330 research outputs found

    DTM-based morphometry of the Palinuro seamount (Eastern Tyrrhenian Sea): Geomorphological and volcanological implications

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    We present a high resolution DTM of the Palinuro Seamount (PS, Tyrrhenian Sea, Italy) resulting from the processing of multibeam swath bathymetry records acquired during the second leg of the ā€œAeolian 2007ā€ cruise. PS consists of several superimposed volcanoes aligned along a N100Ā°E strike and measures 55Ɨ25 km. The western and the central sectors result from the coalescence of collapse structures (calderas) with younger volcanic cones. The eastern sector reveals a more complex and articulated structure. In the central sector, a volcanic crater with a well-preserved rim not obliterated by erosional events suggests a volcanological rejuvenation of this sector. The presence of flat surfaces on the top of the seamount may be due to the formation of marine terraces during the last sea-level lowering. Lateral collapses on the northern and southern flanks of the seamount are probably related to slope instability, as suggested by the presence of steep slopes (25ā€“40Ā°). The main fault affecting PS strikes N65Ā°E and shows a right lateral component of movement. Eā€“W and N10Ā°E striking faults are also present. Assuming that theN100Ā°E deep-seated fault,which is responsible for theemplacement of PS,movedwith sinistral slips, we interpret the N65Ā°E and the N10Ā°E faults as right-lateral (second order) shear and left-lateral (third order) shear, respectively. Due to the particular location of the Palinuro Seamount, the data presented here allow us to better understand the volcanism and the geodynamic processes of the Tyrrhenian Sea

    Bicovariant Quantum Algebras and Quantum Lie Algebras

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    A bicovariant calculus of differential operators on a quantum group is constructed in a natural way, using invariant maps from \fun\ to \uqg\ , given by elements of the pure braid group. These operators --- the `reflection matrix' Yā‰”L+SLāˆ’Y \equiv L^+ SL^- being a special case --- generate algebras that linearly close under adjoint actions, i.e. they form generalized Lie algebras. We establish the connection between the Hopf algebra formulation of the calculus and a formulation in compact matrix form which is quite powerful for actual computations and as applications we find the quantum determinant and an orthogonality relation for YY in SOq(N)SO_q(N).Comment: 38 page

    Rapporto sullā€™attivitĆ  29 Giugno ā€“ 6 Luglio 2013

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    In questo lavoro viene descritta la campagna geofisica e idro-oceanografica ā€˜GARGANO2013ā€™ effettuata grazie ad una collaborazione tra INGV e Marina Militare Italiana nellā€™ambito di un accordo di collaborazione denominato CONAGEM (Coordinamento Nazionale per la Geofisica Marina). Tale accordo, siglato nel 2005 fra i principali enti pubblici di ricerca che operano in mare, prevede infatti la possibilitĆ  di attuare congiuntamente campagne di ricerca marine condividendone dati e risultati. La campagna ĆØ stata organizzata con la finalitĆ  di raccogliere quanti piĆ¹ possibili elementi utili a caratterizzare lā€™area marina del Gargano sotto un profilo ambientale predisponendone un quadro di riferimento per successive attivitĆ  di monitoraggio delle fenomenologie presenti nellā€™area di indagine. In questā€™ottica, lā€™obiettivo prefissato era la mappatura di eventuali affioramenti di acque dolci in mare. Contestualmente, ĆØ stata eseguita la sperimentazione di prototipi strumentali per future applicazioni a bordo nave: in particolare, sono state eseguite misure di tipo accelerometrico al fine di caratterizzare le sollecitazioni dinamiche cui sono sottoposti gli strumenti a bordonave ottenendo cosƬ utili informazioni per lo sviluppo di nuove tecnologie quali piattaforme inerziali per uso scientifico e strumentazione per prospezioni gravimetriche da utilizzare su nave

    Treatment of post-cholecystectomy biliary strictures with fully-covered self-expanding metal stents - results after 5ā€‰years of follow-up

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    BACKGROUND: Endoscopic treatment of post-cholecystectomy biliary strictures (PCBS) with multiple plastic biliary stents placed sequentially is a minimally invasive alternative to surgery but requires multiple interventions. Temporary placement of a single fully-covered self-expanding metal stent (FCSEMS) may offer safe and effective treatment with fewer re-interventions. Long-term effectiveness of treatment with FCSEMS to obtain PCBS resolution has not yet been studied. METHODS: In this prospective multi-national study in patients with symptomatic benign biliary strictures (Nā€‰=ā€‰187) due to various etiologies received a FCSEMS with scheduled removal at 6-12ā€‰months and were followed for 5ā€‰years. We report here long-term outcomes of the subgroup of patients with PCBS (Nā€‰=ā€‰18). Kaplan Meier analyses assessed long-term freedom from re-stenting. Adverse events were documented. RESULTS: Endoscopic removal of the FCSEMS was achieved in 83.3% (15/18) of patients after median indwell of 10.9 (range 0.9-13.8) months. In the remaining 3 patients (16.7%), the FCSEMS spontaneously migrated and passed without complications. At the end of FCSEMS indwell, 72% (13/18) of patients had stricture resolution. At 5ā€‰years after FCSEMS removal, 84.6% (95% CI 65.0-100.0%) of patients who had stricture resolution at FCSEMS removal remained stent-free. In addition, at 75ā€‰months after FCSEMS placement, the probability of remaining stent-free was 61.1% (95% CI 38.6-83.6%) for all patients. Stent or removal related serious adverse events occurred in 38.9% (7/18) all resolved without sequalae. CONCLUSIONS: In patients with symptomatic PCBS, temporary placement of a single FCSEMS intended for 10-12ā€‰months indwell is associated with long-term stricture resolution up to 5ā€‰years. Temporary placement of a single FCSEMS may be considered for patients with PCBS not involving the main hepatic confluence. TRIAL REGISTRATION NUMBERS: NCT01014390; CTRI/2012/12/003166; Registered 17 November 2009

