Partitioning of trace metals between soft tissues and shells of Patella aspera

This paper describes the partitioning of iron, manganese, zinc, copper, cadmium, cobalt, nickel and lead between the soft tissues and the shells of the gastropod mollusc Patella aspera. Specimens of the limpet P aspera were collected from a clean coastal marine site (CMS) and from an estuarine contaminated site (ECS) on the south coast of Portugal. Fe and Zn concentrations were significantly lower on both populations and less variable in the shells than in the soft tissues. In contrast Mn concentrations were higher in the shells than in the soft tissues at ECS. The partitioning factor (PF), defined as the ratio between the mean metal concentrations in soft tissues and in the shells, was maximum for iron and minimum for manganese. Between the soft tissues and the shells, only manganese at ECS recorded a significant relationship between metal concentrations, suggesting that the mechanism that controls the accumulation of this essential metal in both tissues was different from the others. From the obtained data, in biomonitoring sewage contamination studies, shells of P. aspera can be considered as a good indicator for Mn while the soft tissues for Zn. As copper, cadmium, nickel and cobalt concentrations were much higher in the soft tissues than in the shells ( < 0.1 mug g(-1)), this indicates that the shells were not a good indicator for these metals because they do not reflect the environmental bioavailability as do the soft tissues.FRMH/BD/403/92info:eu-repo/semantics/publishedVersio

Minor and trace elements in the shell of Patella aspera (Röding 1798)

Specimens of the limpet Patella aspera were collected from a clean, coastal marine site and a contaminated estuary on the south coast of Portugal. The shells were analysed individually for their minor (Mg, Sr) and trace element (Fe, Mn, Zn) content. Mean concentrations of these elements in the shell of P. aspera were 4651, 1318, 35.8, 29.9 and 5.5 μg g−1, respectively. The elemental concentrations exhibited both a marked intra- and inter-population variability. Despite the variability within individual populations, significant differences in the trace element composition were apparent between the shells taken from the two sites. Small shells (<2 g) provided the best resolution between sites for both manganese and iron. Differences in zinc were best resolved for larger shells. The shell of P. aspera has an extraordinarily high magnesium concentration, which is insensitive to gross salinity differences, and a trace metal assemblage that can be interpreted in terms of environmental exposure. On these grounds, it is recommended that the shell of P. aspera is a tissue for potential use in environmental trace metal monitoring.FRMH/BD/403/92info:eu-repo/semantics/publishedVersio

Metals in the shell of Bathymodiolus azoricus from a hydrothermal vent site on the Mid-Atlantic Ridge

Specimens of the mussel Bathymodiolus azoricus were collected from Menez Gwen, a relatively shallow (850 m) hydrothermal vent field on the Mid-Atlantic Ridge. Each bivalve shell (n = 21) was individually cleaned by selective chemical. The residual crystal matrix of each shell was individually analysed for the concentrations of the minor elements magnesium and strontium and the trace elements iron, manganese, copper and zinc. The chemical composition of the crystal matrix is unusual. B. azoricus is identified as a species having one of the most strontium impoverished shells amongst the marine molluscs. For a bimineral species the magnesium concentration is also extraordinary low. Despite originating from a trace metal rich environment; the metal concentrations in the shells were exceptionally low. Mean concentrations of iron, manganese, copper and zinc were 20.6, 3.7, 0.6 and 9.4 microg g(-1) respectively. Minor and trace element concentrations exhibited a marked intra-population variability. Copper concentrations increased and iron and zinc concentrations decreased with increasing shell weight. Due to its insensitivity to the high environmental levels of trace elements and the variability in intra-population concentrations induced by shell weight the crystal matrix of the shell of B. azoricus has little potential for use in environmental trace metal monitoring in areas contiguous to deep-sea hydrothermal vents.info:eu-repo/semantics/publishedVersio

SPlanner : uma aplicação gráfica de definição flexível de jogadas estudadas no RoboCup

Tese de mestrado integrado. Engenharia Informática e Computação. Universidade do Porto. Faculdade de Engenharia. 201

