Las Vegas – The boarded-up Queen of Hearts is open to gamblers again, but only for eight hours. It’s a periodic Vegas ritual that lets closed operations retain their gaming rights — and property values. The small casino is ringed with a fence topped with barbed wire. Its beige walls have browned from the punishing desert sun. Its bulbous canopies are torn, and the marquee is missing vowels. The front door is padlocked.