sonvesso, Cibely da Silva Martin [UNESP]; Job, Aldo Eloizo [UNESP]; Nicolau-Junior, Nilson; Silva, Regildo Márcio Gonçalves da [UNESP]; Universidade Estadual Paulista (UNESP); Fundação Educacional do Município de Assis (FEMA); Universidade Federal de Uberlândia (UFU)
    Food supplements from plants are source of many antioxidant substances. Tribulus terrestris food supplement (TtFS) is highlighted as one of these supplements that has presented potential to prevent damages and diseases caused by oxidative stress. In addition, new formulations that enhance the benefits of food supplement have been developed and metallic nanoparticles, the so-called green synthesis, has been of great interest. UV–visible spectroscopy, energy dispersive spectroscopy (EDS), Zeta potential (ZP), scanning transmission electron microscopy (STEM), scanning electron microscope (SEM) were used to characterize the synthesized silver nanoparticles (AgNPs). Antioxidant activity was determined by DPPH radical scavenging, ferric ion reducing power (FRAP); ABTS radical scavenging, and oxygen radical absorption capacity (ORAC-FL). Molecular docking analyses were performed to evaluate molecular interactions. Antioxidant evaluation of TtFS demonstrated 83.6% antioxidant activity (DPPH), 714.82 μM Trolox Equivalent (TE)/g sample (FRAP), 91.24 μM TE/g sample (ABTS), and antioxidant activity in ORAC assay. It presented inhibition activity on collagenase (75.33%), elastase (54.04%) and tyrosinase (59.07%). In addition, in silico assays showed an interaction between T. terrestris steroidal saponins and DNA, and the highest DNA binding affinity was observed with protodioscin. Steroidal saponins also presented interaction with all enzymes evaluated. The characterization of AgNPs demonstrated that they were formed as a spherical shape. These AgNPs showed greater protective properties against oxidative stress (85.41% antioxidant activity (DPPH) and 957.55 μM TE/g sample (FRAP)). The results represent an important indicator for the development and discovery of new nanoestructured pharmaceutical and cosmetic formulation using plants and natural products.
  • ItemArtigo
    Effects of resistance exercise training on bone physical and mineral properties in rats submitted to growth hormone intervention
    (2023-01-01) Castoldi, Robson Chacon [UNESP]; Giometti, Ines Cristina; Ozaki, Guilherme Akio Tamura [UNESP]; Garcia, Thiago Alves [UNESP]; dos Santos Pereira, João Domingos Augusto [UNESP]; Rubira, Rafael Jesus Gonçalves [UNESP]; Constantino, Carlos José Leopoldo [UNESP]; de Oliveira Júnior, Silvio Assis; Louzada, Mario Jefferson Quirino; Belangero, William Dias; Silva Camargo Filho, José Carlos [UNESP]; Universidade Estadual Paulista (UNESP); Universidade do Oeste Paulista – UNOESTE; Universidade Federal de Mato Grosso do Sul (UFMS); Catholic Salesian Auxilium University Centre; Universidade Estadual de Campinas (UNICAMP)
    Purpose: To investigate the effects of applying growth hormone (GH) and performing a strength training protocol on mineralization, rigidity, and crystallinity on the bone tissue of Wistar rats. Method: In total, 40 male animals, 60 days old, of the Wistar lineage were used, distributed into four groups: control (C) [n = 10], control and application of GH (GHC) [n = 10], resistance training (T) [n = 10], and resistance training and application of GH (GHT) [n = 10]. The training period lasted four weeks and consisted of four sets of 10 jumps in a liquid medium. The amount of 0.2 IU per kilogram of body mass (0.2 IU/Kg) of GH was administered in the GHC and GHT groups. After the experimental period, samples of the tibia were collected and analyzed using Raman Spectroscopy (633 nm), Bone Densitometry - dual-energy x-ray absorptiometry (DXA), and Mechanical Assay (F-max). Results: The GHT group presented an increase for the variable Amide II (1544 cm-1) and decrease for the variable Proline (727 cm-1) from the Raman Spectroscopy analysis (p < 0.05). In addition, an increase was observed for the variables bone mineral density (BMD) and bone mineral content (BMC) (p < 0.05). Finally, no statistically significant differences were observed for the variables mineralization, crystallinity, phosphate carbonate types A and B, and bone rigidity (p > 0.05). Conclusion: It is concluded that GH added to RT resulted in an increase in the mineral Amide II (1544 cm-1) and a decrease in Proline (727 cm-1). Furthermore, an increase in BMD and BMC was observed only in the GHT group. Finally, no alterations were observed in crystallinity and rigidity in the different groups of animals.
