精灵宝可梦太阳 月亮

视频简介

NOVA: Mysteries of Sleep Like virtually every other animal, humans need sleep to survive. But why? What do we gain from spending nearly a third of our lives in such a defenseless state? And what's at stake if we sleep poorly? The functions of sleep have long been something of a mystery. But now scientists are peering deep into the brain to see what happens while we snooze. One ...。During the 1977 El Salvadoran presidential election, public unrest is at an all-time high over fears of election fraud. In the midst of a Marxist-Leninist guerrilla insurgency by the Farabundo Martí National Liberation Front, the anti-communist military dictatorship uses death squads to abduct, torture and "disappear" anyone who speaks about their terrible human rights record. ...。