224 research outputs found

    Assessing seismic efficiency from scalar Moment-rates: an application to Mt. Etna volcano (Italy)

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    Here we propose an improved estimation of the scalar seismic (from instrumental and historical catalogues), geodetic and geologic moment-rates for the eastern flank of Mt. Etna. The estimated moment-rates have been compared in terms of seismic efficiency. Results show that all the calculated efficiency values are lower than 40%, i.e., the geodetic moment-rate estimations are generally larger than the seismic and the geologic ones. Although a number of reasons may account for the observed discrepancy, we are confident that a large amount of the deformation affecting the eastern flank occurs aseismically

    Study of lithium encapsulation in porous membrane using ion and neutron beams

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    Ion track-etched membranes are porous systems obtained by etching of the latent ion tracks using a suitable etchant solution. In this work, control of the pores' spatial profiles and dimensions in PET polymers was achieved by varying etching temperature and etching time. For determination of the pores' shape, Ion Transmission Spectroscopy technique was employed. In this method, alterations of the energy loss spectra of the transmitted ions reflect alterations in the material density of the porous foils, as well as alterations of their thickness. Simulation code, developed by the team, allowed the tomographic study of the ion track 3D geometry and its evolution during chemical etching. From the doping of porous membranes with lithium-based solution and its analysis by Thermal Neutron Depth Profiling method, the ability of porous PET membranes to encapsulate nano-sized material was also inspected. The study is important for various applications, e.g., for catalysis, active agents, biosensors, etc

    Consensus on the use of the fixed combination calcipotriol/betamethasone dipropionate in the treatment of plaque psoriasis.

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    Calcipotriol, a vitamin D analogue, and betamethasone dipropionate, a high potency corticosteroid, are complementary agents for the topical treatment of psoriasis vulgaris. Robust evidence on the efficacy and safety of their fixed combination has been provided by randomized, double-blind, controlled clinical trials involving more than 7000 patients with the ointment formulation in psoriasis of the body and more than 4000 patients with the gel formulation in scalp psoriasis. These trials have shown that the fixed combination ointment is more effective and better tolerated, not only than placebo, but also than calcipotriol and tacalcitol monotherapies. In addition, it has proved, in most instances, to be more effective than betamethasone and at least as well tolerated. The same applies to the gel for scalp and body psoriasis. Safety studies have excluded that repeated courses of treatment with the fixed combination for up to one year produce systemic effects. Studies have also shown that the fixed combination treatment improves quality of life to a significantly greater extent than calcipotriol, with the once daily regimen most appreciated by patients, in both active disease and recurrency. Because of the extensive evidence, American and European guidelines recommend the calcipotriol/betamethasone dipropionate fixed combination a

    Deliveries by caesarean sections on request of women: legal-medical evidence

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    Introduction: In Italy the use of caesarean delivery has a rising trend moving away from European standards appeared on Euro-Peristat on maternal and child health, presenting the highest percentage of use of this procedure with significant regional differences. This study have analyzed the most recent data of a Sicilian reality about normal delivery and caesarean sections carried out in a hospital situated in Messina (Italy). Materials and methods: A total number of 1,573 medical records from 1st January 2011 to 31st December 2013 were analyzed and data gathered were statistically examined to describe general and specific parameters of the sample making use of Epi Info 7.1.4 software (CDC Atlanta – USA). Chi-square test was used to show any statistic differences among studied population. Results: Overall data showed that were carried out 38.27% of spontaneous deliveries, 7.06% of induced labor, and 54.67% of caesarean deliveries. There were no significant statistical differences between recourse to caesarean section and vaginal delivery in relation to nationality, age, level of education and/or work. The enrolled group, based on the parameters examined, was divided into appropriate caesarean section, in 79.49% of cases, inappropriate in 7.20% (mother’s request) and unjustified in 13.31% (with no indication, incomplete medical record). An examination of the anesthetic medical records showed that the caesarean section was considered to be urgent in 31.74% of the cases; however in 17.92% of these cases there is no information in the medical records justifying the use of emergency procedures. Conclusion: The reported data from the study that we conducted, lead to medical-legal and juridical considerations, especially as regards the use of caesarean delivery on the woman request. The complexity of the phenomenon requires the development of a variety of intervention strategies, not only for issues related to the reduction of health care costs, but also with regard to the clinical risk management and medical legal aspects related to the several profiles of professional responsibility

    Laser-generated nanoparticles to change physical properties of solids, liquids and gases

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    Synthesis of nanoparticles was possible employing a Nd: YAG pulsed laser at fundamental harmonic. The production of nanoparticles in water depends mainly on the laser parameters (pulse duration, energy, wavelength), the irradiation conditions (focal spot, repetition rate, irradiation time) and the medium where the ablation occurs (solid target, water, solution concentration). The nanoparticles can be introduced in solids, liquids or gases to change many physical characteristics. The optical properties of polymers and solutions, the wetting ability of liquids, the electron density of laser-generated plasma, represent some examples that can be controlled by the concentration of metallic nanoparticles (Au, Ag, Ti, Cu). Some bio-medical applications will be presented and discussed

