European Union emissions trading scheme impact on the Spanish electricity price during phase II and phase III implementation

The European Union Emissions Trading Scheme (EU ETS) is a cornerstone of the European Union's policy to combat climate change and its key tool for reducing industrial greenhouse gas emissions cost-effectively. The purpose of the present work is to evaluate the influence of CO2 opportunity cost on the Spanish wholesale electricity price. Our sample includes all Phase II of the EU ETS and the first year of Phase III implementation, from January 2008 to December 2013. A vector error correction model (VECM) is applied to estimate not only long-run equilibrium relations, but also short-run interactions between the electricity price and the fuel (natural gas and coal) and carbon prices. The four commodities prices are modeled as joint endogenous variables with air temperature and renewable energy as exogenous variables. We found a long-run relationship (cointegration) between electricity price, carbon price, and fuel prices. By estimating the dynamic pass-through of carbon price into electricity price for different periods of our sample, it is possible to observe the weakening of the link between carbon and electricity prices as a result from the collapse on CO2 prices, therefore compromising the efficacy of the system to reach proposed environmental goals. This conclusion is in line with the need to shape new policies within the framework of the EU ETS that prevent excessive low prices for carbon over extended periods of time.

Pseudo Phase Plane and Fractional Calculus Modelling of Western Global Economic Downturn

This paper applies Pseudo Phase Plane (PPP) and Fractional Calculus (FC) mathematical tools for modeling world economies. A challenging global rivalry among the largest international economies began in the early 1970s, when the post-war prosperity declined. It went on, up to now. If some worrying threatens may exist actually in terms of possible ambitious military aggression, invasion, or hegemony, countries’ PPP relative positions can tell something on the current global peaceful equilibrium. A global political downturn of the USA on global hegemony in favor of Asian partners is possible, but can still be not accomplished in the next decades. If the 1973 oil chock has represented the beginning of a long-run recession, the PPP analysis of the last four decades (1972–2012) does not conclude for other partners’ global dominance (Russian, Brazil, Japan, and Germany) in reaching high degrees of similarity with the most developed world countries. The synergies of the proposed mathematical tools lead to a better understanding of the dynamics underlying world economies and point towards the estimation of future states based on the memory of each time series.

Fractional Dynamics Representation in the Pseudo Phase Plane

Proceedings of the 10th Conference on Dynamical Systems Theory and Applications

Formation Control Driven by Cooperative Object Tracking

In this paper we introduce a formation control loop that maximizes the performance of the cooperative perception of a tracked target by a team of mobile robots, while maintaining the team in formation, with a dynamically adjustable geometry which is a function of the quality of the target perception by the team. In the formation control loop, the controller module is a distributed non-linear model predictive controller and the estimator module fuses local estimates of the target state, obtained by a particle filter at each robot. The two modules and their integration are described in detail, including a real-time database associated to a wireless communication protocol that facilitates the exchange of state data while reducing collisions among team members. Simulation and real robot results for indoor and outdoor teams of different robots are presented. The results highlight how our method successfully enables a team of homogeneous robots to minimize the total uncertainty of the tracked target cooperative estimate while complying with performance criteria such as keeping a pre-set distance between the teammates and the target, avoiding collisions with teammates and/or surrounding obstacles.

Controlo inteligente de um Sistema de Levitação Magnética

A levitação magnética tem sido um tema bastante investigado sobretudo devido à sua utilização em sistemas ferroviários de transportes. É o método ideal quando existe a necessidade em aplicações de restringir do contacto físico, ou a conveniência, em termos energéticos, de eliminar o atrito. O princípio de funcionamento é simples, um eletroíman cria uma força sobre um objeto ferromagnético que contraria a gravidade. Contudo um sistema de levitação por atração é instável e não linear, o que significa a necessidade de implementar um controlador para satisfazer as características de estabilidade desejadas. Ao longo deste projeto serão descritos os procedimentos teóricos e práticos que foram tomados na criação de um sistema de levitação eletromagnética. Desde a conceção física do sistema, como escolha do sensor, condicionamento de sinal ou construção do eletroíman, até aos procedimentos matemáticos que permitiram a modelação do sistema e criação de controladores. Os controladores clássicos, como o PID ou em avanço de fase, foram projetados através da técnica do Lugar Geométrico de Raízes. No projeto do controlador difuso, pelo contrário não se fez uso da modelação do sistema ou de qualquer relação matemática entre as variáveis. A utilização desta técnica de controlo destacou-se pela usa simplicidade e rapidez de implementação, fornecendo um bom desempenho ao sistema. Na parte final do relatório os resultados obtidos pelos diferentes métodos de controlo são analisados e apresentadas as respetivas conclusões. Estes resultados revelam que para este sistema, relativamente aos outros métodos, o controlador difuso apresenta o melhor desempenho tanto ao nível da resposta transitória, como em regime permanente.