As PPP e os processos tradicionais de contratação pura: vantagens e desvantagens

Mestrado em Engenharia Civil – ramo Tecnologia e Gestão das ConstruçõesNeste trabalho foi desenvolvido um estudo de dois modelos usados na contratação pública para a execução de um bem ou serviço de utilidade pública. Relativamente às PPP são analisadas de forma a obter respostas a experiências do passado e parâmetros que possam ser melhorados de forma a obter um maior aproveitamento no futuro. Contrapõem-se aqui a “contratação pública tradicional” envolvendo a contratação da construção de uma determinada infraestrutura que será posteriormente explorada pelo próprio Estado, comprometendo-se diretamente com a responsabilidade na prestação do serviço. Na contratação pública em regime de parceria público privada, o Estado têm o papel de regulador do serviço público, isto é, o setor público opta por contratar um serviço a longo prazo, transferindo para o setor privado a responsabilidade de construção e posterior gestão conforme o vínculo previamente definido. Este modelo de cooperação entre as duas partes proporciona adquirir uma forma de gestão incorporando a noção do ciclo de vida do projeto, resultando em benefícios económicos e inovações com interesse para os utilizadores. As parcerias público privadas destacam-se atualmente como um modelo que está a ser alvo de grande debate e controvérsia, como tal neste trabalho é analisado os dois modelos de contratação pública procurando fomentar algumas das mais-valias e desvantagens na procura de avaliar erros ou pontos de melhoria de processos efetuados regularmente.This work comprises a study of two models used in public procurement for the implementation of a common good or public service. As for the PPP, they are analyzed in order to obtain answers for past experiments and parameters that can be improved in order to obtain better use in the future. There is a contrast here with “traditional procurement contracts” involving the construction of a designated infrastructure which will later be exploited by the state, who will take full responsibility for providing the service. In public procurement under the public private partnership, the state plays a role in regulating the public service, that is, the public sector chooses to hire a long-term service, transferring to the private sector the responsibility for construction and subsequent management according to the previously defined contract. This model of cooperation between the two parties provides the opportunity of a certain type of management which includes the concept of the project´s life cycle, resulting in economic benefits and innovations of interest to users. The public-private partnerships stand out today as a model that is the target of much debate and controversy, so this work analyzes the two models of procurement, thereby seeking to promote some of the gains and disadvantages with a view to evaluating errors or points of improvement in processes carried out regularly

Proposta e implementação de melhorias num armazém intermédio

Mestrado em Engenharia e Gestão IndustrialCom a elaboração deste projecto pretendeu-se evidenciar a importância de uma boa gestão num armazém de embalagens. Depois de delineado o plano e os objectivos a atingir, procurou-se compreender o processo de encomenda da organização, indispensável para basear a proposta de layout apresentada à direcção logística. Após implementada a nova solução, foram medidos tempos de picking para organização das referências no novo armazém.The aim of this project is to point out the importance of good management in a package warehouse. After the design of the planning and the statement of the objectives, we tried to understand the ordering process of the organization, indispensable to base the proposal of layout presented to the logistics direction. After the implementation of the new solution, picking times were measured to organize the references in the new warehouse

Uma casa de férias na Galé: apontamentos sobre um processo de projecto

Este trabalho, apresentado sob o título "Uma casa de férias naGalé: Apontamentos sobre um processo de projeto", procura explicaruma metodologia projetual, não como um processo sistemático, masantes como um processo intelectual e intuitivo.Através da realização de um projeto de arquitetura para uma casade férias para um cliente concreto, procura-se expor as circunstânciase o processo criativo em causa, aproveitando a oportunidade de, numcontexto académico, fazer uma aproximação a uma situação real.Assim, pretende-se dar a conhecer um pouco melhor assituações e relações que advêm de um cruzamento entre as vontades dorequerente, o lugar, os impulsos e as motivações pessoais, assim comocondicionantes de várias naturezas que foram surgindo ao longo dodesenvolvimento da proposta e do trabalho, expondo momentos chavepara a sua compreensão.This work, presented under the title "A holiday home in Galé:Notes on a project process," seeks to explain one architectural designmethodology, not as a systematic process, but rather as an intellectualand intuitive process.By conducting an architectural design for a holiday home to aspecific client, this work seeks to expose the circumstances of the creativeprocess involved, taking the opportunity of an academic context,making an approach to a real situation.Thus, it is intended to present the situations and relations thatcome from the confrontation between the wishes of the applicant, theplace, the impulses and personal motivations, and constraints of variouskinds that may emerge throughout the development of the proposal andthe work, exposing key moments for its understanding

