32 research outputs found
Essays on the economics of the energy mix diversification in the Transport Sector
The analysis of the consequences of the diversification of the Transport Sector energy mix is
the main focus of this thesis. As a sector highly powered by fossil fuels, the promotion of
alternative energy sources such as electricity and renewable fuels has to be pursued to reduce
the use of oil, and consequently cut greenhouse gases emissions. However, currently, the
alternative sources are faced with several challenges. To address some of these challenges,
this thesis performs four analyses organized into three main parts. In the first one, the
interactions between both conventional and alternative transports’ energy sources, economic
growth and carbon dioxide emissions have been examined. Two essays have been carried out in
the first part, to achieve these objectives. The recent methods of Panel-Vector Autoregressive
and the Autoregressive Distributed lag models have been applied. The main findings suggest
that the electricity use in the transport sector only contributes to reducing GHG emissions if
this electricity is coming from renewable sources. At the same time, the alternative energy
sources could compromise the economic growth highlighting that their cost-effectiveness must
be enlarged.
With adequate policy supporting, the penetration of the electricity in transport sector could
have a great potential in, for instance, storing renewable electricity, improving renewable
electricity utilisation. For that, the deployment of electricity on the road transportation is
required. These evidences have definitively motivated the second and third main parts of this
thesis. They are focused on the main challenges that the electric mobility on road
transportation is faced: the penetration of electric vehicles in the automotive market and the
impact of these vehicles on the electricity system management and renewables integration.
Thus, the second part of this thesis aims to analyse the driving factors of electric vehicles
adoption. This analysis goes further by distinguishing the adoption drivers of 100% electric
vehicles, also known as battery electric vehicles, and plug-in electric vehicles. The factors
analysed include: political, social, economic, environmental, and technical. A Panel-Corrected
Standard Errors (PCSE) estimator is used for European Union countries and the robustness of
the results has been confirmed by employing a Seemingly Unrelated Regression (SUR) method.
Actually, the main challenge for both 100% electric vehicles and plug-in electric vehicles
adoption is the technological progress of the batteries. Furthermore, this analysis highlights
that the policymaking should be focused on each type of vehicle technology instead of electric
vehicles as a whole. In line with the findings of the first part of this thesis, countries with high
endogenous potential should promote more 100% electric vehicles than plug-in electric vehicles
to take advantage of the renewable electricity. While countries with low renewable potential
should promote more plug-in electric vehicles. The policies supporting electric mobility have been effective in the 100% electric vehicles market share enlargement, but not for plug-in
electric vehicles.
With an appropriated policy support and technological development, the 100% electric vehicles
could contribute to increasing the efficiency of the electricity system and renewables
integration. These evidences constitute the main motivation for the third part of this thesis.
Therefore, the main objective of the third part is to analyse the drivers of both peak electricity
demand and renewables integration, providing special attention to the role played by battery
electric vehicles to this equilibrium. Both Panel-Corrected Standard Errors and Driscoll-Kraay
estimators have been applied for European Union countries. Different models’ specifications
have been used to confirm the robustness of the results found. This part highlights that the
deployment of the 100% electric vehicles has led to a decrease of the peak electricity demand,
which is indeed a desirable effect. Still, it should deserve further attention since the
deployment of the large amounts of battery electric vehicles could modify this effect. At the
same time, the 100% electric vehicles have not contributed to renewables integration. The
policies focused on demand side management have been effective in integrating renewables in
contrast to their lack of success in reducing peak electricity demand. The policymakers should
design demand side management efficient policies to reduce the peak load demand. The
promotion of Demand Response measures, such as differentiated electricity tariffs in peak
periods and out-off peak periods could be an efficient way to achieve it.A presente tese foca-se em analisar as consequências da diversificação do mix de energia no
sector dos transportes. Este sector é intensivo no consumo de combustíveis fósseis e
consequentemente, é responsável por elevados níveis de emissões de gases com efeito de
estufa. De forma a mitigar o seu impacto ambiental, o uso de fontes de energia alternativas,
tais como eletricidade e combustíveis renováveis deve ser incentivado. Contudo, existem
inúmeros desafios associados à utilização destas fontes. Com o intuito de abordar alguns dos
desafios enfrentados, a presente tese realiza quatro ensaios, organizados em três partes. Na
parte inicial, são estudadas as interações entre o consumo de fontes de energia convencionais
e alternativas no sector dos transportes, bem como a sua relação com o crescimento económico
e com as emissões de dióxido de carbono. De forma a analisar essas interações, foram realizados
dois ensaios. Neles, foram aplicadas duas metodologias recentes de análise de dados em painel:
Vetor Autorregressivo em Painel (Panel Vector Autoregressive - PVAR) e o Modelo
Autorregressivo com Desfasamento Distribuído (Autoregressive Distributed Lag - ARDL). Os
principais resultados sugerem que o consumo de eletricidade no setor dos transportes será
benéfico para o ambiente, se essa eletricidade for gerada a partir de fontes de energia
renováveis. Enquanto isso, as fontes alternativas poderão estar a comprometer o crescimento
económico, enfatizando que o custo-benefício dessas fontes deve ser melhorado.
