Reflection algebra, Yangian symmetry and bound-states in AdS/CFT
  We present the `Heisenberg picture' of the reflection algebra by explicitly constructing the boundary Yangian symmetry of an AdS/CFT superstring which ends on a boundary with non-trivial degrees of freedom and which preserves the full bulk Lie symmetry algebra. We also consider the spectrum of bulk and boundary states and some automorphisms of the underlying algebras. 
Niall MacKay and Vidas Regelskis
hep-th math.QA