Post-compression of powerful femtosecond pulses after second harmonic generation.

A proof-of-principle experiment of highly efficient (38%) second harmonic generation was implemented at a ∼1T W/c m 2 intensity of a 45 fs pulse in a composite nonlinear sample-a 1 mm KDP crystal glued onto a 1 mm fused silica substrate. The attenuated replica of the second harmonic pulse (455 nm) was compressed down to 28.6 fs by means of dispersive mirrors, with a significant reduction in both the wings and the far temporal contrast. The peak power of the second harmonic was ∼74% of the power of the fundamental harmonic, which ensured a three-fold increase in the focal intensity.

[Number of malarial mosquitoes and their feeding hosts under urban and rural conditions]. / Chislennost' maliariinykh komarov i ikh prokormitelei v gorodskikh i sel'skikh usloviiakh.

In connection with building of hydrotechnical constructions and creation of water bodies the abundance of anopheles as in urban so in rural conditions was high that amounted to 120 to 690 females per a site of day's rest. By means of precipitation reaction in the capillaries with an extraction of stomachs' contents it has been established that in rural conditions hosts of anopheles are horned cattle while in urban ones--man and poultry.