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Objetivamos contribuir com a análise dos dez anos de DCN para a Educação Física no sentido de compreender o que este processo nos proporcionou e ainda nos proporciona. Para isso, iremos relacionar DCN e Formação, mediados pelas categorias de Legalidade, Conhecimento e Mundo/Mercado de trabalho. Utilizamos a dialética materialista como método de análise e pesquisa bibliográfica, e a análise documental como técnica de pesquisa. Por fim, considerando que os desafios continuam, entendemos que avaliar os resultados deste processo e tomar posição sobre ele coincide com avaliar e tomar posição sobre a própria área da Educação Física em sua totalidade.

This study aimed to evaluate the environmental impact of dental materials: commercial composite Tetric EvoCeram®, glass ionomer Equia Forte® HT Fil, laboratory-prepared composite, alkasite Cention® Forte, amalgam Amalcap® Plus, and samples from dental chair drainage systems (DCDS). Methacrylate monomers were detected in the eluates of experimental and commercials composites, and alkasite. In DCDS samples solely mercury was found at concentrations of 0.08-1.86 μg/L. The experimental composite (48 h incubation) exhibited the highest toxicity on zebrafish Danio rerio (LC 50 =0.70 g/L), followed by amalgam (LC 50 =8.27 g/L) < Tetric EvoCeram® (LC 50 =10.94 g/L) < Equia Forte® HT Fil (LC 50 =24.84 g/L) < Cention® Forte (LC 50 =32.22 g/L). Exposure of zebrafish to DCDS samples resulted in decreased larval body length and increased occurrences of edema and blood accumulation. The results obtained highlight the need for additional monitoring and further research on the release of unreacted monomers and mercury from dental materials and their environmental impact., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Plastic pollution in aquatic ecosystems has become a significant problem especially microplastics which can encapsulate into the skeletons of organisms that produce calcium carbonates, such as foraminifera, molluscs and corals. The encapsulation of microplastics into precipitated aragonite, which in nature builds the coral skeleton, has not yet been studied. It is also not known how the dissolved organic matter, to which microplastics are constantly exposed in aquatic ecosystems, affects the encapsulation of microplastics into aragonite and how such microplastics affect the mechanical properties of aragonite. We performed aragonite precipitation experiments in artificial seawater in the presence of polystyrene (PS) and polyethylene (PE) microspheres, untreated and treated with humic acid (HA). The results showed that the efficiency of encapsulating PE and PE-HA microspheres in aragonite was higher than that for PS and PS-HA microspheres. The mechanical properties of resulting aragonite changed after the encapsulation of microplastic particles. A decrease in the hardness and indentation modulus of the aragonite samples was observed, and the most substantial effect occurred in the case of PE-HA microspheres encapsulation. These findings raise concerns about possible changes in the mechanical properties of the exoskeleton and endoskeleton of calcifying marine organisms such as corals and molluscs due to the incorporation of pristine microplastics and microplastics exposed to dissolved organic matter.

Magnetite nanoparticles (NPs) possess properties that make them suitable for a wide range of applications. In recent years, interest in the synthesis of magnetite NPs and their surface functionalization has increased significantly, especially regarding their application in biomedicine such as for controlled and targeted drug delivery. There are several conventional methods for preparing magnetite NPs, all of which mostly utilize Fe(iii) and Fe(ii) salt precursors. In this study, we present a microwave hydrothermal synthesis for the precipitation of magnetite NPs at temperatures of 200 °C for 20 min and 260 °C for 5 min, with only iron(iii) as a precursor utilizing chamomile flower extract as a stabilizing, capping, and reducing agent. Products were characterized using FTIR, PXRD, SEM, and magnetometry. Our analysis revealed significant differences in the properties of magnetite NPs prepared with this approach, and the conventional two-precursor hydrothermal microwave method (sample MagH). FTIR and PXRD analyses confirmed coated magnetite particles. The temperature and magnetic-field dependence of magnetization indicate their superparamagnetic behavior. Importantly, the results of our study show the noticeable cytotoxicity of coated magnetite NPs-toxic to carcinoma cells but harmless to healthy cells-further emphasizing the potential of these NPs for biomedical applications.

