3,736 research outputs found

    The RISC-KIT storm impact database: A new tool in support of DRR

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    This paper presents a new storm impact database for European coastlines that facilitates the upload, browsing and download of a broad range of physical and impact information related to historical and recent marine storm events. The database is transparent in terms of open access to raw data and metadata, makes use of version control systems through the OpenEarth repository and promotes the use of international standards. A total of 298 storm events are currently stored in the database from the ten RISC-KIT case study sites, including historical events dating back to the sixteenth century. To demonstrate the application of the tool, examples of typical event data contained within the database as well as the ability of the database to identify impacts of events across regions are presented. It is envisaged that this database will expand beyond the ten case study sites, with the aim of promoting and greatly improving the collection and reporting of extreme hydro-meteorological events across Europe into the future

    Approximate Flavor Symmetries in the Lepton Sector

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    Approximate flavor symmetries in the quark sector have been used as a handle on physics beyond the Standard Model. Due to the great interest in neutrino masses and mixings and the wealth of existing and proposed neutrino experiments it is important to extend this analysis to the leptonic sector. We show that in the see-saw mechanism, the neutrino masses and mixing angles do not depend on the details of the right-handed neutrino flavor symmetry breaking, and are related by a simple formula. We propose several ans\"{a}tze which relate different flavor symmetry breaking parameters and find that the MSW solution to the solar neutrino problem is always easily fit. Further, the νμντ\nu_\mu - \nu_\tau oscillation is unlikely to solve the atmospheric neutrino problem and, if we fix the neutrino mass scale by the MSW solution, the neutrino masses are found to be too small to close the Universe.Comment: 12 pages (no figures), LBL-3459

    Controlling trapping potentials and stray electric fields in a microfabricated ion trap through design and compensation

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    Recent advances in quantum information processing with trapped ions have demonstrated the need for new ion trap architectures capable of holding and manipulating chains of many (>10) ions. Here we present the design and detailed characterization of a new linear trap, microfabricated with scalable complementary metal-oxide-semiconductor (CMOS) techniques, that is well-suited to this challenge. Forty-four individually controlled DC electrodes provide the many degrees of freedom required to construct anharmonic potential wells, shuttle ions, merge and split ion chains, precisely tune secular mode frequencies, and adjust the orientation of trap axes. Microfabricated capacitors on DC electrodes suppress radio-frequency pickup and excess micromotion, while a top-level ground layer simplifies modeling of electric fields and protects trap structures underneath. A localized aperture in the substrate provides access to the trapping region from an oven below, permitting deterministic loading of particular isotopic/elemental sequences via species-selective photoionization. The shapes of the aperture and radio-frequency electrodes are optimized to minimize perturbation of the trapping pseudopotential. Laboratory experiments verify simulated potentials and characterize trapping lifetimes, stray electric fields, and ion heating rates, while measurement and cancellation of spatially-varying stray electric fields permits the formation of nearly-equally spaced ion chains.Comment: 17 pages (including references), 7 figure

    ATLAST detector needs for direct spectroscopic biosignature characterization in the visible and near-IR

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    Are we alone? Answering this ageless question will be a major focus for astrophysics in coming decades. Our tools will include unprecedentedly large UV-Optical-IR space telescopes working with advanced coronagraphs and starshades. Yet, these facilities will not live up to their full potential without better detectors than we have today. To inform detector development, this paper provides an overview of visible and near-IR (VISIR; λ=0.41.8 μm\lambda=0.4-1.8~\mu\textrm{m}) detector needs for the Advanced Technology Large Aperture Space Telescope (ATLAST), specifically for spectroscopic characterization of atmospheric biosignature gasses. We also provide a brief status update on some promising detector technologies for meeting these needs in the context of a passively cooled ATLAST.Comment: 8 pages, Presented 9 August 2015 at SPIE Optics + Photonics, San Diego, C

    Can an early-warning system help minimize the impacts of coastal storms? A case study of the 2012 Halloween storm, northern Italy

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    Abstract. The Emilia-Romagna early-warning system (ER-EWS) is a state-of-the-art coastal forecasting system that comprises a series of numerical models (COSMO, ROMS, SWAN and XBeach) to obtain a daily 3-day forecast of coastal storm hazard at eight key sites along the Emilia-Romagna coastline (northern Italy). On the night of 31 October 2012, a major storm event occurred that resulted in elevated water levels (equivalent to a 1-in-20- to 1-in-50-year event) and widespread erosion and flooding. Since this storm happened just 1 month prior to the roll-out of the ER-EWS, the forecast performance related to this event is unknown. The aim of this study was to therefore reanalyse the ER-EWS as if it had been operating a day before the event and determine to what extent the forecasts may have helped reduce storm impacts. Three different reanalysis modes were undertaken: (1) a default forecast (DF) mode based on 3-day wave and water-level forecasts and default XBeach parameters; (2) a measured offshore (MO) forecast mode using wave and water-level measurements and default XBeach parameters; and (3) a calibrated XBeach (CX) mode using measured boundary conditions and an optimized parameter set obtained through an extensive calibration process. The results indicate that, while a "code-red" alert would have been issued for the DF mode, an underprediction of the extreme water levels of this event limited high-hazard forecasts to only two of the eight ER-EWS sites. Forecasts based on measured offshore conditions (the MO mode) more-accurately indicate high-hazard conditions for all eight sites. Further considerable improvements are observed using an optimized XBeach parameter set (the CX mode) compared to default parameters. A series of what-if scenarios at one of the sites show that artificial dunes, which are a common management strategy along this coastline, could have hypothetically been constructed as an emergency procedure to potentially reduce storm impacts

    Molecular basis for functional switching of GFP by two disparate non-native post-translational modifications of a phenyl azide reaction handle

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    Through the genetic incorporation of a single phenyl azide group into superfolder GFP (sfGFP) at residue 148 we provide a molecular description of how this highly versatile chemical handle can be used to positively switch protein function in vitro and in vivo via either photochemistry or bioconjugation. Replacement of H148 with p-azido-L-phenylalanine (azF) blue shifts the major excitation peak ∼90 nm by disrupting the H-bond and proton transfer network that defines the chromophore charged state. Bioorthogonal click modification with a simple dibenzylcyclooctyne or UV irradiation shifts the neutral-anionic chromophore equilibrium, switching fluorescence to the optimal ∼490 nm excitation. Click modification also improved quantum yield over both the unmodified and original protein. Crystal structures of both the click modified and photochemically converted forms show that functional switching is due to local conformational changes that optimise the interaction networks surrounding the chromophore. Crystal structure and mass spectrometry studies of the irradiated protein suggest that the phenyl azide converts to a dehydroazepine and/or an azepinone. Thus, protein embedded phenyl azides can be used beyond simple photocrosslinkers and passive conjugation handles, and mimic many natural post-translational modifications: modulation though changes in interaction networks

    Open Access Publishing in Business Research: The Authors’ Perspective

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    Open access (OA) publishing is now accepted as an integral part of the emerging trends within scholarly communication. Business librarians, like their subject specialist colleagues in other disciplines, are increasingly called upon to interpret scholarly communication trends to their faculty. This study surveys 1,293 business faculty from American schools of business accredited by the Association to Advance Collegiate Schools of Business. Issues explored include business faculty publishing practices within the discipline and how these affect academic advancement, obtaining articles for their own research, electronic publishing, self-archiving, and their perceptions about OA publishing generally.With support from the Emerald Publishing Research Award 2009

    Loudly sing cuckoo : More-than-human seasonalities in Britain

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    This research was funded by a grant from the Arts and Humanities Research Council, grant number AH/E009573/1.Peer reviewedPostprin
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