1,032 research outputs found
Backbarrier shores along the Ria Formosa lagoon
Low energy beaches are located in sheltered and fetch-limited environments. The fetch, also called the fetch length, is the uninterrupted distance over the sea surface for which the wind can blow without a change in direction and affects the growth of wind-waves. Fetch-limited beaches are found in estuaries and bays (e.g. Chesapeake Bay, USA), behind ocean barriers (e.g. Pamlico Sound, USA), adjacent to inlets (e.g. Tapora Bank,
New Zealand), deltas (e.g. Menderes River, Turkey), eroding thermokarst (e.g. Yensei Bay, Russia), and glacial outwash fans (e.g. Canal Baker, Chile; Cooper et al., 2007). In the case of barrier island systems, the back of barrier islands facing the lagoon environments i.e., backbarrier shores are fetch-limited environments.
A barrier is an elongated ridge that is composed predominantly of unconsolidated sand and/or gravel and protect the adjacent mainland from open-water processes (Figure 2.1). From the sea to the mainland, the barriers are generally composed of the shoreface, dune and backbarrier environments, and they are separated alongshore by tidal inlets (Figure 2.1). Barrier islands are dynamic systems, constantly on the
move, migrating under the influence of waves, tides, currents, storms, and changing mean sea levels. The backbarrier is a narrow, elongated, intertidal landform that is located on the lagoon or estuary side of the barrier island and can take the form of sandy beaches, tidal flats or salt marshes (Figure 2.1). Backbarrier beaches tend to be morphodynamically reflective (according to the classification of Wright & Short, 1984),
with steep narrow foreshores that have smaller seasonal variations than open ocean beaches. The tidal flat is bound to the foreshore and might end in a salt marsh fringe. Salt marshes are among the most productive ecosystems on earth.info:eu-repo/semantics/publishedVersio
Prediction of overwash in alongshore variable barrier islands [Previsão da ocorrência de galgamentos em ilhas barreira com variabilidade longilitoral]
Overwash prediction is very important for coastal zone
management. This work intends to identify alongshore variations in
storm impact and evaluate the role of sub-aerial and submerged
morphologies in overwash occurrence. For this study, 24 cross-shore
topo-bathymetric profiles were set on Barreta Island (Ria Formosa
barrier island system, Portugal). Pre- and post-overwash surveys were
made between August 2012 and April 2013. During overwash events,
tidal levels and wave parameters at breaking were obtained. Overwash
occurred under storm and non-storm conditions, the latter coincident
with spring high-tide. Beach morphology was spatially variable, and
changeable from one overwash episode to the next. Predictions of
overwash occurrence were made using the Overwash Potential, defined
as the difference between runup and barrier elevation. Several runup
equations were tested, and the results compared to the actual
observations. The selected predictor provided an accuracy of 88% for
the identification of the locations where overwash occurred. This study
proves that nearshore and foreshore morphologies have a major impact
on the longshore distribution of overwash.info:eu-repo/semantics/publishedVersio
Engaging children in geosciences through storytelling and creative dance
Natural sciences have traditionally been disseminated in outreach activities as formal, one-way presentations. Nevertheless, innovative strategies are being increasingly developed using arts, gaming, and sketching, amongst
others. This work aimed at testing an alternative and innovative way to engage non-expert audiences in ocean and coastal
geology through a combination of scientific concept explanations and creative dancing. An informal education activity focusing on ocean dynamics was designed for 10-yearold students. It combines coastal science concepts (wind,
waves, currents, and sand), storytelling techniques (narrative
arc), and creative dance techniques (movement, imaginative
play, and sensory engagement). A sequence of six exercises
was proposed, starting with the generation of offshore ocean
waves and ending with sediment transport on the beach during storm/fair-weather conditions. Scientific concepts were
then translated into structured creative movements, within
imaginary scenarios, and accompanied by sounds or music.
