Caderno de encargos tipo para obras de pavimentação de estradas municipais

Com a recente entrada em vigor do novo acervo normativo nacional que inclui a normalização europeia e a sujeição ao sistema de atestação da conformidade dos agregados, dos betumes e das misturas betuminosas, permitindo a aposição da marcação «CE» é necessário adaptar os cadernos de encargos para obras de pavimentação aos requisitos da normalização europeia, que passa pelo cumprimento das novas normas de produto e aplicação dos novos métodos de ensaio. Assim, o objectivo deste trabalho é elaborar um caderno de encargos tipo adequado aos principais tipos de misturas utilizadas nas obras de pavimentação da rede viária municipal, com base no novo acervo normativo nacional e no caderno de encargos tipo obra promovido pela administração rodoviária, Estradas de Portugal (EP). Apresenta-se neste documento o enquadramento geral da normalização europeia relativamente aos agregados, ligantes e misturas betuminosas e faz-se a síntese das características dos materiais constituintes das misturas não ligadas e de misturas betuminosas de utilização generalizada nas obras de pavimentação das Autarquias Portuguesas. Descrevem-se ainda as condições de execução das camadas constituintes dos pavimentos e respectivos critérios de aceitação e rejeição, bem como o tipo de ensaios e frequências para o controlo de qualidade das misturas. Finalmente é feita uma caracterização das condicionantes das obras de pavimentação municipais e uma avaliação aos requisitos e ensaios relativos ao controlo de qualidade dos materiais e misturas apresentadas, com vista à sua integração em caderno de encargos tipo municipal

Transition of athletes in sport career: from theory to evaluation

Este trabalho analisa a transição dos atletas no desporto, propondo um modelo compreensivo da transição desportiva e um instrumento de avaliação para analisar as transições desportivas dos atletas ao longo da carreira desportiva. Assim, do ponto de vista conceptual descreve-se o Modelo Interativo de Adaptação Humana à Transição Desportiva, que entende este fenómeno como um processo constituído pelos seguintes fatores: (a) circunstâncias da transição desportiva, (b) processos de avaliação cognitiva, (c) respostas ocorridas durante a situação de transição, e (d) resultado final da situação de transição. De seguida, é proposto um guião de entrevista para avaliar a transição desportiva, avaliando seis dimensões: (a) situação de transição, (b) recursos externos disponíveis, (c) mudanças enfrentadas, (d) processos de avaliação cognitiva, (e) respostas psicológicas, fisiológicas e comportamentais, e (f) resultado final da adaptação desportiva. A conjugação de modelos teóricos e instrumentos de avaliação acerca da transição desportiva podem ajudar a compreender este fenómeno.This work analyzes the transition of athletes in sports, proposing a comprehensive model about career transition and an instrument to evaluate the transitions of athletes throughout their careers. First, it is described the Interactive Model of Human Adaptation to Career Transition, proposing that transition is a process constituted by the following factors: (a) circumstances of the career transition, (b) cognitive appraisal, (c) responses occurred during the career transition, and (d) final result of the career transition. Second, it is proposed an interview guide that evaluates six dimensions: (a) circumstances of the career transition, (b) available external resources, (c) demands faced during the career transition, (d) processes of cognitive appraisal, (e) psychological, physiological and behavioral responses, and (f) final result of career transition. The combination of theoretical models and evaluation instruments about the career transition may help to understand this phenomenon.(undefined

The tracking ability of oil and gas exchanged traded funds (ETFs)

Apesar do vasto reportório de trabalhos existentes sobre Exchanged Traded Funds (ETFs), poucos são aqueles que têm analisado commodities ETFs e a respetiva adequabilidade como substitutos de investimentos diretos em commodities. Para analisar se esta classe específica de ETFs é uma boa alternativa, analisámos uma amostra de 11 ETFs e se seguiam os respetivos benchmarks. Para tal procedemos a uma análise de regressão linear, ao cálculo do tracking error, e uma análise de cointegração, sendo esta última focada na relação de longo prazo entre variáveis. As análises de regressões e tracking error evidenciam uma forte ligação com os benchmarks na maior parte dos ETFs, mas os testes de cointegração apresentam resultados díspares, sugerindo uma relação mais fraca no longo prazo para a maior parte dos ETFs. Por outro lado os ETFs que têm como benchmarks índices de commodities apresentam melhores resultados do que aqueles que seguem as commodities propriamente ditas. O uso de produtos derivados, nomeadamente futuros nestes ETFs, e o facto de os mesmos terem de ser constantemente renegociados (Roll Over) são uma das razões para a diferença de performances entre os ETFs e respetivos benchmarks.Despite the vast literature on Exchanged Traded Funds (ETFs), few are those focused on commodities ETFs and their suitability as a replacement for direct investments in commodities. To examine whether this specific class of ETFs is a good alternative we have analyzed the tracking ability of a sample of 11 ETFs and their respective benchmarks. To this end, we have performed a linear regression analysis, a tracking error analysis, and a cointegration analysis, the latter being focused on the long-term relationship. Regressions analyses and tracking error show a strong relationship in most ETFs, but cointegration tests show uneven results, suggesting a weaker relationship in the long run between ETFs and their benchmark. On the other hand the ETFs that follow benchmarks indexes have better results than those who follow the commodities themselves. The use of derivative products such as futures in these ETFs, and the fact that those must be constantly renegotiated (Roll Over) are one of the reasons for the difference in performance between ETFs and their benchmarks

