TiO 2 colloids are very useful photocatalytic systems, capable of converting solar energy to chemical or electrical energy and environmental cleaning. The key step in enhancing photocatalytic efficiency is improving photoinduced interfacial electron transfer like plant photosynthesis. It remains difficult to modify TiO 2 particles as a real analogue of the photosynthetic reaction centers of green plants. We attempted to incorporate a photoreactive heteropoly acid (HPA) such as H 3 PW 12 O 40 into TiO 2 colloids in aqueous polyvinyl alcohol (PVA) (0.1%) solution, and found that two light reactions appear to operate in a series. Upon illumination of the HPA/TiO 2 system with near-UV light (300-375 nm), interfacial electron transfer takes place from the conduction band of TiO 2 to the incorporated HPA, which is also excited to catalyze photoreduction of Methyl Orange. The extent of the photoinduced reduction of the HPA adsorbed on TiO 2 particles depends on the concentration ratio of the HPA and TiO 2 colloids, irradiation wavelength, and intensity of radiation. It is found that the interfacial electron-transfer mechanism of HPA/TiO 2 is quite analogous to the "Z-scheme" mechanism for plant photosynthetic systems. The photoinduced charge-carrier generation at the heterojunction is very efficient, and the photoreduction of Methyl Orange has been observed to be synergistically enhanced upon illumination of the HPA-incorporated TiO 2 with visible light as well as near-UV light.

A novel chimeric gene with a 5' end containing the nearly complete sequence of the coxI gene and a 3' end showing homology with chive orfA501 was isolated by genome walking from two cytoplasm types: CMS-S and CMS-T, both of which induce male-sterility in onion (Allium cepa L.). In addition, the normal active and variant inactive coxI genes were also isolated from onions containing the normal and CMS-S cytoplasms, respectively. The chimeric gene, designated as orf725, was nearly undetectable in normal cytoplasm, and the copy number of the normal coxI gene was significantly reduced in CMS-S cytoplasm. RT-PCR results showed that orf725 was not transcribed in normal cytoplasm. Meanwhile, the normal coxI gene, which is essential for normal mitochondrial function, was not expressed in CMS-S cytoplasm. However, both orf725 and coxI were transcribed in CMS-T cytoplasm. The expression of orf725, a putative male-sterility-inducing gene, was not affected by the presence of nuclear restorer-of-fertility gene(s) in male-fertility segregating populations originating from the cross between a male-sterile plant containing either CMS-T or CMS-S and a male-fertile plant whose genotypes of nuclear restorer gene(s) might be heterozygous. The specific stoichiometry of orf725 and coxI in the mtDNA of the three cytoplasm types was consistent among diverse germplasm. Therefore, a molecular marker based on the relative copy numbers of orf725 and coxI was designed for distinguishing among the three cytoplasm types by one simple PCR. The reliability and applicability of the molecular marker was shown by testing diverse onion germplasm.

Lasing action by planar-, fiber-, or ring-type waveguide has been extensively investigated with different types of microcavities such as thin films, wires, cylindrical tubes, or ribbons. However, the lasing action by sharp bending waveguide, which promises efficient interconnection of amplified light in the photonic circuits, remains unexplored. Here, we report the first observation of microcavity effects in the organic rectangular microtubes (RMTs) with sharp bends (ca. 90°) and subwavelength nanoscale wall thicknesses, based on single crystalline and themostable tetra(4-pyridyl)porphyrin (H(2)TPyP)-RMTs synthesized by the VCR process. A bright tip emission is observed from the sharp bending edges of a single RMT upon laser excitation, demonstrating a clear waveguiding behavior in RMT. The appearance of a peak from the (0-1) band at a threshold tube length and the gradual decrease of its full width at half-maximum (fwhm) suggest that amplification of spontaneous emission (ASE) is developed by stimulated emission along the walls of the RMTs. The ehancement of the ASE peak together with the narrowing of its fhwm over a threshold pump power and the tube size (width and length) dependence of the mode spacing strongly support vibronic lasing action in the RMTs. The stimulated emission by the subwavelength bending waveguide demonstrates that the organic RMTs can be applied as new building blocks for micromanipulation of optical path and amplification in the integrated circuits for efficient photonic devices.