Debye temperatures of α -Sn x Fe 1- x OOH nanoparticles ( x = 0, 0.05, 0.10, 0.15 and 0.20, abbreviated as Sn100 x NPs) prepared by hydrothermal reaction were estimated with 57 Fe- and 119 Sn-Mössbauer spectra measured by varying the temperature from 20 to 300 K. Electrical properties were studied by solid-state impedance spectroscopy (SS-IS). Together, the charge-discharge capacity of Li- and Na-ion batteries containing Sn100 x NPs as a cathode were evaluated. 57 Fe-Mössbauer spectra of Sn10, Sn15, and Sn20 measured at 300 K showed only one doublet due to the superparamagnetic doublet, while the doublet decomposed into a sextet due to goethite at the temperature below 50 K for Sn 10, 200 K for Sn15, and 100 K for Sn20. These results suggest that Sn10, Sn15 and Sn20 had smaller particles than Sn0. On the other hand, 20 K 119 Sn-Mössbauer spectra of Sn15 were composed of a paramagnetic doublet with an isomer shift ( δ ) of 0.24 mm s -1 and quadrupole splitting (∆) of 3.52 mm s -1 . These values were larger than those of Sn10 ( δ : 0.08 mm s -1 , ∆: 0.00 mm s -1 ) and Sn20 ( δ : 0.10 mm s -1 , ∆: 0.00 mm s -1 ), suggesting that the Sn IV -O chemical bond is shorter and the distortion of octahedral SnO 6 is larger in Sn15 than in Sn10 and Sn20 due to the increase in the covalency and polarization of the Sn IV -O chemical bond. Debye temperatures determined from 57 Fe-Mössbauer spectra measured at the low temperature were 210 K, 228 K, and 250 K for Sn10, Sn15, and Sn20, while that of α -Fe 2 O 3 was 324 K. Similarly, the Debye temperature of 199, 251, and 269 K for Sn10, Sn15, and Sn20 were estimated from the temperature-dependent 119 Sn-Mössbauer spectra, which were significantly smaller than that of BaSnO 3 (=658 K) and SnO 2 (=382 K). These results suggest that Fe and Sn are a weakly bound lattice in goethite NPs with low crystallinity. Modification of NPs and addition of Sn has a positive effect, resulting in an increase in DC conductivity of almost 5 orders of magnitude, from a σ DC value of 9.37 × 10 -7 (Ω cm) -1 for pure goethite Sn (Sn0) up to DC plateau for samples containing 0.15 and 0.20 Sn (Sn15 and Sn20) with a DC value of ~4 × 10 -7 (Ω cm) -1 @423 K. This non-linear conductivity pattern and levelling at a higher Sn content suggests that structural modifications have a notable impact on electron transport, which is primarily governed by the thermally activated via three-dimensional hopping of small polarons (SPH). Measurements of SIB performance, including the Sn100 x cathode under a current density of 50 mA g -1 , showed initial capacities of 81 and 85 mAh g -1 for Sn0 and Sn15, which were larger than the others. The large initial capacities were measured at a current density of 5 mA g -1 found at 170 and 182 mAh g -1 for Sn15 and Sn20, respectively. It is concluded that tin-goethite NPs are an excellent material for a secondary battery cathode and that Sn15 is the best cathode among the studied Sn100 x NPs.

