Browsing by Author "Ferreira, A."
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- Biomarkers: a strategic tool in the assessment of environmental quality of coastal watersPublication . Picado, Ana; Bebianno, Maria João; Costa, M. H.; Ferreira, A.; Vale, C.Ecosystems are under the pressure of complex mixtures of contaminants whose effects are not always simple to assess. Biomarkers, acting as early warning signals of the presence of potentially toxic xenobiotics, are useful tools for assessing either exposure to, or the effects of these compounds providing information about the toxicant bioavailability. In fact, it has been argued that a full understanding of ecotoxicological processes must consider an integrated multi-level approach, in which molecular impact is related with higher-order biological consequences at the individual, population and community levels. Monitoring programs should make use of this tool to link contaminants and ecological responses fulfilling strategies like those launched by OSPAR (Commissions of Oslo and Paris) Convention on the protection of the marine environment of the North-East Atlantic and the International Council for the Exploration of the Sea (ICES). An overview of the work done in the past few years using biomarkers as in situ tools for pollution assessment in Portuguese coastal waters is presented as a contribution to the set up of a biomonitoring program for the Portuguese coastal zone. Considering the data set available the biomonitoring proposal should include the analysis of biomarkers and effects at individual levels. The aim of the program will include a spatial and temporal characterization of the biomarkers acetyl-cholinesterase, metallothioneins, DNA damage, adenylate energy charge and scope-for-growth levels. The investigation of the spatial variation of biomarkers is crucial to define sites for long term monitoring, which will be integrated with a chemical monitoring program. This framework will be a major contribution to the implementation of a national database for the use of biomarkers along the Portuguese coast.
- Conceptual and quantitative categorization of wave-induced flooding impacts for pedestrians and assets in urban beachesPublication . Garzon, Juan L.; Ferreira, Ó.; Reis, M. T.; Ferreira, A.; Fortes, C. J. E. M.; Zózimo, A. C.Coastal fooding is a major threat to communities living in low-lying areas and the increase in the anthropogenic pressure in coastal zones and the efects of climate change (e.g., sea-level rise, increase in storminess and its frequency) are promoting an enhancement of the existing risks for population and properties 1–4 . Coastal fooding results from the interaction of oceanic and atmospheric processes with the local and regional features (topography, nearshore bathymetry, continental shelf, and land use). Among the diferent oceanic agents that might drive coastal fooding, wave-related processes have been found to be the dominant component in large areas of the globe compared to storm surges and tides 5 . When waves approach the shoreline, a large part of the wave energy is dissipated across the surf zone by wave breaking. However, a portion of the remaining energy is converted to potential energy in the form of wave runup on the beach foreshore 6 contributing to boosting the extreme water levels 3 . When the existing natural or man-made coastal protection structure (constructed on land) is lower than the maximum level that water can reach by wave attack, a discharge occurs over the structure and propagates inland. It can be called green water 7 (non-impulsive), when a layer of water passes over the crest, or white water 7 (or impulsive conditions) when waves break on the seaward face of the structure and produce signifcant volumes of splash or spray (not considered here). Terefore, wave runup (and overtopping) is important to coastal planners and engineers because it delivers much of the energy responsible for causing a fooding event 8. Besides disruptions in local services and transportation, during such events, seawater can travel with high velocities, which in turn can afect the integrity of urban elements and properties, and severely injure people.
- Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio are not predictive of pathologic complete response to neoadjuvant chemotherapy in triple-negative breast cancerPublication . Pinho, I. Soares de; Barroso, T.; Trabulo, C.; Campoa, E.; Patel, V.; Gonçalves, L.; Araújo, J.; Monteiro, C.; Ferreira, A.; Machado, B.; Dâmaso, S.; Luz, P.; Sousa, R. Teixeira de; Costa, L.Pathological complete response (pCR) to neoadjuvant chemotherapy (NAChT) has been validated as a predictor of long-term survival in breast cancer (BC), especially in triple-negative breast cancer (TNBC)
- Phytoplankton response to nutrient pulses in an upwelling system assessed through a microcosm experiment (Algarrobo Bay, Chile)Publication . Ferreira, A.; Sa, Carolina; Silva, N.; Beltran, C.; Dias, A. M.; Brito, A. C.Nutrient enrichment in coastal areas can lead to severe disturbances in marine ecosystems with implications on ecosystem functioning. The primary goal of this study was to understand the response of phytoplankton, from a region with intense upwelling events, to pulsed nutrient enrichments. A microcosm experiment using natural assemblages was conducted, following the addition of inorganic nitrogen (N) and phosphorus (P) and considering two different nutrient limitation conditions (N:P<16 and N:P>16). Laboratory work included the analysis of nutrients, as well as phytoplankton cell abundances. A fast response to the pulsed nutrient enrichments were observed in both treatments as biomass increased. Although higher biomass values were found under higher N concentrations, the community's composition was similar in both treatments. Centric diatoms, particularly Chaetoceros spp., strengthened their dominance, suggesting that, under these conditions, these may have physiological advantages that promote their growth over other groups. Throughout the experiment, phytoflagellates and pennate diatoms were common, while dinoflagellates were scarce. This study contributes to understanding how phytoplankton communities' growth and composition relate to nutrient pulses. These results provide relevant data for environmental quality assessment and management of marine environments.