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Antiviral activity of antisense oligodeoxyribonucleotides with phosphorothioate or mesyl phosphoramidate internucleotidic groups targeting the main capsid protein VP72 mRNA of the African swine fever virus (ASFV), either in a free form with Lipofectamine 3000 transfection or in the form of ionic complexes with amino-modified mesoporous silicon dioxide nanoparticles, has been evaluated in Vero cells infected with ASFV. Relatively high cytotoxicity of oligonucleotide nanocomplexes for Vero cells at concentrations above 500 nM was detected. Two sequences of antisense oligonucleotides were identified, which reduced the virus titer by an order of magnitude at 500 nM. The antiviral effect of nanocomplexes exceeded that of free oligonucleotides in the presence of Lipofectamine 3000, which indicates a more efficient delivery of nanocomplexes to the cells. Antisense oligonucleotides able to reduce the replication of ASFV were hitherto unknown from the literature. The obtained data can be used as a starting point for further research on the development of oligonucleotide-based antiviral drugs against the African swine fever virus.

Aperture shapes in modern large and forthcoming extremely large telescopes (ELTs), with effective light-gathering sizes more than D ∼ 10 m, differ significantly from the desirable circular one. They deliver specific point spread functions, which may also differ notably from that of the fine structure of the classical Airy pattern. The optical power of such a telescope can be changed notably compared with a circular aperture with the same area. The presence of atmospheric optical turbulence complicates the effect additionally and makes it seeing- and wavelength-dependent. So, what is the impact of a non-circular pupil on telescope exploitation? It concerns the efficiency, which is an important point, especially for instruments of such a class. In this research an attempt is made to assess the values of these changes in the context of the Keck, HDRT, GMT, TMT and ELT telescopes. Relative performance characteristics (integral contrast and signal-to-noise ratio, S/N) of the telescopes, working in the seeing-limited regime, under a range of plausible turbulence conditions, for a wide (from UV to mid-IR) spectral region are obtained. The partial role of central obscuration is assessed. The effect of adaptive optics implementation in this context is also analysed. It is shown that, for instance, maximal S/N degradation due to the non-circularity of the pupil shape can be as much as $\sim 6~{{\ \rm per\ cent}}$ (TMT) to $30~{{\ \rm per\ cent}}$ (HDRT), depending on the telescope and observational mode. The numbers are comparable with or may even substantially exceed the losses that could be caused by the other parameters (e.g. residual wave-front error, optical transmittance) relevant to the quality of the optical system.

KEEN The factors associated with the spread and persistence of African swine fever (ASF) in the Caucasus region remain to be fully identified. It is assumed that large naive populations of domestic free-ranging and wild pigs are critical to disease transmission and maintenance. Nonetheless, 11 years since its epidemic introduction into the region in 2007, ASF virus (ASFV) is still circulating, suggesting that an endemic cycle has been established based on contact between free-ranging domestic pigs and wild pigs, and that native Ornithodoros ticks probably serve as reservoirs for the virus. Therefore, research is required to gather information on the epidemiological status of ASF in the Caucasus region, focusing particularly on understanding modes of ASFV spread and persistence in this new virus environment. The authors established an ASFV survey targeting domestic pigs in the Tavush province of northern Armenia, an area of the country considered to be at high risk of disease incursion/occurrence. All tested samples collected for this survey were negative for ASF. The probability of observing no reactors by antibody enzyme-linked immunosorbent assay in a sample of this size (n = 1,506) from a population with an estimated disease prevalence of 1% is very low (< 0.0001). Therefore, it is possible but very unlikely for ASFV to be present among domestic pigs in the Tavush province region.

By the method of Hankel integral transformation, discontinuous solutions of equations of the axisymmetric elasticity theory are constructed for a piecewise homogeneous uniform layered space obtained by alternately joining two heterogeneous layers of equal thickness and whose junction contains a periodic system of parallel circular disk-shaped defects. On the basis of the solutions found, as examples, the governing systems of integral equations with Weber–Sonin kernels are presented for two cases: with defects in the form of absolutely rigid disk-shape inclusions and circular cracks. Using rotation operators, the governing systems of equations, in both cases, are reduced to a singular integral equation of the second kind, which is solved by the method of mechanical quadratures. Simple formulas for determining the rigid-body displacement of inclusions and crack opening are obtained.

The article considers the contact problem of indentation of an absolutely rigid stamp with dry friction into one of the edges of an interfacial finite crack located in a piecewise homogeneous elastic plane. The governing system of equations for the problem is derived in the form of a system of three singular integral equations with respect to the normal contact pressure under the stamp and dislocation components of the displacements of the crack edge points. The exact solution is constructed. The behavior of contact stresses near the end points of a crack is studied depending on the ratio of the elastic characteristics of heterogeneous materials of half-planes that formed a piecewise-homogeneous plane.

Mercuration-demercuration of 2-propyl-2-ynyloxymethyltetrahydrofuran with various nucleophiles has been investigated. Formation of products of hydration, alkylation at the substituted carbon atom of the triple bond, subsequent prototropic isomerization or intramolecular cyclization (giving diastereomeric dihydrofuran derivatives), and demercuration by hydrochloric acid has been demonstrated.

