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Objectives. The aim of this study was to identify variation patterns of the in-series variation coefficient of adhesive strength to base and the dependency of the frost resistance coefficient on the criterion of adhesion on prescription factors of fine-grained concrete obtained from dry building mixtures based on various Portland cements containing various low-modulus inclusions and redispersible polymer powders from 0 to 3%. According to GOST 31357, the main quality indicators of the hardened mixture or fine-grained concrete, in addition to frost resistance, include the indicator of “frost resistance of the contact zone”, which characterises the ability of the hardened concrete to maintain adhesion to the base during normal separation following a certain number of freeze-thaw cycles.Method. The tests of the main samples were carried out after 75 freeze-thaw cycles in accordance with GOST 31356. The marks of the frost resistance of the contact zone are set from FKZ25 to FKZ100. The number of freeze-thaw cycles is taken as a mark, after which the adhesion strength to the base, determined according to GOST 31356, is at least 80% of the strength of the control samples. The arithmetical average is taken at between at least 5 values, while the variation coefficient measured across a series of adhesion strength values is not considered.Results. The average values of the variation coefficient of adhesion strength were: following 75 cycles of freezing-thawing – 0.224 (in a range from 0.058 to 0.616); following 25 cycles of freezing-thawing – an average of 0.129 (in a range from 0.016 to 0.352). The variation coefficient of adhesion strength can exceed the variation coefficient of compression strength by approximately 2.5 to 3 times. When introducing the redispersible powders into the structure of fine-grained concrete, there is no unambiguous pattern of change in the values of the variation coefficient of adhesion to base and it is possible to increase or decrease this value, while the values of the variation coefficient of adhesion can vary by an order of magnitude.Conclusion. For all concretes, there is a tendency of increase of the coefficient of frost resistance with a decrease in the adhesion variation coefficient both after hardening under normal conditions as well as during cyclic freezing and thawing. When conditions VF/V28A

Objectives This study was aimed at identifying the dependency of the frost resistance of the contact zone of fine-grained concretes (FGCs) obtained from dry building mixtures (DBMs) based on various Portland cements (PCs) with the content of various redispersable polymer powders (RPPs) from 0 to 3%.Method The research was based on 75 freeze-defrost cycles.Results Although the average dependency of adhesion with the base on additional porosity after 75 freeze-defrost cycles does not depend on the nature of NMV, adhesion is influenced by the cement type, the type and dosage of RPPs, as well as the nature of additional porosity. Since the content of organised volume of NMV in the form of VV has no effect on changes in adhesion with the concrete base following 75 freeze-defrost cycles, it is impractical to add more than 7% of NMV in the form of MS to the concrete mixture. The feasibility of using sulphate-resistant cement requires more research. The practical RPP dosage should be 1-2%. Some contradictions in conclusions on the volume of the introduced MS (by the strength criterion – at least 6%, by the criterion of frost resistance of the contact zone – no more than 7%) allows us to recommend the dosage of MS in RPP within 6-7% by volume for obtaining additional data on the MS effect on frost resistance.Conclusion The dependency of compressive strength on additional porosity for FGCs without NMV and with NMV in the VV form after hardening during 28 days under normal conditions almost coincides with the known dependency of strength on porosity for cement stone; the maximum divergence of the values ???????? ????0 in the investigated range does not exceed 5%. The dependency of compressive strength on additional porosity for FGCs without NMV and with NMV in the MS form is similar to the known dependency of strength from porosity for cement stone; however, with increasing porosity, there is a slight decrease in the effect of porosity on strength. The dependency of compressive strength after 75 freeze-defrost cycles on additional porosity for FGC without NMV practically coincides with the previously obtained dependency of strength on porosity for cement stone; the maximum divergence of the values ???????? ????0 in the investigated range does not exceed 9%. For FGCs with NMV in the MC form, increasing porosity causes a slight decrease in the porosity effect on strength, and for FGCs with NMV in the VV form, the dependency has a quantitative and qualitative difference. The value of NMV in the VV form recommended for improving the frost resistance of FGCs by the strength criterion is at least 3%, MS – at least 6%. According to the criterion of the frost resistance of the contact zone and the strength of MS, the recommended dosage is 6-7%. It was not possible to disclose the direct impact of the VV volume on the frost resistance of the contact zone.

