N-acetyl-β -d-glucosaminidase activity in feral Carcinus maenasexposed to cadmium

Cadmium is a priority hazardous substance, persistent in the aquatic environment, with the capacity to interfere with crustacean moulting. Moulting is a vital process dictating crustacean growth, reproduction and metamorphosis. However, for many organisms, moult disruption is difficult to evaluate in the short term, what limits its inclusion in monitoring programmes. N-acetyl-β-d-glucosaminidase (NAGase) is an enzyme acting in the final steps of the endocrine-regulated moulting cascade, allowing for the cast off of the old exoskeleton, with potential interest as a biomarker of moult disruption. This study investigated responses to waterborne cadmium of NAGase activity of Carcinus maenas originating from estuaries with different histories of anthropogenic contamination: a low impacted and a moderately polluted one. Crabs from both sites were individually exposed for seven days to cadmium concentrations ranging from 1.3 to 2000 μg/L. At the end of the assays, NAGase activity was assessed in the epidermis and digestive gland. Detoxification, antioxidant, energy production, and oxidative stress biomarkers implicated in cadmium metabolism and tolerance were also assessed to better understand differential NAGase responses: activity of glutathione S-transferases (GST), glutathione peroxidase (GPx) glutathione reductase (GR), levels of total glutathiones (TG), lipid peroxidation (LPO), lactate dehydrogenase (LDH), and NADP+-dependent isocitrate dehydrogenase (IDH). Animals from the moderately polluted estuary had lower NAGase activity both in the epidermis and digestive gland than in the low impacted site. NAGase activity in the epidermis and digestive gland of C. maenas from both estuaries was sensitive to cadmium exposure suggesting its usefulness for inclusion in monitoring programmes. However, in the digestive gland NAGase inhibition was found in crabs from the less impacted site but not in those from the moderately contaminated one. Altered glutathione levels were observed in cadmium-treated crabs from the contaminated site possibly conferring enhanced tolerance to these animals through its chelator action. Investigation of enhanced tolerance should thus be accounted for in monitoring programmes employing NAGase as biomarker to avoid data misinterpretation.

Stochasticity favoring the effects of the R&D strategies of the firms

We present stochastic dynamics on the production costs of Cournot competitions, based on perfect Nash equilibria of nonlinear R&D investment strategies to reduce the production costs of the firms at every period of the game. We analyse the effects that the R&D investment strategies can have in the profits of the firms along the time. We observe that, in certain cases, the uncertainty can improve the effects of the R&D strategies in the profits of the firms due to the non-linearity of the profit functions and also of the R&D parameters.

Cournot duopoly with competition in the R&D expenditures

We present a new R&D investment in a Cournot Duopoly model and we analyze the different possible types of Nash R&D investments. We observe that the new production costs region can be decomposed in three economical regions, depending on the Nash R&D investment, showing the relevance of the use of patents in new technologies.

Forest management: different criteria – equal sustainability

From the forest management perspective, many definitions have been proposed for the concept of forest sustainability. Despite this apparent diversity, most of them converge on the same aspects. In this work we developed a comparative approach of two distinct forest management methodologies used in Europe, more precisely in Slovenia and in Portugal. Although in each case study differences in vegetation, climate and pedological characteristics are evident, we were able to show some peculiar aspects of both the Slovenian and the Portuguese examples. This study also dealt with the evolution of the term sustainability in the last decades and how it played an important role for forest management options.

Longitudinal analysis of tumor marker CEA of breast cancer patients from Braga's hospital

Allied to an epidemiological study of population of the Senology Unit of Braga’s Hospital that have been diagnosed with malignant breast cancer, we describe the progression in time of repeated measurements of tumor marker Carcinoembryonic antigen (CEA). Our main purpose is to describe the progression of this tumor marker as a function of possible risk factors and, hence, to understand how these risk factors influences that progression. The response variable, values of CEA, was analyzed making use of longitudinal models, testing for different correlation structures. The same covariates used in a previous survival analysis were considered in the longitudinal model. The reference time used was time from diagnose until death from breast cancer. For diagnostic of the models fitted we have used empirical and theoretical variograms. To evaluate the fixed term of the longitudinal model we have tested for a changing point on the effect of time on the tumor marker progression. A longitudinal model was also fitted only to the subset of patients that died from breast cancer, using the reference time as time from date of death until blood test.

ETICS como sistema de reabilitação de fachadas

O presente relatório retrata o estágio curricular desenvolvido no segundo ano do Mestrado em Engenharia Civil - Ramo de Construções do Instituto Superior de Engenharia do Porto. O relatório fará primeiramente uma abordagem às principais tarefas desempenhadas durante o estágio bem como uma abordagem à empresa adjudicatária da obra em análise. Seguidamente apresenta-se a obra em que se desenvolveu o estágio, “Requalificação e Reabilitação de Vila D��� Este Fase II”, onde será feita uma descrição do estado em que se encontravam os edifícios antes de serem intervencionados, bem como das intervenções efetuadas. Na sequência da apresentação da obra, será feita uma abordagem ao tema de estudo deste relatório, o Sistema ETICS. Este sistema com crescente procura no mercado, tem muitos parâmetros aos quais deve obedecer, pelo que neste relatório serão apresentados todos os aspetos considerados relevantes à sua correta execução. Para terminar serão verificadas as melhorias impostas por este Sistema. Inicialmente com uma abordagem em termos energéticos e depois uma abordagem ao controlo da humidade e prevenção das condensações.

Gestão e Direção de Obra – Controlo de Prazos e Custos na Construção

O presente relatório de estágio, integrado na unidade curricular de DIPRE, para satisfação integral dos requisitos do grau de MESTRE EM ENGENHARIA CIVIL – ESPECIALIZAÇÃO EM GESTÃO DA CONSTRUÇÃO, aborda a temática de “Gestão e Direção de uma Obra”, explorando aspetos relativos ao controlo de prazos e de custos na construção, com o principal objetivo de prevenir e/ou mitigar os atrasos que, seja pela atual situação económico-financeira do país, seja pela falta de experiência dos intervenientes, continuam a existir. Aborda também, um conjunto de atividades realizadas na reabilitação dos Edifícios de Vila d��� Este – Fase II, destacando-se a aplicação do sistema ETICS (External Thermal Insulation Composite Systems), formulando e comparando rendimentos de aplicação entre equipas. Este estudo foi elaborado, não só para gerir da melhor maneira possível a aplicação do sistema em obra (reduzindo custos e prazos, sem afetar o modo de colocação do mesmo), mas também para servir de auxílio noutra obra com características semelhantes.