  • ItemArtigo
    The invasive Egeria densa macrophyte and its potential as a new renewable energy source: A study of degradation kinetics and thermodynamic parameters
    (2023-01-15) de Azevedo, Claudia Gonçalves [UNESP]; dos Santos, Renivaldo José [UNESP]; Hiranobe, Carlos Toshiyuki [UNESP]; Zanette, Andréia Fátima [UNESP]; Job, Aldo Eloizo [UNESP]; Silva, Michael Jones [UNESP]; Universidade Estadual Paulista (UNESP)
    The increase in global demand, along with environmental concerns, has led to the need for new sources that can supply the energy needed for socioeconomic development while reducing pollutant emissions. Aquatic biomasses, especially those of invasive aquatic macrophytes, can be potential energy sources, and this study evaluated the thermal degradation of the invasive Egeria densa macrophytes (EDM) in an inert environment at four heating rates to evaluate its potential as a low-cost biomass and bioenergy source. Pyrolysis experiments were performed using a thermogravimetric analyzer. The thermal profile of invasive EDM has three main events (multiple stages). Stages (i) and (ii) occur at a temperature range of 125–395 °C and represent the decomposition of carbohydrates such as hemicellulose and cellulose. Stage (iii) occurs between 395 and 500 °C and mainly relates to the decomposition of lignin. Thermal data have been used to analyze kinetic parameters through isoconversional methods, and the activation energy (Ea) value of EDM showed variation at different conversion points. The highest Ea values were observed for conversion rates of 0.3–0.6 due to the increased energy required to break down the lignocellulosic chains during decomposition. The small difference between the enthalpy change and Ea values for the different isoconversional methods can be due to a small potential energy barrier, which reflects the feasibility that the reaction can occur under the expected conditions. Gibbs free energy (137–145 kJ mol−1) and high heating value (13.40 MJ/kg) revealed a significant bioenergy potential for EDM biomass.
  • ItemArtigo
    Effects of replacing Carbon Black with Wood Fibers in wood-rubber composites
    (2023-01-01) Raia, Renan Zunta; Iwakiri, Setsuo; Trianoski, Rosilani; de Andrade, Alan Sulato; Kowalski, Edemir Luiz; Job, Aldo Eloizo [UNESP]; de Paiva, Fábio Friol Guedes; Universidade Federal do Paraná (UFPR); Universidade Estadual Paulista (UNESP); Universidade do Oeste Paulista – UNOESTE
    The objective of this research was to develop a more sustainable composite and still keep its characteristics. Fibers treated with NaOH at 5% w/w for 2 hours were incorporated into natural rubber in different proportions (0 phr, 24 phr, 36 phr, 48 phr and 60 phr). The mechanical properties of the composites suffered changes, increasing the hardness, young’s modulus and decreasing its tensile strength. All the physical properties were not statistically different. The coloration became less dark in the WF60/CB0 treatment, and the electrical properties presented better resistivity with the increase in the concentration of fibers in the composite. This presents a possibility of using WF for the production of wood-rubber composites for the production of rubber artifacts which do not require high rolling resistance. Based on the results from this research, we recommended the WF24/CB36 mix to produce antistatic floors.
