87 research outputs found

    The ratio of pattern speeds in double-barred galaxies

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    We have obtained two-dimensional velocity fields in the ionized gas of a set of 8 double-barred galaxies, at high spatial and spectral resolution, using their Hα\alpha emission fields measured with a scanning Fabry-Perot spectrometer. Using the technique by which phase reversals in the non-circular motion indicate a radius of corotation, taking advantage of the high angular and velocity resolution we have obtained the corotation radii and the pattern speeds of both the major bar and the small central bar in each of the galaxies; there are few such measurements in the literature. Our results show that the inner bar rotates more rapidly than the outer bar by a factor between 3.3 and 3.6.Comment: 5 pages, 1 figure, 1 tabl

    Understanding the long-term dynamics of forest transition: Fromdeforestation to afforestation in a Mediterranean landscape (Catalonia, 1868-2005)

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    As other Mediterranean areas, Catalonia has experienced a forest transition following rural abandonmentduring the last sixty years. The GIS reconstruction of three land-use maps of 1868, 1956 and 2005 showshow forests have encroached former cropland and pasture land from the 1950s onwards, after a previouswave of deforestation. Forest inventories reveal the overpressure exerted on woodlands up to the 1950s,and their poor ecological status in terms of age structure, diversity and maturity. They are prone to wild-fires, which in turn force a harvest of salvaged wood by a sudden forestry activity that entails a viciouscircle: the lack of a proper forest management increases wildfires, and leads to this sort of 'spasmodicforestry'. To overcome this situation, a sustainable forestry, combined with farming and extensive live-stock breeding are needed as a means to perform an active ecological restoration. Historical knowledgecan help in this task, by discovering the previous dynamics of current woodlands and providing a guid-ance to differentiate the scarce oldest forests from the ones that are younger as a result of the overuseexerted up to mid-20th century, and from many others that have regrown since the 1950s in abandonedsteep lands

    Human breathable air in a Mediterranean forest: characterization of monoterpene concentrations under the canopy

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    Monoterpenes have been identified as potential determinants of the human health effects induced by forest exposure. The present study characterizes the total monoterpene concentrations at nose height in a Mediterranean Holm oak forest located in North-East Iberian Peninsula during the annual emission peak (summer and autumn: June to November) using a Proton Transfer Reaction–Mass Spectrometry (PTR-MS). Results show a strong variability of the total monoterpene concentrations in season and daytime. The concentration peak appears during July and August. These two months displayed two average maxima in their diel cycles: One during early morning (from 6:00 to 8:00, 0.30 ppbv for July and 0.41 ppbv for August) and another one at early afternoon (from 13:00 to 15:00, 0.27 ppbv during July and 0.32 ppbv during August). Monoterpene concentrations were strongly related with the temperature (exponentially) and solar radiation (rectangular hyperbolic relationship). The concentrations registered here are similar or higher than in previous ex situ studies showcasing the effects of forests on human health. These findings provide relevant data for the scientific and healthcare community by improving the understanding of monoterpene dynamics at nose height and suggesting further research on the effects of forests on human health, particularly in the Mediterranean region.The research leading to these results has received funding from “la Caixa” Foundation. Furthermore, this study was supported by the Spanish Government Grant CGL2013-48074-P, the Catalan Government grant SGR 2017-1005, the European Research Council Synergy grant ERC-2013-SyG 610028 IMBALANCE-P

    Intracellular pathways involved in cell survival are deregulated in mouse and human spinal muscular atrophy motoneurons

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    Spinal Muscular Atrophy (SMA) is a severe neuromuscular disorder caused by loss of the Survival Motor Neuron 1 gene (SMN1). Due to this depletion of the survival motor neuron (SMN) protein, the disease is characterized by the degeneration of spinal cord motoneurons (MNs), progressive muscular atrophy, and weakness. Nevertheless, the ultimate cellular and molecular mechanisms leading to cell loss in SMN-reduced MNs are only partially known. We have investigated the activation of apoptotic and neuronal survival pathways in several models of SMA cells. Even though the antiapoptotic proteins FAIM-L and XIAP were increased in SMA MNs, the apoptosis executioner cleaved-caspase-3 was also elevated in these cells, suggesting the activation of the apoptosis process. Analysis of the survival pathway PI3K/Akt showed that Akt phosphorylation was reduced in SMA MNs and pharmacological inhibition of PI3K diminished SMN and Gemin2 at transcriptional level in control MNs. In contrast, ERK phosphorylation was increased in cultured mouse and human SMA MNs. Our observations suggest that apoptosis is activated in SMA MNs and that Akt phosphorylation reduction may control cell degeneration, thereby regulating the transcription of Smn and other genes related to SMN function.This work was supported by grants from Instituto de Salud Carlos III, Fondo de Investigaciones Sanitarias, Unión Europea, Fondo Europeo de Desarrollo Regional (FEDER) “Una manera de hacer Europa” (PI17/00231 and PI20/00098) to RMS and AG; CERCA Program/Generalitat de Catalunya; and Spanish Agency of Research (Agencia Estatal de Investigacion-PID2019- 107286RB-I00) and CIBERNED to JXC. AS holds a fellowship from Universitat de Lleida and SdF holds a fellowship from “Ajuts de Promoció de la Recerca en Salut” (IRBLleida-Diputació de Lleida). We thank Elaine Lilly, PhD, for English language revision of the paper

    Evaluation and assessment of professional skills in the Final Year Project

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    In this paper, we present a methodology for Final Year Project (FYP) monitoring and assessment that considers the inclusion of the professional skills required in the particular engineering degree. This proper monitoring and clear evaluation framework provides the student with valuable support for the project implementation as well as for improving the quality of the projects, thereby reducing the academic drop-out rate. The proposed methodology has been implemented at the Barcelona School of Informatics at the Universitat Politècnica de Catalunya - BarcelonaTech. The FYP is structured around three milestones: project definition, project monitoring and project completion. Skills are assigned to each milestone according to the tasks required in that phase, and a list of indicators is defined for each phase. The evaluation criteria for each indicator at each phase are specified in a rubric, and are made public both to students and teachers. Thus, the FYP includes an exhaustive evaluation method distributed throughout the whole project implementation, thereby facilitating project organization for the student as well as providing a clear and homogeneous assessment framework. The methodology for the FYP organization, assessment and evaluation was launched and piloted over two semesters. We believe the experience to be general in the sense that it has been conducted as part of an ICT engineering degree, but may easily be extended to any other engineering degree.Postprint (author’s final draft
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