The present study investigates the relationship between the local structure, photocatalytic ability, and cathode performances in sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs) using Ni-substituted goethite nanoparticles (Ni x Fe 1-x OOH NPs) with a range of 'x' values from 0 to 0.5. The structural characterization was performed applying various techniques, including X-ray diffractometry (XRD); thermogravimetry differential thermal analysis (TG-DTA); Fourier transform infrared spectroscopy (FT-IR); X-ray absorption spectroscopy (XANES/EXAFS), both measured at room temperature (RT); 57 Fe Mössbauer spectroscopy recorded at RT and low temperatures (LT) from 20 K to 300 K; Brunauer-Emmett-Teller surface area measurement (BET), and diffuse reflectance spectroscopy (DRS). In addition, the electrical properties of Ni x Fe 1-x OOH NPs were evaluated by solid-state impedance spectroscopy (SS-IS). XRD showed the presence of goethite as the only crystalline phase in prepared samples with x ≤ 0.20, and goethite and α-Ni(OH) 2 in the samples with x > 0.20. The sample with x = 0.10 (Ni10) showed the highest photo-Fenton ability with a first-order rate constant value ( k ) of 15.8 × 10 -3 min -1 . The 57 Fe Mössbauer spectrum of Ni0, measured at RT, displayed a sextet corresponding to goethite, with an isomer shift ( δ ) of 0.36 mm s -1 and a hyperfine magnetic distribution ( B hf ) of 32.95 T. Moreover, the DC conductivity decreased from 5.52 × 10 -10 to 5.30 × 10 -12 (Ω cm) -1 , attributed to its largest specific surface area of 174.0 m -1 , attributed to its largest specific surface area of 174.0 m 2 g -1 . In conclusion, Ni x Fe 1-x OOH NPs can be effectively utilized as visible-light-activated catalysts and active cathode materials in secondary batteries.

In this study, we present a new approach for the synthesis of Pt/SnO 2 catalysts using microwave radiation. Pt(IV) and Sn(IV) inorganic precursors (H 2 PtCl 6 and SnCl 4 ) and ammonia were used, which allowed the controlled formation of platinum particles on the anisotropic SnO 2 support. The synthesized Pt/SnO 2 samples are mesoporous and exhibit a reversible physisorption isotherm of type IV. The XRD patterns confirmed the presence of platinum maxima in all Pt/SnO 2 samples. The Williamson-Hall diagram showed SnO 2 anisotropy with crystallite sizes of ~10 nm along the c-axis (< 00l >) and ~5 nm along the a-axis (< h00 >). SEM analysis revealed anisotropic, urchin-like SnO 2 particles. XPS results indicated relatively low average oxidation states of platinum, close to Pt metal. 119 Sn Mössbauer spectroscopy indicated electronic interactions between Pt and SnO 2 particles. The synthesized samples were used for the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of excess NaBH 4 . The catalytic activity of the Pt/SnO 2 samples for the reduction of 4-NP to 4-AP was optimized by varying the synthesis parameters and Pt loading. The optimal platinum loading for the reduction of 4-NP to 4-AP on the anisotropic SnO 2 support is 5 mol% with an apparent rate constant k = 0.59 × 10 -2 s -1 . The Pt/SnO 2 sample showed exceptional reusability and retained an efficiency of 81.4% after ten cycles.

Nanostructured cemented carbides with Co binders have shown excellent mechanical properties in various applications. Nevertheless, their corrosion resistance has shown to be insufficient in different corrosive environments, leading to premature tool failure. In this study, WC-based cemented carbide samples with different binders were produced using 9 wt% of FeNi or FeNiCo with the addition of Cr 3 C 2 and NbC as the grain growth inhibitors. The samples were investigated using electrochemical corrosion techniques: the open circuit potential E corr , the linear polarization resistance (LPR), the Tafel extrapolation method, and the electrochemical impedance spectroscopy (EIS) at room temperature in the solution of 3.5% NaCl. Microstructure characterization, surface texture analysis, and instrumented indentation were conducted to investigate the influence of corrosion on the micro-mechanical properties and the surface characteristics of the samples before and after corrosion. The obtained results indicate a strong binder chemical composition's effect on the consolidated materials' corrosive behavior. Compared to the conventional WC-Co systems, a significantly improved corrosion resistance was observed for both alternative binder systems. The study shows that the samples with the FeNi binder are superior to those with the FeNiCo binder since they were almost unaffected when exposed to the acidic medium.

