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The paper reviews the role of transcription factors that are part of the Yamanaka cocktail (OCT4, SOX2, KLF4, and c-Myc) in the mechanisms of tumor stem cell (TSC) differentiation (a pool of pluripotent cells), their participation in the malignant transformation of somatic cells, and in tumor progression. Their increased proliferative activity, which determines their malignant potential, was believed to be the main feature of tumor cells. Currently, there is more evidence supporting another concept that explains the continued tumor growth, metastasis, and resistance to therapy of most malignant tumors with a small, rest-ing, and rarely dividing population of pluripotent tumor cells. Year 2006 is considered to be the beginning of a new direction in developmental biology when Japanese researchers K. Takahashi and S. Yamanaka published the results of their studies on the properties of embryonic stem cells and experiments on direct reprogramming of somatic terminally differentiated cells.The research proved that four transcription factors were sufficient to maintain the pluripotent properties of cells, namely Oct4, SOX2, KLF4, and c-Myc, which were later called the Yamanaka cocktail. Such factors as SOX2and Oct4 are at the top of the hierarchy of transcription factors that regulate the pluripotent proper-ties of cells, their differentiation, and dedifferentiation. TSCs represent, albeit a complex, but very promising target for the development of innovative products for the diagnosis of and targeted therapy for neoplasms. From this point of view, the factors of pluripotency, which are parts of the Yamanaka cocktail, could be such promising targets, whose effect will probably be able to suppress or reduce the malignant potential of the most aggressive tumors and even prevent carcinogenic transformation in cases of precancerous pathology. Keywords: Yamanaka cocktail, OCT4, SOX2, KLF4, c-Myc, malignant transformation

Plant growth response to γ-irradiation includes stimulating or inhibitory effects depending on plant species, dose applied, stage of ontogeny and other factors. Previous studies showed that responses to irradiation could depend on ABA accumulation and signaling. To elucidate the role of ABA in growth and photosynthetic responses to irradiation, lines Col-8, abi3-8 and aba3 -1 of Arabidopsis thaliana were used. Seeds were γ-irradiated using60Co in the dose range 50-150 Gy. It was revealed that the dose of 150 Gy affected germination parameters of aba3 -1 and Col-8 lines, while abi3-8 line was the most resistant to the studied doses and even showed faster germination at early hours after γ-irradiation at 50 Gy. These results suggest that susceptibility to ABA is probably more important for growth response to γ-irradiation than ABA synthesis. The photosynthetic functioning of 16-day-old plants mainly was not disturbed by γ-irradiation of seeds, and no indication of photosystem II photoinhibition was noticed, revealing the robustness of the photosynthetic system of A. thaliana. Glutathione peroxidase activity and ABA concentrations in plant tissues were not affected in the studied dose range. These results contribute to the understanding of germination and photosynthesis fine-tuning and of mechanisms of plant tolerance to ionizing radiation.

The anthropogenic impact on urban rivers is very significant. Industrial enterprises, municipal, and agricultural organizations discharge wastewater directly into the rivers. In the samples of the studied water, certain properties were found. The water in the river is cloudy, brown in color, and in some places has a sharp smell. Extraneous impurities and foam were detected in water. Moreover, various chemicals were found, which are not characteristic to natural waters. The analyzed water is highly polluted as shown by the following chemical indicators, which reported results higher than the Maximum Allowable Concentration: Fe concentration is 24 times higher than standard, Cu is 5 times higher, Mn is 6 times higher, Al is 366 times higher, Hg is 3 times higher, Zn is 4 times higher, NO2 is 2.5 times higher, hydrocarbon pollution is 2.8 times higher, NH4 is 1.9 times higher. Therefore, it is necessary to immediately develop effective methods for monitoring the state of the watercourse, both economic and energetic. To save the sustainable development of the natural system.

