Understanding autism spectrum disorders with animal models: applications, insights, and perspectives.

Autism spectrum disorder (ASD) is typically characterized by common deficits in social skills and repetitive/stereotyped behaviors. It is widely accepted that genetic and environmental factors solely or in combination cause ASD. However, the underlying pathogenic mechanism is unclear due to its highly heterogeneous nature.

[Wavelength conversion and spectral analysis in periodically polarized lithium niobate waveguide].

Wavelength conversion exploiting cascaded second harmonic and difference frequency generation (c(SHG/DFG)) in periodically polarized LiNbO3 (PPLN) waveguides was experimentally researched. While wavelength converter was pumped with a pulsed wave, the pump pulse can be used to carry the information and wavelength conversion occurs between the pump wave and converted wave, thus wavelength conversion transferring the information from the pump wave to the converted waves includes two processes of second order nonlinear reaction: the first wavelength conversion from pump wave to SH wave occurs with SHG process, and the second wavelength conversion from SH wave to converted wave occurs with DFG process. In the first process the group velocities mismatching (GVM) for pulses at different wavelengths due to material property load the temporal walk-off between pump pulse and SH pulse located in the 1.