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Membrane proteins play essential roles in the cell, and they constitute one of the most important targets of drugs. Studying membrane proteins in a controlled model membrane environment can provide unambiguous, quantitative information on their molecular properties and functions. However, reconstituting membrane proteins in a model system poses formidable technological challenges. Here, we developed a novel model membrane platform for highly sensitive observation of membrane proteins by combining a micropatterned lipid membrane and a nanofluidic channel. A micropatterned model membrane was generated by lithographically integrating a polymerized lipid bilayer and a natural (fluid) lipid bilayer. A nanofluidic channel having a defined thickness was formed between the fluid bilayer and a polydimethylsiloxane (PDMS) slab by attaching the polymeric bilayer and PDMS slab using an adhesion layer composed of silica nanoparticles that are coated with a biocompatible polymer brush. As we reconstituted rhodopsin (Rh), a G-protein-coupled receptor (GPCR), from a detergent-solubilized state into the fluid bilayer, only successfully reconstituted Rh molecules diffused laterally in the lipid bilayer and migrated into the nanogap junction, where they could be observed with a vastly improved signal-to-background ratio. The nanogap junction effectively separates the sites of reconstitution and observation and provides a novel platform for studying the molecular properties and functions of membrane proteins at the single-molecular level.

Disubstituted adamantanes having pyrogallol derivatives as V-shaped host molecules were synthesized to prepare complexes with carboranes, which are representative spherical guest molecules for macrocyclic compounds, including calixarenes and cyclotriveratrylenes. The crystallization of o-carborane (a) and 1,3-bis(3,4,5-trimethoxyphenyl)adamantane (1) in toluene resulted in the formation of inclusion crystals (1a) in a 1 : 1 ratio. X-ray crystallographic analysis revealed that two oxygen atoms in 1 interact with two hydrogen atoms of a through CH⋯O interactions to afford the complexes. In the case of 1,3-bis(3,4,5-triethoxyphenyl)adamantane (2), no inclusion crystal was obtained due to steric hindrance of the ethyl groups. Furthermore, the crystallization of 1 and a benzoquinone derivative (b) provided reddish crystals (1b) with a 1 : 2 host : guest complexation stoichiometry, where lone pair⋯π interactions in the complexes were observed in addition to donor–acceptor interactions.

Using different frequencies of 2.45 GHz and 915 MHz, the effect of excitation frequency on the spatial distributions of a surface wave plasma for 450 mm wafer processing was experimentally investigated at a medium pressure of 1 Torr. As a result, it was found that the mode number of standing waves which the surface waves form in the radial direction has great influence on the radial distribution of plasma density. Consequently, the plasma uniformity in the downstream region at 915 MHz was better than that at 2.45 GHz. On the other hand, the electron temperature was roughly constant and below 1.5 eV except in the vicinity of the quartz window at both frequencies.