6 research outputs found
Failure Propagation Controlling for Frangible Composite Canister Design
The complexity in predicting the damage initiation and failure propagation controlling in composite structures is challenging. The focus of this paper is to design a potential component for new ship gunnels to make the composite canister affordable in structural applications by using a damage tolerant design approach. The design of a new tailgate configuration was investigated, taking into account the correct fragmentation of the structure to ensure a clear ejection while reducing the weight of the panels by exploiting the properties of the composite material. The complex geometry of the tailgate, the high impulse load, the energy transferred to the tailgate during missile impact, and how to safely break large panel flaps are elements that characterize the sizing of the composite component to meet the stringent ejection requirements in the life cycle of a missile during takeoff. The numerical simulations were performed using the LS/Dyna code and its explicit formulation was contemplated to take into account the geometrical, contact, and material non linearities
Wired threaded inserts in joints with steel screws and aluminium nuts: A parametric study on their effectiveness
The aim of this research was to investigate on bolted joints characterized by steel screws and aluminum nuts by means of numerical simulation. 2D and 3D CAD/FEM parametric models were developed in order to determine the preload distribution in joints with and without a Wired Threaded Inserts (WTI), so as to compare the trend of the stress distributions and the amount of load applied to each thread. The operating mechanisms and the effectiveness of a WTI were investigated in a parametric study by means of which the most important factors of the joint (materials, class, diameter, Engagement Ratio (ER), tolerance bands) were varied
Anticoagulation in acute ischemic stroke patients with mechanical heart valves : to bridge or not with heparin. The ESTREM study
Anticoagulation in acute ischemic stroke patients with mechanical heart valves: To bridge or not with heparin. The ESTREM study
Anticoagulation in acute ischemic stroke patients with mechanical heart valves: To bridge or not with heparin. The ESTREM study
Introduction: The best therapeutic strategy for patients with mechanical heart valves (MHVs) having acute ischemic stroke during treatment with vitamin K antagonists (VKAs) remain unclear. Being so, we compared the outcomes for: (i) full dose heparin along with VKA (bridging therapy group) and (ii) restarting VKA without heparin (nonbridging group). Patients and methods: For this multicenter observational cohort study, data on consecutive acute ischemic stroke patients with MHV was retrospectively collected from prospective registries. Propensity score matching (PSM) was adopted to adjust for any treatment allocation confounders. The primary outcome was the composite of stroke, systemic embolism, symptomatic cerebral bleeding, and major extracerebral bleeding at 90 days. Results: Overall, 255 out of 603 patients (41.3%) received bridging therapy: 36 (14.1%) had combined outcome, compared with 28 (8.0%) in the nonbridging group (adjusted OR 1.83; 95% CI 1.05-3.18; p = 0.03). Within the bridging group, 13 patients (5.1%) compared to 12 (3.4%) in the nonbridging group had an ischemic outcome (adjusted OR 1.71; 95% CI 0.84-3.47; p = 0.2); major bleedings were recorded in 23 (9.0%) in the bridging group and 16 (4.6%) in the nonbridging group (adjusted OR 1.88; 95% CI 0.95-3.73; p = 0.07). After PSM, 36 (14.2%) of the 254 bridging patients had combined outcome, compared with 23 (9.1%) of 254 patients in the nonbridging group (OR 1.66; 95% CI 0.95-2.85; p = 0.07). Conclusion: Acute ischemic stroke patients with MHV undergoing bridging therapy had a marginally higher risk of ischemic or hemorrhagic events, compared to nonbridging patients
sj-pdf-1-eso-10.1177_23969873231186863 – Supplemental material for Anticoagulation in acute ischemic stroke patients with mechanical heart valves: To bridge or not with heparin. The ESTREM study
Supplemental material, sj-pdf-1-eso-10.1177_23969873231186863 for Anticoagulation in acute ischemic stroke patients with mechanical heart valves: To bridge or not with heparin. The ESTREM study by Maurizio Paciaroni, Valeria Caso, Michele Romoli, Cecilia Becattini, Alexander Salerno, Costanza Rapillo, Fanny Simonnet, Davide Strambo, Isabella Canavero, Marialuisa Zedde, Rosario Pascarella, Sung-Il Sohn, Simona Sacco, Raffaele Ornello, Kristian Barlinn, Daniela Schoene, Jan Rahmig, Maria Giulia Mosconi, Ilaria Leone De Magistris, Andrea Alberti, Michele Venti, Giorgio Silvestrelli, Alfonso Ciccone, Marina Padroni, Michele Laudisi, Andrea Zini, Luana Gentile, Odysseas Kargiotis, Georgios Tsivgoulis, Rossana Tassi, Francesca Guideri, Maurizio Acampa, Luca Masotti, Elisa Grifoni, Alessandro Rocco, Marina Diomedi, Theodore Karapanayiotides, Stefan T Engelter, Alexandros A Polymeris, Annaelle Zietz, Fabio Bandini, Pietro Caliandro, Giuseppe Reale, Marco Moci, Aurelia Zauli, Manuel Cappellari, Andrea Emiliani, Antonio Gasparro, Valeria Terruso, Marina Mannino, Elisa Giorli, Danilo Toni, Marco Andrighetti, Anne Falcou, Lina Palaiodimou, George Ntaios, Dimitrios Sagris, Efstathia Karagkiozi, Anastasia Adamou, Panagiotis Halvatsiotis, Yuriy Flomin, Umberto Scoditti, Antonio Genovese, Nemanja Popovic, Leonardo Pantoni, Francesco Mele, Nicola Molitierno, Piergiorgio Lochner, Alessandro Pezzini, Massimo Del Sette, Davide Sassos, Sotirios Giannopoulos, Maria Kosmidou, Evangelos Ntais, Enrico Maria Lotti, Vincenzo Mastrangelo, Alberto Chiti, Andrea Naldi, Peter Vanacker, Mario Ferrante, Vera Volodina, Michelangelo Mancuso, Nicola Giannini, Marco Baldini, Kostantinos Vadikolias, Sofia Kitmeridou, Carlo Emanuele Saggese, Tiziana Tassinari, Valentina Saia and Patrik Michel in European Stroke Journal</p