428 research outputs found

    Preliminary checklist of the Italian gypsophilous flora

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    The richness and uniqueness of the flora growing on gypsum substrates in Italy is known since the XIX century (Macchiati, 1888). Furthermore, the concept of plant gypsophily can be defined as the exclusiveness (or virtually exclusiveness) for living in gypsum outcropping rocks. Thus only those plant species, which show preference – or even exclusivity - for gypsum substrates, would be classified as gipsophilous (Mota et al., 2011). The main aim of this research has been the elaboration of a checklist of the Italian gypsophilous flora. The study was made possible through international collaboration between the "Mediterranea" University of Reggio Calabria (Italy) and the University of Almería (Spain). During the first step, an extensive literature review has been carried out in order to collect all available information about gypsophilous flora and to compile a preliminary list. Afterwards 18 regional botanists experts on Italian gypsum flora have been asked to rank the preference of these species for gypsum soils. Following the methodology proposed by Mota et al. (2009), the gypsophilous character of more than 100 plant species has been thus ranked on a scale ranging from 1 to 5 (with 5 representing for a total dependence on gypsum substrates). According to the obtained values, all the plant species, ranking between absolute or preferent gypsophytes, will figure in the final checklist of the gypsophytes of the whole Italian territory

    Emulsion sheet doublets as interface trackers for the OPERA experiment

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    New methods for efficient and unambiguous interconnection between electronic counters and target units based on nuclear photographic emulsion films have been developed. The application to the OPERA experiment, that aims at detecting oscillations between mu neutrino and tau neutrino in the CNGS neutrino beam, is reported in this paper. In order to reduce background due to latent tracks collected before installation in the detector, on-site large-scale treatments of the emulsions ("refreshing") have been applied. Changeable Sheet (CSd) packages, each made of a doublet of emulsion films, have been designed, assembled and coupled to the OPERA target units ("ECC bricks"). A device has been built to print X-ray spots for accurate interconnection both within the CSd and between the CSd and the related ECC brick. Sample emulsion films have been extensively scanned with state-of-the-art automated optical microscopes. Efficient track-matching and powerful background rejection have been achieved in tests with electronically tagged penetrating muons. Further improvement of in-doublet film alignment was obtained by matching the pattern of low-energy electron tracks. The commissioning of the overall OPERA alignment procedure is in progress.Comment: 19 pages, 19 figure

    The detection of neutrino interactions in the emulsion/lead target of the OPERA experiment

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    The OPERA neutrino detector in the underground Gran Sasso Laboratory (LNGS) was designed to perform the first detection of neutrino oscillations in appearance mode through the study of ΜΌ→Μτ\nu_\mu\to\nu_\tau oscillations. The apparatus consists of an emulsion/lead target complemented by electronic detectors and it is placed in the high energy long-baseline CERN to LNGS beam (CNGS) 730 km away from the neutrino source. Runs with CNGS neutrinos were successfully carried out in 2007 and 2008 with the detector fully operational with its related facilities for the emulsion handling and analysis. After a brief description of the beam and of the experimental setup we report on the collection, reconstruction and analysis procedures of first samples of neutrino interaction events

    First events from the CNGS neutrino beam detected in the OPERA experiment

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    The OPERA neutrino detector at the underground Gran Sasso Laboratory (LNGS) was designed to perform the first detection of neutrino oscillations in appearance mode, through the study of nu_mu to nu_tau oscillations. The apparatus consists of a lead/emulsion-film target complemented by electronic detectors. It is placed in the high-energy, long-baseline CERN to LNGS beam (CNGS) 730 km away from the neutrino source. In August 2006 a first run with CNGS neutrinos was successfully conducted. A first sample of neutrino events was collected, statistically consistent with the integrated beam intensity. After a brief description of the beam and of the various sub-detectors, we report on the achievement of this milestone, presenting the first data and some analysis results.Comment: Submitted to the New Journal of Physic

    Towards a checklist of the Italian gypsophilous vascular flora.

