Isolation of short, tandem repeat sequences from mayfly Rhithrogena japonica Uéno 1928 has been carried out by probing the multicopy DNA regions using labeled total genomic DNA. Several microsatellites comprised of pyrimidine/purine-biased (Pyr/Pur) repeating units (CT, TCTG, and TCTCTG) and two minisatellites were identified. No locus containing (CA)_n repeat has been identified so far by screening with total genomic DNA and (CA)₂₅ probes. The Pur/Pyr microsatellites may be more abundant than (CA)_n microsatellite in the R. japonica genome. Both minisatellite sequences, termed Rja66 family (107bp repeating unit) and Taq I-family (repeating unit about 160bp), have self-complementary regions within the repeating units, thereby conforming to stem-loop structures in single-stranded DNA. As for microsatellite loci, a preliminary analysis on two microsatellites Rja18-1 (CT repeat, FJ827088) and Rja130F (TCTCTG repeat, FJ826512) was done for a local population of R. japonica, showing that they were highly polymorphic. Characterization of genetic structures of local R. japonica populations using Rja18-1 locus, demonstrated significant differences between geographically distant populations indicating an impaired genetic flow between such populations.

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High-temperature oxidation resistance of FeCrAl alloys with small amounts of yttrium was studied in oxygen-water vapor (47 vol%) up to five cycles (one cycle = 18ks) at 1573K, by mass gain measurements, the amount of spalled oxide, X-ray diffraction, scanning electron microscopy, and field emission-transmission electron microscopy-energy dispersive spectroscopy. Oxide films on FeCrAl, FeCrAl0.1Y and FeCrAl0.2Y alloys spalled, however, those of on FeCrAl0.5Y alloy showed good oxide adherence during cyclic oxidation. Oxides on all the alloys were mainly found as α-Al₂O₃, and oxides on the alloys with yttrium were α-Al₂O₃ and Y₃Al₅O₁₂. Oxide adherence of FeCrAl0.5Y alloy was mainly improved by the keying effect of Y₃Al₅O₁₂ pegs at the oxide⁄alloy interface.

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The goal of this study is to fabricate 3-dimensional living tissue utilizing our ink-jet technology. Our inkjet technology has two merits; those were high resolution to print and ability to eject highly viscous liquid. In this paper, collagen was used as a scaffold material of the cells. Alginate gel is used as supporting scaffolds. We developed basic technology to fabricate 3-dimensional living tissue.

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Dye-Sensitized Solar Cell (DSC) is highly focused by many researchers because DSC has good merits those are flexible and colorful. However, efficiency of DSC is low. Many researches on chemical characteristics and shape of titania and dye to improve efficiency are carried out. We applied electrostatic inkjet technology for patterning titania layer of DSC because fabrication process should be developed to contribute to high efficiency. New machine that can print titania is essential to fabricate DSC on various surface of flexible electronics. The optimized thickness of titania layer is changed when the titania and dye are changed of type. Traditionally, doctor blade method and screen print method has been used to fabricate titania layer. However, these methods are not suitable to optimize thickness of titania layer. In this paper, we developed the machine to print titania layer. We demonstrated that thickness of titania layer depends on printing time and efficiency is changed when thickness of titania layer is changed.

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Improvement of the decompression unit “Organic engine” that can generate kinetic energy from the chemical energy of chemicals such as glucose has been proposed and tested. The organic engine was fabricated by separating a cylindrical cell into a top-cell for gas-phase and a bottom-cell for liquid-phase, which separated by glucose oxidase immobilized membrane. Decompression was generated by catalysis of glucose oxidation. However, the concentration of glucose to actuate the system was 100 mmol⁄L that is too high compared to the human blood glucose concentration to apply it for artificial pancreas-like devices. In order to increase decompression rate, methods to enlarge area of the enzyme membrane per volume of the gas chamber were proposed and evaluated. Decompression rate in modified cell on 25 mmol⁄L glucose solution was equal to that of in conventional cell (-7.2 Pa･cm3⁄s) on 100 mmol⁄L glucose solution. As a result, three times higher output was enable to actuate on low glucose concentration close to blood sugar.

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The effects of temperature distribution and external vibration on stabilized supply flow rate of small bore journal sliding bearing were experimentally investigated. Journal sliding bearings are used widely in many rotational machineries such as engine, turbine, HDD etc.. However, journal sliding bearings generate oilwhip under high speed operation. In order to solve this problem, Hashimoto suggested a stabilization method for suppressing oilwhip by using starved lubrication in which supply oil rate is reduced. However, the starved lubrication have the risks of sudden rising of temperature and regenerating oilwhip caused by external vibrations. In this study, the temperature distribution around the axis and the effect of the external vibrations was investigated to make clear the behaivior of the oil. The temperature distributions were measured with thermocouples and cavitations generating in the bearing clearance were visualized by using a high-speed camera. In addition, the vibration test was carried out with an impulse hammer and an acceleration sensor. The area was observe for the temperature to increase rapidly from the results of reducing supply of flow rate. In addition, in the case of increasing supply frow rate, the difference between the maximum temperature and minimum temperature in the bearing is reduced gradually. Moreover, the oil whip was occurred by the external vibration. It was found that both risks were possible to avoid by adjusting the supply flow rate adequately.

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This paper summarizes the transition of energy policy of Japan with detailed data. Discussions are made on the Japan’s nuclear policy and future trend in energy policy and technology based on actual research and development of energy technology. Particular attention is given to the fact that many complicated technological, social and political factors are involved and connected each other in considering energy security and policy making. As conlcuding remarks, it is pointed out that human security as well as energy security should be strictly considered in the energy ploicy making for sustainable human society and our future generations.

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