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FCT2-Artigos (em revistas ou actas indexadas)

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  • Impact and size selectivity of fishing gears used in estuarine crab fisheries
    Publication . Monteiro, João Nuno; Ovelheiro, Andreia; Teodosio, Maria; Leitão, Francisco
    Crustacean fisheries have expanded in the last decade due to the high economic value of the species. However, estuarine crustacean fisheries remain poorly studied compared with marine crustacean fisheries. In Portugal, the European green crab ( Carcinus maenas) may become increasingly important for the fishing industry and seafood production in general, especially in the current context of overexploitation of estuarine traditional fisheries resources. The unknown ecological impact of crab fishing gear and its size-selectivity characteristics constrain gear regulations by fisheries authorities. We developed an integrated study over three years to analyse a C. maenas fishery in three Portuguese estuarine systems aiming to: 1) describe the fishing characteristics and modus operandi of the fishing gears; 2) analyse gear selectivity and catch rates; 3) analyse environmental impact of fishing gears; 4) Contribute to supporting better regulations for the fishery. Two types of crab fishing gear are used, box traps and drop nets. Daily catches of green crabs varied by gear, system, and month, with the highest catches observed in box traps during the warmest months. Selectivity studies indicate that a mesh size of 18 mm in box traps and 30 mm in drop nets would allow crabs larger than the minimum landing size (40 mm carapace width) to be targeted while maximising catch rates. However, regardless of the mesh size, the catch from both gears will need to be sorted to exclude juveniles from the catch. The bar spacing, which allows crabs to be sorted according to the minimum landing size, is 17 mm. Gears present none (drop nets) or low by-catch (220 g or 23 individuals/40 box traps), which was promptly discarded, indicating a low impact on estuarine communities. The methodology used in this study, which combines ecological impacts and technical gear issues (selectivity), can be directly applied to enforce regulations and improve sustainable exploitation of socio-economically important artisanal fisheries.
  • Anomaly detection in all-sky images: An approach using robust ensemble modeling of cloud cover fraction and prediction bounds
    Publication . Rocha, Vinicius Roggério da; Fisch, Gilberto; Costa, Rodrigo Santos; Ruano, Antonio
    All-sky images (ASI) are widely used for sky monitoring, particularly in solar energy generation applications. Alignment issues and interferences demand a detection process of problematic images. With high sampling frequencies (1-2 images per minute), automating this process is crucial for managing large datasets and enabling integration into automatic systems, which is the objective of this work. For this purpose, a robust ensemble model, using the ApproxHull and Radial Basis Function (RBF) neural networks combined with Multi Objective Genetic Algorithms (MOGA) tools, was developed to compute the cloud cover fraction of each image. By computing the deviation between this result and the one obtained by the equipment, and by assessing if it lies within prediction bounds obtained in the design phase, an automatic method for detecting anomalies in All-sky images was obtained. ASI data collected during the Green Ocean (GoAmazon) Experiment 2014/5 was employed. The proposed approach obtained a Probability of Interval Coverage (PICP) similar to the user- specified level of confidence for several sets within what was classified as a "good"dataset, while being able to detect anomalies found within a "bad"dataset.
  • Medicines, the haute couture of pharmacy: a summer camp for high school students
    Publication . Fonseca, Custódia
    Since ancient times, man has prepared medicines and used them in healing practices. Therefore, there has always been a great interest in the part of people in general and students in particular about medicines. The "Medicines, the Haute Couture of Pharmacy" summer camp has the objective to promote and improve the literacy in medicines and make participants aware of, and become interested in, pharmaceutical sciences. It is a five-day summer camp where high-school students learn about medicines, how they are constituted, how they work, and how they are formulated. This occurs through hands-on synthesis and isolation of bioactive molecules, namely, acetylsalicylic acid, ibuprofen, and limonene, and subsequent formulation of pharmaceutical forms such as tablets, capsules, suppositories, and creams. Participant survey responses showed that they are very satisfied with this summer camp and the knowledge acquired, which may help them make their future career choices.
  • The escarpão plateau (South of Portugal)—a study case of nested geosites from the aspiring Algarvensis geopark
    Publication . Veiga-Pires, Cristina; Jenkins Oliveira Fernandes, Sónia Alexandra; Moura, Delminda; Pereira, Luís
    Located along the southern limit of the Algarvensis aspiring UNESCO Global Geopark (aUGGp), the Escarpão Plateau is a singular geomorphological structure sculpted by fluvial, karst, and tectonic processes. The plateau is deeply scarved by the Quarteira Rivulet, forming a valley that crosses the most complete Upper Jurassic sedimentary sequence of the Eastern Algarve (Southern Portugal). This sequence includes five geological formations representing different depths of carbonate ramp deposition from the Tethys Sea: Peral Formation, Jordana Formation, Cerro da Cabeça Formation, Escarpão Formation, and the upper Limestone Formation with Anchispirocyclina lusitanica (foraminifera), respectively from the oldest formation to the most recent at the top. Throughout the Quaternary Period, the karst processes shaped a landscape of sparse and poor soils, based on which successive generations adapted their subsistence agriculture and way of life. The geomorphology of the plateau and the rivulet valley, the sequence of the carbonated formations, and the diversity of sedimentary and paleontological records can be considered possible sites of diverse geological interest and with different scales that are embedded in each other, forming thus nested sites. To promote and preserve these sites, the Algarvensis aUGGp shaped an 8-km-long interpretative walking path, passing through 11 points of interest, including biosites and geosites. Their interpretative boards highlight not only the different spatial and temporal geological diversity but also its relationship with surrounding cultural and historical heritage. Finally, this work allowed the creation of new products for outreach and public awareness towards an effective geoconservation.
