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OBJECTIVES: This study evaluated the impact of different solvents and UV post-curing times on properties of 3D printing resins for provisional restorations. METHODS: The post-processing methods were tested using two solvents (isopropyl alcohol or absolute ethanol) and three UV times (5, 10, or 30 min). The resins tested were Resilab 3D Temp, Printax Temp, and Prizma Bioprov. Microhardness (kgf/mm2), fracture toughness (KIC, MPa√m), surface roughness (Ra, µm), gloss (gloss units), and degree of CC conversion (%DC) were measured (n = 8). All response variables were collected from the same specimen. The specimens were 3D printed using an SLA/LCD printer (150° angulation, 50 µm layer thickness). Light exposure times were adjusted for each material, and the post-processing methods were applied using an all-in-one machine immediately after printing. Data were analyzed using Three-Way ANOVA (α = 0.05). RESULTS: Microhardness was affected by UV post-cure time and 3D resin. Resilab showed higher microhardness with isopropyl alcohol and 30-min UV time, while Printax had higher microhardness with absolute ethanol. KIC was influenced by solvent type, UV time, and 3D resin, with varying effects on different resins. Roughness was affected by 3D resin and UV time, but no significant differences were seen for Resilab or Prizma. Gloss was influenced by 3D resin, and for Prizma, it was lower with specific solvent/UV time combinations. DC was influenced by 3D resin, with each resin behaving differently. SIGNIFICANCE: Tailoring the combination of 3D resin, solvent washing type, and UV post-curing time is important to achieve optimal mechanical and aesthetic outcomes for restorations.

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Structural health monitoring (SHM) is vital to ensuring the integrity of people and structures during earthquakes, especially considering the catastrophic consequences that could be registered in countries within the Pacific ring of fire, such as Ecuador. This work reviews the technologies, architectures, data processing techniques, damage identification techniques, and challenges in state-of-the-art results with SHM system applications. These studies use several data processing techniques such as the wavelet transform, the fast Fourier transform, the Kalman filter, and different technologies such as the Internet of Things (IoT) and machine learning. The results of this review highlight the effectiveness of systems aiming to be cost-effective and wireless, where sensors based on microelectromechanical systems (MEMS) are standard. However, despite the advancement of technology, these face challenges such as optimization of energy resources, computational resources, and complying with the characteristic of real-time processing.

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As características geométricas e técnicas de fabricação das limas endodônticas afetam o desempenho clínico e sua resistência à fratura, flexibilidade e outras propriedades. Um parâmetro muito explorado na Endodontia é a utilização de tratamentos térmicos, que promovem um aumento na resistência à fadiga e flexibilidade destes materiais. Neste estudo pretendeu-se avaliar o efeito de diferentes processos de tratamento térmico/usinagem nas propriedades físicas, flexibilidade, resistência torcional e à fadiga flexural dos instrumentos Prodesign Logic (PDL), verificando se a sequência de processamento dos instrumentos levaria a comportamentos mecânicos diferentes. Este sistema é fabricado a partir de um método inovador que envolve a realização do tratamento térmico para obtenção de memória de forma no fio NiTi anteriormente à usinagem. A hipótese nula a ser testada é que o momento de aplicação dos procedimentos de tratamento térmico e usinagem não afetariam as propriedades físicas e mecânicas de instrumentos endodônticos de NiTi. Para grupos de comparação, foram utilizados protótipos de instrumentos com as mesmas características geométricas e dimensionais, sendo um grupo de instrumentos sem tratamento térmico aplicado (SEP) e outro com o tratamento térmico realizado de forma convencional, após a usinagem do instrumento (HTP). Foram realizadas caracterização física e microestrutural com ensaios de calorimetria exploratória diferencial (DSC) e testes de difratometria de Raios-X (DRX), além de ensaios mecânicos divididos em testes de torção, dobramento em 45 e resistência à fadiga flexural. Os resultados mostraram que macroscopicamente não houve nenhuma alteração importante nas características dos três grupos de instrumentos, exceto mudanças de cor devido a diferentes sequências de processamento. Os resultados de DSC mostraram que à temperatura ambiente a liga é principalmente austenítica no grupo SEP e que após o tratamento térmico realizado nos grupos PDL e HTP, houve uma mudança nas temperaturas de transformação, com um aumento da temperatura de Af e predominância da liga NiTi em fase R. Os resultados de XDR confirmaram os achados do DSC. As diferenças nos parâmetros medidos entre diferentes tipos de instrumentos nos ensaios de resistência torcional, dobramento a 45º e fadiga flexural foi sempre considerada com um nível de significância de 95%. Os resultados para os ensaios de flexão mostraram que o grupo HTP mostrou-se o mais flexível, com os mais baixos valores de momento de dobramento, seguido por PDL e SEP. Nos resultados dos ensaios de torção foi possível observar que SEP apresentou valores mais altos de torque seguido por PDL e HTP (p<.05). Os ensaios de resistência à fadiga mostraram valores médios de NCF maiores para HTP, seguido por PDL e SEP. Entretanto, um pior comportamento do PDL só seria evidenciado clinicamente se os instrumentos fossem usados um número de vezes maior do que o recomendado pelo fabricante. Pode-se concluir que alterar o processo de fabricação dos instrumentos endodônticos, invertendo-se as etapas de usinagem e tratamento térmico, levou, de fato, a uma mudança no comportamento mecânico de instrumentos Prodesign Logic em relação aos prótótipos.