Objectives Reliability and durability of structures using materials with various properties (plaster coatings, cement glue, new concrete during repair and restoration of structures, etc.) largely depends on the adhesion of the layers and the deformation properties of the coatings. To obtain the required properties of materials used for coatings, modifiers based on polymers and low-modulus inclusions are introduced into the composition of new concretes, for example, entrained air. The aim of the work is to identify some patterns of change in the properties of concrete with the joint introduction of these modifiers.Method Experimental determination of the tensile strength in bending, compression, E-modulus, adhesion to the concrete base by standard methods.Result The influence of separate and joint introduction of dispersible polymer powders and various low-modulus inclusions into the composition of fine-grained concrete has been established.Conclusion The joint introduction to the composition of fine-grained concrete of various low-modulus inclusions and redispersible polymer powders provides a reduction in the stress level during forced deformations due to the different effects additives on the strength and deformation properties and contributes to increased adhesion to the concrete.

Vitamin D3 transporter (DBP) is a multifunctional protein. Site-specific deglycosylation results in its conversion to group-specific component protein-derived macrophage activating factor (GcMAF), which is capable of activating macrophages. It has been shown that depending on precursor conversion conditions, the resulting GcMAF activates mouse peritoneal macrophages towards synthesis of either pro- (IL-1β, TNF-α—M1 phenotype) or anti-inflammatory (TGF-β, IL-10—M2 phenotype) cytokines. The condition for the transition of the direction of the inflammatory response of macrophages when exposed to GcMAF is the initial glycosylated state of the population of DBP molecules and the associated effective deglycosylation of DBP by β-galactosidase. In vivo experiments with GcMAF exhibiting anti-inflammatory properties on models of induced arthritis in mice and cystitis in rats indicate a significant anti-inflammatory effect of the macrophage activator. The feasibility of unidirectional induction of anti-inflammatory properties of macrophages allows creation of combined therapeutic platforms where M2 macrophages are among the key therapeutic components.

Introduction. People in helping professions are more prone to emotional burnout and depression. Even at the university level, future physicians experience an increase in depressed mood. Despite the fact that this problem has been studied quite extensively, the role of socio-cognitive factors has not yet been studied enough. The purpose of this research is to fill this gap and explore the relationship between career anchors and the level of depressed mood among Russian medical students. Materials and Methods. The survey was conducted in 2020 and 2021. The sample of the survey included 864 students of the SSMU named after V. I. Razumovsky. Methods used in the survey: the Zung Self-Rating Depression Scale (SDS), adapted by T. I. Balashova and the diagnosis of career anchors, using Schein’s Career Orientations Inventory (COI) in the adaptation of V. A. Chiker. Data analysis methods: Shapiro‒Wilk and Fligner‒Killeen tests, Wilcoxon‒Mann‒Whitney and Nemenyi tests, and biweightmidcorrelation analysis. The search for predictors of depressed mood was carried out using the method of generalized additive models. Results. Career anchors are predictors of depressed mood. Service orientation and professional competence reduce the severity of depressed mood, while the relationship is non-linear. The desire of students to integrate different areas of their lives and organize the activities of other people is negatively associated with depressed mood, but the relationship is linear. The severity of depressed mood is exacerbated by career anchoring on autonomy. Discussion and Conclusion. The results of the study contribute to the understanding of the complex relationship between depressiveness and socio-cognitive factors. The results of this study can be instrumental in the development of a set of measures reducing the risk of depression in medical professionals by studying at a university.

Macrophages are the immune cells of high-immunological plasticity, which can exert both pro- and anti-inflammatory activity, as well as repolarize their phenotype to the opposite or neutral one. In this regard, M2 macrophages of the tumor-associated stroma (TAS) are a promising therapeutic target in treating malignant neoplasms. Using FACS assay, we have estimated the CD11b+/Ly-6G+/Ly-6C+ fraction of macrophages from the peritoneum and TAS in intact healthy mice and those with developed Lewis carcinoma, both untreated and treated according to Karanahan technology in combination with group-specific macrophage activator (GcMAF-RF). As well, the pattern of pro- and anti-inflammatory cytokines mRNA expression in different groups of experimental and tumor-bearing animals was assessed. It was found that: (i) exposure of intact mice to GcMAF-RF results in the increased number of CD11b+/Ly-6C+ peritoneal macrophages and, at the same time, the expression pattern of cytokines in peritoneal macrophages switches from that characteristic of the mixed M1/M2 phenotype to that characteristic of the neutral M0 one; (ii) combination of Karanahan technology and GcMAF-RF treatment results in M0/M1 repolarization of TAS macrophages; (iii) in tumor-bearing mice, the response of peritoneal macrophages to such a treatment is associated with the induction of anti-inflammatory reaction, which is opposite to that in TAS macrophages.

