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.
Scott Joplin is regarded by most as the King of Ragtime Writers, in part due to his early success with the best-selling Maple Leaf Rag (below) but more importantly due to the enduring nature and quality of his ragtime compositions.