Single-chain compaction of long duplex DNA by cationic nanoparticles: modes of interaction and comparison with chromatin

The compaction of long duplex DNA by cationic nanoparticles (NP) used as a primary model of histone core particles has been investigated. We have systematically studied the effect of salt concentration, particle size, and particle charge by means of single-molecule observations-fluorescence microscopy (FM) and transmission electron microscopy (TEM)-and molecular dynamics (MD) simulations. We have found that the large-scale DNA compaction is progressive and proceeds through the formation of beads-on-a-string structures of various morphologies. The DNA adsorbed amount per particle depends weakly on NP concentration but increases significantly with an increase in particle size and is optimal at an intermediate salt concentration. Three different complexation mechanisms have been identified depending on the correlation between DNA and NPs in terms of geometry, chain rigidity, and electrostatic interactions: free DNA adsorption onto NP surface, DNA wrapping around NP, and NP collection on DNA chain.     

Consistent Determination of the Integral Humidity and Effective Optical Depth of the Atmosphere in the Millimeter Wavelength Range Using Wideband Radiometers

Radiophysics and Quantum Electronics - This paper proposes, and practically implements, a technique for finding equivalent frequencies, which are attributed to the atmospheric optical depths...     

Electrophysical Model of the Micro-Arc Oxidation Process

Russian Physics Journal - On the basis of the equivalent electrical circuit proposed by the authors, a mathematical model of the formation of protective coatings by the micro-arc oxidation method...     

A New Review of Excitation Functions of Hadron Production in pp Collisions in the NICA Energy Range

Physics of Particles and Nuclei Letters - Data on hadron multiplicities from inelastic proton-proton interactions in the energy range of the NICA collider have been compiled. The compilation...     

Analysis of the Results of Astroclimate Research at the Kara-Dag Radioastronomical Station in Crimea and the Possibilities for Reducing the Influence of the Atmosphere on Millimeter-Band Radioastronomical Observations

Journal of Experimental and Theoretical Physics - The results of astroclimate research at the Kara-Dag radioastronomical station (Crimea) from July 22 to September 21, 2017, are presented....     

Synthesis of Functionalized Diorganyl Selenides from Selenium Dihalides and Allylic Aromatic Compounds

Russian Journal of Organic Chemistry - Hitherto unknown addition and methoxyselenation reactions of selenium dihalides with methyl eugenol and allyl naphth-1-yl ether were studied. The addition and...     

Finite Gap Jacobi Matrices,III. Beyond the Szegő Class

Let \({\frak {e}}\subset {\mathbb {R}}\) be a finite union of ?+1 disjoint closed intervals, and denote by ω _j the harmonic measure of the j left-most bands. The frequency module for \({\frak {e}}\) is the set of all integral combinations of ω ₁,…,ω _? . Let \(\{\tilde{a}_{n}, \tilde{b}_{n}\}_{n=-\infty}^{\infty}\) be a point in the isospectral torus for \({\frak {e}}\) and \(\tilde{p}_{n}\) its orthogonal polynomials. Let \(\{a_{n},b_{n}\}_{n=1}^{\infty}\) be a half-line Jacobi matrix with \(a_{n} = \tilde{a}_{n} + \delta a_{n}\), \(b_{n} = \tilde{b}_{n} +\delta b_{n}\). Suppose

$\sum_{n=1}^\infty \lvert \delta a_n\rvert ^2 + \lvert \delta b_n\rvert ^2 <\infty $

and \(\sum_{n=1}^{N} e^{2\pi i\omega n} \delta a_{n}\), \(\sum_{n=1}^{N} e^{2\pi i\omega n} \delta b_{n}\) have finite limits as N→∞ for all ω in the frequency module. If, in addition, these partial sums grow at most subexponentially with respect to ω, then for z∈???, \(p_{n}(z)/\tilde{p}_{n}(z)\) has a limit as n→∞. Moreover, we show that there are non-Szeg? class J’s for which this holds.

     

Straw tube subsystem of the CBM muon detector

A straw tube subsystem design of the muon detector of the Compressed Baryonic Matter (CBM) experiment is described. Main parameters of the subsystem are shown. The muon detector performance evaluation results obtained using the Monte Carlo simulation are presented.     

Phase transformations in LnF3-(Ln, Zr)-ZrF4 systems, where Ln = Sm, Eu, Tm, Yb

Phase transformations in LnF₃-(Ln, Zr)-ZrF₄ systems (where Ln = Sm, Eu, Tm, Yb) in the temperature range 700-900 °C have been investigated by chemical and X-ray phase analyses, UV and IR spectroscopy. Synthesis conditions of nonstoichiometric samarium, europium, ytterbium and thulium fluorides, which are products of interaction between LnF₃ and Ln and original substances for the preparation of compounds such as LnZrF₆ are given. The crystal lattice of the fluorozirconates obtained is similar to the Yb₂₇F₆₄ superstructure. Thulium fluorozirconate (TmZrF₆), whose structure is indexed as the Tm₁₃F_32−δ superstructure of hexagonal system, is an exception. For all compounds obtained, the lattice parameters have been calculated and the absorption bands of IR spectra have been interpreted.     

One-Pot Syntheses of Functionalized Dihydrobenzoselenophenes and Selenochromans from Acetyl Eugenol and Selenium Dibromide. Rearrangement of 2-(Bromomethyl)-2,3-dihydro-1-benzoselenophene to Selenochromans

Russian Journal of Organic Chemistry - Efficient methods for the synthesis of new fused heterocyclic compounds have been developed on the basis of annulation–functionalization of acetyl...