The evolution of chemotaxis assays from static models to physiologically relevant platforms.

The role of chemotactic gradients in the immunological response is an area which elicits a lot of attention due to its impact on the outcome of the inflammatory process. Consequently there are numerous standard in vitro designs which attempt to mimic chemotactic gradients, albeit in static conditions, and with no control over the concentration of the chemokine gradient. In recent times the design of the standard chemotaxis assay has incorporated modern microfluidic platforms, computer controlled flow devices and cell tracking software.

Laser ablation threshold dependence on pulse duration for fused silica and corneal tissues: experiments and modeling.

The surface ablation threshold fluence of fused silica and two porcine cornea layers, the epithelium and the stroma, is characterized as a function of the laser pulse duration in the range of 100 fs-5 ps for a wavelength of 800 nm (Ti:sapphire laser system). The plateaulike region observed between 100 fs and 1 ps for the corneal layers indicates that for use in laser surgery, laser pulse durations chosen within this range should be practically equivalent. Our model predicts that the ablation threshold will decrease rapidly for pulse durations in the low end of the femtosecond regime.