The activity was performed six times with a total of 112 students. It was an inclusive activity given that all students in the
class participated, including children with several mild types
of cognitive and neurological impairment. The science and
art activity aroused emotions of enjoyment and pleasure and
allowed for effective communication between scientists and
school community. Moreover, the results provide evidence of
the activity’s effectiveness in engaging children and developing their willingness to further participate in similar activities.PTDC/MAR-EST/1031/2014/ IF/00354/201/ 57/2016/CP1361/CT0002 and DL 57/2016/CP1432/CT0001info:eu-repo/semantics/publishedVersio
Low-Phytotoxic Deep Eutectic Systems as Alternative Extraction Media for the Recovery of Chitin from Brown Crab Shells
Funding Information: This work was financed by Portugal 2020 through the European Regional Development Fund (ERDF) in the frame of Operational Competitiveness and Internationalization Program (POCI) in the scope of the project MultiBiorefinery—POCI-01-0145-FEDER-016403, co-financed by national funds through the FCT/MEC. Additional funding was received from PTDC/EQU-EQU/29851/2017 project, financed by national funds (FCT/MEC); and from ERC-2016-CoG 725034 grant agreement, financed by the European Union’s Horizon 2020 (European Research Council). This work was also supported by the funding received from INTERFACE Program, through the Innovation, Technology and Circular Economy Fund (FITEC); and from iNOVA4Health (UIDB/04462/2020) and the Associate Laboratory for Green Chemistry—LAQV (UIDB/50006/2020), programs financially supported by FCT/MEC, through national funds. This work has also received support from COST Action CA18224 through an STSM Grant. Liliana A. Rodrigues, Alexandre Paiva, and Ana A. Matias have also received financial support from FCT through the SFRH/BD/116002/2016, IF/01146/2015, and IF/00723/2014 grants, respectively. The authors are grateful to Tejo Ribeirinho Lda. for kindly supplying the biomass used in this work. Publisher Copyright: © 2021 American Chemical Society.The versatility of chitin and its derivatives has allowed their utilization in a wide range of applications, from wastewater treatment to pharmaceutical or biomedical industries. However, even though the extraction method used industrially is extremely efficient, it involves the use of strong acids and bases and results in the disposal of large quantities of toxic effluents. Deep eutectic systems (DESs) have emerged as a promising new class of alternative solvents, including for chitin recovery. Yet, the assessment of their toxicity has often been neglected. Therefore, in this work, the phytotoxicity of choline chloride (ChCl)/organic acid-based DESs toward wheat seeds was evaluated by measuring different growth parameters and stress biomarkers. DESs were then explored for the efficient recovery of chitin contained in brown crab shell residues at varying conditions of temperature and processing time as well as with and without water addition. The obtained chitin was then characterized through different analytical techniques and compared to a standard as well as to chitin obtained by a conventional acid/alkaline hydrolysis. Results have shown that by applying a ChCl/lactic acid-based DES (which was the system that showed the least phytotoxic effects on wheat; EC50 ≥ 1.6 mg/mL) at 130 °C, it was possible to obtain pure chitin (up to 98%) with characteristics similar to those presented by commercial chitin or chitin recovered by conventional hydrolysis in a shorter time (more than 8-fold faster), thus suggesting that ChCl/organic acid-based DESs can truly represent a low-phytotoxic alternative extraction media for the recovery of chitin from the crab shell biomass.publishersversionpublishe
Environmental risk assessment in a contaminated estuary: an integrated weight of evidence approach as a decision support tool
Environmental risk assessment of complex ecosystems such as estuaries is a challenge, where innovative
and integrated approaches are needed. The present work aimed at developing an innovative integrative
methodology to evaluate in an impacted estuary (the Sado, in Portugal, was taken as case study), the
adverse effects onto both ecosystem and human health. For the purpose, new standardized lines of
evidence based on multiple quantitative data were integrated into a weight of evidence according to a
best expert judgment approach. The best professional judgment for a weight of evidence approach in the
present study was based on the following lines of evidence: i) human contamination pathways; ii)
human health effects: chronic disease; iii) human health effects: reproductive health; iv) human health
effects: health care; v) human exposure through consumption of local agriculture produce; vi) exposure
