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O avanço tecnológico revolucionou a prática odontológica, com os alinhadores ortodônticos emergindo como uma escolha altamente popular entre pacientes que buscam tratamentos estéticos e confortáveis. No entanto, apesar de sua crescente demanda, permanecem questões cruciais relacionadas à eficácia e análise dimensional desses dispositivos. Este artigo oferece uma análise abrangente das características químicas, físicas e mecânicas dos alinhadores ortodônticos, iluminando a influência vital do processo de termoformação e da espessura nas propriedades desses materiais. Compreender profundamente essas características é essencial para aprimorar a eficácia e a durabilidade dos alinhadores ortodônticos, contribuindo, assim, para o sucesso e a evolução dos tratamentos ortodônticos modernos. Neste estudo, exploraremos: 1) as propriedades químicas dos materiais e como elas afetam a biocompatibilidade e a resistência à degradação; 2) as características físicas, incluindo textura de superfície, transparência e sua influência na adaptação bucal e no conforto do paciente; 3) as propriedades mecânicas, como flexibilidade e rigidez, e como essas características afetam a distribuição de forças de movimentação dentária; 4) a influência do processo de termoformação na precisão e reprodutibilidade dos alinhadores, bem como sua relação com a qualidade do tratamento; 5) a análise crítica da espessura dos alinhadores e seu papel na capacidade de aplicar forças adequadas para a movimentação dentária. Ao abordar esses aspectos, este artigo visa oferecer uma visão holística das complexidades envolvidas na fabricação e uso de alinhadores ortodônticos. Esperamos que esta revisão contribua para uma compreensão mais profunda desses dispositivos e promova avanços significativos na ortodontia, beneficiando tanto os profissionais quanto os pacientes.

Technological advancement has revolutionized dental practice, with orthodontic aligners emerging as a trendy choice among patients seeking aesthetic and comfortable treatments. However, despite their growing demand, crucial questions remain regarding these devices' effectiveness and dimensional analysis. This article offers a comprehensive analysis of the chemical, physical, and mechanical characteristics of orthodontic aligners, illuminating the vital influence of the thermoforming process and thickness on the properties of these materials. Understanding these characteristics in depth is essential to improving the effectiveness and durability of orthodontic aligners, thus contributing to the success and evolution of modern orthodontic treatments. In this study, we will explore 1) the chemical properties of materials and how these properties affect biocompatibility and resistance to degradation; 2) the physical characteristics, including surface texture, transparency and their influence on oral adaptation and patient comfort; 3) mechanical properties, such as flexibility and stiffness, and how these characteristics affect the distribution of tooth movement forces; 4) the influence of the thermoforming process on the precision and reproducibility of the aligners, as well as its relationship with the quality of the treatment; 5) critical analysis of aligner thickness and its role in the ability to apply adequate forces for tooth movement. By addressing these aspects, this article aims to offer a holistic view of the complexities involved in manufacturing and using orthodontic aligners. We hope this review will contribute to a deeper understanding of these devices and promote significant advances in orthodontics, benefiting professionals and patients.

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Machine learning interatomic potentials (MLIPs) are one of the main techniques in the materials science toolbox, able to bridge ab initio accuracy with the computational efficiency of classical force fields. This allows simulations ranging from atoms, molecules, and biosystems, to solid and bulk materials, surfaces, nanomaterials, and their interfaces and complex interactions. A recent class of advanced MLIPs, which use equivariant representations and deep graph neural networks, is known as universal models. These models are proposed as foundation models suitable for any system, covering most elements from the periodic table. Current universal MLIPs (UIPs) have been trained with the largest consistent data set available nowadays. However, these are composed mostly of bulk materials' DFT calculations. In this article, we assess the universality of all openly available UIPs, namely MACE, CHGNet, and M3GNet, in a representative task of generalization: calculation of surface energies. We find that the out-of-the-box foundation models have significant shortcomings in this task, with errors correlated to the total energy of surface simulations, having an out-of-domain distance from the training data set. Our results show that while UIPs are an efficient starting point for fine-tuning specialized models, we envision the potential of increasing the coverage of the materials space toward universal training data sets for MLIPs.

