The influence of anthropogenic pollution, particularly with polycyclic aromatic hydrocarbons (PAHs) on soil toxicity and spread of antibiotic resistance genes (ARGs) is extremely important nowadays. ...We studied 20 soil samples from a technogenically polluted site, municipal solid wastes (MSW) landfills, and rural settlements in the southwestern part of the Rostov Region of Russia. A close correlation was established between the results of biosensor testing for integral toxicity, the content of genes for the biodegradation of hydrocarbons, and the concentration of PAHs in soils. The relation between the quantitative content of ARGs and the qualitative and quantitative composition of PAHs has not been registered. Soils subjected to different types of the anthropogenic pressure differed in PAHs composition. The technogenic soils are the most polluted ones. These soils are enriched with 5 ring PAHs and carry the maximum variety of assayed ARGs, despite the fact that they do not receive household or medical waste.
•At biotesting soils contaminated with industrial PAHs are more toxic than landfills.•Technogenically polluted soils are enriched with 5 ringPAHs compared to landfills.•Technogenically polluted soils contain more diverse ARGs.
•The high content of pollutants negatively affects bacterial biodiversity.•The structure of soil microbiome depends on the pollutant type.•Pollutants have diverse effects on different bacterial taxa.
...Metagenomic studies of soil microbocenoses are extremely relevant nowadays. The study of pollution impact on soil microbiomes is of particular interest. The structure of microbial communities in soils with different levels of pollution by polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) was studied. High bacterial biodiversity was found in all the studied soil samples, but its lowest values are found in soil samples taken on the territory of technogenically polluted Lake Atamanskoye. Assessment of soil pollution showed the highest content of polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) for the soils Lake Atamanskoye. The high content of pollutants negatively affects the abundance of representatives of the phyla Actinobacteria, Planctomycetes, Verrucomicrobia, and Nitrospirae. Such phyla as Proteobacteria, Candidate Divisions TM7, OD1, WPS-2, Chlamydiae, Cyanobacteria are characterized by positive direct correlation with the content of pollutants, especially with PAHs. A cooperative effect of decrease in the number of Actinobacteria and Proteobacteria with an increase in Armatimonadetes probably corresponds to PTEs contamination. The proportion of Candidate Division OD1, Chlamydiae, Cyanobacteria, and Candidate Division WPS-2 was increased in the soil microbiome under the influence of severe combined pollution. Pollutants negatively affect the abundance of dominant unclassified_o__Gaiellales and unclassified_o__WD2101 genera. Iamia, Salinibacterium, Arthrobacter, Kaistobacter, Thiobacillus genera are characterized by a low abundance, but they are presumably the most resistant to soil pollution. It was revealed that the level of soil pollution largely determines the composition and diversity of bacterial communities in the soils of the studied territories. Operating taxonomic units have been established that have prognostic value for assessing the state, level of soil pollution, and their biological safety.
Dormancy is the final stage of tuber life serving to preserve tubers as organs of vegetative reproduction under unfavorable growth conditions. Since the duration of potato tuber dormancy and their ...sprouting time have significant economic importance, much attention is given to the study of the regulation of these processes. This review considers metabolite, genetic, and hormonal aspects of regulation of potato (Solanum tuberosum L.) tuber dormancy and sprouting. Particular attention is paid to the relationship between processes occurring in different parts of the tuber: its storage tissues and buds. The interaction of hormonal and metabolite (carbohydrate) regulation of dormancy and sprouting is discussed.
The behavior of the mixtures 6Al
2
Si
2
O
7
: 12NaOH and 6Al
2
Si
2
O
7
: 12NaOH : 2Al
2
O
3
during heat-treatment was studied by means of x-ray diffraction and simultaneous thermal analysis. It was ...shown that hydrated zeolite LTA forms after ultrasonic treatment and evaporation of a suspension, granulation of paste, and drying. It was determined that sodium aluminum silicate Na6Al
4
Si
4
O
17
is synthesized at temperatures up to 700°C. Sodium aluminum silicate Na
8
Al
4
Si
4
O
18
, mullite, and nepheline were found in the systems after heat-treatment at temperatures above 800°C. It is shown that the calculations performed by Friedman’s isoconversion method (differential) and the Kissinger–Akahir–Sunose (integral) method, for which the temperature interval 500 – 800°C is of interest, give close values of
E
. The growth of the apparent energy of activation with increasing degree of transformation attests a change in the reaction mechanism.
