128 research outputs found

    Unveiling biological activities of marine fungi: the effect of sea salt

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    There is an urgent need for new substances to overcome current challenges in the health sciences. Marine fungi are known producers of numerous compounds, but the manipulation of growth conditions for optimal compound production can be laborious and time-consuming. In Portugal, despite its very long coastline, there are only a few studies on marine fungi. From a collection of Portuguese marine fungi, we screened for antimicrobial, antioxidant, enzymatic, and cytotoxic activities. Mycelia aqueous extracts, obtained by high pressure-assisted extraction, and methanolic extracts of culture media showed high antioxidant, antimicrobial, and cytotoxic activities. The mycelium extracts of Cladosporium rubrum showed higher antioxidant potential compared to extracts from other fungi. Mycelia and culture media extracts of Aspergillus affinis and Penicillium lusitanum inhibited the growth of Staphylococcus aureus, Kocuria rhizophila, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa, including multiresistant strains. Penicillium lusitanum and Trichoderma aestuarinum inhibited the growth of clinical strains of Candida albicans, C. glabrata, C. parapsilosis, and C. tropicalis. All extracts from culture media were cytotoxic to Vero cells. Sea salt induced alterations in the mycelium's chemical composition, leading to different activity profiles.info:eu-repo/semantics/publishedVersio

    Professional Training in Beekeeping: A Cross-Country Survey to Identify Learning Opportunities

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    first_pagesettingsOrder Article Reprints Open AccessArticle Professional Training in Beekeeping: A Cross-Country Survey to Identify Learning Opportunities by Raquel P. F. Guiné 1ORCID,Jorge Oliveira 1ORCID,Catarina Coelho 1,2,*ORCID,Daniela Teixeira Costa 1,Paula Correia 1ORCID,Helena Esteves Correia 1ORCID,Bjørn Dahle 3,Melissa Oddie 3,Risto Raimets 4,Reet Karise 4ORCID,Luis Tourino 5,Salvatore Basile 6,Emilio Buonomo 6,Ivan Stefanic 7 andCristina A. Costa 1ORCID 1 CERNAS Research Centre, Polytechnic Institute of Viseu, 3504-510 Viseu, Portugal 2 CECAV, Animal and Veterinary Research Center, University of Trás-os-Montes e Alto Douro, Quinta de Prados, Apartado 1013, 5000-801 Vila Real, Portugal 3 Norwegian Beekeepers Association, 2040 Kløfta, Norway 4 Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 51014 Tartu, Estonia 5 Eosa Estrategia y Organización SA, 36202 Vigo, Spain 6 Bio-Distretto Cilento, 84052 Salerno, Italy 7 Tera Tehnopolis, 31000 Osijek, Croatia * Author to whom correspondence should be addressed. Sustainability 2023, 15(11), 8953; https://doi.org/10.3390/su15118953 Received: 21 April 2023 / Revised: 24 May 2023 / Accepted: 31 May 2023 / Published: 1 June 2023 (This article belongs to the Special Issue Prospects Challenges and Sustainability of the Agri-Food Supply Chain in the New Global Economy II) Download Browse Figures Review Reports Versions Notes Abstract Habitat loss, climate change, and other environmental degradations pose severe challenges to beekeepers. Therefore, this sector needs to rely on updated information so that the intervening actors can deal with the problems. In this context, and assuming that professional training can greatly help those acting in the beekeeping sector, this work intended to investigate the gaps in the updated knowledge of beekeepers and how these can be filled through lifelong learning. The research was conducted in seven European countries (Croatia, Estonia, Finland, Italy, Norway, Portugal, and Spain). The data were collected through a questionnaire survey translated into the native languages of all participating countries. The results revealed that the topics of highest interest are apiary health and pest control and the management of the colonies throughout the year. The beekeepers update their knowledge through family, complemented by professional training, with participants preferring in-person courses as well as, in the workplace or in internships. The learning methodologies they consider most useful are project-based learning and learning through gamification. The videos and paper books or manuals are particularly valued as learning materials, and practical exercises are considered the most helpful assessment format. Finally, considering the effect of sociodemographic variables on the learning experiences and preferences of beekeeping actors, it was observed that the country was the most influential of the variables under study. In conclusion, this work revealed valuable information that should be used to design professional training actions to help the professionals in the beekeeping sector enhance their competencies and be better prepared to manage their activities successfully.info:eu-repo/semantics/publishedVersio

    Absence of diabetic retinopathy in a patient who has had diabetes mellitus for 69 years, and inadequate glycemic control: case presentation

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    The main risk factors for the development and progression of diabetic retinopathy (DR) are chronic hyperglycemia, disease duration and systemic blood pressure. So far chronic hyperglycemia is the strongest evidence concerning the risk of developing DR. However there are some patients with poor metabolic control who never develop this diabetic complication. We present a case of a 73-year-old woman with type 1 diabetes mellitus, diagnosed 69 years ago. The patient is 73 years old, with no evidence of DR, despite poor glycemic control and several risk factors for DR. This case suggests the presence of a possible protection factor, which could be genetic

    Can stigma become a resource? The mobilisation of aesthetic–corporal capital by female immigrant entrepreneurs from Brazil

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    The proportion and visibility of Brazilian women and particularly the specific images of Brazil and Brazilians in the Portuguese imaginary have contributed to the construction of new versions of stigma and stereotypes surrounding them. Mainstream images of Brazilian women have incorporated prejudices about the sensuality of Creole women who are reminiscent of the Portuguese colonial imaginary. Starting from this stigmatised image, we show how Brazilian women entrepreneurs in the ‘beauty’ business filière reinterpret and mobilise this perceived negative image, transforming it into an added value associated with an ‘aesthetic’ Brazilian body culture. This idea of ‘body’ aesthetics becomes a business resource transformed into aesthetic– corporal capital, a key component of the Brazilian beauty business filière. Empirically, this research is based on qualitative elements, in particular 25 interviews with Brazilian women entrepreneurs of the beauty filière working in Portugal, collected for the project BELTS-W (Brazilian Entrepreneurial Links and Transnational Strategies – Women).This article is an output of the Foundation for Science and Technology (FCT) sponsored project PIHM/GC/0111/2008 and Brazilian Entrepreneurial Links and Transnational Strategies-Women (BELTS-W)

    Mineralogical evolution of cement pastes at early ages based on thermogravimetric analysis (TGA)

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    [EN] Ordinary thermogravimetric analysis (TG) and high-resolution TG tests were carried out on three different Portland cement pastes to study the phases present during the first day of hydration. Tests were run at 1, 6, 12 and 24 h of hydration, in order to determine the phases at these ages. High-resolution TG tests were used to separate decompositions presented in the 100¿200 C interval. The non-evaporable water determined by TG was used to determine hydration degree for the different ages. The effect of particle size distribution (PSD) on mineralogical evolution was established, as well as the addition of calcite as mineralogical filler. Finer PSD and calcite addition accelerate the hydration process, increasing the hydration degree on the first day of eaction between water and cement. According to high-resolution TG results, it was demonstrated that ettringite was the only decomposed phase in the 100¿200 C interval during the first 6 h of hydration for all studied cements. 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