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Este estudo investigou a eficácia biomecânica de infraestruturas de próteses feitas de cobalto-cromo (CoCr) e compósito de fibra de vidro (FVRC), implantadas em mandíbulas edêntulas. A distribuição de densidade foi investigada utilizando um modelo ósseo sintético, equipado com extensômetros, para simular condições anatômicas e biomecânicas humanas. Os implantes de conexão interna cone morse fabricados pela Conexão Sistemas de Próteses, Arujá, São Paulo, Brasil, têm diâmetro e comprimento de 4.0mm e 13mm, respectivamente, e os intermediários protéticos selecionados foram Micro Unit Sólidos da mesma marca para plataforma cone morse, com altura de transmucoso 2,5 mm, foram utilizados para suportar as infraestruturas de próteses híbridas. Por meio de extensometria, mediu-se a deformação óssea sob carga ao redor dos quatro implantes, comparando as performances das infraestruturas CoCr e FVRC. Os resultados revelaram informações importantes sobre a seleção de materiais para infraestruturas de próteses, com foco específico nas barras de FVRC e CoCr. Os testes "in vitro" e análises estatísticas destacaram que as barras de FVRC produziram menores microdeformações em comparação com as de CoCr sob carga. Essa diferença foi estatisticamente significativa, indicando que a FVRC possui uma capacidade superior de absorver e distribuir carga de maneira mais eficiente. No entanto, ressalta-se a necessidade de estudos futuros, incluindo pesquisas clínicas, para explorar totalmente as implicações desses achados e aprimorar ainda mais as práticas de reabilitação oral com implantes (AU)

This study investigated the biomechanical effectiveness of prosthetic infrastructures made of cobalt-chromium (CoCr) and fiberglass composite (FGC), implanted in edentulous jaws. The density distribution was investigated using a synthetic bone model, equipped with strain gauges, to simulate human anatomical and biomechanical conditions. The morse cone internal connection implants manufactured by Conexão Sistemas de Próteses, Arujá, São Paulo, Brazil, have a length of 4.0mm and 13mm, respectively, and the prosthetic intermediates selected were Micro Unit Solids of the same brand for a morse cone platform, with a transmucosal height of 2.5 mm, were used to support hybrid prosthetic infrastructures. Using extensometry, bone deformation under load around the four implants was measured, comparing with the performance of the CoCr and FGC infrastructures. The results revealed important information about the selection of materials for prosthetic infrastructures, with a specific focus on FGC and CoCr bars. "In vitro" tests and statistical analyzes highlighted that FGC bars produced smaller microdeformations compared to CoCr bars under load. This difference was statistically significant, demonstrating that FGC has a superior capacity to absorb and distribute load more efficiently. However, the need for future studies, including clinical research, is highlighted to fully explore the implications of these findings and further improve oral rehabilitation practices with implants. (AU)

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A major full-scale experiment (the TULIP - Tunneling and Limitations on the Impact on Piles - research project) was conducted in 2020 on Line 16 of the Grand Paris Express project (France). Its objective was to analyze the tunnel boring machine-soil-pile interactions occurring during tunnel excavation near piled structures in the context of the geology of the Paris basin. This data paper summarizes the main measurements made during this experiment, namely: (i) the horizontal and vertical displacements measured in the ground, on the surface and in the thickness of the cover, (ii) the settlements of the pile heads, and the variations of the normal forces in the pile depth. These data, interpreted in two articles cited in the references, may be of interest for the calibration of analytical and numerical models dedicated to the estimation of the impact of TBM excavation on neighboring constructions, in particular those based on piles.

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Background: Expansins play an important role in cell wall metabolism and fruit softening. Determination of expansin activity is a challenging problem since it depends on measuring cell wall properties by using ad hoc extensometers, a fact that has strongly restricted its study. Then, the objective of the work was to adapt a methodology to measure cell wall creep and expansin activity using a commercial texture meter, equipped with miniature tensile grips and an ad hoc cuvette of easy construction. Results: It was possible to measure hypocotyls acid growth and expansin activity in a reliable and reproducible way, using a commercial texture meter, common equipment found in laboratories of food science or postharvest technology. Expansin activity was detected in protein extracts from cucumber hypocotyls, tomato and strawberry fruits, and statistical differences in expansin activity were found in both fruit models at different ripening stages. Conclusions: The possibility of measuring expansin activity following this adapted protocol with a commercial texture meter could contribute to ease and increase the analysis of expansin in different systems, leading to a better understanding of the properties of these proteins under different experimental conditions.

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