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71.

An ordered structure, which was found in a decagonal quasicrystal with 0.4 nm periodicity in a conventionally solidified Al70Ni20Ru10 alloy, has been examined theoretically by the projection of an ordered body-centred (CsCl-type) hypercubic lattice. The ordered structure can be characterized as an ordered arrangement of two kinds of atom columnar cluster with different directions of pentagonal symmetry. Two lattices, which are constructed by connecting the atom clusters in the same directions, can be interpreted as ordered sublattices formed by each of vertex and body-centred positions of the CsCl-type hypercubic lattice. Diffraction patterns calculated from the ordered and disordered body-centred hypercubic lattices replicate well the electron diffraction patterns observed from the Al-Ni-Ru and other decagonal quasicrystals.  相似文献   
72.
A W-(AlCoNi) crystalline approximant, which is closely related to Al–Co–Ni decagonal quasicrystals, in an Al72.5Co20Ni7.5 alloy has been studied by atomic resolution energy-dispersive X-ray spectroscopy (EDS), in an instrument attached to a spherical aberration (Cs)-corrected scanning transmission electron microscope. On high-resolution EDS maps of Co and Ni elements, obtained by integrating many sets of EDS data taken from undamaged areas, chemical ordering of Co and Ni is clearly detected. In the structure of the W-(AlCoNi) phase, consisting of arrangements of transition-metal (TM) atoms located at vertices of pentagonal tilings and pentagonal arrangements of mixed sites (MSs) of TM and Al atoms, Co atoms occupy the TM atom positions with the pentagonal tiling and Ni is enriched in part of the pentagonal arrangements of MSs.  相似文献   
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74.
A series of studies examined whether political participation can emerge from general patterns of indiscriminate activity. In the first two studies, general action tendencies were measured by combining national and state-level indicators of high activity (e.g., impulsiveness, pace of life, and physical activity) from international and U.S. data. This action-tendency index positively correlated with a measure of political participation that consisted of voting behaviors and participation in political demonstrations. The following two experimental studies indicated that participants exposed to action words (e.g., go, move) had stronger intentions to vote in an upcoming election and volunteered more time to make phone calls on behalf of a university policy than participants exposed to inaction words did (e.g., relax, stop). These studies suggest that political participation can be predicted from general tendencies toward activity present at the national and state levels, as well as from verbal prompts suggestive of activity.  相似文献   
75.
We applied near-infrared spectroscopy (NIRS) and electrocorticography (ECoG) recordings during cortical stimulation to a temporal lobe epilepsy patient who underwent subdural electrode implantation. Using NIRS, changes in blood concentrations of oxyhemoglobin (HbO(2)) and deoxyhemoglobin (HbR) during cortical stimulation of the left language areas were measured in each hemisphere. NIRS revealed that 2Hz stimulation with 5mA produced no significant hemodynamic changes in either hemisphere. By contrast, 50Hz stimulation elicited significant increases in both HbO(2) and HbR at the stimulation site. Furthermore, with 50Hz stimulation of the left superior temporal gyrus, the increases in HbO(2) and HbR were observed not only at the stimulation site but also concurrently at the left inferior frontal gyrus. This suggests the existence of functional connectivity in the language system. The present study demonstrates that simultaneous NIRS and ECoG studies during cortical stimulation allow a novel analysis of cerebral connectivity.  相似文献   
76.
Object We investigated an association between the polymorphism of brain-derived neurotrophic factor (BDNF) gene Val66Met and the response to mirtazapine in Japanese patients with major depressive disorder (MDD). We also examined mirtazapine's effects on the serum BDNF and plasma levels of catecholamine metabolites in these patients. METHODS: Eighty-four patients who met the DSM-IV-TR criteria for MDD were treated with only mirtazapine for 4 weeks. The BDNF Val66Met polymorphism was detected by direct sequencing in the region, and serum BDNF levels and plasma levels of catecholamine metabolites were measured by ELISA and HPLC-ECD, respectively. RESULTS: Mirtazapine treatment for 4 weeks significantly increased serum BDNF levels in the responders, whereas nonresponders showed significant decreases. No association was found between either of the two genotypes (Val/Val vs. Met-carriers) and the response to mirtazapine at T4 or the serum BDNF levels at T0. Mirtazapine did not alter the plasma levels of homovanillic acid (HVA) or 3-methoxy-4-hydroxyphenylglycol (MHPG). Discussion The dynamics of serum BDNF levels, but not plasma levels of HVA and MHPG, reflect the response to mirtazapine treatment; the BDNF Val66Met polymorphism in patients with depression is, however, associated with neither a particular response to mirtazapine treatment nor baseline serum BDNF levels. Conclusion Serum BDNF levels, but not plasma levels of HVA or MHPG, and BDNF Val66Met polymorphism are related to the mirtazapine response in MDD.  相似文献   
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