6,133 research outputs found
A Panel ARDL Approach
Gross Domestic Product (GDP) has been the most widely accepted measure of economic performance, but it fails to accurately measure economic development, overlooking key aspects of quality of life and sustainability. Over the last few years, concern about the future of our planet and sustainability of human activity rose among public eye and political institutions, due to the increased natural resources exploitation, and the intensification and deepening of globalization. Thereby, the Index of Sustainable Economic Welfare (ISEW) emerges as the dominant alternative. This paper aims to: (i) compare both GDP and ISEW as measures of economic performance; and (ii) establish the effects of natural resources exploitation, and globalization on both economic growth and sustainable development. The research question is: Are globalization and natural resources exploitation harmful to economic development? Diagnostic tests show presence of cross-section dependence, heteroskedasticity and serial correlation. Thus, Driscoll-Kraay estimator is performed due to its robustness in the presence of these phenomena. A Panel Autoregressive Distributed Lag approach is used, which allows to check for short and long-term effects of the variables. The panel is composed by 14 OECD countries, and uses annual data for the time span from 1995 to 2013. Results show that natural resource rents have a positive effect on GDP per capita in the short-run and a negative effect on ISEW per capita both on short- and long-run. These results reveal that enhancing GDP does not account for the impacts of changes in natural capital and that natural resource exploitation may represent a hazard to sustainable development. Trade openness has a positive impact on short-term economic growth and a negative impact on long-term sustainable development. Other results show that social globalization has a positive impact on long-term economic growth and that political integration is positive for economic welfare. Policy makers ought to consider ISEW as an alternative and more accurate measure of economic development, should implement policies that reduce the depletion of natural resources, and confine the harmful effects of globalization to enhance economic development and create more welfare.O Produto Interno Bruto (PIB) tem sido a medida mais aceite de desempenho económico, apesar de não medir com exatidão o desenvolvimento económico, ignorando aspetos-chave da qualidade de vida e sustentabilidade. Ao longo dos últimos anos, a preocupação com o futuro do nosso planeta e a sustentabilidade da atividade humana tem-se tornado foco das instituições públicas e políticas, devido à crescente exploração dos recursos naturais e à intensificação e aprofundamento da globalização. Deste modo, o Índice de Bem-estar Económico Sustentável (ISEW) surge como a alternativa dominante. Este artigo procura: (i) comparar o PIB e o ISEW enquanto medidas de performance económica; e (ii) identificar os efeitos resultantes da exploração de recursos naturais e do fenómeno da globalização tanto no crescimento económico como no desenvolvimento sustentável. A questão de investigação é: serão a globalização e a exploração dos recursos naturais prejudiciais ao desenvolvimento económico? Testes de diagnóstico revelam a presença de cross-sectional dependence entre as variáveis, heterocedasticidade e auto-correlação. Assim, o estimador Driscoll-Kraay é utilizado devido à sua robustez na presença destes fenómenos. A abordagem Panel Autoregressive Distributed Lag é utilizada, permitindo assim verificar os efeitos de curto e longo prazo. O painel é composto por 14 países desenvolvidos, membros da OCDE, e são utilizados dados anuais para o horizonte temporal compreendido entre 1995 e 2013. Os resultados obtidos mostram que as receitas provenientes dos recursos naturais têm um efeito positivo no PIB per capita no curto prazo, enquanto que no ISEW se verifica um efeito negativo tanto no curto como a longo prazo. Estes resultados demonstram que o aumento do PIB não tem em conta os impactos das mudanças no capital natural e que a exploração de recursos naturais pode constituir um entrave ao desenvolvimento sustentável. A abertura comercial tem um impacto positivo para o crescimento económico no curto prazo e um impacto negativo no desenvolvimento sustentável de longo prazo. Outros resultados revelam que a globalização social tem um impacto positivo no crescimento económico a longo prazo e que a integração política é positiva para o bem-estar económico. Os formuladores de políticas devem considerar o ISEW como uma medida alternativa e mais precisa do desenvolvimento económico, devendo implementar políticas que reduzam o desgaste dos recursos naturais, e limitar os efeitos nocivos da globalização para melhorar o desenvolvimento económico e criar mais bem-estar para as populações
Manual asymmetries in bimanual isochronous tapping tasks in children
Mestrado em Desenvolvimento da Criança na Variante de Desenvolvimento MotorThe reasons why some people use preferably one hand to perform everyday tasks instead of the other are still the object of study of
many investigators. Even if ambidexterity would seem an advantage,
the fact is, even small babies show preferences for one side over the other on their most basic movements. These lateral asymmetries are always present but suffer fluctuations throughout life and even from
one activity to another, performed minutes later.
