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- Main challenges, trends and opportunities for wine tourism in PortugalPublication . Ramos, Paulo; Santos, Vasco Ribeiro; CASTANHEIRA ALMEIDA, NUNO MIGUELPurpose – This paper aims to define the boundaries of wine tourism to identify the main challenges, trends and opportunities of wine tourism in Portugal, providing some critical recommendations for those operating in this sector. Design/methodology/approach – The paper draws on a literature review and content analysis of prior and ongoing work. Findings – The main challenges, trends and opportunities for the wine tourism industry in Portugal are identified, as well as suggestions and practical recommendations/contributions for managers, stakeholders, players and marketers. The paper concludes with some key points that could form the basis of a strategic agenda for future action. Originality/value – Based on the reviewed literature, some benchmarks for the wine tourism industry in Portugal were developed.
- Effects of dietary Gracilaria sp. and Alaria sp. supplementation on growth performance, metabolic rates and health in meagre (Argyrosomus regius) subjected to pathogen infectionPublication . Peixoto, Maria João; Salas-Leitón, Emílio; Brito, Francisca; Pereira, Luís Ferreira; Svendsen, Jon C.; Baptista, Teresa; Pereira, Rui; Abreu, Helena; Reis, Pedro Alexandre; Gonçalves, José Fernando Magalhães; Ozório, Rodrigo Otávio de AlmeidaEffects of dietary seaweed supplementation on basal physiology and health biomarkers were assessed in meagre (Argyrosomus regius) subjected to bacterial infection, using Photobacterium damselae subsp. Piscicida (Phdp) as the etiologic agent. Three test diets were prepared by supplementing a basal control formulation (44 % protein, 16 % lipid, 22 kJ g−1 energy) with 0 % seaweed (control), 5 % Gracilaria sp. or 5 % Alaria sp. During the growth trial, 180 fish (39.70 ± 0.33 g) were daily fed for 69 days with the experimental diets. After the growth trial, 60 fish from each dietary treatment were divided into two groups, infected and non-infected. The infected group was injected intraperitoneally with a saline solution (HBSS) with 2.91 x 103 CFU Phdp g−1 fish, whereas the non-infected group was injected with HBSS without Phdp. Dietary seaweed supplementation did not affect fish growth performance. Standard and routine metabolic rates, and aerobic metabolic scope did not vary significantly among dietary treatments. Conversely, maximum metabolic rate was significantly higher in fish fed Alaria sp. diet when compared to control group. Non-infected fish had higher hematocrit levels than the infected group, regardless of diet. Lactate levels were significantly higher in fish fed Alaria sp. diet when compared to control, with no interaction between diet and infection. Lipid peroxidation was significantly higher in fish fed control diet than supplemented diets. Infected groups had lower antioxidant enzymes activities when compared to non-infected. An interaction between infection and diet was found for glutathione peroxidase and reduced glutathione activities. The current study suggests that dietary seaweed supplementation modulates metabolic rates and biomarker responses in meagre, which may confer advantages in coping with biotic stressors.
- Detection of QnrB54 and Its Novel Genetic Context in Citrobacter freundii Isolated from a Clinical CasePublication . Campos, Maria Jorge; Palomo, Gonzalo; Hormeño, Lorena; Rodrigues, Américo; Sánchez-Benito, Rosario; Píriz, Segundo; Quesada, AlbertoLETTER Quinolone resistance in Enterobacteriaceae is mediated by mutations in the quinolone resistance-determining regions (QRDR) of topoisomerase genes and/or by plasmid-mediated quinolone resistance determinants (PMQR) such as the qnr genes encoding pentapeptide repeat proteins (1). The qnrB family is represented by 80 different alleles (http://www.lahey.org/qnrStudies/); most of them originated from Citrobacter strains and spread to other Enterobacteriaceae species (2). This work describes the identification of a new allele of the quinolone resistance protein QnrB, QnrB54, in a human clinical isolate of Citrobacter freundii detected in Spain.
- Asparagopsis armata and Sphaerococcus coronopifolius as a natural source of antimicrobial compoundsPublication . Pinteus, Susete; Alves, Celso; Monteiro, Hugo; Ernesto Araújo; Horta, André; Pedrosa, RuiMethanol, n-hexane and dichloromethane extracts of twelve marine macro-algae (Rhodophyta, Chlorophyta and Heterokontophyta divisions) from Peniche coast (Portugal) were evaluated for their antibacterial and antifungal activity. The antibacterial activity was evaluated by disc diffusion method against Bacillus subtilis (gram positive bacteria) and Escherichia coli (gram negative bacteria). Saccharomyces cerevisiae was used as a model for the antifungal activity by evaluating the growth inhibitory activity of the extracts. The high antibacterial activity was obtained by the Asparagopsis armata methanolic extract (10 mm–0.1 mg/disc), followed by the Sphaerococcus coronopifoliusn-hexane extract (8 mm–0.1 mg/disc), and the Asparagopsis armata dichloromethane extract (12 mm–0.3 mg/disc) against Bacillus subtilis. There were no positive results against Escherichia coli. Sphaerococcus coronopifolius revealed high antifungal potential for n-hexane (IC50 = 40.2 µg/ml), dichloromethane (IC50 = 78.9 µg/ml) and methanolic (IC50 = 55.18 µg/ml) extracts against Saccharomyces cerevisiae growth. The antifungal potency of the Sphaerococcus coronopifolius extracts was similar with the standard amphotericin B. Asparagopsis armata and Sphaerococcus coronopifolius reveal to be interesting sources of natural compounds with antimicrobial properties. © 2015, Springer Science+Business Media Dordrecht.
