Fig. 1. 266-nm-excited fluorescence spectra of common fluorophores found in biological particles^[39]

Fig. 2. Excitation-emission matrix of fluorophores. (a) Tryptophan; (b) Reduced coenzyme I(NADH)^[59]

Fig. 3. Geographic distribution map of relevant research institutions. This map is based on the map provided by the Standard Map Service, review number GS(2020)4388, with the northern hemisphere portion intercepted. The dots on the map indicate the approximate geographic locations of the relevant research institutions, and the data used were obtained from the Bing Maps service provided by Microsoft Corporation

Fig. 4. Fluorescence spectrum of ovalbumin (OV, purple dashed line) and spectrum from the OV spectral library (purple solid line) were measured by lidar at 2.5 km at midday, and the cross in the inset is the lidar field of view pointing to the white bioaerosols cloud ^[50]

Fig. 5. Total normalized spectra S^T(square) derived by the lidar using accumulated photons in 1.5–2.0 km altitude range, decomposed normalized spectral components of fluorescence spectra S^F(circle) and water vapor Raman spectra S^V(hexagon) ^[99]

Fig. 6. Fluorescence spectra of Jpn. Cedar pollen in air (solid line) detected by the LIFS lidar and fluorescence spectrum in the spectral library (dashed line), inset shows the experimental site^[53]

Fig. 7. The Defense Research and Development Canada (DRDC) has developed the BioSense system^[113]

Fig. 8. Normalized LIF spectra of different bacterial samples excited at two wavelengths. (a) Excitation at 355 nm; (b) Excitation at 280 nm^[51]