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(NH4)2Sr treatment was employed to enhance the efficiency of AIGaN metal-insulator-semiconductor (MIS) photodetectors (PDs) with a liquid phase deposited (LPD) SiO2 layer. With (NH4)2Sr treatment, one can reduce the reverse leakage current of the PD by 2 orders of magnitude and enhance the effective Schottky barrier height from 0.77 to 0.86 eV. Also, the (NH4)2Sx. treatment can also significantly reduce the interface state density, Dit at the AIGaN/LPD oxide interface. Photo-to-dark current ratio observed from the PDs with (NH4)2Sx treatment was also significantly larger. [ABSTRACT FROM AUTHOR]

An Er3+:Bi2(MoO4)3 single crystal has been grown by the Czochralski technique. The Stark sublevels of the 4I15/2 and 4I13/2 multiplets of Er3+ ions in the crystal were determined. The polarized absorption spectra, polarized fluorescence spectra, and fluorescence decay curve of the crystal were measured at room temperature and the relevant spectroscopic parameters, including the Judd–Ofelt intensity parameters, spontaneous emission probability, fluorescence branching ratio, radiative lifetime, and stimulated emission cross section, were estimated. The effect of re-absorption on the spectroscopic parameters was discussed. When the crystal was excited at 977 nm, up-conversion green fluorescence was observed and discussed. [ABSTRACT FROM AUTHOR]

Polarized spectral properties of Er3+:NaGd(WO4)2 single crystal are reported. The crystal was grown by the Czochralski method. The Judd–Ofelt theory was applied to analyze the polarized absorption spectra and then calculate the spontaneous emission probabilities, radiative lifetimes, and branching ratios. Fluorescence decay curves of the 4 I 13/2, 4 I 11/2, and 4 S 3/2 multiplets for the Er3+ ions were measured. Stimulated emission cross-sections of the 4 I 13/2→4 I 15/2 transition obtained by the Fuchtbauer–Ladenberg formula and the reciprocity method were compared. Multi-phonon relaxation rates of the crystal were estimated. Green up-conversion fluorescence around 531 and 552 nm was observed, and the possible up-conversion mechanisms were proposed. [ABSTRACT FROM AUTHOR]

The immune system is a complex network that regulates and maintains the host's defense system. Changes and alterations in the immune system precipitate a series of reactions to prevent further damage as well as initiate repair. The system's cellular component relies on cytokines (interleukins, tumor necrosis factor, interferons, etc.) to facilitate communication in response to a foreign antigen. Cytokine concentrations are therefore elevated during times of inflammation, such as rejection of a transplanted organ. Recent research suggests that interleukin-6 may have an inhibitory effect on cytochrome P-450 3A and thus affect drug metabolism. Cyclosporine, which is administered to prevent rejection of transplanted organs, is metabolized primarily by the P-450 3A system. Thus, the inhibitory effect of interleukin-6 may alter cyclosporine concentrations, which in turn may increase its adverse effects, such as nephrotoxicity.