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- Role of subaerial volcanic rocks and mantle plumes in creation of South Atlantic margins: implications for salt tectonics and source rocksPublication . Jackson, M. P. A.; Cramez, Carlos; Fonck, Jean-MichelSeaward-dipping re¯ectors (SDRs) represent ¯ood basalts rapidly extruded during either rifting or initially subaerial sea-¯oor spreading. Evaporites can form on this basaltic proto-oceanic crust, as in the Afar Triangle today. Evidence for SDRs in South Atlantic deep-water regions comes from proximity to the uniquely large Paranaà ±Etendeka volcanic province onshore, the Tristan and Gough hot spots, drilled volcanic rocks, and seismic pro®les showing SDR provinces more than 100 km wide, as much as 7 km thick, and thousands of kilometers long. SDRs are clearest adjoining the Aptian salt basins. However, we speculate that SDRs are also present but seismically obscured below the salt basins. We argue that the conjugate Aptian salt basins are post-breakup, not pre-breakup; they were separated from the start by a mid-oceanic ridge; distal salt accumulated on proto-oceanic crust, not rift basins. This hypothesis is supported by: seismic stratigraphy and structure; magnetic anomalies; plate reconstructions; and hydrothermal potash evaporites. An important implication for exploration is that thick basalts, rather than rift-age source rocks, may underlie distal parts of the salt basins.
- Impact of road traffic emissions on air quality of the Lisbon regionPublication . Borrego, C.; Tchepel, O.; Barros, Nelson; Miranda, A.I.The main purpose of this paper is to present the study of traffic emissions impact on the Lisbon region air quality. Two approaches of emission data generation with high spatial and temporal resolution are presented and compared. Main roads were processed as line sources and hot on-road emissions were calculated based on daily mean traffic and emission factors distinguished for several road classes and vehicle types. Also, the disaggregation of national CORINAIR inventory has been performed on the basis of statistical information of fuel consumption and population density. The comparison of emission data obtained by these two approaches demonstrates a good agreement for total values, but a significant difference for spatial distribution of the data. To ensure completeness of the data, to improve their spatial resolution and also to analyse the impact of the traffic emissions, a combination of the two approaches was applied to generate the emission data used by a photochemical numerical system to simulate the atmospheric circulation and the air pollution pattern in Lisbon under summer meteorological conditions, having different emission scenarios. It was possible to conclude that an air pollution abatement strategy is urgently needed and it should take into account the strong contribution of road traffic emissions to the Lisbon air pollution levels.
- Apego à família, grupo de pares e condutas anti-sociais na adolescência: um estudo exploratório realizado na Escola Secundária António Nobre em Vila Nova de GaiaPublication . Curto, Paulo Jorge de Jesus; Martins, José SoaresApoiado nas teorias dos processos de socialização, o presente trabalho estuda a influência dos contextos de socialização, família e pares, na génese das condutas anti-sociais dos adolescentes.( Usando uma amostra de 100 indivíduos. Verificou-se que os pressupostos da Teoria do Controlo Social de Hirschi e da Teoria da Associação Diferencial de Sutherland foram, no essencial, comprovados pelos resultados deste estudo. No entanto, as correlações observadas indicam que, de facto, o grupo de pares é a principal fonte de influência no comportamento (delinquente) dos jovens. Enquanto, o apego à família revela fracas correlações com as condutas anti-sociais dos jovens observados. Mesmo assim, apesar dos resultados obtidos apontarem o grupo de pares (associação a pares desviados) como o preditor mais poderoso da delinquência individual, os mesmos resultados sugerem que o apego à família pode ser um factor importante na sua determinação.
- Importance of handling organic atmospheric pollutants for assessing air qualityPublication . Borrego, C.; Gomes, P.; Barros, Nelson; Miranda, A.I.Volatile organic compounds (VOCs) are the main precursors of tropospheric ozone production, playing an important role in photochemical pollution of the atmosphere and, consequently, in the degradation of air quality. Air quality photochemical models require a specific VOC profile for each different main source, based on the most important group compounds. Chromatographic techniques have been used to identify and measure VOC in Portugal. These measured values were used to simulate photochemical pollution, and modelling results were compared with those from another simulation using VOC class distributions from the literature. Ozone concentration values estimated via both simulations indicate the importance of using VOC data from Portugal instead of those obtained in different conditions.
- Abordagem ambiental na empresa: perspectivas de gestão e contabilidadePublication . Silva, Carla Alexandra Faria; Guimarães, Raul
- Phenolic acids and derivatives: studies on the relationship among structure, radical scavenging activity, and physicochemical parametersPublication . Silva, Francisco A. M.; Borges, Fernanda; Guimarães, Carla; Lima, José L. F. C.; Matos, Carla; Reis, SaletteThe antiradical activity of caffeic acid (1), dihydrocaffeic acid (5), and their corresponding n-alkyl esters was evaluated by using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) method. Dihydrocaffeic acid (5) was the most potent compound, having an antiradical effect higher than that of (+/-)-alpha-tocopherol, whereas caffeic acid (1) was less efficient. Esterification of the carboxyl group of dihydrocaffeic acid (5) had a dramatic effect on its antiradical potency, but similar effects were not observed for caffeic acid (1) derivatives. The n-alkyl esters of both phenolic series had similar potencies, and their antiradical activities were independent of the alkyl chain length. Dose-dependent scavenger effects were found in both series. Acid-base properties of the compounds, evaluated by using potentiometry and spectrophotometry, showed that the catechol moiety had pK(a2) and pK(a3) values of 9. 24-9.02 and 11.38-10.99 in the dihydrocaffeic series and 8.48-8.24 and 11.38-11.07 in the caffeic series, respectively. Antiradical activity and pK(a) values of the compounds were not related.
