Browsing by Author "Costa, Luis"
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- Assessing the use of harvested greenhouse runoff for managed aquifer recharge to improve groundwater status in South PortugalPublication . Costa, Luis; P. Monteiro, J.; Hugman, Rui TwohigConcentration of nitrates in groundwater at the Nitrate Vulnerable zone of Faro, south Portugal, reaches values as high as 300 mg/l; therefore, according to the EU Water Framework Directive, mitigation measures need to be implemented. A Managed Aquifer Recharge scheme is proposed to accelerate the dilution and natural discharge of nitrates from the system. Source water availability is estimated from rainfall intercepted at existing greenhouses. Within the highest nitrate concentration area, estimated water availability for injection in existing wells is 1.50 hm(3)/year, a significant volume which represents approximately 15% of the aquifer direct recharge. It is proposed this is recharged to the aquifer through existing large-diameter traditional wells that are no longer used for abstraction. Injection test results suggest that the likely infiltration capacity of such wells is more than sufficient to allow collection of 95% of daily rainfall events. The effect of injecting this volume in the aquifer was estimated with the support of a 3D numerical groundwater flow and transport model. Results show considerable improvement in nitrate concentrations in the study area, in certain locations decreasing up to 70 mg/l by 2027. The model results predict a decrease in the number of nitrate threshold exceedances in observation points, from 33 to 30 by 2027 and 14 to 9 by 2040. It is likely that this measure may have a positive effect on other issues identified in the area, mostly related with quantity problems and seawater intrusion. Notwithstanding, issues including landowner support, clogging, conditions of greenhouses and wells, water quality, and climate change impacts will require further consideration to develop a successful and beneficial MAR scheme.
- Climatic and geologic controls on the piezometry of the Querença-Silves karst aquifer, Algarve (Portugal)Publication . Neves, Maria C.; Costa, Luis; Monteiro, José PauloKarst aquifers in semi-arid regions, like Queren double dagger a-Silves (Portugal), are particularly vulnerable to climate variability. For the first time in this region, the temporal structure of a groundwater-level time series (1985-2010) was explored using the continuous wavelet transform. The investigation focused on a set of four piezometers, two at each side of the S. Marcos-Quarteira fault, to demonstrate how each of the two sectors of the aquifer respond to climate-induced patterns. Singular spectral analysis applied to an extended set of piezometers enabled identification of several quasi-periodic modes of variability, with periods of 6.5, 4.3, 3.2 and 2.6 years, which can be explained by low-frequency climate patterns. The geologic forcing accounts for similar to 15 % of the differential variability between the eastern and western sectors of the aquifer. The western sector displays spatially homogenous piezometric variations, large memory effects and low-pass filtering characteristics, which are consistent with relatively large and uniform values of water storage capacity and transmissivity properties. In this sector, the 6.5-year mode of variability accounts for similar to 70 % of the total variance of the groundwater levels. The eastern sector shows larger spatial and temporal heterogeneity, is more reactive to short-term variations, and is less influenced by the low-frequency components related to climate patterns.
- Colapso cardiovascular pós-intubação orotraqueal emergentePublication . Eliseu, Afonso; Aguiar, André; Costa, Luis; Barreira, Bruno; Soares, Julio RicardoA intubação orotraqueal (IOT) é um procedimento indispensável na gestão emergente de doentes críticos, sendo que não está desprovida de complicações potencialmente graves. Este artigo pretende rever os fatores de risco associados à incidência e severidade destes efeitos adversos, bem como discutir que atuações podem beneficiar o doente crítico no momento da IOT.
- Drone-DEA: estará o futuro mais próximo?Publication . Aguiar, André; Eliseu, Afonso; Barreira, Bruno; Costa, LuisO primeiro estudo mundial sobre o papel dos drones na entrega de Desfibrilhador Automático Externo (DAE) no contexto de Paragem Cardiorrespiratória (PCR) em cenários reais foi realizado na Suécia e publicado em Agosto de 2021 na European Hearth Journal e apresentado no European Society of Cardiology Congress 2021.
- Estratégias de sedação em contexto pré-hospitalarPublication . Costa, Luis; Barreira, Bruno; Aguiar, André; Eliseu, Afonso; Gouveia, AlirioOs profissionais de saúde de Emergência Pré-Hospitalar são pioneiros no contacto com situações de emergência, onde uma elevada percentagem de doentes apresentasse com dor, agitação, ansiedade ou perda da patência da via aérea. Nestes casos, a sedação farmacológica é um instrumento inestimável no conforto, controlo e segurança dos mesmos. A literatura publicada sobre sedação em ambiente pré-hospitalar é reduzida, não existindo um consenso universal sobre as melhores estratégias farmacológicas para esse fim. Nesse sentido, o objetivo deste artigo é clarificar e expor de uma forma simples e sistematizada, as características e indicações dos principais agentes farmacológicos com utilidade em ambiente pré hospitalar. No final da leitura, espera-se que os profissionais de saúde se sintam confiantes na administração destes fármacos, ao mesmo tempo que garantem a segurança dos doentes pela escolha do melhor indutor para cada situação de emergência.