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The rise in the energy demand, the need to decrease the use of fossil fuels, expanding investments in renewable energy and boosting the electric vehicle market, opens the door to new technologies in clean energy accumulators. Lithium-ion batteries are the most advanced technology in the market but have safety concerns due to the flammability of the electrolyte, which opens the door to innovations. One of these innovations is the solid-state batteries (SSB), which, by using solid electrolytes, do not have the flammable risk, bringing safety to users while reaching similar energy and power densities. This work presents a review about SSB, based on qualitative and exploratory research, using the Web of Science (WoS) platform. Keywords used to gather information from the database were "solid state batteries" and "electrolytes". Only publications from 2018 to 2023 were selected. The main research focus is to solve the challenges posed by the different physical-chemical phenomena of the SSB. This work focuses on the general comprehension of the SSB batteries, what are the factors that can affect it and the main solutions presented in the literature the last five years.

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Recent progress in natural language processing (NLP) enables mining the literature in various tasks akin to knowledge discovery. Obtaining an updated birds-eye view of key research topics and their evolution in a vast, dynamic field such as materials science is challenging even for experienced researchers. In this Perspective paper, we present a landscape of the area of applied materials in selected representative journals based on a combination of methods from network science and simple NLP strategies. We found a predominance of energy-related materials, e.g., for batteries and catalysis, organic electronics, which include flexible sensors and flexible electronics, and nanomedicine with various topics of materials used in diagnosis and therapy. As for the impact calculated through standard metrics of impact factor, energy-related materials and organic electronics are again top of the list across different journals, while work in nanomedicine has been found to have a lower impact in the journals analyzed. The adequacy of the approach to identify key research topics in materials applications was verified indirectly by comparing the topics identified in journals with diverse scopes, including journals that are not specific to materials. The approach can be employed to obtain a fast overview of a given field from the papers published in related scientific journals, which can be adapted or extended to any research area.

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O objetivo deste trabalho foi avaliar a resistência de união entre uma resina nanohíbrida para impressão 3D com cimento resinoso após diferentes tratamentos de superfície e envelhecimento. Foram fabricados 120 blocos da resina nanohíbrida (Nanolab 3D, Wilcos do Brasil) em tamanhos de 10 x 8 x 2 mm, desenhados no software Rhinoceros 7 e depois impressos (W3D PRINT, Wilcos do Brasil) por método digital de processamento de luz (LCD). Foram produzidos também blocos de mesmo tamanho obtidos a partir de blocos de CAD/CAM de uma resina híbrida (Hybrid, Blue Dent), como grupo controle. Cinco tratamentos de superfície foram realizados nos blocos de resina: nenhum tratamento, condicionamento ácido com ácido fluorídrico, jateamento com Al3O2, imersão em monômero de metilmetacrilato (primer) e um grupo somando o jateamento com imersão em primer. Foram construídos cilindros (< 1 mm2) de cimento resinoso convencional dual sobre as superfícies tratadas com auxílio de matriz de silicone. A resistência de união foi medida usando uma máquina de ensaio universal e um teste de microcisalhamento com fio. Metade das amostras de cada grupo foram testadas sete dias após a cimentação, já a outra metade foi termociclada por 12.000 ciclos térmicos (5-55 ºC, 30 segundos cada) e ensaiadas a seguir. Os modos de falha foram analisados por um estereomicroscópio e imagens representativas foram realizadas com o auxílio do microscópio eletrônico de varredura. Após a análise inferencial com ANOVA 3-fatores foi possível observar que houve diferença estatisticamente significante tanto para os fatores material, tratamento de superfície e envelhecimento isoladamente, como para as interações entre eles. A resina híbrida de impressão mostrou maior resistência de união quando comparada com os blocos CAD/CAM. A ciclagem térmica aumentou a resistência de união das resinas impressas e diminuiu a mesma nos blocos de CAD/CAM. É possível concluir que a aplicação de silano é o melhor tratamento de superfície para as resinas de impressão 3D já que proporcionou bons valores de resistência de união e confiabilidade da interface adesiva. A resistência adesiva a longo prazo da resina híbrida de impressão 3D (Nanolab) é influenciada positivamente pelo envelhecimento (AU)

