7,797 research outputs found

    Modelling the distribution of a commercial NE-Atlantic sea cucumber, Holothuria mammata : demographic and abundance spatio-temporal patterns

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    Funding: This study was financed by the Operational Programme Mar2020, MAR-02.01.01-FEAMP-0052, “Newcumber – Avanços para o cultivo sustentável de pepinos do mar”. It received further financial support from Fundação para a Ciência e Tecnologia (projects UIDB/04292/2020, UIDB/00006/2020, CoastNet – PINFRA/22128/2016, AB with the Scientific Stimulus Programme – CEECIND/00095/2017 and FA with the individual research grant 2020.09563.BD). This publication was financed by Portuguese national funds through FCT – Fundação IP under project reference UIDB/04292/2020, and by the European Union’s Horizon 2020 Research and Innovation Program under grant agreement N810139: Project Portugal Twinning for Innovation and Excellence in Marine Science and Earth Observation – PORTWIMS.There is an increasing demand for sea cucumbers, for human consumption, mainly from Asian markets and, as a consequence, NE-Atlantic species are now new targets for exploitation and exportation. Holothuria mammata is one of the most valuable species in Europe. However, the lack of historical economic interest in this species in most European countries has also led to a lack of studies concerning biological and ecological aspects on wild populations and this is a major issue for stock management. This study aims to determine the temporal and spatial patterns of distribution of H. mammata, considering its abundance and demographic structure in a NE-Atlantic area, SW Portugal, as a function of environmental conditions. For that, a population from a marine protected area was followed for 1 year at 1.5-month intervals. Throughout the coastal area, six sites were selected and at each sampling campaign three random transects per site and substrate (rock and sand) in which all H. mammata individuals were counted and measured. For each site and survey several environmental parameters of interest, from the water column, the sediment and substrate cover, were also measured. Generalized Linear Models were used to model the spatial and temporal distribution of the species according to environmental conditions, to determine the species’ habitat preferences. The distribution models indicate that abiotic and biotic parameters of the water column are not the main drivers shaping the distribution of H. mammata. The species has a patchy distribution, and its habitat preferences depend on environmental stability, the presence of shelter and habitat complexity, which is more important for smaller, more vulnerable, individuals, while bigger size classes tend to venture more into less stable environments in an opportunistic fashion. The knowledge of these population traits is determinant to develop stock management measures, which are now urgent to prevent the depletion of commercial sea cucumber populations in the NE-Atlantic. Sustainable fisheries policies should be developed and start by considering to delimit fishing areas and periods, considering the species spatial and temporal distribution patterns.Publisher PDFPeer reviewe

    Characterization of Soybean Cultivars for Biodiesel Production

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    Due to environmental issues involving the polluting gasesemission, Brazil has adopted the policy of using oil and biodiesel. For biodiesel production, the main raw material used in Brazil is soybean oil. The development of the numerous genotypes of this culture has always considered quantitative aspects. The objective was to qualitatively characterize 12 soybean cultivars for biodiesel production. The experimental design was randomized blocks with three replicates. The cultivars were sown in December 2016, in no-tillage system, in Ponta Grossa, Paraná, Brazil (-25.093056, -50.063327 UTM). The analyzed variables were: oil and protein contents, acidity index and specific mass. It was concluded that there were no significant differences among the cultivars for oil and protein contents. For the variables acidity index and specific mass, there were significant differences among the cultivars, being below the limits established by the Brazilian legislation for vegetable oil, but with potential for biodiesel production

