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Genetic analysis of single-cells is widely recognized as a powerful tool for understanding cellular heterogeneity and obtaining genetic information from rare populations. Recently, many kinds of single-cell isolation systems have been developed to facilitate single-cell genetic analysis. However, these systems mainly target non-adherent cells or cells in a cell suspension. Thus, it is still challenging to isolate single-adherent cells of interest from a culture dish using a microscope. We had previously developed a single-cell isolation technique termed "gel-based cell manipulation" (GCM). In GCM, single-cells could be visualized by photopolymerizable-hydrogel encapsulation that made it easier to isolate the single-cells. In this study, GCM-based isolation of single-adherent cancer cells from a culture dish was demonstrated. Single-adherent cells were encapsulated in a photopolymerizable hydrogel using a microscope and isolated with high efficiency. Furthermore, whole genome amplification and sequencing for the isolated single-adherent cell could be achieved. We propose that the GCM-based approach demonstrated in this study has the potential for efficient analysis of single-adherent cells at the genetic level.

Nanostructured amorphous silica in rice plants (biosilica or plant opal) plays an important role in plant growth related to food production. However, the same silica has a structural supporting role as well that has not been uncovered. The current study focuses on the structural design of the two main types of biosilicas in rice plants for the improvement of their mechanical properties. One structural motif is plate-like silicas, which cover most of the surfaces of leaf blades. Another is fan-shaped silicas, which are aligned inside leaf blades, providing a stiff backbone. These biosilica structures consist of 10–100 nm diameter nanoparticles. The mechanical properties, such as hardness and Young's modulus, of the biosilicas are associated with their relative density. Thus, the rice plant mechanics is inferred to be designed by changing the packing of the nanoparticles. Silica plates consisting of loosely packed particles have relatively low density and high flexibility enabling coverage of leaf blade surfaces, while fan-shaped silicas, which consist of tightly packed nanoparticles, are rigid to support the leaf blades as a backbone.

Uniform TiO2 nanospheres from hollow, core–shell and mesoporous structures have been synthesized using quasi-nano-sized carbonaceous spheres as templates. The TiO2 nanospheres formed after calcination at 400 °C are composed of ∼7 nm nanoparticles and the shells of the hollow TiO2 nanospheres are as thin as a single layer of nanoparticles. The ultrafine nanoparticles endow the hollow and mesoporous TiO2 nanospheres with short lithium ion diffusion paths leading to high discharge specific capacities of 211.9 and 196.0 mA h g−1 at a current rate of 1 C (167.5 mA g−1) after 100 cycles, and especially superior discharge specific capacities of 125.9 and 113.4 mA h g−1 at a high current rate of up to 20 C. The hollow and mesoporous TiO2 nanospheres also show superior cycling stability with long-term discharge capacities of 103.0 and 110.2 mA h g−1, respectively, even after 3000 cycles at a current rate of 20 C.