-During the characterization of hemorrhagic factor in venom of Rhabdophis tigrinus tigrinus, so-called Yamakagashi in Japan, one of the Colubridae family, a novel metalloproteinase with molecular weight of 38 kDa in the Duvernoy's gland of Yamakagashi was identified by gelatin zymography and by monitoring its proteolytic activity using a fluorescence peptide substrate, MOCAc-PLGLA 2 pr(Dnp)AR-NH 2 , which was developed for measuring the well-known matrix metalloproteinase (MMP) activity.After purification by gel filtration HPLC and/or column switch HPLC system consisting of an affinity column, which was immobilized with a synthetic BS-10 peptide (MQKPRCGVPD) originating from propeptide domain of MMP-7 and a reversed-phase column, the N-terminal amino acid sequence of the 38 kDa metalloproteinase was identified as FNTFPGDLK which shared a high homology to Xenopus MMP-9.The 38 kDa metalloproteinase required Zn 2+ and Ca 2+ ions for its proteolytic activity. In addition, the proteolytic activity was almost completely inhibited by BS-10, a MMP inhibitor, but not by the serine proteinase inhibitors, cysteine proteinase inhibitors and aspartic proteinase inhibitors.Together these results demonstrated that the 38 kDa proteinase is a novel snake verom metalloproteinase (SVMP) containing HExGHxxGxxH motif which possesses high affinity to the BS-10 peptide, into its molecule, and the enzymatic properties are closed to that of MMPs.Based on the results obtained in the present study, we concluded that the 38 kDa metalloproteinase is a novel metalloproteinase whose activity may be regulated by the cysteine switch mechanism, and could be classified as one of the matrix metalloproteinases rather than snake venom metalloproteinases.

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The prototype sodium-cooled FBR MONJU was shut down due to a sodium leak incident on Dec. 8, 1995, and has remained shut-down since. Currently, a safety assessment of the proposed new countermeasures against future leaks is being carried out. One of these countermeasures, a new sodium leak monitoring system to detect small scale leakage with high reliability, will be installed throughout the entire secondary cooling circuit area. An initial assessment suggested that smoke sensors would best meet the requirements for this monitoring system from the standpoints of sensitivity, reliability, and installation cost. To confirm the suitability of smoke sensors for sodium leak monitoring, their sensitivity to sodium aerosol has been measured experimentally, and their ability to detect small scale sodium leakage has been estimated by analytical methods.

We present adaptive learning control algorithms which use Markov parameters. Since in the algorithm, the control input and the model parameter are updated at each iteration, it is applicable to unknown systems in a class. In order to overcome the effect of a disturbance, Markov parameters of the inverse model is also introduced. The effectiveness of the algorithm is illustrated by means of a numerical simulation and experimental application to an active vibration isolation system.