The ant, Formica japonica, is polyphagous and workers hunt other insects as foods. In this study, interspecific aggression was examined in the workers and queens. Behavior experiments demonstrated that interspecific aggressiveness was significantly higher in workers than queens. Workers showed predatory aggressive behavior towards crickets, on the other hand, queens elicited threat behavior but they didn’t attack crickets. In order to investigate neuronal mechanisms underlying regulation of aggressive motivation, the role of biogenic amine in the brain in evoking aggressive behavior was examined by measuring biogenic amine using high-performance liquid chromatography (HPLC) with electrochemical detection (ECD). No significant difference in the octopamine (OA) level was found between workers and queens, but the level of N-acetyloctopamine (NacOA) in the brain of queens was significantly higher than that of workers. This study suggests that OAergic system in the brain must involve in controlling aggressive motivation in the ants.
Biogenic amine serotonin (5-HT) modulates various aspects of behaviors such as aggressive behavior and circadian behavior in the cricket. In our previous report, in order to elucidate the molecular basis of the cricket 5-HT system, we identified three genes involved in 5-HT biosynthesis, as well as four 5-HT receptor genes (5-HT1A, 5-HT1B, 5-HT2α, and 5-HT7) expressed in the brain of the field cricket Gryllus bimaculatus DeGeer . In the present study, we identified Gryllus 5-HT2β gene, an additional 5-HT receptor gene expressed in the cricket brain, and examined its tissue-specific distribution and embryonic stagedependent expression. Gryllus 5-HT2β gene was ubiquitously expressed in the all examined adult tissues, and was expressed during early embryonic development, as well as during later stages. This study suggests functional differences between two 5-HT2 receptors in the cricket.
In order to reveal the reactivity of toluenethiols, the hydrogen isotope exchange reaction between one of three toluenethiols (o–,m–, andp–) and poly (vinyl alcohol) labeled with tritium was observed at 50 90°C. The reaction was analyzed with both the data obtained and theA
-McKay plot method, and the following has been quantitatively clarified: (1) the reactivity order of toluenethiols is (o–>(m–)>(p–); (2) the temperature dependences of the reactivity of toluenethiols are nearly equal; (3) the reactivity of benzenethiol is considerably decreased by the CH3 group bonded to the ortho position.
Aggressive behavior of white-eye mutant crickets was investigated and compared with that of wild-type crickets. In the dark, wild-type pairs performed long-lasting fights with significantly higher aggressive levels compared to those in the light. In contrast, fights between two white-eye mutants were not significantly different with those between two wild-type crickets both in duration and the aggressive levels. Ethograms of aggressive behavior showed that the mutants could show typical sequentially escalating fight with the same behavioral categories as the wild-type crickets. These results indicate that the white-eye mutants are able to express normal aggressive behavior.
Time resolved Mössbauer spectra were measured for57Co-labelled Co/IO3/2 using a delayed coincidence technique. A life-time for unstable57Fe(II)-species formed through EC-decay was estimated to be 43±5 ns at room temperature and the initial distribution of57Fe(II)/57Fe(III) at 14.4 keV nuclear level to be 0.47±0.13. The results are discussed in terms of electron transfer from the decayed57Fe(II) atoms to iodate ions.
Reaction products of ferrocenophane with CF3COOH, CCl3COOH, CF3SO3H and SbCl5 were prepared. Mössbauer spectroscopic data and magnetic susceptibility measurements suggest the bond formation of Fe–H+ and Fe–Cl+, in which iron atoms are in a high-spin Fe/II/state.
Authors:T. Fujii, H. Yamana, M. Watanabe, and H. Moriyama
Extraction behaviors of Pd(II) in the TRUEX and PUREX solvent extractions were studied by using octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide. The effect of scrubbing in the TRUEX solvent extraction was demonstrated by adding oxalic acid. The distribution ratios of palladium (DPd's) in the diluted region of [HNO3] were found to depend strongly on the fraction of cationic species, Pd(NO3)+, existed in the aqueous phase. The gradual decrease of DPd with the increase of acidity beyond [H+] 1 mol·dm-3 was controlled by the formation of the anionic species Pd(NO3)3-.
Authors:T. Fujii, H. Yamana, K. Takamiya, M. Watanabe, and H. Moriyama
Adsorption behavior of fission products in nitric acid solution on various alloys and metals was studied by using a multitracer produced by neutron irradiation of UO2. The adsorption behavior of the fission products 99Mo, 131I, 132Te, 140La, and 143Ce, and 239Np was simultaneously studied. Some chemical decontamination tests were also examined. Clear adsorption of 99Mo, 131I, and 132Te was observed, whereas adsorption of 140La, 143Ce, and 239Np was not. The adsorption characteristics were discussed by considering anion-exchange reaction and surface complexation.
Authors:Y. Watanabe, M. Nakada, K. Endo, H. Nakahara, and H. Sano
KX-ray-gated emission Mössbauer spectra of57Co-labelled CoF2 and CoF2.2H2O were measured at room temperature, using the coincidence technique. A difference was found in the relative intensity of57Fe(II)/57Fe(III) between the X-ray-gated and non-gated emission spectra. The results are explained in terms of local radiolytic effects of water of crystallization and the chemical effects associated with the de-excitation processes caused by EC-decay.
Authors:T. Omori, K. Nagasaki, E. Watanabe, and H. Suganuma
A new spectrophotometric determination of technetium has been developed by means of the solvent extraction of tris(1,10-phenanthroline)iron(II) ([Fe(phen)32+]) with pertechnetate into nitrobenzene. The concentration of technetium can be determined by measuring the characteristic absorbance at 516 nm (=11,700M–1·cm–1) in the organic phase. An important feature of the proposed method is that the concentration of pertechnetate can be determined without complicated processes such as the reduction of pertechnetate and the subsequent formation of a colored chelate.