Alloyed PtM (M = Co, Ni) nanoparticles supported on S- and N-doped carbon nanotubes for the oxygen reduction reaction.

Sulfur- (S-CNT) and nitrogen-doped (N-CNT) carbon nanotubes have been produced by catalytic chemical vapor deposition (c-CVD) and were subject to an annealing treatment. These CNTs were used as supports for small (≈2 nm) PtM (M = Co or Ni) alloyed nanoparticles that have a very homogeneous size distribution (in spite of the high metal loading of ≈40 wt % Pt), using an ionic liquid as a stabilizer. The electrochemical surface area, the activity for the oxygen reduction reaction and the amount of HO generated during the oxygen reduction reaction (ORR) have been evaluated in a rotating ring disk electrode experiment.

Posterior "back and forth" approach in arthroscopic surgery on the posterior knee compartments.

We report the feasibility, indications, and usefulness of an arthroscopic approach to the posterior knee compartments. We developed an arthroscopic approach to the posterior knee compartment involving use of a posteromedial portal and a posterolateral portal opposite each other. Each posterior portal is used in alternation for the arthroscope and instruments.