A very common and effective way of studying manual asymmetries is through tapping tasks, following and adapting the models of
authors like Stevens (1886) and Wing and Kristofferson (1973).
These authors showed the scientific community that the synchronization-continuation experiments were valid and could be used to investigate the process of timekeeping and a variety of different aspects related to motor control. Our work was based on these previous investigations and has the
purpose of analyzing the ability of keeping a rhythm, in children on a bimanual tapping task, as well as the manual asymmetries
displayed while doing so. The children's performance was compared to that of adult musicians, who are expected to have a better than average performance on this type of tasks
Dynamic Consumption and Portfolio Choice with Ambiguity about Stochastic Volatility
We introduce ambiguity about the variance of the risky asset's return in the model of Chacko and Viceira (2005) for dynamic consumption and portfolio choice with stochastic variance. We find that, with investors being able to update their portfolio continuously (as a function of the instantaneous variance), ambiguity has no impact. To shed some light on the case in which continuous portfolio updating is not possible, we also evaluate the effect of ambiguity when investors must use their expectation of future variance for their portfolio decision. In the latter scenario, demand for the risky asset can be decomposed into three components: myopic and intertemporal hedging demands (as in Chacko and Viceira (2005)) and ambiguity demand. Using long-run US data, Chacko and Viceira (2005) found that intertemporal hedging demand is empirically small, suggesting a low impact of stochastic variance on portfolio choice. Using the same calibration, we find that ambiguity demand may be very high, much more than intertemporal hedging demand. Therefore, stochastic variance can be very relevant for portfolio choice, not because of the variance risk, but because of investors' ambiguity about variance.Asset Allocation, Stochastic Volatility, Ambiguity
An analysis of the implementation of problem-based learning at the Department of Energy Technology – Aalborg University
Towards a quantitative alloy
Dissertação de mestrado integrado em Engenharia InformáticaWhen one comes across a new problem that needs to be solved, by abstracting from its associated details
in a simple and concise way through the use of formal methods, one is able to better understand the matter
at hand. Alloy (Jackson, 2012), a declarative specification language based on relational logic, is an example
of an effective modelling tool, allowing high-level specification of potentially very complex systems. However,
along with the irrelevant information, measurable data of the system is often lost in the abstraction as well,
making it not as adequate for certain situations.
The Alloy Analyzer represents the relations under analysis by Boolean matrices. By extending this type of
structure to:
• numeric matrices, over N0
, one is able to work with multirelations, i.e. relations whose arcs are
weighted; each tuple is thus associated with a natural number, which allows reasoning in a similar
fashion as in optimization problems and integer programming techniques;
• left-Stochastic matrices, one is able to model faulty behaviour and other forms of quantitative
information about software systems in a probabilistic way; in particular, this introduces the notion of
a probabilistic contract in software design.
Such an increase in Alloy’s capabilities strengthens its position in the area of formal methods for software
design, in particular towards becoming a quantitative formal method.
This dissertation explores the motivation and importance behind quantitative analysis by studying and
establishing theoretical foundations through categorial approaches to accomplish such reasoning in Alloy.
This starts by reviewing the required tools to support such groundwork and proceeds to the design and
implementation of such a quantitative Alloy extension.
This project aims to promote the evolution of quantitative formal methods by successfully achieving
quantitative abstractions in Alloy, extending its support to these concepts and implementing them in the
Alloy Analyzer.Quando se depara com um novo problema que precisa de ser resolvido, ao abstrair dos seus detalhes
associados de forma simples e concisa recorrendo a métodos formais, é possível compreender melhor
o assunto em questão. Alloy (Jackson, 2012), uma linguagem de especificação declarativa baseada em
lógica relacional, é um exemplo de uma ferramenta de modelação eficaz, possibilitando especificações
de alto-nível de sistemas potencialmente bastante complexos. Contudo, em conjunto com a informação
irrelevante, os dados mensuráveis são muitas vezes também perdidos na abstração, tornando-a não tão
adequada para certas situações.
O Alloy Analyzer representa as relações sujeitas a análise através de matrizes Booleanas. Ao estender
este tipo de estrutura para:
• matrizes numéricas, em N0
, é possível lidar com multirelações, i.e., relações cujos arcos são
pesados; cada tuplo é consequentemente associado a um número natural, o que proporciona uma
linha de raciocínio semelhante à de técnicas de problemas de otimização e de programação inteira;
• matrizes estocásticas, permitindo a modelação de comportamento defeituoso e de outros tipos de
informação quantitativa de sistemas de software probabilisticamente; em particular, é introduzida a
noção de contrato probabilístico em design de software.
