Browsing by Issue Date, starting with "2021-05"
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- Babel e Sião : um manuscrito da Camoniana de D. Manuel IIPublication . Fraga, Maria do CéuEste livro reúne e estuda dois textos que estavam destinados à inacabada edição comentada das "Rimas" camonianas: o comentário inédito que Faria e Sousa fez a «Sôbolos rios que vão», poema conhecido também sob o título "Babel e Sião", e uma polémica explicação, igualmente inédita, sobre a composição e a história dessa forma típica da poesia ibérica que é a redondilha.
- Aqueous and Ethanolic Plant Extracts as Bio-Insecticides : Establishing a Bridge between Raw Scientific Data and Practical RealityPublication . Tavares, Wilson R.; Barreto, Maria do Carmo; Seca, Ana M. L.Global demand for food production is causing pressure to produce faster and bigger crop yields, leading to a rampant use of synthetical pesticides. To combat the nefarious consequences of its uses, a search for effective alternatives began in the last decades and is currently ongoing. Nature is seen as the main source of answers to crop protection problems, supported by several examples of plants/extracts used for this purpose in traditional agriculture. The literature reviewed allowed the identification of 95 plants whose extracts exhibit insecticide activity and can be used as bio-pesticides contributing to sustainable agriculture. The option for ethanol and/or water extracts is more environmentally friendly and resorts to easily accessible solvents, which can be reproduced by farmers themselves. This enables a bridge to be established between raw scientific data and a more practical reality. Azadirachta indica, Capsicum annuum, Nicotiana tabacum and Tagetes erecta are the most researched plants and have the potential to be viable options in the pest management approach. Azadirachta indica showed the most promising results and Brevicoryne brassicae was the most targeted pest species, being tested against the aqueous and/or ethanolic extracts of 23 different plants. Maceration using dried material (usually leaves) is the extraction method preferred by the majority of authors.
- Fine‐grain beta diversity of Palaearctic grassland vegetationPublication . Dembicz, Iwona; Dengler, Jürgen; Steinbauer, Manuel J.; Matthews, Thomas J.; Bartha, Sándor; Burrascano, Sabina; Chiarucci, Alessandro; Filibeck, Goffredo; Gillet, François; Janišová, Monika; Palpurina, Salza; Storch, David; Ulrich, Werner; Aćić, Svetlana; Boch, Steffen; Campos, Juan Antonio; Cancellieri, Laura; Carboni, Marta; Ciaschetti, Giampiero; Conradi, Timo; De Frenne, Pieter; Dolezal, Jiri; Dolnik, Christian; Essl, Franz; Fantinato, Edy; García‐Mijangos, Itziar; Giusso del Galdo, Gian Pietro; Grytnes, John‐Arvid; Guarino, Riccardo; Güler, Behlül; Kapfer, Jutta; Klichowska, Ewelina; Kozub, Łukasz; Kuzemko, Anna; Löbel, Swantje; Manthey, Michael; Marcenò, Corrado; Mimet, Anne; Naqinezhad, Alireza; Noroozi, Jalil; Nowak, Arkadiusz; Pauli, Harald; Peet, Robert K.; Pellissier, Vincent; Pielech, Remigiusz; Terzi, Massimo; Uğurlu, Emin; Valkó, Orsolya; Vasheniak, Iuliia; Vassilev, Kiril; Vynokurov, Denys; White, Hannah J.; Willner, Wolfgang; Winkler, Manuela; Wolfrum, Sebastian; Zhang, Jinghui; Biurrun, IdoiaQUESTIONS: Which environmental factors influence fine-grain beta diversity of vegetation and do they vary among taxonomic groups? LOCATION: Palaearctic biogeographic realm. METHODS: We extracted 4,654 nested-plot series with at least four different grain sizes between 0.0001 m² and 1,024 m² from the GrassPlot database, covering a wide range of different grassland and other open habitat types. We derived extensive environmental and structural information for these series. For each series and four taxonomic groups (vascular plants, bryophytes, lichens, all), we calculated the slope parameter (z-value) of the power law species–area relationship (SAR), as a beta diversity measure. We tested whether z-values differed among taxonomic groups and with respect to biogeographic gradients (latitude, elevation, macroclimate), ecological (site) characteristics (several stress–productivity, disturbance and heterogeneity measures, including land use) and alpha diversity (c-value of the power law SAR). RESULTS: Mean z-values were highest for lichens, intermediate for vascular plants and lowest for bryophytes. Bivariate regressions of z-values against environmental variables had rather low predictive power (mean R² = 0.07 for vascular plants, less for other taxa). For vascular plants, the strongest predictors of z-values were herb layer cover (negative), elevation (positive), rock and stone cover (positive) and the c-value (U-shaped). All tested metrics related to land use (fertilization, livestock grazing, mowing, burning, decrease in naturalness) led to a decrease in z-values. Other predictors had little or no impact on z-values. The patterns for bryophytes, lichens and all taxa combined were similar but weaker than those for vascular plants. CONCLUSIONS: We conclude that productivity has negative and heterogeneity positive effects on z-values, while the effect of disturbance varies depending on type and intensity. These patterns and the differences among taxonomic groups can be explained via the effects of these drivers on the mean occupancy of species, which is mathematically linked to beta diversity.
