One primary mechanism for bacteria developing resistance is frequent exposure to antibiotics. Nanoantibiotics (nAbts) is one of the strategies being explored to counteract the surge of antibiotic resistant bacteria. nAbts are antibiotic molecules encapsulated with engineered nanoparticles (NPs) or artificially synthesized pure antibiotics with a size range of ≤100 nm in at least one dimension. NPs may restore drug efficacy because of their nanoscale functionalities. As carriers and delivery agents, nAbts can reach target sites inside a bacterium by crossing the cell membrane, interfering with cellular components, and damaging metabolic machinery. Nanoscale systems deliver antibiotics at enormous particle number concentrations. The unique size-, shape-, and composition-related properties of nAbts pose multiple simultaneous assaults on bacteria. Resistance of bacteria toward diverse nanoscale conjugates is considerably slower because NPs generate non-biological adverse effects. NPs physically break down bacteria and interfere with critical molecules used in bacterial processes. Genetic mutations from abiotic assault exerted by nAbts are less probable. This paper discusses how to exploit the fundamental physical and chemical properties of NPs to restore the efficacy of conventional antibiotics. We first described the concept of nAbts and explained their importance. We then summarized the critical physicochemical properties of nAbts that can be utilized in manufacturing and designing various nAbts types. nAbts epitomize a potential Trojan horse strategy to circumvent antibiotic resistance mechanisms. The availability of diverse types and multiple targets of nAbts is increasing due to advances in nanotechnology. Studying nanoscale functions and properties may provide an understanding in preventing future outbreaks caused by antibiotic resistance and in developing successful nAbts.

Abstract. We present results of a feasibility study that uses Artificial Neural Networks (ANN) for the 10 retrieval of intensive microphysical parameters of atmospheric pollution from combinations of backscatter (β) and extinction coefficients (α) that can be measured with multiwavelength Raman and high-spectral resolution lidar at 355, 532, and 1064 nm. We investigated particle effective radius, and the real and imaginary part of the complex refractive index. ANN could be a useful alternative or supplementary method over the traditional approach of retrieving microphysical particle properties with 15 classical inversion algorithms because data analysis with ANN is significantly faster and allows for investigating the information content of the optical input data. We investigated the data combinations 3β+2α, 3β+1α (355 and or 532 nm), 2β (532, 1064 nm) +1α (532 nm), and 3β with Feedforward Backpropagation Multilayer Perceptron Neural Networks. The synthetic optical data were computed with a Mie-scattering algorithm for monomodal particle size distributions. Mean radii of the size 20 distributions ranged between 0.01 and 0.5 µm, and mode widths ranged between 1.4 and 2.5 resulting in effective radii between 0.13 and 4.1 µm. We tested real parts between 1.2 and 2, and imaginary parts between 0.0i and 0.1i. The complexity of developing the networks did not allow us to test the influence of measurement errors of the optical data but the error produced by the ANN can be quantified. From the five basic data combinations, our current network design allows us to derive effective radius with an 25 accuracy of approximately ±16 to ±35%, and ±17 to ±39% if the true mean radii is in the range from Atmos. Meas. Tech. Discuss., doi:10.5194/amt-2016-7, 2016 Manuscript under review for journal Atmos. Meas. Tech. 2 110 -250 nm, and 260 -500 nm, respectively. The real part can be derived with an accuracy of approximately ±7 to ±10%. We find retrieval errors of approximately ± 31 to ±38% for the imaginary part. We show that ANN can potentially estimate some particle parameters with various levels of uncertainty not only from what we denote as 3β+2α information but also from data combinations of 30 3β+1α (355 or 532), 2β (532, 1064) +1α (532), and 3β. We hypothesize that the ANN carries out first a pre-selections of various values of extinction-based Ångström exponents with regard to effective radius and then uses this information to create the strong correlation between particle effective radius and lidar ratios in all particle size distributions (PSDs) we investigated. 35

