1,198 research outputs found

    Chemical abundances and radial velocities in the extremely metal-poor galaxy DDO 68

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    We present chemical abundances and radial velocities of six HII regions in the extremely metal-poor star-forming dwarf galaxy DDO 68. They are derived from deep spectra in the wavelength range 3500 - 10,000 {\AA}, acquired with the Multi Object Double Spectrograph (MODS) at the Large Binocular Telescope (LBT). In the three regions where the [O III]λ\lambda4363 {\AA} line was detected, we inferred the abundance of He, N, O, Ne, Ar, and S through the "direct" method. We also derived the oxygen abundances of all the six regions adopting indirect method calibrations. We confirm that DDO 68 is an extremely metal-poor galaxy, and a strong outlier in the luminosity - metallicity relation defined by star-forming galaxies. With the direct-method we find indeed an oxygen abundance of 12+log(O/H)=7.14±\pm0.07 in the northernmost region of the galaxy and, although with large uncertainties, an even lower 12+log(O/H)=6.96±\pm0.09 in the "tail". This is, at face value, the most metal-poor direct abundance detection of any galaxy known. We derive a radial oxygen gradient of -0.06±\pm0.03 dex/kpc (or -0.30 dex R25−1R_{25}^{-1}) with the direct method, and a steeper gradient of -0.12±\pm0.03 dex/kpc (or -0.59 dex R25−1R_{25}^{-1}) from the indirect method. For the α\alpha-element to oxygen ratios we obtain values in agreement with those found in other metal-poor star-forming dwarfs. For nitrogen, instead, we infer much higher values, leading to log(N/O)∼−1.4\sim-1.4, at variance with the suggested existence of a tight plateau at −1.6-1.6 in extremely metal poor dwarfs. The derived helium mass fraction ranges from Y=0.240±\pm0.005 to Y=0.25±\pm0.02, compatible with standard big bang nucleosynthesis. Finally, we measured HII region radial velocities in the range 479−-522 km/s from the tail to the head of the "comet", consistent with the rotation derived in the HI.Comment: Accepted for publication in MNRA

    Towards a Timely Prediction of Earthquake Intensity with Social Media

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    A growing number of people is turning to Social Media in the aftermath of emergencies to search and publish critical and up to date information. Retrieval and exploitation of such information may prove crucial to decision makers in order to minimize the impact of disasters on the population and the infrastructures. Yet, to date, the task of the automatic assessment of the consequences of disasters has received little to no attention. Our work aims to bridge this gap, merging the theory behind statistical learning and predictive models with the data behind social media. Here we investigate the exploitation of Twitter data for the improvement of earthquake emergency management. We adopt a set of predictive linear models and evaluate their ability to map the intensity of worldwide earthquakes. The models build on a dataset of almost 5 million tweets and more than 7,000 globally distributed earthquakes. We run and discuss diagnostic tests and simulations on generated models to assess their significance and avoid overfitting. Finally we deal with the interpretation of the relations uncovered by the linear models and we conclude by illustrating how findings reported in this work can be leveraged by existing emergency management systems. Overall results show the effectiveness of the proposed techniques and allow to obtain an estimation of the earthquake intensity far earlier than conventional methods do. The employment of the proposed solutions can help understand scenarios where damage actually occurred in order to define where to concentrate the rescue teams and organize a prompt emergency response

    WorkMail: collaborative document workflow by email

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    Processing documents is a critical and crucial aspect in an enterprise environment. The management of documents involves several people and many times becomes a long and wasting-time process. Many systems of document workflow have been proposed but usually they are too rigid and complex. Therefore we have developed a document workflow engine based on the email paradigm. When a user wants to make an order, a request of authorization and, in general, any kind of procedure that involve a document, starts her/his request by filling in a form and sending it by attaching it to an email. To this purpose the user has to use our web application that appears as a normal webmail client. Our solution overcomes the actual limitation in the use of document workflow software, especially for what concern the user experience; with our system there is no need, for users, to learn the functioning of a new framework. In addition, users with different roles have different customized view of the document. According with the roles of the users, we trained the system to suggest to the user, at each step, a possible receiver of the email. Currently this feature is based on the fact that the system knows in advance the flow associated with different type of documents. As improvement, we will perform a statistical analysis of interactions between senders and receivers. This analysis will be used to improve the suggestion mechanism: the system will learn the most frequent interactions for each user, depending on the history of previous flow and the document involved. Exploiting these information, the suggestion mechanism will advise to the user the possible receiver of the document

