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Failure by fatigue can be sudden and catastrophic. Therefore, ensuring that dental implants, which are under constant cyclic loading, do not fail to fatigue is imperative. The majority of the studies about the topic only performed in vitro tests, which are expensive and time-consuming. The Finite Element (FE) method is less costly and it allows the simulation of several different loading scenarios. Nonetheless, there are only a few studies analysing fatigue in dental prostheses using FE models, and the few available did not include all the relevant parameters, such as geometry effect, surface finishing, etc. Therefore, this study aimed to analyse the fatigue behaviour of a single-unit dental implant with two screws using a combination of the numerical results and the traditional fatigue criteria - a combination that was not yet fully and correctly explored. A finite element model comprising a single implant, one abutment, one abutment screw, one fixation screw and one prosthetic crown was developed. Material properties were assigned based on literature data. A 100 N load was applied to mimic the mastication forces and fatigue analysis was conducted using the Gerber, Goodman and Soderberg fatigue criteria. The fatigue analysis demonstrated that the abutment screw could fail in less than 1 year, depending on the criteria, while the fixation screw exhibits an infinite life. The results illustrated the importance of analysing the fatigue behaviour of dental implants and highlighted the potential of finite element models to simulate the biomechanical behaviour of dental implants.

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This study presents a methodology that combines experimental tests and the finite element method, which is able to analyse the influence of the geometry on the mechanical behaviour of stents made of bioabsorbable polymer PLA (PolyLactic Acid) during their expansion in the treatment of coarctation of the aorta (CoA). Tensile tests with standardized specimen samples were conducted to determine the properties of a 3D-printed PLA. A finite element model of a new stent prototype was generated from CAD files. A rigid cylinder simulating the expansion balloon was also created to simulate the stent opening performance. A tensile test with 3D-printed customized stent specimens was performed to validate the FE stent model. Stent performance was evaluated in terms of elastic return, recoil, and stress levels. The 3D-printed PLA presented an elastic modulus of 1.5 GPa and a yield strength of 30.6 MPa, lower than non-3D-printed PLA. It can also be inferred that crimping had little effect on stent circular recoil performance, as the difference between the two scenarios was on average 1.81%. For an expansion of diameters ranging from 12 mm to 15 mm, as the maximum opening diameter increases, the recoil levels decrease, ranging from 10 to 16.75% within the reported range. These results point out the importance of testing the 3D-printed PLA under the conditions of using it to access its material properties; the results also indicate that the crimping process could be disregarded in simulations to obtain fast results with lower computational cost and that new proposed stent geometry made of PLA might be suitable for use in CoA treatments-the approach that has not been applied before. The next steps will be to simulate the opening of an aorta vessel using this geometry.

RESUMO

This study presents a methodology that combines experimental tests and the finite element method, which is able to analyse the influence of the geometry on the mechanical behaviour of stents made of bioabsorbable polymer PLA (PolyLactic Acid) during their expansion in the treatment of coarctation of the aorta (CoA). Tensile tests with standardized specimen samples were conducted to determine the properties of a 3D-printed PLA. A finite element model of a new stent prototype was generated from CAD files. A rigid cylinder simulating the expansion balloon was also created to simulate the stent opening performance. A tensile test with 3D-printed customized stent specimens was performed to validate the FE stent model. Stent performance was evaluated in terms of elastic return, recoil, and stress levels. The 3D-printed PLA presented an elastic modulus of 1.5 GPa and a yield strength of 30.6 MPa, lower than non-3D-printed PLA. It can also be inferred that crimping had little effect on stent circular recoil performance, as the difference between the two scenarios was on average 1.81%. For an expansion of diameters ranging from 12 mm to 15 mm, as the maximum opening diameter increases, the recoil levels decrease, ranging from 10 to 16.75% within the reported range. These results point out the importance of testing the 3D-printed PLA under the conditions of using it to access its material properties; the results also indicate that the crimping process could be disregarded in simulations to obtain fast results with lower computational cost and that new proposed stent geometry made of PLA might be suitable for use in CoA treatments-the approach that has not been applied before. The next steps will be to simulate the opening of an aorta vessel using this geometry.

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INTRODUCTION: The knee extension prone test (KEPT) can be a low-cost and affordable alternative for this assess knee hyperextension deficit. OBJECTIVE: To analyze concurrent validity and reliability of a new method for assessing knee extension prone (knee extension prone test; KEPT). METHODS: Participants were divided into two groups: Group 1 comprised healthy participants (HG) and Group 2 comprised participants with a history of knee injury (IG). Two examiners performed the following evaluations: (1) lateral knee goniometry, (2) anterior tibial inclinometry, (3) lateral photogrammetry in supine, (4) lateral photogrammetry in prone, and (5) KEPT. Concurrent validity was analyzed by Pearson's linear correlation coefficient (r), and intra- and inter-examiner reliability were analyzed by intraclass correlation coefficient (ICC). RESULTS: KEPT demonstrated good intra-examiner (ICC = 0.85, 95% CI = 0.75-0.89) and excellent inter-examiner (ICC = 0.92, 95% CI = 0.88-0.94) reliability. The standard error of measurement was 0.47° and 1.30° and the minimum detectable change was 2.35° and 6.5° for intra- and inter-examiner agreement, respectively. Concurrent validity of KEPT ranged from moderate to good (r = 0.54-0.78, p < 0.01). CONCLUSION: KEPT is a valid and reliable method for assessing knee hyperextension deficit in both healthy individuals and patients with knee injuries.

