Biomonitoring for wide area surveying in landmine detection using honeybees and optical sensing

This project has received funding from NATO Science for Peace & Security under grant agreement MYP G5355, and the Engineering and Physical Sciences Research Council under EP/K503940/1.Humanitarian demining is a worldwide effort and the range of climates and environments prevent any one detection method being suitable for all sites, so more tools are required for safe and efficient explosives sensing. Landmines emit a chemical flux over time, and honeybees can collect the trace residues of explosives (as particles or as vapour) on their body hairs. This capability was exploited using a passive method allowing the honeybees to freely forage in a mined area, where trace explosives present in the environment stuck to the honeybee body, which were subsequently transferred onto an adsorbent material for analysis by a fluorescent polymer sensor. Potential false positive sources were investigated, namely common bee pheromones, the anti-varroa pesticide Amitraz, and the environment around a clean apiary, and no significant response was found to any from the sensor. The mined site gave a substantial response in the optical sensor films, with quenching efficiencies of up to 38%. A model was adapted to estimate the mass of explosives returned to the colony, which may be useful for estimating the number of mines in a given area.PostprintPeer reviewe

Physicochemical Properties, Cytotoxicity, and Antioxidative Activity of Natural Deep Eutectic Solvents Containing Organic Acid

Natural deep eutectic solvents (NADES) may be considered ‘designer solvents’ due to their numerous structural variations and the possibility of tailoring their physicochemical properties. Prior to their industrial application, characterization of NADES is essential, including determination of their physicochemical properties, cytotoxicity, and antioxidative activity. The most important physicochemical properties of eight prepared NADES (choline chloride:malic acid, proline:malic acid, choline chloride:proline:malic acid, betaine:malic acid, malic acid:glucose, malic acid:glucose:glycerol, choline chloride:citric acid, and betaine:citric acid) were measured as functions of temperature and water content. In general, the structure of prepared NADES greatly influences their physical properties, which could be successfully modified and adjusted by addition of water. All tested NADES were absolutely benign and noncorrosive for investigated steel X6CrNiTi18-10. Furthermore, cytotoxicity of prepared solvents was assessed toward three human cell lines (HEK-293T, HeLa, and MCF-7 cells), and antioxidative activity was measured by the Oxygen Radical Absorbance Capacity (ORAC) method. With regard to cell viability, all tested NADES containing carboxylic acid could be classified as practically harmless and considered environmentally safe. The ORAC values indicated that the tested NADES displayed antioxidative activity

Renewable Energy - Wind Turbines, Solar Cells, Small Hydroelectric Plants, Biomass, and Geothermal sources of energy

Renewable Energy - Wind Turbines, Solar Cells, Small Hydroelectric Plants, Biomass, and Geothermal sources of energy, New Functional Materials and Hight Technologies, Tivat, Montenegr

Effect of herbicides on microbiological properties of soil

Microorganisms decompose herbicides and they may serve as bioindicators of soil changes following herbicide application. Certain microbial species may be used as bioherbicides. This study has shown that Azotobacter is most sensitive to herbicide application; it is, therefore, a reliable indicator of the biological value of soil. The numbers of this group of nitrogen-fixing bacteria decrease considerably in the period of 7-14 days after herbicide application. Simultaneously, the numbers of Actinomycetes and less so of fungi increase, indicating that these microorganisms use herbicides as sources of biogenous elements. Rate of herbicidal decomposition depends on the properties of the preparation applied herbicide dose as well as on the physical and chemical soil properties, soil moisture and temperature, ground cover, agrotechnical measures applied and the resident microbial population

Textile-based wearable device for detection of date rape drugs in drinks

In this article, a sensing element for detection of date rape drugs in drinks is presented. The element consists of a three-dimensional printed holder, in which two embroidered electrodes have been fixed, forming a capacitive structure. As the dielectric properties of the liquid between these electrodes’ changes, the capacitance and consequently the impedance are changed. For experimental purposes, diazepam, a model rape drug, sucrose, and sodium chloride, which are used as control ingredients, were dissolved in a 40% V/V alcoholic beverage, serving as solutions for testing and comparison. The selectivity, repeatability, and sensitivity of the proposed sensor were tested. The sensitivity of detection of 1 mg/ml of diazepam in drinks was 0.92628 Ωl/mg, sucrose was 0.94774 Ωl/mg and sodium chloride was 2.46867 Ωl/mg, at 1 MHz. Moreover, with the use of the Cole impedance model, the selectivity of the sensor in the detection of diazepam, through the Nyquist plot and parameter estimation, has been achieved. Sensor repeatability was calculated through the relative standard deviation with the result for 1 mg/ml of diazepam dissolved in alcohol on 1 MHz being 2.48, in terms of impedance modulus. The presented sensor platform can successfully detect drugs in drinks and can protect from many cases of such assaults in a real world

Multiple proviral integration events after virological synapse-mediated HIV-1 spread

HIV-1 can move directly between T cells via virological synapses (VS). Although aspects of the molecular and cellular mechanisms underlying this mode of spread have been elucidated, the outcomes for infection of the target cell remain incompletely understood. We set out to determine whether HIV-1 transfer via VS results in productive, high-multiplicity HIV-1 infection. We found that HIV-1 cell-to-cell spread resulted in nuclear import of multiple proviruses into target cells as seen by fluorescence in-situ hybridization. Proviral integration into the target cell genome was significantly higher than that seen in a cell-free infection system, and consequent de novo viral DNA and RNA production in the target cell detected by quantitative PCR increased over time. Our data show efficient proviral integration across VS, implying the probability of multiple integration events in target cells that drive productive T cell infection