Amorphous Hydrogenated Carbon Films with Diamond-Like and Polymer-Like Properties

Results of the study of structural features and optical properties of thin films of amorphous hydrogenated carbon (a-C:H) films prepared by plasma-activated chemical vapor deposition of various hydrocarbon precursors are reviewed. The effect of different factors on the rate of a-C:H films deposition in a DC glow discharge with the magnetron plasma localized near the anode such as voltage, discharge power, gas pressure, relative content of an inert gas in the mixture with a hydrocarbon and other is analyzed. It is shown that the refractive index of a-C:H films can be changed in the interval 2.35–1.55 by increasing the deposition rate and the choice of the appropriate hydrocarbon precursor. The features of the vibration spectra of the diamond-like and polymer-like films are discussed. The correlations of the structural peculiarities and of the optical absorption edge, gap width, and conductivity as well as the absorption spectra in visible region and the ratio of the fundamental bands in Raman scattering spectra are estimated. Examples of using the optical properties of the a-C:H films are given

Використання даних MODIS MCD45 для оцінки площ вигорілих територій бореального підпоясу європейської частини Росії

Дані про площі вигорілих територій є якісним матеріалом для ретроспективної оцінки ролі пірогенного фак- тора. Одним із джерел такої інформації є дані сенсора MODIS. У роботі була проведена оцінка якості даних MODIS MCD45. За задовільними результатами був проведений просторово‑часовий аналіз осередків виник- нення та поширення пожеж на території бореального підпоясу Європейської частини Росії. Виявлено тенденції пірогенного фактора в цілому, а також за суб’єктами і ландшафтними зонами

Adolescents’ idea of the parental participation in early career choice

Background. Early career choice is a developmental task at the adolescent age (D.B. Elkonin, I.S. Kon, D.I. Feldstein). Diversified educational system in Russia makes it objectively possible to implement various trajectories of professional development in the transition from childhood to adulthood (L.A. Golovei, O.A. Karabanova, N.S. Pryazhnikov). The paper is devoted to the study of parental involvement in career choice in the context of the modernization of the Russian educational system. The scheme of Personal Career Plan (PCP) is a substantive procedural model of career choice (N.S. Pryazhnikov). The adolescent PCP development is studied as a process that is realized through the interaction between the adolescents and their parents and is understood as the co-adjustment process (G.V. Burmenskaya) of the efforts of adolescent and parents in solving the task of building the PCP. The collaboration of parents and adolescents is determined by child-parent relationship (CPR), development of personal autonomy, autonomy of adolescent in CPR. There is lack of research devoted to the study of parent-child relationship at the stage of the career choice, types of parental involvement in the adolescent’s PCP g. Objective. The objective of the research is to study the correlation between parental involvement in career choice by adolescents and emotional autonomy in CPR in adolescence (according to adolescents). Design. The paper presents the results of the authors’ empirical research parental involvement (according to adolescents). The study was conducted in 2016-2017 and represents a part of a broader research of the conditions and factors for PCP in the Russian adolescents. The sample included 167 adolescents of Moscow high schools from 14 to 18 y.o. The techniques included modified “Parent Career Behavior Checklist” (Keller, Whiston, 2008), and modified “Emotional Autonomy scale” (EAS) (Steinberg, 1986) (author’s adaptation). Findings. The obtained data allowed to conclude that the parental involvement in career choice is quite possible. Five groups of adolescents with different level of parental (mothers’ and fathers’) support in career choice (according to adolescents) were distinguished. The results confirm the correlation of adolescent’s emotional autonomy in CPR and the features of parental involvement in career choice (acoording to adolescents). Conclusion. The hypothesis of the correlation of the parental involvement and the emotional autonomy in CPR was confirmed. The nonlinear character of the relationship between parental involvement and emotional autonomy of adolescents in the CPR has been revealed

SILICA GEL WITH COVALENTLY IMMOBILIZED IMIDAZOLIUM SALT AS A NEW STATIONARY PHASE FOR ION CHROMATOGRAPHY

This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation (project no. 4.4892.2017). This work was accomplished with the use of scientific equipment of the Collective Employment Centre “Ecoanalytical Centre”, Kuban State University

Structure-Based Rational Design of Small α-Helical Peptides with Broad-Spectrum Activity against Multidrug-Resistant Pathogens

