We report a simple and low-cost fabrication of antireflection subwavelength grating (SWG) structures on GaAs using the lenslike shape transfer by a holographic lithography and a reflowed photoresist mask. The use of an additional thermal reflow process enhances the close packing of two-dimensional SWGs with a conical shape. The aspect ratio of conical SWG was also controlled easily by adjusting the rf power during the dry etch process. The fabricated SWGs exhibited low reflection properties over a wide spectral range, in agreement with the calculated values using by a rigorous coupled-wave analysis simulation.

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The incidence of infective endocarditis in children is 1.3 cases per 1,000 children who had been admitted. Recognizing infective endocarditis is very important because regardless of prolonged antibiotic treatment, it can entail serious complications, resulting in high morbidity and mortality. One of the important complications is the rupture of Valsalva sinus. We report a case of delayed rupture of the sinus of Valsalva in a 15-year-old boy with subarterial ventricular septal defect complicated with infective endocarditis. Physician must consider the possibility of delayed rupture of the sinus of Valsalva after infective endocarditis although initial evaluations revealed no evidence of periannular extension of infection and of perforation or rupture. 증 례생후 2개월 때 시행한 심장초음파 검사에서 대혈관 판하