An achiral nickel complex with a Schiff base derived from glycine was alkylated with alkyl halides under conditions of asymmetric phase-transfer catalysis. The chiral tetraol (R)-BIMBOL was employed as a catalyst. The enantiomeric purity of the alkylation products was up to 88%. Subsequent decomposition of the complexes afforded the corresponding a-amino acids.

Electro-physical parameters of super-thin basalt fiber (STBF) from Armenian basalt rocks are measured before and after hydrochloric acid treatment. It is shown that specific resistance and dielectric parameters of super-thin basalt fiber change essentially after hydrochloric acid treatment. The temperature dependence of these parameters was studied too. The probable cause of the change is an increase in the total amount of pores and modification of the share of pores of various sizes in STBF, followed by an increase of absorption of water molecules from the ambient medium. The results (in both alternating and direct electric fields) are interpreted within the framework of the dipole-relaxation mechanism of the polarization of water molecules in STBF pores.

(S)- and (R)-BIMBOL were efficient PT catalysts of asymmetric Michael addition of prochiral Ni-PBP-Gly (1) to acrylic esters and malonic esters to Ni-PBP-Δ-Ala (2) correspondingly. The salient feature of the catalysis is opposite configurations of Glu prepared via the two paths with BIMBOL of the same configuration and a perspective novel catalytic procedure for the synthesis of Gla derivatives.

The influence of hydrochloric or sulphuric acid treatment on the electro-physical properties of superthin basalt fiber (STBF) made from Armenian basalt rocks was studied. Specific electric resistance for direct and alternating currents, dielectric parameters of e, and e,, were measured. It is shown that specific resistance and dielectric parameters of super-thin basalt fiber change essentially after hydrochloric or sulphuric acid treatment. The temperature dependences of these parameters were studied, too, and their non–monotonic behavior was observed. The probable variation of mentioned STBF parameters is explained by different water absorption capacity of pores as a result of acid treatment.

The catalytic performance of the Li salt of ( S )- or ( R )-3,3′-bis[bis-(phenyl)hydroxymethyl]-2,2′-dihydroxy-dinaphthalene-1,1′ (BIMBOL) in asymmetric Michael additions of malonic acid derivatives and toluedine has been studied. Nitrostyrene and cyclohex-2-enone were chosen as Michael acceptors. Efficient asymmetric C–C and C–N bond formations with ee’s of up to 95% at room temperature were observed. A transition state model of the malonic ester addition to cyclohex-2-enone has been proposed based on the molecular structure of the acetone solvate of BIMBOL. The impact of the catalyst self-association on its performance is also discussed.

We have shown experimentally that by choosing the value of the direct component of the discharge current and the frequency of modulation of alternating component it is possible to control the coupling of modules in a multi-module gas-discharge CO2-laser with series connection of modules having common resonator and gas space. The depth of intermodulation was measured when one of modules is supplied with only direct current, while other one by the modulated.

We explore the efficiency and robustness of population transfer in two-state systems by adiabatic passage (i) when the driving pulse is optimally designed in order to lead to parallel adiabatic passage or (ii) with a linear chirping. We show how one could practically implement the corresponding designs of the pulses in the spectral domain. We analyze the robustness of the two shapings taking into account fluctuations of the phase, amplitude, and the area of the pulse. We show the overall superiority of the parallel adiabatic passage especially when one faces the issue of a pulse area that is not well known. We show that the robustness of parallel adiabatic passage is not improved when it is complemented by a correcting field that cancels out the nonadiabatic losses.

We demonstrate experimentally and theoretically the intensity-invariant scaling formula of coherent control of two-photon absorption as a function of pulse-shape parameters of ultrafast laser field in the strong-interaction regime.

Automated differential lidar set for measurement of atmospheric gases small concentration is developed, created and tested on the bases of Optical Parametric Oscillator (OPO), tunable in middle infrared (IR) range. Measurable sensitivity accuracy obtained for atmospheric methane is not less than I ppm. Being smoothly tunable in the wavelength range of 1.4 ÷ 4.2um with the spectral bandwidth of 3cm-1 (for 1.4÷1 .8um and 2.9÷4.2um) and pulse energy up to 40mJ, the OPO irradiation allows measurement of gas concentrations in an open atmosphere up to 5km. If required computer controlled Fabry-Perot etalon (FPE) insertion into the resonator is provided to narrow the bandwidth up to O.6cm-1 . Construction of the OPO allows also radiation wavelength stepwise change (pulse to pulse) with a smooth regulation from 0 to 12cm-1 that is necessary to carry out gas concentration measurement by the method of differential absorption with one laser. Lidar set is equipped with a self-regulated system, tuned at the absorption line of the gas under investigation that is initially installed into the system.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We explore the three-photon triple ionization from the ground state of Li with short wavelength free electron lasers. We calculate and discuss the cross sections used in the relevant rate equations and the dependence of the ion yields on laser intensity and pulse duration. In addition to the three-photon 3e ejection we also discuss two- and three-photon 2e ejection in Li+, which occurs as a by-product in the sequence of the channels active in the overall interaction. We conclude by assessing the requirements for the observability of the above-mentioned direct three-photon multielectron processes.