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Introduction: Post-processing (PP) is performed to improve the surface, which can favor microbial adhesion and consequent pathological manifestations that impair the indication of polylactic acid (PLA) obtained by fused filament fabrication (FFF) for biomedical applications. This aims to evaluate the influence of chemical, thermal, and mechanical PP on the adhesion of Streptococcus mutants and Candida albicans, roughness, and wettability of the PLA obtained by FFF with and without thermal aging. Methods: The specimens were designed in the 3D modeling program and printed. The chemical PP was performed by immersion in chloroform, the thermal by the annealing method, and the mechanical by polishing. Thermal aging was performed by alternating the temperature from 5 °C to 55 °C with 5000 cycles. Colony-forming unit (CFU/mL) counting was performed on dual-species biofilm of C. albicans and S. mutans. Roughness was analyzed by rugosimeter and wettability by the sessile drop technique. Data were verified for normality using the Shapiro-Wilk test, two-way ANOVA (α = 0.05) applied for CFU and wettability, and Kruskal-Wallis (α = 0.05) for roughness. Results: Chemical, thermal, and mechanical PP methods showed no influence on CFU/mL of C. albicans (p = 0.296) and S. mutans (p = 0.055). Thermal aging did not influence microbial adhesion. Chemical PP had lower roughness, which had increased after aging. Wettability of the mechanical PP was lower. Conclusions: Post-processing techniques, do not present an influence on the adhesion of S. mutans and C. albicans in PLA obtained by FFF, chemical PP reduced roughness, and mechanical reduced wettability. Thermal aging did not alter the microbial adhesion and altered the roughness and wettability.

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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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This research aims to improve data post-processing from an acoustic Doppler current profiler (ADCP) to obtain additional depth information with a high-quality bathymetric result. To validate the depth, dataset in a control area was used a scaled rod, the RTK (Real-Time Kinematic) positioning technique, and a single beam echo sounder (SBES). The developed post-processing and validation in the control area applied to a small region of a water supply reservoir in Brazil. A robust local regression method eliminated outliers from the raw data. Subsequently, a linear regression model was generated for the beams from the ADCP to adjust depths and improve the dataset. The statistical hypothesis test performed before and after the adjustment supported the validation of data processing. The resulting volumes calculated from the ADCP raw data showed a difference of 30% with SBES, which is usually the standard equipment used for bathymetric surveys. The proposed post-processing techniques declined to < 1% of the volume discrepancy. The raw dataset standard deviation was 0.15 m on average for Doppler beams, and after adjusts, this value dropped to 0.03 m. The results showed the necessity of a post-processing method to improve depth data quality from ADCP. Thus, the procedure described in this document can be used for bathymetric surveys using ADCP for analysis concerning the estimation of reservoir volume.

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ABSTRACT This study presents a classifier prediction in groups for the Brazilian Football Championship of both A and B leagues, from the results of the first half of each championship. With assertive predictions of the group where a team will end the championship, strategic planning can be performed in the squad, such as new hiring, specific training for athletes, and possible championships that the team will be entitled to participate in according to the group classification. In order to find the predictions, two techniques of artificial intelligence were applied: Multi-Layer Perceptron (MLP), which is a type of artificial neural network, and Support Vector Machine (SVM). Preliminary results show that the proposed methodology is very promising, with more than 40% successful cases with MLP and almost 50% with SVM. Moreover, results indicate that the methodology is able to make a reasonable prediction by missing one group of the true group at the end of the championship. The SVM technique was slightly better than MLP. A post-processing analysis of the SVM results was applied to the 2018 A league data from the Brazilian championship, resulting in 85% success indicator of groups.

RESUMO Este trabalho apresenta uma previsão de classificação em grupos para as equipes do campeonato brasileiro de futebol tanto da série A quanto da série B a partir dos resultados do primeiro turno de cada campeonato. Com previsões assertivas do grupo onde um time irá finalizar o campeonato, pode-se realizar um planejamento estratégico no elenco tal como novas contratações, treinos específicos dos atletas e possíveis campeonatos que o time terá direito de participar de acordo com o grupo em que se classificar. Para encontrar as previsões, aplicou-se as técnicas rede neural artificial Multi Layer Perceptron (MLP) e Support Vector Machine (SVM). Resultados preliminares indicam que a metodologia proposta é bastante promissora, acertando em mais de 40% dos casos com a MLP e quase 50% com o SVM. Além disso, os resultados indicam que a metodologia também é capaz de realizar uma boa previsão errando em um grupo do verdadeiro grupo ao final do campeonato. A técnica SVM se mostrou um pouco superior à MLP. Um pós processamento nos resultados do SVM é aplicado aos dados do ano de 2018 da série A do campeonato brasileiro, resultando em 85% de acertos dos grupos.