  • Continuous/discontinuous finite element approximation of a 2d navier-stokes problem arising in fluid confinement
    Publication . Borges de Oliveira, Hermenegildo; Lopes, Nuno David
    In this work, a stationary 2d Navier-Stokes problem with nonlinear feedback forces field is considered in the stream -function formulation. We use the Continuous/Discontinuous Finite Element Method (CD-FEM), with interior penalty terms, to numerically solve the associated boundary -value problem. For the associated continuous and discrete problems, we prove the existence of weak solutions and establish the conditions for their uniqueness. Consistency, stability and convergence of the method are also shown analytically. To validate the numerical model regarding its applicability and robustness, several test cases are carried out.
  • Inhibitory potency of active metabolites from different polarities of Datura Stramonium seed extracts: GC-MS analysis, biological evaluations, and molecular docking studies
    Publication . Hjouji, K.; El Barnossi, A.; Er-rajy, M.; Atemni, I.; Grenha, Ana; Yagoubi, M.; Ainane, T.; Taleb, M.; Rais, Z.
    Datura Stramonium is a well-known and important medicinal plant that is widely used in various medical systems to treat conditions such as asthma, diabetes, and inflammatory diseases. The aim of this study was to prepare extracts of D. stramonium seeds in different solvent polarities for assessing phytochemical potential, in vitro biological activities, and molecular docking studies. Phytochemical screening was conducted to determine the phytochemical composition, while GC-MS analysis was used to identify secondary metabolites of D. Stramonium. The seed extracts were molecularly docked to evaluate bioactive and antioxidant activity. The minimum inhibitory concentration (MIC) of the extracts against bacteria such as S. aureus, E. coli, Bacillus subtilis, and Proteus mirabilis was determined. Antifungal activity was also tested against fungi including Aspergillus fl avus, Fusarium oxysporum, Aspergillus niger, and Candida albicans. The results of phytochemical screening indicated that the primary plant constituents in all extracts of different polarities are alkaloids, flavonoids, tannins, mucilage, sterols, heterosides, triterpenoids, and cardiac glycosides. Most molecules in the hexane, ether, and chloroform extracts consist of fatty acids, sterols, glycosides, triterpenoids, alkaloids, and phenolic compounds, as revealed by GC-MS analysis. Conversely, extracts from polar solvents like methanol, ethanol, and water are abundant in alkaloids. In vitro antibacterial and antifungal activities demonstrated that ether, methanol, and ethanol extracts were more effective than inhibiting the four bacterial strains compared to the antibiotics Oxacillin and Cefuroxime. The ether and methanol extracts exhibited better zones of inhibition and significant MIC values against A. niger and C. albicans compared to the control and fluconazole. The free radical inhibition (DPPH) (24.92 5.31 m g/mL) for the ethanol extract indicates Datura's antioxidant capacity. It is believed that the main phytochemicals are responsible for the enhanced antioxidant activity observed in other studies. The docking study revealed that the bioactive compounds linoleic acid and atropine formed better hydrogen bonding interactions with proteins than pi-alkyl and alkyl bonds. (c) 2024 SFMM. Published by Elsevier Masson SAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
  • Common dolphin's shipping noise risk assessment on the Portuguese coast
    Publication . Spadoni, Giulia; Duarte, Ricardo; Soares, Cristiano; Fernandez, Marc; Jesus, Sergio
    Ocean noise generated by human activities at sea has been increasing over the decades, affecting marine eco systems. Ship traffic flow between the Mediterranean or South Atlantic and northern Europe makes the coast of Portugal one of the most intense shipping highways on a global scale. Among the cetaceans of the coast of Portugal, the common dolphin (Delphinus delphis) was selected as a target species. Based on 15 years of obser vations, the common dolphins' habitat suitability was estimated, together with the shipping noise maps for the year 2019, to produce seasonal risk maps for the same year. A large number of areas with a high noise risk index (≥0.85) were found in Portugal's southern and southwestern coasts, especially during the summer and fall seasons. Comparably, the 0.50 risk index exceeds 7 % and 3.5 % of the total area in summer and fall, respec tively. These percentages decrease to 1 % in spring and winter.
