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In this article, we present a versatile gas detector that can operate on an unmanned aerial vehicle (UAV) or unmanned ground vehicle (UGV). The device has six electrochemical modules, which can be selected to measure specific gases, according to the mission requirements. The gas intake is realized by a miniaturized vacuum pump, which provides immediate gas distribution to the sensors and improves a fast response. The measurement data are sent wirelessly to the operator’s computer, which continuously stores results and presents them in real time. The 2 m tubing allows measurements to be taken in places that are not directly accessible to the UGV or the UAV. While UAVs significantly enhanced the versatility of sensing applications, point gas detection is challenging due to the downwash effect and gas dilution produced by the rotors. In our work, we demonstrated the method of downwash effect reduction at aerial point gas measurements by applying a long-distance probe, which was kept between the UAV and the examined object. Moreover, we developed a safety connection protecting the UAV and sensor in case of accidental jamming of the tubing inside the examined cavity. The methods presented provide an effective gas metering strategy using UAVs.

Novichok-like or fourth-generation agents (FGAs) are chemical warfare agents (CWAs) which have been gaining attention since their use in assassination attempts on Sergei Skripal and Alexei Navalny. Due to their physicochemical properties, these substances are difficult to detect by implemented technologies, resulting in massive response efforts if their occurrence is suspected in a civilian environment. In this work, an approach is presented that uses handheld forensic light sources to visually detect surfaces contaminated with Novichok. More than 100 different wavelength combinations were applied to seven substances chosen to represent the newly listed schedule 1 subgroups in the Annex on Chemicals of the Chemical Weapons Convention. One waveband was identified as promising, which allowed the optical detection of all tested substances. Several surfaces, which could be affected in case of a possible attack using novichok-like nerve agents, were also successfully evaluated. The proposed procedure could be implemented for CBRN responders and security agencies to significantly reduce response efforts, thereby diminishing the overall threat posed by this group of chemicals (FGAs). This procedure was also extended to carbamates and CWAs.

As common industrial by-products, airborne engineered nanomaterials are considered important environmental toxicants to monitor due to their potential health risks to humans and animals. The main uptake routes of airborne nanoparticles are nasal and/or oral inhalation, which are known to enable the transfer of nanomaterials into the blood stream resulting in rapid distribution in the body. Consequently, mucosal barriers present in nose, buccal and lung have been identified and intensively studied as the key tissue barrier to nanoparticle translocation. Despite decades of research, surprisingly little is known about the differences among various mucosa tissue types to tolerate nanoparticle exposures. One limitation in comparing nanotoxicological data sets can be linked to a lack of harmonization and standardization of cell-based assays, where a) different cultivation conditions such as air-liquid interface or submerged cultures, b) varying barrier maturity and c) diverse media substitutes have been used. The current comparative nanotoxicological study therefore aims at analyzing the toxic effects of nanomaterials on four human mucosa barrier models including nasal (RPMI2650), buccal (TR146), alveolar (A549), and bronchial (Calu-3) mucosal cell lines to better understand the modulating effects of tissue maturity, cultivation conditions and tissue type using standard Transwell cultivations at liquid-liquid and air-liquid interfaces. Overall, cell size, confluency, tight junction localization, and cell viability as well as barrier formation using 50% and 100% confluency was monitored using trans-epithelial-electrical resistance (TEER) measurements and Presto Blue assays of immature (e.g. 5 days) and mature (e.g. 22 days) cultures in the presence and absence of corticosteroids such as hydrocortisone. Results of our study show that cellular responses to increasing nanoparticle exposures are highly cell type specific, where bronchial mucosal cell barriers models cultivated under ALI conditions showed less tolerance to acute ZnO nanoparticle exposures. Additionally, stronger toxicities are found using early mucosa barriers compared to later barrier models being maturated under air-liquid cultivation conditions.