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- Does the financial system support economic growth in times of financialisation? Evidence for PortugalPublication . Barradas, RicardoThe purpose of this paper is the conduction of a time series econometric analysis in order to examine empirically the relationship between the financial system and economic growth in Portugal from 1977 to 2016. The Portuguese financial system has experienced a strong wave of privatisations, liberalisations and deregulations since the adhesion of Portugal to the European Economic Community in 1986, which has not favoured a sustained path of strong economic growth since then. The growth of the financial system played even a crucial role in the recent sovereign debt crisis in Portugal, casting doubts on the conventional hypothesis on the finance- growth nexus. The paper estimates a linear growth model and a non-linear growth model, which includes four proxies for the financial system (money supply, credit, financial value added and stock market capitalisation) and four further control variables (inflation, government consumption, trade openness and education). The paper finds a negative linear relationship between the banking system and Portuguese economic growth, a positive linear relationship between the stock markets and Portuguese economic growth, a concave quadratic relationship between the banking system and Portuguese economic growth, and a convex quadratic relationship between the stock markets and Portuguese economic growth. This suggests that Portuguese policy makers should canalise efforts to decrease the importance of banking system and to increase the importance of stock markets in order to support more robust economic growth in the coming years.
- Effect of mesenchymal stem cell source on the molecular profile of extracellular vesicles for cell therapyPublication . Pires, Filipa Adriana Rego; Platzgummer, Ana Margarida; Calado, CecíliaABSTRACT - Mesenchymal stem cells (MSCs) obtained from different sources have been considered for cell therapeutics against several diseases, where its derived extracellular vesicles (EVs) are the primary mediators of the cells paracrine effect. The present work aimed to evaluate the influence of different MSC sources, as adipose tissue, bone marrow and umbilical cord matrix on the molecular profile of EVs acquired by Fourier-Transform Infrared (FTIR) Spectroscopy after spectra pre-processing and its principal component and hierarchical cluster analysis. It was evaluated the EVs, MSCs, and conditioned media molecular profiles in the function of MSC source, MSC donor (i.e. 3 donors per source), and media composition (xenogeneic-free (XF) vs serum-containing medium (DMEM-FBS)). Two replicates cultures per donor were considered. EVs were obtained from the MSC conditioned media based on a kit assay using a polymer that, however, absorbs on the EVs surface leading to interference on the EVs spectra signal. The EVs' high dilution factor leads to the polymer partial desorption, as observed by other authors. Due to the variability of the desorption process, lower reproducible spectra from EVs were obtained. Despite that, it was possible to observe that EVs' molecular profile depended on the media type and, for each MSC source, on the MSC donor. It was also observed that EVs' molecular profile obtained from DMEM cultures apparently presented a more homogenous chemical profile than EVs obtained with XF medium. Diverse ratios between infrared spectral bands were identified, that discriminate at a 5% significance, in meaningful terms, the EVs molecular profile in the function of the culture medium composition. The MSC spectra were also highly variable due to different growth patterns. Even so, it was possible to observe that MSC molecular profile depended on the culture media type, being observed a more homogeneous molecular profile when cells were cultured in XF than in DMEM medium. When grown on DMEM medium, it was possible to observe that MSC molecular profile depended on the MSC source. MSC molecular profile also apparently depended on the MSC donor. A very similar conditioned media spectra were obtained from the different cultures and, consequently, higher reproducible molecular profiles were obtained in relation to MSC and EVs analyses. It was observed that conditioned media molecular profile depended on MSC source, MSC donor, and culture media composition. A lower variable molecular profile was observed when using XF medium, as observed with MSC molecular profile. From the EVs, MSC, and conditioned media molecular profiles, the best reproductive results were obtained from the conditioned media, which pointed that it was affected by the MSC donor and source. The impact of the culture media type, MSC source, and donor was also partially observed on the EVs and MSC molecular profile. All these results point to the impact of the culture media, MSC source, and donor on the EVs molecular profile. Therefore, in therapies-cell-based and based EVs-based, the impact of culture media, MSC source, and the donor should be considered.