Espresso beverages of pure origin coffee: Mineral characterization, contribution for mineral intake and geographical discrimination

Espresso coffee beverages prepared from pure origin roasted ground coffees from the major world growing regions (Brazil, Ethiopia, Colombia, India, Mexico, Honduras, Guatemala, Papua New Guinea, Kenya, Cuba, Timor, Mussulo and China) were characterized and compared in terms of their mineral content. Regular consumption of one cup of espresso contributes to a daily mineral intake varying from 0.002% (sodium; Central America) to 8.73% (potassium; Asia). The mineral profiles of the espresso beverages revealed significant inter- and intra-continental differences. South American pure origin coffees are on average richer in the analyzed elements except for calcium, while samples from Central America have generally lower mineral amounts (except for manganese). Manganese displayed significant differences (p < 0.05) among the countries of each characterized continent. Intercontinental and inter-country discrimination between the major world coffee producers were achieved by applying canonical discriminant analysis. Manganese and calcium were found to be the best chemical descriptors for origin.

Polycyclic aromatic hydrocarbons: levels and phase distributions in preschool microenvironment

This work aims to characterize levels and phase distribution of polycyclic aromatic hydrocarbons (PAHs) in indoor air of preschool environment and to assess the impact of outdoor PAH emissions to indoor environment. Gaseous and particulate (PM1 and PM2.5) PAHs (16 USEPA priority pollutants, plus dibenzo[a,l]pyrene, and benzo[j]fluoranthene) were concurrently sampled indoors and outdoors in one urban preschool located in north of Portugal for 35 days. The total concentration of 18 PAHs (ΣPAHs) in indoor air ranged from 19.5 to 82.0 ng/m3; gaseous compounds (range of 14.1–66.1 ng/m3) accounted for 85% ΣPAHs. Particulate PAHs (range 0.7–15.9 ng/m3) were predominantly associated with PM1 (76% particulate ΣPAHs) with 5-ring PAHs being the most abundant. Mean indoor/outdoor ratios (I/O) of individual PAHs indicated that outdoor emissions significantly contributed to PAH indoors; emissions from motor vehicles and fuel burning were the major sources.

Reliability of Two Methods for Identifying the Postural Phase of Gait Initiation in Healthy and Post-stroke Subjects

This study aims to compare two methods of assessing the postural phase of gait initiation as to intrasession reliability, in healthy and post-stroke subjects. As a secondary aim, this study aims to analyse anticipatory postural adjustments during gait initiation based on the centre of pressure (CoP) displacements in post-stroke participants. The CoP signal was acquired during gait initiation in fifteen post-stroke subjects and twenty-three healthy controls. Postural phase was identified through a baseline-based method and a maximal displacement based method. In both healthy and post-stroke participants higher intra-class correlation coefficient and lower coefficient of variation values were obtained with the baseline-based method when compared to the maximal displacement based method. Post-stroke participants presented decreased CoP displacement backward and toward the first swing limb compared to controls when the baseline-based method was used. With the maximal displacement based method, there were differences between groups only regarding backward CoP displacement. Postural phase duration in medial-lateral direction was also increased in post-stroke participants when using the maximal displacement based method. The findings obtained indicate that the baseline-based method is more reliable detecting the onset of gait initiation in both groups, while the maximal displacement based method presents greater sensitivity for post-stroke participants.

Ankle antagonist coactivation in the double-support phase of walking: Stroke vs. healthy subjects

Introduction: Lesions at ipsilateral systems related to postural control at ipsilesional side, may justify the lower performance of stroke subjects during walking. Purpose: To analyse bilateral ankle antagonist coactivation during double-support in stroke subjects. Methods: Sixteen (8 females; 8 males) subjects with a first isquemic stroke, and twenty two controls (12 females; 10 males) participated in this study. The double support phase was assessed through ground reaction forces and electromyography of ankle muscles was assessed in both limbs. Results: Ipsilesional limb presented statistical significant differences from control when assuming specific roles during double support, being the tibialis anterior and soleus pair the one in which this atypical behavior was more pronounced. Conclusion: The ipsilesional limb presents a dysfunctional behavior when a higher postural control activity was demanded.

