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Alkenes and aromatics significantly contribute to the photochemical reactions in the Kanto Region, where the level of ozone frequently exceeds the level for photochemical smog warnings in summer. The major aromatic sources have been cataloged in the Pollutant Release and Transfer Register (PRTR) database in Japan; however, the major alkene sources are not included. We investigated the hourly variations in the volatile organic compound (VOC) concentrations at four sampling sites in the Tokyo Bay coastal area, which has a variety of VOC sources, including the petrochemical industry, chemical facilities, iron–steel plants, and refineries. The 116-component VOC data were used to conduct a positive matrix factorization (PMF) analysis to apportion the VOC sources; then, the source regions were estimated by combining the concentration ratios of the factors with the wind direction data. We used the hourly VOC data for the PMF analysis because alkenes are short-lived. Six factors were estimated using the PMF method and identified as liquefied petroleum gas + industry, aged air mass, fuel evaporation, petrochemical industry, aromatics, and solvent usage. The mean contribution ratios of these six factors were 8.9%, 19.9%, 9.3%, 10.4%, 9.9%, and 14.0%, respectively, whereas the mean contribution ratio of the residual was 27.7%. By combining the alkene concentration and factor contribution ratios with the wind direction, the petrochemical industry in the Kawasaki coastal area was demonstrated to be the main alkene source. In addition, the petrochemical industry makes the largest contribution to ozone production according to the OH radical loss rates of the six factors.

In order to simulate drifting and run-up ice floes driven by tsunamis, we developed a quasi-3D Discrete Element Method (DEM) in which phenomena unique to granular solids, such as the arch action, jam and pile up of such solids, can be simulated with a small computation load. The validity of the simulation method was verified by hydraulic experiments using synthetic ice. Some numerical simulations of drifting and run-up ice floes driven by a tsunami were performed to investigate the fundamental characteristics of ice run-up and the applicability to actual seas. It was confirmed that the simulation results could estimate risk areas where ice pile up and jam form as well as hazardous areas showing the degree of damage to buildings. Such calculation was expected to be useful for the compilation of hazard maps and the development of disaster mitigation plans in the future.

Ecl1 family genes (ecl1 (+), ecl2 (+), and ecl3 (+)) have been identified as extenders of the chronological lifespan in Schizosaccharomyces pombe. Here, we found that the triple-deletion mutant (∆ecl1/2/3) had a defect in sexual development after entry into the stationary phase, although the mutant essentially showed normal mating and sporulation under nitrogen starvation or carbon limitation. In this study, we showed that limitation of zinc or iron can be a signal for sexual development of S. pombe cells grown in Edinburgh minimal medium until the stationary phase and that Ecl1 family genes are important for this process. Because the ∆ecl1/2/3 mutant diminishes the zinc depletion-dependent gene expression, Ecl1 family proteins may function as zinc sensors in the process of sexual development.

Equine cells are required for isolation of viruses that infect the horse. However, only a few equine cell lines and cell cultures are available so far. Fetal horse kidney (FHK)-Tcl3.1 cell is a novel cell line established by introducing simian virus 40 (SV40) large T antigen. In the present study, the ability to propagate equine viruses was compared between FHK-Tcl3.1 cells and other equine cells. FHK-Tcl3.1 cells efficiently increased many viruses derived from or having pathogenicity to horses and produced high infective titers in culture fluids. These results indicate that FHK-Tcl3.1 cells would be useful for propagation and serological tests of viruses that affect Equidae.

Equine cells are required for isolation of viruses that infect the horse. However, only a few equine cell lines and cell cultures are available so far. Fetal horse kidney (FHK)-Tcl3.1 cell is a novel cell line established by introducing simian virus 40 (SV40) large T antigen. In the present study, the ability to propagate equine viruses was compared between FHK-Tcl3.1 cells and other equine cells. FHK-Tcl3.1 cells efficiently increased many viruses derived from or having pathogenicity to horses and produced high infective titers in culture fluids. These results indicate that FHK-Tcl3.1 cells would be useful for propagation and serological tests of viruses that affect Equidae.