Tal aumento às capacidades do Alloy, fortalece a sua posição na área de métodos formais para design de
software, em particular, a caminho de se tornar um método formal quantitativo.
Esta dissertação explora a motivação e a importância subjacente à análise quantitativa, a partir do estudo
e consolidação dos fundamentos teóricos através de abordagens categóricas de forma a conseguir suportar
esse tipo de raciocínio em Alloy. Inicialmente, as ferramentas imprescindíveis para assegurar tal base são
analisadas, passando de seguida ao planeamento e posterior implementação de tal extensão quantitativa
do Alloy.
Este projecto pretende promover a evolução dos métodos formais quantitativos através da concretização de
abstracção quantitativa em Alloy, estendendo a sua base para suportar estes conceitos e assim implementá los no Alloy Analyzer
Equity research - Adidas AG
Mestrado em FinançasEste relatório centra-se na avaliação da Adidas AG, que foi elaborado de acordo com o Trabalho Final de Mestrado do Master in Finance. Este Equity Research segue a estrutura de um reporte de research recomendado pelo CFA Institute. Esta nota de research foi preparada com base na informação pública disponibilizada pela Adidas com referência a 31 de Dezembro de 2018. Assim, este reporte não comtempla eventos que possam ter ocorrido após essa data. Para chegar ao preço alvo para a empresa, o método escolhido foi o Discounted Cash Flow e a Avaliação Relativa, através de múltiplos de empresas concorrentes. O Price target obtido foi de 284.61€. Esta avaliação resulta numa recomendação de Manter. É considerada de risco médio uma vez que apesar da Adidas ser uma das duas grandes empresas desta indústria, o desaceleramento da economia surge como um potencial risco.This report is about a valuation of Adidas AG, elaborated in according with ISEG's Finance Master's Final Work. This Equity Research follows the structure of a research report recommend by the CFA Institute. The research note was prepared based on the information publicly disclosed by Adidas AG with reference to December 31st, 2018. Therefore, this report does not contemplate any events that may have occurred after this date. To obtain the Target price of the company, the method chosen was the Discounted Cash Flow (DCF) and the Relative Valuation through the multiples of peer companies. The price target reached was 284.61€. This valuation results in a Hold recommendation. It is considered of medium risk since, despite Adidas being one of the two big companies in this industry, the deceleration of the economy appears as a potential risk.info:eu-repo/semantics/publishedVersio
Simplified formulae for the estimation of the positive-sequence resistance and reactance of three-phase cables for different frequencies
Overexpression of RAC1b in follicular cell derived thyroid cancers: An activator of NF-κB pathway that contributes to thyroid tumorigenesis?
Papillary and Follicular thyroid carcinomas (PTC and FTC) are lesions derived from follicular cells. The standard therapy includes surgery and radioiodine treatment. Despite being usually associated with a good prognosis the rate of recurrence is high and a subset of patients present radioiodine refractory and non-responsive neoplasia. So, the search for new therapeutic alternatives, as well as new diagnostic/prognostic markers is highly relevant.
Our group at IPOLFG has previously shown RAC1b to be overexpressed in PTCs, being this overexpression significantly associated with poorer outcomes. RAC1b is a variant of the small GTPase RAC1 that was shown to have the ability to stimulate the canonical NF-κB regulatory pathway in colorectal cancer. NF-κB activation is associated with the tumorigenic process in several types of cancer, mainly due to its role in apoptosis evasion.
Here, we aimed to extend the study of the role of RAC1b to FTCs and further investigate the molecular mechanisms associated with RAC1b overexpression and downstream signalling in thyroid tumorigenesis.
Using the human papillary thyroid carcinoma derived cell line as in vitro model, we observed that both RAC1 and RAC1b were able to induce a significant increase on NF-κB and cyclin D1 reporter activity. A clear p65 nuclear localization was found in cells transfected with RAC1b-WT, confirming NF-κB canonical pathway activation. Consistently, we were able to observe a RAC1b-mediated decrease in IκBα (NF-κB inhibitor) protein levels.
These findings prompted us to further assess the cellular consequences of RAC1b-mediated NF-κB activation in a thyroid biological system. Our results indicated that RAC1b protected cells against apoptosis and stimulated G1/S progression, through a process involving the NF-κB pathway.
Summing up, presented findings suggest an important role of RAC1b in the progression of follicular cell derived thyroid carcinomas and point out NF-κB activation as one of the molecular mechanisms associated with RAC1b overexpression and downstream signalling in thyroid tumorigenesis
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