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  • Doutoramento Honoris Causa: Pepetela
    Publication . Guerreiro, J.; Silva, António Correia e; Santos, Artur Carlos Mauricío Pestana dos
    Tocou-me vivamente o gesto da Universidade do Algarve, ao se lembrar de me outorgar o título de Doutor Honoris Causa. Compreendo o gesto como vontade de homenagem que ultrapassa o próprio homenageado, mas também e principalmente visa uma literatura e uma nação, a angolana. Porque muito dificilmente se separará a obra e a vida de um escritor da história e cultura do seu povo. Agradeço profundamente a ideia desta celebração, que muito me honra e quero pois dedicá-la, com vossa permissão, ao povo angolano. Dedico-a também à minha mãe, que, como verão em seguida, teve um papel decisivo no meu percurso e à minha mulher, Filomena, infelizmente ausente nesta ocasião, responsável pelo menos por metade daquilo que tenho produzido. Agradeço também as generosas palavras de apresentação do Magnífico Reitor da Universidade de Cabo Verde, o Professor António Correia e Silva. No meu fraco entender, considero que um ficcionista deve contar preferentemente estórias e não falar ou escrever sobre aquilo que é o seu trabalho íntimo, talvez o mais íntimo dos trabalhos humanos. Chamemos discrição ou suma vaidade a este cuidado de não revelar intimidades. Há porém escritores, também especialistas em teoria literária e que, sem cair em esquizofrenias, conseguem analisar, ponderar e divulgar aquilo que vão descobrindo nos textos ditados pela sua própria imaginação (alguns denominam subconsciente). Admiro a sua capacidade e até ousadia de exposição, mas sou incapaz de os seguir. Da mesma maneira, não sou capaz de escrever mais de dez linhas sobre o trabalho de outro escritor sem começar a contar estórias que a meus olhos melhor o definem em contraposição às analíticas palavras habituais.
    2020-09Book Open Access Show more
  • The Late Pleistocene-Holocene sedimentary evolution of the Sines Contourite Drift (SW Portuguese Margin): A multiproxy approach
    Publication . Teixeira, Manuel; Terrinha, Pedro; Roque, Cristina; Voelker, Antje; Silva, Pedro; Salgueiro, Emilia; Abrantes, Fatima; Naughton, Filipa; Mena, Anxo; Ercilla, Gemma; Casas, David
    The Sines Contourite Drift (SCD), located in the Alentejo margin, southwest Iberian continental margin, has been through many depositional phases in result of dimatic variations and bottom current oscillations, which determined a variable depositional pattern and an irregular sedimentary evolution since the Late Pleistocene. The SCD, being in the main path of the Mediterranean Outflow Water (MOW), which greatly constrains the sedimentary building of this drift, constitutes the distal part of the Gulf of Cadiz Contourite Depositional System and its sedimentary evolution therefore reflects the history of MOW variations. In order to investigate this, we report on a multiproxy analysis of grain-size, carbon content and physical, geochemical, and environmental-magnetic properties on the AMS C-14 dated 350-an long gravity core CO14-GC-07, retrieved in the SCD, at 1425 meters water depth (mwd). The main objective is to reconstruct the evolution of the sedimentary package of the SCD from >43 cal kyr BP to Present and bring new insights about the impact of bottom currents' activity on the morphosedimentary evolution of the margin. Results show the existence of four distinct depositional phases in response to climate variations and bottom current oscillations during the Late Pleistocene-Holocene. Phase 1 (350-322 cm: >42.9 cal kyr BP) occurred in Marine Isotope Stage (MIS) 3 and presents silty-muddy sediments with presence of shell fragments and moderate bioturbation. Phase 2 (322-176 cm: >42.9-similar to 30.5 cal kyr BP), which lasted from middle MIS 3 to the onset of MIS 2, reveals sediment coarsening towards the top limit, suggesting climate cooling and strong bottom current winnowing. Phase 3 (176-144 cm: similar to 30.5-17.1 cal kyr BP) covers most of MIS 2 prior to the last deglaciation and shows the sharpest variations on all sediment properties and the coarsest sediment facies, with Fe-rich layers associated with the increase of lerrigenous input and sea-level regression that coincide with the enhancement of MOW. Phase 4 (144-0 cm: <17.1 cal kyr BP) is associated with the degladal sea-level rise and represents a calmer depositional environment with finer sediments and increasing contributions of biogenic material. The MOW is the most prominent bottom current and the most active seabed shaping agent in the study area, whose vertical shifting during glacial (similar to 800-2200 mwd) and interglacial (600-1500 mwd) periods is coincident with the most active morphosedimentary sector of the area, contributing to the development of landslide scars and sediment waves. (C) 2020 Elsevier B.V. All rights reserved.
