We introduce ITO on graphene as a current-spreading layer for separated InGaN/GaN nanorod LEDs for the purpose of passivation-free and high light-extraction efficiency. Transferred graphene on InGaN/GaN nanorods effectively blocks the diffusion of ITO atoms to nanorods, facilitating the production of transparent ITO/graphene contact on parallel-nanorod LEDs, without filling the air gaps, like a bridge structure. The ITO/graphene layer sufficiently spreads current in a lateral direction, resulting in uniform and reliable light emission observed from the whole area of the top surface.
View Article and Find Full Text PDFAg nanoparticles are embedded in intentionally etched micro-circle p-GaN holes by means of a thermal agglomeration process to enhance the light absorption efficiency in InGaN/GaN multi-quantum-well (MQW) solar cells. The Ag nanoparticles are theoretically and experimentally verified to generate the plasmon light scattering and the localized field enhancement near the MQW absorption layer. The external quantum efficiency enhancement at a target wavelength region is demonstrated by matching the plasmon resonance of Ag nanoparticles, resulting in a J improvement of 9.
View Article and Find Full Text PDFKorean J Thorac Cardiovasc Surg
August 2015
Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder that is characterized by aggressive arterial and aortic disease, often involving the formation of aortic aneurysms. We describe the cases of two children with LDS who were diagnosed with aortic root aneurysms and successfully treated by valve-sparing aortic root replacement (VSRR) with a Valsalva graft. VSRR is a safe and suitable operation for children that avoids prosthetic valve replacement.
View Article and Find Full Text PDFKorean J Thorac Cardiovasc Surg
June 2015
Background: Extracorporeal membrane oxygenation (ECMO) has recently attracted interest as a treatment for severe acute respiratory distress syndrome (ARDS). However, the outcomes of this procedure in post-surgical settings have not yet been characterized. In this study, we evaluated the outcomes of ECMO in patients with severe postoperative ARDS.
View Article and Find Full Text PDFRetroesophageal aortic arch, in which the aortic arch crosses the midline behind the esophagus to the contralateral side, is a rare form of vascular anomaly. The complete form may cause symptoms by compressing the esophagus or the trachea and need a surgical intervention. We report a rare case of a hypoplastic left heart syndrome variant with the left retroesophageal circumflex aortic arch in which the left aortic arch, retroesophageal circumflex aorta, and the right descending aorta with the aberrant right subclavian artery encircle the esophagus completely, thus causing central bronchial compression.
View Article and Find Full Text PDFWe demonstrate a cost-effective top-down approach for fabricating InGaN/GaN nanorod arrays using a wet treatment process in a KOH solution. The average diameter of the as-etched nanorods was effectively reduced from 420 nm to 180 nm. The spatial strain distribution was then investigated by measuring the high-resolution cathodoluminescence directly on top of the nanorods.
View Article and Find Full Text PDFInGaN based MQW solar cells have been fabricated with 4 different transparent top electrode structures: (1)- ITO 200 nm, (2)-ITO nano dots only, (3)-ITO nano dots on ITO 50 nm and (4)-ITO nano dots on ITO 100 nm. The solar cell with the ITO 50 nm on ITO nano dots under AM 1.5 conditions showed the best results: 2.
View Article and Find Full Text PDFKorean J Thorac Cardiovasc Surg
December 2012
A 51-year-old male with sustained fever was diagnosed with military tuberculosis and tuberculous aortitis complicated with pseudoaneurysm formation at the proximal descending aorta. A follow-up computed tomography evaluation showed an increased size of the pseudoaneurysm in this area, suggestive of a contained rupture. Consequently, the patient underwent emergency excision and replacement of the aorta using a left heart bypass.
View Article and Find Full Text PDFInGaN based MQW solar cells have been fabricated with 4 different transparent top electrode structures: (1)- ITO 200 nm, (2)-ITO nano dots only, (3)-ITO nano dots on ITO 50 nm and (4)-ITO nano dots on ITO 100 nm. The solar cell with the ITO 50 nm on ITO nano dots under AM 1.5 conditions showed the best results: 2.
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