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Abstract: Quasi-particle dispersion relations were calculated within the Migdal approximation for the tunneling spectral function of the electron–phonon interaction obtained by us in slightly overdoped Bi2Sr2CaCu2O8. These relations were compared with the photoelectron results by Gweon et al. If a linear dispersion relation is assumed for a bare state, considerable discrepancies are observed. However, many similarities are noted with regard to local changes in the dispersion relations such as a kink, a discontinuity at the maximum phonon frequency, and an isotope shift in a single-phonon frequency range. [Copyright &y& Elsevier]

In uncertain choice situations, we deliberately search and evaluate possible options before taking an action. Once we form a preference regarding the current situation, we take an action more automatically and with less deliberation. In rats, the deliberation process can be seen in vicarious trial-and-error behavior (VTE), which is a head-orienting behavior toward options at a choice point. Recent neurophysiological findings suggest that VTE reflects the rat's thinking about future options as deliberation, expectation, and planning when rats feel conflict. VTE occurs depending on the demand: an increase occurs during initial learning, and a decrease occurs with progression in learning. However, the brain circuit underlying the regulation of VTE has not been thoroughly examined. In situations in which VTE often appears, the medial prefrontal cortex (mPFC) and the amygdala (AMY) are crucial for learning and decision making. Our previous study reported that noradrenaline regulates VTE. Here, to investigate whether the mPFC and AMY are involved in regulation of VTE, we examined the effects of local injection of clonidine, an alpha2 adrenergic autoreceptor agonist, into either region in rats during VTE and choice behavior during a T-maze choice task. Injection of clonidine into either region impaired selection of the advantageous choice in the task. Furthermore, clonidine injection into the mPFC suppressed occurrence of VTE in the early phase of the task, whereas injection into the AMY inhibited the decrease in VTE in the later phase and thus maintained a high level of VTE throughout the task. These results suggest that the mPFC and AMY play a role in the increase and decrease in VTE, respectively, and that noradrenergic mechanisms mediate the dynamic regulation of VTE over experiences., (Copyright © 2015 Elsevier B.V. All rights reserved.)

We have successfully synthesized Sr(2)V(1-x)Mo(x)O(4) from x = 0.3 to 1.0 by an improved process. The layered compound Sr(2)VO(4) is an antiferromagnetic insulator with S = 1/2, while the isostructural Sr(2)MoO(4) is a Pauli paramagnetic metal. The solid solution Sr(2)V(1-x)Mo(x)O(4) of these materials is expected to show a metal-insulator transition. In this paper we report the synthetic process and the results of the magnetic susceptibility and the electrical resistivity. The selection of the starting materials and the adjustment of O(2) partial pressure of less than 10(-12) atm were indispensable for the synthesis. The reducing conditions during the sintering had been determined rationally, according to thermodynamical analysis. Kondo-like behavior in both resistivity and magnetic susceptibility were observed in a limited range of V-containing samples.