1,132 research outputs found

    Should we Distinguish Between Static and Dynamic Long Run Equilibrium in Error Correction Models?

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    This paper shows that there is no theoretical foundation to distinguish between static and dynamic long run equilibrium in error correction models with deterministically cointegrated variables, and so, that the so-called dynamic homogeneity restriction aimed at guaranteeing that the two solutions coincide, also lacks a theoretical justification. Examples in which dynamic homogeneity cannot hold are also discussed.

    Higher education institutions and international students’ hindrances: a case of students from the African Portuguese-speaking countries at two European Portuguese universities

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    We present a study to comprehend if the support given by higher education institution (HEI) to international students coming from the PortugueseSpeaking African Countries meets their academic and social hindrances. Our starting point was a set of semi-structured interviews focused on the perspectives of these students, their Professors and Course Directors as well as on the perspectives of HEI’ staff. Despite findings indicate a positive institutional support, it seems there is still much to do in order to do it properly with these students. These different perspectives will allow us to reflect on the impact that those actions/resources have on the path of students from Portuguese-Speaking African Countries and to systematize suggestions to enhance their experiences in HE.info:eu-repo/semantics/publishedVersio

    Duodenal Subepithelial Lesion? An Unexpected Endoscopic Ultrasound Finding

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    Anaerobic digestion of enzymatically treated dairy cow effluent [Resumo]

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    ABSTRACT: In Portugal, cattle production increased up to 91,000 t in 2016 (EUROSTAT, 2016) and has been contributing to the increase of methane emissions into the atmosphere. As an appropriate process for the treatment of organic effluents, anaerobic digestion is ideal to minimize this negative impact since it provides the agricultural and energetic valorisation of the substrate through the production of digestate and biogas. Heating, cooling and electricity supply constitute different applications for this energy carrier gas with a relevant social, environmental and economic importance, mainly for the region and neighbouring areas where it is produced. Dairy cow effluent is an example of lignocellulosic biomass, whose recalcitrant compounds, such as lignin and phenols, must be previously hydrolysed and made available for subsequent anaerobic digestion. The use of laccase and hemicellulase may be of great interest as pre-treatment for a wide range of pollutant compounds of effluents.N/

    Anatomy of the disease-related Dis3L2 ribonuclease: dissecting the amino acids responsible for substrate specificity

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    Ribonucleases are enzymes which perform the processing and degradation of all types of RNA, being critical for the tight post-transcriptional regulation of gene expression. Three homologues from the RNase II/RNB family of exoribonucleases are found in eukaryotes: Dis3, Dis3L1, and Dis3L2. The first two associate with the RNA exosome, while Dis3L2 participates in an alternative degradation pathway, depending on 3’-uridylation by terminal uridylyl transferases and poly(U) polymerases. The first insights on protein–RNA interactions were obtained analysing the mouse Dis3L2–oligo(U) structure, supporting the distinctive preference of Dis3L2 for uridylated substrates. To date, Dis3L2 has already been associated with cellular processes as relevant as RNA surveillance, cell proliferation and differentiation. Human DIS3L2 defects have been related to several cancers, alongside with Perlman Syndrome, a rare foetal overgrowth disorder, consequently increasing the risk for Wilms Tumour, a malignant kidney tumour commonly affecting children. Nevertheless, much remains unknown about the mechanism of action of Dis3L2 and its peculiar substrate preference. In this work, fission yeast was used as an eukaryotic microorganism model for studying a considerably important ribonuclease in human diseases. Our aim was the identification of particular amino acids potentially crucial for activity and substrate specificity of Schizosaccharomyces pombe Dis3L2 (SpDis3L2), namely those involved in its preference for uridylated substrates. Thus, wild-type and point mutants of SpDis3L2 were overexpressed and purified. A thermal shift assay allowed the improvement of protein stability and enhanced full-length protein purification. Subsequently, the exoribonucleolytic activity of SpDis3L2 versions was analysed over different RNA substrates, using an inactive mutant as control. We uncovered that all tested mutants were active, with several of them differing from the wild-type regarding their level of activity and their preference for uridylated substrates. Therefore, these results pave the way for the analysis of other protein versions with combinations of these point mutations.As ribonucleases são enzimas responsáveis pelo processamento e degradação do RNA, sendo essenciais na regulação pós-transcricional da expressão génica. Em eucariotas, encontramos três homólogos das exorribonucleases da família RNase II/RNB: Dis3, Dis3L1 e Dis3L2. Os dois primeiros associam-se ao exossoma, enquanto a Dis3L2 participa numa via alternativa de degradação dependente da 3’-uridilação por uridilil transferases terminais e poli(U) polimerases. Atualmente, a Dis3L2 já foi associada a processos celulares pertinentes como o controlo de qualidade do RNA, e a proliferação e diferenciação celulares. Defeitos na DIS3L2 humana foram relacionados com vários cancros, bem como com a Síndrome de Perlman, uma doença rara de sobre-crescimento fetal que aumenta o risco para o Tumor de Wilms, um tumor renal geralmente encontrado em crianças. Contudo, ainda muito se desconhece do mecanismo de ação da Dis3L2 e da sua preferência distintiva por substratos uridilados. Usando a levedura de fissão como modelo de microrganismo eucariótico para estudar esta ribonuclease extremamente relevante para doenças humanas, este trabalho pretendeu identificar aminoácidos da Dis3L2 de Schizosaccharomyces pombe (SpDis3L2) potencialmente cruciais para a sua atividade, especificidade de substrato, e, em particular, pela preferência por substratos uridilados. Assim, a SpDis3L2 selvagem e respetivos mutantes pontuais foram sobrexpressos e purificados, após a otimização das condições de purificação para que favorecessem a purificação da proteína no seu estado íntegro. A atividade exorribonucleolítica das versões da SpDis3L2 foi analisada sobre diversos substratos de RNA, tendo-se revelado que, à exceção do mutante inativo usado como controlo, todos os mutantes testados eram ativos. Comparando com a proteína SpDis3L2 selvagem, houve mutantes para os quais se observaram diferenças relativamente ao seu nível de atividade e à preferência por substratos uridilados. Tomando estes resultados em consideração, este trabalho constitui o primeiro passo para que se possa, futuramente, analisar versões desta ribonuclease com combinações destas mutações pontuais

