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We present two distorted face-centered cubic (dfcc) structures of yttrium under high pressure, which have been found by a first-principles genetic algorithm technique. The structures are a tetragonalP43(dfcc-I) and a triclinicP1¯ (dfcc-II), formed by slight distortions from a trigonalR3¯mstructure reported as the dfcc phase earlier. The enthalpy difference between the two dfcc structures is less than 0.2 mRy/atom, and dfcc-I is marginally more stable than dfcc-II in lower pressure region. The enthalpy comparison among candidate structures indicates the structural phase transitions into dfcc-I at 41 GPa, into dfcc-II at 81 GPa, and into an orthorhombicFdddstructure at 106 GPa. [ABSTRACT FROM PUBLISHER]

In this paper, the dynamical behavior of simple cubic (sc) calcium is investigated by first-principles molecular dynamics (MD) simulation at 40 GPa and 300 K and is compared with that of sc phosphorus. As a result, we found that calcium shows larger structural fluctuation through the MD simulation than phosphorus but the dynamical structures of calcium and phosphorus both become the sc structure. On the other hand, performing a structural optimization in the course of the MD simulation, we obtained that phosphorus and calcium take the sc structure and a distorted sc structure, respectively, and the static structures of calcium and phosphorus are inconsistent with each other. These results indicate that sc calcium is stabilized by thermal effects, which is quite different from the stabilization process of sc phosphorus. [ABSTRACT FROM PUBLISHER]

Abstract: Can we expect the appearance of superconductivity from magnetic elements? In general, superconductivity occurs in nonmagnetic metal at low temperature and magnetic impurities destroy superconductivity; magnetism and superconductivity are as incompatible as oil and water. Here, we present our experimental example of superconducting elements, iron and oxygen. They are magnetic at ambient pressure, however, they become nonmagnetic under high pressure, then superconductor at low temperature. What is the driving force of the superconductivity? Our understanding in the early stages was a simple scenario that the superconductive state was obtained as a consequence of an emergence of the nonmagnetic states. In both cases, we may consider another scenario for the appearance of superconductivity; the magnetic fluctuation mechanism in the same way as unconventional superconductors. [Copyright &y& Elsevier]

Pressure-induced stacking sequence variations of gold are predicted from first-principles calculations. At the static condition, the ABC stacking in the face-centered-cubic (fcc) phase changes into ABCACB above at least 200 GPa, and then into ABAC corresponding to the double hexagonal-close-packed structure. By further compression, the hexagonal-close-packed (hcp) structure with the AB stacking emerges as the most stable structure of all the stacking structures. This sequence of the transitions shows a step-by-step increase of the hexagonality over a wide pressure range. The calculations of phonon free energy indicate that the stable region of the intermediate stacking structures between fcc and hcp such as ABCACB or ABAC gets to be narrow with increase of temperature and fcc directly transforms into hcp above 400 K. This direct transition from fcc to hcp is qualitatively consistent with the earlier experimental observations. [ABSTRACT FROM AUTHOR]

The superconductivity of gold–indium alloys has been investigated using first-principles calculations based on the density functional theory. At ambient pressure, the calculated superconducting transition temperature (Tc) is 0.04 μ K in pure gold, butTcdramatically increases by substituting indium atoms for gold atoms. The gold–indium alloy having 12.5 atomic percent indium (Au0.875In0.125) showsTcof 0.1 K, and Au0.75In0.25marks 1.7 K. The dramatic increase inTcowing to the alloying effect is caused by the enhancement of the electron–phonon coupling. The superconductivity of gold is predicted to be drastically weakened with increasing pressure and virtually disappear at 10 GPa, but it continues up to at least 30 GPa by the inclusion of indium atoms. [ABSTRACT FROM AUTHOR]

Pulmonary metastasis from leiomyosarcoma is rare and its clinical management is challenging. A single lung metastasis from a perineal leiomyosarcoma occurred in a 79-year-old woman. Five months after resection of the lung metastasis, a new metastatic tumor developed in the contralateral lung. Since the patient did not desire to receive hospitalized treatment, TS-1 (an oral agent consisting of a combination of tegafur, gimeracil, and oteracil potassium) therapy was started on an outpatient basis. The lung metastasis has been successfully controlled for at least 17 months with excellent tolerability The clinical features and the treatment of this case are discussed. [ABSTRACT FROM AUTHOR]

