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- Impacts of the Invasive Seaweed Asparagopsis armata Exudate on Energetic Metabolism of Rock Pool InvertebratesPublication . Silva, Carla O.; Novais, Sara C.; Soares, Amadeu M. V. M.; Barata, Carlos; Lemos, Marco F. L.The marine red algae Asparagopsis armata is an invasive species gaining competitive advantage by releasing large amounts of toxic compounds to the surrounding invaded area. The main objective of this study was to evaluate the effects of this invasive seaweed on marine invertebrates by exposing the common prawn Palaemon elegans and the marine snail Gibbula umbilicalis to the exudate of this seaweed. The seaweed was collected and placed in a tank for 12 h in the dark in a 1:10 ratio. Afterwards the seawater medium containing the released secondary metabolites was collected for further testing. Lethal and sublethal effects of A. armata were investigated. Biochemical biomarker responses associated with energy metabolism (lactate dehydrogenase, LDH; electron transport system activity, ETS; lipid, protein and carbohydrate content) were analysed. The biomarker responses showed physiological status impairment of invertebrates after exposure to low concentrations of this algal exudate. The highest concentrations of exudate significantly increased lipid content in both organisms. In the shrimp, protein content, ETS, and LDH were also significantly increased. By contrast, these parameters were significantly decreased in G. umbilicalis. A behavioural impairment was also observed in G. umbilicalis exposed to A. armata exudate, reducing feeding consumption. These results represent an important step in the research of natural toxic exudates released to the environment and prospective effects of this seaweed in invaded communities under increasing global change scenarios.
- Lab Brazil: Parquear Bando digital annotation: on digital scores for collective performance interventions in public spacesPublication . Rosa, Thembi; Fernandes, CarlaParquear Bando is an urban intervention designed for up to 20 people to perform in urban city centres. While describing this urban intervention and analysing parts of the material available in the online pilot publication, we will discuss the limits and potentialities of a digitization process for this improvised performance. We question whether it would be possible to use digital annotations as support for future performances of this collective action without the physical presence of its facilitators but still maintaining the main concerns and principles of Parquear Bando. The three-day workshop shares the intervention’s most common structure and composes a performance to be shown in a selected place of each city. During the Motion Bank Lab Brazil 2019, we started to create a digital archive for the workshop with the aim of finding a consistent documentation model using video annotations, recording interviews and digitizing some of the choreographers’ notebooks. Beyond the digital archive of this urban intervention, we are also interested in making the score and movement principles of this piece available to other groups who could perform Parquear Bando in different contexts.
- An empirical analysis of Lisbon hotel room rates determinantsPublication . Gomes, Conceição; Lima Santos, Luís; Malheiros, CátiaThis study investigates the impact of several characteristics and attributes of hotels on room rates in one of the most visited cities in Europe. The research allows to compare, in a transparent way, findings of previous studies and promotes added value using for the first time the hedonic price model (HPM) in the hospitality industry in Lisbon, Portugal. Although hotel room price determinants have already been studied, in this study it was introduced physical variables and location variables all together, as well as it was added the variables relating to certain services offered. A significant impact on hotel prices by official stars and OTAs punctuation has been confirmed. In line with previous studies, an additional star and belonging to a chain allow the hotel to increase the price. In addition, other attributes, such as the distance of the hotel from the airport and the centre, have impact on hotel prices. The evidence that the existence of a spa and a pool influences hotel prices will support stakeholders in investment and management decision.