    2020-09Journal article Restricted Show more
  • Ischemic stroke and subarachnoid hemorrhage following Epstein-Barr virus infection
    Publication . Rios, Jonathan; Félix, Catarina; Proença, Paula; Malaia, Luís; Nzwalo, Hipólito
    The epidemiological link between inflammation, infection, and acute ischemic stroke (AIS) is well known.1 Transient prothrombotic status and vasculitis are possible explanatory factors.1 Aneurysm formation in association with central nervous system infections is occasionally reported.2 Ischemic or hemorrhagic complication in relation to neurotropic virus infections, including Epstein-Barr Virus (EBV) are rarely reported in adults. Thus, we report here an extremely rare case of ischemic and hemorrhagic cerebrovascular complications in the context of EBV neuroinfection.
    2020-09Journal article Open Access Show more
  • Genetic affinities and biogeography of putative Levantine-endemic seaweed Treptacantha rayssiae (Ramon) M.Mulas, J.Neiva & A.Israel, comb. nov. (Phaeophyceae)
    Publication . Mulas, Martina; Neiva, J.; Sadogurska, Sofia S.; Ballesteros, Enric; Serrao, Ester; Rilov, Gil; Israel, Alvaro
    Cystoseira sensu lato (Ochrophyta) forests are important habitat formers in the Mediterranean Sea, but they have mostly been studied in the western basin where many species are under decline. In the eastern basin, where fewer species occur, Cystoseira rayssiae Ramon was described in the year 2000 as an endemic species based on morphological characteristics from herbaria samples collected on the Israeli coast. No further investigations have been conducted on this peculiar species since, but recently it has been recorded in contiguous Lebanon and outside the Mediterranean. Our work was aimed at confirming the taxonomic validity and endemic nature of this species, including its position among the recently split Cystoseira sensu stricto, Carpodesmia Greville and Treptacantha Kutzing genera, by sequencing the mitochondrial COI gene and by examining morphological characteristics in samples from three different sites in northern Israel. Notwithstanding considerable morphological plasticity, molecular analyses revealed a single unique COI sequence. Phylogenetic analyses show that Cystoseira rayssiae belongs to the resurrected genus Treptacantha and hence, the new combination Treptacantha rayssiae (Ramon) M.Mulas, J.Neiva & A.Israel, comb. nov., is proposed. Unique sequences and a restricted range support its Levantine-endemic status. Intriguing extra-Mediterranean reports from the Red Sea and the Persian Gulf are probably misidentifications rather than reflecting a disjunct distribution or recent invasion.
    2020-09Journal article Restricted Show more
  • Antioxidant, antimicrobial, and bioactive potential of two new haloarchaeal strains isolated from Odiel Salterns (Southwest Spain)
    Publication . Gómez-Villegas, Patricia; Vigara, Javier; Vila, Marta; Varela, João; Barreira, Luísa; Léon, Rosa
    The need to survive in extreme environments has furnished haloarchaea with a series of components specially adapted to work in such conditions. The possible application of these molecules in the pharmaceutical and industrial fields has received increasing attention; however, many potential bioactivities of haloarchaea are still poorly explored. In this paper, we describe the isolation and identification of two new haloarchaeal strains from the saltern ponds located in the marshlands of the Odiel River, in the southwest of Spain, as well as the in vitro assessment of their antioxidant, antimicrobial, and bioactive properties. The acetone extract obtained from the new isolated Haloarcula strain exhibited the highest antioxidant activity, while the acetone extracts from both isolated strains demonstrated a strong antimicrobial activity, especially against other halophilic microorganisms. Moreover, these extracts showed a remarkable ability to inhibit the enzyme cyclooxygenase-2 and to activate the melanogenic enzyme tyrosinase, indicating their potential against chronic inflammation and skin pigmentation disorders. Finally, the aqueous protein-rich extracts obtained from both haloarchaea exhibited an important inhibitory effect on the activity of the acetylcholinesterase enzyme, involved in the hydrolysis of cholinergic neurotransmitters and related to several neurological diseases.