Background. A very few cases of biopsy-proven tubulointerstitial nephritis (TIN) in patients with primary biliary cirrhosis (PBC) have been reported. Although the clinical importance of this association has been suggested, information on its clinicopathological features and prognosis is limited.Methods. We reviewed 5955 renal biopsies processed at our department, and identified four patients with TIN associated with asymptomatic PBC. We evaluated clinicopathological features and outcomes in these patients, and reviewed the previously reported cases of TIN associated with PBC.Results. Our four patients were female. The patients’ age at the time of renal biopsy ranged from 36 to 77. Three patients had been treated with ursodeoxycholic acid. All patients had urinary abnormalities such as proteinuria and elevated levels of urinary β2-microglobulin, and three patients had renal insufficiency. All patients had distal renal tubular acidosis (RTA), and two patients also had Fanconi syndrome. Renal biopsy showed severe lymphocyte infiltration in the tubules and interstitium with mild-to-moderate tubular atrophy and fibrosis. All patients responded well to steroid therapy. On review of the previously reported five cases, all patients were female. The patients’ age ranged from 42 to 68. Apparent symptoms linked to PBC were not described. All patients had renal insufficiency. Three patients suffering from bone pains or bone fractures also had Fanconi syndrome. Marked or transient improvements were observed after steroid therapy in three patients.Conclusions. TIN and RTA of different types are extremely rare but one of the important extrahepatic complications of PBC. Steroid therapy can be beneficial in treating PBC patients with these renal complications. [ABSTRACT FROM AUTHOR]

Modulated structures in phosphorous and iodine at high pressure have been studied by ab-initio calculations. In phosphorous the electrostatic interaction between the charge density, i.e. Ewald energy Eew and Hartree energy Eh play an important role for the creation of the modulated structure, whereas such roles of Eew and Eh are not observed in iodine. Results of a detailed study of the electronic properties are shown and discussed for phosphorous in comparison with those of iodine. Superconductivity in these materials has been discussed in relation to those properties. [ABSTRACT FROM AUTHOR]

Abstract: To determine the effective spin model of the nano scale ferrimagnetic ring [Mn(hfac)2NITPh]6 abbreviated as Mn6R6, we propose a new criterion that the model should reproduce spatial configuration of the local spin densities of the reference system calculated by the hybrid density functional theory. The new prescription to Mn6R6 is successfully applied to clarify that the effective spin model consists of not only the nearest neighbor antiferromagnetic interaction but also the next nearest neighbor antiferromagnetic interaction which causes frustration in the spin system. The present result suggests that the spatial configuration of the spin densities gives an essential information for the determination of the effective spin model. [Copyright &y& Elsevier]

Abstract: Size dependence of the magnetic properties in nanoscale ferrimagnetic rings is investigated by the numerical diagonalization of the Heisenberg model. The field derivative of the magnetization is drastically dependent on size of the ring if the magnetic system has frustration, although the character does not exist in the non-frustrated system. Our numerical data support this tendency that the effect of frustration causes the size dependence of the magnetic properties in the nanoscale ferrimagnetic ring. We also demonstrate that the size dependence caused by frustration is also found in behavior of the translational quantum number of the ground state. [Copyright &y& Elsevier]

Pressure dependencies of electronic structures and lattice dynamics of Pd which is close to ferromagnetic instability at ambient pressure are investigated on the basis of first-principles calculations. Particular attention is paid to phonon-mediated superconductivity: the transition temperature Tc without taking into account spin fluctuation effects are estimated to be 6.40–8.55 K at ambient pressure and 0.58–1.44 K at 50 GPa. Though spin fluctuation effects would suppress the superconducting transition at 0 GPa, under pressures the transition would appear due to the rapid decreasing of spin fluctuation effects with increasing pressure. We estimate the Tc at 50 GPa to be at most 0.71 K if we include spin fluctuation effects. [Copyright &y& Elsevier]