Tuber formation is a complex process comprising several stages: stolon formation and growth, induction of tuberization, tuber initiation, and tuber growth. This review considers successive stages of ...tuber formation and their hormonal regulation. Special attention is paid to the effects on tuber formation of such phytohormones as gibberellins, cytokinins, jasmonic acid, and auxins. Physiological and some molecular-genetic aspects of their action on tuber photoperiodic induction and initiation are discussed.
Six new fluorescent derivatives of 1,8-naphthalimide were synthesized. Three were dyes, and three were fluorescent whitening agents (FWAs) containing a tetramethylpiperidine (TMP) stabilizer ...fragment. The FWAs were obtained under phase-transfer catalysis conditions. Five of the compounds were copolymerized with methyl methacrylate, so copolymers with an intense color and/or fluorescence stable against solvents were obtained. The chemical bonding of the synthesized monomers in the polymers was confirmed spectrophotometrically. The participation of the monomer compounds did not significantly affect the process of copolymerization or the molecular masses of the obtained copolymers. The quantity of chemically bonded naphthalimide monomer in the copolymers was determined to be over 60%. The spectral properties of the compounds and their photostability in solution and in the copolymers were studied. The influence of the compounds on the photostability of the copolymers was determined. The compounds, especially those containing a stabilizer (TMP) fragment in their molecules, showed a positive stabilizing effect on the photodegradation of poly(methyl methacrylate). Polyamide fabrics with 2-allyl-6-hydrazino-benzodeisoquinoline-1,3-dione, 2-allyl-6-(2-amino-ethylamino)-benzodeisoquinoline-1,3-dione, and 2-chloro-N'-(2-methyl)-1,3-dioxo-2,3-dihydro-1H-benzode isoquinoline-6-yl) acetohydrazide were dyed, and materials with an intense yellow color and fluorescence were obtained. Cotton fabrics were whitened with 2-(2,2,6,6-tetramethyl-piperidin-4-yl)-6-methoxy-benzodeisoquinoline-1,3-dione, 2-(2,2,6,6-tetramethyl-piperidin-4-yl)-6-allyloxybenzodeisoquinoline-1, 3-dione, and 2-2-(2,2,6,6-tetramethyl-piperidin-4-yl)-1,3-dioxo-2,3-dihidro-1H benzo deisoquinoline-6-oxyethyl-2-methacrylate, and materials with bright whiteness and intense bluish fluorescence were obtained.
The synthesis of five new reactive triazine azodyes and their intermediates was investigated. Three of these dyes contained a tetramethylpiperidine (TMP) fragment and four of them contained a ...polymerizable group in their molecule. Two different reaction schemes for synthesis were studied and the most suitable one was found. The quantitative thin-layer chromatography (Tlc) to monitor the synthesis was applied. Cotton fabrics were dyed and their color characteristics were measured. The dyes copolymerized with acrylamide (ACA) and acrylonitrile (AN) and the copolymers with an intense orange color that is stable to solvent extraction were obtained. The photostability of the dyes in solution and on cotton fabrics was studied and it was found that two of the dyes, containing a TMP fragment, had good photostability and can be recommended.
Nanocrystalline TiO
2
samples, obtained by sol–gel and supercritical fluid (SCF) methods, have been studied by optical spectroscopy and electron spin resonance. It is established that the main type ...of spin centers in SCF samples are Ti
3+
/oxygen vacancy centers and conduction electrons. Radicals (
,
) and (
) are found in the samples doped with nitrogen and carbon, respectively. The energy levels of defects in the band gap of the structures studied are determined. It is explained why samples with close values of nanocrystal sizes, specific surface area, and defect concentration have a significantly different photocatalytic activity in the visible spectral range. It is found that impurity centers with energy levels near the middle of the semiconductor band gap must be incorporated into TiO
2
to obtain samples with the highest photocatalysis rate. New possibilities for developing energy-efficient (without UV irradiation) photocatalysts are discovered.
Samples of nitrogen-doped titanium dioxide (anatase, 0.2 ≤ N ≤ 1.0 wt%) prepared by the sol–gel method were investigated using X-band electron paramagnetic resonance spectroscopy, photoconductivity, ...and photocatalysis measurements. N· and NO· paramagnetic defects in N-TiO
2
have been observed; their concentrations and spin-Hamiltonian parameters were calculated. An increase both in the rate of the generation of free charge carriers and in the rate of photocatalysis was found in N-TiO
2
in contrast with non-doped titania under visible light. The correlation of the density of the observed radicals with the photoconductivity and photocatalysis data is discussed.
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