202 research outputs found

    Effect of retrofit interventions on seismic fragility of Italian residential masonry buildings

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    In this paper, the vulnerability of ordinary unreinforced masonry (URM) buildings is analyzed, and the literature related to possible seismic retrofit interventions is reviewed in order to investigate their feasibility and effectiveness. These interventions are then simulated on a data-base of 445 buildings through Vulnus_4.0 software, that performs simplified mechanical analyses accounting for both global and local behavior of masonry buildings. The fragility of each building is assessed both in its as-built state and after the simulation of retrofit interventions. Fragility curves are then processed, and a fragility model for four building typologies is obtained for the as -built and the seismic retrofitted configurations. Lastly, mean damage maps are elaborated, and the performance of the proposed retrofit interventions is analyzed. The results of this work allow evaluating and comparing the improvement of seismic behavior brought by various retrofit in-terventions and could serve as a basis for further theoretical studies and for practical design in real cases

    Mechanics-based fragility curves for Italian residential URM buildings

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    Seismic risk assessment at the territorial level is now widely recognised as essential for countries with intense seismic activity, such as Italy. Academia is called to give its contribution in order to synergically deepen the knowledge about the various components of this risk, starting from the complex evaluation of vulnerability of the built heritage. In line with this, a mechanics-based seismic fragility model for Italian residential masonry buildings was developed and presented in this paper. This model is based on the classification of the building stock in macro-typologies, defined by age of construction and number of storeys, which being information available at national level, allow simulating damage scenarios and carrying out risk analyses on a territorial scale. The model is developed on the fragility of over 500 buildings, sampled according to national representativeness criteria and analysed through the Vulnus_4.0 software. The calculated fragility functions were extended on the basis of a reference model available in the literature, which provides generic fragilities for the EMS98 vulnerability classes, thus obtaining a fragility model defined on the five EMS98 damage states. Lastly, to assess the reliability of the proposed model, this was used to simulate damage scenarios due to the 2009 L’Aquila earthquake. Overall, the comparison between model results and observed damage showed a good fit, proving the model effectiveness

    Daedalus: A hardware signal analyser for Icarus

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    Icarus detector [1] is a large-volume (400 cm) liquid Argon TPC that requires continuous high rate sampling signal recording on each channel (about 50 000) to produce event images quite similar to the ones from bubble chambers. In order to optimize the memory usage, a signal feature extractor, that commands memory writing only upon signal detection, has been designed in VLSI CMOS. ( 1998 Elsevier Science B.V. All rights reserved

    Role of neuronal and inducible nitric oxide synthases in the guinea pig ileum myenteric plexus during in vitro ischemia and reperfusion

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    Background Intestinal ischemia and reperfusion (I/R) injury leads to abnormalities in motility, namely delay of transit, caused by damage to myenteric neurons. Alterations of the nitrergic transmission may occur in these conditions. This study investigated whether an in vitro I/R injury may affect nitric oxide (NO) production from the myenteric plexus of the guinea pig ileum and which NO synthase (NOS) isoform is involved. Methods The distribution of the neuronal (n) and inducible (i) NOS was determined by immunohistochemistry during 60 min of glucose/oxygen deprivation (in vitro ischemia) followed by 60 min of reperfusion. The protein and mRNA levels of nNOS and iNOS were investigated by Westernimmunoblotting and real time RT-PCR, respectively. NO levels were quantified as nitrite/nitrate. Key Results After in vitro I/R the proportion of nNOSexpressing neurons and protein levels remained unchanged. nNOS mRNA levels increased 60 min after inducing ischemia and in the following 5 min of reperfusion. iNOS-immunoreactive neurons, protein and mRNA levels were up-regulated during the whole I/R period. A significant increase of nitrite/nitrate levels was observed in the first 5 min after inducing I/R and was significantly reduced by Nx-propyl-L-arginine and 1400 W, selective inhibitors of nNOS and iNOS, respectively. Conclusions & Inferences Our data demonstrate that both iNOS and nNOS represent sources for NO overproduction in ileal myenteric plexus during I/R, although iNOS undergoes more consistent changes suggesting a more relevant role for this isoform in the alterations occurring in myenteric neurons following I/R