- Groundwater response to climate variability in Mediterranean type climate zones with comparisons of California (USA) and PortugalPublication . Malmgren, Katherine; Neves, Maria; Gurdak, Jason J.; Costa, Luis; Monteiro, JoséAquifers are a fundamental source of freshwater, yet they are particularly vulnerable in coastal regions with Mediterranean type climate, due to both climatic and anthropogenic pressures. This comparative study examines the interrelationships between ocean-atmosphere teleconnections, groundwater levels and precipitation in coastal aquifers of California (USA) and Portugal. Piezometric and climate indices (1989-2019) are analyzed using singular spectral analysis and wavelet transform methods. Singular spectral analysis identifies signals consistent with the six dominant climate patterns: the Pacific Decadal Oscillation (PDO), the El Nino-Southern Oscillation (ENSO), and the Pacific/North American Oscillation (PNA) in California, and the North Atlantic Oscillation (NAO), the Eastern Atlantic Oscillation (EA) and the Scandinavian Pattern (SCAND) in Portugal. Lower-frequency oscillations have a greater influence on hydrologic patterns, with PDO (52.75%) and NAO (46.25%) on average accounting for the largest amount of groundwater level variability. Wavelet coherences show nonstationary covariability between climate patterns and groundwater levels in distinct period bands: 4-8 years for PDO, 2-4 years for ENSO, 1-2 years for PNA, 5-8 years for NAO, 2-4 years for EA and 2-8 years for SCAND. Wavelet coherence patterns also show that coupled climate patterns (NAO+ EA- and paired PDO and ENSO phases) are associated with major drought periods in both the Mediterranean climate zones.
- In-channel managed aquifer recharge: a review of current development worldwide and future potential in EuropePublication . Standen, Kathleen; Costa, Luis; Monteiro, José PauloManaged aquifer recharge (MAR) schemes often employ in-channel modifications to capture flow from ephemeral streams, and increase recharge to the underlying aquifer. This review collates data from 79 recharge dams across the world and presents a reanalysis of their properties and success factors, with the intent of assessing the potential of applying these techniques in Europe. This review also presents a narrative review of sand storage dams, and other in-channel modifications, such as natural flood management measures, which contribute to the retardation of the flow of flood water and enhance recharge. The review concludes that in-channelMARsolutions can increase water availability and improve groundwater quality to solve problems a ecting aquifers in hydraulic connection with temporary streams in Europe, based on experiences in other parts of the world. Therefore, to meet the requirements of the Water Framework Directive (WFD), in-channel MAR can be considered as a measure to mitigate groundwater problems including saline intrusion, remediating groundwater deficits, or solving aquifer water quality issues.
- Modeling nitrate-contaminated groundwater discharge to the Ria Formosa Coastal Lagoon (Algarve, Portugal)Publication . Hugman, Rui; Stigter, Tibor; Costa, Luis; Monteiro, José PauloA numerical flow and transport model is developed to assess groundwater discharge and nutrient transport to the Ria Formosa coastal lagoon in southern Portugal. A total N load of 350 ton/year is estimated for the considered area, of which agriculture accounts for 73% of total N load, and domestic effluent and atmospheric deposition for the remaining 9% and 18% respectively. Model results suggest that nutrient recycling has led to the high concentrations observed in the Campina de Faro (M12) aquifer, but is still insufficient to account for observed values at the coastline. Furthermore results suggest that even for the best case mitigation scenario, good quality status will not be achieved by 2027, as mandated by the EU Water Framework Directive.
- Modeling students’ behavioral engagement through different in-class behavior stylesPublication . Gomes, Samuel; Costa, Luis; Martinho, Carlos; Dias, João; Xexéo, Geraldo; Moura Santos, AnaBackground The growing necessity of providing better education, notably through the development of Adaptive Learning Systems (ALSs), leveraged the study of several psychological constructs to accurately characterize learners. A concept extensively studied in education is engagement, a multidimensional construct encompassing behavioral expression and motivational backgrounds. This metric can be used to not only guide certain pedagogic methodologies, but also to endow systems with the right tutoring techniques. As such, this article aims to inspire improved teaching styles and automatic learning systems, by experimentally verifying the influence of in-class behaviors in students’ engagement. Results Over 16 math lessons, the occurrence of students’ and instructors’ behaviors, alongside students’ engagement estimates, were recorded using the COPUS observation protocol. After behavior-profiling the classes deploying such lessons, significant linear models were computed to relate the frequency of the students’ or instructors’ behaviors with the students’ engagement at different in-class periods. The models revealed a positive relation of students’ initial individual thinking and later group activity participation with their collective engagement, as well as a positive engagement relation with the later application of instructor’s strategies such as giving feedback and moving through class, guiding on-going work. Conclusions The results suggest the benefit of applying a workshop-like learning process, providing more individual explanations and feedback at the beginning of an interaction, leaving collective feedback and students’ guidance of on-going work for later on. Based on the relations suggested by our models, several guidelines for developing ALSs are proposed, and a practical illustrative example is formulated.
- Numerical modelling assessment of climate-change impacts and mitigation measures on the Querença-Silves coastal aquifer (Algarve, Portugal)Publication . Hugman, Rui; Stigter, Tibor; Costa, Luis; Monteiro, José PauloPredicted changes in climate will lead to seawater intrusion in the Querença-Silves (QS) coastal aquifer (south Portugal) during the coming century if the current waterresource-management strategy is maintained. As for much of the Mediterranean, average rainfall is predicted to decrease along with increasing seasonal and inter-annual variability and there is a need to understand how these changes will affect the sustainable use of groundwater resources. A densitycoupled flow and transport model of the QS was used to simulate an ensemble of climate, water-use and adaptation scenarios from 2010 to 2099 taking into account intra- and interannual variability in recharge and groundwater use. By considering several climate models, bias correction and recharge calculation methods, a degree of uncertainty was included. Changes in rainfall regimes will have an immediate effect on groundwater discharge; however, the effect on saltwater intrusion is attenuated by the freshwater–saltwater interfaces’ comparatively slow rate of movement. Comparing the effects of adaptation measures demonstrates that the extent of intrusion in the QS is controlled by the long-term water budget, as the effectiveness of both demand and supply oriented measures is proportional to the change in water budget, and that to maintain the current position, average groundwater discharge should be in the order of 50 × 106 m3 yr−1.