Polycrystalline films of CdTe have been deposited on graphite substrates, and homoepitaxial films on single-crystal CdTe:P substrates, with hole densities as high as 1.5×1016 cm−3 without intentional doping of the films, using close-spaced vapor transport. The dependence of hole density in the films on the properties of the source, the properties of the substrate, the growth rate, and the substrate temperature, indicates that the doping of the films is the result of a complex interaction between out-diffusion of mobile impurities (if present) from the substrate and intrinsic defects. The capacitance-versus-voltage-indicated hole density decreases slowly with time under a Schottky barrier, but not at a free film surface or under a CdS/CdTe heterojunction. CdS/CdTe solar cells have been prepared using these films, with solar efficiencies greater than 6%. The junction properties of CdS/CdTe heterojunctions are compared with those of In/CdTe Schottky barriers as a function of temperature; transport is dominated by tunneling below room temperature and by interface recombination above room temperature.

We have investigated characteristics of polycrystalline diamond thin films formed by plasma-enhanced chemical vapor deposition method on silicon substrates using Raman spectroscopy, analytical and high-resolution transmission electron microscopy techniques. Grains with average size 1 μm in diameter were observed in these films. The Raman spectra from these films contain the strongest peak at 1335 cm−1, providing the characteristic signature for sp3 (diamond) bonding. The broad peak centered around 1550 cm−1 is believed to be due to some graphitic bonding. From detailed high-resolution images and microdiffraction, films were characterized to be cubic diamond with a lattice parameter of 3.56 Å. Diamond crystallites with fivefold external morphologies were also observed. The large crystallites in the films exhibited preferential texture in 〈011〉 type orientations. These crystallites were found to be twinned in {111} planes. The large 〈011〉 crystallites exhibited matching in {111} or {200} lattice planes of diamond with {022} planes of silicon. This is in agreement with our previous work on the growth of Ni on MgO, which showed that textured growth can occur by matching a set of lattice planes in the absence of matching of lattice constants.

Notch signaling expression in regenerating muscle following injurious downhill running (DHR) was characterized in male C57BL/J6 mice (3 mo). Hindlimb muscles were harvested from control mice or at 24, 48, 72, 96 or 120 h post-DHR. Muscle injury was observed at 96 h (3.3-fold) and 120 h (3.7-fold) post-DHR (P < 0.01) and elevated MCadherin expression at 72 h (2.7-fold), 96 h (2.4-fold) post-DHR (P < 0.05) and 120 h (3.3-fold) post-DHR (P < 0.01). Desmin increased at 72 h (2.2-fold), 96 h (3-fold) and 120 h (1.8-fold) post-DHR (P < 0.05). Delta1 +/MCadherin + cells increased approximately 2-fold at 72, 96 (P < 0.01) and 120 h post-DHR (P < 0.05). Isolated muscle-associated cells increased Delta1 (2.6-fold) (P < 0.05) and Notch1 (fourfold) (P < 0.01) expression at 120 h post-DHR. The results of this novel study indicate that DHR up-regulates Notch components within myoblasts and regenerating muscle.

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