Pressure-Induced Antiferromagnetic Bulk Superconductor EuFe2_2As2_2

We present the magnetic and superconducting phase diagram of EuFe$_2$As$_2$ for $B \parallel c$ and $B \parallel ab$. The antiferromagnetic phase of the Eu$^{2+}$ moments is completely enclosed in the superconducting phase. The upper critical field vs. temperature curves exhibit strong concave curvatures, which can be explained by the Jaccarino-Peter compensation effect due to the antiferromagnetic exchange interaction between the Eu$^{2+}$ moments and conduction electrons.Comment: submitted to the proceedings of the M2S-IX Toky

Contrasting Pressure Effects in Sr2VFeAsO3 and Sr2ScFePO3

We report the resistivity measurements under pressure of two Fe-based superconductors with a thick perovskite oxide layer, Sr2VFeAsO3 and Sr2ScFePO3. The superconducting transition temperature Tc of Sr2VFeAsO3 markedly increases with increasing pressure. Its onset value, which was Tc{onset}=36.4 K at ambient pressure, increases to Tc{onset}=46.0 K at ~4 GPa, ensuring the potential of the "21113" system as a high-Tc material. However, the superconductivity of Sr2ScFePO3 is strongly suppressed under pressure. The Tc{onset} of ~16 K decreases to ~5 K at ~4 GPa, and the zero-resistance state is almost lost. We discuss the factor that induces this contrasting pressure effect.Comment: 5 pages, 4 figures, to be published in J. Phys. Soc. Jpn. No.12 (2009

Force Constants of Cu Crystals From Diffuse Neutron Scattering Measurement

Diffuse neutron scattering measurement on Cu crystals was performed at 10 K and 300 K. Oscillatory forms were observed in the diffuse scattering intensities. The observed diffuse scattering intensities are analyzed by including the correlation effects among thermal displacements of atoms in the theory. Using the values of correlation effects among neighboring atoms and the values of Debye-Waller temperature parameter, force constants among first, second and third nearest neighboring atoms have been evaluated. The result of correlation effects in Cu crystals are compared to that of ionic crystal and semiconductor. The relation between correlation effects and the inter-atomic distance is not depending much on the crystal binding types. Received: 12 October 2010; Revised: 22 October 2010; Accepted: 16 December 201

Derivation of Inter-Atomic Force Constants of Cu2O From Diffuse Neutron Scattering Measurement

Neutron scattering intensity from Cu2O compound has been measured at 10 K and 295 K with High Resolution Powder Diffractometer at JRR-3 JAEA. The oscillatory diffuse scattering related to correlations among thermal displacements of atoms was observed at 295 K. The correlation parameters were determined from the observed diffuse scattering intensity at 10 and 295 K. The force constants between the neighboring atoms in Cu2O were estimated from the correlation parameters and compared to those of Ag2O.Received: 16 January 2013; Revised: 10 April 2013; Accepted: 15 April 201

Intrinsic Properties of AFe2As2 (A = Ba, Sr) Single Crystal under Highly Hydrostatic Pressure Conditions

We measured the electrical resistivity and ac magnetic susceptibility of BaFe2As2 and SrFe2As2 single crystals under pressure using a cubic anvil apparatus. For BaFe2As2, the antiferromagnetic (AF) and structural transitions are suppressed with increasing pressure. Unexpectedly, these transitions persist up to 8 GPa, and no signature of a superconducting transition was observed in the pressure range investigated here. On the other hand, the AF and structural transitions of SrFe2As2 collapse at around the critical pressure Pc ~ 5 GPa, resulting in the appearance of bulk superconductivity. The superconducting volume fraction abruptly increases above Pc, and shows a dome centered at approximately 6 GPa. Our results suggest that the bulk superconducting phase competes with the AF/orthorhombic phase and only appears in the narrow pressure region of the tetragonal phase.Comment: 4 pages, 4 figures; accepted for publication in J. Phys. Soc. Jp

Single crystals of LnFeAsO1-xFx (Ln=La, Pr, Nd, Sm, Gd) and Ba1-xRbxFe2As2: growth, structure and superconducting properties

