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We investigated the anisotropy of the magnetic and magnetocaloric properties of singlecrystalline double perovskite Tb2CoMnO6, which crystallizes in a monoclinic P21/n structure. Due to dissimilar magnetic anisotropy, the ferromagnetic order of the Co 2+ and Mn 4+ moments emerges along the c-axis at TC = 100 K, and the larger Tb 3+ moments align perpendicular to the c-axis, below TTb = 15 K. The intricate temperature development of the metamagnetism along the c-axis results in a large negative change in the magnetic entropy at low temperature. On the other hand, the larger but almost reversible magnetization, perpendicular to the c-axis, results in a small and positive entropy change. This highly anisotropic magnetocaloric effect (MCE) leads to a giant rotational MCE, estimated to be 20.8 J/kg·K. Our findings, based on the magnetic anisotropy in Tb2CoMnO6, enrich fundamental and applied research on magnetic materials, considering the distinct magnetic characteristics of double perovskites. * Electronic addresses: phylove@yonsei.ac.kr and eland@yonsei.ac.kr

When we evaluated changes of glial fibrillary acidic protein (GFAP) and two glutamate transporter (GTs) by immunohistochemistry, expression of GFAP showed a significant increase in complete Freund's adjuvant (CFA)-injected rats; however, this expression was strongly inhibited by electroacupuncture (EA) stimulation. Robust downregulation of glutamate-aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1) was observed in CFA-injected rats; however, EA stimulation resulted in recovery of this expression. Double-labeling staining showed co-localization of a large proportion of GLAST or GLT-1 with GFAP. Using Western blot, we confirmed protein expression of two GTs, but no differences in the mRNA content of these GTs were observed. Because EA treatment resulted in strong inhibition of CFA-induced proteasome activities, we examined the question of whether thermal sensitivities and GTs expression could be regulated by proteasome inhibitor MG132. CFA-injected rats co-treated with EA and MG132 showed a significantly longer thermal sensitivity, compared with CFA-injected rats with or without MG132. Both EA and MG132 blocked CFA-induced GLAST and GLT-1 downregulation within the spinal cord. These results provide evidence for involvement of GLAST and GLT-1 in response to activation of spinal astrocytes in an EA antinociceptive effect. Antinociceptive effect of EA may be induced via proteasome-mediated regulation of spinal GTs.

The electronic structure of the electrochemically Li-ion deintercalated Li 1Ϫx Al y Co 1Ϫy O 2 system has been investigated intensively with compositional x value variation using soft X-ray absorption spectroscopy ͑XAS͒ for oxygen K-edge and Co L II,III -edge. To get reasonably good XAS spectra for the electrochemically Li-ion deintercalated LiAl y Co 1Ϫy O 2 system, we made binder-free LiAl y Co 1Ϫy O 2 film electrodes using the electrostatic spray deposition technique. The spectral changes of the O K-edge XAS for LiAl y Co 1Ϫy O 2 during charging are relatively more dramatic than those of the Co L II,III -edge XAS. From the results of the spectral changes of the Co L-edge and O K-edge XAS between LiCoO 2 and LiAl 0.25 Co 0.75 O 2 during charging, it is concluded that the substitution of Al for Co ions in LiCoO 2 induces more increased oxygen participation in the charge compensation process during charging.Numerous studies on the electronic structure of cathode materials for Li rechargeable batteries have been made extensively. X-ray absorption spectroscopy ͑XAS͒ has been used to examine the electronic and local structure of the cathode materials. 1-4 The XAS study for the Li-ion intercalation-deintercalation has been mainly investigated from the viewpoint of metal ion. The absorption peak features of the metal K-edge XAS include useful structural information such as oxidation state of chemical species, their site symmetries, and covalent bond strength. Further, it is observed that the small preedge peak was used to infer the electronic structure of the central atom, since the transition is very sensitive to chemical environments, in spite of the electric dipole-forbidden transition. It has been reported that the Li-ion deintercalation in lithium transition metal oxide systems leads to the increase of average oxidation state of metal ion and the local structural distortion around the metal atom. However, the metal K-edge XAS could not give any direct information for participation of oxygen in the charge compensation process. Only indirect inference for the contribution of oxygen atoms was obtained from the peak intensity for electronic transition of 1s electron to 4p orbital with shakedown process.Recently, Ceder et al. reported higher open-circuit voltage ͑above ϳ4.0 V͒ both theoretically and experimentally by the partial substitution of nontransition metals like Al 3ϩ for Co 3ϩ ions in the LiCoO 2 structure. 5 In this case, it has been suggested that the electrochemical property of electron exchange is much associated with the participation of an oxygen 2p band, in addition to the charge compensation by the metal ion. It is very important to investigate the quantity of oxygen atom contribution on the charge compensation during the Li-ion intercalation-deintercalation process. Soft XAS technique is widely used for the quantitative study of electronic structures for various cobalt oxides. 6-12 Intensive absorption peaks of Co L II,III -edge XAS representing intense main 2p → 3d transition, unlike the weak pre-ed...