    Innovation and economic growth in Europe in the first decade of the new millennium: Panel data analysis of the Lisbon strategy’s impact

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    The objective of Lisbon Strategy was to make the European Union in the most competitive knowledge-based economy in the entire world, capable of ensuring sustainable economic growth with more and better jobs and greater social cohesion. The strategy highlights the fundamental role of innovation policies so that objectives can be achieved. The reforms include making R&D a top priority, promoting the use of information and communication technologies (ICTs) and increase the investments in education. What this work proposes is an analysis of the relationship between innovation and economic growth in the first decade of the XXI century using a panel of 14 European Union countries that signed the treaty. The main objective is to quantify the impact of the measures of the Lisbon Strategy in the field of innovation. Estimations have been carried out using fixed-effects (FE) and Arellano-Bond GMM estimator. The findings suggest that innovation (through R&D, patents, and education) has a small effect in economic growth during the Lisbon Strategy. With FE, the R&D has a small effect in Gross Domestic Product per capita and with GMM the result is negative. The problem may arise from the time lag between the investments in R&D and education and the emerging of innovation. The economic crisis also contributed to the decrease of investments in innovation and education.O objetivo da Estratégia de Lisboa é tornar a União Europeia na mais competitiva economia baseada no conhecimento em todo o mundo, capaz de garantir um crescimento económico sustentável, com mais e melhores empregos e maior coesão social. A estratégia destaca fundamentalmente o papel das políticas de inovação para que os objetivos possam ser atingidos. As reformas incluem fazer da I&D uma prioridade, promover o uso das Tecnologias de Informação e Comunicação (TIC’s) e aumentar os investimentos em educação. O que este trabalho propõe é uma análise da relação entre inovação e crescimento económico na primeira década do século XXI através de um painel de 14 países da União Europeia que assinaram o tratado. O principal objetivo é quantificar o impacto das medidas da Estratégia de Lisboa em matéria de inovação. As estimativas foram realizadas usando o método de efeitos fixos (FE) e o estimador GMM de Arellano-Bond. Os resultados sugerem que a inovação (através de I&D, patentes e educação) tem um efeito pequeno no crescimento económico durante a Estratégia de Lisboa. Com FE, a I&D tem um pequeno impacto no Produto Interno Bruto per capita e com o GMM o resultado é negativo. Este resultado poderá ser explicado pelo intervalo de tempo que existe entre os investimentos em I&D e educação e o surgir da inovação. A crise económica também contribuiu para a diminuição dos investimentos em inovação e educação

    The application of new technologies in fashion and implementation of additive manufacturing in the apparel industry

