A REACTION-EXTRACTION-REGENERATION SYSTEM FOR HIGHLY SELECTIVE OXIDATION OF BENZENE TO PHENOL

The reaction-extraction-regeneration system for the liquid-phase oxidation of benzene to phenol in the benzene-water-oxygen system was investigated. Phenol was extracted in the extractor to reduce the concentration of phenol in the benzene phase. As vanadium catalyst was oxidized to inactive species after the oxidation reaction, the regenerator was installed in the system to reduce the oxidation state of vanadium catalyst from V⁴⁺ or VO²⁺ to the active V³⁺ under H₂ flow. The effects of various operating parameters including concentration of VCl₃ catalyst, O₂ and H₂ flow rates, benzene bubble size, pH, surface area of Pt regeneration catalyst, the metal species, and amount of ascorbic acid were investigated. Ascorbic acid was employed as a reducing agent for helping reduce the V⁴⁺ form to the active form and therefore improving the activity of vanadium catalyst. VCl₃ catalyst concentration of 10 mol/m³ with pH of 3–4 in the reactor and Pt surface area of 0.05 m² in the regenerator showed optimal conditions for the system.     

Properties of soya milk and tofu prepared with γ-irradiated soya beans

Soya beans (Glycine max) ‘hwang keum’ were γ-irradiated at dose levels of 0, 2.5, 5, 10 and 20 kGy and the effects of the irradiated soya beans on soya milk and tofu properties were studied. An irradiation dose of 5 kGy caused an increase in yield of soya milk and tofu while having very little effect on their quality. The properties of tofu prepared with the soya beans irradiated at 2.5–5 kGy showed no significant difference from the non-irradiated control. However, at higher doses (10–20 kGy), decreases in yield, water holding capacity and sag value of tofu were observed. Compared with the non-irradiated control, hardness and fracturability in the texture of tofu were both significantly increased when the soya bean had been irradiated at 10–20 kGy, while cohesiveness and adhesiveness decreased. The changes in color values of soya milk and tofu were pronounced at 20 kGy.     

The state of the art of nanobioscience in Japan

This paper reviews a part of the state of the art of nanobioscience in Japan. The importance of combination and integration of interdisciplinary principles is emphasized for the development of nanobioscience. Biomagnetics, biomechanics, nanomachining, self-replicating cell model, neuronal network, drug delivery system, and tissue engineering are discussed.     

Ensemble Stimulation of Embryoid Bodies using Substrate-Embedded Electrodes

Precise control of differentiation processes of pluripotent stem cells is essential for regeneration medicine, and electrical stimulation is one of the promising techniques, particularly for the regulation of neuronal regeneration. In the present study, we developed substrates with embedded electrodes, which allowed ensemble electrical stimulation of embryoid bodies (EBs). Microcavity-array patterns were fabricated on substrates with embedded electrodes. Uniform-size EBs of P19 cells were prepared, inserted one by one in each microcavity, and electrical stimulation was applied through substrate electrodes. Stimulus-induced intracellular calcium transients were successfully monitored by fluorescence imaging. The results suggested that this method would be useful for applying precisely controlled electrical stimulation to a large number of EBs of stem cells. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Regional trend and tissue distribution of brominated flame retardants and persistent organochlorines in raccoon dogs (Nyctereutes procyonoides) from Japan

The present study investigated concentrations and patterns of brominated flame retardants, such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs), and persistent organochlorines (OCs) in liver and adipose tissues of raccoon dogs (RD: Nyctereutes procyonoides) collected from two metropolises and a local prefecture in Japan during 2001-2006. Relatively high concentrations of PBDEs were found in RD livers, while HBCD levels were the lowest among the measured organohalogen compounds. Among PBDE congeners, BDE 209 was predominant in RDs from all the regions, indicating that pollution derived from the technical decaBDE product is extensive across Japan. On the other hand, concentrations of tetra- to nona-BDE congeners in RDs from a metropolis were significantly higher than those from the other two regions, implying that there were regional differences in the past usage of the technical tetraBDE and octaBDE products. Such a regional difference was also observed for HBCD levels. Lipid-normalized concentration ratios of liver to adipose tissue (L/A ratio) for tri to hepta-BDE congeners were lower than 1.0 in the investigated eight RDs, suggesting lipid-dependent accumulation. However, the LA ratios of BDE 209 exceeded 1.0 in all the specimens, suggesting hepatic retention of this compound. In addition, lipid-dependent accumulation of a-HBCD was observed, but the L/A ratios of gamma-HBCD were greater than 1.0 in some specimens. These results indicate that Japanese RDs have been recently exposed to BDE 209 and gamma-HBCD and accumulated both these compounds preferentially in blood-rich organs, probably due to their binding to proteins and/or rapid biotransformation, as reported in experimental rodents.     