A introdução de eletricidade no mix energético do setor dos transportes poderá ter um grande
potencial em, por exemplo, possibilitar o armazenamento de eletricidade renovável
aumentando assim a sua utilização. Para isso, as políticas devem promover o carregamento dos
veículos quando existe excesso de geração de eletricidade renovável. Para que seja possível
capturar esses benefícios, é necessária a implementação de eletricidade no transporte
rodoviário. Definitivamente, estas evidências motivaram a segunda e terceira parte desta tese.
As mesmas incidem nos principais desafios que a mobilidade elétrica rodoviária enfrenta: a
penetração de veículos elétricos no mercado automóvel e o impacto dos veículos elétricos, quer
na gestão do sistema elétrico quer na integração de energias renováveis. Assim, a segunda parte
pretende analisar os fatores que suportam a adoção de veículos elétricos, abordando o seu
papel individualmente tanto nos veículos 100% elétricos como nos híbridos plug-in. Fatores
políticos, sociais, económicos, ambientais e técnicos foram incluídos e analisados. A Regressão
Linear com Erros Padrão Corrigidos para Painel (Panel Corrected Standard Errors - PCSE) foi
aplicada para analisar países da União Europeia e a robustez dos resultados foi comprovada
mediante a aplicação de modelos de Regressão Aparentemente não Relacionada (Seemingly
Unrelated Regression - SUR). A análise mostrou que o progresso tecnológico das baterias tem
se revelado como um dos principais desafios para a implementação dos veículos 100% elétricos
e dos híbridos plug-in. Além disso, este ensaio realça que as políticas devem ser focadas em cada tipo de veículo individualmente em vez de concentradas na mobilidade elétrica como um
todo. Tendo em conta os resultados obtidos na primeira parte desta tese, países com elevado
potencial em energias renováveis devem promover mais os veículos 100% elétricos do que os
veículos híbridos plug-in, de forma a conseguir tirar maior vantagem da utilização intensiva de
eletricidade renovável. Pelo contrário, países com baixo potencial em renováveis devem
promover mais a utilização de híbridos plug-in.
Poderão os veículos 100% elétricos contribuir para o aumento da eficiência do sistema elétrico
e para a integração de renováveis? Esta curiosidade constitui-se como a essencial motivação
para a terceira parte. O seu principal objetivo é analisar os impulsionadores do pico de consumo
de eletricidade e de integração de renováveis, dando especial foco ao papel que os veículos
100% elétricos desempenham nesse equilíbrio. A Regressão Linear com Erros Padrão Corrigidos
para Painel (Panel Corrected Standard Errors - PCSE) e a Regressão com Erros Padrão de
Driscoll-Kraay (Regression with Driscoll-Kraay standard errors) foram os modelos aplicados
para analisar países da União Europeia. Foram testadas diferentes especificações nos modelos,
confirmando assim a robustez dos resultados. Esta parte salienta que o aumento da quota de
mercado de veículos elétricos gera um decréscimo do pico de consumo de eletricidade, o que
é, na verdade, um efeito desejável num sistema electroprodutor. Este efeito deve, no entanto,
merecer atenção dos decisores de políticas, uma vez que, a implementação de um elevado
número de veículos 100% elétricos, poderá alterar este efeito colocando picos de consumo em
outros períodos. Importa salientar também que os resultados sugerem que as políticas aplicadas
para a gestão ativa da procura (Demand Side Management - DSM) de eletricidade têm sido
efetivas na integração de renováveis, mas não têm contribuído para reduzir o pico de consumo.
