Matrix Product States: Entanglement, Symmetries, and State Transformations.

We analyze entanglement in the family of translationally invariant matrix product states (MPS). We give a criterion to determine when two states can be transformed into each other by local operations with a nonvanishing probability, a central question in entanglement theory. This induces a classification within this family of states, which we explicitly carry out for the simplest, nontrivial MPS.

Entangled Pure State Transformations via Local Operations Assisted by Finitely Many Rounds of Classical Communication.

We consider generic pure n-qubit states and a general class of pure states of arbitrary dimensions and arbitrarily many subsystems. We characterize those states which can be reached from some other state via local operations assisted by finitely many rounds of classical communication (LOCC_{N}). For n qubits with n>3, we show that this set of states is of measure zero, which implies that the maximally entangled set is generically of full measure if restricted to the practical scenario of LOCC_{N}.

Operational Multipartite Entanglement Measures.

We introduce two operational entanglement measures that are applicable for arbitrary multipartite (pure or mixed) states. One of them characterizes the potentiality of a state to generate other states via local operations assisted by classical communication and the other characterizes the simplicity of generating the state at hand. We show how these measures can be generalized to two classes of entanglement measures.

Penile prosthetic surgery in neurologically impaired patients: long-term followup.

Purpose: Penile prosthetics are a viable option for erectile dysfunction in neurologically impaired patients. Penile implants can also be used to facilitate the management of urinary drainage when penile retraction has made this difficult.

Materials And Methods: Between 1980 and 1996, 245 neurologically impaired patients with a mean age of 40.

Spastic bladder and spinal cord injury: seventeen years of experience with sacral deafferentation and implantation of an anterior root stimulator.

Introduction: Spinal cord injured patients with a suprasacral lesion usually develop a spastic bladder. The hyperreflexia of the detrusor and the external sphincter causes incontinence and threatens those patients with recurrent urinary tract infections (UTI), renal failure, and autonomic dysreflexia. All of these severe disturbances may be well managed by sacral deafferentation (SDAF) and implantation of an anterior root stimulator.