  • ItemArtigo
    Recycling waste polyurethane from the refrigeration industry as filler in SBR/NR composites for industrial applications
    (2023-04-10) Hiranobe, Carlos Toshiyuki [UNESP]; Tolosa, Gabrieli Roefero [UNESP]; de Almeida Santos, Gleyson Tadeu [UNESP]; de Oliveira, João Pedro Jenson; Budemberg, Eduardo Roque [UNESP]; da Silva, Michael Jones [UNESP]; Cabrera, Flávio Camargo [UNESP]; Job, Aldo Eloizo [UNESP]; Paim, Leonardo Lataro [UNESP]; Torres, Giovanni Barrera; dos Santos, Renivaldo José [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Estadual de Campinas (UNICAMP); Instituto Tecnológico Metropolitano (ITM)
    The refrigeration industry produces millions of tons of waste polyurethane (PU) every year, which can cause environmental damage and human health problems. This article analyzes the use of waste PU as filler in composites made of styrene butadiene rubber (SBR) and natural rubber (NR) to produce shoe soles. The interfacial interaction of said filler was evaluated by the Flory–Rehner method (swelling) using the equation developed by Lorenz–Park. The results of this evaluation were later compared with those obtained by the Mooney–Rivlin method using the data from stress–strain tests. According to the results of the tensile strength tests, the composites filled with waste PU present stress–strain curves that are like those of metallic materials that have low elastic strength but high plastic strength. Using the Lorenz–Park equation, the filled composites examined in this study exhibited values above 0.7, which means a strong filler–rubber interaction. Scanning Electron Microscopy and Fourier-Transform Infrared Spectroscopy were used to investigate the morphology of the composites in detail.
  • ItemArtigo
    Immobilization and Application of the Recombinant Xylanase GH10 of Malbranchea pulchella in the Production of Xylooligosaccharides from Hydrothermal Liquor of the Eucalyptus (Eucalyptus grandis) Wood Chips
    (2022-11-01) Alnoch, Robson C.; Alves, Gabriela S.; Salgado, Jose C. S.; de Andrades, Diandra; Freitas, Emanuelle N. de; Nogueira, Karoline M. V.; Vici, Ana C.; Oliveira, Douglas P. [UNESP]; Carvalho-Jr, Valdemiro P. [UNESP]; Silva, Roberto N.; Buckeridge, Marcos S.; Michelin, Michele; Teixeira, José A.; Polizeli, Maria de Lourdes T. M.; Universidade de São Paulo (USP); Universidade Estadual Paulista (UNESP); University of Minho
    Xylooligosaccharides (XOS) are widely used in the food industry as prebiotic components. XOS with high purity are required for practical prebiotic function and other biological benefits, such as antioxidant and inflammatory properties. In this work, we immobilized the recombinant endo-1,4-β-xylanase of Malbranchea pulchella (MpXyn10) in various chemical supports and evaluated its potential to produce xylooligosaccharides (XOS) from hydrothermal liquor of eucalyptus wood chips. Values >90% of immobilization yields were achieved from amino-activated supports for 120 min. The highest recovery values were found on Purolite (142%) and MANAE-MpXyn10 (137%) derivatives, which maintained more than 90% residual activity for 24 h at 70 °C, while the free-MpXyn10 maintained only 11%. In addition, active MpXyn10 derivatives were stable in the range of pH 4.0–6.0 and the presence of the furfural and HMF compounds. MpXyn10 derivatives were tested to produce XOS from xylan of various sources. Maximum values were observed for birchwood xylan at 8.6 mg mL−1 and wheat arabinoxylan at 8.9 mg mL−1, using Purolite-MpXyn10. Its derivative was also successfully applied in the hydrolysis of soluble xylan present in hydrothermal liquor, with 0.9 mg mL−1 of XOS after 3 h at 50 °C. This derivative maintained more than 80% XOS yield after six cycles of the assay. The results obtained provide a basis for the application of immobilized MpXyn10 to produce XOS with high purity and other high-value-added products in the lignocellulosic biorefinery field.