to contaminated of water wells and agriculture soils; vii) contamination of the estuarine sedimentary
environment (metal and organic contaminants); viii) effects on benthic organisms with commercial
value; and ix) genotoxic potential of sediments. Each line of evidence was then ordinally ranked by levels
of ecological or human health risk, according to a tabular decision matrix and expert judgment. Fifteen
experts scored two fishing areas of the Sado estuary and a control estuarine area, in a scale of increasing
environmental risk and management actions to be taken. The integrated assessment allowed concluding
that the estuary should not be regarded as impacted by a specific toxicant, such as metals and organic
compounds hitherto measured, but by the cumulative risk of a complex mixture of contaminants. The
proven adverse effects on species with commercial value may be used to witness the environmental
quality of the estuarine ecosystem. This method argues in favor of expert judgment and qualitative
assessment as a decision support tool to the integrative management of estuaries. Namely it allows
communicating environmental risk and proposing mitigation measures to local authorities and population
under a holistic perspective as an alternative to narrow single line of evidence approaches, which
is mandatory to understand cause and effect relationships in complex areas like estuaries.info:eu-repo/semantics/publishedVersio
Antioxidant activity and cytotoxicity of solubilized C60 and its conjugates with butylated hydroxytoluene
It has been described that fullerenes (C60) present interesting properties with potential
application in clinical conditions related to oxidative stress. One of the most prominent features of fullerenes is the ability to quench free radicals. However, because of its poor solubility, this has been studied mostly in organic solutions,
while the antioxidant activity and cytotoxicity of fullerenes and their derivates in aqueous medium is not well characterized. The antioxidant capacity of synthesised C60-conjugates has been investigated and its was higher comparing to C60 isolated. The aim of this study was to assess the viability of C60-conjugates by determining its antioxidant activity and cytotoxicity in bio-relevant media
A new competitive implementation of the electromagnetism-like algorithm for global optimization
The Electromagnetism-like (EM) algorithm is a population-
based stochastic global optimization algorithm that uses an attraction-
repulsion mechanism to move sample points towards the optimal. In
this paper, an implementation of the EM algorithm in the Matlab en-
vironment as a useful function for practitioners and for those who want
to experiment a new global optimization solver is proposed. A set of
benchmark problems are solved in order to evaluate the performance of
the implemented method when compared with other stochastic methods
available in the Matlab environment. The results con rm that our imple-
mentation is a competitive alternative both in term of numerical results
and performance. Finally, a case study based on a parameter estimation
problem of a biology system shows that the EM implementation could
be applied with promising results in the control optimization area.Acknowledgments This work has been supported by FCT (Funda¸c˜ao para a Ciˆencia e Tecnologia, Portugal) in the scope of the project PEst-UID/CEC/00319/2013
Microwave pretreatment to improve extraction efficiency and polyphenol extract richness from grape pomace. Effect on antioxidant bioactivity
Producción CientíficaMicrowave assisted extraction advantages are widely recognised. However, its implementa-tion at industrial scale is restricted due to microwave limitations. In this work, a microwavepretreatment is proposed as an easy scale-up alternative for grape pomace polyphenolextraction, especially for anthocyanins. The double effect of this pretreatment on extractionyield and on product richness is assessed. Microwaves accelerate the extraction kineticsof most compounds, but their effect on polyphenols is more pronounced than in othersubstances (like sugars and fibres). These differentiated rates are exploited to improve thepolyphenol richness of the final dry product. By selecting the appropriate operating condi-tions, polyphenol yield was increased by 57% and, simultaneously, dry product richness wasenhanced by 32%. Also, anthocyanin extraction boost was remarkable. Its content in the finaldry product was 85% higher than the one obtained without the microwave pretreatment.The cellular bioactivity of these extracts was improved by 83% and 133%
Isolation of bluish anthocyanin-derived pigments obtained from blueberry surplus using centrifugal partition chromatography
