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The development of new approaches to suppressing cardiac arrhythmias requires a deep understanding of spiral wave dynamics. The study of spiral waves is possible in model systems, for example, in a monolayer of cardiomyocytes. A promising way to control cardiac excitability in vitro is the noninvasive photocontrol of cell excitability mediated by light-sensitive azobenzene derivatives, such as azobenzene trimethylammonium bromide (AzoTAB). The trans-isomer of AzoTAB suppresses spontaneous activity and excitation propagation speed, whereas the cis isomer has no detectable effect on the electrical properties of cardiomyocyte monolayers; cis isomerization occurs under the action of near ultraviolet (UV) light, and reverse isomerization occurs when exposed to blue light. Thus, AzoTAB makes it possible to create patterns of excitability in conductive tissue. Here, we investigate the effect of a simulated excitability gradient in cardiac cell culture on the behavior and termination of reentry waves. Experimental data indicate a displacement of the reentry wave, predominantly in the direction of lower excitability. However, both shifts in the direction of higher excitability and shift absence were also observed. To explain this effect, we reproduced these experiments in a computer model. Computer simulations showed that the explanation of the mechanism of observed drift to a lower excitability area requires not only a change in excitability coefficients (ion currents) but also a change in the diffusion coefficient; this may be the effect of the substance on intercellular connections. In addition, it was found that the drift direction depended on the observation time due to the meandering of the spiral wave. Thus, we experimentally proved the possibility of noninvasive photocontrol and termination of spiral waves with a mechanistic explanation in computer models. [ABSTRACT FROM AUTHOR]

One of the most critical tasks of modern energy is accumulating thermal energy due to the inefficient use of thermal energy during the underloading of power systems in which heat-accumulating materials are used. Therefore the paper studies the effect of alternating electric current on the heat-accumulating properties in a mixture based on Na2SO4·10H2O. It is established that the AC effect leads to an increase in the melt crystallization temperature of Na2SO4·10H2O and Na2S2O3·5H2O and also contributes to the return of heat. The selection of the treatment mode of the Na2SO4·10H2O–Na2S2O3·5H2O (50: 1 wt.) mixture by the AC was carried out. It was shown that the latent heat of melting of 329 kJ/kg is achieved at 500000 Hz frequency. [ABSTRACT FROM AUTHOR]

The importance of studying terminology in maritime higher educational institutions is beyond any doubt. Poor proficiency in professional English vocabulary may cause problems in communication between multinational crew and threaten the safety of life, ship and cargo at sea. Thus, mastering of the vocabulary is and will always be the main direction in teaching a foreign language for professional purposes. The paper analyzes the main types of lexical units that form the termbase of maritime English. Effective ways of mastering professional vocabulary are provided. At the same time, it is noted that teaching shall be provided and complied with the terms of a professionally oriented approach, where all decisions regarding the selection of the syllabus are coordinated with the professionally oriented communicative requirements of cadets. It means that the cadets study lexical units which are required for further application in specific areas and situations, taking into account the professional direction.The special lexical units that are considered as a substantial component of a special lexical competence which acts as an integrative phenomenon and has level structure and includes knowledge about special lexical units, skills of using studied special lexical units in a given communicative context are discussed. Some aspects of marine terminology which are necessary for cadets’ familiarization when studying the course “Foreign language (English)” have been considered.It is noted that a combination of various tactics and teaching methods with the use of illustrative materials to the use of original professional documents such as ship's instructions, checklists and others is useful and productive when studying professional English terminology. The combination of all these methods will allow the cadets to have an integral “linguistic” pattern of their future profession, from individual words and word combinations to the functioning of lexical units in a real professional language.

Dependences of free Gibbs energies GL and GS on the component content and temperature are analyzed for binary eutectic alloys, which are characterized by terminal solid solubility and are present in liquid (L), liquid–solid (LS), and solid (S) states. Using additional Gibbs energy GLS for the liquid–solid state, conditions for the most stable alloys in this region and melting (and solidification) paths during L → LS → S transitions are determined. [ABSTRACT FROM AUTHOR]

The processes of melting and solidification of the eutectic Sn-43 mol % Bi alloy are studied by cyclic thermal analysis. It is found that this alloy melts at a temperature T = 412 K (which corresponds to the reference melting temperature of the eutectic) upon heating and solidifies isothermally at a temperature T = 394 K upon cooling; that is, the temperature difference is Δ T = 18 K. A comparison of temperatures T and T reveals a temperature hysteresis (TH). The activities and the activity coefficients of tin and bismuth in the eutectic are calculated at temperatures T and T . The enthalpies of melting at T and solidification at TS are measured. The ways of changing the Gibbs energy during TH are determined. [ABSTRACT FROM AUTHOR]

The composition of equilibrium solid phases NaCl, NaSO, NaCO · 2NaSO (berkeyite) and NaCl, NaCO · HO, NaCO · 2NaSO (without preparative determination), saturating E and E eutonic solutions respectively, was established via nonvariant area boundary determination in a NaCl-NSO- NaCO-HO system at 50°C with the use of a combined method. [ABSTRACT FROM AUTHOR]

The article is devoted to the topical issue of social and cognitive grounds of commitment to a social community of a country and describes the results of the empirical research of the role of figurative sphere and social well-being of an individual in emergence of sovereign emigration intentions. The author has operationalized the notion of socioculturally integrated personality imaginative sphere and has designed the image and association test procedure to determine the intensity of the phenomenon, meant by the notion. 200 people (120 females and 80 males) aged 18 to 35 took part in the experiment. The research has revealed that commitment to one’s country is connected with high socioculturally integrated personality imaginative sphere. It has also proved that emigration intentions occur among both individuals with low and high satisfaction with social well-being. Low socioculturally integrated personality imaginative sphere appears to be one of the major predictors of sovereign emigration intentions. The article can be an interesting basis for further empirical and theoretical studies. This work was supported by the Russian Foundation for Humanities (project № 16-06-50134 «Commitment to one's country and emigration intentions: social and cognitive grounds»).

The article is devoted to the problem of organizing in-service supervision of a beginning teacher in educational environment. The conceptual and practical ways of designing the model of in-service supervision of a young teacher are analyzed in the article. In-service supervision is defined as a purposeful complex process involving the cooperation of teachers-mentors with a young specialist in order to ensure successful entry into the profession, effective teaching, adaptation to the professional environment and overcoming crises and barriers arising in the process of teaching. The model of in-service supervision is based on a convention generation approach. A set of complementary principles of organizing in-service supervision is described. The model of in-service supervision is founded on the institution of double mentoring: a mentor from teachers’ education university staff and a mentor from school supervise a beginning teacher. The in-service supervision is based on mentoring technology. The authors describe the developed website for online in-service supervision, allowing timely, prompt interaction with a young teacher. The article analyzes the system of criteria for choosing a mentor as well as the system of professional and personal qualities of a mentor.