261 research outputs found

    Hydrogeological model and hydraulic behaviour of a large landslide in the Italian Western Alps

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    Abstract. A study of the large, deep-seated Rosone landslide (Italian Western Alps) is presented. A large amount of geological and geomechanical data has been collected in this area, due to the presence of various villages and man-made structures, and an automatic monitoring system was installed in December 2000. Since its installation, this system has been showing a continuous slow movement with periodical accelerations that can be correlated to heavy rainfall events. A hydrogeological model has been developed to study the influence of rainfall events on the pore pressure variations inside the rock slope. The structural characteristics, inclinometric and piezometric measurements, statigraphic and seismic profiles, geomorphologic information, water balance and chemical analyses of the main springs in the slope have been taken into account to consider this problem. A numerical hydraulic investigation, based on a continuum equivalent model of the landslide, has then been carried out using the FLAC3D computer code. Some preliminary results, which highlight the role of permeability and the porosity values of the rock mass on the pore pressure variations during heavy rainfall, are shown in the paper

    Corrigendum to “Recent changes in primary production and phytoplankton in the offshore region of southeastern Lake Michigan” [J. Great Lakes Res. 36 (Supplement 3) (2010) 20–29]

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    The authors regret that there is an error on the labels of two figures that were published in the paper referenced above. For Figs. 5b, c, and d and 7b and c the y-axes have the wrong labels. The following are the correct y-axis labels: Fig. 5b — the y-axis should range from 0 to 5, Fig. 5c — the y-axis should range from 0 to 2, Fig. 5d — the y-axis label should range from 0 to 3, Fig. 7b — the y-axis should range from 0 to 40, and for Fig. 7c — the y-axis should range from 0 to 50

    Corrigendum to “Recent changes in primary production and phytoplankton in the offshore region of southeastern Lake Michigan” [J. Great Lakes Res. 36 (Supplement 3) (2010) 20–29]

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    The authors regret that there is an error on the labels of two figures that were published in the paper referenced above. For Figs. 5b, c, and d and 7b and c the y-axes have the wrong labels. The following are the correct y-axis labels: Fig. 5b — the y-axis should range from 0 to 5, Fig. 5c — the y-axis should range from 0 to 2, Fig. 5d — the y-axis label should range from 0 to 3, Fig. 7b — the y-axis should range from 0 to 40, and for Fig. 7c — the y-axis should range from 0 to 50

    Mechanisms of Surviving Burial: Dune Grass Interspecific Differences Drive Resource Allocation After Sand Deposition

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    Sand dunes are important geomorphic formations of coastal ecosystems that are critical in protecting human populations that live in coastal areas. Dune formation is driven by ecomorphodynamic interactions between vegetation and sediment deposition. While there has been extensive research on responses of dune grasses to sand burial, there is a knowledge gap in understanding mechanisms of acclimation between similar, coexistent, dune-building grasses such as Ammophila breviligulata (C3), Spartina patens (C4), and Uniola paniculata (C4). Our goal was to determine how physiological mechanisms of acclimation to sand burial vary between species. We hypothesize that (1) in the presence of burial, resource allocation will be predicated on photosynthetic pathway and that we will be able to characterize the C3 species as a root allocator and the C4 species as leaf allocators. We also hypothesize that (2) despite similarities between these species in habitat, growth form, and life history, leaf, root, and whole plant traits will vary between species when burial is not present. Furthermore, when burial is present, the existing variability in physiological strategy will drive species-specific mechanisms of survival. In a greenhouse experiment, we exposed three dune grass species to different burial treatments: 0 cm (control) and a one-time 25-cm burial to mimic sediment deposition during a storm. At the conclusion of our study, we collected a suite of physiological and morphological functional traits. Results showed that Ammophila decreased allocation to aboveground biomass to maintain root biomass, preserving photosynthesis by allocating nitrogen (N) into light-exposed leaves. Conversely, Uniola and Spartina decreased allocation to belowground production to increase elongation and maintain aboveground biomass. Interestingly, we found that species were functionally distinct when burial was absent; however, all species became more similar when treated with burial. In the presence of burial, species utilized functional traits of rapid growth strategy, although mechanisms of change were interspecifically variable

    Community incidence of pathogen-specific gastroenteritis: reconstructing the surveillance pyramid for seven pathogens in seven European Union member states.

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    By building reconstruction models for a case of gastroenteritis in the general population moving through different steps of the surveillance pyramid we estimated that millions of illnesses occur annually in the European population, leading to thousands of hospitalizations. We used data on the healthcare system in seven European Union member states in relation to pathogen characteristics that influence healthcare seeking. Data on healthcare usage were obtained by harmonized cross-sectional surveys. The degree of under-diagnosis and underreporting varied by pathogen and country. Overall, underreporting and under-diagnosis were estimated to be lowest for Germany and Sweden, followed by Denmark, The Netherlands, UK, Italy and Poland. Across all countries, the incidence rate was highest for Campylobacter spp. and Salmonella spp. Incidence estimates resulting from the pyramid reconstruction approach are adjusted for biases due to different surveillance systems and are therefore a better basis for international comparisons than reported data

    Estimating the incidence of acute infectious intestinal disease in the community in the UK:A retrospective telephone survey

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    Objectives: To estimate the burden of intestinal infectious disease (IID) in the UK and determine whether disease burden estimations using a retrospective study design differ from those using a prospective study design. Design/Setting: A retrospective telephone survey undertaken in each of the four countries comprising the United Kingdom. Participants were randomly asked about illness either in the past 7 or 28 days. Participants: 14,813 individuals for all of whom we had a legible recording of their agreement to participate Outcomes: Self-reported IID, defined as loose stools or clinically significant vomiting lasting less than two weeks, in the absence of a known non-infectious cause. Results: The rate of self-reported IID varied substantially depending on whether asked for illness in the previous 7 or 28 days. After standardising for age and sex, and adjusting for the number of interviews completed each month and the relative size of each UK country, the estimated rate of IID in the 7-day recall group was 1,530 cases per 1,000 person-years (95% CI: 1135 – 2113), while in the 28-day recall group it was 533 cases per 1,000 person-years (95% CI: 377 – 778). There was no significant variation in rates between the four countries. Rates in this study were also higher than in a related prospective study undertaken at the same time. Conclusions: The estimated burden of disease from IID varied dramatically depending on study design. Retrospective studies of IID give higher estimates of disease burden than prospective studies. Of retrospective studies longer recall periods give lower estimated rates than studies with short recall periods. Caution needs to be exercised when comparing studies of self-reported IID as small changes in study design or case definition can markedly affect estimated rates

    Light harvesting of CdSe/CdS quantum dots coated with β-cyclodextrin based host–guest species through resonant energy transfer from the guests

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    Films of nano-hybrids based on red emitting CdSe/CdS QDs functionalized with perthiolated \u3b2-cyclodextrin hosting a green emitting nitrobenzoxadiazole derivative show emission harvested by the host\u2013guest organic system through resonant energy transfer from the organic host\u2013guest species to the QD
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