Browsing by Issue Date, starting with "2020-04"
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- Uncharted Source of Medicinal Products : The Case of the Hedychium GenusPublication . Tavares, Wilson R.; Barreto, Maria do Carmo; Seca, Ana M. L.A current research topic of great interest is the study of the therapeutic properties of plants and of their bioactive secondary metabolites. Plants have been used to treat all types of health problems from allergies to cancer, in addition to their use in the perfumery industry and as food. Hedychium species are among those plants used in folk medicine in several countries and several works have been reported to verify if and how effectively these plants exert the effects reported in folk medicine, studying their essential oils, extracts and pure secondary metabolites. Hedychium coronarium and Hedychium spicatum are the most studied species. Interesting compounds have been identified like coronarin D, which possesses antibacterial, antifungal and antitumor activities, as well as isocoronarin D, linalool and villosin that exhibit better cytotoxicity towards tumor cell lines than the reference compounds used, with villosin not affecting the non-tumor cell line. Linalool and α-pinene are the most active compounds found in Hedychium essential oils, while β-pinene is identified as the most widespread compound, being reported in 12 different Hedychium species. Since only some Hedychium species have been investigated, this review hopes to shed some light on the uncharted territory that is the Hedychium genus.
- A database of functional traits for spiders from native forests of the Iberian Peninsula and MacaronesiaPublication . Macías Hernández, Nuria; Ramos, Cândida; Domènech, Marc; Febles, Sara; Santos, Irene; Arnedo, Miquel A.; Borges, Paulo A. V.; Emerson, Brent C.; Cardoso, PedroThere is an increasing demand for databases including species trait information for biodiversity and community ecology studies. The existence of trait databases is useful for comparative studies within taxa or geographical regions, but there is low availability of databases for certain organisms. Here we present an open access functional trait database for spiders from Macaronesia and the Iberian Peninsula, recording several morphological and ecological traits related to the species life histories, microhabitat and trophic preferences.
- Dolphin whistle repertoires around São Miguel (Azores) : Are you common or spotted?Publication . Gannier, Alexandre; Fuchs, Sandra; Gannier, Adrien; Fernandez, Marc; Azevedo, José M. N.Short-beaked common dolphins (Delphinus delphis) and Atlantic spotted dolphins (Stenella frontalis) are both common in the Azores archipelago during summer. Because both species are sympatric, at least in part of their range, they may use acoustic features to recognize conspecifics and maintain school cohesion throughout their different activities. Delphinid whistles were recorded with a 96-kHz sampling rate using towed hydrophone system during surveys held in summer of 2013 and 2014 around São Miguel Island (Azores, Portugal). A total of 256 whistles attributed to either short-beaked common dolphin (n = 133) or Atlantic spotted dolphin (n = 123) were selected and processed with a contour extraction software. Elementary statistical analysis showed that duration, frequency and slope variables were significantly different for both species, although in most cases their range overlapped. We performed a discriminant analysis to test species classification: the dataset was randomly split into one calibration subset (186 whistles) and one validation subset (70 whistles). The discriminant analysis retained four variables (global slope, duration, minimal and final frequencies) as useful for classification. The discriminant function resulted in correct classification rates of 78.5% (calibration subset) and 81.4% (validation subset). Common dolphin whistles were better classified than Atlantic spotted dolphin whistles (83.4% and 74.8%) respectively. This study shows that reliable species identification can be achieved for common and spotted dolphins using their whistle repertoire characteristics.
- Porque não há um dialeto açorianoPublication . Gil, Ana Cristina Correia, dir.; Fialho, Adolfo Fernando da Fonte, ed.
