Vasotocin-producing parvocellular neurones in the medial part of the bed nucleus of the stria terminalis (BSTM) of many species of birds and mammals show sexual dimorphism and great plasticity in response to hormonal and environmental stimuli. In the BSTM of Japanese quail, vasotocin-immunoreactive neurones are visible and sensitive to testosterone exclusively in males. In males, gonadectomy decreases and testosterone restores vasotocin-immunoreactive cells and fibres by acting on vasotocin mRNA transcription. The insensitivity of female vasotocin-immunoreactive neurones to the activating effects of testosterone is the result of organisational effects of early exposure to oestradiol. Female quail also show vasotocin mRNA-expressing neurones in the BSTM, although it is not known whether the insensitivity of the vasotocinergic neurones to testosterone originates at the level of vasotocin gene transcription in this sex. Therefore, initially, the present study analysed the effects of acute treatment with testosterone on vasotocin mRNA expression in the BSTM of gonadectomised male and female quail using in situ hybridisation. Gonadectomy decreased (and a single injection of testosterone increased) the number of vasotocin mRNA-expressing neurones and intensity of the vasotocin mRNA hybridisation signal similarly in both sexes. Notably, testosterone increased vasotocin mRNA expression in ovariectomised females over that shown by intact quail. However, this treatment had no effect on vasotocin immunoreactivity. A second experiment analysed the effects of testosterone metabolites, oestradiol and 5α-dihydrotestosterone, on vasotocin mRNA expression in female quail. Oestradiol (but not 5α-dihydrotestosterone) fully mimicked the effects of testosterone on the number of vasotocin mRNA-expressing neurones and the intensity of the vasotocin mRNA hybridisation signal. Taken together, these results show, for the first time, that gonadal steroids strongly activate vasotocin mRNA expression in the BSTM of female quail.

In order to study the low temperature process to fabricate (001) oriented FePt granular structure, FePt-Ag and FePt-MgO films were fabricated by the repetition process of deposition of Fe40Pt40Ag20 (0.83 nm) or Fe40Pt40(MgO)20 (0.83 nm) alloy layer and subsequent annealing at Ta = 200˚C-400˚C. The FePt-Ag film showed (001) oriented structure together with rather high ordering parameter of 0.5 even at a low process temperature of 250 ˚C. The ordering parameter of FePt-Ag was found to be much higher than that of FePt-MgO. The FePt-Ag prepared by the repetition process at 250 ˚C had well isolated grain structure with diameters of several nm to several tens nm, and showed a large uniaxial anisotropy of 1.0 x 10 7 erg/cc. The application of the repetition process and Ag addition into FePt was found to be quite effective to fabricate well isolated L10 ordered FePt granular structure at a low process temperature.

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