The objective of this work was to evaluate the bond strength between a nanohybrid resin for 3D printing with resin cement after different surface treatments and aging. 120 blocks of nanohybrid resin (Nanolab 3D, Wilcos do Brasil) were manufactured in sizes of 10 x 8 x 2 mm, designed in the Rhinoceros 7 software and then printed (W3D PRINT, Wilcos do Brasil) by digital light processing method (LCD ). Blocks of the same size obtained from CAD/CAM blocks of a hybrid resin (Hybrid, Blue Dent) were also produced as a control group. Five surface treatments were performed on the resin blocks: no treatment, acid etching with hydrofluoric acid, sandblasting with Al3O2, immersion in methylmethacrylate monomer (primer) and one group adding the sandblasting with immersion in primer. Cylinders (< 1 mm2) of conventional dual resin cement were built on the surfaces treated with the aid of a silicone matrix. Bond strength was measured using a universal testing machine and a wire microshear test. Half of the samples from each group were tested seven days after cementation, while the other half was thermocycled through 12,000 thermal cycles (5-55 ºC, 30 seconds each) and then tested. Failure modes were analyzed using a stereomicroscope and representative images were taken using a scanning electron microscope. After the inferential analysis with 3-way ANOVA, it was possible to observe that there was a statistically significant difference both for the material, surface treatment and aging factors alone, as well as for the interactions between them. The hybrid impression resin showed higher bond strength when compared to the CAD/CAM blocks. Thermal cycling increased the bond strength of printed resins and decreased it in CAD/CAM blocks. It is possible to conclude that silane application is the best surface treatment for 3D printing resins as it provided good bond strength values and reliability of the adhesive interface. The long-term adhesive strength of the 3D printing hybrid resin (Nanolab) is positively influenced by aging. (AU)

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The discovery of carbon dots (CDs) for environmental remediation has gained awareness because of the diverse economically viable and environmental friendly green precursors generated from biowastes and biomass compared to the toxic inorganic quantum dots and CDs prepared from chemical precursors. This review presents the recent progress in green CDs, including their synthesis methods and sensing applications for the detection of heavy metal ions such as Iron (III), Mercury (II), Copper (II), Chromium (VI), Lead (II), Arsenic (III), Cobalt (II), Aluminum (III), Silver (I), and Gold (III) which are prominent environmental pollutants. The comparison based on selectivity, sensitivity, quantum yield, detection limit, linear concentration range, and sensing mechanisms are also reported. This review also covers the performance of doped green CDs using heteroatoms, toward the detection of heavy metal ions. Apart from the future perspectives, this review provides a general guide to use such environmental friendly CDs to detect harmful pollutants.

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Introduction: This study aims to analyze the influence of particles size of sol-gel derived calcium silicate particles in the setting reaction of bioactive endodontic cements. Materials and Methods: Sol-gel derived calcium silicate particles were synthesized and sieved to separate the particles in different sizes: CS400, CS200, and CS100. A commercial MTA (Control) was used as control. The particle size and the specific surface area were assessed by laser diffraction and nitrogen adsorption. The cements were prepared with water as the liquid for the reaction. The setting time was conducted according to ISO 6876, and the setting kinetics was analyzed by Fourier trans-formed infrared spectroscopy (FTIR) at different time points between 120s to 72h. Results: The particle size varied from 9.45µm (CS400 ) to 31.01 (Control). The higher specific surface area valuer reached 15.14g/cm2 in the CS400. The smallest particle sizes, the higher specific surface area, and the lowest setting time were found for CS400 (p < 0.05). Control presented the highest setting time (p < 0.05). The FTIR analyses showed the differences in materials structure over time, with faster hydration and crystallization for CS400. The setting kinetics was slower for Control even when compared to a sol-gel derived group with similar particle size. Conclusion:The route of synthesis and the particle size influences the setting reaction of calcium silicate-based cements. The reduction of particle size for sol-gel derived calcium silicates lead to the acceleration of the setting reaction of the produced bioactive endodontic cement.

