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ObjectiveThe objective of this study was to evaluate the effectiveness of the treatment of infected nonunion of tibia and femur by bone transport.Material and methodsWe retrospectively reviewed 110 patients with infected nonunion of tibia and femur treated by bone transport. Our study included 92 males and 18 females with a mean age of 38.90 years. The site of infected nonunion involved 72 tibias and 38 femurs. The mean length of the bone defects after radical debridement was 6.15 cm (range 3–13 cm).ResultsThe mean follow-up after removal of the apparatus was 23.12 months (14–46 months). Ten patients including seven patients with infected tibia nonunion and three patients with infected femur nonunion were lost to follow-up. All the patients achieved bone union, and no recurrence of infection was observed. The time of bone transport took a mean of 67.50 days (range 33 to 137 days), and the mean external fixation index was 1.48 months/cm (range 1.15–1.71 months/cm). According to Association for the Study and Application of the Method of Ilizarov (ASAMI) classification, bone results were excellent in 68, good in 28, fair in 12, and poor in 2; functional results were excellent in 37, good in 42, fair in 21, and no poor.ConclusionsOur study and the current evidence suggested that Ilizarov methods in the treatment of infected nonunion of tibia and femur acquired satisfied results. Radical debridement is the key step to control bone infection.

We demonstrated a new comprehensive method to combine scanning probe microscopy (SPM) nanolithography and modified SPM break junction techniques to fabricate and characterize single molecular break junction devices. By patterning alkanedithiol and alkanediamine molecules in the alkanethiol template and measuring the conductance of the two kinds of molecular junctions, we have shown the following: (1) the new "stretch-hold" approach produced four groups of conductance values for each molecular junction, for the first time realizing the less populated conductance values that correspond to different contact configurations; (2) the electronic transport mechanism for such molecular junctions is electronic tunneling with similar decay constants for each conductance group of the same kind of molecules. The conductance differences among different groups are due to the molecule-electrode contact configuration difference, which was shown by the extrapolated contact resistances. This new approach also allows one to eliminate, or at least minimize, the variations of experimental conditions and enables the measurement of multiple molecules under the same experiment with exactly the same experimental conditions.

We report on a theoretical analysis and experimental verification of a mechanism for photoconductance, the change in conductance upon illumination, in symmetric single-molecule junctions. We demonstrate that photoconductance at resonant illumination arises due to the Coulomb interaction between the electrons and holes in the molecular bridge, so-called exciton-binding. Using a scanning tunneling microscopy break junction technique, we measure the conductance histograms of perylene tetracarboxylic diimide (PTCDI) molecules attached to Au-electrodes, in the dark and under illumination, and show a significant and reversible change in conductance, as expected from the theory. Finally, we show how our description of the photoconductance leads to a simple design principle for enhancing the performance of molecular switches.

A lateral heterojunction of topological insulator Sb2Te3/Bi2Te3 was successfully synthesized using a two-step solvothermal method. The two crystalline components were separated well by a sharp lattice-matched interface when the optimized procedure was used. Inspecting the heterojunction using high-resolution transmission electron microscopy showed that epitaxial growth occurred along the horizontal plane. The semiconducting temperature-resistance curve and crossjunction rectification were observed, which reveal a staggered-gap lateral heterojunction with a small junction voltage. Quantum correction from the weak antilocalization reveals the well-maintained transport of the topological surface state. This is appealing for a platform for spin filters and one-dimensional topological interface states.