  • ItemArtigo
    Physical-Mechanical Properties of Chartwell® Coupling Agent-Treated Calcium Carbonate and Silica-Reinforced Hybrid Natural Rubber Composites
    (2022-11-01) Ribeiro, Gabriel Deltrejo [UNESP]; Hiranobe, Carlos Toshiyuki [UNESP]; da Silva, José Francisco Resende [UNESP]; Torres, Giovanni Barrera; Paim, Leonardo Lataro [UNESP]; Job, Aldo Eloizo [UNESP]; Cabrera, Flávio Camargo [UNESP]; dos Santos, Renivaldo José [UNESP]; Universidade Estadual Paulista (UNESP); Instituto Tecnológico Metropolitano (ITM)
    In this work investigated the possibility of applying a superficial treatment to ultra-fine calcium carbonate aiming to improve its interaction with the polymer chains of natural rubber so it does not act just as a filler. Commercial processes commonly use 40 phr of Silica as reinforcement filler. Here, we have evaluated the partial replacement of Silica by two types of calcium carbonate into hybrid natural rubber composites, untreated ultra-fine calcium carbonate and with ultra-fine calcium carbonate treated with 2% Chartwell C-515.71HR®. We added calcium carbonate fillers to the composite mixtures (as replacements for commercial silica treated with silane) and studied their influence on the vulcanization process. According to our findings, between 25% and 75% of the silica can be replaced with treated calcium carbonate, and up to 30 parts of CaCO3 can be combined with 100 parts of NR without compromising the properties of the polymer matrix (NR), which generates economic advantages for this industry. Treated calcium carbonate was able to link the inorganic and organic parts of the composite due to its bifunctionality; hence, it can be used as a filler to partially replace silica in hybrid NR composites.
  • ItemArtigo
    Use of Charcoal and Partially Pirolysed Biomaterial in Fly Ash to Produce Briquettes: Sugarcane Bagasse
    (Intechopen, 2011-01-01) Teixeira, Silvio Rainho [UNESP]; Souza, Agda Eunice de [UNESP]; Vilche Pena, Angel Fidel [UNESP]; Lima, Regiane Godoy de [UNESP]; Miguel, Alvaro Gil; Manzanera, M.; Universidade Estadual Paulista (UNESP); Usina Alto Alegre
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    Nanoparticle Technology: an alternative approach for Leishmaniasis Treatment
    (Intech Europe, 2014-01-01) Job, Aldo Eloizo [UNESP]; Siqueira, Alexandre Fioravante de [UNESP]; Danna, Caroline Silva [UNESP]; Bellucci, Felipe Silva [UNESP]; Cabrera, Flavio Camargo [UNESP]; Kerche Silva, Leandra Ernst [UNESP]; Benites Aoki, Pedro Henrique [UNESP]; Claborn, D. M.; Universidade Estadual Paulista (UNESP)
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    Utilization of Composites and Nanocomposites Based on Natural Rubber and Ceramic Nanoparticles as Control Agents for Leishmania braziliensis
    (Intech Europe, 2014-01-01) Job, Aldo Eloizo [UNESP]; Siqueira, Alexandre Fioravante de [UNESP]; Danna, Caroline Silva [UNESP]; Bellucci, Felipe Silva [UNESP]; Cabrera, Flvio Camargo [UNESP]; Kerche Silva, Leandra Ernst [UNESP]; Claborn, D. M.; Universidade Estadual Paulista (UNESP)
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    Plasmonics in Analytical Spectroscopy
    (Amer Chemical Soc, 2015-01-01) Aoki, Pedro H. B. [UNESP]; Constantino, Carlos J. L. [UNESP]; Oliveira, Osvaldo N.; Aroca, Ricardo F. [UNESP]; Wang, C.; Leblanc, R. M.; Universidade Estadual Paulista (UNESP); Universidade de São Paulo (USP)
    Surface plasmon resonances (SPR) can be excited in thin metal films and in metal nanoparticles as localized surface plasmon resonances (LSPR). The surface plasmon is extremely sensitive to the refractive index of the environment surrounding the metal film or metal nanoparticle. This is why refractive index sensing has been the source for the development of an array of techniques harnessing the power of both SPR and LSPR. In addition, LSPR is at the center of plasmon enhanced spectroscopy with a myriad of analytical applications. Here we examine the basic physical model of plasmon enhancement, with the intention of facilitating the design of plasmonic nanostructures and experiments, taking advantage of these emerging techniques. In particular, we discuss the plasmon enhanced work based on shell-isolated nanoparticles (SHINs) in Raman scattering (SHINERS) and in fluorescence (SHINEF). Typical examples have been selected to illustrate the physical interpretation of observations.