A review of our investigations on single crystals of LnFeAsO1-xFx (Ln=La, Pr, Nd, Sm, Gd) and Ba1-xRbxFe2As2 is presented. A high pressure technique has been applied for the growth of LnFeAsO1-xFx crystals, while Ba1-xRbxFe2As2 crystals were grown using quartz ampoule method. Single crystals were used for electrical transport, structure, magnetic torque and spectroscopic studies. Investigations of the crystal structure confirmed high structural perfection and show less than full occupation of the (O, F) position in superconducting LnFeAsO1-xFx crystals. Resistivity measurements on LnFeAsO1-xFx crystals show a significant broadening of the transition in high magnetic fields, whereas the resistive transition in Ba1 xRbxFe2As2 simply shifts to lower temperature. Critical current density for both compounds is relatively high and exceeds 2x109 A/m2 at 15 K in 7 T. The anisotropy of magnetic penetration depth, measured on LnFeAsO1-xFx crystals by torque magnetometry is temperature dependent and apparently larger than the anisotropy of the upper critical field. Ba1-xRbxFe2As2 crystals are electronically significantly less anisotropic. Point-Contact Andreev-Reflection spectroscopy indicates the existence of two energy gaps in LnFeAsO1-xFx. Scanning Tunneling Spectroscopy reveals in addition to a superconducting gap, also some feature at high energy (~20 meV).Comment: 27 pages, 19 figures, 2 tables, accepted to the special issue of the Physica C on superconducting pnictide

Serum galectin-9 levels are elevated in the patients with type 2 diabetes and chronic kidney disease

Background: Galectin-9 (Gal-9) induces apoptosis in activated T helper 1 (T(H)1) cells as a ligand for T cell immunoglobulin mucin-3 (Tim-3). Gal-9 also inhibits the G1 phase cell cycle arrest and hypertrophy in db/db mice, the hallmark of early diabetic nephropathy, by reversing the high glucose-induced up-regulation of cyclin dependent kinase inhibitors such as p27(Kip1) and p21(Cip1). Methods: We investigated the serum levels of Gal-9 in the patients with type 2 diabetes and various stages of chronic kidney disease (CKD) (n = 182). Results: Serum Gal-9 levels in the patients with type 2 diabetes were 131.9 +/- 105.4 pg/ml and Log(10)Gal-9 levels significantly and positively correlated with age (r = 0.227, p = 0.002), creatinine (r = 0.175, p = 0.018), urea nitrogen (r = 0.162, p = 0.028) and osmotic pressure (r = 0.187, p = 0.014) and negatively correlated with estimated glomerular filtration rate (eGFR) (r = -0.188, p = 0.011). Log(10)Gal-9 levels increased along with the progression of GFR categories of G1 to G4, and they were statistically significant by Jonckheere-Terpstra test (p = 0.012). Log(10)Gal-9 levels remained similar levels in albuminuria stages of A1 to A3. Conclusion: The elevation of serum Gal-9 in the patients with type 2 diabetes is closely linked to GFR and they may be related to the alteration of the immune response and inflammation of the patients with type 2 diabetes and CKD

Crystal and magnetic structure of the superconductor CeNi0.8_{0.8}Bi2_2

We have performed powder neutron diffraction on the new superconductor, CeNi$_{0.8}$Bi$_2$ with a superconducting transtion temperature $T_\textrm{c} \sim$ 4.2 K. The structural parameters of this compound at room temperature are determined by Rietveld analysis. Below about 5 K, the clear magnetic Bragg peaks with propagation vector $q$=(0 0 0) are observed. The observed intensities of magnetic Bragg peaks can be explained by the magnetic structure that the two Ce moments in the unit cell are antiparallel along c axis. The magnetic Bragg peaks are observed in the superconducting state, indicating the coexistence of the antiferromagnetic ordering and the superconductivity in this compound. The intensity of magnetic Bragg peak monotonously increases with decreasing temperature below $T_\textrm{N}$ and does not exhibit apparent anomaly at $T_\textrm{c}$, obviously different from cases of heavy fermion superconductors in which the magnetic ordering and the superconductivity coexist, for example, Cd-doped CeCoIn$_5$. These results suggest that the 4$f$ electron of the Ce atom is not coupled with the superconducting carrier, and the magnetic ordering is almost independent of the superconductivity in CeNi$_{0.8}$Bi$_2$.Comment: 5 pages, 4 figure

A review of the long-term psychological effects of radiation exposure in the cases of the atomic bombings of Hiroshima and Nagasaki and the Chernobyl nuclear accident

The unique history of nuclear weapons and nuclear power have created a host of unintended knock-on consequences to individuals and societies across the world through their development and deployment. This paper reviews the cases of the atomic bombings of Hiroshima and Nagasaki and the nuclear accident at Chernobyl for long-term effects on human psychological and social processes in victims and their families. Key aspects to the psychology of the atomic bomb experience were the phenomenon of “silence” in survivors and an anxiety about the possible unknown health and genetic effects of exposure, with relatively few issues observed in descendants. Children, women, clean-up workers, and migrants are known to be vulnerable or at-risk populations for mental health issues in Chernobyl. Implications for future research in this domain are discussed

Alveolar soft-part sarcoma of the retroperitoneum

The definitive version is available at www.blackwell-synergy.com.ArticleInternational Journal of Urology. 13(10): 1355-1357 (2006)journal articl