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  • Local fishermen’s perceptions of the usefulness of artificial reef ecosystem services in Portugal
    Publication . Ramos, Jorge; Lino, Pedro G.; Himes-Cornell, Amber; Santos, Miguel N.
    Proponents of artificial reef (AR) deployment are often motivated by the usefulness of such structures. The usefulness of ARs is related to their capability of providing ecosystem services/additional functions. We present two distinct Portuguese AR case studies: (1) The Nazaré reef off the central coast of Portugal and (2) the Oura reef off the Algarve coast. Semi-structured interviews were conducted with local fishermen in the fishing towns of Nazaré and Quarteira pre-and post-AR deployment. The main focus of the interviews was to understand fishermen’s perception of AR usefulness (or lack thereof) in terms of nine ecosystem services/additional functions potentially provided by the ARs. We tested the null hypothesis that ARs do not provide additional ecosystem services/additional functions. When queried pre-AR deployment, fishermen indicated that ARs are most likely to provide three ecosystem services: “habitat and refuge,” “biodiversity preservation” and “food production.” Fishermen had similar perceptions post-deployment. For the Nazaré reef, fishermen tended to have a positive or neutral perception of ecosystem services/additional functions being provided by ARs. For the Oura reef, fishermen tended to have a mostly neutral perception of AR ecosystem services; however, there were also some positive and other negative perceptions. It was difficult for stakeholders to conceptualize some of the ecosystem services/additional functions provided by ARs prior to actively using them. As a result, some stakeholders changed their perception of the ecosystem services/additional functions after using the structures. These results indicate that stakeholders likely need to perceive ARs as useful in order for them to provide their support for AR installation. Likewise, their support is often needed to justify the use of public funds to install ARs, therefore making it imperative for resource managers to undertake similar interviews with fishermen when considering the use of ARs in other areas.
  • Macroplastics as reservoirs of antimicrobial resistance: a systematic review of evidence, variability and methodological constraints
    Publication . Costa, Cátia; Duarte Ferreira, Guilherme; Henriques, Isabel; Tacão, Marta; Campos, Maria Jorge
    The environmental accumulation of macroplastics has raised concerns regarding their role in the spread of antimicrobial resistance (AMR). As persistent and mobile substrates, macroplastics provide surfaces for microbial colonization and may act as reservoirs and vectors of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs). However, their ecological significance remains insufficiently resolved. Following PRISMA guidelines, we conducted a systematic review of 55 peer-reviewed studies investigating environmentally collected and experimentally exposed macroplastics across marine, estuarine, and freshwater systems. Macroplastics consistently harbor clinically relevant ARB and ARGs, supporting their role as AMR reservoirs. However, evidence for systematic enrichment relative to surrounding matrices is inconsistent, and direct evidence of AMR transfer during environmental transport remains limited. Anthropogenic pressure, ecosystem type, and plastic weathering emerged as key drivers of AMR patterns, with freshwater systems typically showing higher abundance and diversity of ARB and ARGs. Weathering enhances biofilm development and the adsorption of selective agents, whereas the influence of polymer type remains inconclusive. Methodological heterogeneity, including inconsistent quantification strategies, limited environmental controls, and lack of phenotype-genotype linkage, constrains robust inference. We propose a standardized, integrative framework combining environmental baselines, harmonized AMR quantification, and functional validation to improve comparability and support reliable evaluation of macroplastic-associated AMR.
  • Current Strategies to Produce 3D Electrospun-Based Wound Dressings for Skin Regeneration
    Publication . Ferreira, Carolina A. M.; Lemos, Marco F. L.; Maurício, Ana Colette; Dias, Juliana R.
    Tissue engineering-based wound dressings are a promising treatment approach that mimics the native skin microenvironment to promote effective healing and tissue regeneration. In fact, those advanced wound dressings can be made by electrospinning which has revolutionized the field of wound healing by developing biostructures that closely mimic the skin’s extracellular matrix (ECM). To date, most electrospinning research has focused on composition and materials rather than exploring advanced deposition strategies. Conventional electrospinning using random, aligned fibers, co-electrospinning, core-shell approaches, or redesigned collectors has achieved significant results in wound healing, which are discussed in this article. However, these approaches lack the development of realistic 3D structures. To achieve that, advancing approaches through the combination of electrospinning with different techniques such as gas foaming, short nanofiber assembly, or 3D printing significantly enhance skin regeneration of deep wounds (full-thickness and chronic wounds) compared to 2D structures. This review highlights the latest developments, design principles, and recent breakthroughs in electrospinning structures for skin regeneration and provides a fresh perspective for upcoming research in the field of 3D electrospun-based structures.
  • An integrative assessment to determine the genotoxic hazard of estuarine sediments: combining cell and whole-organism responses
    Publication . Costa, Pedro M.; Pinto, Miguel; Vicente, Ana M.; Gonçalves, Cátia; Rodrigo, Ana P.; Louro, Henriqueta; Costa, Maria H.; Caeiro, Sandra; Silva, Maria J.
