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There are critical issues in siRNA therapeutics, as follows, 1) siRNA is immediately degraded in extracellular milieu, such as bloodstream, 2) the size of siRNA is -5nm, so siRNA is readily excreted from the kidney to the urine, and 3) the negative charge of siRNA repels the negatively charged cell membrane, inhibiting the cellular uptake of siRNA. Thus, many previous studies have encapsulated siRNA into -100 nm-sized nanoparticles to stabilize it. However, refractory cancers have tight barriers that prevent the penetration of such nanoparticles into cancer cells. To overcome these hurdles, a new type of siRNA nanocarrier is developed for the cancer-targeted siRNA delivery, using a Y-shaped block catiomer (YBC) with precisely regulated chain length and precisely neutralize their charges. Indeed, two YBCs are bound to a single siRNA in the bloodstream, generating a dynamic polyin-pair, termed uPIC. Owing to both high stability in the bloodstream and ultra-small (or optimal) size (-18 nm) to penetrate fibrotic tissues, uPIC efficiently delivers siRNA into murine models of fibrotic pancreatic cancer and glioblastoma, exerting the significant anticancer activity in vivo.

The macroscale mechanical properties of dissimilar joints are generally influenced by the fracture behavior of joint interface. However, little is known about the dominant factor for the joint properties related with both macroscale fracture behavior and microscale interfacial properties. Herein, microscale tensile testing of the joint interface was coupled with the macroscale fracture evaluation to elucidate the dominant factor of strength in dissimilar joints between 6061 aluminum alloy and high tensile strength galvannealed steel via friction stir spot welding (FSSW). Microstructural analyses revealed the characteristic formation of interfacial microstructure accompanied by friction and Zn discharge during the FSSW process. Microscale tensile testing was performed on the specimen on which the pre-notch was introduced to induce local fracture at the intended position on the joint interface. Results showed the presence of the weakest interface attributed to initial joining defects formed by Zn concentration at the outer area, which were consistent with the outside of the crack arresting area confirmed by macroscale evaluation. These results indicated that the joint strength of dissimilar joints between 6061 aluminum alloy and galvannealed steel is dominated by the local strength of the joining area without defects and suggested a process design for improving dissimilar joints.

We developed an autonomous human-like guide robot for a science museum. Its identifies individuals, estimates the exhibits at which visitors are looking, and proactively approaches them to provide explanations with gaze autonomously, using our new approach called speak-and-retreat interaction. The robot also performs such relation-building behaviors as greeting visitors by their names and expressing a friendlier attitude to repeat visitors. We conducted a field study in a science museum at which our system basically operated autonomously and the visitors responded quite positively. First-time visitors on average interacted with the robot for about 9 min, and 94.74% expressed a desire to interact with it again in the future. Repeat visitors noticed its relation-building capability and perceived a closer relationship with it.

Convenient methods with simple devices comprised of an opticalcell and prisms were proposed for the direct spectrophotometric measurement of adsorbed species at liquid-liquidinterface, using a protonated meso-tetraphenylporphyrinin an aggregate form as an interfacial adsorbate. The spectrum of the aggregate within the visible wavelength region was effectively observed by three kinds of prism-cell assembly for (1) the double-phase transmission method, (2) the multiple attenuated total-internal reflection method and (3) the external reflection method. Characteristics of spectral appearance in each of the methods were described and discussed.