Browsing by Issue Date, starting with "2022-06-06"
Now showing 1 - 6 of 6
Results Per Page
Sort Options
- Environmental sustainability in companies: the circular economyPublication . Orvalho, Luísa; Oliveira, Diogo; Silva, PedroIt is increasingly essential to raise awareness and to understand the Circular Economy and the 17 Sustainable Development Goals of the United Nations 2030 Agenda for Sustainable Development at the individual and organizational levels of society. The scope of this article comprises the main concepts derived from sustainable development, such as a Circular Economy model, based on the 2030 Agenda; covers the way they are applied and presented to society, focusing on different types of ecoinnovation to promote competitiveness; covers the impact of the Coronavirus pandemic on the goals set by governments; and presents the case of the application of the model in the city of Porto, making it a city that moves towards the Circular Economy
- O reflexo de Robert Altman e de Martin Scorsese no cinema de Paul Thomas AndersonPublication . Gonçalves, Gesiane Vieira Matos; Capucho, Carlos Alberto BarrosoNa história do cinema podemos considerar, mesmo nos seus tempos mais primitivos, o pioneirismo de muitos realizadores que marcaram e modificaram a linguagem do cinema mundial. Desta forma, observamos no cinema contemporâneo a influência cinematográfica de muitas obras do passado, ainda que as possibilidades tecnológicas estejam completamente inseridas nas criações atuais. Dentro das mudanças ocorridas em todo o percurso do cinema, assim como todos os acontecimentos revolucionários que permitiram a evolução desta arte, a presença da influência artística levanta algumas questões sobre a originalidade e técnicas utilizadas na criação dos filmes. O realizador como artista utiliza a sua criatividade e ideias fílmicas estruturadas de uma forma única num processo de união das partes que resulta em trabalhos inovadores. O presente estudo tem como principal objetivo a reflexão do cinema como forma de arte e as linhas de influências artísticas do passado. Entretanto, refletir sobre a influência cinematográfica implica em perceber as referências inseridas em algumas obras como forma de seguir um padrão artístico ou de facto o cinema contemporâneo está assente na imitação. Este trabalho baseia-se em estudos bibliográficos, filmográficos e análise empírica e propõe a observação de registos fílmicos provenientes de obras dos realizadores Robert Altman e Martin Scorsese contextualizadas no cinema do realizador norteamericano Paul Thomas Anderson. A investigação assenta na existência da influência artística cinematográfica com base no argumento de E.H. Gombrich no livro A História da Arte (2006) que enfatiza os processos criativos dos artistas e suas influências, assim como no livro Art and Illusion (2000) do mesmo autor, que defende a influência artística como um esquema seguido de correção.
- Flow-based methods for iodine and iron quantification in food-related, water, and blood serum samplesPublication . Miranda, Joana Lopes Abreu; Rangel, António Osmaro Santos Silva; Mesquita, Raquel Beatriz Ribeiro deIn this thesis, the use of different flow systems was exploited for developing new methodologies for miniaturization of the analysis of complex matrix samples (food-related, water and biological samples). The main purpose was to devise methodologies able to perform in-line the necessary sample treatment operations, reducing the operator influence and reagents manipulation, and tentatively using greener processes. Under this program, a flow-based spectrofluorimetric chip manifold method for the iodine determination in food-related samples, was developed. The use of a multi-syringe enabled the automation of the Sandell-Kolthoff reaction, leading to a lower operator influence and reagents consumption and manipulation. An in-line oxidation process was implemented to analyse samples with organo-iodine containing compounds; this implied to eliminate interferences and decomposition of organo-iodine compounds in supplement pills and seaweed samples (Chapter 3). The developed method was effectively applied to the iodine determination in salt, food supplements (algae), seaweed and pharmaceutical samples, which are examples of intake forms of iodine. The proposed manifold, combined with the fluorometric reaction, made this method more sensitive than the classic approach of the Sandell-Kolthoff reaction and presents some advantageous over previously described flow methods, namely in terms of a wider dynamic concentration range. The method allowed to determine iodine within a range of 0.20 – 4.0 µmol/L, with or without the in-line UV digestion, with a limit of detection of 0.028 µmol/L and 0.025 µmol/L, respectively. In Chapter 4, an hexadentate 3-hydroxy-4-pyridinone (3,4–HPO) ligand was used as a chromogenic reagent for the spectrophotometric quantification of iron(III) in fresh and sea waters. A method based on a micro sequential injection lab-on-valve (µSI-LOV) system in a solid phase spectrometry (SPS) mode, is described. To implement SPS, a packed column of nitrilotriacetic acid superflow resin (NTA) in the flow cell, was used, consequently eliminating the sample matrix. Furthermore, the possibility to perform of an analytical curve resorting to just one standard was demonstrated. The consumption of the hexadentate 3,4–HPO ligand was about 30 µg per determination and the effluent production lower than 2.5 mL. The dynamic concentration range was 0.45 – 9.0 µmol/L, with a limit of detection of 0.13 µmol/L and limit of quantification 0.43 µmol/L. The proposed µSI-LOV-SPS methodology was successfully applied to river, ground, estuarine, tap, and sea waters. The evaluation of the analytical performance of different 3,4–HPO bidentate chelators, as chromogenic reagents in the determination of iron(III), using a µSI system, in aqueous samples, was described in Chapter 5. In Chapter 6, a bidentate 3-hydroxy-4-pyridinone ligand was anchored to sepharose beads and used as chromogenic reagent for the spectrophotometric quantification of non-transferrin-bound iron (NTBI). By employing a micro sequential injection lab-on-valve (µSI-LOV) system with a SPS technique, it was possible to eliminate the interference of the sample matrix and quantify iron(III) directly on the beads surface. The dynamic concentration range was 1.62 – 7.16 µmol/L, with a limit of detection of 0.49 µmol/L and limit of quantification 1.62 µmol/L. The proposed µSI-LOV-SPS method, in Chapter 6, was a contribution to the development of an automated method for the quantification of the NTBI in serum samples.
