6 research outputs found

    Role of substrate quality on the performance of semipolar (11 2 - 2) InGaN light-emitting diodes

    Get PDF
    We compare the optical properties and device performance of unpackaged InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) emitting at ∼430 nm grown simultaneously on a high-cost small-size bulk semipolar (11 2 - 2) GaN substrate (Bulk-GaN) and a low-cost large-size (11 2 - 2) GaN template created on patterned (10 1 - 2) r-plane sapphire substrate (PSS-GaN). The Bulk-GaN substrate has the threading dislocation density (TDD) of ∼ and basal-plane stacking fault (BSF) density of 0 cm-1, while the PSS-GaN substrate has the TDD of ∼2 × 108cm-2 and BSF density of ∼1 × 103cm-1. Despite an enhanced light extraction efficiency, the LED grown on PSS-GaN has two-times lower internal quantum efficiency than the LED grown on Bulk-GaN as determined by photoluminescence measurements. The LED grown on PSS-GaN substrate also has about two-times lower output power compared to the LED grown on Bulk-GaN substrate. This lower output power was attributed to the higher TDD and BSF density

    Pain Control in Breast Surgery: Survey of Current Practice and Recommendations for Optimizing Management—American Society of Breast Surgeons Opioid/Pain Control Workgroup

    Get PDF
    Introduction: The opioid epidemic in the United States is a public health crisis. Breast surgeons are obligated to provide good pain control for their patients after surgery but also must minimize administration of narcotics to prevent a surgical episode of care from becoming a patient's gateway into opioid dependence. Methods: A survey to ascertain pain management practice patterns after breast surgery was performed. A review of currently available literature that was specific to breast surgery was performed to create recommendations regarding pain management strategies. Results: A total of 609 surgeons completed the survey and demonstrated significant variations in pain management practices, specifically within regards to utilization of regional anesthesia (e.g., nerve blocks), and quantity of prescribed narcotics. There is excellent data to guide the use of local and regional anesthesia. There are, however, fewer studies to guide narcotic recommendations; thus, these recommendations were guided by prevailing practice patterns. Conclusions: Pain management practices after breast surgery have significant variation and represent an opportunity to improve patient safety and quality of care. Multimodality approaches in conjunction with standardized quantities of narcotics are recommended
    corecore