Introdução: Este estudo tem como objetivo analisar a influência do tamanho de partículas de silicato de cálcio derivadas de sol-gel na reação de presa de cimentos endodônticos bioativos. Materiais e Métodos: Partículas de silicato de cálcio derivadas de sol-gel foram sintetizadas e peneiradas para separar as partículas em diferentes tamanhos: CS400, CS200 e CS100. Um MTA comercial (Controle) foi usado como controle. O tamanho das partículas e a área superficial específica foram avaliados por difração a laser e adsorção de nitrogênio. Os cimentos foram preparados com água como líquido para a reação. O tempo de presa foi conduzido de acordo com a ISO 6876, e a cinética de presa foi analisada por espectroscopia de infravermelho transformada de Fourier (FTIR) em diferentes pontos de tempo entre 120s a 72h. Resultados: O tamanho de partícula variou entre 9,45µm (CS400) e 31,01 (Controle). A maior área de superfície foi encontrada nas partículas do grupo CS400 (15.14g/cm2). Os menores tamanhos de partícula, a maior área de superfície específica e o menor tempo de presa foram encontrados para CS400 (p < 0,05). O Control apresentou o maior tempo de presa (p < 0,05). As análises de FTIR mostraram as diferenças na estrutura dos materiais ao longo do tempo, com hidratação e cristalização mais rápidas para CS400. A cinética de presa foi mais lenta para Control mesmo quando comparado a um grupo derivado de sol-gel com tamanho de partícula semelhante. Conclusão: A rota de síntese e o tamanho das partículas influenciam a reação de endurecimento dos cimentos à base de silicato de cálcio. A redução do tamanho de partícula para silicatos de cálcio derivados de sol-gel leva à aceleração da reação de pega do cimento endodôntico bioativo produzido.

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Introduction: Metal organic frameworks (MOFs) are a recent group of nano porous materials with exceptional physical properties, such as large surface areas, high pore volumes, low densities and well-defined pores. This type of material has been used frequently for biomedical and therapeutic applications, such as drug delivery systems and theranostic materials.Areas covered: In this review, the authors searched for patents filed in the last 10 years, found in different databases, related to the therapeutic or biomedical application of MOFs for use in different health fields. The possibility of these new materials becoming new therapeutic possibilities available to the population was emphasized.Expert opinion: The advances in research with MOFs have grown in the last 10 years and with that many possibilities for their applications have emerged in several areas, especially biomedical. The possibility of using these materials in drug delivery systems is the most common form of possibility of use in the health area, mainly due to easy obtaining and high reproducibility, which are seen very positively by the drug development technology sector.

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PURPOSE: The purpose of this study was to study the influence of high-pressure (HP) polymerization on the mechanical properties of denture base PMMA resins compared with conventional thermopolymerization and PMMA discs for digital dentures. MATERIALS AND METHODS: Three groups of blocks were prepared: Probase Hot (Ivoclar Vivadent, Lichtenstein) conventionally heat polymerized at 100°C, Probase Hot heat polymerized at 100°C under HP (200 MPa) and Ivobase CAD (Ivoclar Vivadent, Lichtenstein). Samples for mechanical/physical (n = 30) and samples for viscoelastic (n = 10) characterizations were cut from the blocks. Flexural strength (σf ), elastic modulus (Ef ), hardness, density (ρ), flexural deformation at maximal flexural stress, flexural load energy (Ur ) and viscoelastic properties (E', E'', Tanδ, Tg ) were analyzed using one-way ANOVA (α = 0.05), Scheffé multiple means comparisons (α = 0.05) and Weibull statistics (for σf ). SEM images of the fractured surfaces were obtained. RESULTS: Ef , E', E'' and density of HP polymerized Probase hot were significantly higher than conventional heat polymerized Probase Hot, whereas Tg was significantly lower and σf , Tanδ, hardness, flexural deformation at maximal flexural stress, Ur were not significantly different. The highest values for σf , flexural deformation at maximal flexural stress, Ur and Weibull modulus were obtained with Ivobase CAD. CONCLUSION: HP polymerization does not significantly increase the mechanical properties of denture base resins.

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Some physical properties of spider silks, including mechanical strength and toughness, have been studied in many laboratories worldwide. Given that this silk is organic in nature, composed of protein, and has similar properties to metal wires or polymers, it has the potential for application in medicine, nanoelectronics, and other related areas. In this study, we worked on spider silk from the Nephila clavipes species collected from the wild and kept it in the nursery of the Autonomous University of the West, Cali, Colombia, to determine its physical, thermal, and mechanical properties, seeking possible applications in the medical and industrial sectors and comparing the material properties of the silk from the species from southwestern Colombia with those of the previously studied species from other regions. The mechanical characterization of the material was performed using a universal testing machine; thermal behavior was captured by a thermogravimetric analysis, differential scanning calorimetry, and mass spectrometry; and structural characterization was performed using diffraction X-rays. The results of the thermal characterization demonstrate that the spider silk loses 10 % of water content at 150 °C with significant changes at 400 °C, while the mechanical characterization indicates that the spider silk is much tougher than Kevlar 49 and Nylon 6 since it is capable of absorbing more energy before rupture.