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Resumo Este trabalho apresenta uma reflexão acerca da emergência de novas discursividades no campo político com o movimento de ocupações de escolas no Brasil, entre 2015 e 2016, considerando a dimensão utópica presente nessas experiências estudantis que se conjugaram a partir da posição de um não-saber. Articula-se com registros bibliográficos, fotográficos e audiovisuais, convocando o pensamento para uma conversa entre política e utopia.

Abstract This paper reflects on the emergence of new political discourses regarding students' lived experience of school occupations in Brazil, between 2015 and 2016, considering their utopic content built upon a not-knowing position. The text articulates bibliographic research, photographic and audio-visual records, inviting a debate about politics and utopia.

Résumé Cet article réfléchit à l'émergence de nouveaux discours politiques concernant les occupation juvéniles dans les écoles au Brésil, entre 2015 et 2016, en considérant leur contenu utopique construit sur une position de non-savoir. Le texte articule des recherches bibliographiques, des enregistrements photographiques et audiovisuels, invitant à un débat sur la politique et l'utopie.

Resumen Este trabajo presenta una reflexión sobre las urgencias de las nuevas discursividades en el campo político a partir del movimiento de ocupaciones de escuelas en Brasil, entre 2015 y 2016, considerando la dimensión utópica presente en estas experiencias de los estudiantes que están intercaladas a partir de la posición de un no-saber. Para ello, se utilizan bibliografía, registros fotográficos y audiovisuales, que estimulan la discusión entre política y utopía.

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Dental implants are widely used as a long-term treatment solution for missing teeth. A titanium implant is inserted into the jawbone, acting as a replacement for the lost tooth root and can then support a denture, crown or bridge. This allows discreet and high-quality aesthetic and functional improvement, boosting patient confidence. The use of implants also restores normal functions such as speech and mastication. Once an implant is placed, the surrounding bone will fuse to the titanium in a process known as osseointegration. The success of osseointegration is dependent on stress distribution within the surrounding bone and thus implant geometry plays an important role in it. Optimisation analyses are used to identify the geometry which results in the most favourable stress distribution, but the traditional methodology is inefficient, requiring analysis of numerous models and parameter combinations to identify the optimal solution. A proposed improvement to the traditional methodology includes the use of Design of Experiments (DOE) together with Response Surface Methodology (RSM). This would allow for a well-reasoned combination of parameters to be proposed. This study aims to use DOE, RSM and finite element models to develop a simplified optimisation analysis method for dental implant design. Drawing on data and results from previous studies, two-dimensional finite element models of a single Branemark implant, a multi-unit abutment, two prosthetic screws, a prosthetic crown and a region of mandibular bone were built. A small number of combinations of implant diameter and length were set based on the DOE method to analyse the influence of geometry on stress distribution at the bone-implant interface. The results agreed with previous studies and indicated that implant length is the critical parameter in reducing stress on cortical bone. The proposed method represents a more efficient analysis of multiple geometrical combinations with reduced time and computational cost, using fewer than a third of the models required by the traditional methods. Further work should include the application of this methodology to optimisation analyses using three-dimensional finite element models.

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Neste ensaio procuramos construir alguns laços entre o infantil na concepção psicanalítica e o universo das utopias. A partir da versão cinematográfica de Alice no país das maravilhas de Jam Švankmajer - em que o autor consegue nos oferecer uma perspectiva do universo carroliano de Alice, aproximado do sonho e do brincar das crianças na concepção freudiana - procuramos aproximar o infantil e a utopia, relacionando o "País das maravilhas" apresentado por Švankmajer, da ilha Utopia, de Morus, no sentido de demonstrar como o infantil permite o acesso às construções utópicas a partir de um corte ou furo nas palavras-imagens do infantil, como exigência de criação, pelo brincar, de um litoral que nos dá acesso a ilhas, territórios que resistem à literalidade das formas instituídas da realidade, como utopia.

In this essay, we have aimed at building a few connections between the psychoanalytical conception of the infantile and the utopian universe. Based on Jam Švankmajer's cinematographic version of Alice in Wonderland - which offers a perspective of Lewis Carroll's universe of Alice that comes close to Freud's concept of dreams and child's play - we tried to find connections between the infantile and utopia by relating Švankmajer's "Wonderland" to Morus' island of Utopia to show how the infantile allows to access utopian constructions by a cut or hole in the word-images of the infantile, as a demand to create, through play, a coastline that gives us access to islands, territories that resist the literality of the instituted shapes of reality, such as utopia does.

