The MQWs were grown on c-plane sapphire substrate by metal-organic chemical vapor deposition (MOCVD). HRXRD and RSM revealed that the MQWs are coherently strained on the GaN base layer and the coherence remains intact after annealing at temperatures up to 1100 degrees C. They also revealed an occurrence of In/Ga atoms interdiffusion across the QW interfaces at elevated temperatures. The shift in PL emissions towards their lower-energy sides with increasing annealing temperatures provides evidence for the enhanced formation of In-rich regions (quantum dots, QDs) within the QWs.

An anomalous photon-energy dependence of PL lifetimes is observed at 5 K; however, the dependence reverts to normal when the temperature is increased LBH589 to 200 K. This optical transition behavior is discussed based on the self-forming of QDs due to the enhanced In-clustering at elevated temperatures and the anneal-induced generation/activation of defects/impurities-related recombination centers. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3638703]“
“Purpose: The

purpose of this retrospective study was to determine the overall success of short dental implants (8 mm in length) placed in the partially or completely find more edentulous posterior mandible restored with fixed and removable prostheses.

Patients and Methods: A total of 124 patients had 335 8-mm-long implants placed from May ML323 datasheet 2005 until June 2007. Of the 124 total patients, 35 were men and 89 were women, with a median age of 56 years and an age range of 18 to 80 years at the time of implant surgery. There were 112 patients who were partially edentulous and 12 who were completely edentulous. Of the patients,

32 had a single implant placed whereas the other 92 had multiple implants placed. One patient had the implants immediately provisionally loaded. All of the implants were restored by use of fixed prostheses. Of these fixed prostheses, 245 were splinted together whereas 75 were restored individually.

Results: A total of 335 short dental implants were placed in 124 patients. Of the 335 implants placed, 331 integrated successfully. In the 2 cases that failed, the sites were grafted with porous hydroxyapatite and platelet-rich plasma. The implants were replaced at 5 months after the initial failure in the first patient and at 7 months in the second patient. These replacement implants integrated and have been restored and in function for more than 16 months. There was I fracture of an implant with a restoration. The implant had been restored with an individually fabricated fixed restoration, with the fracture occurring at the head of the implant, requiring removal.