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The article shows the results of experiments on biological reclamation of a pilot production site. Wastes from hydrometallurgical processing of clinkers from the Belovsky zinc plant (Kemerovo region) were chosen as objects. Various approaches were considered, in which the technogenic soil and its mixture with a humus substrate were sown with yellow sweet clover and awnless brome. As a result of the analysis of samples, the degree of soil acidity, cation exchange capacity, fractional composition, concentrations of mobile phosphorus and potassium, organic carbon, and the content of mobile forms of elements in an acetate-ammonium buffer solution were determined. The results obtained were evaluated according to agrochemical gradations and hygienic standards. The conducted studies allow us to conclude that technogenic soil is a substrate with unfavorable physical and agrochemical properties. Mixing man-made soil with a fertile soil layer does not improve its properties.

The article presents the results of studies of the microelement composition of feathers of wild birds kept in the conditions of zoos in Moscow and Ivanovo. The aim of the study was to study the content of some heavy metals and arsenic in representatives of the cockatoo subfamily – Cacatuinae (White cockatoo – Cacatua alba, Sulper-crested ccockatoo – Cacatua galerita), and birds of subfamily Psittacinae – Blue-fronted Amazon – Amazona aestiva, Burrowing parakeet – Cyanoliseus patagonus assessing the health status of birds. In 2018–2020, parrot`s feathers were studied for the accumulation of zinc, copper, iron, lead, cadmium and arsenic by the atomic absorption method. The data on the features of the content of chemical elements in different species of parrots are given. In the course of the study, it was found that according to the value of the average content in the feathers of parrots, the studied elements form the following decreasing series: Fe> Zn> Cu> Pb> Cd> As. In parrots kept in zoos, there is a tendency to a decrease in the proportion of zinc and copper in 38,4%, an increase in iron and cadmium in 30,8% and 38,4% of individuals, respectively. Deviations in the fluctuations of lead and arsenic in the studied sample of birds were equally in the direction of increasing and decreasing their content in biosubstrates in 38,4% of individuals; 30,8% of the studied birds in terms of the content of iron, zinc and cadmium in feathers, 46,1% in terms of copper, 23,1% in lead, 7,7% in terms of lead are in a state of “pre-illness” and require additional examinations. In the fan of the parrots, a significant increase in the concentration of lead in the grooves, in comparison with the rod, by 3,98 times and a decrease by 2,83 times in the level of zinc accumulation was established. Revealed a significant average direct relationship between the level of Zn and Pb, Zn and Cd, Cu and Pb, Cu and Cd; Fe and As; Cd and As and inverse average relationship between the level of Pb and Cd; Pb and As in bird feathers. To improve the trace element status of parrot’s zoological institutions, it is necessary to conduct monitoring studies with a frequency of 1 time per six months with an assessment of the level of chemical elements on centile scales.

The aim of the study was to study the content of some heavy metals and arsenic in frozen fish (capelin, herring, pink salmon, chum salmon, pollock, blue whiting, greenling) used for feeding animals of zoological institutions. In the course of the study, it was found that according to the value of the average content in fish used by zoological institutions for feeding wild and exotic animals, the studied elements form the following decreasing series: Fe > Zn > Cu > As > Pb > Cd. In the course of nonparametric statistics, significant differences were established in the level of accumulation of all studied elements, except for Pb and Cd, by representatives of different fish families. Herring is characterized by a high level of accumulation of Zn and As, low – Cd, salmon: high concentration of Fe, Pb, Cd, low – Cu and As. Greenlings to a greater extent than other families contain Cu, to a lesser extent – Zn and Fe. The rest of the elements in the representatives were kept at an average level. In the studied fish samples, the excess of MPC was not found. The presence of a reliably weak direct correlation the relationship between the content of Pb, Cd and As in fish and animal biosubstrates was established, and the antagonism between the intake and accumulation of the following elements in the body of birds and mammals was statistically confirmed: Zn – Pb, Cu – Pb and Zn – Cd. The accumulation of As in biosubstrates is facilitated by the intake of Zn and Cd, and Cu – Zn.

The aim of the study was to study the content of some heavy metals and arsenic in members of the Cricetidae family of hamsters and to develop centile scales for assessing the level of accumulation of these elements for the Central Federal District. In 2018–2020, hamster`s wool was studied for the accumulation of zinc, copper, iron, lead, cadmium and arsenic by the atomic absorption method. The data on the characteristics of the content of chemical elements in different sexes of animals are given. In the course of the study, it was found that, according to the value of the average content in the wool of animals of the family, the studied elements form the following decreasing series: Fe> Zn> Pb> Cu> Cd> As. When studying the features of the accumulation of chemical elements by different sexes, a significant increase in the concentration of zinc, iron, cadmium and arsenic in the wool of males was established, compared with females, depending on the species, from 1,38 to 3,98; from 1,28 to 1,52; from 2,00 to 304,00 times, respectively. With regard to the accumulation of copper in the body, the opposite trend is observed. In females, its concentration is 1,5–3,19 times higher. In the studied sample of animals, an increase in copper content was revealed in 44,83% of individuals and a decrease in cadmium in 44,82%.