- Pseudocapacitive behaviour of FeSx grown on stainless steel up to 1.8 V in aqueous electrolytePublication . Upadhyay, Kush; Tuyen, Nguyen; Moura E Silva, Teresa; Carmezim, Maria; MONTEMOR, MARIAIron sulfide was synthesized for 4 h, 7 h and 12 h by a hydrothermal process directly on stainless steel current collectors. The synthesis time determined the material morphology and electrochemical response. The shortest synthesis time promoted the formation of randomly oriented nanowires that evolved to nanosheets decorated with nanoflakes, organized in a cuboidal-like morphology upon longer synthesis times. XRD, Raman, FTIR and XPS investigations confirmed the formation of FeSx. The electrochemical activity was studied in a potential window ranging from - 0.95 to 0 V and the material obtained after 7 h of synthesis stored the maximum specific capacitance of 730 mF cm(-2) at the current density of 1 mA cm(-2). This material also retained approximately 34% of its initial capacitance at 10 mA cm(-2) and showed very good cycling stability, keeping around 95% of the specific capacitance after 2000 galvanostatic charge-discharge (GCD) cycles. The kinetic analysis of the electrochemical results revealed the predominance of diffusional controlled processes. An asymmetric cell was assembled using FeS,, as negative electrode and carbon nanofoam (CNF) as positive electrode. The FeSx parallel to CNF cell showed enhanced capacitive response in a potential window of 1.8 V in 1 M Na2SO4 electrolyte and delivered specific capacitance of 236 mF cm(-2) at 0.5 mA cm(-2) with good rate capability. The FeSx parallel to CNF cell stored maximum energy density of 0.11 mW h cm(-2) at the power density of 0.45 mW cm(-2). The cell showed very good stability by retaining 83% of the initial capacitance after 2000 cycles of consecutive charge discharge.
- Inertial-sensor based 3D kinematics in the differential diagnosis between Parkinson's disease and atypical parkinsonismPublication . Ferreira, Pedro Correia; Mendonça, Marcelo; Jorge, Pedro MendesABSTRACT - Background, and Objectives: Parkinson’s disease (PD) is the most frequent disorder presenting with Parkinsonism. However, atypical parkinsonian disorders (such as Progressive Supranuclear Palsy (PSP) and Multiple System Atrophy (MSA)) share some clinical features of PD but have different prognoses and are therefore important to distinguish from PD. The development of new and cost-effective tools to help clinicians in differential diagnosis is therefore paramount. In this work, we perform sensor-based kinematic analysis to find significant differences between PD and atypical parkinsonism, while developing an experimental machine learning model with clinical applicability. Subjects and Methods: 32 subjects with PD (mean age 69.7 ± 11.3, 14 male 17 female), 11 with atypical parkinsonism (9 PSP, 1 MSA, 1 vascular parkinsonism, mean age 72.9 ± 6.1, 8 male 3 female) and 33 age-gender matched controls (mean age 68.0 ± 12.6, 14 male 19 female) were recruited from the outpatient clinic in routine appointments at Hospital Egas Moniz, Lisboa. Using a set of 7 inertial sensors, leveraged by biomechanical models, we collected data from gait and posture during a 3x20m walk and stance. Moreover, using one inertial sensor, we recorded finger tapping tests. We conducted the analysis in two different ways: controls vs parkinsonian group (ill – PD + atypical), and within the parkinsonian group i.e. PD vs atypical. Results: Compared to controls, parkinsonian subjects displayed lower cadence (controls 109.420 ± 12.519 steps/min, ill 100.566 ± 13.432 steps/min, p = 0.006), step length (controls 0.512 ± 0.086 m, ill 0.442 ± 0.100 m, p = 0.003) and speed (controls 0.996 ± 0.190 m/s, ill 0.773 ± 0.202 m/s, p < 0.001). Double support was increased in the parkinsonian cohort (controls 36.355 ± 3.253 %, ill 39.827 ± 5.685 %, p = 0.003), and angular variables were decreased for the most part (i.e. hip flexion mean velocity controls 67.900 ± 14.974 cm/s, ill 55.180 ± 12.814 cm/s, p<0.001). A 10-fold cross-validation random forest model classified controls vs parkinsonian subjects with an accuracy of 82.9%. PD and atypical cohorts also differed significantly, with the latter displaying high asymmetry in many angular parameters: knee mean velocity asymmetry (PD 0.919 ± 0.710 cm/s, atypical 3.392 ± 3.836 cm/s, p = 0.001), hip adduction mean velocity asymmetry (PD 0.268 ± 0.177 cm/s, atypical 0.656 ± 0.563 cm/s, p = 0.002) and ankle mean velocity asymmetry (PD 0.636 ± 0.537 cm/s, atypical 1.586 ± 1.227 cm/s, p = 0.002). The same machine learning model classified the PD vs atypical cohorts with 76.3% accuracy. Ongoing work is being developed in the analysis of finger tapping and postural metrics that can improve the discrimination models. Conclusions: The main objectives of this work were achieved. We hypothesize that atypical parkinsonian subjects develop an instable gait where asymmetry is highly pronounced compared to PD. Furthermore, we believe inertial sensor technology supported by machine learning should become a regularly applied technique in the differential diagnosis of these syndromes.