Objective: Glioma is a highly invasive tumor, frequently disposed in essential areas of the brain, which makes its surgical excision extremely difficult; meanwhile adjuvant therapy remains quite ineffective. Methods: In the current report, a new therapeutic approach in curing malignant neoplasms has been performed on the U87 human glioblastoma model. This approach, termed “Karanahan”, is aimed at the eradication of cancer stem cells (CSCs), which were recently shown to be capable of internalizing fragments of extracellular double-stranded DNA. After being internalized, these fragments interfere in the process of repairing interstrand cross-links caused by exposure to appropriate cytostatics, and such an interference results either in elimination of CSCs or in the loss of their tumorigenic potency. Implementation of the approach requires a scheduled administration of cytostatic and complex composite double-stranded DNA preparation. Results: U87 cells treated in vitro in accordance with the Karanahan approach completely lost their tumorigenicity and produced no grafts upon intracerebral transplantation into immunodeficient mice. In SCID mice with developed subcutaneous grafts, the treatment resulted in reliable slowing down of tumor growth rate (P < 0.05). In the experiment with intracerebral transplantation of U87 cells followed by surgical excision of the developed graft and subsequent therapeutic treatment, the Karanahan approach was shown to reliably slow down the tumor growth rate and increase the median survival of the mice twofold relative to the control. Conclusions: The effectiveness of the Karanahan approach has been demonstrated both in vitro and in vivo in treating developed subcutaneous grafts as well as orthotopic grafts after surgical excision of the tumor.

Substances for manufacture of parenteral drugs require control by the «Bacterial Endotoxin» (BE) Index with the LAL-test. The aim of the study was to show possible applicability of organic solvents in BE determination by the gel-thromb test in case of water-insoluble pharmaceutical substances. The results confirmed that ethyl alcohol practically had no effect on the endotoxin activity. In the routine assays it is advisable to test solutions of the substances at the alcohol concentration of 6% below.

The use of the LAL test as a method for determining bacterial endotoxins (BE) allows us to normalize the content of impurities causing a pyrogenic reaction in patients. Increasing the reliability and reproducibility of this method is promoted by validation procedures, which are an integral part of the methods for determining BE and are based on the construction of a «model experiment» where the test and control samples are compared. Depending on the test procedure (gel-clot or photometric tests) for determining the presence of BE, appropriate validation procedures are used to assess the necessary parameters. The purpose of the study: to prove the possibility of interchangeability of the methods for determining BE with the help of validation procedures on the example of the drug «Ceftriaxone powder for intramuscular injection 500 mg». Research techniques: Gel-clot and Kinetic Chromogenic tests. The results of the conducted tests confirm the reproducibility and specificity of the LAL test methods. The sensitivity of the LAL reagent used is confirmed. In the experiments of the gel-clot test for Ceftriaxone, a dilution of 1:160 of the base solution in the concentration of 100 mg/ml was validated. The parameters of the calibration curve in the Kinetic Chromogenic test corresponded to the validation requirements (CV0.98). Determination of the bacterial endotoxin content in Ceftriaxone by the photometric method is possible at the same 1:160 dilution, where the accuracy of determination of the BE in the test sample is

Introduction: Karanahan , a cancer treatment technology aimed at eradicating tumor-initiating stem cells, has already proven effective in 7 tumor models. Karanahan comprises the following procedures: (1) collecting surgical specimens, (2) determining the duration of the DNA repair process in tumor cells exposed to a cross-linking cytostatic agent, and (3) determining the time point, when cells, including tumor-initiating stem cells, are synchronized in the certain phase of the cell cycle after triple exposure to the cytostatic, becoming vulnerable for the terminal treatment, which is supposed to completely eliminate the rest of survived tumor-initiating stem cells. Determining these basic tumor properties allows to design the schedule for the administration of a cross-linking cytostatic and a complex composite DNA preparation. Being conducted in accordance with the schedule designed, Karanahan results in the large-scale apoptosis of tumor cells with elimination of tumor-initiating stem cells. Methods: Breast tumor specimens were obtained from patients, and basic tumor properties essential for conducting Karanahan therapy were determined. Results: We report the first use of Karanahan in patients diagnosed with breast cancer. Technical details of handling surgical specimens for determining the essential Karanahan parameters (tumor volume, cell number, cell proliferation status, etc) have been worked out. The terminally ill patient, who was undergoing palliative treatment and whose tumor specimen matched the required criteria, received a complete course of Karanahan . Conclusions: The results of the treatment conducted indicate that Karanahan technology has a therapeutic potency and can be used as a breast cancer treatment option.