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Pyrolysis techniques provide an interesting way of recycling plastic wastes (PW) by transforming them into liquid fuels with high calorific values. Catalysts are employed in PW pyrolysis in order to favor cracking reactions; in that regard, cheap and abundant natural resources are being investigated as potential catalyst precursors. This article explores the pyrolysis of low-density polyethylene (LDPE) in a semibatch reactor under a reduced pressure of 300 torr and temperatures in the range of 370 °C-430 °C. Three different solid materials, an activated carbon (AC1), a commercial Fluid cracking catalyst (FCC) and an aluminum- pillared clay (Al-PILC), were tested as catalysts for the pyrolysis process. Thermogravimetric analyzes were previously performed to select the most catalytically active materials. AC1 displayed very low catalytic activity while FCC and Al-PILC displayed high activity and conversion to liquid products. Hydrocarbons ranging from C5 to C28 were identified in the liquid products as well as significant changes in their composition when FCC and Al-PILC catalyst were used. Differences in the catalytic activity of the 3 solid materials are ascribed mainly to differences in their acid properties.

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Effects of high hydrostatic pressure (HHP) processing (200-400 MPa/5 or 10 min) on functional properties of cellulose acetate (CA) films were investigated. As for mechanical properties, HHP caused a reduction in tensile strength (TS), Young's modulus (YM) and an increase in elongation at break (EB). The pressurized films were more luminous, yellowish, reddish and opaque. Less affinity for water was detected for pressurized films through analyses of contact angle and moisture absorption, in addition to reducing the water vapor transmission rate (WVTR). Scanning electron microscopy (SEM) showed the occurrence of delamination for most films, except those treated with 200 MPa/10 min and 300 MPa/10 min. All films showed a predominance of amorphous structure in X-ray diffraction analysis (XRD). That is alignment with the results of differential scanning calorimetry (DSC), which presented values for glass transition temperature (Tg), water adsorption and melting temperature characteristic of materials with low crystallinity. Films treated with HHP had better mechanical resistance during the sealing at 250 °C. In overall the results confirmed the minimal influence of HHP on the functional properties of the CA film and contributed to the scientific and technological knowledge for its potential application in foods processed by HHP.

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OBJECTIVES: Development of a new generation of stable ß alloy, free of aluminum or vanadium and with better biological and mechanical compatibility and evaluate the surface properties of Ti-6Al-4V and Ti-35Nb-7Zr-5Ta after anodization in hydrofluoric acid, followed by deposition of different electrolyte concentrations of magnesium particles by micro arc-oxidation treatment. METHODS: Disks were anodized in hydrofluoric acid. After this first anodization, the specimens received the deposition of magnesium using different concentration (8.5% and 12.5%) and times (30s and 60s). The surface morphology was assessed using scanning electron microscopy, and the chemical composition was assessed using energy dispersive x ray spectroscopy. The surface free energy was measured from the contact angle, and the mean roughness was measured using a digital profilometer. RESULTS: Anodization in hydrofluoric acid provided the formation of nanotubes in both alloys, and the best concentration of magnesium considered was 8.5%, as it was the condition where the magnesium was incorporated without covering the morphology of the nanotubes. X-ray dispersive energy spectroscopy showed magnesium incorporation in all conditions. The average roughness was increased in the Ti-35Nb-7Zr-5Ta alloy. CONCLUSIONS: It was concluded that anodizing could be used to deposit magnesium on the surfaces of Ti-6Al-4V and Ti-35Nb-7Zr-5Ta nanotubes, with better results obtained in samples with magnesium concentration in 8.5% and the process favored the roughness in the Ti-35Nb-7Zr-5Ta group.

