Estimating turbulent velocities in the elliptical galaxies NGC 5044 and NGC 5813

The interstellar and intra-cluster medium in giant elliptical galaxies and clusters of galaxies is often assumed to be in hydrostatic equilibrium. Numerical simulations, however, show that about 5-30% of the pressure in a cluster is provided by turbulence induced by, for example, the central AGN and merger activity. We aim to put constraints on the turbulent velocities and turbulent pressure in the ICM of the giant elliptical galaxies NGC 5044 and NGC 5813 using XMM-Newton RGS observations. The magnitude of the turbulence is estimated using the Fe XVII lines at 15.01 A, 17.05 A, and 17.10 A in the RGS spectra. At low turbulent velocities, the gas becomes optically thick in the 15.01 A line due to resonant scattering, while the 17 A lines remain optically thin. By comparing the (I(17.05)+I(17.10))/I(15.01) line ratio from RGS with simulated line ratios for different Mach numbers, the level of turbulence is constrained. The measurement is limited by systematic uncertainties in the atomic data, which are at the 20-30% level. We find that the line ratio in NGC 5813 is significantly higher than in NGC 5044. This difference can be explained by a higher level of turbulence in NGC 5044. The high turbulent velocities and the fraction of the turbulent pressure support of >40% in NGC 5044, assuming isotropic turbulence, confirm that it is a highly disturbed system, probably due to an off-axis merger. The turbulent pressure support in NGC 5813 is more modest at 15-45%. The (I(17.05)+I(17.10))/I(15.01) line ratio in an optically thin plasma, calculated using AtomDB v2.0.1, is 2 sigma above the ratio measured in NGC 5044, which cannot be explained by resonant scattering. This shows that the discrepancies between theoretical, laboratory, and astrophysical data on Fe XVII lines need to be reduced to improve the accuracy of the determination of turbulent velocities using resonant scattering.Comment: 11 pages, 5 figures, accepted for publication in A&

Generation of Plasmid DNA Expressing Species-Specific Horse VEGF164 and FGF2 Factors for Gene Therapy

© 2016, Springer Science+Business Media New York.In this study, we have generated a dual expression cassette plasmid DNA (pDNA) construct containing the species-specific horse (Equus caballus) codon optimized sequence encoding potent pro-angiogenic vascular endothelial growth factor (VEGF164) and basic fibroblast growth factor (FGF2) under eukaryotic promoters (EF-1α and CMV promoters, respectively). We have demonstrated effective and simultaneous recombinant proteins expression in vitro. Resulting pDNA is suitable for potential gene therapy applications in horses

Integral estimation of systemic inflammatory response under sepsis

Currently, the most significant mediators of the systemic inflammatory response (SIR), specific to the development of critical states in sepsis, have the chaotic changes of concentrations in the blood. The solution to the problem is using integral indicators. A scoring scale of the SIR (0–16 points) is proposed based on the determination in the blood plasma of CRP, TNF-α, IL-6, IL-8 and IL-10. The scale was used in the survey of 167 patients with a diagnosis of sepsis (43 patients with sepsis according to definitions of “Sepsis-1 or 2” and 124 patients with sepsis according to the criteria of “Sepsis-3”); septic shock was verified in 31 cases and in 48 cases lethal outcomes were recorded. The association of SIR with critical complications of sepsis was revealed, especially under acute septic shock and in cases of a “second wave” (days 5–7) of critical complications. In contrast, prolonged/ subacute sepsis (more than 14 days) under tertiary peritonitis is characterised by a lesser dependence of the criticality of the state on the severity of SIR. The proposed scale is an open system and allows you to modify the range of used particular indicators that are compatible by pathogenetic and diagnostic significance. © 2020, Slovak Academy of Sciences. All rights reserved.The work was carried out within the framework of the IIP UrB RAS theme No АААА-А18-118020590108-7

Deep Chandra observation and numerical studies of the nearest cluster cold front in the sky