In Bangladesh, among the routes of chromium eco-toxicity, feeds and fertilizer production from tanned skin-cut wastes is the most direct one leading to food chain contamination. The tanning industries of Hazaribagh are processing some 220 metric tons of hide a day with an associated release of 600 -1000Kg of tanned skin-cut waste (SCW) resulting from per ton processed hide. The SCW are protein-rich and are unscientifically used to produce protein-concentrates for poultry and fish feeds, and organic fertilizer. In view of the facts, a huge migration of chromium can happen into poultry products, fish and vegetables, and further bio-magnify into food chain. The target population of this phenomenon is also huge. Regional bio-concentration of chromium was investigated in commercially produced chicken eggs. Though the routes of distribution of this hugely produced protein-concentrates from SCW are unknown, eggs were sampled from Dhaka and its nearby other seven districts covering the central region of Bangladesh. Twelve eggs were randomly sampled from each district's egg stock market while albumen and yolk in each egg were studied separately for all studies. Out of the 192 samples from 96 eggs, dry weight basis mean chromium concentration was found to be 1.9016 ppm with a sample standard deviation of 0.1502. The concentration levels were ranged from maximum of 19.8051 ppm to undetectable levels. Single poultry egg was found to contain a mean chromium content of 23.3809 µg, which exceeds adequate daily dietary intake of children up to 8 years of age as well as corresponds to major part for other age groups. The region-wise physical properties of the eggs were also studied which included USDA size grading by whole weight at raw condition, whole weight ratio of raw condition to complete boiled condition, weight ratio of boiled shell-albumen-yolk, moisture content of albumen of boiled eggs, and moisture content of yolk of boiled eggs. The mean whole weights of eggs at raw condition were within the range of 39.9568 g ('peewee' as per USDA size grading) to 62.4047 g ('large' as per USDA size grading), the mean whole weight ratio of raw condition to complete boiled

The COVID-19 pandemic involving SARS-CoV-2 has raised interest in using antimicrobial lipid formulations to inhibit viral entry into their host cells or to inactivate them. Lipids are a part of the innate defense mechanism against pathogens. Here, we evaluated the use of nano-monocaprin (NMC) in inhibiting enveloped (phi6) and unenveloped (MS2) bacteriophages. NMC was prepared using the sonochemistry technique. Size and morphology analysis revealed the formation of ~ 8.4 ± 0.2-nm NMC as measured by dynamic light scattering. We compared the antiviral activity of NMC with molecular monocaprin (MMC) at 0.5 mM and 2 mM concentrations against phi6, which we used as a surrogate for SARS-CoV-2. The synthesized NMC exhibited 50% higher antiviral activity against phi6 than MMC at pH 7 using plaque assay. NMC inactivated phi6 stronger at pH 4 than at pH 7. To determine if NMC is toxic to mammalian cells, we used MTS assay to assess its IC 50 for HPDE and HeLa cell lines, which were ~ 203 and 221 µM, respectively. NMC may be used for prophylactic application either as a drop or spray since many viruses enter the human body through the mucosal lining of the nose, eyes, and lungs.

Environmental contextAssessing environmental and human health impacts of chemical spills relies on information about how chemicals move across multiple environments. We measured volatile contaminants in the air above soil saturated with water to provide estimates of air concentrations of selected chemicals released to soil from an oil refinery in Texas during Hurricane Harvey. Estimated concentrations were below recommended exposure limits, even in a worst-case scenario. AbstractThe emission of volatile organic compounds (VOCs) from soil into air is affected by soil moisture dynamics, soil temperature, solar irradiance and carbon availability. The high amount of water in soil can modify its properties, which changes how VOCs interact. We conducted a comprehensive measurement of the soil–air partition coefficient (KSA) of VOCs into water-saturated soil with both low and high water contents for polar, weakly polar and nonpolar VOCs into a mineral soil (S-clay) and soil containing a high amount of organic matter (S-om) under a water-saturated condition. Partitioning of non-polar substituted aromatics (1,2-dichlorobenzene and toluene) was sensitive to the organic matter content in water-saturated soil. 1,2-Dichlorobenzene and toluene had higher affinities to S-om than to S-clay at all investigated water contents because of their strong interaction with the organic matter in soil. KSA decreased with elevated water content only for non-polar substituted aromatic VOCs. Less hydrophobic VOCs (benzene and trichloroethylene) exhibited similar partitioning into both soils by sorbing onto the air-water interface and dissolving in soil water, while the organic matter did not affect partitioning. The weakly polar and polar VOCs (methyl tert-butyl ether and 1-butanol) showed similar partitioning into both soils by dissolving in soil water while sorption to the organic matter was significant only at high soil water contents. KSA of VOCs on soil with high organic matter content correlated strongly with psat and Koa, but not on mineral soil. Estimates of the air concentrations for a subset of VOCs released from one refinery during Hurricane Harvey in 2017 in Harris County, Texas were lower than the recommended exposure limits, even under a worst-case scenario.