    2020-09Journal article Open Access Show more
  • Investigação em Educação Social – prática e reflexão
    Publication . Barros, Rosanna; Fragoso, António
    Passados quatro anos desde a publicação (versão impressa) do volume I do livro: Investigação em Educação Social – prática e reflexão, mantemos constante o alento de contribuir para amplificar o bom trabalho de intervenção socio educacional que se vem fazendo na região do Algarve, isto por continuarmos a acreditar que bons testemunhos de prática e reflexão são fontes preciosas de inspiração para todos os educadores sociais. Assim sendo, compilamos as melhores produções que neste interregno de tempo ocorreram no âmbito académico na Universidade do Algarve, com a ambição de proporcionar ao leitor novos horizontes de reflexividade que impulsionem a praxis, como resultado desta nova partilha de saberes (e interrogações). O Volume II deste livro1 compila um conjunto de onze textos inéditos resultantes de reflexão e pesquisa avançada, e, desde logo, representa um alargamento do repertório de experiências e perspetivas de investigação em educação social. Concretizamos este segundo volume do livro partindo dos mesmos dois pressupostos estratégicos: i) o primeiro é que, em termos das Instituições do Ensino Superior Portuguesas, a Universidade do Algarve continua a dar um contributo, ininterrupto e relevante, para ampliar o património de conhecimento nesta área, que interessa disseminar; e ii) o segundo é que, ao reinvestir numa obra coletiva em que valorizamos os jovens investigadores, sublinhamos, publicamente, a importância que lhes concedemos, apostando e acreditando nas novas gerações, nas suas sinergias e ângulos de observação inovadores sobre a época atual e as problemáticas socias prementes e em rápida transformação. Acreditamos que os dois volumes deste livro, produzidos até à data, explicitam a diversidade dos aspetos praxiológicos que fazem parte do âmbito de intervenção da Educação Social, bem como a amplitude de possibilidades de abordagem teórico-conceptuais que enformam o saber especializado e relacional dos profissionais desta área, cuja base ético-deontologia é essencial para balizar processos de transformação social participados pelas comunidades, com sentido emancipador.
    2020-09Book Open Access Show more
  • Behavioural aspects of the spotty bobtail squid Euprymna parva (Cephalopoda: Sepiolidae)
    Publication . Drerup, Christian; Sykes, António; Cooke, Gavan M.
    Bobtail squids (Sepiolidae, Cephalopoda) have recently been growing in popularity in scientific studies due to their symbiotic relationship with light producing bacteria and their corresponding light emitting organs. However, the overall knowledge on the behaviour of sepiolids is based on observations on just a few of the roughly 70 extant species and must still be considered as sparsely. Understanding their behavioural ecology is not only beneficial to further grasp the complex behavioural patterns of cephalopods, it is also vital for establishing a good welfare practice when holding sepiolids in captivity. Hence, the present study characterised several behavioural aspects of the spotty bobtail squid Euprymna parva. Although the burying, hunting and mating behaviour as well as most escape responses of this less investigated sepiolid species greatly resembled those of other observed bobtail squids, differences to sepiolids from other genera or even from the same genus could be identified in the present study. Additionally, the first observation of an up to now undescribed inking behaviour of sepiolids is reported. E. parva was observed to eject a stretch of ink ('ink rope'), approximately 4-5 times the length of the animal, and hold on to it motionless, potentially as a masquerade to resemble a floating seagrass leave. The present study further provides detailed information on daily time and activity budgets as well as the tentacular strike speed during hunting, two up to now barely investigated behavioural aspects of the sepiolid ecology.
