Guanidinium 5,5'-Azotetrazolate: A Colorful Chameleon for Halogen-Free Smoke Signals.

A progressive halogen-free multicolored smoke system to obtain white, red, violet, yellow, green, and blue smoke color is presented. The nitrogen-rich salt guanidinium 5,5'-azotetrazolate (GZT), which is usually applied as a gas generator or propellant ingredient, was combined with different smoke dyes (Solvent Red 1, Solvent Violet 47, Solvent Green 3, Solvent Yellow 33). These two-component smoke mixtures offer a convenient and safe multicolor approach without the need for potassium chlorate or any other hazardous material.

Backward supercontinuum emission from a filament generated by ultrashort laser pulses in air.

Backward emission of the supercontinuum from a light filament induced by high-intensity femtosecond laser pulses propagating in air has been observed to be enhanced compared with linear Rayleigh-Mie scattering. This enhancement is interpreted as a nonlinear scattering process onto longitudinal refractive-index changes induced by the laser pulse itself. The spectral dependence of the supercontinuum angular distribution is also investigated.

Outbreak of nosocomial Burkholderia cepacia infection and colonization associated with intrinsically contaminated mouthwash.

From August 1996 through June 1998, 69 ventilated, intensive care unit patients at two Arizona hospitals had nosocomial respiratory tract cultures positive for Burkholderia cepacia. Intrinsically contaminated alcohol-free mouthwash was identified by pulsed-field gel electrophoresis as the source of the outbreak.

Characterization of a circulating antigen involved in immune complexes in visceral leishmaniasis patients.

Complications of visceral leishmaniasis are explained in part by immune complex pathology, particularly nephritis. Using the polyethylene glycol precipitation method, we identified among these complexes a Leishmania infantum circulating antigen by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. Monoclonal antibodies were produced to specifically detect this antigen.