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An organic–inorganic compound was prepared by adding organic material to inorganic, semiconductor nanoparticles. Polyethylene glycol, tethered chains (PEG-TC) were added to the surface of CdS nanoparticles by a colloidal technique. The photoluminescence (PL) peak energy of the CdS nanoparticles gradually increased with the solvent density. Furthermore, by combining texas red streptavidin molecules with the PEG-TC on the surface of the CdS nanoparticles, the emission from texas red and change in the PL peak energy of CdS nanoparticle was observed. These results indicate that the recombination processes of the CdS nanoparticles can be controlled by the physical state of the PEG-TC chain. [Copyright &y& Elsevier]

We prepared novel CdS nanocrystal by colloid technique; CdS nanocrystal possessing polyethylene glycol tethered chains (PEG-TC) on the surface. A relatively sharp optical absorption peak was observed at around 3.4 eV. The size of the nanocrystal was estimated by the peak energy to be 4–5 nm in diameter. A very broad photoluminescence (PL) peak centered at 2.4 eV was observed when excited at 3.8 eV. The PL spectra excited at lower photon energy indicates that the PL peak is composed of 2.5, 2.3 and 1.7–1.8 eV peaks. When we excited the specimen below 2.7 eV, PL spectra of colloid solution and cast film of PEG-TC CdS was very different. The difference in the recombination processes between PEG-TC CdS ensemble and isolated PEG-TC CdS is discussed in the present paper. [Copyright &y& Elsevier]

We investigated the dependence of perpendicular magnetic anisotropy in CoFeB-MgO on the MgO layer thickness. Magnetization curves show that a clear perpendicular magnetic easy axis is obtainable in a 1.5-nm thick CoFeB layer by depositing MgO of more than three monolayers. We investigated anisotropy in CoFeB-MgO deposited on four different buffer layers. Results show that a counter interface of CoFeB-nonmagnetic metal affects the perpendicular anisotropy of CoFeB/MgO. [ABSTRACT FROM AUTHOR]

We have investigated a tunnel magnetoresistance (TMR) ratio of CoFeB/MgO perpendicular magnetic tunnel junctions (p-MTJs) with a 40 nm diameter as a function of an annealing temperature Ta. The TMR ratio at room temperature (RT) increases with increasing Ta and reaches 149% at Ta = 350 °C, and further increase of Ta results in a strong reduction of the TMR ratio, i.e., 2% at Ta = 400 °C. The temperature dependence of the junction resistance versus magnetic field loops reveals that the reduced TMR ratio at RT is due to the disappearance of a stable antiparallel magnetization configuration. We find that reduction of dipole coupling restores the TMR ratio. [ABSTRACT FROM AUTHOR]

Junction size dependence of critical current (IC0) for spin transfer torque switching and thermal stability factor (E/kBT) was examined in CoFeB/MgO perpendicular magnetic tunnel junctions (p-MTJs). The IC0 increased with increasing recording layer area (Srec). On the other hand, the E/kBT showed almost constant values even though the Srec was increased from ∼1500 nm2 (44 nmφ) to ∼5000 nm2 (76 nmφ). Both IC0 and E/kBT behavior can be explained with assuming that the nucleation type magnetization reversal takes place in CoFeB/MgO p-MTJs. [ABSTRACT FROM AUTHOR]

We successfully treated three cases of adult Still's disease (ASD) with dexamethasone. High dose prednisolone, which was initially used to treat these patients, failed to remit the disease in all cases. Although they were resistant to prednisolone, all these patients had remarkable improvements in clinical and laboratory findings after switching to an equivalent dose of dexamethasone. We propose using dexamethasone as an alternative for treating ASD before adding immunosuppressants or disease modifying anti-rheumatic drugs (DMARD), when prednisolone therapy does not suppress disease activity sufficiently. [ABSTRACT FROM AUTHOR]