    2020-09Journal article Restricted Show more
  • Exploring Ulva australis Areschoug for possible biotechnological applications: In vitro antioxidant and enzymatic inhibitory properties, and fatty acids contents
    Publication . Trentin, Riccardo; Custódio, Luísa; Rodrigues, Maria Joao; Moschin, Emanuela; Sciuto, Katia; Da Silva, José Paulo; Moro, Isabella
    Ulva australis Areschoug (Ulvales, Chlorophyta) is traditionally used as a foodstuff in Korea and to treat several diseases, such as hyperlipidemia and urinary ailments. It is now considered an invasive species of the Venice Lagoon (Italy). This work explored U. australis as a potential source of bioactive molecules with biotechnological applications. For that purpose, organic and water extracts were prepared from dried biomass of U. australis and evaluated for radical scavenging activity (RSA), metal chelating activities and for in vitro inhibition of enzymes related with several disorders, namely Alzheimer's disease (acetylcholinesterase, butyrylcholinesterase), hyperpigmentation (tyrosinase), obesity (lipase), Type-2 diabetes mellitus (alpha-glucosidase, alpha-amylase) and skin sagging (elastase). Extracts were also evaluated for total contents of phenolics, flavonoids condensed tannins and carbohydrates. Finally, the fatty acids methyl esters profile of the biomass was established by gas chromatography-mass spectrometry. Extracts had low to moderate radical scavenging activity on DPPH, and a higher ability to chelate Fe2+ than Cu2+, and the maximum Fe2+ chelating capacity was observed in the tincture (IC50 = 4.82 mg/mL). Samples had a higher ability to inhibit alpha-amylase and microbial alpha-glucosidase than the other tested enzymes. The biomass of U. australis presented a highly saturated fatty acids profile, enriched in palmitic acid. These data suggest U. australis as a promising source of natural products with anti- diabetic properties and as a desirable species for biodiesel production.
    2020-09Journal article Restricted Show more
  • Nonlinear vacuum electrodynamics and spontaneous breaking of Lorentz symmetry
    Publication . Escobar, C. A.; Potting, Robertus
    We study spontaneous breaking of Lorentz symmetry in nonlinear vacuum electrodynamics. Using a first-order formulation of the latter proposed by Plebanski, we apply a Dirac constraint analysis and derive an effective Hamiltonian. We show that there exists a large class of potentials for which the effective Hamiltonian is bounded from below, while at the same time possessing local minima in which the field strength acquires a nonzero vacuum expectation value, thereby breaking Lorentz invariance spontaneously. These possible vacua can be classified in four classes, depending on the way Lorentz symmetry is broken. We show that the small field fluctuations around these vacua involve modes for which the dynamics can develop degeneracies, resulting in shock-wave-like and/or superluminal motion. Finally, we study the physical applicability of these models, and show how the Lorentz breaking vacua might in principle be detected by coupling the model to a suitable external current, or to gravity.
    2020-09Journal article Restricted Show more
  • ZFBONE: an ImageJ toolset for semi-automatic analysis of zebrafish bone structures
    Publication . Tarasco, Marco; Cordelieres, Fabrice P.; Cancela, M. Leonor; Laizé, Vincent
    The last decade has seen an increased interest in the discovery of compounds with bone anabolic activity to treat skeletal disorders such as osteoporosis and increase the well-being of patients. Due to the many technical advantages over classical rodent systems, zebrafish (Danio rerio) has been increasingly used in screening pipelines, in particular those aiming at identifying osteoactive compounds with pharmacological potential. Because compound osteoactivity is mostly determined in zebrafish through the morphometric analysis of bone structures, image analysis, rather than screening assay implementation, molecule availability and image acquisition, represents a bottleneck to the screening throughput. The absence of auto/semi-automatic tools for image analysis of fish bone structures is also a limitation to a broader usage of zebrafish screening pipelines. We present here ZFBONE (for ZebraFish BONE), an open-source, freely available, user-friendly, rapid and reliable toolset, aiming at accelerating image analysis by automating the morphometric assessment of zebrafish bone structures, but also at increasing data accuracy by reducing operator bias. Tools included in ZFBONE allow users to assess, from 2D images, morphometric parameters of several bone structures (e.g. operculum, caudal fin rays and scales) but also the extent and the intensity of bone-specific colorations. ZFBONE has been developed using the open-source ImageJ software, to make it available to the whole zebrafish research community, but also to have it easily modifiable according to user demands. ZFBONE can also be used toward the standardization of zebrafish screening protocols in academia and industry.
    2020-09Journal article Restricted Show more