1,423 research outputs found

    Relative Sea-Level Rise Projections and Flooding Scenarios for 2150 CE for the Island of Ustica (Southern Tyrrhenian Sea, Italy)

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    The island of Ustica (Italy) is constantly exposed to the effects of sea-level rise, which is threatening its coastal zone. With the aim of assessing the sea levels that are anticipated by 2150 CE under the climatic projections shown in the AR6 report from the IPCC, a detailed evaluation of potential coastal flooding under different climatic scenarios and the ongoing land subsidence has been carried out for three coastal zones. Scenarios are based on the determination of the current coastline position, a high-resolution digital terrain and marine model, and the SSP1-2.6, SSP3-7.0, and SSP5-8.5 climatic projections. Relative sea-level rise projections allowed the mapping of the potential inundated surfaces for 2030, 2050, 2100, and 2150. The results show rising sea levels for 2150, ranging from a minimum of 66 ± 40 cm (IPCC AR6 SSP2.6 scenario) to a maximum of 128 ± 52 cm (IPCC AR6 SSP8.5 scenario). In such conditions, considering the SSP8.5 scenario during storm surges with return times (RTs) of 1 and 100 years, the expected maximum wave run-up along the island may vary from 3 m (RT = 1) to 14 m (RT = 100), according to the coastal morphology. Our results show that adaptation and mitigation actions are required to protect the touristic and harbor installations of the island

    The AllWISE Motion Survey, Part 2

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    We use the AllWISE Data Release to continue our search for WISE-detected motions. In this paper, we publish another 27,846 motion objects, bringing the total number to 48,000 when objects found during our original AllWISE motion survey are included. We use this list, along with the lists of confirmed WISE-based motion objects from the recent papers by Luhman and by Schneider et al. and candidate motion objects from the recent paper by Gagne et al. to search for widely separated, common-proper-motion systems. We identify 1,039 such candidate systems. All 48,000 objects are further analyzed using color-color and color-mag plots to provide possible characterizations prior to spectroscopic follow-up. We present spectra of 172 of these, supplemented with new spectra of 23 comparison objects from the literature, and provide classifications and physical interpretations of interesting sources. Highlights include: (1) the identification of three G/K dwarfs that can be used as standard candles to study clumpiness and grain size in nearby molecular clouds because these objects are currently moving behind the clouds, (2) the confirmation/discovery of several M, L, and T dwarfs and one white dwarf whose spectrophotometric distance estimates place them 5-20 pc from the Sun, (3) the suggestion that the Na 'D' line be used as a diagnostic tool for interpreting and classifying metal-poor late-M and L dwarfs, (4) the recognition of a triple system including a carbon dwarf and late-M subdwarf, for which model fits of the late-M subdwarf (giving [Fe/H] ~ -1.0) provide a measured metallicity for the carbon star, and (5) a possible 24-pc-distant K5 dwarf + peculiar red L5 system with an apparent physical separation of 0.1 pc.Comment: 62 pages with 80 figures, accepted for publication in The Astrophysical Journal Supplement Series, 23 Mar 2016; second version fixes a few small typos and corrects the footnotes for Table

    D^* production from e^+e^- to ep collisions in NLO QCD

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    Fragmentation functions for D mesons, based on the convolution of a perturbative part, related to the heavy quark perturbative showering, and a non-perturbative model for its hadronization into the meson, are used to describe D^* production in e^+e^- and ep collisions. The non-perturbative part is determined by fitting the e^+e^- data taken by ARGUS and OPAL at 10.6 and 91.2 GeV respectively. When fitting with a non perturbative Peterson fragmentation function and using next-to-leading evolution for the perturbative part, we find an epsilon parameter sensibly different from the one commonly used, which is instead found with a leading order fit. The use of this new value is shown to increase considerably the cross section for D^* production at HERA, suggesting a possible reconciliation between the next-to-leading order theoretical predictions and the experimental data.Comment: 20 pages, LaTeX2e, 8 Postscript figure

