Antireflection coatings from analogy between electron scattering and spin precession

We use the analogy between scattering of a wave from a potential, and the precession of a spin-half particle in a magnetic field, to gain insight into the design of an antireflection coating for electrons in a semiconductor superlattice. It is shown that the classic recipes derived for optics are generally not applicable due to the different dispersion law for electrons. Using the stability conditions we show that a Poisson distribution of impedance steps is a better approximation than is a Gaussian distribution. Examples are given of filters with average transmissivity exceeding 95% over an allowed band

A Multicenter Global Registry of Paclitaxel Drug-Coated Balloon in Dysfunctional Arteriovenous Fistulae and Grafts: 6-Month Results

Purpose: To assess the safety and clinical benefit of the Lutonix drug-coated balloon (DCB) catheter for the treatment of dysfunctional arteriovenous fistulae (AVF) and grafts (AVG) in a heterogenous real-world population. Materials and Methods: This multicenter, prospective study enrolled 320 subjects from 12 countries in 25 sites across Europe and Asia. A total of 392 lesions were treated with the Lutonix 035 DCB catheter. Lesions were de novo and restenotic, located in every part of the circuit from the cannulation zone to central venous outflow. In-stent restenotic lesions also were treated. The primary safety endpoint was freedom from serious adverse events involving the access circuit through 30 days. The primary effectiveness endpoint was target lesion primary patency (TLPP) through 6 months. Secondary endpoints included access circuit primary patency (ACPP) at 6 months and the investigation of factors that would independently influence the primary endpoints. Results: The primary safety endpoint was 95.5%, while TLPP was 73.9% at 6 months, per Kaplan-Meier survival analysis. ACPP was 71% at 6 months. TLPP for stenosis of AVFs was 78.1%. Subgroup analysis showed significantly improved TLPP when DCB was dilated for 65120 seconds (P = .007). TLPP was significantly better when predilation occurred compared with cases where only DCB angioplasty was performed (77% vs 48.6%, P = .0005). Conclusions: The Lutonix AV Global Registry confirms that the Lutonix DCB is a safe and effective treatment option in real-world patients with dysfunctional AVF or AVG. Procedural details had a significant role in TLPP. No significant difference in TLPP was observed among different treatment areas