- Secondary Metabolites in Edible Species : Looking beyond Nutritional ValuePublication . Seca, Ana M. L.; Trendafilova, AntoanetaSecondary metabolites are organic molecules of low molecular weight, biosynthesized by any living being using a wide range of biosynthetic pathways, known as secondary metabolism. In evolutionary terms, secondary metabolism is seen as a set of specialized pathways that use a varied and specialized series of enzymes. Secondary metabolism aims to produce molecules with specific functions that promote the adaptability and survival of the species. However, secondary metabolites are not molecules essential to life, as are the lipids, carbohydrates and amino acids involved in basic life functions and produced by the primary metabolism. Terrestrial plants and algae, because they are sessile species, synthesize an admirable structural diversity of secondary metabolites. […]. (excerpt)
- Factors influencing the relative abundance of invasive predators and omnivores on islandsPublication . Lamelas-López, Lucas; Santos, Maria J.Invasive alien species (IAS) are the major cause of native species extinctions on islands worldwide. To mitigate or eliminate IAS impacts, eradication is often the best alternative. However, IAS removal may result in cascading effects, through increase in prey abundance, mesopredator release, or competitor release. Our objective is to determine which ecological processes may influence the relative abundance of invasive carnivores and rodents on an insular system. We find that feral cat and mustelids relative abundance was strongly related by prey abundance, and for the feral cat, abundance was also controlled by habitat; these results suggest that bottom-up control through environmental filtering could be the mechanism explaining predator abundance. For rodents, we find that the abundance of the black rat was mostly controlled by the abundance of Norway rat and house mice, and food availability; the Norway rat by the abundance of black rat, a house mice and of mustelid predators; and house mouse by the other rodents and food availability. These results suggest that several mechanisms could be concurrently controlling abundance of these species; competition and predation for Norway rat, and competition and bottom-up control by environmental filtering for the other two rodents. While different factors explain the abundance of invasive species within the same functional group, food resource availability is, in general, the main controller of abundance of invasive rodents and carnivores in the Azores. Therefore, IAS management actions in these islands should focus on limiting the access to food resources and shelter, mainly near to human populations.
- The representation potential of raptors for globally important nature conservation areasPublication . Santangeli, Andrea; Girardello, MarcoStemming from a pervasive lack of knowledge on biodiversity, important areas for conservation are typically identified using a subset of well known species, commonly termed surrogate or indicator groups. Birds have been commonly used as biodiversity surrogates due to the good level of knowledge on their taxonomy, ecology and distribution. Raptors in particular have been often proposed as an effective surrogate for other biodiversity based on their dietary diversity, being at the top of the food chain, their preference for highly productive areas, their generally threatened status and high public appeal. However, so far the surrogacy effectiveness of raptors has been largely studied locally or using a narrow selection of surrogate and surrogated taxa. Here we use a spatial conservation planning tool to quantify the surrogacy performance of raptors, overall and by different raptor groups (hawks and eagles, falcons, vultures, owls) to represent important biodiversity areas (such as IUCN protected areas and key biodiversity areas), wilderness areas and the worlds ecoregions. We compared the above surrogacy performance with that of all other non-raptor avian species. We show that raptors perform marginally worse than all other avian species in representing important biodiversity areas and ecoregions. However, raptors representation for wilderness areas was similar or slightly better compared to that of using all non-raptor birds. We also report a large variation in the representation performance by the four raptor groups. Falcons had a particularly high potential in representing protected areas and wilderness areas, equaling or largely surpassing the representation potential provided by all raptors and all other non-raptor birds. Overall, the results suggest that raptors, and particularly falcons, can perform relatively well in representing some important areas for conservation, such as protected areas and wilderness areas, but are relatively poor surrogates for key biodiversity areas and ecoregions. These rather contrasting results call for caution on the use of raptors as global surrogates of wider biodiversity.
