Visible-light-transparent p-type NiO films were deposited by reactive RF sputtering under unintentional heating. An optical transmittance of >80% was obtained in the wavelength range of 500–800 nm when the films were deposited under a very low O2 fraction in the gas phase O2/(Ar+ O2) = 0.5%. This result may reflect a decrease in the concentration of Ni vacancies due to the increase in their formation energy under oxygen-poor deposition conditions. Heterostructure pn junctions consisting of p-type NiO and n-type ZnO layers were also deposited. We eventually observed a slight but noticeable photovoltaic effect.

A novel functionally PEGylated quantum dot (QD) was prepared by a coprecipitation method in the presence of the biotin-PEG/polyamine block copolymer. When CdCl2 and Na2S were mixed in aqueous media in the presence of the biotin-PEG-b-poly(2-(N,N-dimethylamino)ethyl methacrylate) [biotin-PEG/PAMA], a CdS QD with a size of ca. 5 nm was prepared. The polyamine segment was anchored on the surface of the formed CdS nanoparticle, whereas the PEG segment was tethered on the surface to form a hydrophilic palisade, thus improving the dispersion stability in aqueous media even under a high salt concentration condition. An effective fluorescent resonance energy transfer (FRET) was observed by the specific interaction of the biotin-PEG/PAMA stabilized CdS QD with TexasRed-labeled streptavidin of the physiological ionic strength of 0.15 M. The extent of the energy transfer was in proportion to the concentration of the TexasRed-streptavidin. This FRET system using the PEGylated CdS QD coupled with fluorescent-labeled protein can be utilized as a highly sensitive bioanalytical system.

This study retrospectively analyzed the clinical outcomes of endoscopic resection of 26 sporadic (i. e., not associated with polyposis syndrome) nonampullary duodenal lesions representing high-grade dysplasia or intramucosal carcinoma (duodenal HGD/IMC) in 23 patients. No severe complications such as perforation were observed, but three cases of delayed bleeding were seen. The use of endoscopic clips significantly decreased the delayed bleeding rate (0/19, 0%) compared with cases in which clips were not used (3/7, 42.9%; P = 0.013, χ2 test). Eighteen lesions (69.2%) were removed by en bloc resection. The follow-up period after resection was 25.5 ± 23.3 months. Two lesions (7.7%) that recurred locally were detected at the first surveillance endoscopy 3 months after resection. These lesions were 22 and 15 mm in size respectively and were resected piecemeal. Endoscopic resection is an effective and safe procedure for treating duodenal HGD/IMC. En bloc resection and prophylactic clip usage are encouraged.

Magnetic and structural phase diagram in a spinel-type solid solution system Fe(1-x)Mn(x)Cr(2)O(4) has been investigated. The cubic-to-tetragonal transition temperature T(s 1) is gradually reduced by the substitution of Mn(2+) (3d(5)) for Jahn-Teller-active Fe(2+) (3d(6)) ions, implying the long-range nature of the ferroic interaction between orbitals. In the paramagnetic tetragonal phase for x < 0.5, the c parameter is shorter than a because of the anharmonicity of the elastic energy. The crystal structure further changes to orthorhombic at around the ferrimagnetic transition temperature T(N 1). T(s 1) and T(N 1) meet at x = 0.5, and Mn substitution of more than 0.5 gives rise to another tetragonal phase with a < c. The systematic change in crystal structure is discussed in terms of competition between the anharmonic lattice potential and the intra-atomic spin-orbit interaction at Fe(2+).

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The preparation and compatibilizing ability of heteroarm star-shaped block copolymers (6 and 8) composed of polystyrene and nylon 6 units diverged from the phosphazene core were investigated. The heteroarm star-shaped copolymers were prepared by a partial coupling reaction of the acid chloride of hexakis(4-carboxyphenoxy)cyclotriphosphazene [4, (4-ClCOC6H4O)6N3P3] with polystyrene having a terminal amino group (PSt−NH2) or poly(styryllithium), followed by the ring-opening polymerization of ε-caprolactam (ε-CL) with the residual carboxyl group in the phosphazene core. The coupling reaction of telechelic PSt−NH2 and poly(styryllthium) with 4 occurs smoothly to give carboxyphenoxycyclotriphosphazenes carrying 2.2−4.7 polystyrene chains, 5 and 7, respectively. The polymerization of ε-CL with hexakis(4-carboxyphenoxy)cyclotriphosphazene [2, (4-HOOCC6H4O)6N3P3] showed that all carboxyl groups participate in the initiation of polymerization to give hexaarmed star-shaped polymers. This implies that the residual carboxyl groups in 5 and 7 could also initiate the polymerization of ε-CL. The molecular weights of copolymers obtained from the polymerization of ε-CL with 5 and 7 are in agreement with those of calculated values, suggesting the formation of heteroarm star-shaped block copolymers with phosphazene core (6 and 8). When these copolymers were used as a compatibilizer of an immiscible blend, poly(2,6-dimethylphenylene oxide) (PPO) and nylon 6, DSC profiles showed a single transition temperature that shifted to lower temperature from the T g of PPO. The SEM photograph indicates that PPO disperses regularly and finely with 0.3 μm size in the nylon domain. Furthermore, the tensile strength and elongation at break of ternary blends increased with increasing the copolymer content. These results indicate that the effective penetration of each block sequence of the heteroarm star-shaped copolymers into the blend components is operative, that is, these copolymers act as an excellent compatibilizer for PPO/nylon 6 blends.