The relevance of the tax effect compared with other dupont model factors in order toxplain the “return on equity” (Listed Companies – France, Germany, Portugal and Spain)

Financial statements provide information that could explain the return on equity. The DuPont extended model identifies five key ratios/indicators that might explain the performance of a company – tax effect, interest burden, earnings before interest and taxes (EBIT) margin, assets turnover and financial leverage. This study aims to analyze the relevance of the tax effect on the “return on equity” (ROE) when compared with the other DuPont model factors. For the purpose of the study, we selected a sample based on listed companies from the stock markets of France, Germany, Portugal and Spain. The number of companies in the sample is 516. The Ordinary Least Square (OLS) method was used to determine the individual impact of each factor on the “return on equity”. According to our findings, the tax effect and the interest burden play the most important role in order to explain the return on equity.info:eu-repo/semantics/publishedVersio

The relevance of the tax effect to explain the "return on equity" (listed companies – France, Germany, Portugal And Spain)

Financial statements provide information that could explain the return on equity. The DuPont extended model identifies five key ratios/indicators that might explain the performance of a company – tax effect, interest burden, earnings before interest and taxes (EBIT) margin, assets turnover and financial leverage. This study aims to analyse the relevance of the tax effect on the "return on equity" (ROE). For the purpose of the study we selected a sample based on listed companies from the stock markets of France, Germany, Portugal and Spain. The number of companies of the sample is 516. The Ordinary Least Square (OLS) method was used to determine the individual impact of each factor on the "return on equity". According to our findings, the tax effect and the interest burden play the most important role in order to explain the return on equity.info:eu-repo/semantics/publishedVersio

Testing Λ\Lambda-Free f(Q) Cosmology

We study a model of Symmetric Teleparallel gravity that is able to account for the current accelerated expansion of the universe without the need for dark energy component. We investigate this model by making use of dynamical system analysis techniques to identify the regions of the parameter space with viable cosmologies and constrain it using type Ia supernova (SnIa), cosmic microwave background (CMB) data and make forecasts using standard siren (SS) events. We conclude that this model is disfavored with respect to $\Lambda$CDM and forthcoming standard siren events can be decisive in testing the viability of the model.Comment: 9 pages, 3 figure

Animal spirits vs contagion: Which one is the main driver of sovereign yields in Europe?

The objective of this paper is to assess the differences between contagion and investors’ risk aversion in terms of their impact on European sovereign bond yields during the financial crisis. This paper evaluates contagion at banking level, as it has the advantage of capturing the exposure of sovereign debt markets to financial sector’s risk and also the contagion between sovereign spreads that occurs through the financial sector channel. The paper analyzes the period from 2008 to 2012 and also the Greek, Portuguese and Spanish bailout periods. The results indicate that the main driver of yields in Europe is risk aversion and not contagion. The main differences between Central and Southern European countries’ yields are explained by risk aversion. This channel has a much stronger impact on the periphery. On the other hand, contagion exerts a similar influence throughout all European countries

Structure of ant-diaspore networks and their functional outcomes in a Brazilian Atlantic Forest

Ants are able to interact with fruits and seeds that are not adapted for ant seed dispersal. In Brazil, several studies show interactions of ants with non-myrmecochorous diaspores; however, few of them have studied the structure of ant-fruit networks. The use of the network approach allows visualising multiple interactions between partners and how they are shaped by the community context. Our study aims to investigate ant-fruit networks as well as quantitative and qualitative dispersal components in a fragment of the Brazilian Atlantic Forest. We investigated the structure of interaction networks, diaspore removal rates, diaspore destination and dispersal distance over two years of observation. We constructed three interaction networks: dry season, rainy season and total, with the latter comprising the two formers. The diaspore removal rate, dispersal distance and diaspore destination experiments were performed for the plant species Miconia calvescens, Miconia prasina, Psychotria leiocarpa and Inga edulis. We recorded a large number of interactions, with diaspore cleaning being more frequent than removal. Ant-diaspore networks were nested, non-modular and little specialized. M. calvescens, M. prasina and I. edulis showed higher diaspore removal rates. Diaspore removal distances were the same among M. calvescens, M. prasina and I. edulis. In M. calvescens and I. edulis, the main diaspore destination was the ant’s nest. Our study shows that diaspore cleaning is the most common behavior in ant-diaspore interactions and there are no differences in the organization of interaction networks over the seasons. These results have implications for the future structure of plant communities, considering that a small part of the diaspores is removed, and that most of them are cleaned, favouring germination at the deposition site

