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A large range of biodegradable polymers has been used to produce implantable medical devices. Apart from biological compatibility, these devices shall be also functional compatible and perform adequate mechanical temporary support during the healing process. However, the mechanical behavior of biodegradable materials during its degradation, which is an important aspect of the design of these biodegradable devices, is still an unexplored subject. Based on the literature, the mechanical behavior of biodegradable polymers is strain rate dependent and exhibits hysteresis upon cyclic loading. On the other hand, ductility, toughness and strength of the material decay during hydrolytic degradation. In this work, it is considered a three-dimensional time-dependent model adapted from the one developed by Bergström and Boyce to simulate the performance of biodegradable structures undergoing large deformations incorporating the hydrolysis degradation. Since this model assumes that the mechanical behavior is divided into a time independent network and a non-linear time-dependent network, it enables to simulate the monotonic tests of a biodegradable structure loaded under different strain rates. The hysteresis effects during unloading–reloading cycles at different strain levels can be predicted by the model. A parametric study of the material model parameters evolution during the hydrolytic degradation was conducted to identify which parameters are more sensible to this degradation process. The investigated model could predict very well the experimental results of a blend of polylactic acid and polycaprolactone (PLA–PCL) in the full range of strains until rupture during hydrolytic degradation. From these results and analyses, a method is proposed to simulate the three-dimensional mechanical behavior during hydrolytic degradation.

Several biodegradable polymers are used in many products with short life cycles. The performance of a product is mostly conditioned by the materials selection and dimensioning. Strength, maximum strain and toughness will decrease along its degradation, and it should be enough for the predicted use. Biodegradable plastics can present short-term performances similar to conventional plastics. However, the mechanical behavior of biodegradable materials, along the degradation time, is still an unexplored subject. The maximum strength failure criteria, as a function of degradation time, have traditionally been modeled according to first order kinetics. In this work, hyperelastic constitutive models are discussed. An example of these is shown for a blend composed of poly(L-lactide) acid (PLLA) and polycaprolactone (PCL). A numerical approach using ABAQUS is presented, which can be extended to other 3D geometries. Thus, the material properties of the model proposed are automatically updated in correspondence to the degradation time, by means of a user material subroutine. The parameterization was achieved by fitting the theoretical curves with the experimental data of tensile tests made on a PLLA-PCL blend (90:10) for different degradation times. The results obtained by numerical simulations are compared to experimental data, showing a good correlation between both results.

Apresenta os resultados do I Seminário Internacional "A Arte da Bibliografia: ferramentas históricas, problemas metodológicos e práticas contemporâneas”. A partir do relato das atividades realizadas e das problematizações feitas ao longo do evento, demonstra o papel da Bibliografia enquanto disciplina e seus desdobramentos do ponto de vista histórico, metodológico e prático. A experiência concretizou um espaço de trocas entre pesquisadores e participantes, além de colocar em evidência a importância dos estudos bibliográficos para os fundamentos da Bibliologia, Biblioteconomia, Documentação e Ciência da Informação. O evento foi uma realização do grupo de pesquisa “Ecce Liber: filosofia, linguagem e organização dos saberes”, a partir do IBICT, em parceria com CBG-UFRJ, PPGCINF-UnB, PPGB-Unirio, FFCLRP-USP e BU/SB-UFMG.

This report describes the development of a force platform based on instrumented load cells with built-in conditioning circuit and strain gages to measure and acquire the components of the force that is applied to the bike crank arm during pedaling in real conditions, and save them on a SD Card. To accomplish that, a complete new crank arm 3D solid model was developed in the SolidWorks, with dimensions equivalent to a commercial crank set and compatible with a conventional road bike, but with a compartment to support all the electronics necessary to measure 3 components of the force applied to the pedal during pedaling. After that, a 6082 T6 Aluminum Crankset based on the solid model was made and instrumented with three Wheatstone bridges each. The signals were conditioned on a printed circuit board, made on SMD technology, and acquired using a microcontroller with a DAC. Static deformation analysis showed a linearity error below 0.6% for all six channels. Dynamic analysis showed a natural frequency above 136Hz. A one-factor experiment design was performed with 5 amateur cyclists. ANOVA showed that the cyclist weight causes significant variation on the force applied to the bicycle pedal and its bilateral symmetry.

