Tom Vitale reports on jazz bassist George Mraz, who has accompanied Oscar Peterson, Ella Fitzgerald, Stan Getz and many others. He's also led his own groups. But perhaps his most personal project is his most recent: a collection of jazz arrangements of folk songs from his native Czechoslovakia, a country he did not see for almost a quarter century after the Soviets invaded. The CD is called Morava. It's on the Milestone record label, catalog number MCD 9309-2.