- Os benefícios fiscais no contexto da reabilitação urbanaPublication . Palminha, Alexandra Patrício; Costa, Paulo Nogueira daNo âmbito da legislação fiscal portuguesa, os benefícios fiscais no contexto da reabilitação urbana, apesar de não serem uma novidade, têm assumido um papel bastante relevante neste setor, sobretudo nos últimos anos. A temática da reabilitação urbana tem, portanto, sofrido uma evolução ao longo dos tempos de modo a dar resposta às novas realidades que se fazem sentir, mormente de ordem social, ambiental, económica e cultural. Como forma de impulsionar este fenómeno evolutivo, é primordial que se criem mecanismos e procedimentos aptos a dinamizar e promover a reabilitação urbana, pelo que, a atividade de reabilitação urbana, atualmente, tem como suporte um regime de tributação atrativo, o qual constitui o objeto da presente dissertação. É neste sentido que surge a necessidade de aprofundar o conhecimento ao nível dos vários benefícios e incentivos que a fiscalidade apresenta, quer ao nível dos impostos sobre o património, sobre o rendimento e sobre o consumo e, ainda, analisar questões jurisprudenciais relevantes.
- O sobre-endividamento das famílias portuguesas e a penhora da casa de morada da famíliaPublication . Henriques, Daniela Ribeiro; Martins, Jesuíno AlcântaraPortugal atravessou uma grave crise económica e financeira nos últimos anos, cujos efeitos ainda se fazem sentir. Esta, foi resultado de inúmeros fatores, nomeadamente, da criação diversas políticas públicas de incentivo à aquisição de habitação própria, a facilidade na concessão de crédito, bem como a diminuição da taxa de poupança das famílias. Todos estes fatores conduziram a que várias famílias se encontrassem impossibilitadas de fazer face às suas dívidas, encontrando-se em situações de sobre-endividamento. Consequentemente, foram instaurados processos com força executória, com o intuito do credor ver satisfeito o seu crédito. Por sua vez, penhorados os imóveis, afetos à habitação própria e permanente do executado e/ou do respetivo agregado familiar, foram várias as famílias que se viram obrigadas a deixar a sua própria casa, sendo despejadas, uma vez promovida a venda do respetivo bem. Desta forma e, no que concerne à penhorabilidade da casa de morada de família, é necessário abordar temáticas como, o princípio da dignidade humana, sendo este um valor intrínseco ao ser humano, aquando o seu nascimento e, o direito à habitação, uma vez que todas as pessoas necessitam de um local apropriado para a sua privacidade, comodidade e construção de família. Por último e, não menos relevante, a introdução da Lei n.o 13/2016, de 23 de maio, tendo em consideração os impedimentos legais à realização da venda, no âmbito dos processos de execução fiscal, bem como fazer menção à criação das políticas destinas à proteção da casa de morada de família.
- The contemporary jazz composer: the importance of the conception of the source material in the compositional processPublication . Subatin, Javier; Pinheiro, RicardoABSTRACT - This study is focused on the compositional process of current jazz composers, more specifically on the starting idea and the conception of the basic material for a new composition, or as Ed Neumeister named it when describing his compositional process, “the source material”. The aim of the exploratory study is to attempt to find an initial approach to a comprehensive way of understanding how jazz composers deal with the creative process in the first stage of composition. For this purpose, a qualitative research was performed interviewing 6 Portuguese jazz composers with a distinguished career. Taking the above into account, the ultimate objective of this project was to try to develop a variety of compositional methods that can help dealing with the creative aspects of the starting point of a new composition. The results allowed to design a map that can be applied as a composers’ guideline to approach the compositional process, at the same time as for the analysis of the creative process of the first stage of composing music. Finally, the above-mentioned map was used to analyze one original piece regarding the compositional process during the conception of the source material.