- Thermal stress effects on energy resource allocation and oxygen consumption rate in the juvenile sea cucumber, Holothuria scabra (Jaeger, 1833)Publication . Kühnhold, Holger; Kamyab, Elham; Novais, Sara; Indriana, Lisa; Kunzmann, Andreas; Slater, Matthew; Lemos, MarcoWater temperature is a key factor in aquaculture production of the commercially valuable sea cucumber Holothuria scabra. Knowledge is scarce about actual energetic costs that can be associated with internal acclimatization processes as a response to thermal extremes. In the present study changes in cellular energy allocation, oxygen consumption rate and energy related enzymes' activity (IDH and LDH) were measured in juvenile H. scabra, held at different temperatures: 21, 27 and 33 °C. The results showed that the steady temperature change (1 °C/day) to both temperature treatments, until reaching the testing temperatures (day 0), clearly affected cellular energy consumption and available energy reserves, measured in the respiratory tree and muscle tissue, respectively. However, 15 and 30 days after acclimation, the initial differences in cellular energy allocation between treatments decreased. In contrast to the variations measured in cellular energy allocation, oxygen consumption was highest at 33 °C and lowest at 21 °C at all three measurement times. Moreover, a significant positive correlation between oxygen consumption rate and temperature was detected at day 15 and day 30. Likewise, a shift from anaerobic to aerobic energy metabolism, indicated by changes in LDH and IDH activities, was observed in the animals from the warm temperature treatment. Results imply that juvenile H. scabra were able to recover from initial disturbances in energy balance, caused by the incremental temperature change of ±6 °C. Over the experimental period of 30 days, elevated temperature did however, lead to a metabolic shift andmore efficient energy turnover, indicated by changes in oxygen consumption rate, LDH and IDH. The synergy of cellular energy allocation and oxygen consumption proved to be a viable indicator to assess the capability of sea cucumbers like H. scabra to cope with extreme temperature conditions. Surprisingly, juvenile H. scabra were able to sustain their energy balance and oxygen consumption rate within the homeostatic range, even at 33 °C. Thus, we assume that rearing temperatures of 33 °C might be possible, which could improve aquaculture production of H. scabra. However, further research is required to understand the mechanisms and effects of acclimation under aquaculture conditions. Statement of relevance: The sea cucumber H. scabra is considered a promising aquaculture candidate in the tropics. The commercial interest in H. scabra has led to a great number of attempts to culture this species e.g. in Madagascar, Tanzania, India and Indonesia, where the farming of this species also showed a great potential to increase the livelihood of the local community. Although, considerable research effort has been put into the advancement of the production cycle, fundamental knowledge, e.g. on physiological adjustments due to suboptimal rearing conditions, remains scarce for H. scabra.Water temperature has been identified as crucial factor, determining production efficiency. In our manuscriptwe introduce an innovative approach, for the assessment of shifts in the energy budget as well as in metabolic pathways, to detect thermal stress in juvenile H. scabra. Our results show that the combined application of cellular energy allocation (CEA) and measurement of the oxygen consumption rate (OCR) as well as the activity of two metabolic key enzymes: iso-citrate dehydrogenase (IDH) and lactate dehydrogenase (LDH), is a strong analytical tool to evaluatewhole animal homeostasis under thermal extremes. To our knowledge this is the first study inwhich the method of CEAwas optimized for the application on isolatedmuscle and respiratory tree tissue of a sea cucumber, like H. scabra.Hence, our results provide original insights into the thermal acclimation physiology of H. scabra, which provides crucial knowledge for setting up optimal culture conditions for this highly valuable aquaculture candidate. Moreover, our results show that juvenile H. scabra were strongly affected by rapid temperature changes, exhibiting distinct differences in metabolic adjustments as response to short-term cold and warm acclimation, but were able to restore homeostatic conditions at constant cold and warm temperature extremes. Concerning aquaculture practices, these findings imply that CEA might be a good condition indicator to evaluate the overall metabolic status in sea cucumbers. Moreover, rapid temperature fluctuations seem to provoke much higher energetic costs in juvenile H. scabra than constant extreme temperature conditions, which is important to consider in daily management practices. The OCR revealed an enhanced metabolism at warmer temperature conditions, throughout the entire experimental period. Likewise, the warm exposed animals were shifting their energy turnover from a more anaerobic to amore aerobic state, indicated by changes in LDH and IDH activities, and showed increased foraging activity at all times. The combined outcome of CEA, OCR and activities of energymetabolismrelated enzymes indicates, that the increased metabolic activity in juvenile H. scabra, as response to warmer temperature, was well within the homeostatic range. Thus, contrary to our expectations, a rearing temperature of up to 33 °C might presumably be favourable for the aquaculture of H. scabra.