The geometric characteristics and manufacturing techniques of endodontic instruments affect clinical performance, fracture resistance, flexibility and other properties. A parameter widely explored in Endodontics is the use of heat treatments, which promote an increase in the resistance to fatigue and flexibility of these materials. This study aimed to evaluate the effect of different heat treatment / machining processes on the physical properties, flexibility, torsional strength and flexural fatigue of Prodesign Logic (PDL) instruments, verifying whether the processing sequence of the instruments would lead to different mechanical behaviors. This system is manufactured using an innovative method that involves performing thermal treatment to obtain shape memory in the NiTi wire prior to machining. The null hypothesis to be tested is that the moment of application of the heat treatment and machining procedures would not affect the physical and mechanical properties of NiTi endodontic instruments. For comparison groups, instrument prototypes with the same geometric and dimensional characteristics were used, being one group of instruments without thermal treatment applied (SEP) and another with thermal treatment carried out in a conventional manner, after machining the instrument (HTP). Physical and microstructural characterization were performed with differential scanning calorimetry (DSC) tests and X-ray diffractometry (XRD) tests, in addition to mechanical tests divided into torsion tests, 45° bending and resistance to flexural fatigue. The results showed that macroscopically there were no major change in the characteristics of the three groups of instruments, except for color changes due to different processing sequences. The DSC results showed that at room temperature the alloy is mainly austenitic in the SEP group and that after the heat treatment carried out in the PDL and HTP groups, there was a change in the transformation temperatures, with an increase in the Af temperature and predominance of the NiTi alloy in phase R. The XRD results confirmed the DSC findings. Differences in the parameters measured between different types of instruments in the tests of torsional resistance, bending at 45º and flexural fatigue were always considered with a significance level of 95%. The results for the flexibility tests showed that the HTP group proved to be the most flexible, with the lowest values, followed by PDL and SEP. In the results of the torsion tests it was possible to observe that SEP presented higher values of torque followed by PDL and HTP (p <.05). Fatigue resistance tests showed higher mean NCF values for HTP, followed by PDL and SEP. However, a worse behavior of the PDL would only be evidenced clinically if the instruments were used several times greater than that recommended by the manufacturer. It can be concluded that changing the manufacturing process of endodontic instruments, inverting the machining and heat treatment steps, led, in fact, to a change in the mechanical behavior of Prodesign Logic instruments in relation to the prototypes.

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Twelve Holstein cows were given diets containing soybean supplied in different ways in order to identify possible changes in lactation performance and evaluate the economic feasibility of the diets. The diets included: soybean meal only (SM-control); raw soybean (RaS); roasted soybean (RoS) and soybean meal plus 5% urea (SMU). The forage consisted of corn silage. We analyzed the dry matter intake, milk production and collected milk samples. To estimate digestibility, we collected six samples of feces over a period of six consecutive days. The intake of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF) and non-fiber carbohydrates (NFC) did not differ among treatments. On the other hand, crude protein (CP) intake was influenced by the diets, and the highest mean values of ether extract (EE) were found with the RaS and RoS diets. The intake of total digestible nutrients (TDN) was lower in the RaS and RoS diets compared to the control diet. DM, OM, CP, EE, and NDF digestibility were not affected by the different diets, while NFCs were reduced in the RoS diet and TDN decreased with both the RaS and RoS diets. There were also no differences observed across diets for total milk production, production corrected to 3.5% fat, diet efficiency, or milk per kilogram of dry matter and/or crude protein. We conclude that raw and roasted soybeans as well as concentrate plus...(AU)