    Descrição da biodiversidade terrestre e marinha dos Açores

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    1. Os Açores são um arquipélago isolado de nove ilhas oceânicas, pertence à região biogeográfica da Macaronésia e está entre as regiões mais ricas em fungos, plantas e animais da Europa. Este capítulo destaca o que sabemos sobre os fungos, a fauna e a flora dos habitats terrestres, dulçaquícolas e marinhos dos Açores. 2. Neste capítulo, são apresentadas as estimativas do número total de espécies e subespécies conhecidas actualmente nos Açores. Todos os grupos taxonómicos terrestres mais importantes foram analisados: fungos, líquenes, diatomáceas dulçaquícolas, briófitos (musgos, hepáticas e antocerotas), plantas vasculares (licófitas, fetos, gimnospérmicas e angiospérmicas), platelmintes (vermes), nemátodos, anelídeos (minhocas), moluscos terrestres (lesmas e caracóis), artrópodes (insectos, aracnídeos, milípedes, etc.) e vertebrados (peixes de água doce, anfíbios, répteis, aves e mamíferos). A presente obra inclui também espécies do ambiente marinho, como as algas (macroalgas), a maioria dos filos de invertebrados do litoral e os vertebrados marinhos (répteis, peixes e mamíferos). As listas de espécies e subespécies (Capítulos 2-15) são baseadas nos taxa identificados numa grande variedade de publicações, tendo essa informação sido compilada por um vasto grupo de especialistas. 3. Actualmente, o número total de taxa (espécies e subespécies) terrestres nos Açores está estimado em cerca de 6164 (cerca de 6112 espécies). A inclusão de uma listagem exaustiva das espécies de aves não-nidificantes e de uma listagem preliminar de espécies de aves potencialmente nidificantes acrescenta 325 espécies e subespécies ao total das espécies açorianas. 4. O número total de espécies e subespécies endémicas terrestres dos Açores é de cerca de 452 (411 espécies). Os animais são os mais diversos em endemismos, com 331 taxa (Arthropoda = 266; Mollusca = 49; Vertebrata = 14; Nematoda = 2), compreendendo cerca de 73% dos endemismos terrestres dos Açores. A percentagem de endemismo nos Mollusca (44%) é notável. As plantas vasculares contam com 73 endemismos, os Fungi (incluindo os líquenes) têm 34 e, tanto as diatomáceas dulçaquícolas como os briófitos, incluem sete espécies endémicas. 5. Quando comparada com os arquipélagos vizinhos da Macaronésia (Madeira e Canárias), a fauna e flora terrestres dos Açores é caracterizada por uma menor taxa de endemismo, de apenas 7%, contrastando com os cerca de 20% para a Madeira e de 30% para as Canárias. 6. No que diz respeito aos organismos marinhos, são listados 1883 taxa pertencentes a 16 filos. O número total de espécies e subespécies marinhas endémicas dos Açores é de cerca de 39, a maior parte delas moluscos (29 espécies). 7. O número total de taxa terrestres e marinhos (espécies e subespécies) nos Açores, está estimado em cerca de 8047. Os organismos marinhos agora listados, perfazem cerca de 23% da biodiversidade dos Açores. 8. O número total de taxa terrestres e marinhos (espécies e subespécies) endémicos dos Açores está estimado em cerca de 491.ABSTRACT: 1. The Azores is a remote oceanic archipelago of nine islands which belongs to the Macaronesia biogeographical region and is among the richest regions concerning fungi, plant and animal diversity in Europe. This chapter highlights what we know about the Azorean terrestrial, freshwater and marine Fungi, Flora and Fauna. 2. In this chapter we summarize the current estimates of the total number of species and subspecies presently known to occur in the Azores. The most important terrestrial taxonomic groups were studied: Fungi, Lichens, Bacillariophyta (freshwater diatoms), Bryophyta sensu lato (mosses, liverworts and hornworts), vascular plants – Tracheobionta, including Lycopodiophyta (quillworts), Pteridophyta (ferns), Pinophyta (gymnosperms) and Magnoliophyta (angiosperms), Platyhelminthes (flatworms), Nematoda (roundworms), Annelida (earthworms), Terrestrial Mollusca (slugs and snails), Arthropoda (millipedes, centipedes, mites, spiders, insects, etc.) and Vertebrata (freshwater fishes, amphibians, reptiles, birds and mammals). In addition, we expand this list to the marine realm, including Algae (macroalgae), coastal invertebrates (most Phyla) and marine vertebrates (fishes, reptiles and mammals). The list of species and subspecies (Chapters 2 to 15) is based on the taxa recognized in primary published literature sources, compiled by a vast group of experts. 3. Currently the total number of terrestrial taxa (species and subspecies) in the Azores is estimated of about 6164 (about 6112 species). The inclusion of an exhaustive listing of non breeding species and a preliminary list of potentially breeding species adds 325 species and subspecies of birds to the Azorean list of species. 4. The total number of terrestrial endemic species and/or subspecies from the Azores is about 452 (411 species). Animals are the most represented in this respect, with 331 taxa (Arthropoda = 266; Mollusca = 49; Vertebrata = 14; Nematoda = 2), that is, about 73% of the Azorean terrestrial endemics. The percentage of endemism within Mollusca (44%) is remarkable. Vascular plants have 73 endemic taxa, while Fungi (including Lichens) have 34, freshwater diatoms and bryophytes have seven endemic species each. 5. Compared to the other nearest Macaronesian archipelagos (Madeira and Canaries), the Azorean terrestrial fauna and flora is characterized by a lower percentage of endemism (only 7%, which contrasts with nearly 20% for Madeira and 30% for the Canary islands). 6. Concerning the marine organisms, we listed about 1883 taxa belonging to 16 Phyla. The total number of marine endemic species and/or subspecies from the Azores is about 39, most of them being molluscs (29 species). 7. Currently, the total number of terrestrial and marine taxa (species and subspecies) in the Azores is estimated in about 8047. The marine organisms currently listed make up about 23% of the Azorean biodiversity. 8. Currently, the total number of terrestrial and marine endemic taxa (species and subspecies) in the Azores is estimated of about 491