    The application of the Comet assay in environmental monitoring remains challenging in face of the complexity of environmental stressors, e.g., when dealing with estuarine sediments, that hampers the drawing of cause-effect relationships. Although the in vitro Comet assay may circumvent confounding factors, its application in environmental risk assessment (ERA) still needs validation. As such, the present work aims at integrating genotoxicity and oxidative DNA damage induced by sediment-bound toxicants in HepG2 cells with oxidative stress-related effects observed in three species collected from an impacted estuary. Distinct patterns were observed in cells exposed to crude mixtures of sediment contaminants from the urban/industrial area comparatively to the ones from the rural/riverine area of the estuary, with respect to oxidative DNA damage and oxidative DNA damage. The extracts obtained with the most polar solvent and the crude extracts caused the most significant oxidative DNA damage in HepG2 cells, as measured by the formamidopyrimidine-DNA glycosylase (FPG)-modified Comet assay. This observation suggests that metals and unknown toxicants more hydrophilic than polycyclic aromatic hydrocarbons may be important causative agents, especially in samples from the rural part of the estuary, where oxidative DNA damage was the most significant. Clams, sole, and cuttlefish responded differentially to environmental agents triggering oxidative stress, albeit yielding results accordant with the oxidative DNA damage observed in HepG2 cells. Overall, the integration of in vivo biomarker responses and Comet assay data in HepG2 cells yielded a comparable pattern, indicating that the in vitro FPG-modified Comet assay may be an effective and complementary line-of-evidence in ERA even in particularly challenging, natural, scenarios such as estuarine environments.
  • A destination imagery processing model: Structural differences between dream and favourite destinations
    Publication . Cardoso, Lucília; Dias, Francisco; Araújo, Arthur Filipe de; Marques, Maria Isabel Andrés
    The present paper aims at understanding how destination imagery is processed in tourists’ working memory. The research focuses on two highly desirable, but contrasting, destination brand categories: Favourite Destination, which involves retrospective memory of positive experiences in situ; and Dream Destination, based on tourists’ prospective memory. Through an online multilingual survey, 23,446 responses consisting of perceptions, evoked by way of free-recall, associated to Dream and Favourite Destinations, were collected. Findings point to clear structural differences between the imagery of Dream and Favourite Destinations. Additionally, a theoretical destination imagery model that offers a basis for future studies is proposed, and some managerial implications of significant relevance to destination marketing are discussed.
  • Production of Human Milk Fat Substitutes Catalyzed by a Heterologous Rhizopus oryzae Lipase and Commercial Lipases
    Publication . Simões, Tiago; Valero, Francisco; Tecelão, Carla; Ferreira-Dias, Suzana
    This study aims to produce human milk fat substitutes by an acidolysis reaction between lard and the free fatty acids (FFA) from a fish oil concentrate rich in docosahexaenoic acid, in solvent-free media. The immobilized commercial lipases from (1) Rhizomucor miehei (Lipozyme RM IM), (2) Thermomyces lanuginosa (Lipozyme TL IM) and (3) Candida antarctica (Novozym 435) were tested as biocatalyst. Also, the heterologous Rhizopus oryzae lipase (rROL), immobilized in Accurel MP 1000, was tested as a feasible alternative to the commercial lipases. After 24 h of reaction at 50 C, similar incorporations of polyunsaturated fatty acids (c.a. 17 mol%) were attained with Novozym 435, Lipozyme RM IM and rROL. The lowest incorporation was achieved with Lipozyme TL IM (7.2 mol%). Modeling acidolysis catalyzed by rROL and optimization of reaction conditions were performed by response surface methodology, as a function of the molar ratio FFA/lard and the temperature. The highest acidolysis activity was achieved at 40 C at a molar ratio of 3:1, decreasing with both temperature and molar ratio. Operational stability studies for rROL in seven consecutive 24-h batches were carried out. After the fourth batch, the biocatalyst retained about 55 % of the original activity (half-life of 112 h).
  • Understanding the role of destination imagery in mountain destination choice. Evidence from an exploratory research
    Publication . Araújo, Arthur; Cardoso, Lucília; Araújo, Noelia; Dias, Francisco
    The present study explores the imagery of mountain tourism destinations. The research is based on customer-based brand equity and destination choice models, and addresses destination imagery through the concepts favourite destination (FD) and autobiographical memory. Through an online, multilingual survey, 711 responses, consisting of words, associated by a self-selected sample of European mountain tourists to their favourite mountain destinations, were collected. Such data was subjected to a deductive content analysis, and the results suggest that the imagery of favourite mountain destinations consists mostly of functional elements. Findings reinforce previous theories regarding the concept of favourite destinations, destination imagery (DY) processing, and destination choice. Future studies should apply such analysis to other tourism products, as well as to different or more representative samples, to verify whether imagery structures differ. © 2019, Varna University of Management. All rights reserved.
