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We proposed a neural network model trained with a small amount of meniscus data (only 144 MR images) to improve the segmentation performance of CNNs, such as U-Net, by overcoming the challenges caused by surrounding tissues. We trained and tested the proposed model on 204 T2-weighted MR images of the knee from 181 patients. The trained model provided excellent segmentation performance for lateral menisci with a mean Dice similarity coefficient of 0.864 (range, 0.743-0.990; SD, ±0.077). The results were superior to those of contemporarily published meniscus segmentation methods based on CNNs.

A computational study has been performed to investigate the mechanism of RhIII‐catalyzed C−H bond activation using sulfoxonium ylides as a carbene precursor. The stepwise and concerted activation modes for sulfoxonium ylides were investigated. Detailed theoretical results showed that the favored stepwise pathway involves C−H bond activation, carbonization, carbene insertion, and protonation. The free energy profiles for dialkylation of 2‐phenylpyridine were also calculated to account for the low yield of this reaction. Furthermore, the substituent effect was elucidated by comparing the energy barriers for the protonation of meta‐ and para‐substituted sulfoxonium ylides calculated by density functional theory.

Ni-catalyzed alkene intermolecular 1,2-dicarbofunctionalization cross-coupling is an efficient method to construct complex molecules from readily available starting materials. Typically, alkenes are proposed activated by radical addition mode in this cross-coupling...

C−N bond metathesis is a straightforward and step-economical approach for C-N bond construction. Typically, the oxidation state of the transition metal remains unchanged during C−N bond metathesis. In this report,...