- Violência e suporte familiar, auto-conceito e delinquência na adolescência: estudo exploratório numa amostra de adolescentes do ensino secundárioPublication . Cruz, Ana Sofia Matias Rodrigues da; Martins, José SoaresCom o presente estudo procurou-se determinar as relações existentes entre a violência e o suporte familiar, o auto-conceito e a delinquência na adolescência. Para tal foram utilizados três instrumentos: o Inventário Clínico de Auto-Conceito (ICAC), de Adriano Vaz Serra, o Questionário de Condutas Anti-Sociais de Lourdes Mirón e três sub-escalas do «Exposure to Abusive and Supportive Environments Parenting Inventory» (EASE-PI), de Karen Nicholas e Stephen Bieber. Os questionários foram aplicados a uma amostra composta por alunos do 9º ano, 10º, 11º e 12º anos da Escola Secundária Filipa de Vilhena. Constituem-se como palavras-chave para este estudo auto-conceito, abuso emocional, abuso físico, suporte familiar e comportamento anti-social. Dos resultados desta investigação conclui-se a existência de correlações significativas entre os comportamentos sociais, a violência e o suporte familiar e algumas das dime4nsões do auto-conceito.
- Analysis of the deep chlorophyll maximum across the Azores FrontPublication . Macedo, M.F.; Duarte, Pedro; Ferreira, João; Alves, M.; Costa, V.Physical, chemical and biological observations made in late July and August 1997 across the Azores Front (37ºN, 32ºW to 32ºN, 29ºW) are presented. The objectives of the study were: (1) to analyse horizontal and vertical profiles of temperature, salinity, density, nutrients and chlorophyll-a (Chl a) of the top 350 m; (2) to identify the main differences in the deep Chl a Maximum (DCM) and hydrographic structure between the water masses that pass north and south of the Azores Front; and (3) to estimate phytoplankton primary production in these water masses. Horizontal and vertical profiles of salinity, temperature, density, nutrients and phytoplankton pigments in the top 350 m were analysed. The Front separates two distinct water types: the 18 ºC ModeWater (18MW) of subtropical origin, and the 15 ºC ModeWater (15MW) of sub-polar origin. Differences in the DCM and hydrographic structure between 18 MW and 15 MW were observed in the contour plots of each section. The average Chl a concentration between 5 and 200 m depth decreased significantly from 15 MW to 18 MW. The same pattern was observed for the Chl a concentration at the DCM depth. A vertical one-dimensional model was used to estimate the phytoplankton primary production in the 15 MW and 18 MW and led to an estimated water column average gross primary productivity (GPP) between 1.08 and 2.71 mg C m
- Superposed deformation straddling the continental-oceanic transition in deep-water AngolaPublication . Cramez, Carlos; Jackson, M. P. A.The Angolan margin is the type area for raft tectonics. New seismic data reveal the contractional buffer for this thin-skinned extension. A 200-km-long composite section from the Lower Congo Basin and Kwanza Basin illustrates a complex history of superposed deformation caused by: (1) progradation of the margin; and (2) episodic Tertiary epeirogenic uplift. Late Cretaceous tectonics was driven by a gentle slope created by thermal subsidence; extensional rafting took place updip, contractional thrusting and buckling downdip; some distal folds were possibly unroofed to form massive salt walls. Oligocene deformation was triggered by gentle kinking of the Atlantic Hinge Zone as the shelf and coastal plain rose by 2 or 3 km; relative uplift stripped Paleogene cover off the shelf, provided space for Miocene progradation, and steepened the continental slope, triggering more extension and buckling. In the Neogene, a subsalt half graben was inverted or reactivated, creating keystone faults that may have controlled the Congo Canyon; a thrust duplex of seaward-displaced salt jacked up the former abyssal plain, creating a plateau of salt 3–4 km thick on the present lower slope. The Angola Escarpment may be the toe of the Angola thrust nappe, in which a largely Cretaceous roof of gently buckled strata, was transported seawards above the thickened salt by up to ,20 km. q 2001 Elsevier Science Ltd. All rights reserved.
- A prevenção primária do consumo de drogas na adolescênciaPublication . Topa, Nancy Maria Ferreira Vieira; Martins, José SoaresO presente trabalho monográfico, incide sobre o estudo da prevenção primária do consumo de drogas na adolescência. Este trabalho é constituído por uma parte de cariz teórico, na qual são referidos os principais aspectos relativos ao consumo de drogas na adolescência e à prevenção primária, enquanto estratégia de combate ao uso destas substâncias psicoactivas. Relativamente à parte empírica desta monografia, pretende-se estudar as relações existentes entre as actividades de lazer e o consumo (ou não consumo) de drogas na adolescência e, ainda, avaliar o grau de consumo de drogas e as diferenças significativas em função do género e da idade. Dos resultados, conclui-se que determinadas actividades de lazer são inibidoras/preventivas do consumo de drogas, enquanto que outras estão associadas a um maior uso destas substâncias. Para além disto, conclui-se, por um lado, que não existem diferenças significativas entre os géneros, no que respeita ao consumo de drogas (com excepção da heroína cujo consumo é significativamente superior nos rapazes) e, por outro lado, que existe um aumento de consumo de drogas com a idade (com excepção do consumo de inalantes, embora a diferença não seja significativa).