Parrots and songbirds learn their vocalizations from a conspecific tutor, much like human infants acquire spoken language. Parrots can learn human words and it has been suggested that they can use them to communicate with humans. The caudomedial pallium in the parrot brain is homologous with that of songbirds, and analogous to the human auditory association cortex, involved in speech processing. Here we investigated neuronal activation, measured as expression of the protein product of the immediate early gene ZENK, in relation to auditory learning in the budgerigar (Melopsittacus undulatus), a parrot. Budgerigar males successfully learned to discriminate two Japanese words spoken by another male conspecific. Re-exposure to the two discriminanda led to increased neuronal activation in the caudomedial pallium, but not in the hippocampus, compared to untrained birds that were exposed to the same words, or were not exposed to words. Neuronal activation in the caudomedial pallium of the experimental birds was correlated significantly and positively with the percentage of correct responses in the discrimination task. These results suggest that in a parrot, the caudomedial pallium is involved in auditory learning. Thus, in parrots, songbirds and humans, analogous brain regions may contain the neural substrate for auditory learning and memory.

Life cycle time expansion of equipments and deviees such as internal combustion engines become big issues under heat loads． ］ 「 bpology optimization for heat diffusion is one ofexpected solution to overcome this problem ． This papor has tried to establish a topology design optimization method of coupled state med by COMSOL Multiphysics ． As a 丘rst step to this purpose， we have solved topology optimization problems of heat dif 出sion by SMP method ． Several numerica ［design exarnples are implemented in order to Oon 且rm the validity ofoptlmum design ofheat dif 『 Usion ． Key Words ：( 初 砌 翻燗 D 碑 g埆 7 ウ ρ 010gy ( 旗 伽 砌 ' ion Heat Dt71is め n ， Mu -勿 伽廊 5

We have studied the energy band diagram for the Si surface and SiO 2 /Si system by using ultraviolet photoelectron spectroscopy (UPS) measurements. In the UPS measurements, monochromatized vacuum ultraviolet with variable incident photon energies below 10.50 eV was used in order to increase the detection limit of the depth from the surface and to understand the electronic states not only at the surface but also in the region near the interface of the stacked structure. From the incident photon energy dependence of the UPS spectral width, the energy level of the valence band top of the H-terminated Si surface and the electrical potential change in the SiO 2 /Si structure has been evaluated. Also, the vacuum work function value of the hetero-epitaxial Ag(111) surface has been investigated to check this measurement technique.

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