- Biomarkers research for diagnosis and prognosis of rejections of renal allograft in human transplant by fourier transform infrared spectroscopyPublication . Ramalhete, Luís Manuel Pires; Calado, CecíliaABSTRACT - Background and main goals: Renal transplantation, when possible, is the treatment of choice for end-stage kidney disease as it enables a much higher quality of life than dialysis. However, one of its major problems is allograft rejection. The present project aims to promote serum biomarkers discovery for diagnosis and prognosis of the rejection processes of allograft organs and to evaluate the efficiency of organ rescue therapies, in a rapid, economic but also sensitive and specific mode. It was aimed to develop a new biomarker discovery methodology based on Fourier Transformed Infrared (FTIR) spectroscopy associated with multivariate data analysis and machine learning techniques. Methods: A total of 38 healthy non-transplanted participants, 59 transplanted patients with kidney allograft, from which 12 also received an allograft pancreas or liver, were considered. From the transplanted patients, 29 presented rejection processes. The FTIR spectra were acquired from serum samples of non-transplanted (n=38) and transplanted without (n=213) and with rejection (n=360) processes. It was optimized the dilution degree of the serum samples before spectra acquisition and the spectra pre-processing methods. Diverse spectra unsupervised and supervised processing multivariate data analysis were implemented to search for patterns in data and to develop classification methods to predict the diagnosis, prognosis, and immune mechanisms of rejection and the efficiency of the organ rescue treatment. It was also developed an in vitro method based on T-lymphocyte spectra to detect T-cells activation. This assay was based on whole blood samples of 8 healthy non-transplanted volunteers. Results: It was possible to develop good classification models to predict which patients will develop a rejection process, as for example by Random Forest an AUC of 0.94 was obtained. It was also possible to develop good models to predict the risk of the rejection process, as early as 120 days before it was detected in biopsies. For example, by Support Vector Machine an AUC of 0.804, and a sensitivity and specificity of 71.90% and 86.05 % were obtained, respectively. In other models, even before transplanting, it was also possible to predict the risk of rejection, e.g. with a Neural Network model sensitivity and specificity of 93.33% and 96.55 % were achieved, respectively. In a small cohort of patients (n=20) with rejection processes, and under immunotherapy to minimize the organ loss, it was possible to predict the efficiency of the organ rescue treatment, with e.g. Naïve Bayes or Neural Network models obtaining an AUC of 1.0 with a classification accuracy of 0.95 and 0.90 respectively. Considering the serum analysis at the time of biopsy-proven cellular (n=12) and humoral (n=42) rejection, it was not possible to develop a good prediction model, probably due to a high mix of immune rejection mechanisms. However, it was possible to identify ratios of spectral peaks based on the 2nd derivative spectra that discriminate humoral from cellular rejection (p<0.05). It was also developed an in vitro rapid test (1hr) to detect T-lymphocyte activation from the T-cells spectra that enabled the 100% discrimination, by Hierarchical Cluster Analysis of second derivative spectra, the resting T-cells from activated T-cells. Conclusions: FTIR spectroscopy of serum coupled with unsupervised and supervised processing multivariate data analysis enabled to development of good predictive models of the rejection diagnosis and prognosis, the risk of rejection before transplantation, and the efficiency of the organ rescue treatments. The basis of an in vitro method to predict T-lymphocyte activation was also developed, which could enable in the future the rapid prediction of cellular rejection processes. All these new methods, due to simplicity, speed, and economics, could increase the monitoring of these types of patients, identify critical patients with an increased risk of rejection processes, and eventually promoting the adjustment of immunotherapies for organ rescue. These could lead to disrupting modes of management of these types of patients towards a significant increase of quality of life and even of life expectancy, and in a highly economic mode.