- Património Cultural na MacaronésiaPublication . Gil, Ana Cristina Correia, dir.; Fialho, Adolfo Fernando da Fonte, ed.Neste número, a rubrica Ágora apresenta-nos o site "Património Cultural na Macaronésia", uma plataforma de gestão de conteúdos, para a transferência de conhecimento do trabalho de investigação realizado na área do património e a conversa escrita da voz as expetativas e projetos de Rute Gregório, Presidente da FCSH, para o mandato que agora se inicia.
- Costs and Benefits of Wax Production in the Larvae of the Ladybeetle Scymnus nubilusPublication . Pacheco, Paulo A. B.; Borges, Isabel; Branco, Beatriz; Lucas, Éric; Soares, António O.BACKGROUND: Larvae of the minute aphidophagous Scymnus nubilus Mulsant (Coleoptera: Coccinellidae) are common predators in apple orchards, covered by a wax layer that might act as a defense mechanism against natural enemies. However, the costs and benefits of protection conferred by wax remain to be assessed. We tested the following hypothesis: there is a trade-off in wax producing ladybeetles between the protection conferred by wax cover and the physiological or behavioral costs associated with its production. We predict that: (1) wax production is an efficient defensive mechanism (against intraguild predation), (2) wax production is associated with detrimental physiological (growth, reproduction) or behavioral effects (behavioral compensation: increased biomass consumption). RESULTS: Tests were carried out in the laboratory with wax and waxless larvae of S. nubilus, with and without lacewing larvae of Chrysoperla agilis (Neuroptera: Chrysopidae) being used as a potential intraguild predator of the coccinellid. Waxless individuals were more susceptible to intraguild predation by lacewing larvae. Adults originating from waxless larvae were lighter than the ones originating from wax larvae, suggesting a metabolic cost resulting from a constant need of wax production. Body-weight gain and conversion efficiency were lower in waxless larvae. Biomass consumption was similar, showing that waxless larvae did not compensate for the physiological cost by eating more aphid biomass. CONCLUSION: The results indicate the potential existence of a trade-off between growth and protection associated with wax production.
- Birds that are more commonly encountered in the wild attract higher public interest onlinePublication . Mittermeier, John C.; Roll, Uri; Matthews, Thomas J.; Correia, Ricardo; Grenyer, RichLarge body size, the defining characteristic of "charismatic megafauna," is often viewed as the most significant correlate of higher public interest in species. However, common, local species (many of which are not large) can also generate public interest. We explored the relative importance of body size versus local occurrence in patterns of online interest in birds using a large sample of digital human-wildlife interactions (367 million Wikipedia pageviews) that included more than 10,000 bird species and a range of cultural and geographic contexts (represented by 25 Wikipedia language editions). We compared interest in Wikipedia, as measured by pageviews, with a bird's body size and its regional observation frequency (using data from ). We found that local species (i.e., those that occur in the wild in the country responsible for the majority of a Wikipedia language edition's pageviews) attract more pageviews than global species. Both body size and observation frequency had a positive correlation with Wikipedia pageviews across languages, but eBird observation frequency explained more of the variance in pageviews on average. In a model that included both observation frequency and body size, observation frequency was a significantly better predictor of pageviews than body size in 24 of 25 languages. Our results demonstrate that the opportunity to encounter birds in the wild is a significant correlate of increased online interest in birds across multiple linguistic and geographic contexts. This relationship provides insight into why some species attract greater interest than others and emphasizes the overlooked potential of common species in conservation marketing.
- Como as nanopartículas nos defendem da COVID-19 : entregas da vacina de RNAm diretamente às célulasPublication . Barreto, Maria do Carmo; Vasconcelos, Helena Cristina[…]. O prefixo “nano” indica pequeníssimo tamanho, tão pequeno, que permite as NPs atravessarem facilmente as membranas celulares e chegar aos locais-chave, podendo ser administradas por injeções intramusculares. Há cerca de 60 anos, o físico Richard Feynman (Prémio Nobel da Física em 1965), falou pela primeira vez na possibilidade de “manipular e controlar objetos a escala atómica” e “dispor os átomos da forma que queremos”, procedimentos que atualmente fazem parte da atividade experimental na área dos nanomateriais. Além disso, também lançou a ideia de que nanorobots poderiam ser injetados no corpo humano para realizar procedimentos médicos, tal como se pudéssemos “engolir o médico” … (um conceito inovador! e arrojado para a época; esta e outras ideias foram reunidas no livro “Surely You’re Joking, Mr. Feynman!”: Adventures of a Curious Character). As NPs de SiO₂ não são robots, mas têm mostrado um excelente desempenho na área da medicina, especialmente na entrega direcionada de vacinas, devido à estabilidade química, biocompatibilidade e baixa toxicidade que exibem. […].