Patterns and predictors of phytoplankton assemblage structure in a Coastal Lagoon: Species-specific analysis needed to disentangle anthropogenic pressures from ocean processes

Phytoplankton are dominant primary producers and key indicators in aquatic ecosystems. Understanding the controlling factors on the structure of phytoplankton assemblages is fundamental, but particularly challenging at the land–ocean interface. To identify the patterns and predictors of phytoplankton assemblage structure in the Ria Formosa coastal lagoon (south Portugal), this study combined phytoplankton abundance along a transect between the discharge point of a wastewater treatment plant and a lagoon inlet, over two years, with physico-chemical, hydrographic, and meteo-oceanographic variables. Our study identified 147 operational taxonomic units (OTUs), and planktonic diatoms (60–74%) and cryptophyceans (17–25%) dominated the phytoplankton in terms of abundance. Despite strong lagoon hydrodynamics, and the lack of spatial differences in the phytoplankton abundance and most diversity metrics, the multivariate analysis revealed differences in the assemblage structure between stations (p < 0.001) and seasons (p < 0.01). Indicator analysis identified cryptophyceans as lagoon generalists, and 11 station-specific specialist OTUs, including Kryptoperidinium foliaceum and Oscillatoriales (innermost stations) and potentially toxigenic species (Pseudo-nitzschia and Dinophysis; outer lagoon station, p < 0.05). Water temperature, pH, and nutrients emerged as the variables that best explained the changes in the phytoplankton assemblage structure (p < 0.001). Our findings provide insight into the relevance of local anthropogenic and natural forcings on the phytoplankton assemblage structure and can be used to support the management of RF and other coastal lagoons.MAR-01.04.02-FEAMP-0003info:eu-repo/semantics/publishedVersio

Concentraciones de nutrientes en aguas costeras: impacto del Río Guadiana

Water samples were collected over an area of 900 km(2) adjacent to the outflow of the Guadiana River in January 1999 to characterize the concentrations and spatial distribution of nutrients (ammonium, nitrite, nitrate, phosphate and silicate) in the water column. The purpose of the study was to characterize a winter situation of low discharge in terms of nutrient concentrations in the coastal area adjacent to the Guadiana outflow, before the reduction of the river flow due to the completion of the Alqueva Dam. The results show that the maximum influence of the Guadiana outflow was close to the mouth of the Guadiana River, where the highest nutrient concentrations and the minimum of salinity were registered. At the surface, the nutrient concentrations decreased gradually as the distance from the coast increased. The influence of the Guadiana outflow at the surface, despite being small, was evident in the area of about 90 km(2) that extends westwards from the mouth of the river. In this area, the increase in N compounds was more significant than in P and Si. The vertical influence of the outflow of the Guadiana River, until over the isobath lower than 30 m, was reflected in nutrient concentrations that decreased with the increase in depth. However, when the depth of the water column was greater than 30 m, the nutrient concentrations increased with the increase in depth. It is expected that with the completion of the Alqueva Dam, the outflow of the Guadiana River will be reduced even further. Nutrient concentrations will also be reduced and the influence of the river in the coastal zone will be even smaller. This could have a negative impact on the nutrient biogeochemical cycles and on the overall productivity of the area.En un área de 900 km2 alrededor de la desembocadura del Río Guadiana se recolectaron muestras de agua para caracterizar las concentraciones y distribución espacial de nutrientes (amonio, nitritos, nitratos, fosfatos y silicatos) en la columna de agua. El propósito de este estudio fue caracterizar la condición invernal de pocas descargas, en términos de concentración de nutrientes en el área costera adyacente a la desembocadura del Guadiana, antes de que el flujo del río se vea reducido por la conclusión de la Presa Alqueva. Los resultados indican que la mayor influencia de la descarga del Guadiana se observó cerca de la boca del río, donde se registraron las mayores concentraciones de nutrientes y la salinidad más baja. En superficie, las concentraciones de nutrientes disminuyeron gradualmente con el aumento de la distancia a la costa. La influencia de la descarga del Guadiana en superficie, aunque pequeña, fue evidente en el área de ~90 km2 que se extiende de la boca del río hacia el oeste. En esta área el incremento de compuestos de N fue más significativo que el de los de P y Si. La influencia vertical de la descarga del Río Guadiana, hasta por encima de la isóbata < 30 m se reflejó en las concentraciones de nutrientes que disminuyeron conforme aumentaba la profundidad. Sin embargo, cuando la profundidad de la columna de agua era > 30 m las concentraciones de nutrientes aumentaron con la profundidad. Es de esperar que con la terminación de la Presa Alqueva la descarga del río se vea aún más disminuida. Las concentraciones también se verán reducidas y la influencia del río en la zona costera será aún menor. Esto podría tener un impacto negativo en los ciclos biogeoquímicos de nutrientes y en la productividad global del área.proyecto SIRIA, financiado conjuntamente entre el Ministerio de Defensa y la Fundación de las Universidades de Portugal, en el marco del Programa Medio Ambiente y Defensainfo:eu-repo/semantics/publishedVersio