A Imprensa teve como um dos seus mais significativos impactos a vasta, intensa e acelerada produção de bibliografias, como meios de registro, organização, seleção, disponibilização e mediação de documentos. Entre as inúmeras conseqüências da Imprensa está a necessidade de se operar a chamada explosão informacional - fenômeno investigado, do ponto de vista histórico-cultural, por autores como Peter Burke e Ann Blair. A partir desta paisagem, o artigo busca estabelecer relações entre o contexto histórico-informacional da Europa Moderna e Bibliotheca Universalis, de Conrad Gesner (Séc. XVI). Bibliotheca arrola aspectos da cultura manuscrita e impressa e traz implicitamente uma profunda reflexão descritiva e semântica sobre os documentos e os saberes, conforme se evidencia nos estudos de Alfredo Serrai e Fiammetta Sabba. O “gesto bibliográfico” gesneriano é mais do que uma resposta a confusa et noxia illa librorum multitude (“confusa e irritante multidão de livros”, que hoje nos remete ao sentido da denominada information overload): é a força que arquiteta a própria Bibliografia enquanto disciplina. Printing Press had, as one of their most significant impacts, the vast, intense and accelerated production of bibliographies, as means of recording, organizing, selecting, availability and mediation of documents. One of the many consequences of Printing Press is the need to operate the so-called information explosion - a phenomenon investigated from an historical and cultural point of view by authors such as Peter Burke and Ann Blair. Based on this frame, this article seeks to establish relations between the historical and informational context of Modern Europe and the Bibliotheca Universalis, written by Conrad Gesner (16th century). The Bibliotheca enrolls aspects of manuscript and printed culture and implicitly brings a deep descriptive and semantic reflection on documents and knowledge, as evidenced in studies of Alfredo Serrai and Fiammetta Sabba. The "bibliographic gesture" of Gesner is more than just a response to the confusa et noxia illa librorum multitudo ("confusing and annoying crowd of books"), which in our days brings us to the meaning of the so-called information overload: it is the force that builds the very architecture of Bibliography as a discipline

A large range of biodegradable polymers are used in many products with short life cycle. Important applications of these are found in the biomedical field, where biodegradable materials are used to produce scaffolds that temporarily replace the biomechanical functions of a biologic tissue, while it progressively regenerates its capacities. However, the mechanical behavior of biodegradable materials along its degradation time, which is an important aspect of the project, is still an unexplored subject. In this work, hyper elastic constitutive models, such as the Neo-Hookean, the Mooney-Rivlin modified and the second reduced order are discussed. These can be used to predict the mechanical behavior of a blend composed of polylatic acid (PLA) and polycaprolactone (PCL). A numerical approach using ABAQUS® is presented, where the material properties of the model proposal are automatically updated in correspondence to the degradation time, by means of a User Material subroutine (UMAT). The parameterization of the material model proposal for different degradation times were achieved by fitting the theoretical curves with the experimental data of tensile tests. The material model proposal implemented in a subroutine could be used as a design toll for generic biodegradable devices.

P-cadherin is a cell-cell adhesion molecule, whose expression is highly associated with undifferentiated cells in normal adult epithelial tissues, as well as with poorly differentiated carcinomas. Its expression has been already reported in human embryonic stem cells and it is presumed to be a marker of stem or progenitor cells of some epithelial tissues. In normal breast, P-cadherin has an essential role during ductal mammary branching, being expressed by the monolayer of epithelial cap cells at the end buds. In mature mammary tissue, its expression is restricted to the myoepithelium; it has been postulated that it may also be present in early luminal progenitor cells. In breast cancer, P-cadherin is frequently overexpressed in high-grade tumours, being a well-established indicator of poor patient prognosis. It has been reported as an important inducer of cancer cell migration and invasion, with underlying molecular mechanisms involving the signalling mediated by its juxtamembrane domain, the secretion of matrix metalloproteases to the extracellular media, and the cleavage of a P-cadherin soluble form with pro-invasive activity. Intracellularly, this protein interferes with the endogenous cadherin/catenin complex, inducing p120-catenin delocalization to the cytoplasm, and the consequent activation of Rac1/Cdc42 and associated alterations in the actin cytoskeleton. Considering P-cadherin's role in cancer cell invasion and metastasis formation, a humanized monoclonal antibody was recently produced to antagonize P-cadherin-associated signalling pathways, which is currently under Phase I clinical trials. In this review, the most important findings about the role of P-cadherin in normal breast development and cancer will be illustrated and discussed, with emphasis on the most recent data.

