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An intermolecular annulation reaction of 2‐aryl‐1,3‐indandions with alkynes was reported using Pd(OAc)2 to access spirobi[indene]‐1,3‐diones. Under palladium catalysis, the substrates form a homocoupling dimer intermediate through a catalytic dehydrogenative cross‐coupling process. The palladium(II) species could come from dimer or 2‐aryl‐1,3‐indandion. Notably, this pathway is not typically observed in enol‐directed formal sp3 C−H functionalization/oxidative annulation palladium chemistry. This transformation provides a route to access a class of functionalized spiro carbocyclic indenes. [ABSTRACT FROM AUTHOR]

An electrochemically enabled tandem cyclization reaction of unsaturated sulfoximines with diselenides has been well developed, affording metal‐ and external oxidant‐free access to sulfoximidoyl‐based heterocycles containing selenium in moderate to good yields. With nBu4NBr as the role of catalyst and electrolyte, this methodology shows broad substrate scope and functional group tolerance under mild conditions. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method that uses the idea of decoupling and unites edge information for semantic segmentation. We build a new dual-stream CNN architecture that fully considers the interaction between the body and the edge of the object, and our method significantly improves the segmentation performance of small objects and object boundaries. The dual-stream CNN architecture mainly consists of a body-stream module and an edge-stream module, which process the feature map of the segmented object into two parts with low coupling: body features and edge features. The body stream warps the image features by learning the flow-field offset, warps the body pixels toward object inner parts, completes the generation of the body features, and enhances the object's inner consistency. In the generation of edge features, the current state-of-the-art model processes information such as color, shape, and texture under a single network, which will ignore the recognition of important information. Our method separates the edge-processing branch in the network, i.e., the edge stream. The edge stream processes information in parallel with the body stream and effectively eliminates the noise of useless information by introducing a non-edge suppression layer to emphasize the importance of edge information. We validate our method on the large-scale public dataset Cityscapes, and our method greatly improves the segmentation performance of hard-to-segment objects and achieves state-of-the-art result. Notably, the method in this paper can achieve 82.6% mIoU on the Cityscapes with only fine-annotated data. [ABSTRACT FROM AUTHOR]

Millepachine, a bioactive natural product isolated from the seeds of Millettia pachycarpa, is reported to display potential antitumor activity. In this study, novel indole-containing hybrids derived from millepachine were designed, synthesized and evaluated for their antitumor activities. Among all the compounds, compound 14b exhibited the most potent cytotoxic activity against five kinds of human cancer cell lines, with IC50 values ranging from 0.022 to 0.074 μM, making it almost 100 times more active than millepachine. Valuable structure–activity relationships (SARs) were obtained. Furthermore, the mechanism studies showed that compound 14b induced cell-cycle arrest at the G2/M phase by inhibiting tubulin polymerization and further induced cell apoptosis through reactive oxygen species (ROS) accumulation and mitochondrial membrane potential (MMP) collapse. In addition, the low cytotoxicity toward normal human cells and equivalent sensitivity towards drug-resistant cells of compound 14b highlighted its potential for the development of antitumor drugs. [ABSTRACT FROM AUTHOR]

We report on the first, to the best of our knowledge, simultaneous continuous-wave red, green and blue laser operations in praseodymium-doped crystalline materials. At an absorbed pump power of 4.7 W (or 10 W of incident pump power), the maximum output power was 665 mW, which included 607 nm (red), 523 nm (green) and 479 nm (blue) three wavelengths, and the optical conversion efficiency with respect to the absorbed pump power was 14.1%. [ABSTRACT FROM AUTHOR]