Generalized nucleus segmentation techniques can contribute greatly to reducing the time to develop and validate visual biomarkers for new digital pathology datasets. We summarize the results of MoNuSeg 2018 Challenge whose objective was to develop generalizable nuclei segmentation techniques in digital pathology. The challenge was an official satellite event of the MICCAI 2018 conference in which 32 teams with more than 80 participants from geographically diverse institutes participated. Contestants were given a training set with 30 images from seven organs with annotations of 21,623 individual nuclei. A test dataset with 14 images taken from seven organs, including two organs that did not appear in the training set was released without annotations. Entries were evaluated based on average aggregated Jaccard index (AJI) on the test set to prioritize accurate instance segmentation as opposed to mere semantic segmentation. More than half the teams that completed the challenge outperformed a previous baseline [1]. Among the trends observed that contributed to increased accuracy were the use of color normalization as well as heavy data augmentation. Additionally, fully convolutional networks inspired by variants of U-Net [2], FCN [3], and Mask- RCNN [4] were popularly used, typically based on ResNet [5] or VGG [6] base architectures. Watershed segmentation on predicted semantic segmentation maps was a popular post-processing strategy. Several of the top techniques compared favorably to an individual human annotator and can be used with confidence for nuclear morphometrics.

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Silicon (Si) and carbon (C) composites hold the promise for replacing the commercial graphite anode, thus increasing the energy density of lithium‐ion batteries (LIBs). To mitigate the formation of SiC, this paper reports a molten salt electrolysis approach to prepare C‐Si composite by the electrolysis of C‐SiO2 composites. Unlike the conventional way of making a C coating on Si, C‐SiO2 composites were prepared by pyrolyzing the low‐cost sucrose and silica. The electrochemical deoxidation of the C‐SiO2 composites not only produces nanostructured Si inside the C matrix but also introduces voids between the C and Si owing to the volume shrinkage from converting SiO2 to Si. More importantly, the use of Mg ion‐containing molten salts precludes the generation of SiC, and the electrolytic Si@C composite anode delivers a capacity of about 1500 mAh g−1 after 100 cycles at a current density of 500 mA g−1. Further, the Si@C|| LiNi0.6Co0.2Mn0.2O2 full cell delivers a high energy density of 608 Wh kg−1. Overall, the molten salt approach provides a one‐step electrochemical way to convert oxides@C to metals@C functional materials.

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Fabricating hollow space between a Si core and C shell has been recognized as an efficient strategy for tailoring lithium-storage performances of the silicon–carbon composite anode by resolving the extreme volume expansion of Si. Here, we report a molten-salt electrolysis method for electroreducing carbon-encapsulated magnesium silicate to prepare a Si@void@C composite in MgCl2-containing molten salt. The void space between carbon and silicon comes from the transition from silicate to Si as well as the removal of the in situ generated MgO, and the SiC is suppressed by tailoring the electrode potentials in MgCl2-containing molten salt. In other words, MgO serves as an inert space holder that can be removed by an acid leaching process to create void space. The obtained Si@void@C composite delivers a specific discharge capacity of 900 mAh/g at 1 A/g, even after 300 cycles with a discharge capacity retention rate of 75.5%. Therefore, this study paves an electrochemical pathway to prepare Si@void@C composite anodes using inexpensive feedstocks, and the void space can be tuned by adjusting the amount of MgO space holder.

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Liquid metal batteries (LMBs), with the merits of long lifespan and low cost, are deemed as one of the most promising energy storage technologies for large-scale energy storage applications due to the use of liquid metal electrodes and molten salt electrolytes. However, the consequent problem is that the poor wettability between graphite-based collectors and the liquid metal/alloy electrodes leads to large contact resistance, which limits the efficiency and stability of the battery. In this work, a transition layer in situ formed on a graphite-based positive electrode current collector by Ti additive is designed for the first time, which increases the wettability between the positive alloy and the current collector and improves the voltage efficiency of the Li||Sb-Sn cell from 85.6 to 88.4%. These results provide new ideas for the design of high-efficiency LMBs.

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