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Aflatoxin B1 is a hepatotoxic and hepatocarcinogenic compound. It is one of the common mycotoxins that causes various pathological conditions in humans and animals such as acute and chronic liver damage, neurological disorders, neoplasms and reproductive disorders.The present work was aimed to study the preventive effect of a dietary supplement based on milk thistle flour, succinic acid, bentonite, probiotic strain B. subtilis, vitamins A and E in experimental aflatoxicosis of laboratory animals. The experiments were carried out on 24 white rats, divided according to the principle of analogues into 4 groups. The first group - biological control, the second group - toxic control, the third and fourth groups were given medications against mycotoxin. White rats were injected with aflatoxin B1 with food at a dose of 500 µg/kg for 10 days. The treatments effectiveness was assessed by clinical signs of experimental animals and hemato-biochemical analysis. The level of exposure to aflatoxin B1 was evaluated by the state of the liver. The use of a biologically active additive significantly reduced the toxic effect of aflatoxin B1 on the animal organism, prevented a decrease in the amount of hemoglobin, leukocytes and erythrocytes, an increase in platelets, the activity of aminotransferases (aspartate aminotransferase and alanine aminotransferase), alkaline phosphatase and malonic daldehyde. There were no pathoana tomic changes in the internal organs of animals receiving a biologically active supplement.The results of the experiment indicate the high therapeutic efficacy of the biologically active additive used in aflatoxicosis, due to the multicomponent composition.

The development of the intellectual potential of an individual, as a complex characteristic of his intellectual, professional and creative capabilities, is emphasized in the youth policy state strategies of Russia and becomes the leading goal of the state program "Scientific and Technological Development of the Russian Federation". This makes it necessary to develop and implement innovative forms of training, productive educational models for training engineering personnel focused on solving innovative problems in the context of design and research activities, creating high-tech startups that form soft-skills and hard-skills competencies. In the context of our research, the directions of the development of the intellectual potential of engineering university students are determined: the application of the concept of the STEM approach in the context of the implementation of additional educational programs, which allows modeling students scientific, design and research activities based on the integration of consistency principles, variability, problem ranges, creativity, co-creation; implementation of team innovative technological projects involving the integration of research, scientific, practical-applied, creative, analytical and constructive skills of students; creation of a special information environment that allows to identify talented students focused on high-quality results, testing real scientific results at various venues, competitions, seminars, creating unique technological startups and thereby creating the basis for further successful professionalization of students.

The acid-base properties, structures, and tautomerism of protonated and free forms of carboxylic acid guanyl hydrazides (acylaminoguanidines) were studied using experimental and theoretical methods. According to the experimental data, guanyl hydrazides are relatively strong bases (pKa 8.1-8.9 in water at 25 °C) in spite of the presence of the electron-withdrawing carbonyl group in their molecules. The results of studying by NMR spectroscopy, X-ray diffraction analysis, and DFT calculations show that in polar media free guanyl hydrazides predominantly exist as zwitterionic tautomers (inner salts) with positive charge localization on the protonated guanidine moiety and negative charge localization on the deprotonated amide group.

In the article, the authors examine objects of scientific infrastructure, identify four types of large research infrastructures and analyze their functioning. Particular attention has paid to the study of practical experience and the specifics of organizing the work of research infrastructures in the EU, including the category of collective use of megascienceclass scientific complexes. The authors draw conclusions and recommendations on the use of the EU’s positive experience in this area for the organization of research infrastructure in Russia.

The reproductive method in the system of teaching Russian as a foreign language is aimed at reproducing the ways of activity by foreign students according to the algorithms presented by the teacher, at enriching them with knowledge, skills and abilities, as well as at forming the main mental operations: abstraction, analysis, synthesis, generalization, and others. When learning the «language of the profession», the main mental operations are formed: abstraction, analysis, synthesis, generalization, and others. The reproductive method, having the basis of algorithmization, integrated with the cognitive theory of learning, has reached a new level – the reproductivecognitive method. System analysis in combination with algorithmization becomes the basis of the reproductive and creative method. The methods outlined in the article enrich the knowledge, skills and abilities of students, which are most often carried out at the stages of correction, diagnosis and consolidation of knowledge, but do not guarantee the development of creative abilities, do not allow them to be systematically and purposefully formed. In particular, the concept of the reproductive-creative method is the principle of communicative orientation, which formed the basis of competence-based learning. In competence-based learning, the activity component, unlike other possible approaches, is considered from the viewpoint of competence, i.e., the ability of the student to effectively and independently, but with the help of the teacher, use the language being studied on the basis of the acquired experience in the form of knowledge, skills, and abilities. The knowledge obtained as a result of the use of the explanatory and illustrative method weakly forms skills and abilities. Therefore, thanks to the developed system of tasks, where the algorithmization of the educational process is clearly traced, the teacher organizes the students’ activities by repeatedly reproducing the knowledge communicated to them and the ways of activity shown.

Atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system (CNS) is an aggressive malignant tumor that is mainly found in younger children and is associated with poor prognosis. Our objectives: to present the results of treatment of children with CNS AT/RT under 3 years of age and assess the impact of various prognostic factors on patient survival. The study was approved by the Independent Ethics Committee and the Scientific Council of the N.I. Pirogov Russian National Research Medical University of Ministry of Healthcare of the Russian Federation. The study included 106 patients with CNS AT/RT aged 0–3 years who had been treated and monitored from 2008 to 2020. The median age was 16 (9; 23) months. All the patients underwent primary tumor resection with subsequent chemotherapy according to various protocols. At the time of the analysis, 47 patients (44.4%) were alive, 1 patient (0.9%) was lost to follow-up and 58 patients (54.7%) were dead, of whom 52 patients (90%) had died of disease progression and 6 (10%) – of polychemotherapy complications. One patient developed shunt-related intraabdominal metastasis within 10 months of the diagnosis. The 1-year progression-free survival (PFS) was 0.50; the 2-year PFS was 0.29; the 5-year PFS – 0.27. The median PFS was 12 months. The 1-year overall survival (OS) was 0.72; the 2-year OS was 0.53; the 5-year OS – 0.40. The median OS was 27 months. An analysis of patients with CNS AT/RT under 3 years of age showed that PFS was statistically significantly higher in: children aged > 12 months; children with totally resected tumours; children who had received polychemotherapy in accordance with the ATRT-2006 protocol that included radiotherapy and regional administration of a triplet of chemotherapeutic agents. The OS in patients with CNS AT/RT aged < 3 years was statistically significantly higher in: children aged > 12 months; children who had been treated with radiation therapy; patients who had received cytosar/etoposide intrathecally/intraventricularly; patients who had undergone high-dose chemotherapy with subsequent autologous hematopoietic stem cell transplantation. A multivariate analysis revealed that PFS was influenced by age, tumor location, extent of resection and exposure to radiation therapy, regional chemotherapy or high-dose chemotherapy with autologous hematopoietic stem cell transplantation, while OS was affected by age and exposure to radiation therapy.

The article presents an overview of current issues of international regulation of the content of heavy metals (lead, cadmium, mercury and arsenic) in food. Special attention is paid to the revision of the standards for the content of arsenic in rice, mercury in some types of fish, cadmium in chocolate, lead in meat, offal, and wine. A comparative analysis of the standards -permissible levels of content of heavy metals in food products in the EU and the Russian Federation is carried out.

The results of our own and foreign studies have shown the absence of sensitizing properties of terephthalic acid, and therefore there was a need to review the current hygienic standard – MAC – in the air of the working area and change the hazard class of the substance. The materials of the German Research Community (DFG) were used for substantiation of MAC. Recommended MAC in the air of working area is set at 5 mg/m3 (maximum single), a mixture of vapors and aerosol, hazard class 3.

The microstructure and distribution of residual stresses in the AMg6 alloy after laser shock treatment in the power density range of 1.3–6 GW/cm2 have been studied. Using X-ray structural analysis, it has been found that, after laser exposure, the size of the coherent scattering regions (CSR) decreases to 60 nm, the value of microstrains increases to 0.0018, and the average dislocation density increases from 6.6 × 1013 to 3.7 × 1014 m–2. Laser shock treatment forms residual compressive stresses to a depth of 1 mm, reaching –128 MPa on the surface of the material.

A microstructure and distribution of residual stresses after the laser shock peening of the AMg6 Al alloy without a protective coating were studied. The X-ray diffraction analysis showed the correlation between the parameters of the crystal structure and the profile of residual stresses of the treated samples. It was found that domain size decreased up to 50 nm, microstrains increased up to 0,0019 and average dislocation density increased up to 4,7·1014 м–2. Laser shock processing generates residual compressive stresses in depth up to 2 mm with a maximum of –120 MPa on the surface of the material. The profile and depth of the residual compressive stresses depend on the power density, overlap coefficient and the number of processing.