Concentrations of main inorganic ions were determined in waters of city streams affected by domestic and industrial wastewaters – the Okhta and the Murinsky creek in St. Petersburg. It was shown that pollution of streams led to increasing of molar fraction for sodium ion and chlorides, decreasing of molar fraction of magnesium, calcium, sulfates and hydrocarbonates. These changes took place while electric conductivity of waters was increasing. Positive correlation coefficients (from 0.35 to 0.63) were found between molar fraction of sodium and parameters connected with wastewater pollutants: total nitrogen (TN), ratio of TN to TOC (total organic carbon), ratio of protein-like fluorescence (excitation at 230 or 270 nm, emission at 350 nm) to humic-like fluorescence (excitation at 230 or 270 nm, emission at 420 nm). The obtained results show that electric conductivity can be applied as an express-method for environmental monitoring in the studied streams. Additional use of ions molar fractions for such purpose is also possible.

The aim of this study was to investigate the effect of the external electrostatic field (ESF) on some hematological parameters in rats. Both in vivo and in vitro experiments were carried out. In in vivo investigations, rats were exposed to ESF (200 kV/m) during short (1 h) and long periods (6 days, 6 h daily). For in vitro study, the blood of intact rats was exposed to ESF for 1 h. Blood hematology was measured using validated ABX Micros ESV 60 Veterinary Hematology Analyzer. DNA damage in blood leucocytes was detected by means of comet assay. ESF effect on blood cell count was mainly manifested in white blood cells (WBC) and platelets. Damage of WBC was shown both in vitro and in vivo despite alterations in the count. This means the observed increase in WBC count in some cases might be a result of WBC compensatory mobilization from the bone marrow. Red blood cell (RBC) count and related parameters were slightly affected by ESF. Nevertheless, alterations in the shape and size of RBC were manifested. All ESF effects were extinguished in 14 days after the end of exposure. Bioelectromagnetics. 37:513-526, 2016. © 2016 Wiley Periodicals, Inc.

The article analyses the possibilities of a distance learning system for organizing the educational process in a medical university. It also considers the possibilities of independent work of students in the distance learning system. The article describes the options for using situational tasks as a form of independent work of medical university students. A situational task as a form of organizing independent work implements several educational goals. The situational task results in strengthening and systematizing knowledge, developing skills for self-organization, self-development, self-assessment, self-analysis in the learning process; and it can also result in developing critical thinking skills. The article deals with the functions of a teacher organizing the learning process, various forms of independent work, managing and supervising the work of students, and giving consultations on problematic issues, if necessary.

Waters of river Okhta and its tributary polluted with domestic wastewater were studied during several weeks of water storage at 20°C and 8°C. At sampling day, concentrations of total organic carbon in waters were close (17-24 mgTOC/L), polluted waters had difference in electric conductivity, increased concentration of total nitrogen (TN) and NH4 +. During storage, concentrations of TOC, inorganic carbon, TN, NH4 + declined, and the decline was stronger in polluted waters and at room temperature of storage. Spectra of optical density (D) of waters showed no significant qualitative difference between polluted and not polluted waters. During storage, D254 of all samples decreased up to 40% in 12 days. Polluted water had higher fluorescence intensity (I) at emission wavelengths 320-370 nm (up to 200%) and 420 nm (up to 50%). During storage of polluted water I decreased at 320, 350, 370 nm and increased at 420 nm. For pollution detection in not diluted waters at the sampling day and after 2 weeks of water storage the following parameters can be recommended: I230,350, I230,370 or I270,350 together with ratio of protein-like to humic-like fluorescence I230, 350/420 or I270, 350/420. These parameters can be used with or without correction of I for D.

