Thiazole fused ,-heteroacene step-ladder polymeric semiconductors for organic transistors.

Ladder-type thiazole-fused ,-heteroacenes with an extended π-conjugation consisting of six (SN6-Tz) and nine (SN9-Tz) fused aromatic rings have been synthesized and fully characterized. To date, the synthesis of well-defined fused building blocks and polymers of π-conjugated organic compounds based on the thiazole moiety is a considerable synthetic challenge, due to the difficulty in their synthesis. Acceptor-donor building blocks M1 and M2 were successfully polymerized into ladder homopolymers P1-P2 and further copolymerized with a diketopyrrolopyrrole unit to afford step-ladder copolymer P3.

Standard OSEM vs. regularized PET image reconstruction: qualitative and quantitative comparison using phantom data and various clinical radiopharmaceuticals.

We investigated the block sequential regularized expectation maximization (BSREM) algorithm. ACR phantom measurements with different count statistics and 60 PET/CT research scans from the GE Discovery 600 and 690 scanners were reconstructed using BSREM and the standard-of-care OSEM algorithm. Hot concentration recovery and cold contrast recovery were measured from the phantom data.