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Films and edible coatings based on biopolymers have been developed as a packaging, which can be obtained from biodegradable materials and have properties similar to common plastics. These edible materials have many applications in the food industry, preventing mass transfer between the product and the surrounding environment. The objective of this study was to develop and evaluate the physicochemical and mechanical properties of edible films based on cassava starch (CS), whey protein (WP), and beeswax (BW). Response surface methodology has been used and the experiments were carried out based on face-centred composite design. On the other hand, three CS-based controls were formulated to evaluate the effect of the inclusion of WP and BW. The optimization of multiple responses established the optimal formulation: CS (3.17 %), WP (1.30 %), BW (0.50 %), presenting the following response variables: tensile stress (1.92 MPa), elongation (40.4 %), Young's modulus (42.1 MPa), water vapor permeability 1.79 × 10-11 (g mm/s cm2 Pa), swelling capacity (300.3 %), thickness (0.128 mm), moisture content (6.74 %), and colour: lightness (89.9), chromaticity a∗ (-1.8), chromaticity b∗ (7.7), saturation (9.9), tone (101.1°), and yellowness index (17.7). The selection and evaluation of this optimal formulation are essential because it is the material that shows the best possible mechanical and physicochemical properties using the studied components. The results, especially its good mechanical properties and low permeability to water vapour, would allow its application as a coating for fruits, vegetables, among others, effectively delaying its weight loss due to dehydration.

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Baked foams made with plantain flour (PF) and sugarcane fiber (SF) were characterized by calorimetric, mechanical, physicochemical and structural techniques in order to assess the results induced by different sugarcane concentrations and fiber size on the structure of baked foams. The addition of SF to the baked samples increased their hydrophobic properties. Thermal conductivity (TC) decreased when the concentration of SF was 10 g and 7.5 g in the baked foams. The density of the biodegradable baked foams (BBFs) decreased with decreasing concentrations of SF, observing an inverse behavior in water vapor permeability (WVP) and solubility properties. The mechanical properties of the baked foams were more influenced by the concentration of SF than by the size of SF, obtained from different sieves. The scanning electron microscopy cross-sectional images of the BBFs showed that the size of SF affected the size and number of the internal cells in the BBFs.

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The composition changes in the close to surface of the austenitic stainless steel DIN 1.4981 irradiated at high doses. Theoretical simulations using the SRIM-2013 program show that the damage due to Nickel cation [Ni2+] ions irradiation of 3.66 MeV extends to up 2 µm deep in the steel under study. Then the applications of Grazing incidence X-ray Diffraction (GXRD) and X-ray Photoelectron Spectroscopy (XPS), Gallium cation [Ga3+] ions sputtering assisted, were necessary to detect respectively, any compositional changes with the depth. GXRD differences were recorded in the intensity and it's Full Width at Half Maximum (FWHM), of the austenite (111) diffraction peak, at different depths in the Irradiate Zone (IZ). Through XPS was found that Nickel [Ni], Niobium [Nb], and Manganese [Mn] were depleted it is important to highlight Chromium [Cr], and Molybdenum [Mo] were improved at the irradiated surface; such behavior was contrary to the element migration under irradiation reported for austenitic stainless steels irradiated at low doses.

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PVDF was prepared by compression molding, and its phase content/structure was assessed by WAXD, DSC, and FTIR-ATR spectroscopy. Next, PVDF samples were aged in bioethanol fuel at 60 °C or annealed in the same temperature by 30 ─ 180 days. Then, the influence of aging/annealing on thermal stability, thermal degradation kinetics, and lifetime of the PVDF was investigated by thermogravimetric analysis (TGA/DTG), as well as the structure was again examined. The crystallinity of ~41% (from WAXD) or ~49% (from DSC) were identified for unaged PVDF, without significant changes after aging or annealing. This PVDF presented not only one phase, but a mixture of α-, ß- and γ-phases, α- and ß-phases with more highlighted vibrational bands. Thermal degradation kinetics was evaluated using the non-isothermal Ozawa-Flynn-Wall method. The activation energy (E a ) of thermal degradation was calculated for conversion levels of α = 5 ─ 50% at constant heating rates (5, 10, 20, and 40 °C min─1), α = 10% was fixed for lifetime estimation. The results indicated that temperature alone does not affect the material, but its combination with bioethanol reduced the onset temperature and E a of primary thermal degradation. Additionally, the material lifetime decreased until about five decades (T f = 25 °C and 90 days of exposition) due to the fluid effect after aging.