The control of transverse magneto-optical Kerr effect (TMOKE) enhancement is realized by balancing the radiative and absorption losses in one-dimensional all-nickel magnetoplasmonic crystals. The modulation of the surface shape tunes the plasmonic radiative losses and coupling of the incident light with surface plasmons. The maximal magneto-optical response corresponds to the optimal coupling implemented with the equality of radiative and absorption losses. A slight deviation from the optimal corrugation depth results in a significant reduction of the TMOKE value.

The article describes a method of comparative economic evaluation of technologies or options for the development of mineral deposits by underground mining, which, according to the mining and geological conditions, under these conditions may be alternative. It is shown that in modern conditions of changing technological structures, the hardening of the real economy involves the development of methods for evaluating the effectiveness of industrial technologies on a competitive basis. Definitions of terms and concepts in mining practice are given. As a criterion for evaluating the economic efficiency of the compared development systems, traditionally accepted is the magnitude of the conditional profit from mining and processing of ores in all areas of mining. The concepts of conditionally variable reduced costs are clarified. An algorithm for calculating the conditional profit for the technologies used for the extraction and processing of ores and the determination of them economically optimal is given. The technology indicators necessary for minimization of economic consequences from ore losses at the considered technology are determined. The approach to the definition of equivalent economic relations between indicators of the developed area is formulated. The conclusion is made about the feasibility of using the proposed methodology for the assessment of technology in order to optimize technological solutions at the design stage of a field for development with economic effect.

Abstract Background We have characterized the human cell line arised from the Epstein–Barr virus (EBV) positive multiple myeloma aspirate subjected to the long-term cultivation. This cell line has acquired the ability to form free-floating spheres and to produce a xenograft upon transplantation into NOD/SCID mice. Methods Cells from both in vitro culture and developed xenografts were investigated with a number of analytical approaches, including pathomorphological analysis, FISH analysis, and analysis of the surface antigens and of the VDJ locus rearrangement. Results The obtained results, as well as the confirmed presence of EBV, testify that both biological systems are derived from B-cells, which, in turn, is a progeny of the EBV-transformed B-cellular clone that supplanted the primordial multiple myeloma cells. Next we assessed whether cells that (i) were constantly present in vitro in the investigated cell line, (ii) were among the sphere-forming cells, and (iii) were capable of internalizing a fluorescent TAMRA-labeled DNA probe (TAMRA+ cells) belonged to one of the three types of undifferentiated bone marrow cells of a multiple myeloma patient: CD34+ hematopoietic stem cells, CD90+ mesenchymal stem cells, and clonotypic multiple myeloma cell. Conclusion TAMRA+ cells were shown to constitute the fourth independent subpopulation of undifferentiated bone marrow cells of the multiple myeloma patient. We have demonstrated the formation of ectopic contacts between TAMRA+ cells and cells of other types in culture, in particular with CD90+ mesenchymal stem cells, followed by the transfer of some TAMRA+ cell material into the contacted cell.

Metasurfaces are not adjustable after fabrication, and a critical challenge is to realise a technique of tuning their optical properties that is both fast and efficient. Here, Shcherbakov et al. realise an ultrafast tunable metasurface with picosecond-scale large absolute reflectance modulation at low pump fluences.

The purpose of the disclosure of the nature and role of economic efficiency and competitiveness in the process of analyzing activity in the manufacturing industry in this article identified the approaches to the specification of a data entity economic categories. In this regard, work on the basis of the review retrospective analysis of theoretical research existing definitions in this direction; it is revealed that in the modern economic literature single point of view chosen by the majority of scholars, the definition of these concepts at the present stage yet. The authors found that competitiveness as an integrated indicator of economic efficiency implies more complex relationships between economic entities in comparison with the efficiency, which in this context acts as an indicator of a degree of efficiency of use of available enterprises limited resources.