  • Enhancing growth, nutrient uptake and flowering of Tagetes patula plants through the application of suspensions of Chlorella vulgaris
    Publication . Vieira, João; Saque, Moisés; Viana, Catarina; Rodrigues, Maria Helena; Guerreiro David Coelho, Luísa Isabel; Gama, Florinda; Varela, João; Pereira, Hugo; Reis, Mário; Pestana, Maribela; Correia, Pedro José
    Tagetes patula L. is a prominent plant that is frequently used for its ornamental value. Marigolds are sources of various compounds of great interest to agricultural, pharmaceutical, and nutritional industries. Microalgae can be applied as a biostimulant as they have multifunctional properties in agriculture, namely facilitating nutrient uptake, improving crop performance and physiological status, and thus increasing tolerance to abiotic stress. This study evaluated the efect of applying Chlorella vulgaris as a plant biostimulant on the growth and fowering of T. patula plants. Microalgae suspensions were applied to the substrate at concentrations of 0.5, 2.0 and 5.0 g dry weight (DW) L−1. A set of plants without the application of microalgae was used as control. The use of microalgae had a positive impact on plant growth. Specifcally, C. vulgaris application resulted in greater height, while the highest concentration (5.0 g DW L−1) resulted in higher fresh weight. Microalgae application signifcantly promoted the earlier fowering of marigolds. The macronutrient and micronutrient values were statistically similar between the control plants and those treated with microalgae. When considering only the treated plants, there was a signifcant correlation between the concentration of C. vulgaris and the concentrations of N, P, Mn and Cu in the shoots of T. patula plants. Plants receiving higher concentrations of C. vulgaris exhibited higher levels of these nutrients. These results highlight the potential use of Chlorella vulgaris as an efective biostimulant for enhancing the growth, fowering, and nutrient uptake of T. patula, ofering valuable applications for improving ornamental plant production and, ultimately, agricultural sustainability.
  • Thermal responses of tetradesmus obliquus for industrial outdoor cultivation
    Publication . Kato, Hidehiko; Suzuki, Hirono; Wijffels, René H.; Schulze, Peter S.C.; Hulatt, Chris J.
    In microalgae cultivation systems, fluctuating temperatures impact growth rates and biomass quality, whilst extremes of temperature can lead to the loss of large-scale cultures. Evaluation and selection of strains based on their performance under different temperatures could offer substantial improvements by reducing costs and increasing yields. Here the thermal performance of Tetradesmus obliquus UTEX393 was compared with a novel isolate of the same species, SNS0120, using turbidity-controlled flat-panel photobioreactors. UTEX393 showed higher growth performance at all temperatures and a higher thermal limit compared to SNS0120. Total fatty acids were not influenced by temperature, but the fatty-acid profiles varied, and omega-3/6 ratios were lower under high temperatures. Transcriptomic analysis of UTEX393 showed that temperature caused substantial shifts in gene expression, with 4971 significantly differentially expressed genes during a temperature upshift from 10 ◦C (low temperature) to 25 ◦C (optimal temperature), and 3683 genes significantly differentially expressed from 25 ◦C (optimal temperature) to 34 ◦C (high temperature).
  • Lignin-furanic rigid foams: Enhanced methylene blue removal capacity, recyclability, and flame retardancy
    Publication . Duarte, Hugo; Brás, João; Saoudi Hassani, El Mokhtar; Aliaño González, María José; Magalhães, Solange; Alves, Luís; Valente, Artur J. M.; Eivazi, Alireza; Norgren, Magnus; Romano, Anabela; Medronho, Bruno
    Worldwide, populations face issues related to water and energy consumption. Water scarcity has intensified globally, particularly in arid and semiarid regions. Projections indicate that by 2030, global water demand will rise by 50%, leading to critical shortages, further intensified by the impacts of climate change. Moreover, wastewater treatment needs further development, given the presence of persistent organic pollutants, such as dyes and pharmaceuticals. In addition, the continuous increase in energy demand and rising prices directly impact households and businesses, highlighting the importance of energy savings through effective building insulation. In this regard, tannin-furanic foams are recognized as promising sustainable foams due to their fire resistance, low thermal conductivity, and high water and chemical stability. In this study, tannin and lignin rigid foams were explored not only for their traditional applications but also as versatile materials suitable for wastewater treatment. Furthermore, a systematic approach demonstrates the complete replacement of the tannin-furan foam phenol source with two lignins that mainly differ in molecular weight and pH, as well as how these parameters affect the rigid foam structure and methylene blue (MB) removal capacity. Alkali-lignin-based foams exhibited notable MB adsorption capacity (220 mg g−1), with kinetic and equilibrium data analysis suggesting a multilayer adsorption process. The prepared foams demonstrated the ability to be recycled for at least five adsorption-desorption cycles and exhibited effective flame retardant properties. When exposed to a butane flame for 5 min, the foams did not release smoke or ignite, nor did they contribute to flame propagation, with the red glow dissipating only 20 s after flame exposure.