Utilizou-se 12 animais da raça Holandesa para avaliar o efeito de dietas contendo soja fornecida de diferentes formas e obter informações sobre possíveis alterações no desempenho lactacional como também verificar sua viabilidade econômica. As dietas constituíam-se de farelo de soja exclusivo (FS-controle); soja crua (SC); soja tostada (ST) e farelo de soja mais 5% de uréia (FSU). O volumoso foi à silagem de milho. Foram registrados consumo de matéria seca, produção de leite e colhidas amostras de leite. Para estimativa da digestibilidade foram coletadas seis amostras de fezes durante seis dias consecutivos. Os consumos de matéria seca (MS), matéria orgânica (MO), fibra detergente neutra (FDN) e carboidratos não fibrosos (CNF) não diferiram. O consumo de proteína bruta (PB) foi influenciado pelas dietas e as maiores médias de extrato etéreo (EE) foram com a SC e ST. O consumo dos nutrientes digestíveis totais (NDT) foi menor com a inclusão da SC e ST em relação à dieta controle. A digestibilidade da MS, MO, PB, EE, FDN não foram afetados e o CNF foi reduzido com ST e do NDT diminuiu com SC e ST. A produção total de leite e corrigida para 3,5% de gordura, sua eficiência e leite por quilograma de matéria seca e/ou proteína bruta não diferiram. Os grãos de soja crus e tostados como também concentrado adicionado de 5% de ureia na matéria seca podem ser usados como alternativas na...(AU)

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Twelve Holstein cows were given diets containing soybean supplied in different ways in order to identify possible changes in lactation performance and evaluate the economic feasibility of the diets. The diets included: soybean meal only (SM-control); raw soybean (RaS); roasted soybean (RoS) and soybean meal plus 5% urea (SMU). The forage consisted of corn silage. We analyzed the dry matter intake, milk production and collected milk samples. To estimate digestibility, we collected six samples of feces over a period of six consecutive days. The intake of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF) and non-fiber carbohydrates (NFC) did not differ among treatments. On the other hand, crude protein (CP) intake was influenced by the diets, and the highest mean values of ether extract (EE) were found with the RaS and RoS diets. The intake of total digestible nutrients (TDN) was lower in the RaS and RoS diets compared to the control diet. DM, OM, CP, EE, and NDF digestibility were not affected by the different diets, while NFCs were reduced in the RoS diet and TDN decreased with both the RaS and RoS diets. There were also no differences observed across diets for total milk production, production corrected to 3.5% fat, diet efficiency, or milk per kilogram of dry matter and/or crude protein. We conclude that raw and roasted soybeans as well as concentrate plus...

Utilizou-se 12 animais da raça Holandesa para avaliar o efeito de dietas contendo soja fornecida de diferentes formas e obter informações sobre possíveis alterações no desempenho lactacional como também verificar sua viabilidade econômica. As dietas constituíam-se de farelo de soja exclusivo (FS-controle); soja crua (SC); soja tostada (ST) e farelo de soja mais 5% de uréia (FSU). O volumoso foi à silagem de milho. Foram registrados consumo de matéria seca, produção de leite e colhidas amostras de leite. Para estimativa da digestibilidade foram coletadas seis amostras de fezes durante seis dias consecutivos. Os consumos de matéria seca (MS), matéria orgânica (MO), fibra detergente neutra (FDN) e carboidratos não fibrosos (CNF) não diferiram. O consumo de proteína bruta (PB) foi influenciado pelas dietas e as maiores médias de extrato etéreo (EE) foram com a SC e ST. O consumo dos nutrientes digestíveis totais (NDT) foi menor com a inclusão da SC e ST em relação à dieta controle. A digestibilidade da MS, MO, PB, EE, FDN não foram afetados e o CNF foi reduzido com ST e do NDT diminuiu com SC e ST. A produção total de leite e corrigida para 3,5% de gordura, sua eficiência e leite por quilograma de matéria seca e/ou proteína bruta não diferiram. Os grãos de soja crus e tostados como também concentrado adicionado de 5% de ureia na matéria seca podem ser usados como alternativas na...

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