- Celebration of the 5th Centenary of Fernão de Magalhães's circumnavigation voyagePublication . Orvalho, Luísa; Sousa, João; Brito, LucasIn this article we intend to demonstrate the importance of the circumnavigation voyage for the advancement of science and technology in the 16th century, the research and innovation projects carried out within the scope of the 5th Centenary celebrations, project the “Magalhães feat in the future, as pillars of a new international agenda” and to compare the globalization produced at the time of the Discoveries with globalization as a modern phenomenon that emerged with the evolution of the new means of communication.
- Indemnização por ilegalidades cometidas em procedimentos pré-contratuais : o enigmático artigo 7º n.º 2 do Regime da Responsabilidade Civil Extracontratual do Estado e demais Entidades PúblicasPublication . Gaspar, Sandra Daniela da Rocha; Gomes, Pedro Miguel dos Santos Silva CerqueiraO presente trabalho tem por escopo analisar a obrigação de indemnização das entidades adjudicantes por violação de normas no âmbito do procedimento de formação dos seus contratos, prevista no n.º 2 do art. 7º do Regime Geral da Responsabilidade Civil Extracontratual do Estado, aprovado em anexo à Lei 67/2007 de 31/12. O preceito em apreço é o resultado das imposições do Direito da União Europeia no campo da política da contratação pública, com o fito de alcançar um mercado comum, aberto e de livre concorrência. Deste modo, embora o artigo citado esteja inserido no Regime da Responsabilidade Civil Extracontratual do Estado, a verdade é que o mesmo, por influência do Direito da União Europeia, contém um regime próprio que se distancia do regime geral da responsabilidade civil extracontratual do Estado. Assim, procedemos à sua interpretação à luz do regime previsto nas denominadas Diretivas Recursos, ou seja, Diretiva n.º 89/665/CEE, do Conselho de 21/12/1989 e a Diretiva n.º 92/13/CEE, do Conselho de 25/02/1992. Concomitantemente é analisado o regime da responsabilidade civil extracontratual do Estado por violação do Direito da União Europeia seguindo-se a basta jurisprudência emanada pelo Tribunal de Justiça da União Europeia. Por fim é analisada a indemnização a conceder ao lesado, o tipo de danos e respetiva ressarcibilidade enquanto interesse contratual positivo ou negativo e ainda a perda de chance.
- Can the trade-off theory better match empirical evidence by implementing mean reverting earnings? A theoretical study on the trade-off theoryPublication . Hjellegjerde, Oddvar; Silva, NunoThe traditional trade-off theory predicts a positive relation between earnings and leverage ratio, contradictory to empirical evidence which suggests a negative relationship between the two. The objective of this dissertation is to analyse whether introducing mean reverting earnings to the traditional trade-off theory turns the model results more in line with empirical evidence. In the dissertation, I implement the Sarkar and Zapatero (2003) model, which considers mean reverting earnings before interest, taxes and depreciations in a setup similar to the proposed by Leland (1994). I use this model to calculate the optimal leverage ratio. The original input parameters presented by Sarkar and Zapatero (2003) were considered and equal results were obtained. The model was solved numerically for the optimal default barrier, optimal coupon level, and finally for the optimal leverage ratio. Furthermore, different initial earnings levels, different speeds of mean-reversion and different mean earnings-levels were considered to observe how the model handles different input values. As argued by Sarkar and Zapatero (2003), the consideration of mean-reversion leads to a negative relationship between the optimal leverage ratio and earnings, which is in line with empirical evidence. This result should change the generalized idea that the trade-off theory is not consistent with data regarding the earnings-leverage relationship.