An terior cerebral artery A1 segment hypoplasia is an uncom-. mon fetal variant of the circle of Willis. The frequency of this. congenital variation is 1â13% as derived from angiograms. and autopsy reports. Impaired collateral blood flow through. the circle of Willis is a recognized risk factor for ischemic. stroke. The A1 segment of the anterior cerebral artery is a. principal supplier of anterior collateral blood flow.
George Washington, 1799. Printer Friendly Version >>>. George Washington finished his second term as the first President of the United States in 1797. Weary of the political infighting surrounding the presidency, he longed for the peace of retirement to his beloved Mount Vernon.
George Washington was the first president of the United States, Commanding General during the American Revolution and remains as one of the most influential and famous figures in American history. His contribution extends far beyond perhaps any other in the history of the United States. He was involved twice in Germantown's contribution to American history. In 1777 during the Revolution he led the American Army in the Battle of Germantown. In 1793 to escape the Yellow Fever Epidemic, the capitol was moved from Philadelphia to Germantown.