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Background: The process of liver organogenesis has served as a paradigm for organ formation. However, there remains a lack of understanding regarding early mouse and human liver bud morphogenesis and early liver volumetric growth. Elucidating dynamic changes in liver volumes is critical for understanding organ development, implementing toxicological studies, and for modeling hPSC‐derived liver organoid growth. New visualization, analysis, and experimental techniques are desperately needed. Results: Here, we combine observational data with digital resources, new 3D imaging approaches, retrospective analysis of liver volume data, mathematical modeling, and experiments with hPSC‐derived liver organoids. Mouse and human liver organogenesis, characterized by exponential growth, demonstrate distinct spatial features and growth curves over time, which we mathematically modeled using Gompertz models. Visualization of liver‐epithelial and septum transversum mesenchyme (STM) interactions suggests extended interactions, which together with new spatial features may be responsible for extensive exponential growth. These STM interactions are modeled with a novel in vitro human pluripotent stem cell (hPSC)‐derived hepatic organoid system that exhibits cell migration. Conclusions: Our methods enhance our understanding of liver organogenesis, with new 3D visualization, analysis, mathematical modeling, and in vitro models with hPSCs. Our approach highlights mouse and human differences and provides potential hypothesis for further investigation in vitro and in vivo. Key Findings: We developed a new approach that enables quantitative visualization and analysis of mouse and human early liver growth by using available online databases.We identify potentially new spatial features of liver bud growth, and establish the importance of liver‐STM interactions with both imaging/analysis and a novel assay for liver bud migration.Our studies provide a visual and quantitative comparison of liver bud growth. These studies improve our understanding of mouse and human liver organogenesis [ABSTRACT FROM AUTHOR]

The field of organoid engineering promises to revolutionize medicine with wide‐ranging applications of scientific, engineering, and clinical interest, including precision and personalized medicine, gene editing, drug development, disease modelling, cellular therapy, and human development. Organoids are a three‐dimensional (3D) miniature representation of a target organ, are initiated with stem/progenitor cells, and are extremely promising tools with which to model organ function. The biological basis for organoids is that they foster stem cell self‐renewal, differentiation, and self‐organization, recapitulating 3D tissue structure or function better than two‐dimensional (2D) systems. In this review, we first discuss the importance of epithelial organs and the general properties of epithelial cells to provide a context and rationale for organoids of the liver, pancreas, and gall bladder. Next, we develop a general framework to understand self‐organization, tissue hierarchy, and organoid cultivation. For each of these areas, we provide a historical context, and review a wide range of both biological and mathematical perspectives that enhance understanding of organoids. Next, we review existing techniques and progress in hepatobiliary and pancreatic organoid engineering. To do this, we review organoids from primary tissues, cell lines, and stem cells, and introduce engineering studies when applicable. We discuss non‐invasive assessment of organoids, which can reveal the underlying biological mechanisms and enable improved assays for growth, metabolism, and function. Applications of organoids in cell therapy are also discussed. Taken together, we establish a broad scientific foundation for organoids and provide an in‐depth review of hepatic, biliary and pancreatic organoids. [ABSTRACT FROM AUTHOR]

Lithium sulfide (Li2S) has drawn special attention as a promising cathode material for emerging energy storage systems due to its high theoretical specific capacity and great compatibility with lithium metal-free anodes. However, Li2S cathodes urgently require a solution to increase their poor electrical conductivity and to suppress the dissolution of long-chain polysulfide (Li2Sn, 4 ≤n≤ 8) species into electrolyte. To this end, we report a free-standing Al2O3–Li2S–graphene oxide sponge (GS) composite cathode, in which ultrathin Al2O3 films are preferentially coated on Li2S by an atomic layer deposition (ALD) technique. As a result, a combination of high electron conductivity (from GS) and strong binding with Li2Sn (from ultrathin Al2O3 films) was designed for cathodes. The newly developed Al2O3–Li2S–GS cathodes are able to deliver a highly reversible capacity of 736 mA h gLi2S−1 (427 mA h gcathode−1) at 0.2C, which is much higher than that of corresponding cathodes without Al2O3 (59%). Also, the long-term cycling stability of Al2O3–Li2S–GS cathodes was demonstrated up to 300 cycles at 0.5C with an excellent capacity retention of 88%. In addition, combined with density functional theory calculations, the promotional mechanism of ultrathin Al2O3 films was elucidated using extensive characterization. The ultra-thin Al2O3 film with optimal thickness not only acts as a physical barrier to Li2S nanoparticles, but provides a strong binding interaction to suppress Li2Sn species dissolution. [ABSTRACT FROM AUTHOR]