Dosimetric evaluation in breast tumours: comparison of three techniques

Objetivo – Comparar a técnica convencional, a técnica de energias mistas e a técnica field-in-field com energias mistas, verificando a dose recebida nos órgãos de risco e no volume alvo. Metodologia – Quinze doentes com carcinoma da mama esquerda classificadas de T1-T3N0M0 foram tratadas com cirurgia conservadora da mama, seguida de radioterapia pós-operatória. Para cada doente realizaram-se 3 planeamentos dosimétricos, sendo que cada um deles diz respeito a uma das diferentes técnicas em estudo. Através dos HDV gerados avaliaram-se a Dmáx, Dmed, Dmín, D95%, D3% e a homogeneidade da dose no volume alvo, bem como a dose nos órgãos de risco. Utilizou-se o teste de Friedman para verificar a significância do estudo, com um intervalo de confiança de 95%. Resultados – Relativamente ao pulmão esquerdo e ao coração obtiveram-se, com a técnica field-in-field com energias mistas, doses inferiores em comparação com as outras duas técnicas. Para a Dmáx e a homogeneidade de dose no PTV, a técnica field-in-field com energias mistas revelou-se mais eficaz, comparativamente às outras técnicas. No entanto, verificou-se uma melhor cobertura de dose no PTV com a técnica convencional. Considerações finais – A técnica field-in-field com energias mistas permite uma redução da dose nos órgãos de risco, uma redução significativa da Dmáx no PTV e melhora a homogeneidade da dose, comparativamente com as outras técnicas. Os resultados obtidos com a técnica field-in-field com energias mistas apontam para a redução dos efeitos secundários provocados pelo tratamento. ABSTRACT - Purpose – To compare the conventional technique, the technique of mixed energies and the technique field-in-field with mixed energies, checking the received dose in organs at risk and target volume. Methods – Fifteen patients with carcinoma of the left breast classified as T1-T3N0M0 were treated with breast-conserving surgery, followed by postoperative radiotherapy. For each patient were carried out three dosimetric plannings, each one of them concerns the different techniques under study. Through the DVH generated to evaluate Dmax, Dmed, Dmin, D95%, D3% and the homogeneity of the target volume dose, well as the dose in organs at risk. We used the Friedman test to assess the significance of the study, with a confidence interval of 95%. Results – For the left lung and heart were obtained with the technique field-in-field with mixed energies, lower doses compared with the other two techniques. For the Dmax and the homogeneity of the PTV dose, the technique field-in-field with mixed energies was more effective compared to other techniques. However, there was a better coverage of the PTV dose with conventional technique. Conclusions – The technique field-in-field with mixed energy allows a reduction in dose for organs at risk, a significant reduction Dmax in PTV and improves the homogeneity of the dose compared with other techniques. The results obtained with the technique field-in-field with mixed energy indicate to reduce the side effects caused by the treatment