Modelos Teóricos de Difusão Dérmica: abordagens matemáticas e computacionais para terapias transdérmicas da Obesidade

É de senso comum que os nutrientes são fundamentais à vida e que a subnutrição leva à acumulação de gorduras que pode chegar a casos de obesidade, tendo como consequência inúmeras complicações de saúde. Diferentes estruturas neuroanatómicas do cérebro têm um papel essencial no comportamento digestivo. A ação de várias moléculas de sinalização (hormonas, neurotransmissores e neuropéptidos) resulta na regulação da ingestão de alimentos, sendo que, por exemplo, algumas hormonas podem aumentar a sensação de saciedade podendo diminuir o apetite e a ingestão calórica. A descoberta de hormonas envolvidas no balanço energético proporcionou novas oportunidades para desenvolver meios para o tratamento da obesidade. A transferência de medicação antiobesidade por via tópica ou transdérmica é um desafio pois a pele funciona como uma barreira natural e protetora. Sendo uma barreira com uma grande área de superfície e de fácil acessibilidade, a pele tem potencial interesse na libertação de fármacos específicos a cada terapia. Vários métodos têm sido estudados de modo a permitir um aumento da permeabilidade de moléculas terapêuticas para o interior da pele e através da pele. As biotecnologias transdérmicas são um campo de interesse cada vez maior, devido as aplicações dérmicas e farmacêuticas que lhes estão subjacentes. Existem vários modelos computacionais e matemáticos em uso que permite uma visão mais abrangente de puros dados experimentais e até mesmo permite a extrapolação prática de novas metodologias de difusão dérmica. Contudo, eles compreendem uma complexa variedade de teorias e suposições que atribuem a sua utilização para situações específicas. Este trabalho, primeiramente analisa, de forma extensiva, as várias metodologias teóricas para o estudo da difusão dérmica e sistematiza as suas características, realizando depois a fase prévia duma nova abordagem computacional para o estudo da difusão dérmica, que determina características microscópicas de moléculas capazes de provocar a perda de peso, tais como a Leptina e/ou os seus agonistas.

Focal Malignant Liver Lesions: Diagnosis by Dynamic Incremental CT, Early Phase

The purpose of our study was to evaluate the accuracy of dynamic incremental bolus-enhanced conventional CT (DICT) with intravenous contrast administration, early phase, in the diagnosis of malignancy of focal liver lesions. A total of 122 lesions were selected in 74 patients considering the following criteria: lesion diameter 10 mm or more, number of lesions less than six per study, except in multiple angiomatosis and the existence of a valid criteria of definitive diagnosis. Lesions were categorized into seven levels of diagnostic confidence of malignancy compared with the definitive diagnosis for acquisition of a receiver-operator-characteristic (ROC) curve analysis and to determine the sensitivity and specificity of the technique. Forty-six and 70 lesions were correctly diagnosed as malignant and benign, respectively; there were 2 false-positive and 4 false-negative diagnoses of malignancy and the sensitivity and specificity obtained were 92 and 97%. The DICT early phase was confirmed as a highly accurate method in the characterization and diagnosis of malignancy of focal liver lesions, requiring an optimal technical performance and judicious analysis of existing semiological data.

Effects of vitamin C supplementation on acute phase Chagas disease in experimentally infected mice with Trypanosoma cruzi QM1 strain

The tissue changes that occur in Chagas disease are related to the degree of oxidative stress and antioxidant capacity of affected tissue. Studies with vitamin C supplementation did not develop oxidative damage caused by Chagas disease in the host, but other studies cite the use of peroxiredoxins ascorbate - dependent on T. cruzi to offer protection against immune reaction. Based on these propositions, thirty "Swiss" mice were infected with T. cruzi QM1 strain and treated with two different vitamin C doses in order to study the parasitemia evolution, histopathological changes and lipid peroxidation biomarkers during the acute phase of Chagas disease. The results showed that the parasite clearance was greater in animals fed with vitamin C overdose. There were no significant differences regarding the biomarkers of lipid peroxidation and inflammatory process or the increase of myocardium in animals treated with the recommended dosage. The largest amount of parasite growth towards the end of the acute phase suggests the benefit of high doses of vitamin C for trypomastigotes. The supplementation doesn't influence the production of free radicals or the number of amastigote nests in the acute phase of Chagas disease.

EXPERIMENTAL INFECTION WITH Toxocara cati IN PIGS: MIGRATORY PATTERN AND PATHOLOGICAL RESPONSE IN EARLY PHASE

Experimental inoculations of approximately 100,000 infective Toxocara cati larval eggs were done in twelve pigs. The T. cati eggs used for inoculation were collected from cat's feces. Another group of three pigs served as an uninfected control. Groups of infected pigs were euthanized at seven, 14, 21, and 28 days post-inoculation (dpi). Tissue samples were taken for digestion and histopathology changes in early phase. The number of larvae recovered from the lungs peaked at seven and 14 dpi and were also present at 21, and 28 dpi. Larvae of T. cati were present in the lymph nodes of the small and large intestine at seven, 14, and 28 dpi and at seven, 14, 21, and 28 dpi respectively. In other studied tissues, no larvae or less than one larva per gram was detected. The pathological response observed in the liver and lungs at seven and 14 dpi, showed white spots on the liver surface and areas of consolidation were observed in the lungs. The lungs showed an inflammatory reaction with larvae in center at 28 dpi. In the liver we observed periportal and perilobular hepatitis. The lymph nodes of the intestines displayed eosinophil lymphadenitis with reactive centers containing parasitic forms in some of them. The granulomatous reaction was not observed in any tissues. The role of the other examined tissues had less significance. The relevance of this parasite as an etiological agent that leads to disease in paratenic hosts is evident.

