Vertically well-aligned ZnO nanowire ultraviolet ͑UV͒ photodetectors were fabricated by spin-on-glass technology on ZnO:Ga/glass templates. With 2 V applied bias, it was found that dark current density of the fabricated device was only 2.0ϫ 10 −7 A/cm 2 . It was also found that UV-to-visible rejection ratio and quantum efficiency of the fabricated ZnO nanowire photodetectors were more than 1000 and 12.6%, respectively.

A series of naturally occurring cardenolides that exhibit potent anti-transmissible gastroenteritis virus (TGEV) activity in swine testicular (ST) cells has been identified. In an immunofluorescence assay, these cardenolides were found to diminish the expressions of TGEV nucleocapsid and spike protein, which was used as an indication for viral replication; block TGEV infection induced apoptosis and cytopathic effects; and impart the same trend of inhibitory activity against Na/K-ATPase as for anti-TGEV activity. The viral titer inhibition was found to take place in a dose-dependent manner. Knocking down expression of Na/K-ATPase, the cellular receptor of cardenolides, in ST cells was found to significantly impair the susceptibility of ST cells to TGEV infectivity. Thus, we have identified Na/K-ATPase as an anti-viral drug target and its antagonists, cardenolides, a novel class of anti- TGEV agents.

Eigenvalue equations for solving full-vector modes of optical waveguides are formulated using Yee-mesh-based finite difference algorithms and incorporated with perfectly matched layer absorbing boundary conditions. The established method is thus able to calculate the complex propagation constants and the confinement losses of leaky waveguide modes. Proper matching of dielectric interface conditions through the Taylor series expansion of the fields is adopted in the formulation to achieve high numerical accuracy. The method is applied to the study of the holey fiber with triangular lattice, the two-core holey fiber, and the air-guiding photonic crystal fiber.

A SiO2/SiOx/SiO2 strip-loaded waveguide with buried Si quantum dots is optically pumped to provide amplified spontaneous emission centered at 805 nm with spectral linewidth of 140 nm. By top-pumping the 350-nm-thick SiOx with He–Cd laser of 40 mW at 325 nm, the optical gain of 65 cm−1 and loss coefficient of 5 cm−1 are determined. Under a 785 nm small-signal injection diagnosis, the power-dependent gain curve fitting with gain-saturated amplifier model reveals a peak gain of 27 dB (not including waveguide loss) and a net power gain of 9.5 dB for the Si-rich SiOx waveguide amplifier with a length of 5 mm.

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