- POLÍTICAS LOCAIS E IMPACTOS NA CONCEÇÃO DA EXPERIÊNCIA TURÍSTICA EM ESPAÇOS URBANOS – OS CASOS DO BAIRRO ALTO E DA MOURARIA, LISBOAPublication . Xavier, António José Tavares da Costa; Almeida, António Sérgio Araújo deA reabilitação urbana do património arquitetónico e monumental em bairros históricos tende a propiciar a disputa na utilização/apropriação dos “novos” espaços daí resultantes, não só por novos moradores, normalmente de classes sociais mais abastadas, mas também por novos comerciantes, mais especializados em contextos empresariais. Surgem, assim, novos espaços de residência, lazer, entretenimento e cultura, entre outros. Apurar contributos locais para que bairros típicos proporcionassem experiências locais e turísticas diferenciadas na perspetiva da fidedignidade às origens foi um dos grandes objetivos deste trabalho. Paradoxalmente, conforme observado na cidade de Lisboa e após uma investigação realizada em 2014 e 2015, a mesma governação local de reabilitação urbana suscita ambivalências a vários níveis. Por um lado, promovendo identidades e valores que caracterizam objetivamente a Tradição e a História num regime de reciprocidade com os habitantes locais, e, por outro lado, transformando espaços onde os valores culturais se assumem numa função comercial sem correspondência nas expectativas das gentes locais nem coerência com a autenticidade (resultante dos valores identitários) dos respetivos espaços. Enquanto no Bairro Alto permitiuse aos investidores a decisão na apropriação e utilização do espaço, na Mouraria, registou-se um processo de governação integrada com a mobilização da população residente e forças ativas do bairro. No primeiro caso, surgiram conflitos entre novos e velhos utilizadores do bairro, assumindo-se a oferta turística como espaço de animação noturna centrada num espaço público de boémia, no consumo de álcool e num ambiente de festa permanente No segundo caso, geraram-se sinergias propiciadoras de uma reabilitação urbana defensora da mobilização das estruturas identitárias do bairro, promovendo estilos de vida tradicionais e resgatando o seu imaginário coletivo assente nos seus próprios sistemas de valores. Na Mouraria, observa-se um Turismo comunitário, envolvendo gentes locais, que, apropriando-se do seu espaço turístico, o projetam no pressuposto de consubstanciar objetivamente o seu património numa experiência turística diferenciada.
- Trabalho sem fronteiras: Perspetivas sobre os serviços domésticos e a prestação de cuidadosPublication . Dias, Nuno; Brasão, Inês; Abrantes, ManuelA apresentação deste dossier resulta do encontro de vontades de três pessoas que têm investigado o universo dos serviços domésticos a partir de perspetivas diferenciadas, complementares, mas, por vezes, pouco comunicantes. Os processos de feminização dos movimentos migratórios e do mercado de trabalho das últimas décadas têm sido reconhecidos largamente pela literatura, em alguns casos como parte integrante desses movimentos desde a sua origem. A globalização da economia capitalista e o consequente movimento perpétuo de circulação de forças de criação e de destruição de trabalho beneficiaram da participação, nesse movimento, das mulheres e da sua fuga, enquanto resistência, à «dominação masculina». Todavia, apesar da natureza estruturante destas dinâmicas, as narrativas mais influentes sobre o mercado de trabalho e as suas disposições futuras tendem a menorizar um amplo conjunto de protagonistas e de sectores de atividade.