Artroplastia Unicompartimental do Joelho Oxford Phase 3. Resultados a Médio Prazo

Introdução: A artroplastia unicompartimental evoluiu nos últimos 40 anos, sendo hoje em dia considerada uma estratégia cirúrgica apropriada para a osteoartrose do compartimento interno da articulação do joelho. Desenvolvimentos nos instrumentos cirúrgicos, desenho do implante, abordagem cirúrgica e selecção dos doentes levaram a uma grande melhoria dos resultados pós-operatórios e aumento da longevidade das próteses unicompartimentais do joelho. Comparada com a prótese total, tem como vantagens a preservação óssea, menos complicações pós‐operatórias (perdas sanguíneas, dor pós‐operatória, taxa de infecção, trombose venosa profunda (TVP) e tromboembolismo pulmonar (TEP)), manutenção da normal cinemática do joelho, alta precoce e reabilitação mais rápida. A prótese unicompartimental Oxford phase 3 foi introduzida em 1998 e é uma prótese cimentada com menisco móvel de polietileno. Material e Métodos: Foi realizado um estudo retrospectivo das artroplastias unicompartimentais do joelho Oxford phase 3 realizadas no nosso serviço. Desde 2006 realizaram-se 37 artroplastias unicompartimentais (num total de 34 doentes). Sete dos quais não compareceram à avaliação pós-operatória e por isso foram excluídos do estudo. Todos os doentes incluídos no estudo foram avaliados clínica e radiograficamente. Foram revistos os processos de consulta e do internamento. Registou-se a idade,sexo, classificação ASA (American Society of Anesthesiologists), grau de satisfação, flexão‐extensão actual, Oxford knee score pré e pós‐operatório e alterações radiográficas a salientar. Resultados: O follow‐up médio foi de 47 meses (10 ‐ 83 meses). A idade média dos doentes é de 64 anos, com predomínio do sexo feminino. O ASA médio foi de 2,4. Um dos doentes foi submetido a conversão para artroplastia total do joelho por falência do componente tibial. Há 2 doentes não satisfeitos com a cirurgia (que corresponde aos doentes em que o Oxford knee score piorou). Há 1 doente pouco satisfeito e 23 satisfeitos ou muito satisfeitos. Todos os doentes conseguem fazer extensão completa e a média de flexão é 111º. A média do Oxford knee score pré‐operatório é de 17,4 (5 ‐ 30) e pós‐operatório é 36,6 (11 ‐ 48). Radiologicamente, há uma média de desvio em varo de 1,68º (varo 8º ‐ valgo 5º). Ocorreu artrose femoro‐tibial externa em três casos (dois dos quais também com artrose femoro‐patelar),um caso com slope tibial exagerado (19º), um caso com componente femoral em varo (15º), um caso com componente tibial demasiado grande com protusão interna, um caso de extrusão do menisco de polietileno, um caso com o componente tibial em valgo e um caso com falência deste (descelamento?) com provável necessidade de conversão para artroplastia total. Dos doentes não avaliados não há registo de conversão para artroplastia total do joelho ou outras complicações. Discussão: A larga maioria dos doentes encontram‐se satisfeitos ou muito satisfeitos, havendo uma melhoria do Oxford knee score para mais do dobro. Não se registaram complicações pós‐operatórias imediatas. Das artropastias unicompartimentas realizadas só uma foi convertida para artroplastia total e outra provavelmente a necessitar de conversão, com uma longevidade de 94,6% aos 47 meses (em média). Conclusão: A artroplastia unicompartimental do joelho demonstrou‐se uma excelente opção para doentes com osteoartrose não-inflamatória do compartimento interno do joelho. Para se obterem bons resultados os doentes devem ser criteriosamente seleccionados. Considerando a curva de aprendizagem necessária para o sucesso da cirurgia, a pouca experiência da maioria dos cirurgiões que colocaram as próteses não teve influência nos resultados finais, estando de acordo com a literatura existente, provando que a artroplastia unicompartimental do joelho tem bons resultados clínicos e funcionais. Um maior tempo de follow-up será necessário para se avaliar a longevidade das próteses unicompartimentais.