Current induced spin-orbit effective magnetic fields in metal/ferromagnet/oxide trilayers provide a new way to manipulate the magnetization, which is an alternative to the conventional current induced spin transfer torque arising from noncollinear magnetization. Ta/CoFeB/MgO structures are expected to be useful for non-volatile memories and logic devices due to its perpendicular anisotropy and large current induced spin-orbit effective fields. However many aspects such as the angular and temperature dependent phenomena of the effective fields are little understood. Here, we evaluate the angular and temperature dependence of the current-induced spin-orbit effective fields considering contributions from both the anomalous and planar Hall effects. The longitudinal and transverse components of effective fields are found to have strong angular dependence on the magnetization direction at 300 K. The transverse field decreases significantly with decreasing temperature, whereas the longitudinal field shows weaker temperature dependence. Our results reveal important features and provide an opportunity for a more comprehensive understanding of current induced spin-orbit effective fields.

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Ginsenosides are deglycosylated by intestinal bacteria to active forms after oral administration. The present study demonstrated the pharmacodynamics of 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol (M1), an intestinal bacterial metabolite of ginsenosides, and the in vitro and in vivo antitumor activities of M1-metabolites in comparison with M1 using C57BL/6 mice and Wistar rats. M1 was selectively accumulated into the liver soon after its intravenous administration to mice, and mostly excreted as bile; however, some M1 was transformed to fatty acid ester (EM1) in the liver. EM1 was isolated from rats in a recovery dose of approximately 24 mol%. Structural analysis indicated that EM1 comprised a family of fatty acid mono-esters of M1. Because EM1 was not excreted as bile as M1 was, it was accumulated in the liver longer than M1. Although the cytotoxicity of M1 against B16-F10 melanoma cells was attenuated by fatty acid esterification, EM1 inhibited tumor growth more than M1 in vivo. These results suggest that the fatty acid M1 esters may be the real active principles of ginsenosides in the body.

It is well known that a strong relationship exists between human voices and the movement of articulatory facial muscles. In this paper, we utilize this knowledge to implement an automatic speech recognition scheme which uses solely surface electromyogram (EMG) signals. The sequence of EMG signals for each word is modelled by a hidden Markov model (HMM) framework. The main objective of the work involves building a model for state observation density when multichannel observation sequences are given. The proposed model reflects the dependencies between each of the EMG signals, which are described by introducing a global control variable. We also develop an efficient model training method, based on a maximum likelihood criterion. In a preliminary study, 60 isolated words were used as recognition variables. EMG signals were acquired from three articulatory facial muscles. The findings indicate that such a system may have the capacity to recognize speech signals with an accuracy of up to 87.07%, which is superior to the independent probabilistic model.