Funding Information: This work was funded by Fundação para a Ciência e Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior (FCT/MCTES, Portugal) through national funds to iNOVA4Health (UIDB/04462/2020 and UIDP/04462/2020), the Associate Laboratory LS4FUTURE (LA/P/0087/2020) and Associated Laboratory for Sustainable Chemistry, Clean Processes, and Technologies LAQV (UIDB/50006/2020 and UIDP/50006/2020). Funding from INTERFACE Programme, through the Innovation, Technology and Circular Economy Fund (FITEC), is gratefully acknowledged. A.N.N. acknowledge FCT for the financial support received through SFRH/BD/144592/2019. J.O. acknowledge FCT her research contract (2022.00042.CEECIND/CP1724/CT0017). The authors also acknowledge Delícias do Tojal, CultiBaga, and Mirtilsul for kindly supplying the biomass. Funding Information: This work was funded by Fundação para a Ciência e Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior (FCT/MCTES, Portugal) through national funds to iNOVA4Health ( UIDB/04462/2020 and UIDP/04462/2020 ), the Associate Laboratory LS4FUTURE ( LA/P/0087/2020 ) and Associated Laboratory for Sustainable Chemistry, Clean Processes, and Technologies LAQV ( UIDB/50006/2020 and UIDP/50006/2020 ). Funding from INTERFACE Programme, through the Innovation, Technology and Circular Economy Fund ( FITEC ), is gratefully acknowledged. A.N.N. acknowledge FCT for the financial support received through SFRH/BD/144592/2019 . J.O. acknowledge FCT her research contract ( 2022.00042.CEECIND/CP1724/CT0017 ). The authors also acknowledge Delícias do Tojal, CultiBaga, and Mirtilsul for kindly supplying the biomass. Publisher Copyright: © 2023 The Author(s)Replacement of synthetic colorants with natural ones is a current marketing trend. Nevertheless, the naturally occurring blue color is rare compared to other colours. In this work, centrifugal partition chromatography (CPC) process was developed as a more efficient and sustainable alternative to reversed phase column chromatography (RP-CC) for the preparative-scale purification of portisins. The strategy began with the extraction of anthocyanins from blueberry surplus and hemi-synthesis of respective portisins. Then, the CPC method development started with the biphasic solvent system selection followed by the optimization of the operating parameters and ended up with a comparison with RP-CC. Aiming at maximizing the portisin content, process throughput, efficiency, and minimizing the environmental risk factor, the effect of sample load (100–500 mg/100 mL of column volume), mobile phase flow rate (10–20 mL/min), and rotation speed (1000–1600 rpm) was evaluated. The two-phase solvent system consisted of tert‑butyl‑methyl ether, n-butanol, acetonitrile, and water (volume ratio 2:2:1:5) acidified with 0.1 vol.% of HCl was selected. The best conditions were 464 mg of sample/100 mL of column volume, 20 mL/min of mobile phase flow rate, and 1600 rpm of rotation speed at reversed phase mode, allowing the purification of portisins by 5-fold. Compared to the RP-CC, the CPC process efficiency was 2.4 times higher, while the CPC process environmental risk factor was 5.5 times lower. Overall, this study suggests that CPC can be considered an effective, and sustainable alternative process for the preparative isolation of portisins. With this purification approach, the blueberry surplus has been valorized and a naturally derived product has been prepared, allowing its subsequent use as a natural blue colorant.publishersversionpublishe
Process intensification by microwave pretreatment
Arbutus unedo L., commonly known as the strawberry-tree fruit, is an endemic species of the Mediterranean flora. Microwave extraction technology has been considered as a fast and "green" method for the production of extracts rich in bioactive compounds, although the energy consumption is high. To overcome this bottleneck, microwave was used as a pretreatment procedure in short time periods. This technique promotes the burst of intracellular vacuoles leading to an increase in the lixiviation of phenolic compounds. Different approaches were tested, namely a solvent-free irradiation (SFI), a solvent-assisted irradiation (SAI) and a pressurized solvent-assisted irradiation (PSAI). After irradiation, a solid-liquid extraction procedure was performed using a mixture of water and ethanol. A kinetic evaluation of the total phenolic content (TPC) was performed using the Folin-Ciocalteu method. For the total anthocyanin content, a UV-spectrophotometric method was used. HPLC-UV and LC-MS were used for TPC and identification of present compounds. Microwave irradiation led to an increase in TPC of extracts after SAI (52%) and PSAI (66%) along with a reduction in time of extraction from 30 min to less than 2 min. The anthocyanin content also increased by 66% for the SAI and PSAI extractions.publishersversionpublishe
- …