Aliphatic polyesters, such as polylactic acid (PLA), polyglycolic acid (PGA), polycaprolactone (PCL), polydioxone (PDO) and others, have been commonly used in biodegradable products. Hydrolytic and/or enzymatic chain cleavage of these materials leads to α-hydroxyacids, which, in most cases, are ultimately assimilated in human body or in a composting environment. However, each of these has some shortcomings, in terms of mechanical properties and degradation time, which restrict its applications. The combination of these materials, by copolymerization or blending, enables a range of mechanical properties and degradation rates. These are extremely promising approaches which can improve or tune the original properties of the polymers. A composite solution of several materials with different degradation rates also enables tuning the rate of degradation of a device and the mechanical properties. After immersion of an aliphatic polyester device, diffusion occurs very rapidly compared to hydrolysis. Therefore, it is usually considered that hydrolysis of ester bonds starts homogeneously and has traditionally been modelled according to a first order kinetics. In this experimental study, fibres of PLA-PCL, PGA-PCL, PDO and PGA, with two different dimensions, were characterized in terms of their degradation rate under three different environments (water, NaCl and PBS) at constant temperature (37°C). Weights and mechanical properties were measured after six different degradation stages. Stages durations were different depending on materials, according to the predicted degradation times. As other thermoplastics, they are viscoelastic materials. In this experimental study mechanical properties of fibres were compared at different strain rates.

This bibliographic review is focused on ligament tissue rehabilitation, its anatomy-physiology, and, mainly, on the dimensioning considerations of a composite material solution. The suture strength is problematic during the tissue recovering, implying reduction of mobility for several months. However, early postoperative active mobilization may enable a faster and more effective recovering of tissue biomechanical functions. As the risk of tendon rupture becomes a significant concern, a repair technique must be used to withstand the tensile forces generated by active mobilization. However, to avoid stress shielding effect on ligament tissue, an augmentation device must be designed on stiffness basis, that preferably will decrease. Absorbable biocomposite reinforcements have been used to allow early postoperative active mobilization and avoid the shortcomings of current repair solutions. Tensile strength decrease of the repair, during the initial inflammatory phase, is expected, derived from oedema and tendon degradation. In the fibroblastic phase, stiffness and strength will increase, which will stabilize during the remodeling phase. The reinforcement should be able to carry the dynamic load due to locomotion with a mechanical behavior similar to the undamaged natural tissue, during all rehabilitation process. Moreover, the degradation rate must also be compatible with the ligament tissue recovering. The selection and combination of different biodegradable materials, in order to make the biocomposite reinforcement functionally compatible to the damaged sutured tissue, in terms of mechanical properties and degradation rate, is a major step on the design process. Modelling techniques allow pre-clinical evaluation of the reinforcement functional compatibility, and the optimization by comparison of different composite solutions in terms of biomechanical behavior.

Ubiquitous computing is strongly centered on the human, aiming to provide the right information through personalized interfaces and services in context of use to the applications users. We envision a ubiquitous computing based world in which a generic personalization model is applied to different applications, even if from different domains. The model is the core of a cloud-based platform, which guides developers by providing services to help them in the implementation of personalized solutions. Moreover, end-users will be less bothered when starting to use a new application, which already might know something about them in order to automatically adapt itself to the users' preferences and needs. A user's interactions with an application A might be useful to know how to personalize her experience when interacting with an application B. This paper presents the X-Users based solution in order to reach that vision, giving special attention to the personalization modeling. Important contributions of the paper are also two case studies that illustrate how X-Users can be used to help personalizing systems.

Resenha de: CRIPPA, Giulia. Poeticas da informacao: representacoes artisticas e literarias de livros, bibliotecas e de seus protagonistas. Sao Paulo: Todas as Musas, 2014. 221 p. ISBN 978-85-64137-38-7.