The chromatographic behavior and adsorption of enantiomers of glycylaspartic acid on the Nautilus-E chiral stationary phase with grafted eremomycin antibiotic were studied. Acetate buf er mixtures with variable pH prepared in a water—methanol mixed solvent (volume ratio 60 : 40) were used as acetate buf ers. The retention of Gly—Asp was found to be enantioselective and depending on the ratio of various ionic forms of dipeptide in the mobile phase. The ratio is determined by the pH. A model of adsorption equilibrium assuming independent binding of diverse ionic forms with the stationary phase, which is characteristic of energy uniformity, was proposed. This model is well consistent with the experimental data. Features of application of the equilibrium dispersion and transport dispersion dynamic elution models for the determination of the adsorption isotherms by the inverse method are discussed.

The medium-scale (50–200 km in the projection onto ionospheric altitudes) splitting of the field-aligned currents flowing out of the ionosphere has been considered in the case when the approximation of the distribution function of hot magnetospheric ions by the kappa distribution is taken into account. It was assumed that the condition of magnetostatic equilibrium and isotropy of hot magnetospheric plasma pressure is satisfied in the magnetosphere. The theoretical parameter of magnetospheric plasma hot stratification has been obtained for the case of ion kappa distribution. The parameter characterizes the number of structures into which the band of the field-aligned current flowing out of the ionosphere is split. The theoretical predictions have been compared with the observations on the Intercosmos-Bulgaria-1300 and Aureol-3 satellites. It has been indicated that the number of measured structures is in better agreement with that of the theoretically predicted structures in 70% of cases if the non-Maxwellian tails of ion distribution functions are taken into account.

The particle flux fluctuations along the trajectory of polar orbitting satellite Intercosmos-Bulgaria-1300 are analyzed. The comparison of forms of fixed energy auroral particles fluctuation spectra with theoretically predicted in the suggestion of particles thermalization give the possibility to show that not only plasma sheet ions but also plasma sheet electrons are unmagnetized.

Different E. coli of 0-groups, enteropathogenic (EPEC), enteroinvasive, enterotoxigenic (ETEC) and diarrheogenic in sporadic child diarrhea (DESCD), regarded as the causative agents of enteric infections, were detected in 70-80% of cases (1,146 E.coli carriers) in the feces of child and adult patients with acute enteric infections (AEI) irrespective of their age; in 35% of cases the same patient had a combination of two or more varieties of EPEC, ETEC or DESCD. Only EPE were excreted by 3.5-11.3% of patients, depending on their age; only ETEC were excreted by 1.7-3.4% of patients and only DESCD, by 23.1-32.8%. In 30-40% of cases diarrheogenic E.coli of the corresponding 0-groups were isolated as monocultures. The complex of bacteriological criteria, serving as the basis for the diagnostics of AEI (the necessity of the quantitative and qualitative characterization of the contamination of the seed material, E.coli serological labeling, the determination of E.coli pathogenicity factors) is discussed.

The content of enterobacteria in fecal samples obtained from 1,146 patients with acute enteric infections was studied. In the first days of the disease about 70% of the patients were found to have abundant and highly diversified intestinal microflora with Escherichia contamination of feces constituting 10(6)-10(7) microbial cells/g in children and 10(7)-10(8) microbial cells/g in adults. The number of patients excreting Escherichia and pathogenic enterobacteria increased from 8.8% (children under 6 months) to 28.6% (adults), the number of patients excreting Escherichia and opportunistic enterobacteria decreased from 69.1% (children under 6 months) to 36.8%. In 75% of cases the reverse relationship between the number of Escherichia and opportunistic enterobacteria was registered, the latter numbering two and more genera in 50% of cases. The serological picture of Escherichia was poorer when they were isolated simultaneously with shigellae (83 O-groups) than in those cases when Escherichia alone were isolated (108 O-groups), or when Escherichia were isolated simultaneously with opportunistic enterobacteria (119 O-groups).

To obtain the information on the genetic control of toxin production in the botulism causative agents, the oligonucleotides were synthesized as the molecular probes by translation of the amino acid sequence of the botulinic type A neurotoxin. The optimal conditions for hybridization of botulinic DNA with the synthetic DNA probes were determined and the probes specificity was demonstrated. The DNA fragments homologous to the probes used were shown to belong to bacterial genome, but not to bacteriophage one.

Most of the kaolin deposits are confined to weathered paleolithic rock. Intensively metamorphosed rocks lie above the weathered depth while below they gradually change into permanent parent rocks. The deposits of kaolin which arise from leucocratic, porphyric, and other granites are of the greatest industrial interest. When they are formed, the ironmineral ores (pyrites, magnetite, etc.), of course, dissolve and are removed. In the first stage of weathering these ferrous silicates produce ferrous montmorillonite minerals which change into kaolinite. During this process some of the iron and titanium is removed while some remains inside the flakes of kaolinite and lowers the whiteness [i].