A series of small (7–12 mer) amphipathic cationic peptides were designed and synthesized to create short helical peptides with broad-range bactericidal activity and selectivity toward the bacterial cells. The analysis identified a lead 12-mer peptide 8b with broad-spectrum activity against Gram-positive (MIC = 3.1–6.2 μg/mL) and Gram-negative (MIC = 6.2–12.5 μg/mL) bacteria and selectivity toward prokaryotic versus eukaryotic cells (HC50 = 280 μg/mL, \u3e75% cell viability at 150 μg/mL). The rapid membranolytic action of 8b was demonstrated by a calcein dye leakage assay and confirmed using scanning electron microscopy. According to circular dichroism and NMR spectroscopy, the peptides have an irregular spatial structure in water. A lipid bilayer induced an amphipathic helix only in 12-mer peptides, including 8b. Molecular dynamics simulations provided detailed information about the interaction of 8b and its closest analogues with bacterial and mammalian membranes and revealed the roles of particular amino acids in the activity and selectivity of peptides

Broad-spectrum Activity of Membranolytic Cationic Macrocyclic Peptides Against Multi-drug Resistant Bacteria and Fungi

The emergence of multidrug-resistant (MDR) strains causes severe problems in the treatment of microbial infections owing to limited treatment options. Antimicrobial peptides (AMPs) are drawing considerable attention as promising antibiotic alternative candidates to combat MDR bacterial and fungal infections. Herein, we present a series of small amphiphilic membrane-active cyclic peptides composed, in part, of various nongenetically encoded hydrophilic and hydrophobic amino acids. Notably, lead cyclic peptides 3b and 4b showed broad-spectrum activity against drug-resistant Gram-positive (MIC = 1.5–6.2 µg/mL) and Gram-negative (MIC = 12.5–25 µg/mL) bacteria, and fungi (MIC = 3.1–12.5 µg/mL). Furthermore, lead peptides displayed substantial antibiofilm action comparable to standard antibiotics. Hemolysis (HC50 = 230 µg/mL) and cytotoxicity (\u3e70 % cell viability against four different mammalian cells at 100 µg/mL) assay results demonstrated the selective lethal action of 3b against microbes over mammalian cells. A calcein dye leakage experiment substantiated the membranolytic effect of 3b and 4b, which was further confirmed by scanning electron microscopy. The behavior of 3b and 4b in aqueous solution and interaction with phospholipid bilayers were assessed by employing nuclear magnetic resonance (NMR) spectroscopy in conjunction with molecular dynamics (MD) simulations, providing a solid structural basis for understanding their membranolytic action. Moreover, 3b exhibited stability in human blood plasma (t1/2 = 13 h) and demonstrated no signs of resistance development against antibiotic-resistant S. aureus and E. coli. These findings underscore the potential of these newly designed amphiphilic cyclic peptides as promising anti-infective agents, especially against Gram-positive bacteria

Determination of Influence of the oil production factor on the Russian economy

The article describes the results of statistical analysis and forecasting of the oil market of the Russian Federation. An analysis of the dependence of monetary aggregates on factors of oil production, export and the price of oil has been conducted using three-factor mode

PERMITTIVITY DISPERSION FEATURES OF A NEMATIC LIQUID CRYSTAL WITH QUANTUM DOTS

Subject of Research. The paper deals with research of dielectric properties of suspensions for a nematic liquid crystal (LC) with positive dielectric anisotropy Δε = 10.5, doped with semiconductor quantum dots (QDs) CdSe / ZnS, and dependence on their concentration in the range of 0.05-0.3 wt. %. Methods. The studies were carried out by the method of dielectric spectroscopy. A special flat titanium cell with the distance between the electrodes equal to 250 μm was used for the measurement. The voltage was applied to the electrodes. The dispersion of parallel and normal parts of the real and imaginary components of the dielectric permittivity was measured in the range from 50 Hz to 6.5 MHz at the orienting magnetic field equal to 4 • 105 A / m applied to a cell. Main Results. Deviation of the permittivity spectra of suspensions with QDs concentration growth was observed from a spectrum of the pure LC. It was caused by losses of free ions on the conductivity at frequencies below 103 Hz. The shift of a peak in the suspension spectrum at frequencies above 106 Hz is associated with relaxation of the LC molecules orientation. It has been shown that lowering in the range of 103 -104 Hz with concentration increasing up to 0.3 wt. % did not exceed 4%. Practical Relevance Obtained results give the possibility to explain the change in macroscopic properties of the liquid crystal as a result of doping