In recent years, studies of composite materials have focused on the use of natural fibres as an alternative to synthetic ones. Their attractive mechanical properties, sustainability, low cost and low weight have leveraged research in this area, with the potential of a variety of applications in the engineering field. In this paper, a Full Factorial Design (2¹6¹) experiment was performed to identify the effect of silica microparticle inclusions and the stacking sequence of glass fibre cross-ply fabric and short sisal fibre layers on the apparent density, tensile and flexural strength and modulus of hybrid epoxy composites. In general, the hybrid composites with higher number of glass fibre layers achieve higher values of tensile and flexural strength (348 MPa and 663.28 MPa), tensile and flexural modulus (22 GPa and 2.50 GPa) and higher apparent density (2.02 g/cm³). It is, however, noteworthy that the incorporation of silica particles improves the mechanical performance of composites containing larger amounts of sisal fibres.

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In the last decades the biocomposites have been widely used in the construction, automobile and aerospace industries. Not only the interface transition zone (ITZ) but also the heterogeneity of natural fibres affects the mechanical behaviour of these composites. This work focuses on the numerical and experimental analyses of a polymeric co mposite fabricated with epo xy resin and unidirectional sisal and banana fibres. A three -d imensional model was set to analyze the composites using the elastic properties of the individual phases. In addition, a two-dimensional model was set taking into account the effective composite properties obtained by micro mechanical models. A tensile testing was performed to validate the numerical analyses and evaluating the interface condition of the constitu tive phases.

The work describes the analytical and experimental characterisation of a class of polymeric composites made from epoxy matrix reinforced with unidirectional natural sisal and banana fibres with silica microparticles and maleic anhydride fabricated by manual moulding. The analytical models, ROM rule of mixtures and Halpin-Tsai approach, have been used in conjunction with a Design of Experiments (DOE) analysis from tensile tests carried out on 24 different composites architectures. The following experimental factors were analyzed in this work: type of fibres (sisal and banana fibres), volume fraction of fibres (30% and 50%) and modified matrix phase by adding silica microparticles (0%wt, 20%wt and 33%wt) and maleic anhydride (0%wt and 2%wt). The ROM approach has shown a general good agreement with the experimental data for composites manufactured with 30%vol of natural fibres, which can be attributed to the strong adhesion found between the phases. On the opposite, the semi empirical model proposed by Halpin and Tsai has shown greater fidelity with composites manufactured from 50%vol of natural fibres, which exhibit a weak interfacial bonding. The addition of microsilica and maleic anhydride in the system did not enhance the adhesion between the phases as expected.

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This research aimed to employ two methods of calculation to obtain the bending modulus of elasticity in wooden specimens of Paricá (Shizolobium amazonicum), a simplified, adapted from the Brazilian standard ABNT NBR 7190, and another alternative based on the least squares method, in order to compare the efficiency of both. Therefore, some defects in wood specimens were created, based on the combination between the positions of the rips (damage) along the axis of the pieces (8.63, 17.25 and 25.86 cm) and their respective lengths (5, 10 and 15 mm), leading to a full factorial design of the type 3 2 , providing nine different combinations, apart from the reference condition (specimens without defects). The results of the confidence intervals revealed that the modulus of elasticity for both ways of calculation were equivalent for non-defective pieces, which did not occur with the inclusion of the defects in the specimens. In analysis of variance, the position, the length of the defects and the interaction between both proved to be not significant in the modulus of elasticity obtained from the methodology adapted from the Brazilian standard, which did not occur with the modulus of elasticity obtained from the least squares approach, proving to be more accurate than the simplified methodology, thus, emphasizing the importance of its use.

Temos visto no Judiciário, atualmente, um papel ativo na vida institucional brasileira. Todavia, esse ativismo judicial, ora aplaudido, ora criticado, deve ser visto com ressalvas. De fato, a atuação do Poder Judiciário, embora algumas vezes necessária, não pode invadir o campo de atuação dos demais Poderes, sob pena de comprometer a democracia e representar a judicialização da política, como já advertiu Carl Schmitt. Assim, o mérito das políticas públicas, atinente à competência do Poder Executivo, deve ficar fora do controle jurisdicional. O objeto do presente estudo será, assim, estabelecer os limites do controle judicial em relação às políticas públicas. Palavras-chave: Democracia. Constitucionalismo. Ativismo judicial. Autolimitação. Política pública. 1 Introdução A atuação do Poder Judiciário, em algumas questões, tem sido objeto de grandes polêmicas. O debate polariza-se entre aqueles que defendem a sua atuação livre e sem limites, e outros que pregam a sua autolimitação. O ativismo, entendido como "[...] uma postura a ser adotada pelo magistrado que o leve ao reconhecimento da sua atividade como elemento fundamental para o eficaz e efetivo exercício da atividade jurisdicional", 2 tem sido objeto de resistências em face da possível ofensa ao princípio da separação de poderes, consagrado no segundo artigo da Constituição da República.

O objetivo do estudo foi avaliar o rendimento e a composição centesimal de filés de saramunetes (Pseudupeneus maculatus) e da carne mecanicamente separada (CMS) sem lavar, com uma e duas lavagens com água. Os saramunetes apresentaram rendimento de filés ligeiramente inferior quando comparados com outros peixes. Por outro lado, o rendimento da CMS foi próximo ao observado em outros peixes comerciais. A umidade das CMS foi maior (P < 0,05) que a dos filés, sendo que o aumento do número de lavagens daCMS causou aumento da umidade. Os filés apresentaram alto teor proteico, superior (P < 0,05) ao da CMS, e baixa porcentagem de lipídeos. A CMS apresentou porcentagem de lipídeos superior à dos filés, e o aumento do número de lavagens da CMS causou diminuição (P < 0,05) na porcentagem de lipídeos. A porcentagem de cinzas da CMS foi superior à dos filés e houve também diminuição (P < 0,05) após a lavagem. A composiçãocentesimal da CMS sem lavar foi próxima à do filé. Portanto, recomenda-se a não lavagem da CMS de saramunetes para evitar perdas de compostos nutricionais (proteína, lipídeos e cinzas) e a formação de resíduos líquidos.