Branch Retinal Artery Occlusion - Pathophysiology. 1  Most commonly, a branch retinal artery occlusion occurs secondary to an embolus. Emboli typically originate within vessels upstream where they dislodge and travel within the circulatory system to ultimately become lodged downstream in a vessel with a smaller lumen.
Ragtime is a musical form or style that is defined as a syncopated melody (usually in 2/4 time) over a regular, march tempo bass line. Improvisation was common but little of that aspect has been preserved.
This informal folk music became formalised into Ragtime by composers like Harney and Joplin who played the music to large audiences and published it so that its popularity spread across the country. A Brief History of Ragtime