Average capacity optimization in free-space optical communication system over atmospheric turbulence channels with pointing errors.

A model is proposed to study the average capacity optimization in free-space optical (FSO) channels, accounting for effects of atmospheric turbulence and pointing errors. For a given transmitter laser power, it is shown that both transmitter beam divergence angle and beam waist can be tuned to maximize the average capacity. Meanwhile, their optimum values strongly depend on the jitter and operation wavelength.

[ICCD-based fast fluorescence micro-imaging technique and preliminary application in living cells].

A fast fluorescence micro-imaging system using mainly intensified charge couple device (ICCD), argon-ion laser, and xenon lamp was set up, and its preliminary application in living cells was presented. Real-time observation and imaging of fast concentration and distribution changing of intracellular Ca2+ labeled by Fluo-3, a fluorescent Ca2+ indicator, in the proliferation process of rat cerebral micro-vessels endothelial cells (rCMECs) were carried out, and curves of artificial intensity versus imaging sequence of four typical points were obtained. It is shown that the ICCD-based fast fluorescence micro-imaging system is a powerful tool for recording the real-time fast processes in living cells.

[Study on multi-photon excited fluorescence combined with capillary electrophoresis].

This paper describes a new method, multiphoton excitation fluorescence detection combined with capillary electrophoresis separation. The excitation source was a self mode-locked femtosecond titanium-sapphire laser (Spectra-physics Inc.), producing a stream of pulses with a pulse duration of about 100 fs at 82 MHz repetition rate.