The short-term results of short segmental fixation without fusion for surgically treated burst fractures of the thoracolumbar spine were satisfactory. The advantages of instrumentation without fusion are the elimination of donor site complications, saving more motion segments, and reducing blood loss and operative time.

Our report is the first prospective, single-blinded, randomized study to evaluate the clinical effectiveness of dilute betadine solution irrigation for prevention of wound infection following spinal surgery. We recommended this simple and inexpensive measure following spinal surgery, particularly in patients with accidental wound contamination, risk factors for wound infection, or undergoing surgery in the absence of routine ultraviolet light, laminar flow, and isolation suits.

We have investigated the influence of nuclear geometric relaxation on the extent of the excited-state electronic delocalization in conjugated zinc porphyrin oligomers using ultrafast transient photoluminescence spectroscopy. By use of metal-coordinating templates that force the oligomers into specific geometries in solution we are able to distinguish clearly between relaxation effects arising from the two vibrational modes that preferentially couple to the electronic transitions in such materials, i.e., carbon-carbon bond stretches and inter-ring torsions. We find that light absorption generates an excited state that is initially strongly delocalized along the oligomer but contracts rapidly following vibrational relaxation of the nuclei along C-C stretch coordinates on the subpicosecond time scale. We are able to monitor such excitonic self-trapping effects by observing the extent to which the concomitant ultrafast rotation of the transition dipole moment is found to correlate with the degree of bending induced in the molecular backbone. We further demonstrate that interporphyrin torsional relaxation leads to a subsequent increase in the excited-state electronic delocalization on a longer time scale (approximately 100 ps). Such dynamic planarization of the molecular backbone is evident from the time-dependent increase in the overall emission intensity and red-shift in the peak emission energy that can be observed for wormlike flexible porphyrin octamers but not for torsionally rigidified cyclic or double-strand octamer complexes. These results therefore indicate that, following excitation, the initially highly delocalized excited-state wave function first contracts and then expands again along the conjugated backbone in accordance with the time periods for the vibrational modes coupled to the electronic transition.

Dedicated to Professor Jeremy Sanders on the occasion of his 60th birthdayBelt-shaped chromophores provide fascinating insights into electronic p delocalization over curved surfaces with radially oriented p orbitals.[1] Examples include the cyclic para-phenylacetylenes [2] and the [4 6 ]paracyclophanedodecayne of Tsuji and coworkers, [3] as well as fullerenes and carbon nanotubes. A variety of belt-shaped porphyrin arrays have been synthesized; [4] however, the vast majority of them lacks a complete pconjugation pathway around the whole macrocycle. Recently we reported the synthesis of a belt-shaped D 8h symmetric porphyrin[8] nanoring on an octadentate template.[5] Herein we present an efficient synthesis of an even more strained p conjugated D 6h porphyrin [6] nanoring 1, by template-directed trimerization of a porphyrin dimer 2 on a hexapyridyl template 3 (Scheme 1). This route is more direct than the synthesis of the cyclic octamer since both starting materials, 2 and 3, are readily accessible. The cyclic hexamer complex 1·3 is phenomenally stable (K f = 7 10 38 m À1 ; EM = 340 m) but the free macrocycle can be liberated from the 1·3 complex with amines such as quinuclidine. The UV/Vis/NIR absorption and emission show that there is efficient p conjugation around the porphyrin[6] nanoring 1, and that its S 0 -S 1 gap is even smaller than that of the corresponding linear porphyrin hexamer 4; this conclusion is supported by time-dependent density functional (TD-DFT) calculations.The key to the synthesis of the hexamer nanoring is the design of a complementary template (Scheme 2). The hexadentate template 3 has a calculated nitrogennitrogen distance of 20.1 , which is a good fit for the cavity of cyclic hexamer 1 with a zinc-zinc ring diameter of 24.2 (assuming a Zn À N bond length of 2.2 ). The template was synthesized by a six-fold Suzuki coupling of 4-pyridineboronic acid with hexakis(4-bromophenyl)benzene [6] in 50 % yield (Supporting Information). Two versions of cyclic hexamer 1 were synthesized-1 a·3 with tert-butyl side chains in 44 % and 1 b·3 with octyloxy side chains in 33 % yield-by oxidative

Diluted povidone-iodine solution can be used safely in spinal surgeries, and it will not influence wound healing, bone union and clinical outcome.