- Conhecimentos sobre contagem de hidratos de carbono e controlo metabólico de utentes com sistema de perfusão subcutânea contínua de insulinaPublication . Lopes, Cristiana; Almeida, Anabela; Carolino, Elisabete; Matos, Ana Catarina; Luiz, Henrique Vara; Raimundo, Luísa; Portugal, JorgeA prevalência da Diabetes Mellitus tipo 1 tem vindo a aumentar nos últimos anos. O tratamento intensivo através de Sistema de Perfusão Subcutânea Contínua de Insulina é o método mais fisiológico de administração de insulina atualmente disponível. Para que este seja eficaz é fundamental ter conhecimentos sobre a composição dos alimentos, particularmente os Hidratos de Carbono. O presente estudo teve como objetivos avaliar e caracterizar o controlo metabólico, compará-lo antes e depois do Sistema de Perfusão Subcutânea Contínua de Insulina, avaliar os conhecimentos de contagem de Hidratos de Carbono e relacioná-los com o controlo metabólico. Trata-se de um estudo observacional, analítico e retrospetivo, com uma amostra de conveniência constituída pelos utentes com consulta entre novembro 2017 e março de 2018 no Hospital Garcia de Orta. A avaliação do controlo metabólico foi realizada através da HbA1c. Na avaliação dos conhecimentos sobre contagem de Hidratos de Carbono utilizou-se uma adaptação do questionário PedCarbQuiz. Avaliaram-se 60 indivíduos com uma média de idades 21,3 ± 14,27 anos [2 - 57]. Aquando a colocação do Sistema de Perfusão Subcutânea Contínua de Insulina, apenas 23,6% da amostra se encontrava com a HbA1c dentro dos valores recomendados. Três meses após a colocação do Sistema de Perfusão Subcutânea Contínua de Insulina verificou-se uma diminuição significativa da HbA1c, que estabilizou após os 6 primeiros meses. Relativamente aos conhecimentos sobre contagem de HC, 78,3% possuíam nível muito bom e os restantes nível bom. Não foi detetada correlação significativa entre a HbA1c e os conhecimentos de contagem de Hidratos de Carbono, ou seja, ter mais conhecimentos não demonstrou ter influência no controlo metabólico da amostra.
- A importância da educação fiscal na sociedade portuguesaPublication . Bogalho, Joana; Palma, Clotilde CeloricoO trabalho apresentado aborda a necessidade do Estado em garantir maior equidade na redistribuição de rendimentos existentes na Sociedade. Essa redistribuição acontece essencialmente através da cobrança de impostos aos contribuintes. Deste modo, é fulcral a reafectação dos recursos dos contribuintes através da Política Fiscal definida pelo Estado. Os impostos cumprem uma função importante na sociedade, visto que, com os recursos arrecadados via tributação, o Estado consegue financiar-se e promover bens públicos à população e colmatar as diferenças existentes face aos diferentes níveis de rendimentos. Contudo, para uma maior aceitação das medidas e instrumentos fiscais por parte dos cidadãos, cabe ao Estado disponibilizar ferramentas para instruir os mesmos da necessidade e pertinência da Política Fiscal, permitindo a consciência quanto à necessidade de financiamento do Estado através da captação de impostos e do seu dever de participar na aplicação, arrecadação e fiscalização da receita pública. Neste sentido, o Orçamento do Estado, o Orçamento Participativo e a Educação Fiscal são exemplos de métodos adotados para transmitir aos cidadãos atitudes sociais e morais favoráveis à responsabilidade fiscal e contrárias às condutas fraudulentas. Os cidadãos através de iniciativas como o Orçamento Participativo tem a possibilidade de um maior protagonismo na alocação dos recursos financeiros do Estado. Contudo, o Estado é lesado por alguns comportamentos ilícitos provenientes dos contribuintes com o objetivo de evitar a recolha de impostos, denominam-se por Elisão e Evasão Fiscal. Como consequência desses comportamentos, em 2016, o Estado Português viu-se privado de arrecadar nos seus cofres 1 755 milhões de euros em impostos. Por fim, o objeto da investigação apresentada é a importância da Educação Fiscal na sociedade portuguesa. Os inquiridos evidenciam desconhecimento sobre a existência de programas de Educação Fiscal e a necessidade do contacto com áreas financeiras durante o percurso académico. No entanto, afirmam compreender a importância das suas obrigações fiscais e que cumprem os seus deveres fiscais de forma autónoma. Contudo, é ainda assinalado pelos inquiridos que o destino das suas contribuições fiscais é uma incógnita, não sabendo ou não demonstrando interesse sobre a temática.