    Living and Dead Aboveground Biomass in Mediterranean Forests: Evidence of Old-Growth Traits in a Quercus pubescens Willd. s.l. Stand

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    For a long time, human impact has deeply simplified most of the forest ecosystems of the Mediterranean Basin. Here, forests have seldom had the chance to naturally develop a complex and multilayered structure, to host large and old trees and rich biological communities, approaching old-growth conditions. Also for this reason, limited information is currently available about Mediterranean old-growth forests, particularly with regard to deadwood. The main aim of this work is to help fill this critical knowledge gap. In Sicily (Italy), we identified a Quercus pubescens forest that seemed to show some typical old-growth features. Total living volume (360 m3 ha 121) and basal area (34 m2 ha 121) were, respectively, about 6 and 3 times higher than the averages recorded in the regional forest inventory for this forest type. Deadwood was particularly abundant, exceeding the threshold of 30 m3 ha 121, mainly represented by lying dead elements. Dead to live wood ratio reached 9%, a value close to the threshold of 10% considered for Mediterranean old-growth forests. As the investigated forest showed some typical old-growth traits, it deserves to be fully protected and could be a permanent monitoring area for studying deadwood and stand dynamics in mature Mediterranean stands

    Treatment and timing in invasive mould disease

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    Invasive mould disease is a growing threat for immunocompromised patients. The optimum time to use mould-active antifungal agents is much debated. Current approaches to antifungal prophylaxis, early treatment (empirical and pre-emptive therapy) and treatment of documented mould infections in onco-haematology patients are discusse

    Topological Defects in the Abrikosov Lattice of Vortices in Type-II Superconductors

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    The free energy costs for various defects within an Abrikosov lattice of vortices are calculated using the lowest Landau level approximation (LLL). Defect solutions with boundary conditions for lines to meet at a point (crossing defect) and for lines to twist around each other (braid defect) are sought for 2, 3, 6, and 12 lines. Many results have been unexpected, including the nonexistence of a stable two- or three-line braid. This, and the high energy cost found for a six-line braid lead us to propose that the equilibrium vortex state is not entangled below the irreversibility line of the high-TcT_c superconductors or in a large part of the vortex-liquid phase above this line. Also, the solution for an infinite straight screw dislocation is found, and used to give a limiting form for the free energy cost of very large braids. This depends on the area enclosed by the braid as well as its perimeter length.Comment: 30 pages, 17 Encapsulated PostScript figures, uses Revtex (with epsf

    CNR@wOrK - a Social Network for CNR community

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    Social network sites (SNSs) are increasingly attracting the attention of academic and industry re-searchers intrigued by their affordance and reach. Most website, like Facebook, Twitter, LinkedIn and so on, connect people that don\u27t know each other based on shared interests, political views, photos, videos and in general important part of life. Some sites cater to diverse audiences, while others attract people based on common language or shared racial, sexual, religious, or nationali-ty-based identities. Social networking websites could be harnessed for immense benefit to the scientific sector. A scientific social network allows scientists to share ideas, details of their cur-rent research and freely distribute their results. It would reduce wasteful scientific redundancy, for instance, by preventing scientists from doing experiments others have done before them, and it would also enable cooperation between groups across the world. In this Technical Report we present our SNS platform called CNR@wOrK and discuss about its developments and future improvements