- Using graph theory to analyse and assess changes in Mediterranean woodland connectivityPublication . Machado, Rui; Godinho, Sérgio; Guiomar, Nuno; Gil, Artur José Freire; Pirnat, JanezCONTEXT The Portuguese montado is an agro-silvopastoral system, similar to the Spanish dehesa, known for its cultural, economic and ecological value. Despite its importance, contrasting processes such as land abandonment and land use intensification, together with several other factors, have been responsible for montado degradation in the last decades. Biodiversitywise, assuring high levels of connectivity is vital for many species that, in turn, contribute to the natural processes on which a healthy and sustainable montado relies. OBJECTIVES To study the montado connectivity in the recent decades and infer what the changes represent to the short and medium dispersal species regarding habitat availability. METHODS The study was conducted in an area delimited by biogeographic boundaries in Southern Portugal where montado is abundant. We used a graph theory based approach and montado maps of 1984, 1999 and 2014 derived from remote sensing. RESULTS The results show a loss of montado associated to increasing fragmentation over time. This led to a global connectivity decrement likely to have negative implications for montado species. The most affected species are those more dependent on habitat characteristics, such as forest specialist birds, and those with low mobility that have lost great amounts of habitat not only due to montado loss but also due to the increasing fragmentation that makes suitable patches unreachable. CONCLUSIONS Given the montado environmental relevance, measures should be taken in order to stop its loss and preserve the core areas that have guaranteed the connectivity over time.
- Applications of sesquiterpene lactones : a review of some potential success casesPublication . Moujir, Laila M.; Callies, Oliver; Sousa, Pedro M. C.; Sharopov, Farukh; Seca, Ana M. L.Sesquiterpene lactones, a vast range of terpenoids isolated from Asteraceae species, exhibit a broad spectrum of biological effects and several of them are already commercially available, such as artemisinin. Here the most recent and impactful results of in vivo, preclinical and clinical studies involving a selection of ten sesquiterpene lactones (alantolactone, arglabin, costunolide, cynaropicrin, helenalin, inuviscolide, lactucin, parthenolide, thapsigargin and tomentosin) are presented and discussed, along with some of their derivatives. In the authors’ opinion, these compounds have been neglected compared to others, although they could be of great use in developing important new pharmaceutical products. The selected sesquiterpenes show promising anticancer and anti-inflammatory effects, acting on various targets. Moreover, they exhibit antifungal, anxiolytic, analgesic, and antitrypanosomal activities. Several studies discussed here clearly show the potential that some of them have in combination therapy, as sensitizing agents to facilitate and enhance the action of drugs in clinical use. The derivatives show greater pharmacological value since they have better pharmacokinetics, stability, potency, and/or selectivity. All these natural terpenoids and their derivatives exhibit properties that invite further research by the scientific community.
- Distribution of arbuscular mycorrhizal fungi (AMF) in Terceira and São Miguel Islands (Azores)Publication . Melo Drumonde, Catarina; Walker, Christopher; Freitas, Helena; Machado, Artur Câmara; Borges, Paulo A. V.The data, presented here, come from samples collected during three research projects which aimed to assess the impact of land-use type on Arbuscular Mycorrhizal Fungi (AMF) diversity and community composition in pastures of Terceira Island (Azores, Macaronesia, Portugal) and also in the native forest of two Azorean Islands (Terceira and São Miguel; Azores, Macaronesia, Portugal). Both projects contributed to improving the knowledge of AMF community structure at both local and regional scales.
