br A controversial new law in Denmark, Europe's ongoing refugee crisis, and a retrospective on the "Arab Spring" are covered first this Wednesday on CNN Student News. Then, it's time for the second half of our two-part series on transportation, and we're taking a ride on a new type of magnetic train. Finally, get a sense of how a compliment compares to a cash prize in terms of how the brain processes it -- and how positive reinforcement can help us learn while we sleep.