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Abstract. The prevalence of virulent Rhodococcus equi in soil collected from 17 domestic animal farms (from 12 cattle, 1 pig, and 4 horse farms) and in 6 clinical specimens from patients with acquired immune deficiency syndrome (AIDS) in Chiang Mai, Thailand, was investigated. The isolates were tested for the presence of 15-17-kDa antigens (VapA) and a 20-kDa antigen (VapB) by immunoblotting and for the presence of virulence plasmid DNA. Rhodococcus equi was isolated from most soil samples (68 of 80) obtained from the 17 farms, with 2.0 ϫ 10 2 to 6.0 ϫ 10 5 colony-forming units per gram of soil. We detected VapA in none of the 537 isolates from the soil samples. In one isolate from a pig farm, both VapB and virulence plasmid DNA were detected. Of the 6 clinical isolates from patients with AIDS, however, 4 isolates contained both VapB and virulence plasmid DNA. The remaining 2 isolates were avirulent.

The degradation of model substances, benzaldehyde (C(6)H(5)CHO) and formaldehyde (HCHO), were investigated under various conditions, namely, ultrasound (US) irradiation, TiO(2) photocatalysis with UV irradiation (UV/TiO(2)), and the combination of sonophotocatalysis and UV irradiation (US/UV/TiO(2)), in order to clarify the synergistic effects between US and UV/TiO(2). US and UV/TiO(2) primarily contribute to the degradation of highly hydrophobic and hydrophilic substances, respectively. However, the degradation rate was found to depend on the chemical properties and concentration of not only the substances initially present, but also their decomposition intermediates. Here, the essential information for accurately evaluating the synergistic effects on reaction rate under US/UV/TiO(2) conditions is reported, with a focus on the behavior of decomposition intermediates.

ABSTRACT. The prevalence of virulent R. equi having 15-to 17-kDa antigens (VapA) in fecal isolates from 13 thoroughbred foals and their dams on 5 farms in Kagoshima, Japan, and the plasmid profiles of VapA-positive isolates by restriction fragment digestion patterns were investigated to compare the genotypic variation among virulence plasmids of R. equi isolates from Japan. In total, 218 (24.6%) of 886 isolates from the feces of the 13 foals and 13 (12.5%) of 104 isolates from the feces of their dams demonstrated VapA-positive R. equi. Plasmid DNA preparations of 231 virulent isolates from foals and dams were analyzed by restriction enzyme digestion with endonucleases EcoRI, EcoT22I and HindIII and were divided into 3 types: 172 isolates contained a 90-kb type I plasmid, 57 contained a 90-kb type III plasmid and 2 contained a 90-kb type IV plasmid. This study demonstrates a geographic character in the distribution of virulence plasmids found in VapA-positive isolates from thoroughbred foals in Kagoshima.

IntroductionThe construction of an artificial photosynthetic system is attracting a great deal of attention because of the potential to create fuels from solar visible-light energy and water. For this purpose photoinduced charge separation in an aqueous phase is of primary importance. Photochemical charge separations have been investigated using a Ru(bpy) 3 2þ sensitizer in aqueous solution, but these have been studied only in transient states or in the presence of sacrificial donors or acceptors. [1,2] Sensitization of a large band-gap TiO 2 photo anode, reported by Honda and Fujishima, [3] has also been one of the topics for photoinduced charge separation. The photosensitized solar cell composed of a nanoparticulate TiO 2 porous film and adsorbing dye reported by Grätzel's group [4] has shown a great success in the relevant research area. Substitution of this organic liquid by a solid-state electrolyte such as a polymer gel to stabilize the cell is one of the important research topics in this area. [5,6] On the other hand, the photochemical charge separation has only been possible in an organic medium with this sensitized solar cell. In an aqueous phase, the dye is detached from the TiO 2 surface, such that the cell does not show any stable characteristics. If sensitization is also possible in the water phase, it might lead to a widely interesting and important research area of water cleavage by solar irradiation.The present authors are interested in utilizing this sensitized TiO 2 as a photoinduced charge separation system in water, with the view to generating artificial photosynthesis to create fuels from solar energy and water in the future. Thus, the behavior of the cell in a water medium has been investigated. Rabani and Dai have reported the use of natural pigments from pomegranate adsorbed on a TiO 2 nanocrystalline film in an aqueous medium and obtained some good Communication: Solar cells comprised of nanoparticulate TiO 2 porous film photosensitized with an adsorbing dye have been utilized as photoinduced charge separation systems in aqueous media with the view to forming future artificial photosynthetic systems able to create fuels from solar energy and water. The photoinduced charge separation of the sensitized TiO 2 cell in a quasi-solid, made from agarose or k-carrageenan, was investigated.I-V curves under 98 mW Á cm À2 irradiation of ITO/TiO 2 / Ru(dcbpy) 2 (NCS) 2 . Electrolyte: 0.1 M LiI/0.01 M I 2 in a quasi-solid of 0.2 wt.-% gelatin containing a large excess of water.results. [7] However, the dye is a mixture of natural products so that its structure and activity are difficult to investigate. In addition, only the photocurrent value was given without the electrode area data, so that comparison with other data is difficult. We have reported that polysaccharides such as agarose (1) and k-carrageenan (2) can form a tight and elastic solid which contains excess water, and that electrochemical and photochemical reactions can take place in the solid the same as in pure water. [8] We have expected...