ABSTRACT
We have evaluated the influence of growth media and washing on the laser-induced fluorescence spectra of bacteria. Three different bacterial simulants were cultured in three types of growth media. Three kinds of samples were generated from each culture: the culture itself, the growth medium alone, and a triple-washed sample. The materials were injected as aerosols in a lab-sized lidar aerosol chamber to obtain their spectra. Using two different analysis approaches, signature variations were observed between the three kinds of samples for most combinations of growth media/bacteria. This study concludes that the culture media used influences the spectral signatures.
Subject(s)
Aerosols/chemistry , Culture Media, Conditioned/chemistry , Spectrometry, Fluorescence/methods , Bacillus/chemistry , Bacillus/metabolism , Biological Warfare Agents , Erwinia/chemistry , Erwinia/metabolism , Pattern Recognition, Automated/methods , Principal Component AnalysisABSTRACT
It is demonstrated that with a proper choice of embedding material, the composite beam bending method constitutes an effective and reliable approach for tuning fiber Bragg gratings. A long-term stable device is presented with a dynamic range of 80 nm, which exhibits insertion losses smaller than 0.28 dB and small variations of the full width at half-maximum.