Aim: to evaluate features of the functional state of microvascular bed of the skin in patients with pulmonary arterial hypertension associated to congenital cardiac disease (PAH-CCD) and chronic thromboembolic pulmonary hypertension (CTEPH). Methods. In study included 25 patients (41.6±15.8) with PAH-CCD, 25 patients (48.8±14.2) with CTEPH and 25 healthy volunteers (39.3±10.1 years). All the patients underwent a six-minute walking test (6-MWT), transthoracic echocardiography, thorax organs radiography, right heart catheterization (RHC) and Laser Doppler flowmetry (LDF) with amplitude and frequency wavelet analysis of blood flow oscillations and evaluation of constrictory and dilatatoryskin resistive microvesselsfunctions. Results. In the PAH-CCD in relation to the CTEPH groupaccording to the RHC were noted significantly higher values of systolic pressure in pulmonary artery (93.2 and 77.8 mm Hg respectively) and venous mixted blood saturation(63 and 57% Hg respectively). On this background 6- MWT distance was 356 and 325 m, the Borg dyspnea scale index was on average 3.12 and 3.76 respectively. According to the LDF pulseoximetry PAH-CCD and CTEPH patients had 90.1 and 94.7% respectively. According to the LDF with amplitude and frequency wavelet analysis the PAH-CCD patients had sig-nificantly higher values of the amplitude of myogenic, respiratory and pulse sectionof blood flow modulation, and also increased constrictory activity smooth muscle cells of skin precapillary arterioles in response to the stretching at venous occlusion and decreased dilatatory reserve at post-occlusi-ve reactive hyperemia. According to the LDF the CTEPH patients had elongationof time development of microvessel constriction in response to acti-vation of sympathetic nervous systemin respiratory and cold tests. Conclusion. According to the LDF functional state of skin microvessels in systemic circulation of the CTEPH patients was comparable with control groupexcept for elongation of time development of microvessel reactions for sympathetic vasoconstrictor stimulations. The PAH-CCD patients demonstrated basal tonus decreasing of smooth muscle cells of skin precapillary arterioles in systemic circulation, which can be regarded as a manifestation of autoregulatory response to systemic hypoxia.

Aim: To evaluate features of the functional state of microvascular bed of the skin in patients with idiopathic pulmonary arterial hypertension (IPAH) depending to acute vasoreactivity testing on inhaled nitric oxide. Methods: in study included 28 patients with IPAH (mean age 39,8±13,2 years) and 25 healthy volunteers (39,3±10,1 years). All the patients underwent 6-minuts walking test (6-MWT), transthoracic echocardiography, thorax organs radiography, right heart catheterization (RHC) with acute pharmacological test (APT), laser Doppler flowmetry (LDF) with functional tests. Patients were divided into 2 groups by results of APT. Results: according to the LDF the APT+ patients didn't differ from control group on any of the parameters. The APT-patients according to the basal perfusion also were comparable with control group, but had significantly higher constrictory reactions for all types vasoconstrictor stimulations (at activation of sympathetic nervous system in respiratory and cold tests, and in the development venule-arteriolar constrictory response on venous occlusion) and elongation of time development post-occlusive reactive hyperemia. We identified significant correlation of the amplitude of respiratory section of blood flow modulation, which reflected degree of venule plethora, with the RHC parameters and functional status of patients. Conclusion: In the APT-patients on against a background the of uncharged basal perfusion parameters noticed increased constrictory activity smooth muscle cells of resistive microvessels for all type vasoconstrictor stimulations, but expression of constrictory reactions correlated with indications of patients functional status.

A functional analysis of 167 genes overexpressed in Krebs-2 tumor initiating cells was performed. In the first part of the study, the genes were analyzed for their belonging to one or more of the three groups, which represent the three major phenotypic manifestation of malignancy of cancer cells, namely (1) proliferative self-sufficiency, (2) invasive growth and metastasis, and (3) multiple drug resistance. 96 genes out of 167 were identified as possible contributors to at least one of these fundamental properties. It was also found that substantial part of these genes are also known as genes responsible for formation and/or maintenance of the stemness of normal pluri-/multipotent stem cells. These results suggest that the malignancy is simply the ability to maintain the stem cell specific genes expression profile, and, as a consequence, the stemness itself regardless of the controlling effect of stem niches. In the second part of the study, three stress factors combined into the single concept of “generalized cellular stress,” which are assumed to activate the expression of these genes, were defined. In addition, possible mechanisms for such activation were identified. The data obtained suggest the existence of a mechanism for the de novo formation of a pluripotent/stem phenotype in the subpopulation of “committed” tumor cells.

The relevance of scientific research due to the fact that the study of the impact of the major issues of motivation on the formation and reproduction of the human capital in the social market economy, characterized by such elements on the basis of which the formation of human capital and its development.

The article deals with the concept of an innovative economy as the knowledge economy, reflecting the different theoretical approaches to the understanding of the nature and content of the category of “human capital." We consider the problems of reproduction of the human capital, the study of managing this process in terms of innovative development of territories. The article presents a systematization of approaches to the definition of “human capital".

Relevance of scientific research is caused by that efficiency of use and development of the human capital is the main priority for the majority of the leading countries of the world. Human capital promotes growth of quality of life of the population, and also increase in efficiency of national economy in general.

Relevance of the real research is caused by transition of Russia to information society. In such society new organizational forms - the virtual organizations representing networks of the economic agents cooperating in information space are of particular importance.