4,250 research outputs found
Sintesi monografica delle risorse idriche sotterranee della Sardegna
L'attenta analisi di tutti i parametri che concorrono alla stesura di un
bilancio idrico, ha come facile conseguenza l'individuazione in quella regione
della possibile presenza di acqua nel sottosuolo la cui consistenza
può essere definita attraverso ulteriori parametri, soprattutto di tipo geofisico,
che ci consentono la valutazione geometrica dei suoi acquiferi.
Nel 1979 l'Istituto di Mineralogia e Geologia ha svolto un'indagine per
conto della Cassa per il Mezzogiorno allo scopo di .individuare. aree di interesse
idrogeologico e pertanto possibili risorse idriche da poter utilizzare
in tempi brevi. .
Il lavoro che interessa tutta la Sardegna è stato condotto attraverso
quattro fasi distinte:
A - Analisi del territorio e sua ripartizione in bacini idrografici e idrogeologici;
B - Esame degli afflussi;
C - Esame dei deflussi;
D - Ipotesi di bilancio delle acque sotterranee per unità idrografica
Repurposing Ketamine in Depression and Related Disorders: Can This Enigmatic Drug Achieve Success?
Repurposing ketamine in the therapy of depression could well represent a breakthrough in understanding the etiology of depression. Ketamine was originally used as an anesthetic drug and later its use was extended to other therapeutic applications such as analgesia and the treatment of addiction. At the same time, the abuse of ketamine as a recreational drug has generated a concern for its psychotropic and potential long-term effects; nevertheless, its use as a fast acting antidepressant in treatment-resistant patients has boosted the interest in the mechanism of action both in psychiatry and in the wider area of neuroscience. This article provides a comprehensive overview of the actions of ketamine and intends to cover: (i) the evaluation of its clinical use in the treatment of depression and suicidal behavior; (ii) the potential use of ketamine in pediatrics; (iii) a description of its mechanism of action; (iv) the involvement of specific brain areas in producing antidepressant effects; (v) the potential interaction of ketamine with the hypothalamic-pituitary-adrenal axis; (vi) the effect of ketamine on neuronal transmission in the bed nucleus of stria terminalis and on its output; (vii) the evaluation of any gender-dependent effects of ketamine; (viii) the interaction of ketamine with the inflammatory processes involved in depression; (ix) the evaluation of the effects observed with single or repeated administration; (x) a description of any adverse or cognitive effects and its abuse potential. Finally, this review attempts to assess whether ketamine’s use in depression can improve our knowledge of the etiopathology of depression and whether its therapeutic effect can be considered an actual cure for depression rather than a therapy merely aimed to control the symptoms of depression
A new scheme for sulphur dioxide retrieval from IASI measurements: application to the Eyjafjallajökull eruption of April and May 2010
A new optimal estimation algorithm for the retrieval of sulphur dioxide (SO<sub>2</sub>) has been developed for the Infrared Atmospheric Sounding Interferometer (IASI) using the channels between 1000–1200 and 1300–1410 cm<sup>−1</sup>. These regions include the two SO<sub>2</sub> absorption bands centred at about 8.7 and 7.3 &mu;m (the &nu;<sub>1</sub> and &nu;<sub>3</sub> bands respectively). The retrieval assumes a Gaussian SO<sub>2</sub> profile and returns the SO<sub>2</sub> column amount in Dobson units and the altitude of the plume in millibars (mb). Forward modelled spectra (against which the measurements are compared) are based on the Radiative Transfer for TOVS (RTTOV) code. In our implementation RTTOV uses atmospheric profiles from European Centre for Medium-Range Weather Forecasts (ECMWF) meteorological data. The retrieval includes a comprehensive error budget for every pixel derived from an error covariance matrix that is based on the SO<sub>2</sub>-free climatology of the differences between the IASI and forward modelled spectra. The IASI forward model includes the ability to simulate a cloud or ash layer in the atmosphere. This feature is used to illustrate that: (1) the SO<sub>2</sub> retrieval is not affected by underlying cloud but is affected if the SO<sub>2</sub> is within or below a cloud layer; (2) it is possible to discern if ash (or other atmospheric constituents not considered in the error covariance matrix) affects the retrieval using quality control based on the fit of the measured spectrum by the forward modelled spectrum. In this work, the algorithm is applied to follow the behaviour of SO<sub>2</sub> plumes from the Eyjafjallajökull eruption during April and May 2010. From 14 April to 4 May (during Phase I and II of the eruption) the total amount of SO<sub>2</sub> present in the atmosphere, estimated by IASI measurements, is generally below 0.02 Tg. During the last part of the eruption (Phase III) the values are an order of magnitude higher, with a maximum of 0.18 Tg measured on the afternoon of 7 May