    Measurement of the muon decay spectrum with the ICARUS liquid Argon TPC

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    Examples are given which prove the ICARUS detector quality through relevant physics measurements. We study the muon decay energy spectrum from a sample of stopping muon events acquired during the test run of the ICARUS T600 detector. This detector allows the spatial reconstruction of the events with fine granularity, hence, the precise measurement of the range and dE/dx of the muon with high sampling rate. This information is used to compute the calibration factors needed for the full calorimetric reconstruction of the events. The Michel rho parameter is then measured by comparison of the experimental and Monte Carlo simulated muon decay spectra, obtaining rho = 0.72 +/- 0.06(stat.) +/- 0.08(syst.). The energy resolution for electrons below ~50 MeV is finally extracted from the simulated sample, obtaining (Emeas-Emc)/Emc = 11%/sqrt(E[MeV]) + 2%.Comment: 16 pages, 8 figures, LaTex, A4. Some text and 1 figure added. Final version as accepted for publication in The European Physical Journal

    The ICARUS Experiment, A Second-Generation Proton Decay Experiment and Neutrino Observatory at the Gran Sasso Laboratory

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    The final phase of the ICARUS physics program requires a sensitive mass of liquid Argon of 5000 tons or more. The T600 detector stands today as the first living proof that such large detector can be built and that liquid Argon imaging technology can be implemented on such large scales. After the successful completion of a series of technical tests to be performed at the assembly hall in Pavia, the T600 detector will be ready to be transported into the LNGS tunnel. The operation of the T600 at the LNGS will allow us (1) to develop the local infrastructure needed to operate our large detector (2) to start the handling of the underground liquid argon technology (3) to study the local background (4) to start the data taking with an initial liquid argon mass that will reach in a 5-6 year program the multi-kton goal. The T600 is to be considered as the first milestone on the road towards a total sensitive mass of 5000 tons: it is the first piece of the detector to be complemented by further modules of appropriate size and dimensions, in order to reach in a most efficient and rapid way the final design mass. In this document, we describe the physics program that will be accomplished within the first phase of the program

    Multi-centre phase II clinical trial of yttrium-90 resin microspheres alone in unresectable, chemotherapy refractory colorectal liver metastases

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    Background:This multi-centre phase II clinical trial is the first prospective evaluation of radioembolisation of patients with colorectal liver metastases (mCRC) who failed previous oxaliplatin-and irinotecan-based systemic chemotherapy regimens.Methods:Eligible patients had adequate hepatic, haemopoietic and renal function, and an absence of major hepatic vascular anomalies and hepato-pulmonary shunting. Gastroduodenal and right gastric arteries were embolised before hepatic arterial administration of yttrium-90 resin microspheres (median activity, 1.7 GBq; range, 0.9-2.2).Results:Of 50 eligible patients, 38 (76%) had received 654 lines of chemotherapy. Most presented with synchronous disease (72%), <4 hepatic metastases (58%), 25-50% replacement of total liver volume (60%) and bilateral spread (70%). Early and intermediate (<48 h) WHO G1-2 adverse events (mostly fever and pain) were observed in 16 and 22% of patients respectively. Two died due to renal failure at 40 days or liver failure at 60 days respectively. By intention-to-treat analysis using Response Evaluation Criteria in Solid Tumours, 1 patient (2%) had a complete response, 11 (22%) partial response, 12 (24%) stable disease, 22 (44%) progressive disease; 4 (8%) were non-evaluable. Median overall survival was 12.6 months (95% CI, 7.0-18.3); 2-year survival was 19.6%.Conclusion: Radioembolisation produced meaningful response and disease stabilisation in patients with advanced, unresectable and chemorefractory mCRC. \ua9 2010 Cancer Research UK All rights reserved

