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- Selective Inhibition of Clade A Phosphatases Type 2C by PYR/PYL/RCAR Abscisic Acid ReceptorsPublication . Antoni, Regina; Gonzalez-Guzman, Miguel; Rodriguez, Lesia; Rodrigues, Américo; Pizzio, Gaston A.; Rodriguez, Pedro L.Abstract Clade A protein phosphatases type 2C (PP2Cs) are negative regulators of abscisic acid (ABA) signaling that are inhibited in an ABA-dependent manner by PYRABACTIN RESISTANCE1 (PYR1)/PYR1-LIKE (PYL)/REGULATORY COMPONENTS OF ABA RECEPTORS (RCAR) intracellular receptors. We provide genetic evidence that a previously uncharacterized member of this PP2C family in Arabidopsis (Arabidopsis thaliana), At5g59220, is a negative regulator of osmotic stress and ABA signaling and that this function was only apparent when double loss-of-function mutants with pp2ca-1/ahg3 were generated. At5g59220-green fluorescent protein and its close relative PP2CA-green fluorescent protein showed a predominant nuclear localization; however, hemagglutinin-tagged versions were also localized to cytosol and microsomal pellets. At5g59220 was selectively inhibited by some PYR/PYL ABA receptors, and close relatives of this PP2C, such as PP2CA/ABA-HYPERSENSITIVE GERMINATION3 (AHG3) and AHG1, showed a contrasting sensitivity to PYR/PYL inhibition. Interestingly, AHG1 was resistant to inhibition by the PYR/PYL receptors tested, which suggests that this seed-specific phosphatase is still able to regulate ABA signaling in the presence of ABA and PYR/PYL receptors and therefore to control the highly active ABA signaling pathway that operates during seed development. Moreover, the differential sensitivity of the phosphatases At5g59220 and PP2CA to inhibition by ABA receptors reveals a functional specialization of PYR/PYL ABA receptors to preferentially inhibit certain PP2Cs.
- Perceptions about Tourism and Tourists in Historic Neighborhoods: The Case of AlfamaPublication . Madeira, Arlindo; Palrão, Teresa; Mendes, Alexandra Sofia; López-Morales, ErnestoTourism makes destinations adapt to receive those who visit them, with a great impact among traditional residents. Overtourism affects picturesque places, and these areas end up losing their authenticity, submitting themselves to the consumption needs of tourists. Neighborhoods’ traditional residents also see their routine completely changed due to the different habits of tourists, and displacement rates rise. This study aims to understand how local people perceive tourism in Alfama, one of the most unique and tourist-oriented neighborhoods of Lisbon. Our study involves a questionnaire to old long-term residents and content analysis of their responses. We used Leximancer software to create categories of analysis depending on frequency of mentions and the way themes are related. Our interviewees testified that overtourism in Alfama generates perceptions that range from a generalized acceptance for the benefits that an improved safety associated to an increased street-life and a cleaner neighborhood generate, and on the other hand the grievance for the loss of a pre-existing community. We also conclude that the benefits of tourist-led gentrification are relevant for the gentrification analysis because they show the contradictions that the remaining residential community experience as tourist-led gentrification unfolds.
- Marine Natural Products as Anticancer AgentsPublication . Alves, Celso; Diederich, MarcCancer remains one of the major threats to human health and one of the deadliest diseases worldwide [1]. Therapy failure and consequent cancer relapse are the main factors contributing to high cancer mortality, making it crucial to find and develop new therapeutic options. Over the last few decades, natural products became one of the key drivers in the drug development of innovative cancer treatments [2]. In opposition to drug development from terrestrial resources, the marine environment only recently emerged as a prolific source of unparalleled structurally active metabolites [3]. Due to their excellent scaffold diversity, structural complexity, and ability to act on multiple cell signaling networks involved in carcinogenesis, marine natural products are ideal candidates to inspire the development of novel anticancer medicines [4,5].