    Adaptive forest governance to face land use change impacts in Italy: a review

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    Il cambiamento dell’uso del suolo è uno dei driver principali della riduzione della resilienza ecosistemica, così come della perdita di biodiversità e approvvigionamento di servizi. Rappresenta una sfida peculiare, specialmente negli ambienti mediterranei, dove i fenomeni di abbandono e ricolonizzazione naturale stanno minacciando in modo sempre più crescente la capacità delle foreste di fornire benefici alle comunità locali. In queste condizioni, il sistema di governance forestale è chiamato a bilanciare gli impatti del cambiamento dell’uso del suolo con l’assicurazione della salute e della stabilità degli ecosistemi forestali, al fine di garantire la sostenibilità a lungo termine degli ambienti, soprattutto di quelli marginali. Questo lavoro si propone di analizzare in modo più approfondito gli impatti del cambiamento dell’uso del suolo sugli ecosistemi forestali negli ambienti montani italiani. In primo luogo, esegue un’analisi bibliografica dei concetti legati al cambiamento dell’uso del suolo e all’approvvigionamento dei servizi ecosistemici, dalla scala globale a quella locale. In seguito, indaga le relazioni fra le potenzialità adattive di gestione e pianificazione forestali e il cambiamento dell’uso del suolo. Infine, vengono proposte alcune strategie future di possibili strumenti di governance adattiva per affrontare i cambiamenti dell’uso del suolo. Questa infatti può migliorare la resilienza degli ecosistemi forestali riducendo il gap nel campo della ricerca tra il contesto nazionale e quello globale, utilizzando strumenti di valutazione e monitoraggio per simulare cambiamenti e disturbi esterni, e adottando strategie e misure politiche coerenti a scala locale.Land use change is one of the most important drivers for the reduction of ecosystem resilience, and the loss ofbiodiversity and services provision. This is a peculiar challenge, especially in Mediterranean mountain environments,where abandonment and forest transition phenomena increasingly threaten the forest capacity to provide benefits for local communities. Under these conditions, forest governance is called to balance the landuse change impacts and the health and stability of forest ecosystems, in order to ensure the long-term sustainabilityof such marginal environments. This paper aims at deeper understanding the impacts of land use change on forest ecosystem on mountain environments in Italy. At first, a downscaled review on the conceptsof land use change and ecosystem services provision is carried out. Then, according to the review results, therelationships between adaptive capacity of forest management and planning, and land use change is deeply described. Finally, future-oriented strategies of adaptive governance to face land use change are proposed. Inthe context of land use change, adaptive governance can improve forest resilience through filling the researchgaps between the national and the global contexts, adopting monitoring and assessment tools to simulate external changes and disturbances, and effectively implement consistent policy measures and strategies at localscale

    Inflammatory and Adipose Response in Solid Organ Transplant Recipients After a Marathon Cycling Race

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    Abstract Background Organ transplant recipients frequently have chronic inflammation, with a weighty impact on cardiovascular risk. These patients can benefit from exercise, although the role of intense training is unclear. We evaluated the effect of a 130-km cycling race on inflammatory cytokines and adiponectin levels in transplant recipients. Methods Circulating interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and adiponectin were assayed in 35 healthy subjects vs 19 transplant recipients (10 kidney, 8 liver, 1 heart), matched for sex, age, body mass index, and preparation workout. The determinations were performed before the race, at the end, and after 18 to 24 hours. Baseline values of 32 sedentary transplant recipients also were evaluated to explore the possible chronic impact of lifestyle. Results All cyclists had 6- to 8-fold increased IL-6 levels after the race that decreased, without returning to baseline, the day after. Conversely, serum TNF-α and IFN-γ showed a progressive increase starting during physical performance and enduring for the next 18 to 24 hours in healthy subjects, whereas they were unchanged over time in cyclists with transplants. In transplant recipients who did not perform exercise, all of the analytes were significantly higher in comparison to basal levels of physically active subjects. Conclusions Our data suggest that clinically stable and properly trained transplant recipients can safely perform and progressively benefit from exercise, even at a competitive level. The changes in inflammation parameters were temporary and parallel with those of the healthy subjects. The comparison with sedentary transplant recipients revealed an overall amelioration of inflammatory indexes as a possible effect of regular physical activity on systemic inflammation

    Mechanistic Insights Into the Anticancer Properties of the Auranofin Analog Au(PEt3)I: A Theoretical and Experimental Study

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    Au(PEt3)I (AF-I hereafter), the iodide analog of the FDA-approved drug auranofin (AF hereafter), is a promising anticancer agent that produces its pharmacological effects through interaction with non-genomic targets such as the thioredoxin reductase system. AF-I is endowed with a very favorable biochemical profile showing potent in vitro cytotoxic activity against several cancer types including ovarian and colorectal cancer. Remarkably, in a recent publication, some of us reported that AF-I induces an almost complete and rapid remission in an orthotopic in vivo mouse model of ovarian cancer. The cytotoxic potency does not bring about highly severe side effects, making AF-I very well-tolerated even for higher doses, even more so than the pharmacologically active ones. All these promising features led us to expand our studies on the mechanistic aspects underlying the antitumor activity of AF-I. We report here on an integrated experimental and theoretical study on the reactivity of AF-I, in comparison with auranofin, toward relevant aminoacidic residues or their molecular models. Results point out that the replacement of the thiosugar moiety with iodide significantly affects the overall reactivity toward the amino acid residues histidine, cysteine, methionine, and selenocysteine. Altogether, the obtained results contribute to shed light into the enhanced antitumoral activity of AF-I compared with AF
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