- Cholinesterase activity in the caddisfly Sericostoma vittatum: Biochemical enzyme characterization and in vitro effects of insecticides and psychiatric drugsPublication . Pestana, João L. T.; Novais, Sara C.; Lemos, Marco; Soares, Amadeu M. V. M.Sericostoma vittatum is a caddisfly species, endemic to the Iberian Peninsula, proposed as a biomonitor species for lotic ecosystems. Since inhibition of cholinesterases[U+05F3] (ChE) activity has been used to evaluate the exposure of macroinvertebrates to organophosphates and carbamate pesticides, this work intended to characterize the ChE present in this species so their activity can be used as a potential biomarker of exposure. Biochemical and pharmacological properties of ChE were characterized in this caddisfly species using different substrates (acetylthiocholine iodide, propionylthiocholine iodide, and butyrylthiocholine iodide) and selective inhibitors (eserine sulfate, BW284c51, and iso-OMPA). Also, the in vitro effects of two insecticides (carbaryl and chlorantraniliprole) and two psychiatric drugs (fluoxetine and carbamazepine) on ChE activity were investigated. The results suggest that S. vittatum possess mainly AChE able to hydrolyze both substrates acetylthiocholine and propionylthiocholine since: (1) it hydrolyzes the substrate acetylthiocholine and propionylcholine at similar rates and butyrylthiocholine at a much lower rate; (2) it is highly sensitive to eserine sulfate and BW284c51, but not to iso-OMPA; and (3) its activity is inhibited by excess of substrate, a characteristic of typical AChE. in vitro inhibitions were observed only for carbaryl exposure while exposure to chlorantraniliprole and to relevant environmental concentrations of psychiatric drugs did not cause any significant effect on AChE activity. This study suggests that AChE activity in caddisflies can indeed be used to discriminate the effects of specific insecticides in monitoring programs. The use of non-target species such as caddisflies in ecotoxicological research in lotic ecosystems is also discussed.
- How a Tourism City Responds to COVID-19: A CEE Perspective (Kraków Case Study)Publication . Kowalczyk-Anioł, Joanna; Grochowicz, Marek; Pawlusiński, RobertAcademic papers on the COVID-19 pandemic and tourism adopt the perspective of strengthening tourism resilience or recognize the ongoing crisis as an opportunity for reflection and the need to redefine tourism development strategies. This article examines these issues using the example of Kraków, a tourism city that, on the eve of the pandemic outbreak, was experiencing symptoms of overtourism. Using a case study approach, the authors illustrate the strategies applied at the city level, as well as the range of measures and actions used to support the tourism industry during the full pandemic year. The Kraków case shows that the pandemic time can be used to reorganize relations between local tourism stakeholders and to create a new formula for a tourism city in the so-called ‘new normal’. In addition, the exploratory case study allows for the formulation of research problems for further work on tourism cities responses to COVID-19. This can focus on a revision of the tourist offer and profile; the role of culture and the accompanying technology-facilitated innovations; the continuation of ‘being-a-tourist-in-your-own-city’, as promoted in the pandemic; tourists’ reactions to introduced changes; and shaping (new) relations between tourism stakeholders in the (post)pandemic city.
- Effects of cadmium and resource quality on freshwater detritus processing chains: a microcosm approach with two insect speciesPublication . Campos, Diana; Alves, Artur; Lemos, Marco F. L.; Correia, António; Soares, Amadeu M. V. M.; Pestana, João L. T.Detritus processing is vital for freshwater ecosystems that depend on the leaf litter from riparian vegetation and is mediated by microorganisms and aquatic invertebrates. Shredder invertebrates transform coarse particulate organic matter into fine particulate organic matter used as food by collector species. Direct and indirect effects of contaminants can impair detritus processing and thus affect the functioning of these ecosystems. Here, we assessed the combined effects of a toxic metal (cadmium) and resource quality (leaf species) on detritus processing and shredder-collector interactions. We considered two types of leaves, alder and eucalyptus that were microbially conditioned under different Cd concentrations in the laboratory. The microbial communities present on leaves were analyzed by Denaturing Gradient Gel Electrophoresis (DGGE), and we also measured microbial respiration rates. Sericostoma vittatum (a caddisfly shredder) and Chironomus riparius (a midge collector) were also exposed to Cd and allowed to consume the corresponding alder or eucalyptus leaves. We evaluated C. riparius growth and leaf mass loss in multispecies microcosms. Cadmium exposure affected leaf conditioning and fungal diversity on both leaf species, as assessed by DGGE. Cadmium exposure also affected the mass loss of alder leaves by reductions in detritivore feeding, and impaired C. riparius growth. Chironomus riparius consumed alder leaf discs in the absence of shredders, but S. vittatum appear to promote C. riparius growth in treatments containing eucalyptus. These results show that indirect effects of contaminants along detritus-processing chains can occur through effects on shredder-collector interactions such as facilitation but they also depend on the nutritional quality of detritus and on sensitivity and feeding plasticity of detritivore species.
