ABSTRACT
Detailed geodetic imaging of earthquake ruptures enhances our understanding of earthquake physics and associated ground shaking. The 25 April 2015 moment magnitude 7.8 earthquake in Gorkha, Nepal was the first large continental megathrust rupture to have occurred beneath a high-rate (5-hertz) Global Positioning System (GPS) network. We used GPS and interferometric synthetic aperture radar data to model the earthquake rupture as a slip pulse ~20 kilometers in width, ~6 seconds in duration, and with a peak sliding velocity of 1.1 meters per second, which propagated toward the Kathmandu basin at ~3.3 kilometers per second over ~140 kilometers. The smooth slip onset, indicating a large (~5-meter) slip-weakening distance, caused moderate ground shaking at high frequencies (>1 hertz; peak ground acceleration, ~16% of Earth's gravity) and minimized damage to vernacular dwellings. Whole-basin resonance at a period of 4 to 5 seconds caused the collapse of tall structures, including cultural artifacts.
ABSTRACT
A survey of school children aged 5 to 16 years living in a rural community of the hill region of Nepal, situated about 15-22 km outside Kathmandu city, was conducted to determine the prevalence of rheumatic fever (RF) and rheumatic heart disease (RHD). Of the 4,816 eligible children enrolled in the selected schools, 4,452 (92.4%) were examined. WHO expert committee criteria (1966) was used for the diagnosis and classification of rheumatic fever. Chest x-ray, electro-cardiography, echocardiography and Doppler study were done in all suspected cases of rheumatic heart disease. Six cases of RHD (1 pure mitral stenosis, 3 mitral regurgitation and 2 combined mitral stenosis and regurgitation) were identified giving overall prevalence rate of 1.35 per thousand. No case with active rheumatic fever could be identified. This is the first study on prevalence of RF/RHD in Nepal. The prevalence rate is lower than that reported from neighbouring countries.