- Lobophora (Dictyotales) species richness, ecology and biogeography across the North-Eastern Atlantic Archipelagos and Description of Two New SpeciesPublication . Vieira, Christophe; Henriques, Filipe; D'hondt, Sofie; Neto, Ana I.; Almada, Carmen H.; Kaufmann, Manfred; Sansón, Marta; Sangil, Carlos; Clerck, Olivier DeThe brown alga Lobophora (Dictyotales, Phaeophyceae) is an important macroalga in the North-eastern Atlantic archipelagos (i.e., Macaronesia). Notably in the Canaries it can dominate benthic assemblages. While the genus has been the subject of several ecological studies in the Canaries, no study has yet been conducted to assess species-level diversity of Lobophora in Macaronesia. We reassessed the diversity of Lobophora in Macaronesia, reporting the presence of seven species (L. caboverdeana sp. nov., L. canariensis, L. dagamae sp. nov., L. delicata, L. dispersa, L. littlerorum, and L. schneideri). Lobophora spp. from Macaronesia are morphologically and ecologically distinguishable. In the Canaries, L. schneideri dominates the photophilic assemblages from the intertidal to 20-30 m depth. Lobophora dagamae sp. nov. grows in less illuminated shallow habitats, and replaces L. schneideri from 30 to ~80 m. Lobophora canariensis also has a wide vertical distribution, from the intertidal to deep waters, while L. delicata, L. dispersa and L. littlerorum grow in shallow waters. The dominance of species with an upright habit versus prostrate or crustose species may be mediated by the pressure of herbivores. Four species have an amphi-Atlantic distribution: L. littlerorum, L. canariensis, L. delicata, and L. schneideri. Lobophora schneideri and L. delicata are furthermore distributed in the Mediterranean Sea. By sampling a pivotal region in the Atlantic, this study significantly improves our knowledge of Lobophora biogeography in the Atlantic Ocean. Macaronesia constitutes a species-poor region for Lobophora where no diversification events occurred, and a region of overlap between the Greater Caribbean and the Indo-Pacific.
- Global change in microcosms : environmental and societal predictors of land cover change on the Atlantic Ocean IslandsPublication . Norder, Sietze; Lima, Ricardo F.; Nascimento, Lea; Lim, Jun Y.; Fernández-Palacios, José María; Romeiras, Maria M.; Elias, Rui B.; Cabezas, Francisco J.; Catarino, Luís; Ceríaco, Luis M.P.; Castilla-Beltrán, Alvaro; Gabriel, Rosalina; Sequeira, Miguel M.; Rijsdijk, Kenneth F.; Nogué, Sandra; Kissling, W. Daniel; van Loon, E. Emiel; Hall, Marcus; Matos, Margarida; Borges, Paulo A. V.Islands contribute enormously to global biodiversity, but their species and ecosystems are highly threatened and often confined to small patches of remaining native vegetation. Islands are thus ideal microcosms to study the local dimensions of global change. While human activities have drastically transformed most islands, the extent to which societal and environmental conditions shape differences in land cover remains unclear. This study analyses the role of contrasting environmental and societal conditions in affecting the extent of native vegetation cover on 30 islands in five Atlantic Ocean archipelagos (Azores, Madeira, Canary Islands, Cape Verde, Gulf of Guinea Islands). We adopt a mixed-method approach in which we combine a statistical analysis of environmental and societal variables with a qualitative reconstruction of historical socioeconomic trends. Statistical results indicate that terrain ruggedness predominantly shapes the extent of remaining native vegetation cover, suggesting that topography constrains human impacts on biodiversity. Overall, environmental variables better explain differences in native vegetation cover between islands than societal variables like human population density. However, throughout history, islands experienced large changes in demography and socioeconomic trends, and therefore modern patterns of native vegetation might also partly reflect these past conditions. While anthropocene narratives often present humans as a global geophysical force, the results show that local environmental context strongly mitigated the degree of human impact on biodiversity. These findings call for integrative approaches to understand the contributions of local human-environment interactions to ongoing global change.
- As Ideias de Homem e de Universidade : Uma Tentativa de Definição determinada Pelo Entendimento de "Cultura" como "cultura homini"Publication . Silva, EduardoComo o seu título indica, o livro consiste maioritariamente numa tentativa de definição das Ideias de “Homem” e de “Universidade” determinada pelo entendimento de “cultura” como cultura homini—ou paideía, ou Bildung. Abre ele com um curto “Ante-Escrito” acerca da noção de “ensaio”, o qual ocupa as páginas 1–24. É, este, seguido de uma “Explicitação do sentido de ‘Ideia’ e de ‘Ideia de Homem” que o ensaio, no seu todo, considera, a qual ocupa as páginas 27–76. O livro termina com o referido ensaio, que o determina e justifica, que consiste na tentativa de definição para que o título remete e que ocupa as páginas 81–325.