Artigos de Revista

Pressurized powdered activated carbon/coagulation/ceramicmicrofiltration (PAC/Alum/MF) was investigated at pilot scale for treating low turbidity and low natural organic matter (NOM) surface waters spiked with organic microcontaminants.

Wastewater treatment plants (WWTPs) are significant reservoirs of bacterial resistance. This work aims to identify the determinants of resistance produced by Gram-negative bacteria in the influent and effluent of two WWTPs in Portugal. A total of 96 wastewater samples were obtained between 2016 and 2019. The numbers of total aerobic and fecal contamination bacteria were evaluated, and genomic features were searched by polymerase chain reaction (PCR) and Next-Generation Sequencing (NGS). Enterobacteriaceae corresponded to 78.6% (n = 161) of the 205 isolates identified by 16sRNA. The most frequent isolates were Escherichia spp. (57.1%, n = 117), followed by Aeromonas spp. (16.1%, n = 33) and Klebsiella spp. (12.7%, n = 26). The remaining 29 isolates (14.1%) were distributed across 10 different genera. Among the 183 resistant genes de-tected, 54 isolates produced extended spectrum ?-lactamases (ESBL), of which blaCTX-M-15 was pre-dominant (37 isolates; 68.5%). A KPC-3 carbapenemase-producing K. oxytoca was identified (n = 1), with blaKPC-3 included in a transposon Tn4401 isoform b. A higher number of virulence genes (VG) (19 genes) was found in the E. coli 5301 (O25b-ST131-B2) isolate compared with a commensal E. coli 5281 (O25b-ST410-A) (six genes). Both shared five VG [Enterobactin; Aerobactin, CFA/1 (clade ?); Type1 (clade ?1); Type IV]. In conclusion, this work highlights the role of relevant clinical bacteria in WWTPs, such as KPC-3-producing K. oxytoca, and, for the first time, a CTX-M-15-producing Ochromobactrum intermedium, a human opportunistic pathogen, and a SED-1-producing Citrobacter farmeri, an uncommon CTX-M-type extended-spectrum be-ta-lactamase.

É cada vez mais usual o recurso à modelação numérica para a simulação de eventos de galgamento, inundação e erosão em zonas costeiras. Neste estudo, recorre-se ao acoplamento de dois modelos, SWAN + XBeach (modo surf beat), para a propagação da agitação marítima do largo até à zona de espraio e para reproduzir a evolução morfodinâmica, a fim de avaliar a ocorrência de galgamento e erosão resultantes de eventos meteo-oceanográficos extremos. O local de estudo incide sobre o sector urbano artificializado da Costa da Caparica, que é composto por um campo de esporões e uma estrutura de proteção aderente em toda a extensão, formando seis células de praia arenosa. As simulações cobriram 96 h de forçamentos oceanográficos, representando, assim, a passagem da tempestade Hércules/Christine, entre os dias 3 e 7 de janeiro de 2014. O modelo SWAN propagou com sucesso as condições de agitação marítima para a área de estudo, quando comparado com os dados registados pela boia do Porto de Lisboa. Em relação ao modelo XBeach, este foi capaz de reproduzir alguma da evolução morfodinâmica espectável, contudo a erosão da praia emersa ficou aquém dos relatos documentados, não tendo sido possível avaliar quantitativamente os resultados. O alcance máximo do espraio obtido ao longo deste troço de costa foi inferior ao documentado, o que induz a falhas na previsão de inundações devido ao galgamento. Estes resultados podem ser devidos a uma parametrização inadequada do modelo e/ou à falta de levantamentos topo-batimétricos da praia. Esta abordagem metodológica representa um passo importante para uma melhor estimativa da evolução morfodinâmica na Costa da Caparica devido a eventos de tempestade e significa um importante esforço inicial para melhorar a avaliação dos eventos de galgamento e inundação.

In this paper, the authors discuss the use of public spaces by teenagers in four public parks in Lisbon, as as part of the larger research project under the auspices of the European Union. Using the living labs methodology, the study centered on teenagers as potential co-creators of public spaces through their social and spatial practices, and considers their potential for civic involvement and place making.

The correct calculation of forces and moments caused by wave action over crown wall structures is critical for their design. There are several existing equations for this, some of which are sanctioned in practice as it is the case for Jensen (1984) and Bradbury et al. (1998), Günback and Gökce (1984), Martin et al. (1999), Berenguer and Baonza (2006), and Pedersen (1996) and Nørgaard et al. (2013). These equations are the main tool for the design of breakwater crown walls and their accuracy is crucial to ensure the stability of the crown wall, especially when considering the sea level rise due to climate change and the possible damage of the armor, since both aspects are not usually considered in most original design studies. In a scenario of climate change, it is very important to estimate the possible changes in security factors due to both these aspects, comparing the results with the original design ones. This paper has as main objective to analyze it for the case study of Ericeira rubble mound breakwater in Portugal. For this, a comparison of the results using those equations and different scenarios including the current, considering sea level rise and armor damage, were performed to extract some conclusions: the increase in the sea level in the case study was not significant and therefore its incidence is very small; and the damage to the main armor by losing pieces at the berm is much more important in this case study, so it is essential to carry out the proper maintenance of the design section. On the other hand, horizontal forces are more conservative using Pedersen and Nørgaard equations, obtaining the lowest value with Martin. Regarding uplift pressures, Martin gives the lowest value, while the most conservative values are given by Günbak and Gökce’s for two scenarios, and Pedersen and Nørgaard for the other two scenarios. Furthermore, the sliding safety coefficient is more conditioning than overturning the safety coefficient in all the scenarios.

