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In this article, series of questions related to the conceptual basis for studying the characteristics of the emergence and evolution of the "fake news" phenomenon are proposed. An analysis is made of the transformation of information strategies and political communications in a digital society and the relationship of fake news with interpretations of social traumatic events are fixed. [ABSTRACT FROM AUTHOR]

Statistical analysis is an integral part of every experiment, since it helps researchers to make conclusions out of the work done. Textbooks with detailed description of the algorithms for statistical analysis exist, as well as diverse software packages. Statistical methods are, however, often applied incorrectly, which leads to erroneous and inadequate conclusions. The present article is an attempt to determine the main problems emerging in the course of statistical analysis of experimental results in the field of environmental microbiology. For instance, the classical parametric tests, which are most often used in experimental articles (t-test, analysis of variance, Pearson correlation coefficient, etc.), are applicable only when a random variable of n independent observations has normal distribution. Importantly, the normality of the distribution must be proved, and it is possible to do only for minimal sample size of 20‒30 independent observations per group. The latter is crucial for the incubation, isotope, and molecular biological experiments. The family of normal distributions is not the only family of parameter-dependent (parametric) distributions of random variables. Moreover, real-life distributions usually differ from the normal ones, and normal distribution may be considered only as a certain approximation. High diversity of parametric families complicates the choice of criteria and statistical tests for analysis of a set of data collected from n independent observations. Nonparametric statistics may be of help, since it is free of sample size and distribution requirements, although, as any method of analysis, it also has limitations. An increasing number of experimental data, including those in the field of environmental microbiology, are nowadays analyzed by using nonparametric statistics, which indicates a certain tendency for substitution of parametric methods by nonparametric ones. [ABSTRACT FROM AUTHOR]

Abstract: A seasonal study of microbial methane oxidation (MO) and sulfate reduction (SR) processes in bottom sediments was carried out at five stations in the estuarian Sevastopol coastal area, which differed in their sedimentation and geochemical conditions. High methane concentrations in bottom sediments, as well as accordingly high MO rates, were obtained at stations marked by high organic carbon (Corg) concentrations. The dependence of these values was found to be exponential, whereas for SR, the amount of organic carbon was not the limiting factor. For the studied stations, the integral SR rates ranged from 2.9 to 11.3 mmol m-2 day-1. The trends of the SR rate have opposite directions for the open and closed parts of the sea: SR decreased during study period at the center of the bay, while in the open sea area it increased. The MO rates varied in a wide range from 0.0001 to 3.6 mmol m-2 day-1; the highest were obtained in Corg-rich sediments of the central part of the bay. Only at one station, where the mean annual Corg content in sediments reached 3.39%, did the methane concentration in sediment pore water exceed the calculated solubility. [ABSTRACT FROM AUTHOR]

While most pathogenic bacteria are efficiently removed from wastewater during biological treatment, some pathogens, notably Arcobacter, may be abundant in the purified water. Using 16S rRNA gene profiling, the composition of microbial communities of municipal wastewater in the city of Moscow was studied before and after biological purification at the Lyubertsy wastewater treatment plant. Fecal contaminants of the genera Acinetobacter, Aeromonas, Arcobacter, Bacteroides, Streptococcus, and Veillonella, which include human pathogens, predominated in the influent wastewater. After treatment, the relative abundance of these bacteria decreased by 50‒100 times. Predominant organisms in the microbiome of the effluent water were bacteria characteristic of activated sludge, including the nitrifiers of the genera Nitrospira and Nitrosomonas, as well as phosphate- and glycogen-accumulating microorganisms. Thus, pathogenic bacteria, including Arcobacter, are effectively removed at the Moscow wastewater treatment plant. [ABSTRACT FROM AUTHOR]

The results of helminthological and bacteriological studies of rodents (squirrels) and insectivores (hedgehogs) of the urban biotope are presented. Causes of helminthiases outbreaks were studied. The possibility of the use of information about helminth fauna and the invasion intensity of micromammals by helminths as indicators of anthropogenic pollution are pointed. The possible measures for fighting and prevention of the helminthiases of micromammals inhabiting in the urban forest area of Moscow are proposed. [ABSTRACT FROM AUTHOR]

Biochemical and hematological parameters of clinically healthy birds of prey of three species of the order Falconiformes contained in the conditions of kennel were investigated. The data obtained were analyzed in relation to their importance for assessing health status of the birds. Macro and microscopic study of faeces as well as detection of helminth eggs were carried out. Extensiveness of helminth invasion of 13 bird species in kennel was 24.6%. 7 helminth species were identified. The highest frequency of occurrence was found for nematode Capillaria falconis, which may indicate the formation of the resistant foci of capillariasis in the conditions of aviary. [ABSTRACT FROM AUTHOR]

The physicomechanical properties of polymer composites based on aramide fibers that are obtained by the wet-spinning technique with the use of epoxy binders are discussed. The chemical structures of reinforcing fibers and components of epoxy binders; the microstructures, surface structures, and some properties of aramide fibers; and the processes of manufacturing high-strength reinforced composites on their basis are described. Some product samples made of these composites are presented. The investigated reinforcing materials possess high tensile strengths and tensile moduli, which make it possible to obtain products with a high level of operational characteristics on their basis. [ABSTRACT FROM AUTHOR]

The review deals with the unique microbial group responsible for anaerobic ammonium oxidation with nitrite (anammox), and with the role of this process in development of the biotechnology for removal of nitrogen compounds from wastewater. The history of the study of this process is briefly related. Up-to date knowledge on the intracellular organization, energy metabolism, growth stoichiometry, and physiology of anammox bacteria is described, and the main methods for cultivation of these microorganisms are characterized. Special attention is paid to the problems associated with practical application of anammox bacteria, which result from their extremely slow growth, the absence of pure cultures, and the interaction with other microbial groups. [ABSTRACT FROM AUTHOR]