Helmer Jeff Nichols’ psychological drama “Take Shelter” beat 13 other contenders to win the grand prize at the 37th Deauville American Film Festival, which wrapped Saturday.Pic, starring Michael Shannon as a man struggling with mental illness, won Cannes’ Critics Week in May and screened in competition at Sundance. It segues to Toronto this week. Ad Vitam will release the film on Dec. 7 in France. Presided over by French helmer Olivier Assayas, the jury awarded its prize to Matthew Gordon’s coming-of-age drama “The Dynamiter,” one of the competition’s nine directorial debuts. Lensed in Mississippi, pic follows a teen taking care of his younger half-brother after they are abandoned by their mother for the summer. “The Dynamiter” is seeking theatrical distribution. Gordon is currently producing documentary “Layoffs On Wall Street: Bankers in Their Own Words,” directed by his wife, Marianne Michallet, who exec produced “The Dynamiter.” Tony Kaye’s “Detachment,” starring Adrien Brody and Christina Hendricks, nabbed the Fipresci international critics prize and the Revelation nod. Tribeca Film has U.S. distribution rights; Pretty Pictures distributes in Gaul. Deauville closed with Michel Hazanavicius’ silent film “The Artist,” starring Jean Dujardin.