Os contaminantes de interesse emergente (CIE) incluem, entre outros, produtos de cuidado pessoal, fármacos, pesticidas e cianotoxinas produzidas por cianobactérias tóxicas. A água é o veículo preferencial para transportar os CIE através de diferentes compartimentos ambientais. Alguns destes compostos podem ter efeitos tóxicos, cancerígenos, mutagénicos e de desregulação endócrina em concentrações muito reduzidas, e os seus efeitos sinergéticos e crónicos estão ainda pouco documentados ou são desconhecidos. Neste artigo discutem-se soluções tecnológicas para controlo de CIE em ETA e ETAR.

A prestação dos serviços de água e esgotamento sanitário depende de infraestruturas constituídas por ativos de longa duração, com elevados custos de investimento, de construção e de reabilitação. Por essa razão, a gestão de ativos, ou seja, a gestão estratégica e racional de infraestruturas, é atualmente reconhecida como indispensável para a eficiência, a eficácia e a sustentabilidade dos serviços. Porém, essa prática ainda não está generalizada, havendo um longo caminho a percorrer. Os reguladores do setor têm uma especial responsabilidade para alterarem a situação, sensibilizando a sociedade e os decisores políticos, contribuindo para uma cultura de gestão que inclua o longo prazo, criando medidas promotoras de gestão de ativos. Este artigo contextualiza o tema e sistematiza medidas de regulação promotoras de uma melhor gestão de ativos.

Two pilot trials of powdered activated carbon (PAC)/(coagulation)/ceramic microfiltration were conducted to compare continuous 10–12 mg/L PAC inline dosing with 8–10 mg/L dosing to a 2 h-contact tank. Two low turbidity/low natural organic matter (NOM, total organic carbon <2 mg C/L) surface waters spiked with 7.2–10.3 µg/L total-pesticides were tested and the dosing options were compared towards operational performance, average removal of pesticides and NOM and costs.

The Paraíba and Pernambuco basins are part of the Northeast Brazilian rift system, which contains a series of Cretaceous terrestrial to marine sediments covered by Neogene-Quaternary deposits. Their main aquifers (i.e. Barreiras, Beberibe, Cabo, Quaternary and, Fractured) constitute multi-layered aquifer systems and are the main strategical source of drinking water for the Recife Metropolitan Region. In this research, 323 physical-chemical samples along with 25 isotopic groundwater analyses were used to characterize the main hydrochemical processes controlling groundwater’s chemistry and to identify recharge sources. Graphical, ionic ratios and multivariate statistical methods were used to achieve these goals. The correlation matrix was used to evaluate significant associations between 11 geochemical parameters. Principal Component Analysis was employed and a two-factor model is suggested explaining 72.54% of the total variation within the dataset. PC1 is the major contributor to groundwater mineralization and is assigned to ‘natural’ processes (e.g. rock weathering, ion exchange, etc.), and PC2 is related to ‘anthropogenic’ processes (e.g. nitrate contamination). Hierarchical cluster analysis was employed and partitioned the water samples into 28 distinct hydrochemical water clusters (B1–B4, Barreiras; BE1–BE6, Beberibe; C1–C6, Cabo; Q1–Q7, Quaternary; and F1–F5, Fractured). The majority of the cluster samples have Na+–Cl?? to Na+–HCO3?? water type, including the low salinity groundwater, which in a first approximation could be spatially tied to the recharge zones, and intermediate ones probably related to transition zones. Na+–Cl?? to mixed–Cl?? water type is typical for high salinity groundwater that more probably results from mixing with infiltrating highly mineralized water. The groundwaters’ major ion compositions are primarily controlled by the following interactions: (1) mixing of Pleistocene marine transgression with meteoric Holocene infiltrating water, besides atmospheric deposition; (2) water–rock interactions from silicate rock-forming minerals; (3) ion-exchange reactions; and (4) input from animal/human wastewater. The analyzed groundwater samples showed isotopic signature ranging from ?? 1.98 to +0.36‰ and ?? 2.0 to +7.0‰ for ?18O and ?2H respectively, which is similar to precipitation. These isotopic depleted signatures suggest that most of the deep groundwater was likely recharged from colder epochs and/or from a selection of winter infiltrating precipitation through time.