Time trends and transplacental transfer of perfluorinated compounds in melon-headed whales stranded along the Japanese coast in 1982, 2001/2002, and 2006

As a result of the phase-out of production of perfluorooctanesulfonyl-based compounds by a major producer, concentrations of perfluorooctanesulfonate (PFOS) in marine mammals from North American and European coastal waters have been declining since the early 2000s. Nevertheless, temporal trends in perfluorochemical (PFC) concentrations in marine mammals from Asian coastal waters have not been examined. In this study, PFCs were determined in livers of melon-headed whales (Peponocephala electra) collected along the coast of Japan, from three mass strandings that occurred during the past 25 years. Concentrations of nine PFCs were determined in livers of 48 melon-headed whales that were collected during strandings in 1982, 2001/2002, and 2006. In addition, concentrations in liver tissues obtained from two pregnant females and their fetuses were compared for determination of transplacental transfer rates of PFCs during gestation. PFOS and perfluorooctanesulfonamide (PFOSA) were the predominant PFCs found in livers of melon-headed whales collected in 1982 (n = 22). PFOS, PFOSA, perfluoroundecanoate (PFUnDA), perfluorododecanoate (PFDoDA), perfluorodecanoate (PFDA), and perfluorononanoate (PFNA) were found in whales collected in 2001/2002 (n = 21) and in 2006 (n = 5). Concentrations of PFOS and PFOSA were approximately 10-fold higher in 2001/2002 than in 1982. Whereas concentrations of PFOSA then declined by 2-fold from 2001/ 2002 to 2006, concentrations of PFOS and perfluorocarboxylates did not decline after 2001/2002. Conversely, concentrations of PFNA and PFDA increased significantly from 2001/2002 to 2006. The proportion of perfluoroalkylsulfonates in total PFC concentrations decreased from 75% in 1982 to 51% in 2006. Conversely, the contribution of perfluorocarboxylates to total PFC concentrations increased from 25% in 1982 to 49% in 2006. PFUnDA was the major perfluorocarboxylate found in whale livers collected after 2000. Analysis of paired samples of mother-fetus demonstrated that the transplacental transfer rates of PFCs were higher than those for PCBs and PBDEs.     

Optimal authentication systems and combinatorial designs

In 1982, G.J. Simmons introduced a mathematical model of authentication theory. Recently, E.F. Brickell (1984) and D.R. Stinson (1988) have shown some combinatorial constructions for optimal authentication systems. In the present work, game-theoretical models are proposed for authentication systems that have multilevel costs on sources, and lower bounds of the game values are obtained. Some constructions of the optimal authentication systems that attain the bounds are shown     

A novel immunostimulating aspect of Lactobacillus gasseri: induction of "Gasserokine" as chemoattractants for macrophages

The chemotactic activity of the culture supernatants from 14 strains of Lactobacillus acidophilus and L. gasseri was examined for murine macrophages. Significant macrophage chemotactic activity was observed in three strains of L. acidophilus and all strains of L. gasseri. The highest activity was observed in the supernatant (1131-sup) from 24-h cultures of L. gasseri JCM1131T. The chemotactic factor from 1131-sup, designated as "Gasserokine", was purified by the C18 reverse phase and ion-exchange chromatography. The purity of Gasserokine was checked by HPLC with the reverse-phase mode. The chemotactic activity of Gasserokine was also observed for human monocytes. The macrophage chemotaxis induced by L. gasseri JCM1131T culture supernatants was discovered to be a new biological function exerted by probiotic lactic acid bacteria. Therefore, the activity is expected to be used for one of the functional parameters in the immunomodulating properties of probiotic lactic acid bacteria.     

Efficient use of an improved radiative transfer code to simulate near-global distributions of satellite-measured radiances

Two new extension modules that give the water-leaving radiance from the ocean and the snow bidirectional reflectance distribution function were implemented in the latest radiative transfer code. In addition, to simulate the near-global distributions of satellite-measured radiances by using the improved radiative transfer code, we tested and applied the look-up table method together with the process-separation technique of the radiative transfer calculation. The computing time was reduced from 1 year to 20 s to simulate one channel, one scene of the Global Imager image by use of an Alpha 21164A-2 (600-MHz) machine. The error analyses showed that the radiances were simulated with less than 1% error for the nonabsorbing visible channels and approximately 2% error for absorbing channels by use of this method.