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    Plasmon-Enhanced Scattering and Fluorescence Used for Ultrasensitive Detection in Langmuir- Blodgett Monolayers
    (Blackwell Science Publ, 2014-01-01) Volpati, Diogo [UNESP]; Alsaleh, Aisha; Constantino, Carlos J. L. [UNESP]; Aroca, Ricardo; Ozaki, Y.; Kneipp, K.; Aroca, R.; Universidade Estadual Paulista (UNESP); Univ Windsor
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    Applications of Natural Rubber Composites and Nanocomposites
    (Royal Soc Chemistry, 2014-01-01) Job, Aldo E. [UNESP]; Cabrera, Flavio C. [UNESP]; Salmazo, Leandra O. [UNESP]; Rodriguez-Perez, Miguel A.; Lopez Gil, Alberto; Siqueira, Alexandre F. de [UNESP]; Bellucci, Felipe S. [UNESP]; Thomas, S.; Maria, H. J.; Joy, J.; Chan, C. H.; Pothen, L. A.; Universidade Estadual Paulista (UNESP); Univ Valladolid UVA
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    Magnetic Filler-Reinforced Natural Rubber Macro- and Nanocomposites
    (Royal Soc Chemistry, 2014-01-01) Job, Aldo Eloizo [UNESP]; Bellucci, Felipe Silva [UNESP]; Cabrera, Flavio Camargo [UNESP]; Siqueira, Alexandre Fioravante de [UNESP]; Budemberg, Eduardo Roque; Salmazo, Leandra Oliveira [UNESP]; Thomas, S.; Maria, H. J.; Joy, J.; Chan, C. H.; Pothen, L. A.; Universidade Estadual Paulista (UNESP); Universidade de São Paulo (USP)
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    Manganese oxides synthesized via microwave-assisted hydrothermal method: phase evolution and structure refinement
    (2022-01-01) Neto, Roumanos Georges Dib [UNESP]; Macedo, Wagner Costa [UNESP]; Fernandes, José Diego [UNESP]; de Souza, Agda Eunice [UNESP]; Teixeira, Silvio Rainho [UNESP]; Rocha, Kleper de Oliveira [UNESP]; Longo, Elson; Universidade Estadual Paulista (UNESP); Universidade Federal de São Carlos (UFSCar)
    Manganese oxides were synthesized during 40 min at 140 ºC via Microwave-Assisted Hydrothermal (MAH) method and treated at different temperatures in order to evaluate the phase evolution using structure refinement (Rietveld method). The samples obtained were heat treated at temperatures defined by means of thermal analysis (160 ºC, 480 ºC, 715 ºC, 870 ºC, 920 ºC and 1150 ºC) and analyzed by X-Ray Diffractometry (XRD), X-Ray Fluorescence (XRF), Fourier Transform Infrared (FTIR) spectroscopy, Raman scattering, UV-Vis absorption and Scanning Electron Microscopy (SEM). Structural characterizations allowed to identify five distinct phases: α-MnO2, Mn3 O4, Mn5 O8, Na2 Mn5 O10 and Na4 Mn9 O18 with weight percentages dependent on the heat treatment. The hausmannite structure (average crystallite size ranging from 28.9 nm to 99.1 nm) is present in all samples and go through various oxidation and reduction processes from 160 ºC to 1150 ºC without any major variation in the lattice parameters. Chemical characterizations identifies the presence of Na+ ions in all samples, either as substitution defects or as components of specific crystalline structures (Na2 Mn5 O10 and Na4 Mn9 O18), showing that the synthesized manganese oxides works as Na+ intercalation compounds, important materials for energy storage devices optimization. The results presented enables a better interpretation of the thermal and structural characteristics of manganese oxides synthesized via MAH.