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    The most diverse sectors were influenced by the democratisation of 3D printers. This is why fashion designers try to apply 3D printing to their creations and look for a viable way to implement the technique. The adoption of 3D printing on apparel not only brings new advantages but also changes the entire manufacture of the product and the design development, as well as the relationship with the consumer. The application of fashionable printing is still very much focused on accessories and footwear, yet to bring innovation. There is still a need to launch new materials and introduce more technologies, representing what many see as part of the fourth industrial revolution in the context of fashion, where smart or wearable textiles win more and more space in the market, and prosumers increase every day. While the introduction of this technique in the fashion industry is recent compared to the traditional methods of garment manufacturing, there has been significant progress and a growing number of enthusiastic designers who try to develop this type of product. However, while there are many materials designed for printing and designers to develop their parts, there is a recurring problem that translates into the rigidity of the components obtained and, consequently, the lack of comfort and usability. That is why 3D printing has developed more rapidly in the accessory industry (jewellery, bags ...). After extensive research on additive manufacturing technologies and its application in the fashion industry, it was possible to verify that footwear, jewellery, and other accessories were the ones that had better adherence. It was also observed that in the clothing sector the technology is still very much linked to conceptual fashion and that there are several obstacles to the implementation of the technique. It is also clear that there is a long way to go about the feasibility of solutions for the manufacture and the need to find means that allow more flexible and comfortable parts of good quality and with ample movement. It is necessary to have a material innovation that enables the creation of pieces in which comfort, mobility, and flexibility are prioritised since designers do not prioritise only the aesthetic appeal, but also the function and usability of the object. My project aims to address precisely the application of fashionable additive manufacturing and get a new approach on the materials used, the forms and machines for creating textiles and then clothing, to make the daily life of these pieces more viable.Os setores mais diversos foram influenciados pela democratização das impressoras 3D. Por essa razão os designers de moda tentam aplicar a impressão 3D às suas criações e procuram uma maneira viável de implementar a técnica. A adoção da impressão 3D no vestuário não apenas traz novas vantagens, mas também altera todo o fabrico do produto e o método de design, bem como o relacionamento com o consumidor. A aplicação da impressão na moda ainda é muito focada em acessórios e calçado, contudo para trazer inovação, é necessário lançar novos materiais e introduzir mais tecnologias, representando o que muitos consideram parte da quarta revolução industrial no contexto da moda, onde têxteis inteligentes ou vestíveis ganham cada vez mais espaço no mercado e os “prosumidores” aumentam a cada dia. Embora a introdução desta técnica na indústria da moda seja recente em comparação com os métodos tradicionais de fabricação de vestuário, houve um progresso significativo e um número crescente de designers entusiastas que tentam desenvolver este tipo de produto. No entanto, embora existam muitos materiais desenvolvidos para impressão e designers para desenvolver suas peças, há um problema recorrente que se traduz na rigidez das peças obtidas e, consequentemente, na falta de conforto e usabilidade. É por isso que a impressão 3D se desenvolveu mais rapidamente na indústria de acessórios. Após uma extensa pesquisa sobre tecnologias de manufatura aditiva e sua aplicação na indústria da moda, foi possível verificar que calçados, joias e outros acessórios foram os que tiveram melhor aderência. Observou-se também que no setor de vestuário a tecnologia ainda está muito ligada à moda conceitual e que existem vários obstáculos para a implementação da técnica. No entanto há ainda um longo caminho a percorrer em relação à viabilidade de soluções para a confeção e a necessidade de encontrar meios que permitam partes mais flexíveis e confortáveis de boa qualidade e com amplo movimento. É necessário ter uma inovação material que permita a criação de peças nas quais o conforto, o movimento e a flexibilidade sejam priorizados, uma vez que os designers não priorizam somente o apelo estético, mas também a função e usabilidade do objeto. Este projeto visa abordar precisamente a aplicação de manufatura aditiva na moda e obter uma nova abordagem sobre os materiais utilizados, as formas e as máquinas para criação de têxteis e posteriormente vestuário, de forma a tornar mais viável o quotidiano destas peças

    MicroRNAs and target genes involved in E. globulus xylogenesis: in silico prediction and experimental validation

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    Mestrado em Biologia Funcional - Instituto Superior de AgronomiaPortugal is one of the largest producers of pulp and paper derived from Eucalyptus globulus, which makes this a valuable species for the country. Wood is a complex and variable material, and its posttranscriptional regulation knowledge is only beginning. MicroRNAs (miRNA) are small size (21-24nt), endogenous non-coding RNAs, involved in post-transcriptional regulation. MiRBase v20 database encloses thousands of entries, however none from Eucalyptus. In this study we aim to validate E. globulus miRNAs candidates; to predict in silico and validate experimentally the miRNAs targets; and analyze the gene expression of validated targets. Four miRCa-02, miRCa-04, miRCa-08 and miRCa-09 candidates were validated by Northern blot and there in silico prediction revealed 42 target genes. Fourteen predicted target genes were tested through the RLM 5’-RACE methodology, but only three predicted targets were validated (Eucgr.E01509, Eucgr.C01382 and Eucgr.J02113 predicted target genes for miR171, miRCa-04 and miRCa-08, respectively). Expression of these three target genes analyzed by RT-qPCR suggests that the distinct expression levels found may be related with to wood formation in Eucalyptus globulus. For the first time, four Eucalytus miRNAs and their target genes were disclosed and validated by bioinformatic and molecular tools
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