- Discriminative influence of persistent organic pollutants on nesting green sea turtles through genotoxicity, oxidative stress and reproductive related markersPublication . Morão, Inês; Muñoz-Arnanz, Juan; Simões, Tiago; Bartalini, Alice; Vieira, Sara; Ferreira-Airaud, Betânia; Caliani, Ilaria; Noi, Agata Di; Casini, Silvia; Fossi, Maria Cristina; Jiménez, Begoña; Lemos, Marco; Novais, SaraPersistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochloride pesticides (OCPs) affect biodiversity by bioaccumulating through food webs, impacting marine organisms like endangered sea turtles. This study represents the first evaluation of these contaminants in sea turtles nesting in São Tomé and Príncipe. The main goal was to evaluate PCBs, PBDEs and OCPs levels in sea turtles' blood and investigate their potential effects on erythrocytes’ nuclear abnormalities (ENAs) and oxidative stress and reproduction-related gene expression. The relative mean abundance for contaminants was ΣPCBs > ΣOCPs > ΣPBDEs. Contaminants such as PCB-28, PCB-138, PCB-153, PCB-180 and p,p’-DDE were associated with ENAs, suggesting potential genetic instability and cellular disruption. PCB-126, PBDE-100, and o,p’-DDD correlated with antioxidant and detoxification genes (glrx3, gst, txnip, txnrd2, and gclc), suggesting oxidative stress responses. The reproduction-related gene est17 was correlated with α and β-HCH, potentially affecting ovary development. Correlations between ace2 and various PCBs, PBDEs, and o,p'-DDD suggest disruptions in follicular development and egg transport. Embryo development genes (hoxA1 and tuba1) were associated with PBDE-154, PBDE100 and o,p’-DDD, suggesting possible embryonic alterations. These findings highlight the impacts of POPs on nesting female green turtles in São Tomé, threatening this endangered population.
- From Form to Function: The Anatomy, Ecology, and Biotechnological Promise of the False-Kelp Saccorhiza polyschidesPublication . Afonso, Clélia; Mouga, TeresaSaccorhiza polyschides is a fast-growing pioneer and opportunistic canopy-forming false-kelp belonging to the order Phyllariaceae (Ochrophyta, Phaeophyceae). The species plays a pivotal ecological role in temperate marine ecosystems and exhibits promising potential for diverse biotechnological applications. The species, however, is under growing pressure from anthropogenic disturbance. This review synthesises current knowledge regarding the biology and geographic distribution of the species, with particular emphasis on its distinctive morphology and ultrastructural features. The species’ complex life cycle and marked seasonal productivity are examined concerning environmental variables. Furthermore, we explore the ecological interactions of the species, including its role as a habitat-forming species and its responses to anthropogenic stressors such as climate change and habitat degradation. Special attention is given to the state of knowledge regarding the bioactive compounds and associated bioactivities of S. polyschides. This includes a detailed examination of the species’ phytochemical constituents, extraction and fractionation strategies, as well as in vitro and in vivo bioactivities, and potential biotechnological applications. By integrating findings from recent literature and identifying methodological and knowledge gaps, this paper seeks to provide a comprehensive understanding of S. polyschides as an emergent marine bioresource and to propose directions for future research and sustainable valorisation.
- Endocrine and physiological effects of linuron and S-metolachlor in zebrafish developing embryosPublication . Quintaneiro, C.; Patrício, D.; Novais, Sara; Soares, A.M.V.M.; Monteiro, M.S.Evaluation of the effects of linuron and S-metolachlor on apical, biochemical and transcriptional endpoints in zebrafish (Danio rerio) early life stages was the main purpose of this work. Embryos were exposed for 96h to a range of concentrations of each herbicide to determine lethal and sub-lethal effects on apical (e.g. malformations, hatching) and biochemical parameters (cholinesterase, ChE; catalase, CAT; glutathione S-transferase, GST; lipid peroxidation, LPO and lactate dehydrogenase, LDH). To evaluate endocrine disruption effects, embryos were exposed during 96h to 0.88mg/L linuron and 9.66mg/L S-metolachlor, isolated or in binary mixture. Expression of a suite of genes involved in HPT, HPG and HPA-axis was then assessed. Highest concentration of linuron (5.0mg/L) decreased hatching rate to 5% and 70.0mg/L S-metolachlor completely inhibited hatching, about 100%. Both herbicides impaired development by inducing several malformations (100% in 5.0mg/L linuron and 70.0mg/L S-metolachlor). Linuron only affected GST and CAT at concentrations of 0.25 and 0.0025mg/L, respectively. S-metolachlor induced GST (to 256%), inhibited ChE (to 61%) and LDH (to 60%) and reduced LPO levels (to 63%). Linuron isolated treatment seems to have an estrogenic mode of action due to the observed induction of vtg1. Exposure to S-metolachlor seems to interfere with steroidogenesis and with HPT and HPA-axis, since it has inhibited cyp19a2, TSHβ and CRH gene expression. In addition to vtg1 induction and CRH inhibition, herbicide combination also induced sox9b that has a role in regulation of sexual development in zebrafish. This study pointed out adverse effects of linuron and S-metolachlor, namely impairment of neurotransmission and energy production, induction of steroidogenesis, and interference with HPT and HPA-axis. These results contributed to elucidate modes of action of linuron and S-metolachlor in zebrafish embryo model. Furthermore, gene expression patterns obtained are indicative of endocrine disruption action of these herbicides.