    Production and characterization of micro-size pores for ion track etching applications

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    For many years the applications of ion track etch materials have increased considerably, like charged particles detection, molecular identification with nanopores, ion track filters, magnetic studies with nanowires and so on. Over the materials generally used as track detector, the Poly-Allyl-Diglycol Carbonate (PADC), offers many advantages, like its nearly 100 % detection efficiency for charged particle, a high resistance to harsh environment, the lowest detection threshold, a high abrasion resistance and a low production costs. All of these properties have made it particularly attractive material, even if due to its brittleness, obtaining a thin film (less than 500 ÎĽm) is still a challenge. In this work, PADC foils have been exposed to a-particles emitted by a thin radioactive source of 241Am and to C ions from the Tandetron 4130 MC accelerator. The latent tracks generated in the polymer have been developed using a standard etching procedure in 6.25 NaOH solution. The dependence of the ion tracks' geometry on the ion beam energy and fluence has been evaluated combining the information obtained through a semiautomatic computer script that selects the etched ion tracks according to their diameter and mean grey value and nanometric resolution images by atomic force microscopy

    Etn@ref: a geodetic reference frame for Mt. Etna GPS networks

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    In volcanology, one of the most important instruments for scientific community interested in modelling the physical processes related to magma movements in the shallow crust is geodetic data. Since the end of the 1980s, GPS surveys and Continuous GPS stations (CGPS) have greatly improved the possibility to measure such movements with high time and space resolution. However, physical modelling requires that any external influence on the data, not directly related to the investigated quantity, must be filtered. One major tricky factor in determining a deformation field using GPS displacement vectors and velocities is the correct choice of a stable reference frame. In this work, using more than a decade of GPS measurements, we defined a local reference frame in order to refer the Mt. Etna ground deformation pattern to a rigid block. In particular, we estimated the Euler pole for the rigid block by minimizing, with a weighted least squares inversion, the adjustments to two horizontal components of GPS velocity at 13 “fiducial” sites located within 350 km around Mt. Etna. The inversion inferred an Euler pole located at 38.450° N and -107.702° E and a rotation rate of 0.263 deg/Myr

    Instrumentation for study of nanomaterials in NPI REZ (New laboratory for material study in Nuclear Physics Institute in REZ)

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    Nano-sized materials become irreplaceable component of a number of devices for every aspect of human life. The development of new materials and deepening of the current knowledge require a set of specialized techniques-deposition methods for preparation/modification of the materials and analytical tools for proper understanding of their properties. A thoroughly equipped research centers become the requirement for the advance and development not only in nano-sized field. The Center of Accelerators and Nuclear Analytical Methods (CANAM) in the Nuclear Physics Institute (NPI) comprises a unique set of techniques for the synthesis or modification of nanostructured materials and systems, and their characterization using ion beam, neutron beam and microscopy imaging techniques. The methods are used for investigation of a broad range of nano-sized materials and structures based on metal oxides, nitrides, carbides, carbon-based materials (polymers, fullerenes, graphenes, etc.) and nano-laminate composites (MAX phases). These materials can be prepared at NPI using ion beam sputtering, physical vapor deposition and molecular beam epitaxy. Based on the deposition method and parameters, the samples can be tuned to possess specific properties, e.g., composition, thickness (nm-ÎĽm), surface roughness, optical and electrical properties, etc. Various nuclear analytical methods are applied for the sample characterization. RBS, RBS-channeling, PIXE, PIGE, micro-beam analyses and Transmission Spectroscopy are accomplished at the Tandetron 4130MC accelerator, and additionally the Neutron Depth Profiling (NDP) and Prompt Gamma Neutron Activation (PGNA) analyses are performed at an external neutron beam from the LVR-15 research reactor. The multimode AFM facility provides further surface related information, magnetic/electrical properties with nano-metric precision, nano-indentation, etc

    A comprehensive interpretative model of slow slip events on Mt. Etna’s eastern flank

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    Starting off from a review of previous literature on kinematic models of the unstable eastern flank of Mt. Etna, we propose a new model. The model is based on our analysis of a large quantity of multidisciplinary data deriving from an extensive and diverse network of INGV monitoring devices deployed along the slopes of the volcano. Our analysis had a twofold objective: first, investigating the origin of the recently observed slow-slip events on the eastern flank of Mt. Etna; and second, defining a general kinematic model for the instability of this area of the volcano. To this end, we investigated the 2008–2013 period using data collected from different geochemical, geodetic, and seismic networks, integrated with the tectonic and geologic features of the volcano and including the volcanic activity during the observation period. The complex correlations between the large quantities of multidisciplinary data have given us the opportunity to infer, as outlined in this work, that the fluids of volcanic origin and their interrelationship with aquifers, tectonic and morphological features play a dominant role in the large scale instability of the eastern flank of Mt. Etna. Furthermore, we suggest that changes in the strain distribution due to volcanic inflation/deflation cycles are closely connected to changes in shallow depth fluid circulation. Finally, we propose a general framework for both the short and long term modeling of the large flank displacements observed.Published635–6581IT. Reti di monitoraggio e OsservazioniJCR Journalrestricte
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