The adsorption of the antibiotic ciprofloxacin (CIP) from water solution by natural zeolite-clinoptilolite (CLI), magnetic clinoptilolite (MAG-CLI), and graphene oxide coated magnetic clinoptilolite (GO-MAG-CLI) was investigated. The novel approach of an environmentally friendly and cost-effective microwave-assisted method was applied for the magnetic composite synthesis. Detailed characterization of the prepared composites was achieved. In order to investigate the effect of the initial CIP concentration, pH, temperature, contact time, and type of adsorbent on the adsorption efficiency of CIP, and to obtain the optimal conditions for CIP removal, the response surface methodology central composite factorial design (RSM-CCF) was applied. The results obtained by the RSM-CCF showed that among the studied adsorbents, GO-MAG-CLI had the highest adsorption capacity for CIP, achieved for the initial concentration of 48.47 mg dm -3 at a pH of 5 and 24.78 °C after 19.20 min of contact time. The adsorption kinetics studied for the initial CIP concentration range of 15-50 mg dm -3 followed Lagergren's pseudo-second-order model, and the Langmuir isotherm was the most suitable one to describe the CIP adsorption onto GO-MAG-CLI.

Background: The directionality analysis of the neurite outgrowths is an important methodology in neuroscience, especially in determining the behavior of neurons grown on silicon substrates., New Method: Here we aimed to describe the methodology for quantification of the directionality of neurites based on the Fast Fourier Transform (FFT). We performed an image analysis case study that incorporates several software solutions and provides a rapid and precise technique to determine the directionality of neurites. In order to elicit aligned or unaligned neurite growth patterns, we used adult and newborn dorsal root ganglion (DRG) neurons grown on silicon micro-pillar substrates (MPS) with different pillar widths and spacing., Results: Compared to the control glass surfaces the neonatal and adult N52 and IB4 DRG neurites exhibited regular growth patterns more pronounced in the MPS regions with s narrow pillar spacing range. The neurites were preferentially oriented along three directional axes at 30°, 90°, and 150°., Conclusion: The proposed methodology showed that FFT analysis is a reliable and easily reproducible method that can be successfully used to test growth patterns of DRG neurites grown on different substrates by considering the direction and angle of the neurites as well as the size of the soma., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Morphine (MORPH) is natural alkaloid and mainly used as a pain reliever. Its monitoring in human body fluids is crucial for modern medicine. In this paper, we have developed an electrochemical sensor for submicromolar detection of MORPH. The sensor is based on modified carbon paste electrode (CPE) by investigating the Fe x W 1-x O 4 ratio in iron tungstate (FeWO 4 ), as well as the ratio of this material in CPE. For the first time, the effect of the iron-tungsten ratio in terms of achieving the best possible electrochemical characteristics for the detection of an important molecule for humans was examined. Morphological and electrochemical characteristics of materials were studied. The best results were obtained using Fe 1 W 3 and 7.5% of modifier in CPE. For MORPH detection, square wave voltammetry (SWV) was optimized. Under the optimized conditions, Fe 1 W 3 @CPE resulted in limit of detection (LOD) of the method of 0.58 µM and limit of quantification (LOQ) of 1.94 µM. The linear operating range between 5 and 85 µM of MORPH in the Britton-Robinson buffer solution (BRBS) at pH 8 as supporting electrolyte was obtained. The Fe 1 W 3 @CPE sensor resulted in good selectivity and excellent repeatability with relative standard deviation (RSD) and was applied in real-world samples of human urine. Application for direct MORPH detection, without tedious sample pretreatment procedures, suggests that developed electrochemical sensor has appeared to be a suitable competitor for efficient, precise, and accurate monitoring of the MORPH in biological fluids.