Front-end Electronics Test for the LHCb Muon Wire Chambers
This document describes the apparatus and procedures implemented to test Multi Wire Proportional Chambers (MWPC) after front-end assembly for the LHCb Muon Detector. Results of measurements of key noise parameters are also described. Given a fully equipped chamber, this system is able to diagnose every channel performing an analysis of front-end output drivers’ response and noise rate versus threshold. Besides, it allows to assess if the noise rate at the experiment threshold region is within appropriate limits. Aiming at an automatic, fast and user-friendly system for mass production tests of MWPC, the project has foreseen as well electronic identification of every chamber and front-end board, and data archiving in such a way to make it available to the Experiment Control System (ECS) while in operation
First results from an aging test of a prototype RPC for the LHCb Muon System
Recent results of an aging test performed at the CERN Gamma Irradiation
Facility on a single--gap RPC prototype developed for the LHCb Muon System are
presented. The results are based on an accumulated charge of about 0.45
C/cm, corresponding to about 4 years of LHCb running at the highest
background rate. The performance of the chamber has been studied under several
photon flux values exploiting a muon beam. A degradation of the rate capability
above 1 kHz/cm is observed, which can be correlated to a sizeable increase
of resistivity of the chamber plates. An increase of the chamber dark current
is also observed. The chamber performance is found to fulfill the LHCb
operation requirements.Comment: 6 pages, 9 figures, presented at the International Workshop on Aging
Phenomena in Gaseous Detectors'', DESY-Hamburg (Germany), October 200
Preliminary results of an aging test of RPC chambers for the LHCb Muon System
The preliminary results of an aging test performed at the CERN Gamma
Irradiation Facility on a single--gap RPC prototype developed for the LHCb Muon
System are presented. The results are based on an accumulated charge density of
0.42 C/cm^2, corresponding to about 4 years of LHCb running at the highest
background rate. We observe a rise in the dark current and noise measured with
source off. The current drawn with source on steadily decreased, possibly
indicating an increase of resistivity of the chamber plates. The performance of
the chamber, studied with a muon beam under several photon flux values, is
found to still fulfill the LHCb operation requirements.Comment: 4 pages, 6 figures, presented at RPC2001, VIth Workshop on Resistive
Plate Chambers and Related Detectors, November 26-27 2001, Coimbra, Portuga
New diagnostic SNP molecular markers for the Mytilus species complex
The development of diagnostic markers has been a long-standing interest of population geneticists as it allows clarification of taxonomic uncertainties. Historically, there has been much debate on the taxonomic status of species belonging to the Mytilus species complex (M. edulis, M. galloprovincialis and M. trossulus), and whether they are discrete species. We analysed reference pure specimens of M. edulis, M. galloprovincialis and M. trossulus, using Restriction site associated DNA (RAD) sequencing and identified over 6,000 SNP markers separating the three species unambiguously. We developed a panel of diagnostic SNP markers for the genotyping of Mytilus species complex as well as the identification of hybrids and interspecies introgression events in Mytilus species. We validated a panel of twelve diagnostic SNP markers which can be used for species genotyping. Being able to accurately identify species and hybrids within the Mytilus species complex is important for the selective mussel stock management, the exclusion of invasive species, basic physiology and bio-diversity studies
A two-step parallel plate chamber with a resistive germanium anode and a two dimensional readout for the detection of minimum ionizing particles
Abstract A parallel plate avalanche chamber specially suited for the high resolution detection of minimum ionizing particles (m.i.p.) is presented. The anode is made of a thin germanium layer with a sheet resistivity > 1 M Ω/p[ while the cathode is made of a nickel mesh having 600 line pairs/in. A chess board of pads placed behind the anode plane is used to obtain the positional information. A 100% detection efficiency, a 40 ns (fwhm) time resolution and a spatial resolution better than 140 μm (fwhm) for both coordinates have been measured
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