Synaptic targets of photoreceptors specialized to detect color and skylight polarization in Drosophila

Color and polarization provide complementary information about the world and are detected by specialized photoreceptors. However, the downstream neural circuits that process these distinct modalities are incompletely understood in any animal. Using electron microscopy, we have systematically reconstructed the synaptic targets of the photoreceptors specialized to detect color and skylight polarization in Drosophila, and we have used light microscopy to confirm many of our findings. We identified known and novel downstream targets that are selective for different wavelengths or polarized light, and followed their projections to other areas in the optic lobes and the central brain. Our results revealed many synapses along the photoreceptor axons between brain regions, new pathways in the optic lobes, and spatially segregated projections to central brain regions. Strikingly, photoreceptors in the polarization-sensitive dorsal rim area target fewer cell types, and lack strong connections to the lobula, a neuropil involved in color processing. Our reconstruction identifies shared wiring and modality-specific specializations for color and polarization vision, and provides a comprehensive view of the first steps of the pathways processing color and polarized light inputs

Small molecule specifically inhibiting microglial nitric oxide release could become a potential treatment for neuroinflammation

Microglia are the immune effector cells of the central nervous system (CNS) and react to pathologic events with a complex process including the release of nitric oxide (NO). NO is a free radical, which is toxic for all cells at high concentrations. To target an exaggerated NO release, we tested a library of 16 544 chemical compounds for their effect on lipopolysaccharide (LPS)-induced NO release in cell line and primary neonatal microglia. We identified a compound (C1) which significantly reduced NO release in a dose-dependent manner, with a low IC50 (252 nM) and no toxic side effects in vitro or in vivo. Target finding strategies such as in silico modelling and mass spectroscopy hint towards a direct interaction between C1 and the nitric oxide synthase making C1 a great candidate for specific intra-cellular interaction with the NO producing machinery

Electric fields in kHz-driven plasma jets

Non-thermal atmospheric pressure plasma jets have been developed for use on thermosensitive targets at atmospheric pressure, for example polymers or for biomedical applications. Diagnostics on these plasma sources is challenging because of their transient nature, often associated jitter and very small volume. Electric fields, fundamental property essential for the understanding of the discharge, are not well known. In this talk two methods of electric field measurements will be shown applied to a He kHz-driven jet, one based on spectroscopy and one on polarimetry and the obtained results will be discussed

Electric field measurements in atmospheric pressure plasmas

Low temperature plasmas at atmospheric pressure offers possibilities that were not accessible to plasma-based technologies for a long time, such as usage on materials sensitive to high temperatures, (bio)materials that are not resistant to vacuuming or even fully drying, (bio)targets that are sensitive to significant current transfer. In addition to the simplicity with which the plasma sources can be built and the ease with which they can be operated, lot temperature plasmas have become very popular in the recent years. A great number of scientific publications has followed this rise in interest for atmospheric pressure plasmas, covering different geometries of mostly dielectric barrier discharges (DBDs), used with or without gas flow and a wide range of excitation frequencies from Hz to MHz. Most commonly reports address the discharge dynamics, densities of heavy species, at times gas temperature measurements, imaging of flow fields and rarely electron densities and electric field but very few on electric field measurements. This paper will give an overview of the recent work in the electric field measurements in atmospheric pressure plasma jets that operate in the ’bullet mode’. A Helium jet with flow rates up to 2 SLM, in a low-power mode (up to 1 W dissipated in the discharge). The jet is run in the bullet mode where one plasma bullet is emitted per voltage period. The results fill focus on the comparison between the jets driven by 30 kHz sine voltage and jets driven by short high voltage pulses. Two measurement methods have been used that allow for comparison between the electric field in the gas phase and on the treated targets, which vary from dielectrics to liquids