With the growing number of flexible electronics applications, environmentally benign ways of mass-producing graphene electronics are sought. In this study, we present a scalable mechanochemical route for the exfoliation of graphite in a planetary ball mill with melamine to form melamine-intercalated graphene nanosheets (M-GNS). M-GNS morphology was evaluated, revealing small particles, down to 14 nm in diameter and 0.4 nm thick. The M-GNS were used as a functional material in the formulation of an inkjet-printable conductive ink, based on green solvents: water, ethanol, and ethylene glycol. The ink satisfied restrictions regarding stability and nanoparticle size; in addition, it was successfully inkjet printed on plastic sheets. Thermal and photonic post-print processing were evaluated as a means of reducing the electrical resistance of the printed features. Minimal sheet resistance values (5 kΩ/sq for 10 printed layers and 626 Ω/sq for 20 printed layers) were obtained on polyimide sheets, after thermal annealing for 1 h at 400 °C and a subsequent single intense pulsed light flash. Lastly, a proof-of-concept simple flexible printed circuit consisting of a battery-powered LED was realized. The demonstrated approach presents an environmentally friendly alternative to mass-producing graphene-based printed flexible electronics.

The solid-state ion-selective electrodes presented here are based on the FePO 4 :Ag 2 S:polytetrafluoroethylene (PTFE) = 1:1:2 with an addition of (0.25-1)% microwave-synthesized hematite (α-Fe 2 O 3 ), magnetite (Fe 3 O 4 ), boehmite [γ-AlO(OH)], and alumina (Al 2 O 3 ) nanoparticles (NPs) in order to establish ideal membrane composition for iron(III) cations determination. Synthesized NPs are characterized with Fourier-Transform Infrared (FTIR) spectroscopy, Powder X-Ray Diffraction (PXRD), and Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy (EDS). The iron oxides NPs, more specifically, magnetite and hematite, showed a more positive effect on the sensing properties than boehmite and alumina NPs. The hematite NPs had the most significant effect on the linear range for the determination of ferric cations. The membrane containing 0.25% hematite NPs showed a slope of -19.75 mV per decade in the linear range from 1.2∙10 -6 to 10 -2 mol L -1 , with a correlation factor of 0.9925. The recoveries for the determination of ferric cations in standard solutions were 99.4, 106.7, 93.6, and 101.1% for different concentrations.

Red mud (RM) contains large quantities of microscale particles < 1 μm and high concentrations of potentially toxic elements. In this research, we have used two types of RM of similar chemical properties but containing different quantities of micro-particles, to test whether their size plays a role in the uptake of chemical elements by earthworm Eisenia fetida. Earthworms were exposed for seven days to artificial soils (prepared in the laboratory following a protocol) amended with increasing quantities of RM. Mortality of 86 % occurred when earthworms were exposed to amended soil containing 46 % of particles below 1 μm. Surprisingly, tissue analyses have shown decreased concentrations of metals instead of the expected toxic effect. SEM analysis revealed that micro-particles strongly adhere to the earthworm epidermis putting them under the large stress. Micro-particles in RM clog their minute dermal pores of 90 nm-735 nm in diameter, which size depends on whether the earthworm's body is contracted or stretched. Strong adhesion of micro-particles to earthworms' epidermis and blockage of their microsize pores prevented normal dermal respiration and absorption of chemical elements through their epithelium resulting in a decrease of most measured metals, especially essential elements potassium, calcium and iron, followed by the lethal outcomes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Microporous and macro-mesoporous silicon templates for surface-enhanced Raman scattering (SERS) substrates were produced by anodization of low doped p-type silicon wafers. By immersion plating in AgNO3, the templates were covered with silver metallic film consisting of different silver nanostructures. Scanning electron microscopy (SEM) micrographs of these SERS substrates showed diverse morphology with significant difference in an average size and size distribution of silver nanoparticles. Ultraviolet-visible-near-infrared (UV-Vis-NIR) reflection spectroscopy showed plasmonic absorption at 398 and 469 nm, which is in accordance with the SEM findings. The activity of the SERS substrates was tested using rhodamine 6G (R6G) dye molecules and 514.5 nm laser excitation. Contrary to the microporous silicon template, the SERS substrate prepared from macro-mesoporous silicon template showed significantly broader size distribution of irregular silver nanoparticles as well as localized surface plasmon resonance closer to excitation laser wavelength. Such silver morphology has high SERS sensitivity that enables ultralow concentration detection of R6G dye molecules up to 10(-15) M. To our knowledge, this is the lowest concentration detected of R6G dye molecules on porous silicon-based SERS substrates, which might even indicate possible single molecule detection.