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    Analysis of the effects of curcumin and symbiotic consumption on bones of rats submitted to the use of dexamethasone
    (2022-09-01) de Oliveira, Julia Aparecida Galdino Torralba; Neves, Mariana Daudt; Sampaio, Gleicy Fernanda Soares; Constantino, Carlos José Leopoldo [UNESP]; Nakagaki, Wilson Romero; University of Western São Paulo (UNOESTE); Universidade Estadual Paulista (UNESP)
    Aims: Glucocorticoids have adverse side effects that can compromise bone tissue. There is evidence to show that symbiotics and curcumin can prevent bone loss. The aim of this study was to analyze the effects of curcumin and symbiotic to prevent and/or minimize a possible bone impairment in rats submitted to the use of dexamethasone. Methods: Fifty Wistar female rats were divided into five groups: control group (CT), dexamethasone control group (D), dexamethasone and symbiotic group (DS), dexamethasone and curcumin group (DC), and dexamethasone and symbiotic/curcumin group (DSC). Dexamethasone was applied three times a week, while the symbiotic and curcumin were administered daily. Alkaline phosphatase and calcium dosages, analysis of structural and material properties, and Raman analysis of femurs were performed. Key findings: Alkaline phosphatase was higher in the DC group. Maximum load and structural stiffness were higher in the CT group. Maximum stress was lower and similar between dexamethasone groups. The CT group had a lower percentage of strain, the D group had greater deformation compared to the DC group and the DS group presented more deformation than the DC group. The D, DS, and DSC groups had a lower elastic modulus compared to the CT group. The 960/1660 ratios of the D, DS, and DSC groups were different from the CT group. The 1070/1660 ratio was higher in the DC group. Significance: It was possible to verify that curcumin showed promising effects related to the increase in bone strength and mineralization, mitigating the deleterious effects caused by dexamethasone, when used simultaneously with this drug.
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    Chemical treatment of sugarcane bagasse and its influence on glyphosate adsorption
    (2022-01-01) Da Penha Bezerra, Williene Faria [UNESP]; Dognani, Guilherme [UNESP]; De Alencar, Laura Neves [UNESP]; Parizi, Marcela Prado Silva [UNESP]; Boina, Rosane Freire [UNESP]; Cabrera, Flávio Camargo; Job, Aldo Eloízo [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Estadual de Maringá (UEM)
    Due to the production rates of sugarcane, nowadays, the sugarcane bagasse stemming in the sugar and alcohol industry is the agro-industrial waste produced in greater volume throughout in Brazil. In 2019, about 192 million tons of this waste were generated. The use of this waste has been the aim of researches around the world, with emphasis on applications that aim to meet the prerogatives of the concept of circular economy. Within this scenario, sugarcane bagasse (SB) was treated in an alkaline medium, forming an adsorbent material, SBNaOH. The effects of chemical treatment were evaluated for surface properties and for glyphosate removal in an aqueous medium. The adsorptive phenomenon was studied through isotherm tests. The results obtained were fitted to classical models of Langmuir, Freundlich and Dubinin-Radushkevich. The characterization indicated that the chemical treatment promoted an important change in the surface of the residue, increasing the surface area. SB and SBNAOH had a feasible behavior as adsorbent and good performance in the removal of the herbicide, presenting values greater than 65% of under all working conditions. The theoretical adsorption saturation governed by Dubinin-Radushkevich (qS) was in the order of 8.988 mg/g (R2=0.988) for SB at 120 minutes of contact and maximum adsorption capacity by Langmuir (Qmax) was 13.720 mg/g (R2=0.984) for SBNaOH at 40 minutes of contact. The process was governed by the exchange or sharing of electrons. The adsorbate is distributed heterogeneously on the SB surface, justifying the presence of active sites with greater ionic strength, and homogeneously on the SBNaOH surface (monolayer). In general, the treated sugarcane bagasse, coming from an agro-industrial residue, proved to be an alternative and promising biosorbent for the removal of glyphosate from aqueous systems, thus generating a new application of this residue.