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Aims The FLXibility Post-Approval Study collected data on unselected patients implanted with a WATCHMAN FLX in a commercial clinical setting. Methods and results Patients were implanted with a WATCHMAN FLX per local standard of care, with a subsequent first follow-up visit from 45 to 120 days post-implant and a final follow-up at 1-year post-procedure. A Clinical Event Committee adjudicated all major adverse events and TEE/CT imaging results were adjudicated by a core laboratory. Among 300 patients enrolled at 17 centres in Europe, the mean age was 74.6 ± 8.0 years, mean CHA2DS2-VASc score was 4.3 ± 1.6, and 62.1% were male. The device was successfully implanted in 99.0% (297/300) of patients. The post-implant medication regimen was DAPT for 87.3% (262/300). At first follow-up, core-lab adjudicated complete seal was 88.2% (149/169), 9.5% (16/169) had leak <3 mm, 2.4 (4/169) had leak ≥3 mm to ≤5 mm, and 0% had >5 mm leak. At 1 year, 93.3% (280/300) had final follow-up; 60.5% of patients were on a single antiplatelet medication, 21.4% were on DAPT, 5.6% were on direct oral anticoagulation, and 12.1% were not taking any antiplatelet/anticoagulation medication. Adverse event rates through 1 year were: all-cause death 10.8% (32/295); CV/unexplained death 5.1% (15/295); disabling and non-disabling stroke each 1.0% (3/295, all non-fatal); pericardial effusion requiring surgery or pericardiocentesis 1.0% (3/295); and device-related thrombus 2.4% (7/295). Conclusion The WATCHMAN FLX device had excellent procedural success rates, high LAA seal rates, and low rates of thromboembolic events in everyday clinical practice. [ABSTRACT FROM AUTHOR]

Objectives: The PROGRESS PVL registry evaluated transcatheter aortic valve implantation (TAVI) in patients treated with ACURATE neo, a supra-annular self-expanding bioprosthetic aortic valve.Background: While clinical outcomes with TAVI are comparable with those achieved with surgery, residual aortic regurgitation (AR) and paravalvular leak (PVL) are common complications. The ACURATE neo valve has a pericardial sealing skirt designed to minimize PVL.Methods: The primary endpoint was the rate of total AR over time, as assessed by a core echocardiographic laboratory. The study enrolled 500 patients (mean age: 81.8 ± 5.1 years; 61% female; mean baseline STS score: 6.0 ± 4.5%) from 22 centers in Europe and Canada; 498 patients were treated with ACURATE neo.Results: The rate of ≥ moderate AR was 4.6% at discharge and 3.1% at 12 months; the rate of ≥ moderate PVL was 4.6% at discharge and 2.6% at 12 months. Paired analyses showed significant improvement in overall PVL between discharge and 12 months (P < 0.001); 64.6% of patients had no change in PVL grade, 24.9% improved, and 10.5% worsened. Patients also exhibited significant improvement in transvalvular gradient (P < 0.001) and effective orifice area (P=0.01). The mortality rate was 2.2% at 30 days and 11.3% at 12 months. The permanent pacemaker implantation (PPI) rate was 10.2% at 30 days and 12.2% at 12 months.Conclusions: Results from PROGRESS PVL support the sustained safety and performance of TAVI with the ACURATE neo valve, showing excellent valve hemodynamics, good clinical outcomes, and significant interindividual improvement in PVL from discharge to 12-month follow-up. [ABSTRACT FROM AUTHOR]

This paper presents the modeling, design, fabrication and testing of monolithic electrostatic curved-electrode zipping actuators fabricated by deep reactive ion etching (DRIE). In contrast to traditional curved-electrode zipping actuators, the design of the actuators presented here utilizes a compliant starting cantilever to significantly reduce the initial pull-in voltage by closing the gap (kerf) generated by DRIE. Thus, the actuators achieve high actuation force at a relatively low voltage. For example, two actuators each with dimensions of 4.5 mm * 100 [micro]m * 300 [micro]m are used to drive a bistable MEMS relay. Together, the two actuators provide up to 10 mN of force over their 80 [micro]m stroke at 140 V. Measurements of the force-displacement relation of these actuators confirm theoretical expectations based both on numerical and analytical methods. Finite element analysis is employed to predict the behavior of the complete bistable relay system. Index Terms--Curved-electrode, deep-reactive ion-etched (DRIE), electrostatic, zipping actuator.

