The Pittsburgh Symphony Orchestra performs two world premieres, plus music of Smetana, Schumann and Stravinsky this weekend at Heinz Hall.  WQED-FM's Jim Cunningham spoke to composer Reza Vali about his brand new piece ""The Girl from Shiraz" from Persian Folk Songs, which features as soloist, Kian Soltani.  Kian also joins the conversation to talk about the Reza Vali piece, as well as playing the Schumann Cello Concerto.