Taquicardia ventricular: apresentação de linfoma com infiltração cardíaca

© 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España, S.L.U. All rights reserved.A 53-year-old man, with a 15-year history of mycosis fungoides (MF), presented with fever, dizziness, and presyncope. On examination, he was tachycardic (180 bpm) and hypotensive (100/70 mmHg). The ECG showed diffuse ST-segment depression, and cardiac troponin I was elevated (3.47 ng/ml). He was admitted with a suspected acute coronary syndrome. On the third day of hospitalization there were several episodes of sustained monomorphic ventricular tachycardia (MVT).info:eu-repo/semantics/publishedVersio

Atividade lítica de células natural "killer" durante a infecção pelo HIV-1 em indivíduos brasileiros

Natural killer cells are increasingly being considered an important component of innate resistance to viruses, but their role in HIV infection is controversial. Some investigators have found that natural killer cells do not confer a protective effect during the progression of HIV disease, whereas others have shown that natural killer cells may be protective and retard the progression of the disease, either through their lytic activity or by a chemokine-related suppression of HIV replication. In this study, we analyzed functional alterations in the activity of natural killer cells during HIV-1 infection using a natural killer cells activity assay with K562 cells as targets. RESULTS: Our results show that the activity of natural killer cells decreases only in the advanced phase of HIV infection and when high (40:1) effector cell-target cell ratios were used. The depression at this stage of the disease may be related to increased levels of some viral factors, such as gp120 or gag, that interfere with the binding capacity of natural killer cells, or to the decreased production of natural killer cells -activity-stimulating cytokines, such as IFN-a and IL-12, by monocytes, a subset of cells that are also affected in the late stage of HIV infection. The data suggest that decreased natural killer cells cell activity may contribute to the severe impairment of the immune system of patients in the late stages of HIV infection.As células "natural killer" são consideradas importante componente da resistência inata às viroses, mas seu papel na infecção pelo HIV é controverso. Alguns investigadores verificaram que as células "natural killer" não possuíam qualquer efeito protetor durante a progressão para doença, enquanto outros têm mostrado que as mesmas podem ser protetoras e retardar a progressão para doença, tanto devido à sua ação lítica como pela supressão por quimocinas. Em nosso estudo, analisamos as alterações funcionais na atividade durante infecção pelo HIV-1 usando ensaio com células K562 como alvo. Os resultados mostraram que a atividade "natural killer" está diminuída somente nas fases mais avançadas da doença e somente quando foi utilizar um número elevado de (40:1) células efetoras-alvos. A diminuição da atividade neste estágio da doença pode estar relacionada com a imunossupressão grave; a presença de alguns fatores virais, como a gp120 e gag, que interferem como a capacidade de ligação das células "natural killer"; ou a redução da produção de citocinas que estimulam a atividade "natural killer", como IFN-a e IL-12, por monócitos, uma subpopulação de células que são afetadas somente nos estágios mais avançados da infecção HIV. Assim, fica sugerido que a diminuição da atividade "natural killer" pode contribuir para alterações no sistema imune de pacientes nas fases avançadas da infecção HIV

Assessing the Long-Term Impact of Traditional Agriculture and the Mid-Term Impact of Intensification in Face of Local Climatic Changes

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Revamping de uma instalação de despoeiramento por via húmida de uma Refinaria de açúcar