The characteristics of the electric double layer formed at a negatively charged metal electrode in contact with pure water are explored in this article. Based on the electric field distribution of the Modified Poisson Boltzmann (MPB) model, which contains the activity corrections only, the study evaluates the effects of finite ion size, polarization, image potential and field dissociation on the distribution of the hydronium ion concentration.

The effect of splitter plates (SP) on current interruption at medium voltage (MV) level is theoretically investigated in the framework of Mayr's arc model, which is generalized to take into account the electrode fall voltage, V0, of the SP. The model is analytically solved in the current zero (CZ) region where the current (before CZ) and the voltage (after CZ) can be linearized with respect to time. The current turns out to be successfully interrupted if the total electrode fall voltage, NV0, for N − 1 SP plus contact electrodes, is larger than twice the transient recovery voltage, ${\boldsymbol{U}} \approx {\dot{\boldsymbol{U}t}}$ , at the characteristic arc decay time, t = τ, after CZ: ${\boldsymbol{N}}{{\boldsymbol{V}}_0} > 2{\dot{\boldsymbol{U}\tau }}$. For ${\boldsymbol{N}}{{\boldsymbol{V}}_0} < 2{\dot{\boldsymbol{U}\tau }}$ , an additional thermal condition must be satisfied, where also the current rate, ${\dot{\boldsymbol{I}}} = {\boldsymbol{\ dI}}/{\boldsymbol{dt}}$ before CZ, and the arc cooling power, K, are involved. The intuitive results lead to a simple understanding of the electrical effect of SP on current interruption at MV and serve as an initial design rule for the number of SP in different gases. [ABSTRACT FROM AUTHOR]

Ionic wind devices or electrostatic fluid accelerators are becoming of increasing interest as tools for thermal management, in particular for semiconductor devices. In this work, we present a numerical model for predicting the performance of such devices; its main benefit is the ability to accurately predict the amount of charge injected from the corona electrode. Our multiphysics numerical model consists of a highly nonlinear, strongly coupled set of partial differential equations including the Navier-Stokes equations for fluid flow, Poisson's equation for electrostatic potential, charge continuity, and heat transfer equations. To solve this system we employ a staggered solution algorithm that generalizes Gummel's algorithm for charge transport in semiconductors. Predictions of our simulations are verified and validated by comparison with experimental measurements of integral physical quantities, which are shown to closely match. [ABSTRACT FROM AUTHOR]

This article presents an open source software able to convert, display, and process medical images. It differentiates itself from the existing software by its ability to design complex processing pipelines and to wisely execute them on a large databases. An MP3 pipeline can contain unlimited homemade or ready-made processes and can be carried out with a parallel execution system. As a viewer, MP3 allows display of up to four images together and to draw Regions Of Interest (ROI). Two applications showing the strengths of the software are presented as examples: a preclinical study involving Magnetic Resonance Imaging (MRI) data and a clinical one involving Computed Tomography (CT) images. MP3 is downloadable at https://github.com/nifm-gin/MP3. [ABSTRACT FROM AUTHOR]

A model for the axially blown cylindrical arc is derived to determine the dependence of the maximum interruptible current rate, (dI/dt)(sub L), on the pressure, on the parallel capacitance, and on the line impedance for an SF(sub 6) arc. It is found that the arc resistance, at current zero with current rate equal to (dI/dt)(sub L), is pressure independent.

This paper reports on a strongly physics-based minimal circuit model for polycrystalline cores, such as ferrites, including dimensional resonance (DR). The models and main properties of DR and hysteresis are recalled, a circuit model is described that incorporates the various phenomena, and it is mentioned how its parameters are extracted by broadband linear response and low-frequency nonlinear measurements. Finally, the simulations are validated with measurements for a specific example. The model turns out to predict accurately the magnetic behavior in the high-frequency nonlinear region. [ABSTRACT FROM AUTHOR]