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The effects of Rand β-cyclodextrins (CDs) on the twisted intramolecular charge transfer (TICT) emission of p-(N,N-diethylamino)benzoic acid (DEABA) in aqueous solution have been investigated by using steadystate and time-resolved fluorescence techniques. The ratio of the TICT emission to the normal emission increases as β-CD concentration increases, while it decreases significantly upon addition of R-CD. This behavior is in accordance with CD dependent decay times of the TICT and normal emissions, indicating the formation of different 1:1 DEABA/CD inclusion complexes. An increased pK a value of DEABA in the R-CD inclusion complex is determined relative to that of the β-CD complex. The rise time for the TICT emission increases as the β-CD concentration increases, whereas no rise time is observed in the case of the R-CD complex. These results and the size of the diethylamino group clearly suggest that the orientation of the DEABA in the β-CD complex is different from that in the R-CD complex; the carboxyl group of DEABA is encapsulated in the R-CD cavity, whereas it is exposed to the water phase in the β-CD complex. The CD dependences of the TICT fluorescence properties demonstrate that the specific hydrogen bonding between the carboxyl group and water plays an important role in the excited-state TICT. † Dedicated to Professor Pill-Soon Song for the occasion of his 60th birthday.

Two strains (Gsoil 492T and Gsoil 643T) isolated in Pocheon Province, South Korea, from soil used for ginseng cultivation were characterized using a polyphasic approach. Both isolates comprised Gram-negative, aerobic, non-motile, rod-shaped bacteria. They had similar chemotaxonomic characteristics, e.g. containing MK-7 as the major quinone, having a DNA G+C content in the range 42.5–43.3 mol% and possessing iso-C15 : 0 and iso-C17 : 0 3-OH as the major fatty acids. A phylogenetic analysis based on 16S rRNA gene sequences indicated that the two isolates formed a tight cluster with several uncultured bacterial clones and with the established genera Terrimonas, Niastella and Chitinophaga in the phylum Bacteroidetes but were clearly separate from these genera. The levels of 16S rRNA gene sequence similarity between the isolates and type strains of related genera ranged from 87.5 to 92.4 %. Furthermore, the results of physiological and biochemical tests allowed phenotypic differentiation of the isolates from phylogenetically closely related species with validly published names. The level of 16S rRNA gene sequence similarity between the two strains was 99.5 %, whereas the DNA–DNA relatedness value was 44 %, indicating that they represent separate species. On the basis of the polyphasic evidence, a novel genus, Flavisolibacter gen. nov., and two novel species, Flavisolibacter ginsengiterrae sp. nov. (type strain Gsoil 492T=KCTC 12656T=DSM 18136T) and Flavisolibacter ginsengisoli sp. nov. (type strain Gsoil 643T=KCTC 12657T=DSM 18119T), are proposed. Flavisolibacter ginsengiterrae is the type species of the genus.

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A male-sterile (MS) radish (Raphanus sativus L.) was found in an accession collected from Uzbekistan. Unlike Ogura MS radishes in which no pollen grain is typically visible during anthesis, a small number of pollen grains stuck together in the dehiscing anthers was observed in the newly identified MS radish. Fluorescein diacetate tests and scanning electron micrographs showed that pollen grains in the new MS radish were severely deformed and non-viable. Cytological examination of pollen development stages showed a clear difference in the defective stage from that seen in Ogura male-sterility. Reciprocal cross-pollination with diverse male-fertile lines indicated that pollen grains of the new MS radish were completely sterile, and the female organs were fully fertile. When the new MS radish and Ogura MS lines were cross-pollinated with a set of eight breeding lines, all F1 progeny originating from crosses with the new MS radish were male-sterile. In contrast, most of the F1 progeny resulting from crosses with Ogura MS lines were male-fertile. These results demonstrated that factors associated with induction of the newly identified male-sterility are different from those of Ogura male-sterility. The lack of restorer lines for the newly identified male-sterility led us to predict that it might be a complete cytoplasmic male-sterility without restorer-of-fertility genes in nuclear genomes. However, cross-pollination with more diverse radish germplasm identified one accession introduced from Russia that could completely restore fertility, proving the existence of restorer-of-fertility gene(s) for the new male-sterility. Meanwhile, the PCR amplification profile of molecular markers for the classification of radish mitochondrial genome types revealed that the new MS radish contained a novel mitotype.