We introduce a new class of soft actuators based on the buckling of locally patterned elastic cylindrical shells that can be designed to reversibly achieve flexural or twisting motion. Depressurizing ...our samples allows for tunable and controllable motion. Given that the deformation is primarily governed by geometry and elasticity, the resulting modes of actuation should be readily scalable.
Background
Remote monitoring (RM) can remotely detect atrial tachyarrhythmias (ATAs). The benefit of RM compared to conventional follow‐up in the detection and management of ATA was assessed in ...recipients of dual‐chamber pacemakers.
Methods
The multicenter randomized SETAM study enrolled 595 patients in sinus rhythm with a CHA2DS2‐VASc score ≥2, without ATA history and untreated with antiarrhythmics and antithrombotics, randomly assigned to RM (RM‐ON; n = 291) versus ambulatory follow‐up (RM‐OFF; n = 304) during 12.8 ± 3.3 months. ATA occurrence, burden, and management were analyzed together with adverse clinical events.
Results
Patients were 79 ± 8 years old, 63% men, with a CHA2DS2‐VASc score of 3.7± 1.2. ATA were detected in 83 patients (28%) in the RM‐ON versus 66 (22%) in the RM‐OFF group (P = 0.06). The median time between the pacemaker implantation and the first treated ATA was 114 days 44; 241 in the RM‐ON versus 224 days 67; 366 in the RM‐OFF group (hazard ratio HR = 0.56; 95% confidence interval CI: 0.37–0.86; P = 0.01). Therapies for ATA were initiated in 92 patients and the time to treatment of ATA was shortened by 44% in the RM‐ON group (HR = 0.565; 95% CI: 0.37–0.86; P = 0.01). Over the last 4 months of follow‐up, the mean ATA burden was alleviated by 4 hours/day (18%) in the RM‐ON group. The rate of adverse clinical events was similar in both groups.
Conclusion
Remotely monitored patients were diagnosed and treated earlier for ATA, and subsequently had a lower ATA burden.
Study Objective: To describe the daily routine application of a new telemonitoring system in a large population of cardiac device recipients.
Methods: Data transmitted daily and automatically by a ...remote, wireless Home Monitoring™ system (HM) were analyzed. The average time gained in the detection of events using HM versus standard practice and the impact of HM on physician workload were examined. The mean interval between device interrogations was used to compare the rates of follow‐up visits versus that recommended in guidelines.
Results: 3,004,763 transmissions were made by 11,624 recipients of pacemakers (n = 4,631), defibrillators (ICD; n = 6,548), and combined ICD + cardiac resynchronization therapy (CRT‐D) systems (n = 445) worldwide. The duration of monitoring/patient ranged from 1 to 49 months, representing 10,057 years. The vast majority (86%) of events were disease‐related. The mean interval between last follow‐up and occurrence of events notified by HM was 26 days, representing a putative temporal gain of 154 and 64 days in patients usually followed at 6‐ and 3‐month intervals, respectively. The mean numbers of events per patient per month reported to the caregivers for the overall population was 0.6. On average, 47.6% of the patients were event‐free. The mean interval between follow‐up visits in patients with pacemakers, single‐chamber ICDs, dual chamber ICDs, and CRT‐D systems were 5.9 ± 2.1, 3.6 ± 3.3, 3.3 ± 3.5, and 1.9 ± 2.9 months, respectively.
Conclusions: This broad clinical application of a new monitoring system strongly supports its capability to improve the care of cardiac device recipients, enhance their safety, and optimize the allocation of health resources.
We numerically investigate the stability and linear oscillatory behavior of a naturally diverging mass whose potential energy is harmonically modulated. It is known that in the Kapitza limit, i.e. ...when the period of modulation is much smaller than the diverging time, the collapsing mass can be dynamically stabilized and behave like an effective classic harmonic oscillator. We find that in the regime where the period of modulation is larger than the collapsing time of the mass, dynamical stabilization is still possible but in a discrete fashion. Only almost-periodic vibrational modes, or Floquet forms (FFs), are allowed that are located in independent stability stripes in the modulation parameter space. Reducing the FFs to their periodic eigenfunctions, one can transform the original equation of motion to a dimensionless Schrödinger stationary wave equation with a harmonic potential. This transformation allows for an analytical prediction of the stability stripes and the modal shapes of the vibrating mass. These results shed new light on the stability of linear dynamical systems, analytical solutions of Mathieu equations and on the relations between Initial and Boundary Value Problems.
•Possible to stabilize, in theory, a Kapitza oscillator with slow forcing excitations.•In this case, stabilization is discrete in the modulation parameter space.•The stable vibrational modes have a compact support on each period.•Those modes can be analytically predicted by a stationary wave equation.
We numerically investigate the stability and linear oscillatory behavior of a naturally diverging mass whose potential energy is harmonically modulated. It is known that in the Kapitza limit, i.e. ...when the period of modulation is much smaller than the diverging time, the collapsing mass can be dynamically stabilized and behave like an effective classic harmonic oscillator. We find that in the regime where the period of modulation is larger than the collapsing time of the mass, dynamical stabilization is still possible but in a discrete fashion. Only almost-periodic vibrational modes, or Floquet forms (FFs), are allowed that are located in independent stability stripes in the modulation parameter space. Reducing the FFs to their periodic eigenfunctions, one can transform the original equation of motion to a dimensionless Schrödinger stationary wave equation with a harmonic potential. This transformation allows for an analytical prediction of the stability stripes and the modal shapes of the vibrating mass. These results shed new light on the stability of linear dynamical systems, analytical solutions of Mathieu equations and on the relations between Initial and Boundary Value Problems.
Highlights • The prevalence of atrial flutter in patients with DM1 is 8.5%. • Atrial flutter may be associated with ischemic stroke even in low risk DM1 patients. • Severe bradycardia may be ...triggered by antiarrhythmics used for the treatment of atrial flutter. • Radiofrequency ablation can prevent atrial flutter recurrences in patients with DM1.
We present a spectral method to compute the transverse vibrational modes, or Floquet Forms (FFs), of a 2
D
bi-articulated bar in periodic elastic state due to an end harmonic compressive force. By ...changing the directional nature of the applied load, the trivial straight Ziegler column exhibits the classic instabilities of stationary states of dynamical system. We use this simple structure as a numerical benchmark to compare the various spectral methods that consist in computing the FFs from the spectrum of a truncated Hill matrix. We show the necessity of sorting this spectrum and the benefit of computing the fundamental FFs that converge faster. Those FFs are almost periodic entities that generalize the concept of harmonic modal analysis of structures in equilibria to structures in periodic states. Like their particular harmonic relatives, FFs allow to get physical insights in the bifurcations of periodic stationary states. Notably, the local loss of stability is due to the frequency lock-in of the FFs for certain modulation parameters. The presented results could apply to many structural problems in mechanics, from the vibrations of rotating machineries with shape imperfections to the stability of periodic limit cycles or of any slender structures with tensile or compressive periodic elastic stresses.
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