Mary Heilmann’s red and black ceramic sculpture ‘Curl’ seems to defy its title with its angular panels, yet each segment dynamically spins around a central core like a step on a spiral staircase seen from above. Each tile evokes a riser with three treads or a chunky version of the Egyptian deity Isis’ throne in Constructivist colors that make a bold statement. (On view at Gladstone Gallery’s 24th Street Chelsea location through July 26th).