The article deals with the categories of competency as the ability to apply knowledge, skills and personal qualities for successful and future professional activities and students’ professional-subjective attitude as an integrative personality trait, manifested in the willingness to master professional experience and based on the independent development of professional and personal qualities through initiative inclusion in creative professionally oriented activities. The formation of a professional-subjective attitude provides the basis for the development of professional competencies, which, in turn, are the key goal and the result of the educational process. The paper proposes a model for the formation of the professional-subjective attitude of the medical university students. The motivational, cognitive, professional-practical and professional-medical components are distinguished. The motivational component includes the motivation of a student to learn, to get a profession, to form a professional-subjective attitude and also involves self-estimation of the attitude by the student himself. The cognitive component considers the process of forming a professional-subjective attitude in the student’s educational activity (moreover, this process is conscious). The professional-practical component involves the formation of a professional-subjective attitude of students through activities in the educational environment attitude and problems solving.

River water samples were subjected to chemical and optical analysis. Pollution by city wastewaters was observed by increase of total nitrogen concentration (TN) and electric conductivity (EC) in water samples. In most cases pollution was followed by decrease of optical density at 254 nm $(\text{D}_{254})$ (by 10-50%) due to high natural background values. Pollution changed fluorescence intensity (I) for protein-like fluorophores (increase by 10-120%) and humic-like fluorophores (±15%). Calculations showed that measurement of $\text{D}_{254}$ with one detector was not informative for water quality monitoring because $\text{D}_{254}$ for polluted waters were in the frames of seasonal variation for the unpolluted waters in suburban part of river. Increase of I was able to detect presence of 10-90% of wastewater with the background of unpolluted river water. The best parameter for this was I at excitation wavelength 230 nm and emission wavelength 350 nm. Relative parameter F showing ratio of protein-like I to humic-like I was not informative in pollution monitoring.

Bilingual training of international students is a vocational training of learners with the use of two languages – English/French and Russian where the latter is a foreign language. The cultural approach regards culture as a key component integrated in science classes and humanities as well as language ones, aimed at cultural awareness that the students will heighten through constant reflection about the Self and the Others in order to develop linguistic and intercultural competences and facilitate a better understanding of a broader range of vocational contexts (scientific, social, clinical, political etc.) that the students are exposed to. Questionnaires, oral and written reports, classroom observations and interviews were used to collect the data. The findings show student’s positive perceptions of the cultural approach and highlight the value of explicitly considering a cultural component in content courses. Most students found the cultural approach as an effective way of facilitating intercultural communication and understanding.

Toxicity of industrial waters at several stages of treatment in model experiment was esteemed in Allium test. It was shown that ability of water to inhibit growth of onions roots decreased together with decreasing of organic matter content in dependence near to logarithmic. Qualitative difference between organic matter in treated and not treated water was observed. In not treated samples diluted to concentrations about 300–550 mgTOC/L toxic effect was 5 times higher than in not diluted waters at final stages of treatment with close content of organic matter (400-460 mgTOC/L). Toxic effect of treated water was close to that of tap water (used as control sample and for wastewater dilution).

Specific electric conductivity of water samples in a polluted urban stream was compared with other water quality parameters such as concentration of inorganic carbon, total organic carbon, and total nitrogen. Increasing of water conductivity 1.3...10 times was observed downstream canalization outlets discharging drainage waters together with residential waste waters from inhabited district of city. In some periods water conductivity showed good correlation with pollutants concentration such as TN and IC (with correlation coefficients 0.54...0.96). The received data show that electric conductivity can be used for revealing waste waters pollution in fresh surface waters.

Electric conductivity (EC), concentrations of major ions, total organic carbon, total nitrogen, optical density at 254 nm (D254) and fluorescence intensities characterizing protein-like and humic-like fluorescence were determined in water samples of urban river Okhta. Principal component analysis for values of measured parameters found 5-6 principal components (PC), three of them were explained by loadings values. PC1 was responsible for the most part of variance and reflected wastewater pollution with dissolved salts and organic matter. PC 2 was supposed to reflect organic matter of natural origin from the unpolluted stream water. Combination of EC and fluorimetric parameters of water were suggested for pollution monitoring in river waters.