- Sustainability Communication in Rural Tourism: Website Content Analysis, in Viseu Dão Lafões Region (Portugal)Publication . Pato, Maria Lúcia; Duque, Ana SofiaIn the last few years, the relationship between tourism and sustainability has been con-solidated. In the context of rural tourism, this connection is even stronger given the environmental specificities and the natural framework of this type of tourism. To achieve sustainability behaviors, it is crucial that rural tourism lodgings communicate their essence, as well the products and experiences available for tourists. This because it is a common practice for visitors to look for more information on the internet about where they will be staying, before booking their tourist experience. The main objective of this study is the analysis of the information provided by rural tourism lodgings, through their websites, regarding sustainability issues. The territory selected for the development of this study is the Portuguese Viseu Dão Lafões Region, located in the center of Portugal. Based on other studies, the methodology includes a content analysis, conducted on 39 rural tourism lodging websites. The results show that some improvements are needed, to clarify and emphasize the message about sustainable practices, in these rural lodgings. Some practical recommendations are provided, that can be adapted to these rural tourism lodgings, or others.
- Entrepreneurship in the sustainable tourism sector. the case of tour operators in LithuaniaPublication . Navickiene, Regina; Fominiene, Vilija Bite; Dias, FranciscoIn the following article, the main objective is to analyse the phenomenon of the entrepreneurship and its significance for the sustainable business including the business of tourism. Under the basis of the completed analysis of literature, there is presented the manifestation model of entrepreneurship in the sustainable tourism highlighting the entrepreneur and his/her quality constituents. During the empirical research, following the example of tour operators' case, it is clarified if there is manifested entrepreneurship in the tourism sector. The conclusions of the completed research enable to make the statement that the managers of the researched Lithuanian companies, which carry out the function of tour operators, claim to possess all the qualities characteristic for the entrepreneurs. Thus, it can be understood that the manager's as entrepreneur's presence in the organization provides necessary conditions for the manifestation of entrepreneurship in the following organization and sustainable tourism development in Lithuania.
- Sensitivity of the sea snail Gibbula umbilicalis to mercury exposure – Linking endpoints from different biological organization levelsPublication . Cabecinhas, Adriana S.; Novais, Sara C.; Santos, Sílvia C.; Rodrigues, Andreia C.M.; Pestana, João L.T.; Soares, Amadeu M.V.M.; Lemos, Marco F.L.Mercury contamination is a common phenomenon in the marine environment and for this reason it is important to develop cost-effective and relevant tools to assess its toxic effects on a number of different species. To evaluate the possible effects of Hg in the sea snail Gibbula umbilicalis, animals were exposed to increasing concentrations of the contaminant in the ionic form for 96h. After this exposure period, mortality, feeding and flipping behavior, the activity of the biomarkers glutathione S-transferase, superoxide dismutase, catalase, lactate dehydrogenase and cholinesterase, the levels of lipid peroxidation and cellular energy allocation were measured. After 96h of exposure to the highest Hg concentration (≈LC20), there was a significant inhibition of the cholinesterase activity as well as impairment in the flipping behavior and post-exposure feeding of the snails. Cholinesterase inhibition was correlated with the impairment of behavioral responses also caused by exposure to Hg. These endpoints, including the novel flipping test, revealed sensitivity to Hg and might be used as relevant early warning indicators of prospective effects at higher biological organization levels, making these parameters potential tools for environmental risk assessment. The proposed test species showed sensitivity to Hg and proved to be a suitable and resourceful species to be used in ecotoxicological testing to assess effects of other contaminants in marine ecosystems.
- A model of graduates׳ satisfaction and loyalty in tourism higher education: The role of employabilityPublication . Eurico, Sofia Teixeira; Silva, João Albino Matos da; Valle, Patrícia Oom doThis study seeks to examine the role of employability in the process of satisfaction and loyalty formation towards higher education institutions (HEI), when considering tourism graduates. It explores how employability has been approached within HEIs and how graduates satisfaction and loyalty have been assessed in higher education. A structural equation model, including the employability construct, is proposed and validated, and the results confirm that the HEIs image is strongly influenced by employability. These results might represent a valuable source of information for HEIs in the process of finding the balance between the service provided and the needs of the stakeholders.