Changes in the parameters of miniature endplate potential (MEPP) of mouse diaphragm caused by exogenous application of two classical endocannabinoids, 2-arachidonoylglycerol (2-AG) (1 μM) and anandamide (AEA) (30 μM), were compared. A slowly developing stable increase in the MEPP amplitude by 50%, without affecting the frequency of MEPPs, was caused by 2-AG. This effect was prevented by AM-251, an inverse agonist of CB1-receptors, as well as by vesamicol, a blocker of the vesicular acetylcholine (ACh) transporter. On the contrary, AEA did not cause significant changes in the MEPP amplitude but induced a slowly developing (within 2 h) increase in MEPP frequency by 75% on average. The effect of AEA was prevented by AM-251 (1 μM) as well as by blocking of L-type Ca2+-channels with nitrendipine (1 μM) and inhibition of PKA activity by H89 (1 μM). It was concluded that both 2-AG and AEA are able to exert a noncanonical facilitating presynaptic effect on spontaneous ACh release. Even though these endocannabinoids activate the same type of CB-receptors, their facilitating effects do not overlap and are strictly aimed either at potentiating the size of ACh quanta (in case of 2-AG) or increasing the frequency of MEPP (in case of AEA). We assume that different intracellular targets and signaling pathways may be involved in the differentiated facilitating effects of 2-AG and AEA in mouse neuromuscular junctions.

This work presents the results of experimental study of post-irradiation variation (fading) of SO PD (DTS) dosimeter readings within the interval from 1 to 100 days after radiation loading by reactor (BR-K1) and bremsstrahlung (LU-10-20) gamma quanta within the interval of absorbed doses from 50 Gy (water) to 10 kGy (water). There is advanced a formalism for fading correction of dosimeter dose readings based on the application of exponential and logarithmic forms of the functional dependence for the ratios of the light-transmission coefficient conditioned by radiation loading and its values obtained at arbitrary time points after irradiation is completed.

Currently, perfluorooctanoic acid (PFOA) has no hygienic standards in the air of the working area and objects of the human environment in the Russian Federation. By the decision of the Stockholm Convention SC-9/12, PFOA, its salts and derivatives are included in Part I of Annex A of the Stockholm Convention on Persistent Organic Pollutants in 2019 (with exceptions for possible use). The Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade included PFOA, its salts and derivatives in the list of potential candidates for inclusion in Annex III of the Rotterdam Convention at the next meeting COP10 in 2021. The use of this chemical on the territory of the Russian Federation entails water and air pollution. Industrial emissions and waste water from fluoropolymer production, thermal use of materials and products containing polytetrafluoroethylene, biological and atmospheric degradation of fluorotelomer alcohols, waste water from treatment facilities are the sources of the release of PFOA into the environment. Analysis of international databases has showed that PFOA is standardized in the air of the working area in Germany, Japan, and Switzerland. In the countries of the European Union, as well as the USA and Canada, the issue of PFOA standardizing in drinking water is being now actively under discuss. Taking into account the high toxicity and hazard of the substance and the serious concern of the civil society of the Russian Federation, the Federal Service for Supervision of Consumer Rights Protection and Human Wellbeing requested the Russian Register of Potentially Hazardous Chemical and Biological Substances to develop MACs for perfluorooctanoic acid in the air of the working area and water as soon as possible. The MACs for PFOA have been proposed using risk analysis: 0,005 mg/m3, aerosol, hazard class 1 – in the air of the working area and 0,0002 mg/L, the limiting hazard indicator – sanitary-toxicological, hazard class 1 – in the water.

The nonlinearity of the gate–drain current–voltage characteristics in classical Schottky transistors and two-dimensional electron gas field-effect transistors based on AlGaAs/InGaAs/GaAs and InGaAs/GaAs compounds is analyzed. The carrier velocity-overshoot effect in the transistor channel is analyzed for various doping profiles of the structures under study.

The article provides an overview of the main directions of development of EU legislation in the field of pesticides regulation. Special attention is paid to the problems of neonicotinoids, glyphosate, endocrine disruptors, and food quality control for the content of residual amounts of pesticides.

The purpose of the article is to identify the “author’s prints” of Ilya Ilf and Evgeny Petrov in the novels “Dvenadtsat’ stul’ev” (“The twelve chairs”) and “Zolotoy telenok” (“Golden calf”) through highlighting the both writers’ contribution to the fusion of inspiration and jokes. A detailed comparison of Petrov’s “pre-Ilf” and Ilf’s “pre-Petrov” works with their co-written texts demonstrates that the co-authors definitely used accumulated literary material in creating the novels: the “common cauldron” contained their previous plots and images. The article is based on a textual analysis of Ilf’s and Petrov’s stories and feuilletons published in the Moscow press before they started writing together, as well as the texts written in the process of creating the dilogy. In previous research on the Ilf and Petrov’s work, the links between their early texts and the co-written dilogy were either unsystematically presented, or tried to track the path of the “literary evolution” of Ilf and Pertov, who had been gradually honing their idiostyle and writing technique. It was often done without following rigid structure and not representing proper arguments. The article offers a classification of identified borrowings and references from Ilf and Petrov’s early texts. It contains systematized examples of various types and scales – from a single detail to a large fragment of the narrative. The catalog of “auto-references” confirms the regular character of borrowings: during the creation of “Dvenadtsat’ stul’ev” (“The twelve chairs”) and “Zolotoy telenok” (“Golden calf”), coauthors often used “previously formulated” phrase and motifs from works, which had been written separately. However, passages from feuilletons, as a rule, were transferred by writers to new novels not mechanically: in the novels “old” images were selected and developed by both authors.