Os decisores de políticas devem delinear políticas de DSM eficientes, promovendo, por
exemplo, medidas de resposta da procura, tais como tarifas de eletricidade com preços
diferenciados entre períodos de pico e períodos fora de pico
The Spanish evidence
This study focuses on the analysis of interactions between electricity generation sources under both the Special Regime and the Ordinary Regime in Spain, and their relationships with economic activity. The time span comprises data from January 2003 to September 2014. The Toda-Yamamoto causality test is carried out to check causality relationships. Both short- and long-run effects are assessed, by using the ARDL bounds test approach. Overall, the results reveal strong internal consistency when comparing the ARDL results with the causality analysis. On the one hand, a unidirectional causality running from the ordinary regime to the special regime was found. On the other hand, with respect to the ordinary regime there is empirical evidence for the energy-growth hypothesis. In the meantime, the special regime contributes to hampering economic growth in Spain.A presente dissertação estuda a interação entre fontes de geração de eletricidade através da produção sob regime especial e sob regime ordinário e a sua relação com a atividade económica. O estudo utiliza dados mensais de Janeiro de 2003 até Setembro de 2014. O teste de causalidade Toda-Yamamoto foi executado para averiguar quais as relações de causalidade existentes entre as variáveis. A metodologia ARDL bounds test permitiu capturar os efeitos de curto e de longo prazo em separado. Globalmente, os resultados das causalidades revelam grande consistência quando comparados com os resultados da metodologia ARDL. Os resultados sugerem a existência de uma causalidade unidirecional da produção de eletricidade em regime ordinário para o regime especial. Analisando o tradicional nexus pode-se concluir que a hipótese de feedback é verificada entre o regime ordinário e a atividade económica. Por outro lado, verifica-se também que o regime especial é um entrave ao crescimento da atividade económica
Guia de Apoio ao Voluntariado do Instituto Politécnico de Leiria
Com a consciência dos enormes desafios que hoje o mundo nos coloca, estarmos atentos às necessidades do outro e procurando dar-lhes resposta, constitui, só por si, um elevado compromisso social e de perceção coletiva, permitindo-nos ainda amplificar a nossa compreensão das desigualdades existentes na sociedade. A prática do voluntariado é uma componente importante na construção desta sociedade, pelo que importa dinamizar as ações de voluntariado e incentivar a apresentação de propostas para a realização de ações desta natureza. O Guia de Apoio ao Voluntariado do Instituto Politécnico de Leiria pretende ser um manual de ajuda a uma prática cívica de todos no bem-estar da nossa comunidade.N/
Anti-inflammatory and antioxidant nanostructured cellulose membranes loaded with phenolic-based ionic liquids for cutaneous application
The utilization of natural compounds, such as phenolic acids and biopolymers, in the healthcare domain is gaining increasing attention. In this study, bacterial nanocellulose (BC) membranes were loaded with ionic liquids (ILs) based on phenolic acids. These ionic compounds, with improved solubility and bioavailability, were prepared by combining the cholinium cation with anions derived from caffeic, ellagic and gallic acids. The obtained BC-ILs membranes were homogeneous, conformable and their swelling ability agreed with the solubility of each IL. These membranes revealed a controlled ILs dissolution rate in the wet state and high antioxidant activity. In vitro assays performed with Raw 264.7 macrophages and HaCaT keratinocytes revealed that these novel BC-ILs membranes are non-cytotoxic and present relevant anti-inflammatory properties. Diffusion studies with Hanson vertical diffusion cells showed a prolonged release profile of the ILs from the BC membranes. Thus, this work, successfully demonstrates the potential of BC-ILs membranes for skin treatment.publishe
Deep Eutectic Solvents as alternative solvents in Antimicrobial Photodynamic Therapy
info:eu-repo/semantics/publishedVersio
Pawedness trait test (PaTRaT) : a new paradigm to evaluate paw preference and dexterity in rats
Pawedness Trait Test (PaTRaT)-A New Paradigm to Evaluate Paw Preference and Dexterity in RatsIn rodents, dexterity is commonly analyzed in preference paradigms in which animals are given the chance to use either the left or the right front paws to manipulate food. However, paw preference and dexterity at population and individual levels are controversial as results are incongruent across paradigms. We have therefore developed a semi-quantitative method-the pawdeness trait test (PaTRaT)-to evaluate paw preference degree in rats. The PaTRaT consists in a classification system, ranging from +4 to 4 where increasingly positive and negative values reflect the bias for left or right paw use, respectively. Sprague-Dawley male rats were confined into a metal rectangular mesh cylinder, from which they can see, smell and reach sugared rewards with their paws. Due to its size, the reward could only cross the mesh if aligned with its diagonal, imposing additional coordination. Animals were allowed to retrieve 10 rewards per session in a total of four sessions while their behavior was recorded. PaTRaT was repeated 4 and 8 weeks after the first evaluation. To exclude potential bias, rats were also tested for paw fine movement and general locomotion in other behavioral paradigms as well as impulsivity (variable delay-to-signal, VDS), memory and cognitive flexibility (water maze). At the population level 54% of the animals presented a rightward bias. Individually, all animals presented marked side-preferences, >2 and <-2 for left-and right-sided bias, respectively, and this preference was stable across the three evaluations. Inter-rater consistency was very high between two experienced raters and substantial when two additional inexperienced raters were included. Left-and right-biased animals presented no differences in the ability to perform fine movements with any of the forelimbs (staircase) and general locomotor performance. Additionally, these groups performed similarly in executive function and memory tasks. In conclusion, PaTRaT is able to reliably classify rats' pawedness direction and degree.This work has been funded by the European Regional Development Fund (FEDER), through the Competitiveness Factors Operational Programme (COMPETE) and the Northern Portugal Regional Operational Programme (NORTE 2020) under the Portugal 2020 Partnership Agreement (project NORTE-01-0145-FEDER-000023). It was also funded by National funds, through the Foundation for Science and Technology (Fundacao para a Ciencia e a Tecnologia, FCT), under the scope of the projects POCI-01-0145-FEDER-007038 and PTDC/NEU-SCC/5301/2014. Researchers were supported by FCT grant numbers SFRH/BD/109111/2015 (AMC), SFRH/BD/52291/2013 (ME via Inter-University Doctoral Programme in Ageing and Chronic Disease, PhDOC), PD/BD/114120/2015 (SPN via PhDOC), SFRH/BD/89936/2012 (SB), PD/BD/114117/2015 (MRG via PhDOC) and SFRH/BPD/80118/2011 (HL-A).info:eu-repo/semantics/publishedVersio
A comprehensive assessment of the transcriptome of cork oak (Quercus suber) through EST sequencing
Background: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management.
Results: We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of ~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at http://www.corkoakdb.org.
Conclusions: This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.Peer Reviewe
Dinâmicas de (investig)ação em contextos de promoção da língua portuguesa: a presença do CIDTFF na rede Camões, I.P.
Sem resumo disponível.publishe
Drivers and barriers in the transition from a linear economy to a circular economy
A paradigm shift from a linear economy to a circular economy is crucial to reduce pressure on the environment and to improve the security of supply of primary raw materials. Under this new paradigm, governed by the imperatives of “reduce, reuse, and recycle”, the extraction of primary resources is minimised by extending the useful life of existing resources and materials. This paper seeks to identify the drivers and barriers of this circularisation and provide guidance for effective policies to hasten the transition to it. The innovative contribution made by this paper to this area of research is the empirical evidence it provides on the role played by economic, social, and environmental factors in the transition to a circular economy. To achieve this, yearly data from 2010 to 2019, for a panel of 19 European Union countries were analysed employing a Panel-Corrected Standard Errors estimator, which was shown to be an appropriate estimator for the data's characteristics. The circular material use rate was used as a proxy for the circular economy. The main findings suggest that the age distribution of a country is a significant predictor of a circular economy. Older people tend to be reluctant to change their behaviour, while young people are more inclined to move away from the so-called ‘take-make-waste’ extractive industrial model. Policies directed to older people to sensibilize them on the benefits and importance of a circular economy are thus required. When per capita income increases, the propensity to accept products containing recycled materials decreases. This finding merits the particular attention of policymakers. In turn, income inequality makes moving toward a circular economy more difficult. Those in the middle-income bracket are more likely to exhibit green behaviour, which implies that they are more aware of environmental issues.info:eu-repo/semantics/publishedVersio
The substitution of fossil fuels in the US transportation energy mix: Are emissions decoupling from economic growth?
Environmental protection should be a primary factor in the evolution of the dominant transportation energy paradigm. This paper takes a fresh approach to this issue by analysing the relationship between conventional and alternative energy sources in transportation, economic growth and emissions. This is a previously unexplored topic in literature, particularly in the United States of America (US), which is analysed in detail here. The paper makes a further contribution to the field by an analysis, based on Tapio indicator, of decoupling between eco-nomic growth and CO2 emissions resulting from both overall energy consumption and energy consumption by the transportation. Empirically, this paper applies an Autoregressive Distributed Lag model by using monthly data from January 2007 to September 2018. A Decoupling Indicator was calculated by using yearly data from 2006 to 2018. Main findings suggest that alternative energy sources have not yet reducing the dependence of the transportation sector on fossil fuels. Additionally, although the use of renewable fuels by transportation reduces CO2 emissions, it also hampers economic growth, while economic growth has a negative effect on emissions. This finding is further supported by the decoupling statuses found. I Improvements in energy efficiency appear to have been effective for environmental protection.info:eu-repo/semantics/publishedVersio