    Observation of long ionizing tracks with the ICARUS T600 first half-module

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    F. Arneodo, B. Bade"ek, A. Badertscher, B. Baiboussinov, M. Baldo Ceolin, G. Battistoni, B. Bekman, P. Benetti, E. Bernardini, M. Bischofberger, A. Borio di Tigliole, R. Brunetti, A. Bueno, E. Calligarich, M. Campanelli, C. Carpanese, D. Cavalli, F. Cavanna, P. Cennini, S. Centro, A. Cesana, C. Chen, D. Chen, D.B. Chen, Y. Chen, D. Cline, Z. Dai, C. De Vecchi, A. Dabrowska, R. Dolfini*, M. Felcini, A. Ferrari, F. Ferri, Y. Ge, A. Gigli Berzolari, I. Gil-Botella, K. Graczyk, L. Grandi, K. He, J. Holeczek, X. Huang, C. Juszczak, D. Kie"czewska, J. Kisiel, T. Koz"owski, H. Kuna-Ciska", M. Laffranchi, J. Łagoda, Z. Li, F. Lu, J. Ma, M. Markiewicz, A. Martinez de la Ossa, C. Matthey, F. Mauri, D. Mazza, G. Meng, M. Messina, C. Montanari, S. Muraro, S. Navas-Concha, M. Nicoletto, G. Nurzia, S. Otwinowski, Q. Ouyang, O. Palamara, D. Pascoli, L. Periale, G. Piano Mortari, A. Piazzoli, P. Picchi, F. Pietropaolo, W. P ! o"ch"opek, T. Rancati, A. Rappoldi, G.L. Raselli, J. Rico, E. Rondio, M. Rossella, A. Rubbia, C. Rubbia, P. Sala, D. Scannicchio, E. Segreto, F. Sergiampietri, J. Sobczyk, J. Stepaniak, M. Szeptycka, M. Szleper, M. Szarska, M. Terrani, S. Ventura, C. Vignoli, H. Wang, M. W ! ojcik, J. Woo, G. Xu, Z. Xu, A. Zalewska, J. Zalipska, C. Zhang, Q. Zhang, S. Zhen, W. Zipper a INFN Laboratori Nazionali del Gran Sasso, s.s. 17bis Km 18+910, Assergi (L'Aquila), Italy b Institute of Experimental Physics, Warsaw University, Warszawa, Poland c Institute for Particle Physics, ETH H . onggerberg, Z . urich, Switzerland Dipartimento di Fisica e INFN, Universit " a di Padova, via Marzolo 8, Padova, Italy Dipartimento di Fisica e INFN, Universit " a di Milano, via Celoria 16, Milano, Italy f Institute of Physics, University of Silesia, Katowice, Poland Dipartimento di Fisica e INFN, Universit " a di Pavia, via Bassi 6, Pavia, Italy Dpto de F!isica Te ! orica y del Cosmos & C.A.F.P.E., Universidad de Granada, Avda. Severo Ochoa s/n, Granada, Spain Dipartimento di Fisica e INFN, Universit " a dell'Aquila, via Vetoio, L'Aquila, Italy CERN, CH-1211 Geneva 23, Switzerland Politecnico di Milano (CESNEF), Universit " a di Milano, via Ponzio 34/3, Milano, Ital

    Overview of the TCV tokamak experimental programme

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    The tokamak a configuration variable (TCV) continues to leverage its unique shaping capabilities, flexible heating systems and modern control system to address critical issues in preparation for ITER and a fusion power plant. For the 2019-20 campaign its configurational flexibility has been enhanced with the installation of removable divertor gas baffles, its diagnostic capabilities with an extensive set of upgrades and its heating systems with new dual frequency gyrotrons. The gas baffles reduce coupling between the divertor and the main chamber and allow for detailed investigations on the role of fuelling in general and, together with upgraded boundary diagnostics, test divertor and edge models in particular. The increased heating capabilities broaden the operational regime to include T (e)/T (i) similar to 1 and have stimulated refocussing studies from L-mode to H-mode across a range of research topics. ITER baseline parameters were reached in type-I ELMy H-modes and alternative regimes with \u27small\u27 (or no) ELMs explored. Most prominently, negative triangularity was investigated in detail and confirmed as an attractive scenario with H-mode level core confinement but an L-mode edge. Emphasis was also placed on control, where an increased number of observers, actuators and control solutions became available and are now integrated into a generic control framework as will be needed in future devices. The quantity and quality of results of the 2019-20 TCV campaign are a testament to its successful integration within the European research effort alongside a vibrant domestic programme and international collaborations

    Langmuir probe electronics upgrade on the tokamak a configuration variable

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    A detailed description of the Langmuir probe electronics upgrade for TCV (Tokamak a Configuration Variable) is presented. The number of amplifiers and corresponding electronics has been increased from 48 to 120 in order to simultaneously connect all of the 114 Langmuir probes currently mounted in the TCV divertor and main-wall tiles. Another set of 108 amplifiers is ready to be installed in order to connect 80 new probes, built in the frame of the TCV divertor upgrade. Technical details of the amplifier circuitry are discussed as well as improvements over the first generation of amplifiers developed at SPC (formerly CRPP) in 1993/1994 and over the second generation developed in 2012/2013. While the new amplifiers have been operated successfully for over a year, it was found that their silicon power transistors can be damaged during some off-normal plasma events. Possible solutions are discussed. (C) 2019 Author(s)
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