Dans cet essai, nous cherchons à tisser quelques liens entre l'infantile de la notion psychanalytique et l'univers des utopies. Sur la base de la version cinématographique d'Alice au pays des Merveilles de Jam Švankmajer - dans laquelle l'auteur nous offre une perspective de l'univers carrollien d'Alice semblable au rêve et au jeu d'enfants du point de vue freudien -, nous essayons d'approcher l'infantile et l'utopie en établissant un rapport entre «Le Pays de Merveilles¼, présenté par Švankmajer et l'île «Utopia¼ de Morus. Ainsi, nous visons à montrer comment l'infantile donne accès à des constructions utopiques grâce à une coupure ou à la percée d'un trou dans les mots-images de l'infantile, menée comme une exigence de la création, par le jeu, d'une côte qui offre accès à des îles, des territoires qui résistent à la littéralité des formes établies par la réalité, c'est-à-dire l'utopie.

En este ensayo, buscamos construir algunos lazos entre lo infantil, en la concepción psicoanalítica, y el universo de las utopías. A partir de la versión cinematográfica de Alicia en el país de las maravillas, de Jam Švankmajer; en donde el autor logra ofrecernos una perspectiva del universo carroliano de Alice, alrededor del sueño y del jugar de los niños en la concepción freudiana, buscamos aproximar lo infantil y la utopía, relacionando el "País de las maravillas", presentado por Jam Švankmajer, con la isla de Utopía, de Moro, con la intención de demostrar cómo lo infantil abre el acceso a las construcciones utópicas a partir de un corte o agujero en las palabras/imágenes de lo infantil, como exigencia de la creación, por el jugar, de un litoral que nos da acceso a islas, territorios que se resisten a la literalidad de las formas instituidas de la realidad, como utopía.

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O presente artigo pretende trabalhar a articulação entre história e resistência na obra de Georges Perec, para pensar a potência utópica de seus textos. O autor submete a si e ao leitor às contraintes, que vão construindo um caminho individual numa jornada percorrida conjuntamente, escritor e leitor. Caminho que nos aproxima da leitura psicanalítica sobre o tempo e a história para pensarmos construções de narrativas. Perec transita no limite entre o Real da letra e o Simbólico do nome. Letra que faz operar um não-lugar, possibilidade de narrar, ou seja, através de a escrita da ficção poder se contar, o que implica acessar uma memória que também é coletiva, problematizando, assim, a relação com a história.(AU)

This article intends to work the relationship between history and resistance in the work of Georges Perec to think about the utopian power of his texts. The author submits himself and the reader to contraintes, constructing an individual pathway in a journey journeyed together of writer and reader. This is a road that brings us closer to the psychoanalytical reading about time and history to think of the narratives construction. Perec moves in the boundaries between the Real of the letter and the Symbolic of the name. A letter that makes a non-place work, the possibility of narrating, i.e. through the writing of fiction to be able to tell, which implies accessing a memory that is also collective, thus questioning the relationship with history.(AU)

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O objetivo foi avaliar a aceitabilidade, perante o mercado consumidor de duas amostras de linguiça suína, uma previamente assada e a outra somente defumada. O processo de defumação foi realizado em uma temperatura média 70°C por 11 horas. Foram aplicados 64 questionários em diferentes locais (Faculdade Estácio Atual da Amazônia, Campus Paricarana da UFRR e Campus Cauamé da UFRR). Quando questionados sobre a frequência do consumo de linguiça suína a maioria dos entrevistados 24 (37,5%) relataram que raramente a consomem e 17 (26,6%) afirmaram que consome uma vez a cada 15 dias. Foi observado que a maioria 31 (48,4%) dos entrevistados escolheram a amostra 2 (linguiça suína defumada) e 29 (45,3%) pessoas pela a amostra 1 (linguiça assada). Conclui-se que a linguiça suína defumada teve preferência maior que a não defumada.(AU)

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O objetivo foi avaliar a aceitabilidade, perante o mercado consumidor de duas amostras de linguiça suína, uma previamente assada e a outra somente defumada. O processo de defumação foi realizado em uma temperatura média 70°C por 11 horas. Foram aplicados 64 questionários em diferentes locais (Faculdade Estácio Atual da Amazônia, Campus Paricarana da UFRR e Campus Cauamé da UFRR). Quando questionados sobre a frequência do consumo de linguiça suína a maioria dos entrevistados 24 (37,5%) relataram que raramente a consomem e 17 (26,6%) afirmaram que consome uma vez a cada 15 dias. Foi observado que a maioria 31 (48,4%) dos entrevistados escolheram a amostra 2 (linguiça suína defumada) e 29 (45,3%) pessoas pela a amostra 1 (linguiça assada). Conclui-se que a linguiça suína defumada teve preferência maior que a não defumada.

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