    Drying kinetics of thyme

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    [EN] This work aimed to study the drying kinetics of thyme and subsequent adjustment of different mathematical models to the experimental data and to determine the effective diffusivity and the activation energy. In order to conduct the experiment the temperatures of 30, 40, 50, 60, 70 ºC were used. The experimental design employed was in randomized blocks with three repetitions. For the adjustment of the mathematical models to the experimental data non-linear regression was performed using SimplexQuasi-Newton method. The results showed that the Page model was the one that promoted the best fit of the experimental data to describe the drying kinetics of the thyme leaves. The values of effective diffusivity coefficients ranged between 3.69 x 10-12 and 1.19 x 10-10 m2 s-1 and the value of activation was 77.16 kJ mol-1 .[ES] Los objetivos del trabajo fueran estudiar la cinética del secado de tomillo con posterior ajuste de diferentes modelos matemáticos a los datos experimentales determinar los valores de la difusividad efectiva y energía de activación. Para el desarrollo del experimento de secado fueran utilizadas las temperaturas 30, 40, 50, 60 y 70 oC. El diseño experimental fue de bloques completamente aleatorizados, con tres repeticiones. Para el ajuste de los modelos matemáticos a los datos experimentales fue realizado el análisis de regresión no lineal, por el método Simplex-Quasi-Newton. Los resultados mostraron que el modelo de Page obtuve un mejor ajuste a los datos experimentales, los valores de los coeficientes de difusividad efectiva variaron entre 3,69 x 10-12 e 1,19 x 10-10 m2 s-1 y el valor de la energía de activación fue de 77,16 kJ mol-1 .Da Rocha, RP.; Melo, EDC.; Bon Corbín, J.; Berbert, PA.; Donzeles, SML.; Tabar, JA. (2012). Cinética de secado de tomillo. Revista Brasileira de Engenharia Agrícola e Ambiental - Agriambi. 16(6):675-683. http://hdl.handle.net/10251/78997S67568316

    Cholinergic Signaling Exerts Protective Effects in Models of Sympathetic Hyperactivity-Induced Cardiac Dysfunction

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    Cholinergic control of the heart is exerted by two distinct branches; the autonomic component represented by the parasympathetic nervous system, and the recently described non-neuronal cardiomyocyte cholinergic machinery. Previous evidence has shown that reduced cholinergic function leads to deleterious effects on the myocardium. Yet, whether conditions of increased cholinergic signaling can offset the pathological remodeling induced by sympathetic hyperactivity, and its consequences for these two cholinergic axes are unknown. Here, we investigated two models of sympathetic hyperactivity: i) the chronic beta-adrenergic receptor stimulation evoked by isoproterenol (ISO), and ii) the alpha(2A)/alpha(2C)-drenergic receptor knockout (KO) mice that lack pre-synaptic adrenergic receptors. In both models, cholinergic signaling was increased by administration of the cholinesterase inhibitor, pyridostigmine. First, we observed that isoproterenol produces an autonomic imbalance characterized by increased sympathetic and reduced parasympathetic tone. Under this condition transcripts for cholinergic proteins were upregulated in ventricular myocytes, indicating that non-neuronal cholinergic machinery is activated during adrenergic overdrive. Pyridostigmine treatment prevented the effects of ISO on autonomic function and on the ventricular cholinergic machinery, and inhibited cardiac remodeling. alpha(2A)/alpha(2C)-KO mice presented reduced ventricular contraction when compared to wild-type mice, and this dysfunction was also reversed by cholinesterase inhibition. Thus, the cardiac parasympathetic system and non-neuronal cardiomyocyte cholinergic machinery are modulated in opposite directions under conditions of increased sympathetic drive or ACh availability. Moreover, our data support the idea that pyridostigmine by restoring ACh availability is beneficial in heart disease

    Polar lipids of commercial Ulva spp. of different origins: profiling and relevance for seaweed valorization

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    Macroalgae of the genus Ulva have long been used as human food. Local environmental conditions, among other factors, can have an impact on their nutrient and phytochemical composition, as well as on the value of the seaweed for food and non-food applications. This study is the first to initiate a comparison between commercial Ulva spp. from different European origins, France (FR, wild-harvested Ulva spp.), and Portugal (PT, farm-raised Ulva rigida), in terms of proximate composition, esterified fatty acids (FA), and polar lipids. The ash content was higher in PT samples, while FR samples had higher levels of proteins, lipids, and carbohydrates and other compounds. The profile of esterified FA, as well as FA-containing polar lipids at the class and species levels were also significantly different. The FR samples showed about three-fold higher amount of n-3 polyunsaturated FA, while PT samples showed two-fold higher content of monounsaturated FA. Quantification of glycolipids and phospholipids revealed, respectively, two-fold and three-fold higher levels in PT samples. Despite the differences found, the polar lipids identified in both batches included some lipid species with recognized bioactivity, valuing Ulva biomass with functional properties, increasing their added value, and promoting new applications, namely in nutraceutical and food markets.UIDB/50011/2020+UIDP/50011/2020, UID/QUI/00062/2019, UIDB/50006/2020, UIDB/50017/2020+UIDP/50017/2020, LISBOA-01-0145-FEDER-402-022125, POCI-01-0145-FEDER-030962, BPD/UI51/5041/2017, BPD/UI51/5042/2018; EC/H2020/727892/EUinfo:eu-repo/semantics/publishedVersio

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

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    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
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