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The range of selective laser sintering (SLS) materials is currently limited, and the available materials are often of high cost. Moreover, the mechanical strength of wood-plastic SLS parts is low, which restricts the application of a SLS technology. A new composite material has been proposed to address these issues, while simultaneously valorizing agricultural and forestry waste. This composite presents several advantages, including reduced pollution associated with waste disposal and reduced CO2 emission with the SLS process in addition to good mechanical strength. In this article, a novel and low-cost Prosopis chilensis/polyethersulfone composite (PCPC) was used as a primary material for SLS. The formability of PCPC with various raw material ratios was investigated via single-layer experiments, while the mechanical properties and dimensional accuracy of the parts produced using the various PCPC ratios were evaluated. Further, the microstructure and particle distribution in the PCPC pieces were examined using scanning electron microscopy. The result showed that the SLS part produced via 10/90 (wt/wt) PCPC exhibited the best mechanical strength and forming quality compared to other ratios and pure polyethersulfone (PES), where bending and tensile strengths of 10.78 and 4.94 MPa were measured. To improve the mechanical strength, post-processing infiltration was used and the PCPC-waxed parts were enhanced to 12.38 MPa and 5.73 MPa for bending and tensile strength.

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A transição do sistema radiográfico convencional para os sistemas radiográficos digitais, ao longo de vinte anos, tem transformado as salas de laudos nos serviços de diagnóstico por imagem, tanto na medicina humana quanto na medicina veterinária. Atualmente, com a introdução do sistema radiográfico computadorizado e do digital direto na rotina de alguns hospitais e laboratórios de imagem, o uso das ferramentas de pós-processamento tem se tornado cada vez mais frequente e importante. Diante da necessidade de estudos acerca desses recursos, a presente revisão de literatura tem como objetivo contribuir para a compreensão da física envolvida no processo de aquisição das imagens radiográficas computadorizadas e apresentar ao leitor, de forma simples, a evolução das pesquisas realizadas para validar o uso da imagem digital na avaliação do tórax e as contribuições do pós-processamento nas aplicações clínicas para o estabelecimento do diagnóstico.

The transition from conventional to digital radiographic systems has transformed the diagnostic imaging services in both human and veterinary medicine in the last 20 years. The introduction of direct and indirect digital radiographic systems in the routine of many hospitals and image laboratories has turned the use of post-processing tools more frequent and important. Thus, the need of knowledge about these resources motivated this literature review, which aims to contribute in a simple way to the understanding of the physics involved in the acquisition of computerized radiographic images. Additionally, we hereby present the research evolution to validate the use of digital images for thoracic evaluation and the contribution of post-processing to clinical applications and diagnosis.

La transición del sistema radiográfico convencional para los sistemas radiográficos digitales, a lo largo de veinte años, ha transformado la sala de diagnóstico de los servicios de radiología, tanto en medicina humana como en medicina veterinaria. Actualmente, con la introducción del sistema radiográfico computarizado y del digital directo en algunos hospitales y laboratorios de imagen, el uso de herramientas de postprocesamiento se ha hecho cada día más frecuente e importante. Frente a la necesidad de estudios sobre estos recursos, esta revisión de la literatura tiene como objetivo contribuir para el entendimiento de los conceptos físicos relacionados con la adquisición de radiografías computarizadas, y presentar al lector, de una forma simple, la evolución de las investigaciones realizadas para validar el uso de la imagen digital en los exámenes de la cavidad torácica, y las contribuciones del postprocesamiento en las aplicaciones clínicas para establecer un diagnóstico.

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A transição do sistema radiográfico convencional para os sistemas radiográficos digitais, ao longo de vinte anos, tem transformado as salas de laudos nos serviços de diagnóstico por imagem, tanto na medicina humana quanto na medicina veterinária. Atualmente, com a introdução do sistema radiográfico computadorizado e do digital direto na rotina de alguns hospitais e laboratórios de imagem, o uso das ferramentas de pós-processamento tem se tornado cada vez mais frequente e importante. Diante da necessidade de estudos acerca desses recursos, a presente revisão de literatura tem como objetivo contribuir para a compreensão da física envolvida no processo de aquisição das imagens radiográficas computadorizadas e apresentar ao leitor, de forma simples, a evolução das pesquisas realizadas para validar o uso da imagem digital na avaliação do tórax e as contribuições do pós-processamento nas aplicações clínicas para o estabelecimento do diagnóstico.(AU)

The transition from conventional to digital radiographic systems has transformed the diagnostic imaging services in both human and veterinary medicine in the last 20 years. The introduction of direct and indirect digital radiographic systems in the routine of many hospitals and image laboratories has turned the use of post-processing tools more frequent and important. Thus, the need of knowledge about these resources motivated this literature review, which aims to contribute in a simple way to the understanding of the physics involved in the acquisition of computerized radiographic images. Additionally, we hereby present the research evolution to validate the use of digital images for thoracic evaluation and the contribution of post-processing to clinical applications and diagnosis.(AU)

La transición del sistema radiográfico convencional para los sistemas radiográficos digitales, a lo largo de veinte años, ha transformado la sala de diagnóstico de los servicios de radiología, tanto en medicina humana como en medicina veterinaria. Actualmente, con la introducción del sistema radiográfico computarizado y del digital directo en algunos hospitales y laboratorios de imagen, el uso de herramientas de postprocesamiento se ha hecho cada día más frecuente e importante. Frente a la necesidad de estudios sobre estos recursos, esta revisión de la literatura tiene como objetivo contribuir para el entendimiento de los conceptos físicos relacionados con la adquisición de radiografías computarizadas, y presentar al lector, de una forma simple, la evolución de las investigaciones realizadas para validar el uso de la imagen digital en los exámenes de la cavidad torácica, y las contribuciones del postprocesamiento en las aplicaciones clínicas para establecer un diagnóstico.(AU)

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