    Four Lessons in Versatility or How Query Languages Adapt to the Web

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    Exposing not only human-centered information, but machine-processable data on the Web is one of the commonalities of recent Web trends. It has enabled a new kind of applications and businesses where the data is used in ways not foreseen by the data providers. Yet this exposition has fractured the Web into islands of data, each in different Web formats: Some providers choose XML, others RDF, again others JSON or OWL, for their data, even in similar domains. This fracturing stifles innovation as application builders have to cope not only with one Web stack (e.g., XML technology) but with several ones, each of considerable complexity. With Xcerpt we have developed a rule- and pattern based query language that aims to give shield application builders from much of this complexity: In a single query language XML and RDF data can be accessed, processed, combined, and re-published. Though the need for combined access to XML and RDF data has been recognized in previous work (including the W3Cā€™s GRDDL), our approach differs in four main aspects: (1) We provide a single language (rather than two separate or embedded languages), thus minimizing the conceptual overhead of dealing with disparate data formats. (2) Both the declarative (logic-based) and the operational semantics are unified in that they apply for querying XML and RDF in the same way. (3) We show that the resulting query language can be implemented reusing traditional database technology, if desirable. Nevertheless, we also give a unified evaluation approach based on interval labelings of graphs that is at least as fast as existing approaches for tree-shaped XML data, yet provides linear time and space querying also for many RDF graphs. We believe that Web query languages are the right tool for declarative data access in Web applications and that Xcerpt is a significant step towards a more convenient, yet highly efficient data access in a ā€œWeb of Dataā€

    Rapporto sullā€™attivitĆ  29 Giugno ā€“ 6 Luglio 2013

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    In questo lavoro viene descritta la campagna geofisica e idro-oceanografica ā€˜GARGANO2013ā€™ effettuata grazie ad una collaborazione tra INGV e Marina Militare Italiana nellā€™ambito di un accordo di collaborazione denominato CONAGEM (Coordinamento Nazionale per la Geofisica Marina). Tale accordo, siglato nel 2005 fra i principali enti pubblici di ricerca che operano in mare, prevede infatti la possibilitĆ  di attuare congiuntamente campagne di ricerca marine condividendone dati e risultati. La campagna ĆØ stata organizzata con la finalitĆ  di raccogliere quanti piĆ¹ possibili elementi utili a caratterizzare lā€™area marina del Gargano sotto un profilo ambientale predisponendone un quadro di riferimento per successive attivitĆ  di monitoraggio delle fenomenologie presenti nellā€™area di indagine. In questā€™ottica, lā€™obiettivo prefissato era la mappatura di eventuali affioramenti di acque dolci in mare. Contestualmente, ĆØ stata eseguita la sperimentazione di prototipi strumentali per future applicazioni a bordo nave: in particolare, sono state eseguite misure di tipo accelerometrico al fine di caratterizzare le sollecitazioni dinamiche cui sono sottoposti gli strumenti a bordonave ottenendo cosƬ utili informazioni per lo sviluppo di nuove tecnologie quali piattaforme inerziali per uso scientifico e strumentazione per prospezioni gravimetriche da utilizzare su nave.Marina Militare ItalianaPublished1-283A. Ambiente MarinoN/A or not JCRope

    Smart investments in sustainable food production: revisiting mixed crop-livestock systems

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    Farmers in mixed crop-livestock systems produce about half of the worldā€™s food. In small holdings around the world, livestock are reared mostly on grass, browse, and nonfood biomass from maize, millet, rice, and sorghum crops and in their turn supply manure and traction for future crops. Animals act as insurance against hard times and supply farmers with a source of regular income from sales of milk, eggs, and other products. Thus, faced with population growth and climate change, small-holder farmers should be the first target for policies to intensify production by carefully managed inputs of fertilizer, water, and feed to minimize waste and environmental impact, supported by improved access to markets, new varieties, and technologies

    Genome-wide analyses identify a role for SLC17A4 and AADAT in thyroid hormone regulation.

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    Thyroid dysfunction is an important public health problem, which affects 10% of the general population and increases the risk of cardiovascular morbidity and mortality. Many aspects of thyroid hormone regulation have only partly been elucidated, including its transport, metabolism, and genetic determinants. Here we report a large meta-analysis of genome-wide association studies for thyroid function and dysfunction, testing 8 million genetic variants in up to 72,167 individuals. One-hundred-and-nine independent genetic variants are associated with these traits. A genetic risk score, calculated to assess their combined effects on clinical end points, shows significant associations with increased risk of both overt (Graves' disease) and subclinical thyroid disease, as well as clinical complications. By functional follow-up on selected signals, we identify a novel thyroid hormone transporter (SLC17A4) and a metabolizing enzyme (AADAT). Together, these results provide new knowledge about thyroid hormone physiology and disease, opening new possibilities for therapeutic targets
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