The present study focuses on bilingual learners’ willingness to communicate (WTC) in English and foreign language anxiety (FLA) when speaking English in the classroom at Yugra State University. The paper reviews the theory, experiment and methods of pedagogical correction for those who are interested in these two phenomena in their research. The aim of the paper is twofold: to identify the main communicational difficulties faced by learners, explore the underlying causes, and provide some recommendations to overcome learners’ unwillingness to communicate in English actively and freely. The findings support the claims that FLA and WTC stem from issues with foreign language proficiency as well as some personal traits with FLA and WTC influencing each other and the process of mastering a second language.

Water from urban river Okhta polluted with domestic and industrial wastewaters was investigated. Specific electric conductivity (k), molar concentrations of ions Na+, K+, Mg++ and Ca++, concentration of total nitrogen (TN) were measured in water samples. Increasing of k happened together with increasing of molar fraction of sodium-ion (R Na ) among all studied cations (and correspondingly decreasing of molar fractions of other cations). Good correlations were found between R Na and TN (r = 0.67), k and TN (r = 0.84). The results support the idea of the leading role of wastewaters in changing of k and cations concentrations. Electric conductivity and RNa could be used to distinguish between polluted and not polluted waters in the Okhta.

The aim of this study was to investigate the effect of the external electrostatic field (ESF) on some hematological parameters in rats. Both in vivo and in vitro experiments were carried out. In in vivo investigations, rats were exposed to ESF (200 kV/m) during short (1 h) and long periods (6 days, 6 h daily). For in vitro study, the blood of intact rats was exposed to ESF for 1 h. Blood hematology was measured using validated ABX Micros ESV 60 Veterinary Hematology Analyzer. DNA damage in blood leucocytes was detected by means of comet assay. ESF effect on blood cell count was mainly manifested in white blood cells (WBC) and platelets. Damage of WBC was shown both in vitro and in vivo despite alterations in the count. This means the observed increase in WBC count in some cases might be a result of WBC compensatory mobilization from the bone marrow. Red blood cell (RBC) count and related parameters were slightly affected by ESF. Nevertheless, alterations in the shape and size of RBC were manifested. All ESF effects were extinguished in 14 days after the end of exposure. Bioelectromagnetics. 37:513-526, 2016. © 2016 Wiley Periodicals, Inc.

Water samples from urban polluted river (the Okhta) and its tributary (the Murinsky brook) in St. Petersburg were analyzed by spectrofluorimetry and photometry. Electric conductivity of water, concentrations of total organic carbon (TOC), total nitrogen (TN), and inorganic carbon (IC) were also measured. Correlations (r = 0.64–0.95) between TN and proteinlike fluorescence intensity of water (excitation 230 or 270 nm, emission 300–350nm) were found for both the river and the brook. These fluorimetric intensities and also ratio of fluorescence intensity at emission wavelengths 350 and 420 (at excitation 230) are recommended for water quality monitoring of the studied objects.

As documented in the Global Report on the Status of Women in the News Media (Global Report) (Byerly 2011), women are well represented in the media professions in all nations of Eastern Europe, but they ‘are in a particularly strong position in Russia’ (p. 12). Regarding women in governance in news media organizations, the Global Report found ‘variation in the Eastern European nations… ranging from 13.3 per cent in Hungarian companies to 41 per cent in Russian companies’ (p. 266). In what concerns women at the seniormanagement level, the Global Report also found that ‘women’s representation varies from 21.4 per cent in Estonian companies to 48.9 per cent in Russian companies’ (p. 266). Based on these data, Byerly (2011) asserted, ‘In both cases, Russian companies are considerably ahead of other nations in the presence of women in positions of policy and decision-making’ (p. 266). In the 14 Russian companies surveyed, women are above parity with men in top- and middle-level management, senior- and junior-level professional, as well as in technical professional, and sales, finance and administration, and they are almost at parity with men in production and design. Additionally, in these companies, women are employed predominantly in full-time positions with employment benefits and job security. Moreover, ‘salaries were found to be nearly equal for men and women in the Russian companies surveyed’ (p. 30), and job security was also found to be similar for men and women in these companies.