  • Hydrogen peroxide, iodine solution and methylene solution highly enhance the hatching rate of freshwater ornamental fish species
    Publication . Chambel, João; Costa, Ricardo; Gomes, Mónica; Mendes, Susana; Baptista, Teresa; Pedrosa, Rui
    The aim of this study was to evaluate the effect of hydrogen peroxide, iodine solution (PVP) and methylene blue on eggs disinfection of three ornamental fish species, Danio rerio, Pterophyllum scalare and Gymnocorymbus ternetzi. The main idea was to create conditions to enhance the hatching rates. Eggs of each species were exposed to different concentrations of hydrogen peroxide (5, 10, 15 and 25 mg/L), PVP (0.25, 0.5, 0.75 and 1 mg/L) and methylene blue (0.5 1, 2 and 3 mg/L). The optimal doses ranged between species and chemicals: for G. ternetzi, the concentrations that high enhanced the hatching rate were 1 mg/L for the PVP treatment, 25 mg/L for the hydrogen peroxide treatment and 3 mg/L for methylene blue treatment; for P. scalare, the best results were achieved with 25 mg/L for hydrogen peroxide treatment and 3 mg/L for methylene blue treatment. By contrast, for all the different chemical did not increased the D. rerio hatching rate. Results showed that hydrogen peroxide and methylene blue are the most versatile, effective and safe to use in these species. On the other hand, PVP can be used but with many precautions due to very low safety margin. Results clearly show that the optimal concentration of chemicals for eggs disinfection is fish species dependent and it is completely wrong to extrapolate concentrations between different chemicals and fish species. Our study suggests that P. scalare can be used as a model in study of effectiveness of new chemicals with potential to disinfect water and increase hatching rates.
  • Metabolic and histopathological alterations in the marine bivalve Mytilus galloprovincialis induced by chronic exposure to acrylamide
    Publication . Larguinho, Miguel; Cordeiro, Ana; Diniz, Mário S.; Costa, Pedro M.; Baptista, Pedro V.
    Although the neurotoxic and genotoxic potential of acrylamide has been established in freshwater fish, the full breadth of the toxicological consequences induced by this xenobiotic has not yet been disclosed, particularly in aquatic invertebrates. To assess the effects of acrylamide on a bivalve model, the Mediterranean mussel (Mytilus galloprovincialis), two different setups were accomplished: 1) acute exposure to several concentrations of waterborne acrylamide to determine lethality thresholds of the substance and 2) chronic exposure to more reduced acrylamide concentrations to survey phases I and II metabolic endpoints and to perform a whole-body screening for histopathological alterations. Acute toxicity was low (LC50≈400mg/L). However, mussels were responsive to prolonged exposure to chronic concentrations of waterborne acrylamide (1-10mg/L), yielding a significant increase in lipid peroxidation plus EROD and GST activities. Still, total anti-oxidant capacity was not exceeded. In addition, no neurotoxic effects could be determined through acetylcholine esterase (AChE) activity. The findings suggest aryl-hydrocarbon receptor (Ahr)-dependent responses in mussels exposed to acrylamide, although reduced comparatively to vertebrates. No significant histological damage was found in digestive gland or gills but female gonads endured severe necrosis and oocyte atresia. Altogether, the results indicate that acrylamide may induce gonadotoxicity in mussels, although the subject should benefit from further research. Altogether, the findings suggest that the risk of acrylamide to aquatic animals, especially molluscs, may be underestimated.
  • Prevalence of quinolone resistance determinants in non-typhoidal Salmonella isolates from human origin in Extremadura, Spain
    Publication . Campos, Maria Jorge; Palomo, Gonzalo; Hormeño, Lorena; Herrera-León, Silvia; Domínguez, Lucas; Vadillo, Santiago; Píriz, Segundo; Quesada, Alberto
    Resistance to the quinolones nalidixic acid (NAL) and ciprofloxacin (CIP) and the occurrence of quinolone resistance determinants have been investigated in 300 non-typhoidal Salmonella from human origin, isolated in the years between 2004 and 2008, in 6 hospitals within Extremadura (Spain). Salmonella Enteritidis was the major serotype found among quinolone-resistant isolates, most of which were clustered by clonal analysis to a single clone, which presented D87 or S83 substitutions in GyrA. Eleven isolates presented the non-classical quinolone resistance phenotype (resistance to CIP and susceptibility to NAL), lacking mutations in the quinolone resistance determinant region of topoisomerase genes. Among them, one Salmonella Typhimurium isolate carried a qnrS1 gene in a low-molecular-weight plasmid, pQnrS1-HLR25, identical to plasmids previously found in the UK, Taiwan, and USA. The occurrence of this genetic element could represent a risk for the horizontal transmission of quinolone resistance among Enterobacteriaceae in the Iberian Peninsula.