In cassava, apomixis could fix hetereozygosity and prevent the transmission of systemic pathogens which complicate vegetative propagation of the crop. Evidence from maternal inheritance of RAPD markers and the structure of the embryonic sac in large progeny sets of two distinct genotypes have further confirmed that apomixis occurs in cassava. Here, we have built on an earlier report of apomixis in cassava in four ways (1) we estimated the rate of faculative apomixis in the range of 2% (2) we detected the occurrence of apomixis in a second genotype, derived form a different interspecific cross; (3) apomictic behavior was demonstrated in an F1 individual and (4) embryonic evidence showed that the mode of apomixis is aposporic. Since apomixis was detected in an F1 interspecific hybrid it is possible that genes for apomixis could be transferred directly to cultivated cassava from a wild relative. Key words: Cassava, interspecific hybrid

In cassava, apomixis fixes heterosis and avoids transmission of systemic pathogens which complicate vegetative propagation of the crop. A combination of evidence from maternal inheritance of RAPD markers and the structure of the embryonic sac in large progeny sets of two distinct genotypes have further confirmed the occurrence of apomixis in cassava. We could advance further on earlier reports of the detection of apomixis in four ways: (1) we could arrive at an estimate of the rate of facultative apomixis in the range of 2%; (2) we detected the occurrence of apomixis in a second genotype, derived from a different interspecific cross; (3) apomictic behavior was demonstrated in an F1 individual and (4) parallel embryonic evidence was generated that corroborate the potential occurrence of apomixis by apospory. The fact that apomixis was detected in an F1 interspecific hybrid hints to the possibility of directly transferring genes for apomixis from a wild relative to cultivated cassava.

One of the recurrent major environmental problems is the high energy consumption. It has been challenging to find methods of persuading people to have better habits on energy usage. We are proposing the use of personalization to enhance a mobile and pervasive-based gaming approach to better foster domestic energy awareness close to people. The game is based on real-time domestic energy consumption data and presents persuasive feedback information, beyond the competitive feeling of the game. The personalization mechanisms are provided by an external web service that is designed to serve different applications, even if from different systems or domains.

The concept behind a biodegradable ligament device is to temporarily replace the biomechanical functions of the ruptured ligament, while it progressively regenerates its capacities. However, there is a lack of methods to predict the mechanical behaviour evolution of the biodegradable devices during degradation, which is an important aspect of the project. In this work, a hyper elastic constitutive model will be used to predict the mechanical behaviour of a biodegradable rope made of aliphatic polyesters. A numerical approach using ABAQUS is presented, where the material parameters of the model proposal are automatically updated in correspondence to the degradation time, by means of a script in PYTHON. In this method we also use a User Material subroutine (UMAT) to apply a failure criterion base on the strength that decreases according to a first order differential equation. The parameterization of the material model proposal for different degradation times were achieved by fitting the theoretical curves with the experimental data of tensile tests on fibres. To model all the rope behaviour we had considered one step of homogenisation considering the fibres architectures in an elementary volume.