Ashbya gossypii riboflavin overproducing strains are highly susceptible to light-induced oxidative DNA damage

Microbiotec'17 - Congress of Microbiology and Biotechnology 2017Background The overproduction of riboflavin by Ashbya gossypii, which is one of the most distinctive traits of this filamentous hemiascomycete, is triggered by oxidative stress [1]. In turn, riboflavin is a strong photosensitizer that upon irradiation with light has been shown to generate reactive oxygen species (ROS) and induce oxidative DNA damage in mammalian cells [2-3]. Envisioning a better understanding of this A. gossypii trait, here we investigated whether riboflavin overproduction is associated with increased DNA damage. [...]Study supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) (Post-Doc grant to T. Q. Aguiar), BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte, Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124FEDER-027462) and PhD grant PD/BD/113812/2015 to R. Silva.info:eu-repo/semantics/publishedVersio

‘Escapando de la clase tradicional’: the escape rooms methodology within the spanish as foreign language classroom

  The escape games or the so-called escape rooms industry is booming nowadays. Due to the fact that this type of live-action team-based games (Nicholson, 2016) require a great deal of communication and critical thinking, it is quite easy to think of its application in education. This paper aims at discussing how to use escape room concepts for educational purposes and, more specifically, in Spanish as Foreign Language (SFL) classroom. Moreover, it is also our aim to present a case study in which students were invited to both create and participate in an escape room. Therefore, we will be focusing on escape room design applied to the teaching of the SFL setting, taking into consideration game narratives, puzzle types and rooms organization aspects. By following an ethnographic methodological approach, a case study was undertaken in which the following data-collection tools were used: a) questionnaires to figure out students’ perceptions on escape rooms and on the influence of escape room methodologies onto the development of skills; b) field notes, pictures and videos collected during the application of the escape room activities. The main results show that students considered both escape rooms catered for the development of 21st-century skills. Keywords: escape room methodology; gamification; Spanish as a foreign languag

Process engineering of liver cells for drug testing applications

Dissertação para obtenção do Grau de Doutor em BioengenhariaThe primary culture of human hepatocytes is a requirement in drug development tests. This application is currently hampered by two problems: the limited proliferation of the hepatocytes and the rapid loss of liver-specific phenotype of these cells, when cultured in vitro. This thesis aimed at minimizing this latter issue by cultivating hepatocytes, as spheroids, in fully controlled bioreactors. The state of the art of the primary cultures of hepatocytes is reviewed in Chapter 1, after a brief introduction to the liver physiology the drug development process. The improvement of the bioreactor cultures of hepatocyte spheroids was initially done using freshly isolated rat hepatocytes; the effects of alginate microencapsulation, perfusion culture and their synergy on the maintenance of the hepatocyte spheroids liver-specific phenotype were assessed in Chapters 2 and 3; it was concluded that the perfusion culture and alginateencapsulation had a positive synergic effect on such hepatic phenotype. The perfusion bioreactor developed in Chapter 3 was used in Chapter 4 for the extended culture of freshly isolated human hepatocytes, as spheroids, from three different donors. These cultures responded to repeated dose drug treatments as expected from mature and differentiated hepatocytes, in up to 4 weeks culture time. In Chapter 5, human embryonic stem cell-derived hepatic progenitors were cultured as spheroids and further differentiated into hepatocyte-like cells; the differential expression of hepatic genes between this spheroid population and a monolayer differentiated hepatocyte-like cell population showed a more efficient differentiation under spheroid culture. The bioengineering improvements of this thesis, as well as the future work, were discussed in Chapter 6. This thesis has led to the establishment and validation of primary cultures of hepatocyte spheroids, in perfusion bioreactors, which can be used for long-term, repeated dose tests in drug development