O objetivo do estágio curricular foi o revamping da instalação de despoeiramento existente na Refinaria de açúcar da RAR, nomeadamente a representação da instalação, o cálculo da queda de pressão do caminho crítico, a sua ampliação e a minimização da deposição das poeiras ao longo da rede de transporte. Este trabalho foi realizado entre o dia 22 de fevereiro e o dia 17 de outubro de 2017 e incluiu o levantamento das dimensões e traçado da rede de transporte de poeira de açúcar e a contabilização de vários acessórios para posterior elaboração de um diagrama isométrico e plantas recorrendo ao software AutoCAD. Foram identificados ainda os cinco equipamentos processuais que podem ser acrescentados ao sistema existente. Inicialmente verificou-se que a origem da acumulação de açúcar tinha origem na alteração do caminho crítico devido a ampliações sucessivas da rede de transporte original, resultando numa distribuição irregular das velocidades de transporte. Em relação ao estado da rede de transporte, os diâmetros existentes não eram adequados para manter a velocidade de transporte desejada, as derivações deviam ser ligadas a 30º na conduta principal e acompanhadas de uma expansão do diâmetro da conduta, a maioria das curvas possuíam raios abruptos (equivalentes ao diâmetro da conduta), algumas válvulas encontravam-se danificadas, metade das ligações equipotenciais deveriam ser substituídas/instaladas e existiam captações sem pontos de medição ou bocais adequados. Todos estes fatores afetavam negativamente as velocidades de captação e transporte ao longo da rede. Foram então realizadas duas limpezas ao sistema (a primeira à conduta principal e a egunda às ramificações) de modo a poder verificar-se, recorrendo a um anemómetro, quais as velocidades de transporte nos ramais das captações e estimar o caudal global. O valor obtido não foi concordante com o caudal de operação indicado na curva caraterística do ventilador (40.000 m3 /h), após se quantificar a queda de pressão e a frequência de rotação do motor do ventilador. No entanto, nos dois conjuntos de medições de velocidade, o caudal global rondou os 10.000 m3 /h. Admitiu-se que esta discrepância poderia ser associada a fugas de ar, condutas colmatadas e ao nemómetro (alguns pontos de medição continham poeiras que ficaram presas à turbina). Foram ainda realizados ensaios às correntes de água doce na etapa de recuperação de odo a avaliar o caudal de poeiras aspiradas. No entanto, não foi possível fechar o balanço de massa, o que poderá indicar uma de duas hipóteses: ou a corrente overflow stá a sobressaturar a solução contida no tanque de lavagem ou o caudal de ar considerado (40.000 m3 /h) é muito superior ao real. Partindo da base de cálculo, em que a velocidade de transporte de cada ramal e na linha principal deve ser 22 m/s, foram calculadas todas as velocidades ao longo da rede de transporte. Comparadas as perdas de carga de todos os percursos captação atmosfera, determinou-se que o ponto crítico se situa na captação LS10A1, no topo do silo de 40 toneladas. A queda de pressão do caminho crítico situa-se entre os 4.300 e os 5.000 Pa. Numa etapa seguinte, colaborou-se com uma empresa de despoeiramento (Vento Domável) para efetuar o recálculo dos diâmetros das condutas e elaboraram-se novos cenários considerando a ampliação do sistema em cinco novas captações e respetivos ramais. Depois de selecionado o cenário a desenvolver, foram idealizadas 19 alterações de traçado que beneficiarão a performance do sistema, dimensionaram-se as captações e as condutas da rede de transporte pelo método de igual queda de pressão e determinou-se a capacidade necessária para o ventilador (48.000 m3 /h e 4.500 Pa) e para a câmara de lavagem. A empresa contratada formulou um caderno de encargos em que considerou a substituição integral da rede de transporte e dos equipamentos, assim como a implementação das novas linhas. A velocidade de transporte do projeto foi alterada de 22 para 25 m/s para garantir uma aspiração eficaz dentro da gama de velocidades recomendada. Com base nas especificações definidas no caderno de encargos foi possível estimar os custos dos materiais para a substituição da rede de transporte em 45.675 € (considerando apenas os troços retos das condutas, reduções concêntricas para as captações, curvas, derivações e pares flangeados). Estes custos foram fragmentados e recalculados para os cenários de substituição parcial e para a implementação das novas captações. Por fim, foi possível estimar uma poupança de 19.961 €, mantendo e aproveitando as condutas cujos diâmetros são adequados. Depois de obtido o caderno de encargos realizou-se um pedido de orçamentação a várias empresas para a substituição integral do sistema. As empresas a concurso foram a Vento Domável, Planiclima e a Despoiravent e estas propuseram um investimento de, respetivamente, 297.749, 165.070 e 252.400 €. A proposta da Planiclima foi a mais baixa pois não considerou o fornecimento de equipamentos para a etapa de recuperação. Como os montantes propostos ultrapassaram a verba disponível decidiu-se implementar apenas as novas captações. Repetiu-se, então, o pedido de orçamento e reuniram-se as propostas formalizadas. As empresas a concurso foram a SITAPE, a Vento Domável, a Planiclima, a Despoiravent e a Retaflex e propuseram, respetivamente, um investimento de 10.927, 10.558, 13.049, 10.300 e 4.500 €. A proposta da Retaflex foi a mais barata visto que o material considerado para a rede de transporte é, sensivelmente, três vezes mais barato que o material especificado no caderno de encargos. Elegeu-se então a Despoiravent para ser a empresa responsável pela intervenção, visto que praticaram o preço mais baixo e respeitaram na íntegra as especificações do caderno de encargos.The internship took place at RAR Açúcar, between february 22nd and october 17th 2017. The curricular internship’s goal is the revamping of the Refinery’s dedusting unit, namely, the construction of the system’s schematic representation, the calculation of the critical path’s pressure drop, the minimization of powder settling along the piping network and the extension of the system’s