We have clarified, for the first time, the spatiotemporal patterns of intracellular Ca(2+) increases at fertilization and the Ca(2+)-mobilizing mechanisms in eggs of hydrozoan jellyfish, which belong to the evolutionarily old diploblastic phylum, Cnidaria. An initial Ca(2+) increase just after fertilization took the form of a Ca(2+) wave starting from one cortical region of the egg and propagating to its antipode in all of four hydrozoan species tested: Cytaeis uchidae, Cladonema pacificum, Clytia sp., and Gonionema vertens. The initiation site of the Ca(2+) wave was restricted to the animal pole, which is known to be the only area of sperm-egg fusion in hydrozoan eggs, and the wave propagating velocity was estimated to be 4.2-5.9 mum/s. After a Ca(2+) peak had been attained by the initial Ca(2+) wave, the elevated Ca(2+) gradually declined and returned nearly to the resting value at 7-10 min following fertilization. Injection of inositol 1,4,5-trisphosphate (IP(3)), an agonist of IP(3) receptors (IP(3)R), was highly effective in inducing a Ca(2+) increase in unfertilized eggs; IP(3) at a final intracellular concentration of 12-60 nM produced a fully propagating Ca(2+) wave equivalent to that observed at fertilization. In contrast, a higher concentration of cyclic ADP-ribose (cADPR), an agonist of ryanodine receptors (RyR), only generated a localized Ca(2+) increase that did not propagate in the egg. In addition, caffeine, another stimulator of RyR, was completely without effect. Sperm-induced Ca(2+) increases in Gonionema eggs were severely affected by preinjection of heparin, an inhibitor of Ca(2+) release from IP(3)R. These results strongly suggest that there is a well-developed IP(3)R-, but not RyR-mediated Ca(2+) release mechanism in hydrozoan eggs and that the former system primarily functions at fertilization. Our present data also demonstrate that the spatial characteristics and mechanisms of Ca(2+) increases at fertilization in hydrozoan eggs resemble those reported in higher triploblastic animals.

A rapid enzyme immunoassay (EIA) for cocaine and its main metabolite, benzoylecgonine (BZE), using glucose oxidase (GOD) was established. Drug concentrations in samples were determined by the inhibition test. BZE-conjugated GOD and samples were added into the wells of a 96-well microtest plate coated with anti-BZE monoclonal antibody. After washings, color development was performed by additions of glucose, horse radish peroxidase (HRP) and 3,3′,5,5′-tetramethylbenzidine (TMB), which was a non-mutagenic and non-carcinogenic chromogen. The time required for the immune reaction and the subsequent color development was only 12 min in this EIA. The EIA specifically detected cocaine and BZE at the low detection limit, that is, about 45.4 pg/well for cocaine, and 433 pg/well for BZE, respectively. The values were hardly interfered by urine diluted to 10%. The present assay method was rapid, sensitive, simple, and safe, and was easily carried out anyplace a micro-plate reader was available. Therefore, it might be suitable to screen cocaine and BZE in urine at the scene of abuse.

Dynamic behavior of cathode ray tube (CRT) under the ball impact test condition was analyzed by computer simulation. Experiments were also carried out by using an instrumented drop-weight impact testing machine to investigate the impact load and stresses of CRT, and the phenomena of impact fracture of CRT were discussed. The following results were derived.(1) Dynamic behavior of CRT under several impact load conditions changing the impact speed and the hitting point was clarified by using the instrumented testing machine.(2) The results of computer simulation with the impact analysis program DYNA3D showed good agreement with the experimental dynamic behavior of CRT.(3) Static load due to vacuum in the tube or tightening force by the tension band had no effct on the dynamic characteristics of CRT before breaking.(4) It was explained quantitatively that hitting the corner of panel face at the impact test was more severe to the dynamic strength of CRT than the hitting the center of panel face.(5) The macroscopic impact fracture mode of CRT depended on the tensile stress at the edge of panel face and a criterion of the implosion was proposed.

It is well known that the strength characteristics of the glass used for the cathode ray tubes usually has a distinct scatter under the influence of surface flaws. Therefore, it is important to consider the variations in the static and delayed fracture strength of glass for the reliable design of vacuum cathode ray tubes under the atmospheric pressure. In this study, static and delayed fracture strength tests of glass were carried out using polished, abraded and scratched surface specimens in atmosphere in order to investigate the influence of the surface conditions on the strength characteristics statistically. From the goodness of fit test by the chi-square (x2) methed, the validity of the assumed distribution of the cumulative failure probability on the static and delayed fracture strength corresponding to each surface condition are discussed. Moreover, the statistical properties of the relationships between the static and delayed strengths are examined.

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