288 research outputs found

    Safety analysis in large volume vacuum systems like tokamak: Experiments and numerical simulation to analyze vacuum ruptures consequences

    Get PDF
    The large volume vacuum systems are used in many industrial operations and research laboratories. Accidents in these systems should have a relevant economical and safety impact. A loss of vacuum accident (LOVA) due to a failure of the main vacuum vessel can result in a fast pressurization of the vessel and consequent mobilization dispersion of hazardous internal material through the braches. It is clear that the influence of flow fields, consequence of accidents like LOVA, on dust resuspension is a key safety issue. In order to develop this analysis an experimental facility is been developed: STARDUST. This last facility has been used to improve the knowledge about LOVA to replicate a condition more similar to appropriate operative condition like to kamaks. By the experimental data the boundary conditions have been extrapolated to give the proper input for the 2D thermofluid-dynamics numerical simulations, developed by the commercial CFD numerical code. The benchmark of numerical simulation results with the experimental ones has been used to validate and tune the 2D thermofluid-dynamics numerical model that has been developed by the authors to replicate the LOVA conditions inside STARDUST. In present work, the facility, materials, numerical model, and relevant results will be presented. © 2014 A. Malizia et al

    Folgoration as an Example of Pathergy in a Patient Affected by Pyoderma Gangrenosum and Takayasu's Arteritis

    Get PDF
    Pyoderma gangrenosum (PG) is a neutrophilic dermatosis of unknown aetiology. Clinical manifestations of PG are characterized by destructive, necrotizing, and noninfective ulceration of the skin. 20–30% of cases are initiated and aggravated by minor trauma or surgery, a phenomenon named pathergy. PG is related to several autoimmune diseases including ulcerative colitis, Crohn's disease, rheumatoid arthritis, and monoclonal gammopathy. The association with Takayasu's arteritis (TA), a chronic inflammatory and stenotic disease of large and medium-sized arteries, is instead less common. We report a case of PG associated with TA that was induced by an accident with folgoration of the skin; in this case the folgoration can be considered as an exemple of Pathergy, that is, a characteristic feature of PG

    Use of biological drugs in patients with psoriasis and psoriatic arthritis in italy: Results from the PSONG survey

    Get PDF
    This Italian multicenter retrospective study compared the drug survival and efficacy of differentanti-TNF agents in psoriasis (PsO) and psoriatic arthritis (PsA) patients. A database of PsO/PsApatients treated with adalimumab, etanercept, and infliximab from May 2013 to May 2014 wasanalyzed. PASI 75, 90, and 100 was calculated at each time point to evaluate efficacy. Drug sur-vival rate and probability of maintaining PASI response were evaluated. The impact of dependentvariables on probability of PASI 75 loss was evaluated by logistic regression. 1,235 patients wereincluded, 577 with PsO and 658 with PsA. Highest survival rates were observed with adalimumabfollowed by etanercept and infliximab in PsO and PsA patients. The probability of maintainingPASI response was significantly higher for adalimumab followed by infliximab. For PsO patients,the odds of losing PASI 75 was higher in etanercept-treated patients (OR: 8.1; 95% CI: 4.2–15.6,p<.001) or infliximab (OR: 6.6; 95% CI: 2.6–16.3,p<.001) vs. adalimumab. Likewise, for PsApatients the odds of losing PASI 75 was higher in etanercept-treated patients (OR: 2.3; 95% CI:1.4–3.8,p5.01) or infliximab (OR: 2.2; 95% CI: 1.1–4.1,p5.018) vs. adalimumab. Adalimumabcould be the best therapeutic option over other anti-TNF agents for the treatment of PsO and PsApatients

    Primary cutaneous alk positive anaplastic large cell lymphoma in a melanoma patient

    Get PDF
    Primary cutaneous anaplastic large cell lymphoma (PCALCL) is a raresubset of CD30+ lymphoproliferative disorder, characterized by the presenceof large anaplastic cells, which express CD30, CD2, CD3, CD4, and CD5. A 62 year-old male patient presented to our Institute with a history of a fastgrowing and pinkish-brown asymptomatic cutaneous nodule. His medical past history was positive for a malignant melanoma (MM) of the abdomen (0.7 mm Breslow thickness; pT1a). Histologically the lesion showed a diffuse infiltrate consisting in cohesive sheets of large cells with anaplastic morphology with a kidney-shaped nucleus, also known as hallmark cells. Immunohistochemical studies revealed a CD30 expression, and a positivity to perforin and anaplastic lymphoma kinase (ALK). The laboratory and instrumental investigations were all normal and a final diagnosis of PCALCL was made. The patient showed a good response to radiotherapy. Usually PCALCL shares with systemic anaplastic large cell lymphoma (ALCL) the presence of neoplastic CD30+ large T cells, but lack ALK translocations and protein expression. However, the detection of ALK expression in PCALCL should be considered highly suspicious of a cutaneous manifestation of an underlying systemic disease (not detected in our patient). We recommend to exclude a systemic involvement in this kind of disease, with a strict follow-up, especially in patients with double malignancies

    Detection of pollutant sources in the atmosphere with Lidar/Dial techniques: Results of an experimental campaign in the south of Italy

    Get PDF
    In the last years, surveying large regions of the atmosphere in an automatic way, for early detection of pollutant sources in urban and industrial areas, has become a strategic objective of various public health organizations. The Lidar/Dial technique has become a well-established laser remote sensing method for atmosphere monitoring. It is often used to probe almost any level of the atmosphere and to acquire information necessary to validate theoretical models about different topics of atmospheric physics. It can also be deployed for environment surveying by monitoring particles, aerosols and molecules. For these reasons, an experimental campaign for evaluating the performances of a Lidar/Dial system in detecting pollutants (particulate and/or chemical compounds) has been carried out in an industrial area in the south of Italy. In this work, a homemade Lidar/Dial system (developed and built by the authors) and the results of the experimental campaign will be presented and discussed. © 2014 AEIT

    Study of shock waves generation, hot electron production and role of parametric instabilities in an intensity regime relevant for the shock ignition

    Get PDF
    We present experimental results at intensities relevant to Shock Ignition obtained at the sub-ns Prague Asterix Laser System in 2012 . We studied shock waves produced by laser-matter interaction in presence of a pre-plasma. We used a first beam at 1ω (1315 nm) at 7 × 10 13 W/cm 2 to create a pre-plasma on the front side of the target and a second at 3ω (438 nm) at ∌ 10 16 W/cm 2 to create the shock wave. Multilayer targets composed of 25 (or 40 ÎŒm) of plastic (doped with Cl), 5 ÎŒm of Cu (for Kα diagnostics) and 20 ÎŒm of Al for shock measurement were used. We used X-ray spectroscopy of Cl to evaluate the plasma temperature, Kα imaging and spectroscopy to evaluate spatial and spectral properties of the fast electrons and a streak camera for shock breakout measurements. Parametric instabilities (Stimulated Raman Scattering, Stimulated Brillouin Scattering and Two Plasmon Decay) were studied by collecting the back scattered light and analysing its spectrum. Back scattered energy was measured with calorimeters. To evaluate the maximum pressure reached in our experiment we performed hydro simulations with CHIC and DUED codes. The maximum shock pressure generated in our experiment at the front side of the target during laser-interaction is 90 Mbar. The conversion efficiency into hot electrons was estimated to be of the order of ∌ 0.1% and their mean energy in the order ∌50 keV. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distributio
    • 

    corecore