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We report the transport and thermodynamic properties under hydrostatic pressure in the antiferromagnetic Kondo compound CeMg2Cu9 with a two-dimensional arrangement of Ce atoms. Magnetic specific heat Cmag(T) shows a Schottky-type anomaly around 30 K originating from the crystal electric field (CEF) splitting of the 4f state with the first excited level at \Delta_{1}/kB = 58 K and the second excited level at \Delta_{2}/kB = 136 K from the ground state. Electric resistivity shows a two-peaks structure due to the Kondo effect on each CEF level around T_{1}^{max} = 3 K and T_{2}^{max} = 40 K. These peaks merge around 1.9 GPa with compression. With increasing pressure, Neel temperature TN initially increases and then change to decrease. TN finally disappears at the quantum critical point Pc = 2.4 GPa., Comment: 10 pages, 6 figures

We have carried out the specific heat C P ( T ) measurements on CeMg 2 ( Cu 1 - x Ni x ) 9 ( x = 0 and 0.02) in which the Ce atoms are a two-dimensional arrangement. The large anomalies are observed at the Neel temperature T N = 2.5 and 1.7 K for x = 0 and 0.02, respectively. The magnetic specific heat C mag (T) of the samples for both concentration show the Schottky-type anomaly around 30 K. This is originated from the crystal electric field (CEF) splitting of the 4f states with the first excited level Δ 1 and the second excited level Δ 2 from the ground state. The obtained values of these ( Δ 1 / k B = 78 K and Δ 2 / k B = 143 K ) on x = 0.02 are larger than the values on x = 0 (60 and 130 K). The enhancement of the CEF splitting of the 4f states might result from the chemical compression due to substitution of small amount of the Ni ion for the Cu ion.

The porous poly(vinyl alcohol) (PVA)–poly(vinyl acetate) (PVAc) composite film prepared by acetone extraction from a PVAc latex film containing PVA was colored in organic solvents for PVAc having a refractive index close to that of PVA. The scattered color changed from yellow to green through orange, red, purple, and blue with an increase in the refractive index of the solvents. The coloration phenomena were based on the intersection between the dispersive curve of PVA and that of the solvents for PVAc in the visible region. If a mixed organic solvent of a solvent and a nonsolvent for PVAc was used, the porous film easily exhibited a color change when it was placed between two glass plates which were pressed together using paper clips. When the refractive index of the solvent was higher than that of the nonsolvent, the scattered color changed from yellow to blue with increasing pressure, and when the refractive index of the solvent was lower than that of the nonsolvent, the scattered color conversely changed from blue to yellow. This mechanism was found to involve a very simple phenomenon in which PVAc grafted on the surfaces of the spherical PVA cells selectively absorbs the solvent from the mixed solvent, and the nonsolvent remaining in the PVA cells is forced out of the porous film with increasing pressure. This piezochromism can be controlled by the refractive index of the mixed solvent, the selection of the solvent and the nonsolvent for PVAc, and the pressure gradient.

Multidrug resistance protein 2 (MRP2, ABCC2) is localized to the apical membrane of hepatocytes and played an important role in the biliary excretion of a broad range of endogenous and xenobiotic compounds and drugs, such as pravastatin. However, the effects of statins on MRP2 in the liver and the precise mechanisms of their actions have been obscure. The goal of this study was to determine the regulatory molecular mechanism for statin-induced MRP2 expression in hepatocytes. In vitro and in vivo studies suggested that pitavastatin increased MRP2 expression. Pitavastatin promoted liver X receptor (LXR) alpha/beta translocation from the cytosol to nuclei, resulting in LXR activation. Deletion and mutational analysis suggested that the potential sterol regulatory element (SRE) played a major role in the observed modulation of MRP2 expression by pitavastatin. Furthermore pitavastatin increased the protein-DNA complex, and when SRE was mutated, stimulation of the protein-DNA complex by pitavastatin was decreased. It was demonstrated that pitavastatin upregulated MRP2 expression by an SREBP regulatory pathway in hepatocytes and that the actions of statins may lead to improve the biliary excretion of MRP2 substrates. (C) 2013 Elsevier B.V. All rights reserved.

The coloration phenomena of porous poly(vinyl alcohol) (PVA)-poly(vinyl acetate) (PVAc) composite films in organic solvents, which were prepared from dried PVAc latex films containing PVA as a protective colloid with acetone extraction, have been investigated from the standpoint of light dispersive power. When the white opaque porous films were dipped in organic solvents having a refractive index near that of PVA, they became so transparent that one could read letters under the films. If solvents having a high light dispersive power such as aromatic compounds were used, the porous films became markedly colored. The color of the scattered light, which was complementary to that of the transmitted light, did not change with the observing direction vs the irradiating direction of the white light and shifted from yellow to green through orange, red, violet, and blue as the refractive index of the solvents increased. This was evident from the fact that the intersection of the dispersion curves of PVA had a low light dispersive power and solvents had a high light dispersive power. The coloration of the porous PVA-PVAc composite films in the solvents showed reversible thermochromism. The residual grafted or highly branched PVAc in the spherical cells of PVA after acetone extraction played an important role in the penetration of solvents into the inner parts of the porous films and in the refractive index of the PVAc swollen by the solutions in the porous films.

We have carried out the specific heat measurements under pressures between 0 and 0.91 GPa on CeMg2Cu9, in which the Ce atoms are a two-dimensional arrangement. A large peak is observed at T N =2.5 K for 0 GPa . TN increases below 0.89 GPa , and turns to decrease with pressurization. The released magnetic entropy Sm below TN is about 60% of R ln 2 expected for the twofold spin degeneracy, suggesting Kondo-compensated moments are formed in the low-temperature range.