capacity. After an exhaustive data collection of the piping network’s dimensions and layout, as well as the listing of the various pipe fittings, an isometric diagram and plan view were obtained by using the AutoCAD software. Five process equipments that could be added to the dedusting system were identified. The origin of the powder’s build-up is based on the fact that several extensions to the original piping network have changed the critical path, yielding an irregular air velocity distribution along the transport network. The network’s current pipe diameters aren’t appropriate for keeping the desired transport velocity along the network; all of the branch lines should be connected at an angle of 30° (with respect to the direction of the flow in the main pipe) and followed by an adequate expansion of the main pipe’s diameter; most elbows have sudden radii of curvature (matching the pipe’s diameter); some valves are damaged; half of the equipotential connections should be replaced and there are powder capture points without a suitable opening or an air velocity measuring point. All these factors harm the capture/transport velocity distributions along the pipeline. In order to predict the system’s total airflow, it was necessary to measure the velocities at each branch line with an anemometer. The system’s pipelines were cleansed twice (once for the main piping and at another occasion for the branch lines). After quantifying the ventilator’s pressure drop and its engine rotation rate, it is possible to read on the equipment’s characteristic curve the expected airflow, which is roughly four times larger than the combined airflow of all the branch lines. However, the source of this discrepancy is, at a smaller scale, due to air leakage and also due to piping blockage by the built-up powder. The discrepancy could be minimized if the entire system cleansing took place in only one intervention. An anemometer isn’t the most suitable measuring device since some of the measuring points are located in areas with permanent powder dispersion and prolonged exposure to these kinds of environments may clog the propeller’s blades. The sweet water streams of the powder recovery stage were assessed in order to determine the mass flow of the exhausted powders, by a mass balance applied to the recovery stage. Although the balance was not validated two conclusions were drawn. Either the considered system airflow (40.000 m3 /h) is too high or the overflow stream is supersaturating the sweet water solution contained in the system’s washing tank. Assuming a transport air velocity of 22 m/s at each branch line as a calculation basis it was possible to determine all the velocities and airflows along the piping network. This was achieved after dividing the streams in the same manner as in the convergence diagram. Afterwards, the pressure drop was calculated in each one of the system’s air streams. By comparing the pressure drop of each capture point to atmosphere route, it was determined that the critical point stands on top of the 40 ton silo (capture point LS10A1). Based on the methods used the predicted pressure drop of the critical path stands between 4.300 and 5.000 Pa. Various friction factors were calculated based on empirical equations, the Moody Chart and a friction chart. Within the pipe fittings, two methods were compared for the determination of the local pressure loss factor k for both inlet streams of the branch connections. Then followed the collaboration with a company specialized in Ventilation Engineering to redesign the piping network’s diameters and adjust to new scenarios considering the system’s extension of five new capture points and branch lines. During the development of the selected scenario, 19 piping layout changings that are beneficial to the system were conceived, the capture points and the piping network’s ducts were sized using the equal pressure drop method and the ventilation needs were determined (48.000 m3 /h e 4500 Pa). The company formalized the descriptive memory and specifications manual for the assignment, considering the full replacement of the dedusting unit’s equipment and the transport network’s ducts, all the while adding the new capture points and branch lines. The transport velocity was raised from 22 to 25 m/s by the company to guarantee an effective aspiration within the recommended velocity gage of 20 to 25 m/s. Based on the specifications found on the descriptive memory it was possible to assess the cost of the materials for the full replacement of the ducts at 45.675 € (considering straight ducts, concentric reductions for the capture points, elbows, branch connections and flanged pairs). These costs were distinguished based on the type of material and the data was ajusted considering two scenarios: a partial replacement of the pipelines and the setup of the new capture points. The results show that it would be possible to save 19.961 € (out of 45.675 €), by keeping the branch lines which diameters are suitable. After obtaining the descriptive memory of the project a budget request was made to several companies, considering the full substitution of the system. The companies were Vento Domável, Planiclima and Despoiravent and the investment they proposed rose to 297.749 €, 165.070 € and 252.400 €. Planiclima’s proposal is significantly lower since they did not consider the supply of adequate equipments for the powder recovery stage. Since the available funds required for the intervention are insufficient it was decided to install only the new capture points. The budget requests were repeated. The contestants were SITAPE, Vento Domável, Planiclima, Despoiravent and Retaflex and the amounts they asked for the intervention were, respectively, 10.927 €, 10.558 €, 13.049 €, 10.300 € and 4.500 €. Retaflex’s offer is significantly lower than the other ones since the material considered for the pipelines is around three times cheaper than the material specified on the descriptive memory. Despoiravent was selected to develop the intervention since they practiced the lowest price while fully respecting the descriptive memory’s specifications