341 research outputs found
Smart monitoring system based on adaptive current control for superconducting cable test
A smart monitoring system for superconducting cable test is proposed with an adaptive currentcontrol of asuperconductingtransformer secondary. The design, based on Fuzzy Gain Scheduling, allows thecontrollerparameters to adapt continuously, and finely, to the working variations arising fromtransformer nonlineardynamics. The control system is integrated in a fully digital control loop, with all therelated benefits, i.e., high noise rejection, ease of implementation/modification, and soon. In particular, an accurate model of the system,controlled by aFuzzy Gain Scheduler of the superconducting transformer, was achieved by an experimental campaignthrough the working domain at several current ramp rates. The model performance wascharacterized by simulation, under all the main operating conditions, in order to guidethe controllerdesign. Finally, the proposed monitoring system was experimentally validated at EuropeanOrganization for Nuclear Research (CERN) in comparison to the state-of-the-artcontrol system[P. Arpaia, L. Bottura, G. Montenero, and S. LeNaour, âPerformance improvement of a measurement station forsuperconductingcable test,â Rev. Sci. Instrum.83, 095111 (2012)] of theFacility for the Research on Superconducting Cables, achieving a significant performanceimprovement: a reduction in the system overshoot by 50%, with a related attenuationof the corresponding dynamic residual error (both absolute and RMS) up to 52%
Acute success and short-term follow-up of catheter ablation of isthmus-dependent atrial flutter; a comparison of 8 mm tip radiofrequency and cryothermy catheters
Objectives: To compare the acute success and short-term follow-up of ablation of atrial flutter using 8 mm tip radiofrequency (RF) and cryocatheters. Methods: Sixty-two patients with atrial flutter were randomized to RF or cryocatheter (cryo) ablation. Right atrial angiography was performed to assess the isthmus. End point was bidirectional isthmus block on multiple criteria. A pain score was used and the analgesics were recorded. Patients were followed for at least 3 months. Results: The acute success rate for RF was 83% vs 69% for cryo (NS). Procedure times were similar (mean 144±48 min for RF, vs 158±49 min for cryo). More applications were given with RF than with cryo (26±17 vs. 18±10, p<0.05). Fluoroscopy time was longer with RF (29±15 vs. 19±12 min, p<0.02). Peak CK, CK-MB and CK-MB mass were higher, also after 24 h in the cryo group. Troponin T did not differ. Repeated transient block during application (usually with cryoablation) seemed to predict failure. Cryothermy required significantly less analgesia (p<0.01), and no use of long sheaths (p<0.005). The isthmus tended to be longer in the failed procedures (p=0.117). This was similar for both groups, as was the distribution of anatomic variations. Recurrences and complaints in the successful patients were similar for both groups, with a very low recurrence of atrial flutter after initial success. Concl
Chemical Composition, Minerals, Physicochemical Properties and Antioxidant Activity in Camu Camu Seed Oil.
Made available in DSpace on 2018-06-29T01:38:01Z (GMT). No. of bitstreams: 1
055.pdf: 668460 bytes, checksum: 67f5bc3d0a53d34e34d4f1c4d380de8e (MD5)
Previous issue date: 2018-06-28bitstream/item/179146/1/055.pd
Long term outcome of cavotricuspid isthmus cryoablation for the treatment of common atrial flutter in 180 patients: A single center experience
Association between atrial fibrillation and <i>Helicobacter pylori</i>
The connection between atrial fibrillation (AF) and H. pylori (HP) infection is still matter of debate. We performed a systematic review and metanalysis of studies reporting the association between AF and HF. A systematic review of all available reports in literature of the incidence of HP infection in AF and comparing this incidence with subjects without AF were analysed. Risk ratio and 95% confidence interval (CI) and risk difference with standard error (SE) were the main statistics indexes. Six retrospective studies including a total of 2921 were included at the end of the selection process. Nine hundred-fifty-six patients (32.7%) were in AF, whereas 1965 (67.3%) were in normal sinus rhythm (NSR). Overall, 335 of 956 patients with AF were HP positive (35%), whereas 621 were HP negative (65%). In addition, 643 of 1965 NSR patients (32.7%) were HP positive while 1,322 were negative (67.3%; Chi-square 2.15, pâ=â0.21). The Cumulative Risk Ratio for AF patients for developing an HP infection was 1.19 (95% CI 1.08â1.41). In addition, a small difference risk towards AF was found (0.11 [SEâ=â0.04]). Moreover, neither RR nor risk difference were influenced by the geographic area at meta-regression analysis. Finally, there was a weak correlation between AF and HP (coefficientâ=â0.04 [95% CI â0.01â0.08]). We failed to find any significant correlation between H. pylori infection and AF and, based on our data, it seems unlikely than HP can be considered a risk factor for AF. Further larger research is warranted
Effectiveness of cardiac resynchronization therapy in heart failure patients with valvular heart disease: comparison with patients affected by ischaemic heart disease or dilated cardiomyopathy. The InSync/InSync ICD Italian Registry
AimsTo analyse the effectiveness of cardiac resynchronization therapy (CRT) in patients with valvular heart disease (a subset not specifically investigated in randomized controlled trials) in comparison with ischaemic heart disease or dilated cardiomyopathy patients.Methods and resultsPatients enrolled in a national registry were evaluated during a median follow-up of 16 months after CRT implant. Patients with valvular heart disease treated with CRT (n = 108) in comparison with ischaemic heart disease (n = 737) and dilated cardiomyopathy (n = 635) patients presented: (i) a higher prevalence of chronic atrial fibrillation, with atrioventricular node ablation performed in around half of the cases; (ii) a similar clinical and echocardiographic profile at baseline; (iii) a similar improvement of LVEF and a similar reduction in ventricular volumes at 6-12 months; (iv) a favourable clinical response at 12 months with an improvement of the clinical composite score similar to that occurring in patients with dilated cardiomyopathy and more pronounced than that observed in patients with ischaemic heart disease; (v) a long-term outcome, in term of freedom from death or heart transplantation, similar to patients affected by ischaemic heart disease and basically more severe than that of patients affected by dilated cardiomyopathy.ConclusionIn 'real world' clinical practice, CRT appears to be effective also in patients with valvular heart disease. However, in this group of patients the outcome after CRT does not precisely overlap any of the two other groups of patients, for which much more data are currently available
Typical atrial flutter can effectively be treated using single one-minute cryoapplications: Results from a repeat electrophysiological study
HE-LHC: The High-Energy Large Hadron Collider â Future Circular Collider Conceptual Design Report Volume 4
In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre-of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries
- âŠ