Bioaerosol detection over Athens, Greece using the laser induced fluorescence technique

The challenge in today's bioaerosol monitoring is to retrieve real-time information on the qualitative and quantitative composition of the ambient air in bioparticles implicated to human health. A pilot study was conducted during March-May 2018 in Athens, Greece in order to detect bioparticles within the Planetary Boundary Layer (PBL) by implementing the LIF LiDAR (Laser-Induced Fluorescence Light Detection and Ranging) technique at an excitation wavelength of 266 nm in order to determine the major components' contribution on the total fluorescence LiDAR signals aloft (30-100 m above our site). The laboratory characterization of the prevalent pollen grains and fungal spores fluorescence signatures enabled through deconvolution the breaking down of the retrieved LIF LiDAR signals and unravelled each bioparticle's contribution. The bioaerosol occurrence and concentration, as determined by the concurrent sampling with a volumetric particle sampler, verified that the detected fluorescence is related to the fungal and pollen aerosol concentration. The results of this study are very promising for the implementation of remote sensing technology in routine detection and quantification of airborne bioparticles in real-time which is important for allergy sufferers and physicians.

"CLASPing" tungsten's effects on microtubules with "PINs"

Tungsten, supplied as sodium tungstate, inhibits root elongation in Arabidopsis thaliana, which has been attributed to a diminishing of PIN2 and PIN3 auxin efflux carriers. In this work, we sought to analyze the effect of tungsten on cortical microtubules and CLASP (Cytoplasmic Linker Associated Protein), which are also involved in the anisotropic cell expansion of root cells. Seedlings grown in a tungsten-free substrate for 4 d and then transplanted into a tungsten-containing substrate exhibited randomly oriented microtubules in a time-dependent manner. While tungsten had no effect on roots treated for 3 h, microtubule alignment was obviously affected in the transition and elongation zones after a 6, 12, 24, 48 h tungsten treatment, at prolonged tungsten administrations and in seedlings grown directly in the presence of tungsten. This change in microtubule orientation may be associated with the reduction of CLASP protein expression induced by tungsten, as evidenced in experiments with plants expressing the CLASP-GFP protein. A possible mechanism, by which the coordinated functions of CLASP, PIN2 and microtubules are affected, as revealed by inhibited root growth, is discussed.