- Human milk fat substitutes: Advances and constraints of enzyme‐catalyzed productionPublication . Ferreira-Dias, Suzana; Tecelão, CarlaThe production of triacylglycerols (TAGs) with similar structures to the human milk fat TAGs is only possible using sn-1,3 regioselective lipases as biocatalysts. The advances on the processes currently performed for the production of human milk fat substitutes (HMFS), namely the biocatalysts used, the best operation conditions, reactor types and operation modes, as well as the major drawbacks of these enzymatic systems, are addressed in this article.
- C2-Domain Abscisic Acid-Related Proteins Mediate the Interaction of PYR/PYL/RCAR Abscisic Acid Receptors with the Plasma Membrane and Regulate Abscisic Acid Sensitivity in ArabidopsisPublication . Rodriguez, Lesia; Gonzalez-Guzman, Miguel; Diaz, Maira; Rodrigues, Américo; Izquierdo-Garcia, Ana C.; Peirats-Llobet, Marta; Fernandez, Maria A.; Antoni, Regina; Fernandez, Daniel; Marquez, Jose A.; Mulet, Jose M.; Albert, Armando; Rodriguez, Pedro L.Membrane-delimited abscisic acid (ABA) signal transduction plays a critical role in early ABA signaling, but the molecular mechanisms linking core signaling components to the plasma membrane are unclear. We show that transient calcium-dependent interactions of PYR/PYL ABA receptors with membranes are mediated through a 10-member family of C2-domain ABA-related (CAR) proteins in Arabidopsis thaliana. Specifically, we found that PYL4 interacted in an ABA independent manner with CAR1 in both the plasma membrane and nucleus of plant cells. CAR1 belongs to a plant specific gene family encoding CAR1 to CAR10 proteins, and bimolecular fluorescence complementation and coimmunoprecipitation assays showed that PYL4-CAR1 as well as other PYR/PYL-CAR pairs interacted in plant cells. The crystal structure of CAR4 was solved, which revealed that, in addition to a classical calcium-dependent lipid binding C2 domain, a specific CAR signature is likely responsible for the interaction with PYR/PYL receptors and their recruitment to phospholipid vesicles. This interaction is relevant for PYR/PYL function and ABA signaling, since different car triple mutants affected in CAR1, CAR4, CAR5, andCAR9 genes showed reduced sensitivity to ABA in seedling establishment and root growth assays. In summary, we identified PYR/PYL-interacting partners that mediate a transient Ca2+-dependent interaction with phospholipid vesicles, which affects PYR/PYL subcellular localization and positively regulates ABA signaling.
- Topic Prominence of Tourism and Hospitality Scientific Research: The Case of SwitzerlandPublication . Cardoso, Lucília; Soliman, Mohammad; Araújo-Vila, Noelia; Almeida, Giovana Goretti Feijó deTopic prominence is regarded as a recent indicator that reveals the present momentum of a certain topic by considering the citations, views, and CiteScore thresholds. Topic prominence has been examined in prior research within different contexts, however, there is no known study exploring this trend within tourism and hospitality literature. Therefore, this study aims to analyse and map the topic prominence of Tourism, Leisure and Hospitality Management (TLHM) research by focusing on Switzerland as a case study. The collected data included 337 articles published in 46 journals indexed in Scopus under the subject category of TLHM. The findings concluded that topic prominence is an important indicator for measuring scientific research productivity, including peer-reviewed articles. More particularly, it is revealed that the investigation of topic prominence provides an overall clearer picture of Swiss TLHM research. This study contributes to tourism studies by discussing the usage of the topic prominence metric for tourism and hospitality publications. It also presents practical implications for tourism research managers and researchers by providing solid insights into funded research, scholars’ and institutions’ performance, and momentum of topics associated with the Swiss TLHM articles.
- The golden mackerel: first report of a xanthic Mediterranean horse mackerel Trachurus mediterraneus (Steindachner, 1868) from Sines, PortugalPublication . Vasco-Rodrigues, Nuno; Santos, Simão; Espírito-Santo, Cristina; Almada, FredericoIn this study, a single xanthic case of the Mediterranean horse mackerel Trachurus mediterraneus is reported. The individual, with a total lenght (TL) of 306 mm, was captured off Sines (Portugal) in March 2018, by a local fishing boat, using a seine net. This represents the first record of xanthism for this species and for any species of mackerel. The specimen is described here and compared with those of normal pigmentation. Considerations about the paucity of records for this or similar species are presented here, and the possibility of this condition being more frequent than previously thought is discussed.