    Total photoproduction cross-section at very high energy

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    In this paper we apply to photoproduction total cross-section a model we have proposed for purely hadronic processes and which is based on QCD mini-jets and soft gluon re-summation. We compare the predictions of our model with the HERA data as well as with other models. For cosmic rays, our model predicts substantially higher cross-sections at TeV energies than models based on factorization but lower than models based on mini-jets alone, without soft gluons. We discuss the origin of this difference.Comment: 13 pages, 9 figures. Accepted for publication in EPJC. Changes concern added references, clarifications of the Soft Gluon Resummation method used in the paper, and other changes requested by the Journal referee which do not change the results of the original versio

    QCD factorization for forward hadron scattering at high energies

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    We consider the QCD factorization of DIS structure functions at small x and amplitudes of 2->2 -hadronic forward scattering at high energy. We show that both collinear and k_T-factorization for these processes can be obtained approximately as reductions of a more general (totally unintegrated) form of the factorization. The requirement of ultraviolet and infrared stability of the factorization convolutions allows us to obtain restrictions on the fits for the parton distributions in k_T- and collinear factorization.Comment: 18 pages, 10 figures In the present version misprints found in the prevcious version are corrected and some more details are explaine

    CAMEMBERT: A Mini-Neptunes GCM Intercomparison, Protocol Version 1.0. A CUISINES Model Intercomparison Project

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    With an increased focus on the observing and modelling of mini-Neptunes, there comes a need to better understand the tools we use to model their atmospheres. In this paper, we present the protocol for the CAMEMBERT (Comparing Atmospheric Models of Extrasolar Mini-neptunes Building and Envisioning Retrievals and Transits) project, an intercomparison of general circulation models (GCMs) used by the exoplanetary science community to simulate the atmospheres of mini-Neptunes. We focus on two targets well studied both observationally and theoretically with planned JWST Cycle 1 observations: the warm GJ~1214b and the cooler K2-18b. For each target, we consider a temperature-forced case, a clear sky dual-grey radiative transfer case, and a clear sky multi band radiative transfer case, covering a range of complexities and configurations where we know differences exist between GCMs in the literature. This paper presents all the details necessary to participate in the intercomparison, with the intention of presenting the results in future papers. Currently, there are eight GCMs participating (ExoCAM, Exo-FMS, FMS PCM, Generic PCM, MITgcm, RM-GCM, THOR, and the UM), and membership in the project remains open. Those interested in participating are invited to contact the authors.Comment: Accepted to PS

    The General Practice Assessment Questionnaire (GPAQ) – Development and psychometric characteristics

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    <p>Abstract</p> <p>Background</p> <p>Continual quality improvement in primary care is an international priority. In the United Kingdom, the major initiative for improving quality of care is the Quality and Outcomes Framework (QoF) of the 2004 GP contract. Although the primary focus of the QoF is on clinical care, it is acknowledged that a comprehensive assessment of quality also requires valid and reliable measurement of the patient perspective, so financial incentives are included in the contract for general practices to survey patients' views. One questionnaire specified for use in the QoF is the General Practice Assessment Questionnaire (GPAQ). This paper describes the development of the GPAQ (with post-consultation and postal versions) and presents a preliminary examination of the psychometric properties of the questionnaire.</p> <p>Methods</p> <p>Description of scale development and preliminary analysis of psychometric characteristics (internal reliability, factor structure), based on a large dataset of routinely collected GPAQ surveys (n = 190,038 responses to the consultation version of GPAQ and 20,309 responses to the postal version) from practices in the United Kingdom during the 2005–6 contract year.</p> <p>Results</p> <p>Respondents tend to report generally favourable ratings. Responses were particularly skewed on the GP communication scale, though no more so than for other questionnaires in current use in the UK for which data were available. Factor analysis identified 2 factors that clearly relate to core concepts in primary care quality ('access' and 'interpersonal care') that were common to both version of the GPAQ. The other factors related to 'enablement' in the post-consultation version and 'nursing care' in the postal version.</p> <p>Conclusion</p> <p>This preliminary evaluation indicates that the scales of the GPAQ are internally reliable and that the items demonstrate an interpretable factor structure. Issues concerning the distributions of GPAQ responses are discussed. Potential further developments of the item content for the GPAQ are also outlined.</p
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