A Uniform Contribution of Core-Collapse and Type Ia Supernovae to the Chemical Enrichment Pattern in the Outskirts of the Virgo Cluster

We present the first measurements of the abundances of $\alpha$-elements (Mg, Si, and S) extending out to beyond the virial radius of a cluster of galaxies. Our results, based on Suzaku Key Project observations of the Virgo Cluster, show that the chemical composition of the intra-cluster medium is consistent with being constant on large scales, with a flat distribution of the Si/Fe, S/Fe, and Mg/Fe ratios as a function of radius and azimuth out to 1.4 Mpc (1.3 $r_{200}$). Chemical enrichment of the intergalactic medium due solely to core collapse supernovae (SNcc) is excluded with very high significance; instead, the measured metal abundance ratios are generally consistent with the Solar value. The uniform metal abundance ratios observed today are likely the result of an early phase of enrichment and mixing, with both SNcc and type Ia supernovae (SNIa) contributing to the metal budget during the period of peak star formation activity at redshifts of 2-3. We estimate the ratio between the number of SNIa and the total number of supernovae enriching the intergalactic medium to be between 12-37%, broadly consistent with the metal abundance patterns in our own Galaxy or with the SNIa contribution estimated for the cluster cores.Comment: accepted for publication in ApJ

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&

Effect of GDNF on Morphology, Proliferation, and Phagocytic Activity of Rat Neonatal Cortex Isolated Microglia

© 2016, Springer Science+Business Media New York.Microglia are the main defenders of the central nervous system and at the same time are involved in the pathogenesis of various neurological disorders. Microglia hyperactivity or phagocytic impairment exacerbates degenerative processes in nervous tissue leading to further loss of function. A variety of factors and cytokines may modify microglia function. In our study, it was shown that glial cell line-derived neurotrophic factor (GDNF), a well-known neuroprotective molecule, decreases phagocytic activity of microglia in vitro model of spinal cord injury. Recombinant adenovirus encoding GDNF (Ad5-GDNF) transfected microglia have shown the same effect and can be potentially used as a therapeutic agent in case of neurotrauma due to its debris phagocytic and GDNF-associated neuroprotective role

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

Azimuthally Resolved X-Ray Spectroscopy to the Edge of the Perseus Cluster

We present the results from extensive, new observations of the Perseus Cluster of galaxies, obtained as a Suzaku Key Project. The 85 pointings analyzed span eight azimuthal directions out to 2 degrees = 2.6 Mpc, to and beyond the virial radius r_200 ~ 1.8 Mpc, offering the most detailed X-ray observation of the intracluster medium (ICM) at large radii in any cluster to date. The azimuthally averaged density profile for r>0.4r_200 is relatively flat, with a best-fit power-law index of 1.69+/-0.13 significantly smaller than expected from numerical simulations. The entropy profile in the outskirts lies systematically below the power-law behavior expected from large-scale structure formation models which include only the heating associated with gravitational collapse. The pressure profile beyond ~0.6r_200 shows an excess with respect to the best-fit model describing the SZ measurements for a sample of clusters observed with Planck. The inconsistency between the expected and measured density, entropy, and pressure profiles can be explained primarily by an overestimation of the density due to inhomogeneous gas distribution in the outskirts; there is no evidence for a bias in the temperature measurements within the virial radius. We find significant differences in thermodynamic properties of the ICM at large radii along the different arms. Along the cluster minor axis, we find a flattening of the entropy profiles outside ~0.6r_200, while along the major axis, the entropy rises all the way to the outskirts. Correspondingly, the inferred gas clumping factor is typically larger along the minor than along the major axis.Comment: submitted to MNRA

ROLE OF HETERONUCLEAR COMPLEXES IN SOLUTIONS FOR METALLIZATION OF PLASTICS.

Metallization of plastics by chemical deposition of metals is an important technological process in production of circuit boards. The usual reducing agents are formaldehyde, borohydrides, hydrazine and its derivatives, and hypophosphites in alkaline media. Since most metal ions undergo hydrolysis in such media, they are converted into complex compounds. Salts of tartaric (H//4Tart) or citric (H//4Citr) acids, whose anions act as multidentate ligands, are used in solutions for chemical coppering and coating with nickel-cobalt and nickel-copper alloys. Heteronuclear complexes (HNC) may be formed in solutions containing two or more transition-metal salts. The authors studied the systems Cu(II)-Ni(II)-H//4Citr, Cu(II)-Co(II)-H//4Citr under the concentration conditions of copper baths. Using the NMR method, whereby formation of heteronuclear species can be recorded directly, the authors detected formation of a heteronuclear complex

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

DIAGNOSTIC EFFICACY OF C-REACTIVE PROTEIN AND IL-6 AS MARKERS OF SYSTEMIC INFLAMMATION

Currently, despite widespread use of the terms “systemic inflammation” (SI) and “systemic inflammatory response” (SIR), there are no generally accepted criteria for their verification. These processes are often identified (which is methodologically incorrect) and associated with an increase in pro-inflammatory mediators in the blood. However, SI is a complex process that requires integral criteria including assessment of SIR as reactivity level, and additional SI phenomena, such as microthrombosis, systemic alteration, and distress of the neuroendocrine system. At the same time, there is a need to assess individual CB indicators as a more affordable alternative for medical practice than the use of complex integral indicators. Our objective was to evaluate diagnostic efficacy of CRP and IL-6 levels as markers of acute and chronic systemic inflammation. The data of patients with acute critical conditions of infectious and non-infectious genesis were analyzed to study acute systemic inflammation (SI), data of patients with autoimmune diseases, chronic organ failure and other chronic destructive diseases were analyzed to study chronic systemic inflammation (ChrSI). SIR severity was evaluated by the calculation of an integral index – reactivity level (RL). Differentiation of the inflammatory process to either classical inflammation (CI), or systemic inflammation was carried out using the previously proposed scale of SI, verification of chronic systemic inflammation was performed by means of ChrSI scale. SI (or ChrSI) was revealed in all groups of patients, and the frequency of SI registration in patients with acute conditions increased with development of multi-organ failure. The frequency of SIR was higher in all groups, thus confirming inability to equate these disorders. ROC analysis showed that CRP level had poor diagnostic efficacy on the development of SI/ChrSI (AUC < 0.6), and IL-6 level had very good diagnostic value (AUC 0.8-0.9). The prognostic value of the markers for detecting the SIR was higher, with AUCIL-6 exceeding AUCCRP. Thus, IL-6 in many acute and chronic pathologies is sufficiently closer to integral indices than C-reactive protein with respect to diagnostic efficiency, and the dynamics of IL-6 in blood may be used to predict and evaluate complications associated with acute and chronic SI, as well as to prescribe and monitor the results of anticytokine therapy. © 2022, РНОИ

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

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