Contributes for the development of Ashbya gossypii as a cell factory

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Ashbya gossypii is a filamentous Saccharomycete long known by the scientific and industrial communities, first as a cotton pathogen and subsequently as a riboflavin overproducer. Its industrial relevance combined with its high genetic similarity with Saccharomyces cerevisiae promoted the development of a significant molecular and in silico toolbox for its genetic engineering. This, together with the increasing knowledge of its genome, transcriptome and metabolism has helped designing effective metabolic engineering strategies for optimizing riboflavin production, and also for developing new A. gossypii strains for novel biotechnological applications [1]. Here, we will address our main contributes for the development of A. gossypii as a cell factory organism, by presenting an overview of the most representative outputs from our research [referenced in 1, 2]. Envisioning its exploration as a recombinant protein producer, our main efforts focused on the characterization of the A. gossypii protein secretory pathway at the genomic, transcriptomic and proteomic levels [2]. Based on experimental observations and on data from omic analyses, a hydrolytic enzyme, invertase, was deduced to be natively secreted by A. gossypii and molecularly characterized. The N-glycosylation pattern of the proteins natively secreted by A. gossypii was also characterized, as well as the recombinant production by this fungus of secreted proteins from different fungal origins. Among these, the β-galactosidase from Aspergillus niger was expressed in A. gossypii under the regulation of several native and heterologous promoters, presenting the highest extracellular production levels. [...]info:eu-repo/semantics/publishedVersio

New biotechnological applications for Ashbya gossypii: Challenges and perspectives

The filamentous fungus Ashbya gossypii has long been considered a paradigm of the White Biotechnology in what concerns riboflavin production. Its industrial relevance led to the development of a significant molecular and in silico modeling toolbox for its manipulation. This, together with the increasing knowledge of its genome and metabolism has helped designing effective metabolic engineering strategies for optimizing riboflavin production, but also for developing new A. gossypii strains for novel biotechnological applications, such as production of recombinant proteins, single cell oils (SCOs), and flavour compounds. With the recent availability of its genome-scale metabolic model, the exploration of the full biotechnological potential of A. gossypii is now in the spotlight. Here, we will discuss some of the challenges that these emerging A. gossypii applications still need to overcome to become economically attractive and will present future perspectives for these and other possible biotechnological applications for A. gossypii.This work was support by Fundação para a Ciência e a Tecnologia (FCT), Portugal, through the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER006684) (Post-Doc fellowship to T. Q. Aguiar), BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte, and PhD Grant PD/BD/113812/2015 toR.Silva.info:eu-repo/semantics/publishedVersio

Why does uridine supplementation properly rescues the growth of Ashbya gossypii uracil auxotrophs, but not uracil?

The use of auxotrophies as a tool for genetic modification of microbial strains is widely employed in microbiology laboratories. However, there are some recognized problems associated with their use, such as the fact that it is unclear how much supplementation is required for each auxotrophy and microorganism1. Among the auxotrophies, one of the most used is that for uracil. In this case, the strains require the supply of exogenous uracil to compensate their nutritional deficiency. However, in some studies exogenous uridine is used instead of uracil. The flavinogenic A. gossypii Agura3 strain is unable to grow at the same level of the parent strain when the medium is supplemented with uracil alone, being necessary the addition of uridine to overcome this effect2. A similar effect was also reported for other flavinogenic fungi, such as Pichia guilliermondii (Candida guilliermondii) 3. Given the importance of these uracil auxotrophic strains, it is of extreme pertinence to elucidate the determinants behind this inadequacy of uracil to rescue the growth of flavinogenic uracil auxotrophs. Therefore, in this work we investigated the capability of the intermediates of the salvage pathways of pyrimidine ribonucleotides to rescue the growth of A. gossypii Agura3 and verified that uridine is the most adequate for growth supplementation. Based on these results, a hypothesis identifying the potential limiting step of this pathway in A. gossypii is proposed.Acknowledgments to FCT, Portugal: strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) (Post-Doc fellowship to TQ Aguiar), BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by FEDER under the scope of Norte2020 - Programa Operacional Regional do Norte, and PhD grant PD/BD/113812/2015 to R Silva

Magnetic systems for regenerative medicine

[Excerpt] Over the last decade, magnetic-based systems have made remarkable breakthroughs in the field of tissue engineering and regenerative medicine. The ability for contactless manipulation of magnetic responsive biomaterials, or even living cells, has been leveraged to devise innovative concepts that are widening the available bioengineering design space that can be explored in this multidisciplinary field. From the fabrication of cellular constructs with bioinspired patterns and hierarchical structures up to the concepts of levitational bioassembly, magnetic systems are enabling to engineer 3D tissues that better recapitulate the complex biophysical and biological cues of their native counterparts. Moreover, the inherent magnetic responsiveness of this living systems is being explored as mechanical and electrical nanotransducers to further stimulate cell functions, not only in vitro but also in vivo. Remarkably, recent advances in the convergence of microfabrication technologies with magnetic materials is also opening prospects to further fabricate advanced living microrobots and microphysiological systems with new added functionalities. Due to their good track record of biological tolerance and biodegradability, iron oxide-based nanoparticles remain the first choice of (superpara)magnetic nanomaterials, but new variants and combinations of nanomaterial are being increasingly explored in this field. Altogether, magnetic systems are contributing in multiple ways to boost the regenerative potential of bioengineered constructs and may lead to the development of in vitro tissue/organ models with improved physiological relevance. [...