We mourn the loss of disco diva and five-time Grammy winner Donna Summer, whose anthems like “Last Dance” and “Hot Stuff” helped define an era.   She died at age 63 from cancer.  Her songs were featured in a number of movies, most memorably in “The Full Monty,” “Roll Bounce,” “Zoolander,” and “Charlie Wilson’s War” as well as episodes of “Sex and the City” and “The Simpsons.”  Born LaDonna Adrian Gaines, she performed in the European cast of the original production of “Hair,” sang in a rock band, and was a back-up singer for Three Dog Night.  Her powerful voice was perfect for the disco era, when she became the first artist to have three consecutive double albums reach number one on the US Billboard chart.  May her memory be a blessing.