C. freundii enteropathogenic strains were found to be capable of producing choleroform thermolabile enterotoxin. Thus, in the study of 96 C. freundii strains 38 enterotoxin-producing cultures (39.5%) were revealed by means of the molecular-biological techniques and 29 such cultures (30.0%), by means of the radioimmunoassay (RIA). 100% coincidence was noted in the results of tests for enterotoxigenicity, made by means of RIA or hybridization techniques with the use of the LT-probe containing a cloned fragment with the gene coding the synthesis of LT-enterotoxin in enterotoxigenic Escherichia coli. At the same time only 29 out of 38 Citrobacter strains found to be positive in the hybridization tests, yielded the positive result when tested in RIA for the presence of LT-enterotoxin. This fact should be taken into consideration in the determination of enterotoxin-producing cultures isolated in acute enteric infections, as the method of genetic probing is capable of bringing out the genetic information in bacteria even in the absence of its phenotypical expression.

The conditions of cultivation, ensuring the maximum accumulation of intracellular thermolabile enterotoxin in the cultures of two E. coli strains of different origin, have been studied. Culture media manufactured in the USSR have been selected and the conditions of cultivation, necessary for obtaining intracellular thermolabile enterotoxin in preparative amounts, have been established. Under these conditions the yield of thermolabile enterotoxin in 1.4 mg per 1 liter of culture medium for strain H74-114 and 1.0 mg per 1 liter of culture medium for strain 86.

The modified method for isolation and purification of LT-enterotoxin from Escherichia coli strain H74-114 has been proposed. Modification is based on exclusion of concentration of bacterial cell lysates by 3-5 fold dilution and changing PH during chromatography. The proposed modification permitted to increase the yield of purified and active product 8-10 fold. The obtained preparations are homogenic due to PAAG-SDS data and immunochemical analysis. B-component of TL-enterotoxin is shown to consist of 4 subunits B in contrast to B-component of choleragen, consisting of 5 subunits. The mol mass of A component of both toxins is identical but in contrast to choleragen the component of LT-enterotoxin is not subject to proteolysis.

Out of 4,082 Escherichia strains isolated from 989 hospitalized patients with acute enteric infections 2,979 strains belonged to 139 O-groups and the remaining strains could not by typed with O-sera (O1-O164) or were in the serological R-form. 19.3% of the strains isolated from 354 patients showed a positive reaction for thermolabile enterotoxin (TLET) determined in the radioimmunoassay. Escherichia with pronounced reaction for TLET were isolated from 5.5% of the patients. The serological picture of Escherichia with a positive reaction for TLET comprised 78 O-groups, showed practically no variations in children of different age and adult patients and was related to the intensity of reaction for TLET. The number of enterotoxigenic Escherichia greatly varied within individual O-groups: from 3.1 +/- 3.63% (O11) to 100 +/- 9.81% (O114) of the total number of known strains in these O-groups. In most O-groups the number of enterotoxigenic strains varied from 10% to 50%. The most widely spread serovars of etiologically important enterotoxigenic Escherichia belonged to 24 O-groups and were often isolated as monocultures. The capacity for producing TLET (and, probably, some other antigenically related substances) in widely spread among Escherichia; still, the determination of enterotoxicity is a necessary, but not sufficient criterion of their etiological importance in acute enteric infections.

A solid phase variant of radioimmunoassay has been elaborated for screening toxin-producing strains of E. coli and V. cholerae grown on agar plates. The method is based on the ability of cholera-like toxins to be absorbed on nitrocellulose filters and their further identification with the use of homologous sera and [125I]-A protein from staphylococci. Sensitivity of the method reaches 20 pg. The proposed technique permits identification of intracellular enterotoxin and is aimed at a massive screening of E. coli strains, NAG-vibrios and V. cholerae strains for toxin production.

Posibilidades de predecir las variaciones de Dst basándose en sus valores previos fueron estudiados usando un perceptron de multicapas con alimentación directa. Fue encontrado que el índice Dst puede ser autopredicho con unas horas de anticipación. Ambas fases (principal y de recuperación) son predichas correctamente con hasta 3 horas de anticipación. Pero para predicciones más avanzadas se observa un desplazamiento entre la posición del mínimo de Dst observado y el predicho. El uso de diferentes índices de chorro auroral como parámetro de entrada mostró que existe una baja correlación entre ellos y el Dst. Tormentas débiles y moderadas son bien predichas, en cambio los valores de predicción para Dst para tormentas más intensas son menos negativas que los mínimos observados; este resultado podría estar relacionado con la conocida saturación de índices de chorro auroral durante el desarrollo de tormentas intensas. Predicciones con base en el índice PC muestran mejor correlación con Dst. A pesar de que la amplitud de variación de Dst no se reproduce correctamente, no existe el desplazamiento temporal entre el mínimo de Dst medido y predicho.