RESUMO
Side chain engineering of conjugated donor-acceptor polymers is a new way to manipulate their optoelectronic properties. Two new diketopyrrolopyrrole (DPP)-terthiophene-based conjugated polymers PDPP3T-1 and PDPP3T-2, with both hydrophilic triethylene glycol (TEG) and hydrophobic alkyl chains, are reported. It is demonstrated that the incorporation of TEG chains has a significant effect on the interchain packing and thin-film morphology with noticeable effect on charge transport. Polymer chains of PDPP3T-1 in which TEG chains are uniformly distributed can self-assemble spontaneously into a more ordered thin film. As a result, the thin film of PDPP3T-1 exhibits high saturated hole mobility up to 2.6 cm2 V-1 s-1 without any post-treatment. This is superior to those of PDPP3T with just alkyl chains and PDPP3T-2. Moreover, the respective field effect transistors made of PDPP3T-1 can be utilized for sensing ethanol vapor with high sensitivity (down to 100 ppb) and good selectivity.
RESUMO
BACKGROUND: Because the course and territory of perforators are different in each region, careful preoperative planning to identify the proper perforators can be critical to ensure a successful dissection of a freestyle pedicled perforator flap. In this study, our first experience for preoperative perforator mapping of a freestyle pedicled perforator flap using multidetector row computed tomography (MD-CT) angiography is presented. METHODS: Twelve patients were planned to undergo various soft-tissue reconstructions with freestyle pedicled perforator flaps. They were evaluated with preoperative MD-CT angiography. The OsiriX for mac software was used to process the data obtained from MD-CT angiography. The available images from MD-CT angiography were analyzed to determine where the proper perforators were located for preoperative planning of a freestyle pedicled perforator flap. Through the MD-CT angiography, the optimal perforators were mapped and a reliable flap design could be made so that the flap was elevated more safely and perfectly to cover an adjacent soft-tissue defect. RESULTS: In all 12 patients, each flap was elevated successfully based on the perforators mapped preoperatively with MD-CT angiography. A total of 27 perforators (1-3 perforators per flap) were identified by MD-CT angiography in 12 patients and later confirmed during the flap dissection (sensitivity, 100%). CONCLUSIONS: The MD-CT angiography can be a new but very effective imaging modality for preoperative planning of a freestyle pedicled perforator flap surgery. It allows surgeons to accurately select the most appropriate perforators with the shortest intramuscular or suprafascial course preoperatively leading to safer and easier flap dissection.