Urban geochemical changes and pollution with potentially harmful elements in seven Russian cities

This paper presents results of an analysis of potentially harmful elements (PHEs, Pb, Zn and Cu) and conservative element (CE, Fe) concentrations in urban surface deposited sediment (USDS). The study was conducted in seven large Russian cities located in different geographic and climatic zones, and in territories with different geology and anthropogenic pressures: Chelyabinsk, Magnitogorsk, Nizhniy Novgorod, Nizhniy Tagil, Rostov-on-Don, Tyumen, and Ufa. The initial geochemical baseline relationships between PHEs and CE concentrations in the USDS were reconstructed for each city applying an approach based on linear weighted fitting of PHE as a function of CE with lower weights assigned to more polluted samples. The reconstructed average initial baseline Pb, Cu, and Zn concentrations varied between 17–52, 25–196, and 91–413 mg kg−1, respectively. Several new criteria for assessing the degree of geochemical transformation and pollution of the urban environment, such as the percentage of polluted samples, average pollutant concentration in polluted samples, and weighting degree index δ, were suggested and compared with common criteria, such as the PHE concentration and the geo-accumulation index. The environmental rank of a city significantly differed depending on whether the criterion for ranking was total PHE pollution or changes in comparison with the initial geochemical baseline. © 2020, The Author(s).Russian Science Foundation, RSF: 18-77-10024The study was supported by Russian Science Foundation (grant No. 18-77-10024)

Slope stability monitoring from microseismic field using polarization methodology

International audienceNumerical simulation of seismoacoustic emission (SAE) associated with fracturing in zones of shear stress concentration shows that SAE signals are polarized along the stress direction. The proposed polarization methodology for monitoring of slope stability makes use of three-component recording of the microseismic field on a slope in order to pick the signals of slope processes by filtering and polarization analysis. Slope activity is indicated by rather strong roughly horizontal polarization of the respective portion of the field in the direction of slope dip. The methodology was tested in microseismic observations on a landslide slope in the Northern Tien-Shan (Kyrgyzstan)

ПЕДАГОГІЧНІ УМОВИ ВИКОРИСТАННЯ АКТИВНИХ МЕТОДІВ НАВЧАННЯ У ПРОЦЕСІ ПІДГОТОВКИ ФАХІВЦІВ МЕДИЧНОГО ПРОФІЛЮ

The aim of the work – to analyze the essence of active methods of teaching, the peculiarities of their use in the educational process and to determine the pedagogical conditions that contribute to the improvement of the quality of medical specialists training.The main body. The article presents an analysis of the active learning methods and defines the special features of their use to improve quality of the educational process and training of future specialists. Besides of that, we substantiate pedagogical conditions of employment of the active learning methods, particularly in the training of specialists of medical profile. The authors consider that the introduction of such methods is one of the most promising way to improve the training of future professionals, including doctors, and gives necessary knowledge and practical skills to them. The article determines the main pedagogical conditions of the active learning methods in the training of interns such as the identity and pedagogical skills of a teacher and the diversification of forms and methods of training.Conclusion. We are sure that the method of discussion, the didactic games, the method of situational analysis (case method), the multimedia learning and the method of simulation are the most effective for a professional development of interns.Мета роботи – проаналізувати сутність активних методів навчання, особливості їх використання в освітньому процесі та визна­чити педагогічні умови, що сприяють підвищенню якості підготовки фахівців медичного профілю.Основна частина. У статті наводиться аналіз активних методів навчання, визначаються особливості їх використання з метою підвищення якості освітнього процесу та підготовки майбутніх фахівців. Обґрунтовуються педагогічні умови використання активних методів навчання, зокрема у підготовці фахівців медичного профілю. Визначається, що серед основних педагогічних умов є, по-перше, особистість викладача та рівень його педагогічної майстерності, а по-друге – урізноманітнення форм та методів навчання і безпосереднє упровадження активних методів в освітній процес.Висновок. Підкреслюється, що найбільш ефективний вплив на професійний розвиток лікаря-інтерна, як компетентної особистості та конкурентоспроможного фахівця, здійснюється завдяки застосуванню в освітньому просторі ВНЗ таких активних методів, як: навчання в дискусії, дидактичні ігри, метод ситуаційного аналізу (кейс-метод), мультимедійні засоби навчання, метод моделювання ситуацій (симуляційне навчання) та ін

Luminosity and mass function of galactic open clusters: I. NGC 4815

We present deep V and I photometry for the open cluster NGC 4815 and four surrounding Galactic fields down to a limiting magnitude $V\sim25$. These data are used to study cluster spatial extension by means of star counts, and to derive the luminosity (LF) and mass function (MF). The radius turns out to be $3.6\pm0.3 arcmin$ at V=19.0 level, whereas the mass amounts at $880\pm230 m_{\odot}$ down to V=20.8. From the color-magnitude diagram, we obtain the LFs in the V and I bands, using both the standard histogram and an adaptive kernel. After correction for incompleteness and field star contamination, the LFs have been transformed into the present day mass functions (PDMF). The PDMFs from the V and I photometry can be represented as a power-law with a slope $\alpha = 3.1\pm0.3$ and $\alpha = 2.9\pm0.3$ (the \cite{salp55} MF in this notation has a slope $\alpha = 2.35$) respectively, in the mass range $2.5 \leq \frac{m}{m_{\odot}} \leq 0.8$. Below this mass, the MF cannot be considered as representative of the cluster IMF, as it is the result of the combined effect of strong irregularities in the stellar background, probable internal dynamical evolution of the cluster and/or interaction of the cluster with the dense Galactic field. Unresolved binaries and mass segregation can only flatten the apparent derived IMF, so we expect that the real IMF must be steeper than the quoted slope by an unknown amount.Comment: 12 pages, 10 eps figures, in press in Astronomy and Astrophysic

Double difiusion in Ar-N2 Binary gas system at the constant value of temperature gradient

An experimental study of the diffusion-gravitational convection transition boundary in an Ar-N2 binary system at different pressures and a constant temperature gradient is performed. It is shown that the diflusion is replaced by the gravitational convection at a pressure p 0:5 MPa. In terms of the stability theory, a perturbation boundary line is determined, dividing the Rayleigh numbers plane into the regions of the diflusion and the convective mass transfer. The experimental data agree well with the theoretical values