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BACKGROUND: Biofunctionalization of titanium surfaces can improve host responses, especially considering the time for osteointegration and patient recovery. This prompted us to modify titanium surfaces with alendronate and albumin and to investigate the behavior of osteoblasts on these surfaces. METHODS: The biofunctionalization of titanium surfaces was characterized using classical physicochemical approaches and later used to challenge pre-osteoblast cells up to 24 h. Then their viability and molecular behavior were investigated using mitochondrial dehydrogenase activity and RTq-PCR technologies, respectively. Potential stimulus of extracellular remodeling was also investigated by zymography. RESULTS: Our data indicates a differential behavior of cells responding to the surfaces, considering the activity of mitochondrial dehydrogenases. Molecularly, the differential expression of genes related with cell adhesion highlighted the importance of Integrin-ß1, Fak, and Src. These 3 genes were significantly decreased in response to titanium surfaces modified with alendronate, but this behavior was reverted when alendronate was associated with albumin. Alendronate-modified surfaces promoted a significant increase on ECM remodeling, as well as culminating with greater gene activity related to the osteogenic phenotype (Runx2, Alp, Bsp). CONCLUSION: Altogether, our study found interesting osteogenic behavior of cells in response to alendronate and albumin surfaces, which indicates the need for in vivo analyses to better consider these surfaces before clinical trials within the biomedical field.

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OBJECTIVES: The present study examined a technique for reducing dentin permeability through the application of a calcium phosphate (CaP)-based desensitiser with a laser-assisted process and evaluated adhesive-dentin bond strength. Methods: Thirty dentin discs were divided into two groups according to whether the selected desensitiser (TeethMate; Kuraray Noritake) was used prior to dentin bonding. Each group was subdivided into three subgroups (n = 5): A- Adhesive (Single Bond Universal, 3M ESPE), AL- Adhesive + Laser (Nd:YAG 60 mJ) and LAL- Laser + Adhesive + Laser. Dentin permeability values (%) were recorded before and after desensitiser application. Resin composites were placed over the bonded specimens; the latter were aged prior to microtensile bond strength evaluation. Gelatinolytic activity within the hybrid layers was examined with in-situ zymography using confocal laser scanning microscopy. Data were analysed with ANOVA and Tukey test (α = 0.05). RESULTS: Significant differences in dentin permeability were identified for all groups (p = 0.00). Both laser treatment (p = 0.182) and desensitiser application (p = 0.687) did not significantly improve dentin bond strength. Ultrastructure of the resin-dentin interface identified presence of calcium phosphate within dentinal tubules. Laser treatment did not affect hybrid layer ultrastructure. Both treatment modalities (intratubular CaP occlusion and laser) had no influence on gelatinolytic activity within hybrid layers. CONCLUSION: Although intratubular CaP occlusion and laser treatment were effective in reducing dentin permeability, they did not affect bond strength, interfacial ultrastructure and gelatinolytic activity within hybrid layers. CLINICAL RELEVANCE: Treatment of etched dentin with Nd:YAG Laser at 60 mJ does not adversely affect collagen ultrastructure and gelatinolytic activity within the hybrid layer. The application of a calcium phosphate-based desensitiser to etch dentin does not affect dentin bond strength.

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Food packaging materials are commonly derived from petroleum that increases global contamination; this raises the interest to evaluate raw material from renewable sources such as whey protein for the development of packaging materials, especially to produce active films. This research aimed to evaluate whey protein-based film properties when natamycin, nanoemulsioned α-tocopherol, or both were added. An oil-in-water (O/W) nanoemulsion of antioxidant (α-tocopherol) was prepared by microfluidization technique. Four films were prepared with different levels of natamycin and nanoemulsified α-tocopherol and were characterized in terms of physicochemical, mechanical, optical-properties, water vapor barrier, FTIR, microstructure, antioxidant and antimicrobial activity. The natamycin, nanoemulsified α-tocopherol, or both did not modify the moisture content of the films. Moreover lead to a significant reduction of tensile strength and elastic modulus, while presenting growth in the elongation at break. Film opacity, the total color difference, the UV-Vis light barrier, and the water vapor permeability values increased when compounds were incorporated into the film. The microstructure studies showed uniformly distributed porosity throughout the films. The addition of nanoemulsioned α-tocopherol into whey protein-based films provoked antioxidant activity and the addition of natamycin produced films with effectivity against C. albicans, P. chrysogenum, and S. cerevisiae, allowing develop a material appropriate for use as active food packaging.