Double Fe-impurity charge state in the topological insulator Bi2_2Se3_3

The influence of individual impurities of Fe on the electronic properties of topological insulator Bi$_2$Se$_3$ is studied by Scanning Tunneling Microscopy. The microscope tip is used in order to remotely charge/discharge Fe impurities. The charging process is shown to depend on the impurity location in the crystallographic unit cell, on the presence of other Fe impurities in the close vicinity, as well as on the overall doping level of the crystal. We present a qualitative explanation of the observed phenomena in terms of tip-induced local band bending. Our observations evidence that the specific impurity neighborhood and the position of the Fermi energy with respect to the Dirac point and bulk bands have both to be taken into account when considering the electron scattering on the disorder in topological insulators.Comment: 10 pages, accepted for publication in Applied Physics Letters, minor bugs were correcte

Effect of Epidemic Interference on the Performance of M-ASK, M-PSK and M-QAM Modulation Schemes

This article presents a study on the performance of different digital modulation systems in the presence of epidemic interference. This type of interference is caused by the fast increase in the number of users in a system at a given time. The epidemic interference can be modeled as a non-stationary stochastic process, which presents random power levels over time. In a previous work, the authors assessed the effect of the epidemic interference on the performance of BPSK, QPSK, and M-QAM systems. The present paper extends the previous results for MASK and M-PSK systems. Furthermore, numerical results from Monte Carlo simulations are presented for all evaluated digital modulation systems

Trigonal-bipyramidal Anion [Ph2Cl3Sn]- in the Structure of N-[(Diethylphosphoryl)methyl] piperidinium Diphenyltrichlorostannate(IV)

Crystal structure of N-(diethylphosphoryl)methyl-piperidinium diphenyltrichlorostannate(IV), C10H23NO3P+ C12H10Cl3Sn- has been determined, a = 11.416(2), b = 11.582(2), c = 12.491(2) Å, α = 69.82(2), β = 81.22(2), γ = 60.73(2)°, space group P1̅, 4493 reflections, R(F) = 0.0271, wR(F2) = 0.0712. The structure consists of isolated trigonal-bipyramidal anions and hydrogen-bonded dimers formed by cations. The impact of secondary Sn⋅⋅⋅Cl interactions on the geometry of complex anions is discussed

Evaluating the effectiveness of public health financing based on financial and non-financial indicators in terms of the knowledge economy

In conditions of the knowledge economy human capital, human value are the main factors of economic growth and prosperity of the state. Qualitative characteristics of human capital are indicators of public health. Therefore, one of the most important tasks of the state is to assess the effectiveness of financing public health expenditures. The methodological base of the research was the methods of system and economic analysis, mathematical statistics and decision optimization, which resulted in the identification of factors influencing the resource supply, availability and quality of public health. The formation of a comprehensive indicator of the effectiveness of the public health system based on the system of financial and non-financial indicators will allow to form numerically an assessment of the effectiveness of investments in public health and draw conclusions about the resources' provision, level of development, accessibility and quality of public health. The obtained results can be used in making effective public financial decisions, which allow to achieve an increase of accessibility and quality of health care, focusing on the human capital in conditions of knowledge economy.peer-reviewe

Photoemission of Bi2_2Se3_3 with Circularly Polarized Light: Probe of Spin Polarization or Means for Spin Manipulation?

Topological insulators are characterized by Dirac cone surface states with electron spins aligned in the surface plane and perpendicular to their momenta. Recent theoretical and experimental work implied that this specific spin texture should enable control of photoelectron spins by circularly polarized light. However, these reports questioned the so far accepted interpretation of spin-resolved photoelectron spectroscopy. We solve this puzzle and show that vacuum ultraviolet photons (50-70 eV) with linear or circular polarization probe indeed the initial state spin texture of Bi$_2$Se$_3$ while circularly polarized 6 eV low energy photons flip the electron spins out of plane and reverse their spin polarization. Our photoemission calculations, considering the interplay between the varying probing depth, dipole selection rules and spin-dependent scattering effects involving initial and final states explain these findings, and reveal proper conditions for light-induced spin manipulation. This paves the way for future applications of topological insulators in opto-spintronic devices.Comment: Submitted for publication (2013

Technology of critical thinking as a basis for interactive learning in graduate

The article describes the potential of the interactive methods based on the technology of critical thinking for the formation of professional competences in graduate economic trendsРассматривается возможность применения интерактивных методов на основе технологий критического мышления для формирования профессиональных компетенций у магистрантов экономических направлени

HFRS Morbidity Rates in the Territory of the Republic of Mordovia in 2009-2012

In the territory of Mordovia registered have been 321 cases of HFRS infection over the period of 2009-2012. Following the pattern of dynamics as regards HFRS epidemiological process, one can observe lingering tendency to the increment in morbidity rates, associated with the enhancement of quality and efficacy of clinical and laboratory diagnostics of the disease, as well as with activation of natural HFRS foci in the territory of Mordovia. Analysis of the gender-age structure of HFRS incidence has revealed that most liable to the infection is active, employable population, 20 to 50 years old. Morbidity rates for the male strata of the population are three times higher than for female. Epidemiological peculiarities of HFRS morbidity, characteristic of the Republic of Mordovia, are as follows: recurrence of epidemiological upsurge, autumn-winter seasonality, predominance of urban dwellers cohort and household route of infection