Considering the high level of sensitivity of our proposed sonographic classification, fine-needle aspiration biopsy should be performed on thyroid nodules classified as positive, regardless of palpability.

Current hyaluronic acid (HA) hydrogel systems often cause cytotoxicity to encapsulated cells and lack the adhesive property required for effective localization of transplanted cells in vivo. In addition, the injection of hydrogel into certain organs (e.g., liver, heart) induces tissue damage and hemorrhage. In this study, we describe a bioinspired, tissue‐adhesive hydrogel that overcomes the limitations of current HA hydrogels through its improved biocompatibility and potential for minimally invasive cell transplantation. HA functionalized with an adhesive catecholamine motif of mussel foot protein forms HA‐catechol (HA‐CA) hydrogel via oxidative crosslinking. HA‐CA hydrogel increases viability, reduces apoptosis, and enhances the function of two types of cells (human adipose‐derived stem cells and hepatocytes) compared with a typical HA hydrogel crosslinked by photopolymerization. Due to the strong tissue adhesiveness of the HA‐CA hydrogel, cells are easily and efficiently transplanted onto various tissues (e.g., liver and heart) without the need for injection. Stem cell therapy using the HA‐CA hydrogel increases angiogenesis in vivo, leading to improved treatment of ischemic diseases. HA‐CA hydrogel also improved hepatic functions of transplanted hepatocytes in vivo. Thus, this bioinspired, tissue‐adhesive HA hydrogel can enhance the efficacy of minimally invasive cell therapy.

We developed an efficient computation scheme for the phase-field simulation of grain growth, which allows unlimited number of the orientation variables and high computational efficiency independent of them. Large-scale phase-field simulations of the ideal grain growth in two-dimensions (2D) and three-dimensions (3D) were carried out with holding the coalescence-free condition, where a few tens of thousands grains evolved into a few thousand grains. By checking the validity of the von Neumann-Mullins law for individual grains, it could be shown that the present simulations were correctly carried out under the conditions of the ideal grain growth. The steady-state grain size distribution in 2D appeared as a symmetrical shape with a plateau slightly inclined to the small grain side, which was quite different from the Hillert 2D distribution. The existence of the plateau stems from the wide separation of the peaks in the size distributions of the grains with five, six, and seven sides. The steady-state grain size distribution in 3D simulation of the ideal grain growth appeared to be very close to the Hillert 3D distribution, independent of the initial average grain size and size distribution. The mean-field assumption, the Lifshitz-Slyozov stability condition, and all resulting predictions in the Hillert 3D theory were in excellent agreement with the present 3D simulation. Thus the Hillert theory can be regarded as an accurate description for the 3D ideal grain growth. The dependence of the growth rate in 3D simulations on the grain topology were discussed. The large-scale phase-field simulation confirms the 3D growth law obtained from the Surface Evolver simulations in smaller scales.