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The left mandibular premolars were extracted from five adult dogs. After twelve weeks, a box-shaped osteotomy of the alveolar bone was carried out and two 10 mm implants were placed 5 mm into the transport alveolar segment, leaving 5 mm exposed. The alveolar bone was vertically augmented 5 mm by screwing the implants. After distraction, the implants were left to integrate into the bone. Histological and radiographical evaluations showed the lifting of the transport segment and the development of new bone in the distraction area. Although integration of implants within both the transport segment and the regenerated bone was observed, two of the ten implants failed and partial bone resorption of the transport segment was noted.

The citric acid‐hydrogen peroxide‐water system has been developed for preferential etching of normalGaAs through photoresist masks. Etching rates depend strongly on the composition of the solution and on the crystal orientation of normalGaAs , with the rates in the order (111)B > (100) > (111)A. Flat‐bottomed holes were obtained for all compositions of the solutions. The solution does not erode photoresist masks, thereby providing preferential etching of normalGaAs through such masks.

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The excited-state dynamics of pyrene incorporated into poly­(substituted methylene)­s is investigated by picosecond time-resolved fluorescence spectroscopy and femtosecond time-resolved near-IR absorption spectroscopy in the 900–1400 nm region. The pyrene rings in poly­(substituted methylene)­s are photoexcited to the monomer excited state immediately after UV irradiation, followed by prompt excimer formation with time constants of a few picoseconds to a few hundred picoseconds. The excimer formation in poly­(substituted methylene)­s proceeds with much shorter time constants than that in pyrene-incorporated polyacrylates, vinyl polymer counterparts with the same side-chain structures, indicating the presence of stronger electronic interaction between the pyrene rings in poly­(substituted methylene)­s. The effects of every methylene substitution hold when each pyrene ring is connected to the polymer backbone with a monomethylene linker, while the effects are observed only weakly when a tetramethylene linker is employed. The results demonstrate the effectiveness of every methylene substitution in the prompt excimer formation of pyrene connected to the polymer backbone either directly or with the monomethylene linker.