Metal complexes (metal: ligand = 1 : 1) have been obtained via the reaction of 4-R-5-nitrophthalonitriles with erbium and lutetium acetates and chlorides. 1 : 2 heteroleptic complexes have been synthesized based on them, containing unsubstituted and octasubstituted phthalocyanine ligands at the metal atom. The products have been characterized by a set of physico-chemical methods.

The mechanisms underlying changes in spontaneous release of acetylcholine (ACh) induced by exogenous agonists and antagonists of endocannabinoid receptors were investigated by recording miniature endplate potentials (MEPPs) in motor synapses of mouse diaphragm preparations with intracellular microelectrodes. There have not been observed any statistically significant changes either in the membrane potential of muscle fibers or in the frequency, amplitude, and time parameters of the MEPPs under the action of AM-251 (1 μM), antagonist/inverse agonist of CB1 receptors, for 60 min. Activation of CB receptors by their exogenous agonist WIN 55,212-2 (WIN) (20 μM) for 1 h did not cause statistically significant changes in the amplitude of the MEPPs. However, MEPP frequency increased by more than 50% as compared to the control under the action of WIN for 30–60 min. Blocking of CB1 receptors by AM-251 (1 μM) prevented the WIN-induced increase in MEPP frequency. A protein kinase A inhibitor H-89 (1 μM) did not prevent the enhancement of the ACh secretion upon activation of CB receptors by WIN. WIN lost the ability to increase MEPP frequency in the presence of a phospholipase C inhibitor U73122 (5 μM), which did not affect by itself the amplitude and temporal characteristics or MEPP frequency. A protein kinase C inhibitor, chelerythrin (4 μM) or ryanodine, which blocks the ryanodine receptors (RyRs) at a concentration of 5 μM, also prevented the WIN-induced increase in MEPP frequency. Thus, a signaling cascade triggered by stimulation of presynaptic CB1 receptors with subsequent activation of phospholipase C, protein kinase C, and the release of stored calcium, leading to an increase in the frequency of spontaneous quantal release of ACh, has been detected for the first time in mouse motor synapses. This suggests the presence of CB1 receptors on the presynaptic membrane in mouse motor nerve terminals and the possibility of activation of these receptors by endocannabinoids for potentiating the spontaneous secretion of ACh.

The microstructure and distribution of residual stresses in AMr6 alloy after the laser shock processing in the range of power density 1—6 GW / cm2 have been studied. By the X-ray diffraction method it was found that domain size decreased up to 60 nm, microstrains increased up to 0,0018 and average dislocation density increased by a factor of 5,5 in comparing with untreated material (3,7×1014 м–2 vs. 6,6×1013 м–2). The laser shock processing generates residual compressive stresses in depth up to 1 mm, with a maximum of –128 MPa on the surface of the material.

Neurofibromatosis type I (NFI) is one of the most common brain tumor predisposition syndromes. Children with NFI are prone to develop a low grade gliomas, which can be localized in various areas of the brain, however, most of them occur in the structures of the optic pathway: optic nerves, chiasm, tracts and optic radiations – that is, are optic pathway gliomas (OPG). This retrospective study included children with newly diagnosied low grade glioma of the optic pathway at the age from 0 to 18 years with NFI, who underwent medical examination and / or treatment at the Burdenko Neurosurgery Institute from January 1, 2003 till December 31,2015. Atotal from 264 patients 42 (16%) had clinical manifestations of NFI. The ratio of boys and girls was 1:1. The median age was 4.25 years (range 4.5 months – 17 years). Visual disturbances were the most frequent clinical manifestation of the tumor. Surgical resection was performed in 18 patients. The remaining 24 patients OPG were diagnosed based on clinical and radiological findings: 9 patients were in observation group, 11 patients chemotherapy was carried out, three were given radiation therapy, and spontaneous regression of the tumor was recorded in 1 patient. Progression of the disease was observed in 14 patients in our cohort. The overall survival rate in patients with NFI was 98 ± 2% at 5 years. Event free survival rate was 68 ± 7% at 5 years.The study was approved by the Independent Ethics Committee of N.N. Burdenko National Medical Research Center of neurosurgery Ministry of healthcare ofRussian Federation.