We present the results of a very deep (500 ks) Chandra observation, along with tailored numerical simulations, of the nearest, best resolved cluster cold front in the sky, which lies 90 kpc (19 arcmin) to the north-west of M 87. The northern part of the front appears the sharpest, with a width smaller than 2.5 kpc (1.5 Coulomb mean free paths; at 99 per cent confidence). Everywhere along the front, the temperature discontinuity is narrower than 4–8 kpc and the metallicity gradient is narrower than 6 kpc, indicating that diffusion, conduction and mixing are suppressed across the interface. Such transport processes can be naturally suppressed by magnetic fields aligned with the cold front. Interestingly, comparison to magnetohydrodynamic simulations indicates that in order to maintain the observed sharp density and temperature discontinuities, conduction must also be suppressed along the magnetic field lines. However, the northwestern part of the cold front is observed to have a non-zero width. While other explanations are possible, the broadening is consistent with the presence of Kelvin–Helmholtz instabilities (KHI) on length-scales of a few kpc. Based on comparison with simulations, the presence of KHI would imply that the effective viscosity of the intracluster medium is suppressed by more than an order of magnitude with respect to the isotropic Spitzer-like temperature dependent viscosity. Underneath the cold front, we observe quasi-linear features that are ∼10 per cent brighter than the surrounding gas and are separated by ∼15 kpc from each other in projection. Comparison to tailored numerical simulations suggests that the observed phenomena may be due to the amplification of magnetic fields by gas sloshing in wide layers below the cold front, where the magnetic pressure reaches ∼5–10 per cent of the thermal pressure, reducing the gas density between the bright features

NMR paramagnetic probing of polymer solutions using manganese(II) ions

© 2017, Pleiades Publishing, Ltd. Nuclear magnetic relaxation studies show that manganese(II) ions can serve as paramagnetic probes for investigation of aqueous solutions of polyelectrolytes (polystyrene sulfonate and polyethylenimine) and their mixtures. The analysis of the measured rates of spin–lattice (R 1 ) and spin–spin (R 2 ) relaxations reveals the differences in the binding character of manganese(II) ions with polystyrene sulfonate and polyethylenimine. In a mixture of the polymers in acidic and neutral media, manganese(II) forms two types of ternary complexes. Using the suggested method for definition of the hydration degree of a coordination sphere of the bound probe ions, the number of water molecules in the first sphere of the polymer-bound manganese(II) ions is found on the basis of the value of the R 2 /R 1 ratio

The influence of executive capacity on selective attention and subsequent processing

Recent investigations that suggest selective attention (SA) is dependent on top-down control mechanisms lead to the expectation that individuals with high executive capacity (EC) would exhibit more robust neural indices of SA. This prediction was tested by using event-related potentials (ERPs) to examine differences in markers of information processing across 25 subjects divided into two groups based on high vs. average EC, as defined by neuropsychological test scores. Subjects performed an experimental task requiring SA to a specified color. In contrast to expectation, individuals with high and average EC did not differ in the size of ERP indices of SA: the anterior Selection Positivity (SP) and posterior Selection Negativity (SN). However, there were substantial differences between groups in markers of subsequent processing, including the anterior N2 (a measure of attentional control) and the P3a (an index of the orienting of attention). EC predicted speed of processing at both early and late attentional stages. Individuals with lower EC exhibited prolonged SN, P3a, and P3b latencies. However, the delays in carrying out SA operations did not account for subsequent delays in decision making, or explain excessive orienting and reduced attentional control mechanisms in response to stimuli that should have been ignored. SN latency, P3 latency, and the size of the anterior N2 made independent contributions to the variance of EC. In summary, our findings suggest that current views regarding the relationship between top-down control mechanisms and SA may need refinement

Situational problems as a means for forming the professional competencies of university students

© 2015 by the author(s). The purpose of this article aims to study the problem of forming students' competencies during the professional training in the university. The paper demonstrates a methodology for the development and application of situational problems as an effective means of forming the professional competencies of university students. The basis of the presented work is the ideas of the competence-based and the activity-based approaches, expert evaluation of the university students' educational activity. The article describes the technology for developing the situational problems, based on the analysis of the professional roles. This article is intended for educators, researchers, and heads of educational institutions that are into the formation and diagnostics of university students' professional competencies

Information competence structure and content of the higher school students

© 2015, Mediterranean Center of Social and Educational Research. All rights reserved. For free orientation in the flow of information people should possess information competence as one of the components of professionalism. In this regard, the article reveals the structure and content of the information competence of students, including motivational and values, cognitive, activity, communicative and health saving components that are in relationships and are aimed at ensuring the integrity and continuity of the process of students’ information competence forming in conditions of modern high school.The article also describes the problem of the teachers’ functions’ expansion involved in this process. The article can be recommended for use in modern practice of educational institutions, as well as in the system of teacher training