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    The strict relationship between plants and particular types of substrate has long been known to botanists and plant ecologists who have dealt with this issue. The peculiar flora growing on Italian gypsum substrates has been underlined since the nineteenth century (1, 2, 3). The concept of plant gypsophily can be defined as the exclusiveness or marked preference for living on gypsum outcropping rocks. Thus, only those plant species which show preference, or even exclusivity, for gypsum substrates, should be classified as gypsophilous (4). The main aim of this research has been to provide a checklist of the Italian gypsophilous flora. The study was made possible through international collaboration between the “Mediterranea” University of Reggio Calabria (Italy) and the University of Almería (Spain). During this first step, an extensive literature review has been carried out in order to collect all available information about Italian gypsophilous flora and to compile a preliminary list. Afterwards 18 regional botanists expert on Italian gypsum flora have been asked to rank the gypsum preference of the species from this preliminary list. Following the methodology proposed by Mota et al. (5), the degree of gypsophily was ranked on a scale from 1 to 5 (corresponding to low and total dependence on gypsum substrates, respectively). The species list was subsequently amended and improved twice on the basis of peer opinions to obtain a final evaluation. More than 360 species have been taken into account. According to the obtained values, all the plant species, ranking between absolute or preferential gypsophytes (with median values between 5 and 3), will figure in the final checklist of the Italian gypsophytes. A more detailed study on the gypsophilous flora and plant communities would be required to support an effective conservation action for the Italian gypsum areas and their natural heritage

    Search for non-Gaussianity in pixel, harmonic and wavelet space: compared and combined

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    We present a comparison between three approaches to test non-Gaussianity of cosmic microwave background data. The Minkowski functionals, the empirical process method and the skewness of wavelet coefficients are applied to maps generated from non-standard inflationary models and to Gaussian maps with point sources included. We discuss the different power of the pixel, harmonic and wavelet space methods on these simulated almost full-sky data (with Planck like noise). We also suggest a new procedure consisting of a combination of statistics in pixel, harmonic and wavelet space.Comment: Accepted for publication in PR

    Current drive at plasma densities required for thermonuclear reactors

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    Progress in thermonuclear fusion energy research based on deuterium plasmas magnetically confined in toroidal tokamak devices requires the development of efficient current drive methods. Previous experiments have shown that plasma current can be driven effectively by externally launched radio frequency power coupled to lower hybrid plasma waves. However, at the high plasma densities required for fusion power plants, the coupled radio frequency power does not penetrate into the plasma core, possibly because of strong wave interactions with the plasma edge. Here we show experiments performed on FTU (Frascati Tokamak Upgrade) based on theoretical predictions that nonlinear interactions diminish when the peripheral plasma electron temperature is high, allowing significant wave penetration at high density. The results show that the coupled radio frequency power can penetrate into high-density plasmas due to weaker plasma edge effects, thus extending the effective range of lower hybrid current drive towards the domain relevant for fusion reactors

    Justified Concern or Exaggerated Fear: The Risk of Anaphylaxis in Percutaneous Treatment of Cystic Echinococcosis—A Systematic Literature Review

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    Percutaneous treatment (PT) emerged in the mid-1980s as an alternative to surgery for selected cases of abdominal cystic echinococcosis (CE). Despite its efficacy and widespread use, the puncture of echinococcal cysts is still far from being universally accepted. One of the main reasons for this reluctance is the perceived risk of anaphylaxis linked to PTs. To quantify the risk of anaphylactic reactions and lethal anaphylaxis with PT, we systematically searched MEDLINE for publications on PT of CE and reviewed the PT-related complications. After including 124 publications published between 1980 and 2010, we collected a total number of 5943 PT procedures on 5517 hepatic and non-hepatic echinococcal cysts. Overall, two cases of lethal anaphylaxis and 99 reversible anaphylactic reactions were reported. Lethal anaphylaxis occurred in 0.03% of PT procedures, corresponding to 0.04% of treated cysts, while reversible allergic reactions complicated 1.7% of PTs, corresponding to 1.8% of treated echinococcal cysts. Analysis of the literature shows that lethal anaphylaxis related to percutaneous treatment of CE is an extremely rare event and is observed no more frequently than drug-related anaphylactic side effects

    Overview of the FTU results

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    Since the 2018 IAEA FEC Conference, FTU operations have been devoted to several experiments covering a large range of topics, from the investigation of the behaviour of a liquid tin limiter to the runaway electrons mitigation and control and to the stabilization of tearing modes by electron cyclotron heating and by pellet injection. Other experiments have involved the spectroscopy of heavy metal ions, the electron density peaking in helium doped plasmas, the electron cyclotron assisted start-up and the electron temperature measurements in high temperature plasmas. The effectiveness of the laser induced breakdown spectroscopy system has been demonstrated and the new capabilities of the runaway electron imaging spectrometry system for in-flight runaways studies have been explored. Finally, a high resolution saddle coil array for MHD analysis and UV and SXR diamond detectors have been successfully tested on different plasma scenarios
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