6,710 research outputs found

    “Landscape and Heritage of Hydroelectricity in Portugal”

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    Hydroelectric power plants provided countries with scarcity of coal, such as Portugal, with a vital source of energy for the production of electricity in large quantities. Therefore, since the late 19th century the use of waterfalls as producers of electric power was a topic of study and interest among engineers and the matter was regularly discussed at the Association of Portuguese Civilian Engineers. The great hydroelectric power plants, considered by many as the cathedrals of the second industrial revolution are an important industrial heritage which is important to value and appreciate. Hydroelectricity also gave origin to new landscapes and the problem today regards the management of this new landscape and the construction of new patrimonial values

    Asserting the Portuguese Civil Engineering Identity: the Role Played by the École des ponts et chaussées

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    This paper focuses on the Portuguese engineers who returned to Portugal following a training period at École des Ponts et Chaussées, in Paris between 1831 and 1870. During the 19th century, in spite of the creation of engineering schools, such as the Military Academy (1836), the Polytechnic School of Lisbon (1837), the Polytechnic Academy of Oporto (1837), the number of engineers to ensure the planning and the direction of the public works remained insufficient. Moreover, the education provided by these schools granted almost no room for fieldwork. Like in the other European States, some Portuguese engineers tried to complete their training in foreign countries, in particular by attending schools such as the École des Ponts et Chaussées de Paris. The studies which they carried out as well as the projects and the “missions d’études” enabled them to intervene in various areas, from the construction of bridges and railways to agricultural hydraulics on their return to Portugal. Following their return, these engineers played an important role both in the transfer of knowledge as well as in updating Portuguese engineering. They designed and directed various public works and transmitted to their subordinates the most modern methods of planning and construction of roads, railways and seaports. In addition, they were appointed to political and administrative positions in particular within the Ministério das Obras Públicas, Comércio e Indústria created in 1852, in the context of which they had to evaluate, authorize or reject various engineering projects. Finally, some were appointed professors in Portuguese engineering schools where they taught new theories, methods and practices of civil engineering which they had learnt in Paris or during trips abroad

    Equilibrium Bid-Ask Spread of European Derivatives in Dry Markets

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    In the framework of incomplete markets, due to the non-existence of trade at some points in time, and using a partial equilibrium analysis, we show how the bid-ask spread of an European derivative is generated. We also ¯nd conditons for the existence of the spread. These conditions concern the market structure of the maret-makers, which can be a oligolopoly with price competition or a monopoly, as well as the riskaversion of the demand and supply of the market.

    Dry Markets and Statistical Arbitrage Bounds for European Derivatives

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    We derive statistical arbitrage bounds for the buying and selling price of European derivatives under incomplete markets. In this paper, incompleteness is generated due to the fact that the market is dry, i.e., the underlying asset cannot be transacted at certain points in time. In particular, we re¯ne the notion of statistical arbitrage in order to extend the procedure for the case where dryness is random, i.e., at each point in time the asset can be transacted with a given probability. We analytically characterize several properties of the statistical arbitragefree interval, show that it is narrower than the super-replication interval and dominates somehow alternative intervals provided in the literature. Moreover, we show that, for su±ciently incomplete markets, the statistical arbitrage interval contains the reservation price of the derivative.

    Dry Markets and Superreplication Bounds of American Derivatives

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    This paper studies the impact of dry markets for underlying assets on the pricing of American derivatives, using a disrete time framework. Dry markets are characterized by the possibility of non-existence of trading at certain dates. Such non-existence may be deterministic or probabilistic. Using superreplicating strategies, we derive expectation representations for the range of arbitrage-free values of the dervatives. In the probabilistic case, if we consider an enlarged filtration induced by the price process and the market existence process, ordinary stopping times are required. If not, randomized stopping times are required. Several comparisons of the ranges obtained with the two market restrictions are performed. Finally, we conclude that arbitrage arguments are not enough to define the optimal exercise policy.American derivatives, pricing, incomplete markets, dry markets, superreplication, randomized stopping times, strong duality

    Molecular analysis of anterior endoderm during Xenopus development: a funtional and genomic approach

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    Tese de doutoramento em Biologia (Biologia do Desenvolvimento), apresentada à Universidade de Lisboa através da Faculdade de Ciências, 2008Fundação para a Ciência e Tecnologia (FCT), (SFHR/BD/10035/2002

    Plasma membrane-specific interactome analysis reveals calpain 1 as a druggable modulator of rescued Phe508del-CFTR cell surface stability

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    Cystic fibrosis (CF) is a genetic disease caused by mutations in the gene encoding CF transmembrane conductance regulator (CFTR), a chloride channel normally expressed at the surface of epithelial cells. The most frequent mutation, resulting in Phe-508 deletion, causes CFTR misfolding and its premature degradation. Low temperature or pharmacological correctors can partly rescue the Phe508del-CFTR processing defect and enhance trafficking of this channel variant to the plasma membrane (PM). Nevertheless, the rescued channels have an increased endocytosis rate, being quickly removed from the PM by the peripheral protein quality-control pathway. We previously reported that rescued Phe508del-CFTR (rPhe508del) can be retained at the cell surface by stimulating signaling pathways that coax the adaptor molecule ezrin (EZR) to tether rPhe508del–Na+/H+-exchange regulatory factor-1 (NHERF1) complexes to the actin cytoskeleton, thereby averting the rapid internalization of this channel variant. However, the molecular basis for why rPhe508del fails to recruit active EZR to the PM remains elusive. Here, using a proteomics approach, we characterized and compared the core components of wt-CFTR– or rPhe508del–containing macromolecular complexes at the surface of human bronchial epithelial cells. We identified calpain 1 (CAPN1) as an exclusive rPhe508del interactor that prevents active EZR recruitment, impairs rPhe508del anchoring to actin, and reduces its stability in the PM. We show that either CAPN1 downregulation or its chemical inhibition dramatically improves the functional rescue of Phe508del-CFTR in airway cells. These observations suggest that CAPN1 constitutes an attractive target for pharmacological intervention, as part of CF combination therapies restoring Phe508del-CFTR function.This work was supported by a center grant UID/MULTI/04046/2019 to BioISI and project PTDC/BIA-CEL/28408/2017 and IF2012 to PM, both from FCT, Portugal. AMM was recipient of fellowship SFRH/BD/52490/2014 from BioSYS PhD programme PD65-2012, and PB of fellowship SFRH/BPD/94322/2013.N/

    NEETin with ICT

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    Science and Technology Advisory Council (STAC) outlines that 49% of EU citizens identified “job creation” and 33% identified “education and skills” as the top priorities for science and technology innovation over the next fifteen years. Both documents justify the needs in Europe for the ICT field especially for the NEET (not in education, employment or training) citizens. On the other hand, Grand Coalition for Digital Jobs (GC4DJ) in Europe identifies: the training and matching digital jobs; certification; innovative learning and teaching; mobility; awareness raising; increasing effectiveness of education; increasing equity and producing positive impact in the economy, as a priority for European countries. NEETin is a project directed to NEET citizens, to be developed by Higher Education Institutions, VET providers and Enterprises in order to help to overcome a social European dimension through lifelong learning. By creating a Joint Vocational Education Training in Digital Competences in a collaboration between VET providers and the Enterprises, widening the access to higher education, in an innovative student-centred learning model to apply in a European level, we aim to contribute to improve the quality of Education. Through this certified JVET, NEET citizens will develop their digital skills and the success of employability of these learners will be enhanced.info:eu-repo/semantics/publishedVersio
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