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We examined the effect of 20-hydroxyecdysone (20-HE), a neurosteroid found in insects that is involved in their developmental process, on both tonic convulsion and absence-like seizure in spontaneously epileptic rat (SER). When 20-HE was given orally to SER at 25-200 mg/kg, significant decreases of the tonic convulsion were observed with 100 and 200 mg/kg. Pretreatment of the animal with bicuculline (1 mg/kg, i.p.) antagonized the inhibitory effects of 20-HE. However, absence-like seizures were not affected by 20-HE. These findings indicate that 20-HE produces antiepileptic effects on tonic convulsion by acting on the modulatory site of GABA(A) receptors.

Crystal growth of MF2 (M = Ca, Sr, and Ba) is carried out under two different reactive atmospheres, HF and HF + CF4, with the same carrier gas (He). The effect of processing is seen in a comparison of the optical transparency in the near infrared of the single-crystal specimens.

Low-lying states in 96 Tc excited through the 96 Mo(d, 2nγ) reaction have been investigated by means of on-line internal conversion electron and γ-ray spectroscopy. Measured singles spectra and relative excitation functions together with particle-γ and γ-γ coincidences were used to identify and fit the transitions in a level scheme. The low-lying positive-parity states 2 + –7 + and negative-parity states 2 − and 3 − are compared with those appearing systematically in doubly odd 94, 98 Tc and 92–96 Nb isotopes. Comparison is also made with simple shell-model calculations for those nuclei based on the π( p 1 2 , g 9 2 ) p ν ( d 5 2 ) n configuration space and the tendency of the multiplet structure of the wave functions is discussed.

The first forbidden beta transitions from 205Tl to low-lying states in 205Pb, which are induced by capturing very low-energy neutrinos, are investigated theoretically. A result of a tentative calculation is presented. Several problems in shell-model calculations of these nuclei and in the evaluation of the beta matrix elements are discussed towards a more quantitative prediction.

Crystal growth of MF2 (M = Ca, Sr, or Ba) is carried out in a reactive atmosphere consisting of HF and a carrier gas (He). Single-crystal Bridgman ingots, with the axis oriented at 〈111〉, are grown up to 5.2 cm in diameter. The mechanical strength of these specimens is found to be higher than what has been reported.

By ferricyanide oxidation of 2-(4-methoxyphenyl)phenanthro[9,10- d ]imidazole, three new photochromic compounds were obtained. These were 4-ethoxy-4H-, 4-methoxy-4H- and 2-methoxy-2H-phenanthro[9,10- d ]imidazoles. These compounds gave the 2-(4-methoxyphenyl)-phenanthro[9,10- d ]imidazolyl radical and acetaldehyde or formaldehyde by light irradiation. The imidazolyl radical dimerized gradually in the dark and the dimer dissociated to the imidazolyl radical on heating.

The low-lying non-normal parity states of 209 Bi and 207 Pb are studied by means of the shell model, assuming 1h-2p and 2h-1p configurations, respectively. The observed energy spectra are well reproduced. The wave functions obtained are analysed in comparison with those defined in the weak-coupling model and existence of the octupole multiplet and the mixing with other states are discussed in detail. The conditions for the existence of the weak-coupling states are also discussed.

A description of steady-state partition is applied to 3d ions in the crystal growth of sulfates and fluosilicates. Preliminary results are given for 4f ions in fluorite. Solubility order in a given host shows the influence of CFSE (crystal field stabilization energy).

The shell model study has been carried out about the close septuplet of 209 Bi without assuming weak particle-vibration coupling. The energies and the wave functions of these states are discussed.