- Trematode fauna of Hydrobia ulvae (Gastropoda: Prosobranchia) in a eutrophic temperate estuaryPublication . Bordalo, M. D.; Ferreira, Susana; Jensen, K.T.; Pardal, M.A.Digenean trematodes infecting the mud snail Hydrobia ulvae were studied at two key sites of the Mondego Estuary (Portugal), from January 1993 to September 1995: a mud flat covered by the seagrass Zostera noltii, and a bare sand flat where seasonal macroalgal blooms occurred as a result of eutrophication. Digeneans belonging to Microphallidae, Notocotylidae, Haploporidae and Heterophyidae were recorded in snails from both sites whereas representatives from Echinostomatidae were only found in snails from the seagrass bed. The density of infected snails was higher at the seagrass bed than at the eutrophic area partly reflecting the difference in population structure of H. ulvae between sites. The Zostera noltii bed supports an abundant and well-structured mud snail population, with all size-classes represented, in contrast to a less abundant and juvenile dominated population in the eutrophic area. In the Z. noltii bed no clear seasonal and interannual patterns emerged in the infection densities. In the eutrophic area, the density of infected individuals increased in the presence of algae, and decreased during the occurrence of occasional flood events. Small scale spatial and temporal patterns in the prevalence of digenean trematodes in mud snails were therefore demonstrated within the Mondego Estuary that has experienced a mixture of anthropogenic impact and climate instability.
- Effects of imidacloprid exposure on Chironomus riparius Meigen larvae: Linking acetylcholinesterase activity to behaviourPublication . Azevedo-Pereira, H.M.V.S.; Lemos, M. F. L.; Soares, A.M.V.M.Imidacloprid (IMI) is an insecticide that interferes with the transmission of stimuli in the nervous system of insects. It is neurotoxic by mimicking nicotine through its binding to the nicotinic acetylcholine receptor. In this work, experiments comprising 96 h exposure followed by 48 h in clean medium were conducted to evaluate the toxicity of IMI to Chironomus riparius and its potential recovery. Behavioural parameters and AChE activity were assessed. After 96 h exposure to IMI, AChE activity, and the behaviour parameters ventilation and locomotion were reduced. There were no signs of recovery after removal to clean water for 48 h. Ventilation behaviour was the most sensitive parameter and the one with the highest correlation to AChE activity. Despite the possibility that IMI might be having an indirect effect on AChE activity, the behavioural endpoint showed a higher sensitivity than the biochemical response itself. This work highlights the importance of linking parameters with ecological relevance at individual level (behavioural parameters) with biochemical responses, to unravel xenobiotics mode of action.
- Optimisation of Alginate Extraction and Characterisation of Polysaccharides from Brown Seaweed from the Portuguese CoastPublication . Mendes, Joana Corrêa; Valente, Joana F. A.; Sousa, Fani; Bernardino, Raul; Bernardino, Susana; Afonso, Clélia; Chagas, BárbaraAlginate is a widely used and versatile biopolymer with an ever-expanding range of applications in the pharmaceutical and biomedical industries. This highlights the importance of developing sustainable and renewable production sources. Conventional extraction methods, although effective, are often energy-intensive and rely on harsh chemicals. In this context, brown algae are a promising alternative due to their abundance and renewability. This study investigated the potential of Saccorhiza polyschides and Sargassum muticum as sources of sodium alginate (SA), thus optimising an extraction process that combines acid treatment with an alkaline step. The extracted biopolymers were characterised using FTIR, H-NMR, STA, SEM/EDX, viscosity measurements, dynamic light scattering, and spectrophotometric assays of residual polyphenols and proteins. The optimised extraction conditions produced yields above 20% of high-purity alginate. When compared with commercial SA, the extracted materials showed comparable quality while relying on a simplified, solvent-reduced protocol that improves process efficiency and reduces the environmental impact. These results demonstrate that S. polyschides and S. muticum are promising, locally available sources of high-quality sodium alginate, and that industrially relevant yields (>20%) can be achieved through an environmentally conscious two-step extraction process.