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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...

<i>Clonorchis sinensis</i> is the most common fish-borne intestinal parasite in Korea. The aim of the present investigation was to survey the status of <i>C. sinensis</i> infection and analyze associated risk factors in residents of Haman-gun, Gyeongsangnam-do. A total of 5,114 residents from 10 administrative towns/villages voluntarily agreed to participate in the study, which comprised fecal examination, a questionnaire survey for risk factors, ultrasonography, and enzymelinked immunosorbent assay for cancer biomarker detection in the blood. We detected <i>C. sinensis</i> eggs in 5.3% of the subjects. By region, Gunbuk-myeon had the highest number of residents with <i>C. sinensis</i> eggs. The infection rate and intensity were higher in male than in female residents. Based on the risk factor questionnaire, infection was highly associated with drinking, a history of <i>C. sinensis</i> infection, and the practice of eating of raw freshwater fish. Extension of the bile duct, infection intensity, and cancer biomarker detection significantly correlated with the presence of eggs in the study population. In conclusion, the development of feasible, long-term control policies and strategies for the elimination of <i>C. sinensis</i> in Korea is still required.

We have conducted a terahertz spectroscopic study of antiferromagnetic resonances in bulk orthoferrite YFe1−xMnxO3 0≤x≤0.4. Both the quasi-ferromagnetic resonance mode and the quasi-antiferromagnetic resonance mode in the weak ferromagnetic Γ4 phase disappear near the spin reorientation temperature, TSR, for the onset of the collinear antiferromagnetic Γ1 phase (x ≥ 0.1). Below TSR, an antiferromagnetic resonance mode emerges and exhibits a large blueshift with decreasing temperature. However, below 50 K, this mode softens considerably, and this tendency becomes stronger with Mn doping. We provide a deeper understanding of such behaviors of the antiferromagnetic resonance modes in terms of the influence of the Mn3+ ions on the magnetocrystalline anisotropy. Our results show that terahertz time-domain spectroscopy is a useful, complementary tool in tracking magnetic transitions and probing the interaction between disparate magnetic subsystems in antiferromagnetic materials with multiple ionic species.

Placenta is a special organ that contains many nutrients such as growth factors, minerals, and bioactive peptides. Dipeptides of glycine and leucine are major components of porcine placenta extracts (PPE) that has been used as an alternative of human placenta extracts. In this study, we investigated whether major peptides of PPE, Glycyl-L-Leucine (Gly-Leu), L-Leucyl-Glycine (Leu-Gly), and L-Leucyl-L-Leucine (Leu-Leu), affect skin hydration and elasticity in vitro and in vivo. We found that Gly-Leu and Leu-Gly dipeptides induced the expression of transglutaminase 1 in normal human epidermal keratinocytes (NHEKs) whereas Leu-Leu dipeptides did not. Treatment with Gly-Leu or Leu-Gly significantly increased hyaluronan (HA) synthesis in NHEKs and the upregulation of hyaluronan synthase 2 (HAS2) mRNA level was confirmed. In addition, elastase activity was inhibited in NHEKs treated with Gly-Leu or Leu-Gly dipeptides. Oral administration of Gly-Leu or Leu-Gly dipeptides increased skin hydration and elasticity in UVB-irradiated hairless mice. The significant upregulation of HA in UVB-irradiated hairless mice was observed in response to oral administration of Gly-Leu or Leu-Gly. These results suggest that the major dipeptides of porcine placenta, Gly-Leu and Leu-Gly, are potentially active ingredients for skin moisturization formulations.