Throughout the twentieth century audio technology has contributed greatly to the development of ethnomusicology. Initially with the creation of the phonograph and techniques of sound recording, enabling the development of phonographic archives and later with creation of technologies that provide better sound quality, lower cost and more appropriate concepts to new paradigms of the discipline, even knowing that until the middle of the twentieth century ethnomusicology not had this name, scientific approach or methodological orientation. Despite the important contribution of audio technology for ethnomusicology, seem that phonographic processes can influence the results of acoustic musical traditions recorded. This study attempts to understand how different concepts and procedures of production music can influence the acoustic outcome of the sound recordings and, consequently, the musical-aesthetic structure of events transmitted by oral tradition in the state of Pernambuco. Thus, it is composed of bibliographic research on the main scientific productions of audio technology in ethnomusicology, field research with techniques of interviews, questionnaires and direct observation of contexts and important people in music production and oral tradition music in the State. Another important aspect for research was the experience gained over many years of work in ethnomusicology and audio technology, in addition to daily work in the Centro de Difusão e Realizações Musicais SESC - Casa Amarela (PE - Brasil) aimed mainly to Brazilian classical music and Brazilian oral tradition music. This study showed that the phonographic production process can influence the acoustic outcome of oral tradition music, providing differences between the sound of performance context and the sound recorded on media. Inappropriate concepts for the production of this type of music seems to contribute, indirectly, to the occurrence of changes in social structures of these events. Thus, the phonographic processes constitute an important topic of study for ethnomusicology calling attention to issues of changes in music after a production process beyond show gaps in the discipline about issues of power and relevance related to music production. Finally, it was possible to conclude that physical or conceptual factors in the production process of the oral tradition music influence it, sometimes in irreversible form in both artistic and cultural as socio-political and philosophical point of view. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Durante todo o século XX a tecnologia de áudio contribuiu muito para o desenvolvimento da etnomusicologia. Inicialmente com a criação do fonógrafo e de técnicas de registro sonoro, possibilitando o desenvolvimento dos arquivos fonográficos e, posteriormente, com a crição de tecnologias que apresentassem melhor qualidade sonora, menor custo e conceitos mais adequados aos novos paradigmas da disciplina, mesmo sabendo que até meados do século XX a etnomusicologia não apresentava esta denominação, orientação metodológica ou abordagem científica. Apesar da importante contribuição da tecnologia de áudio para a etnomusicologia, observa-se que os processos fonográficos podem influenciar os resultados acústicos de tradições musicais gravadas. Este trabalho busca compreender como diferentes conceitos e procedimentos de produção fonográfica podem influenciar o resultado acústico dos fonogramas e, conseqüentemente, a estrutura estético-musical de manifestações transmitidas por tradição oral no Estado de Pernambuco. Para tanto, é composto de pesquisa bibliográfica sobre as principais produções científicas em tecnologia de áudio na etnomusicologia, pesquisa de campo com técnicas de entrevistas, questionários e observação direta de contextos e pessoas importantes da produção musical e da música de tradição oral no Estado. Outro aspecto importante para a realização da pesquisa foi a experiência adquirida ao longo de alguns anos de trabalho em etnomusicologia e tecnologia de áudio, além do trabalho diário no Estúdio do Centro de Difusão e Realizações Musicais do SESC - Casa Amarela (PE - Brasil), voltado, principalmente, para música erudita brasileira e música brasileira de tradição oral. Este trabalho demonstrou que o processo de produção fonográfica pode influenciar os resultados acústicos de manifestações de tradição oral, propocionando diferenças entre a sonoridade do contexto de performance e a sonoridade da mídia. Assim, conceitos impróprios para a produção deste tipo de música parecem contribuir, indiretamente, para a ocorrência de mudanças nas estruturas sociais destas manifestações. Dessa forma, os processos fonográficos representam um importante tópico de estudos para a etnomusicologia alertando para questões de mudanças na música após um processo de produção, além de evidenciar lacunas na disciplina sobre questões de poder e pertinência relacionadas à produção musical. Finalmente, foi possível concluir que fatores físicos ou conceituais do processo de produção da música de tradição oral a influenciam, por vezes, de forma irreversível tanto do ponto de vista artístico-cultural quanto sócio-político e filosófico.

Apomixis maintains heterosis and avoids transmission of systemic pathogens which accompany vegetative propagation of cassava. An embryonic study of cleared ovules of two cassava clones in toto showed them to be of aposporic nature. Cytogenetic analysis of the two clones revealed an aneuploid structure (2n + 1) in apomictic individuals, whereas it was 2n in the sexually reproduced plants.A Apomixia mantém a heterose e evita a transmissão de patógenos sistêmicos que acompanham a propagação vegetativa da mandioca. Um estudo embriônico de ovos clareados de dois clones de mandioca in toto mostrou que eles são de natureza apospórica. A análise citogenética dos 2 clones revelou uma estrutura aneuploide (2n + 1) em indivíduos apomíticos, ao passo que era 2n em plantas reproduzidas sexualmente.

Resumo Parte da narrativa sobre as comemorações em torno dos 500 anos de nascimento de Conrad Gesner (1516-1565), com ênfase nas experiências vividas no International Congress Conrad Gessner, realizado em junho de 2016 em Zurique, Suíça. No contexto deste fórum de especialistas, identifica o perfil dos Estudos Gesnerianos, com destaque para as pesquisas ligadas à faceta bibliográfica do polímata suíço. A partir das celebrações de 2016, realiza um percurso histórico-retrospectivo ao Séc. XVI para situar e discutir, de forma preliminar, dois aspectos subjacentes ao gesto bibliográfico Gesneriano: método e implicações epistemológicas. Conclui que dimensão histórico-interpretativa da informação, que perpassa pelo gesto e método bibliográfico Gesneriano, não pode ser negligenciada para uma compreensão retrospectiva, crítica e ao mesmo tempo atual do campo informacional.