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A structured skills curriculum using fresh cadavers improved participants' self-confidence in operative skills required for surgical exposure of human anatomic structures for trauma. This model of training may be beneficial for surgical residents and fellows, as well as practicing trauma surgeons.

In the presence of several Pd(II) catalysts, cis-bicyclo[4.2.0]oct-7-ene (4a) was found to undergo olefin isomerization ("ring walking") and oligomerization, resulting in the formation of cis-bicyclo[4.2.0]oct-2-ene (4d) and the low-molecular-mass cycloaliphatic oligomers 5a−d, respectively. The catalysts studied are [Pd(NCEt) 6), and [(2,9-dimethyl-1,10-phenanthroline)Pd(CH 3 )(NC(CH 2 ) 6 CH 3 )][SbF 6 ] (7). Isomerization included the formation of both 4d and the olefinic end groups of 5a−d and ranged from 94% using catalyst 7 to 29% employing catalyst 2. Ab initio and DFT calculations at the LMP2/6-31G** and B3LYP/6-31G** levels show that the thermodynamic stabilities of the bicyclo[4.2.0]octene isomers increase in the order 7-ene 4a < 1(8)-ene 4b < 1-ene 4c ≈ 1(6)-ene 4e ≈ 3-ene 4f < 2-ene 4d. A mechanism of isomerization via subsequent β-hydride eliminations and olefin reinsertions is proposed. These results are in contrast to the reactions of bicyclo[3.2.0]hept-6-ene (3a) catalyzed by 1, 2, and 7 and the reaction of 4a catalyzed by Cp 2 ZrCl 2 / MAO (Cp = η 5 -C 5 H 5 ), all of which produced polymers in good yields (73−99%).