Fresh Air Weekend: Yo-Yo Ma; Actor Griffin Dunne toggle caption Larry French/Getty Images North America Fresh Air Weekend highlights some of the best interviews and reviews from past weeks, and new program elements specially paced for weekends. This week: Yo-Yo Ma on ‘touching infinity’ through his nearly 300-year-old cello, Petunia: About 25 years ago, acclaimed cellist Yo-Yo Ma asked a …