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The aim of the study was to identify and compare potential determinants of aminoglycoside resistance in gentamicin susceptible Burkholderia pseudomallei strains.Materials and methods. A bioinformatics analysis of whole genome shotgun sequences of three B. pseudomallei strains having different levels of sensitivity to gentamicin was carried out.Results and discussion. B. pseudomallei is intrinsically resistant to aminoglycosides. Such strains, as a rule, are not taken into account in the classical scheme of isolation and identification. At the same time, there were no significant differences in the clinical manifestations of melioidosis during infection with gentamicin-resistant and sensitive strains. In B. pseudomallei strains of different sequence types (ST70, ST948, and ST1566), point missense mutations were found in the genes of three efflux pumps of the RND family: AmrAB-OprA, BpeAB-OprB, BpeEF-OprC, and one with unknown functions, as well as in the gene aminoglycoside-6’-N-acetyltransferase AAC(6’)-III. All three strains had amino acid substitutions in the AmrA periplasmic linker: ARG160SER, Arg116Gln and Gly237Arg, Thr317Lys, respectively. In moderately sensitive strains (ST948 and ST1566), an identical Val222Met substitution was found in the repressor of the AmrAB-OprA operon, AmrR. It is likely that the intermediate level of sensitivity to gentamicin in the studied strains is mediated by the constitutive expression of the AmrAB-OprA operon, which partially compensates for the structural defects. It is also possible that a dinucleotide deletion in the AAC (6’)-III aminoglycoside-6’-N-acetyltransferase gene, as well as detected mutations in the homologues of the periplasmic linker (BPSL2234) of an uncharacterized efflux operon of the RND family, are involved in the loss of resistance to gentamicin.

Introduction. Valgus deformity of the Ist toe (hallux valgus) is a multicomponent deformity of the forefoot, which is the most common reason for visiting orthopedic surgeons. By now, there is idea that the hallux valgus development has a complex polyetiological and polypathogenetic nature. It makes a complex approach to treatment with the inclusion of methods focused on a holistic approach to body′s complex biomechanical systems in demand. One of such well-established and validated approach is osteopathy.The aim of the study is to investigate the effectiveness of osteopathic correction of hallux valgus of the Ist toe of the I–II degree.Materials and methods. The study involved 52 patients with valgus deformity of I toe, aged from 18 to 40 years. Two groups were formed by randomization envelopes method: the main group (26 participants who received osteopathic correction) and the control group (26 participants who received imitation of osteopathic correction). At the beginning and at the end of the study, the osteopathic status and severity of clinical manifestations of hallux valgus of the first finger were assessed (using the AOFAS questionnaire and the clinical-radiological Grulier scale, as well as radiography of the feet with a load in a direct projection).Results. Patients with valgus deformity of the Ist toe are characterized by the presence of global postural disorders, regional biomechanical disorders of the head, neck regions (structural and visceral component), lumbar and pelvic regions (structural and visceral component), as well as dura mater. Local somatic dysfunctions of the musculoskeletal system (tarsal-metatarsal and metatarsal-phalangeal joints, diaphragm, foot bones) and craniosacral system (temporomandibular joint, TMJ, skull sutures) were also revealed. Osteopathic correction is accompanied by a statistically significant (pConclusion. The results obtained during the study allow to consider the possibility of recommending the inclusion of osteopathic correction in the complex conservative treatment of hallux valgus of the Ist toe.

The aim of the study was to analyze differential gene expression in Burkholderia pseudomallei strains with different survival rates under cold stress conditions.Materials and methods. Three strains of B. pseudomallei (sequence types ST 46, ST 70, and ST 85) were used as model strains. The RNA was isolated using the membrane columns method and stabilized through dehydration. The cDNA was sequenced on the Illumina MiSeq platform. Gene functions were classified using the KEGG PATHWAY database.Results and discussion. Based on the analysis of transcriptomes of B. pseudomallei strains after prolonged exposure to cold stress, the molecular mechanisms of B. pseudomallei adaptation to low temperatures have been described for the first time ever. It was shown that adaptation of B. pseudomallei to cold stress is associated with regulatory processes leading to a significant decrease in the total transcriptional activity. Two strategies of adaptation to low temperatures have been found: 1) modulation of regulatory processes leading to suppression of gene expression of the main metabolic pathways to the minimum level that ensures cell viability and activation of the minimum required set of stress response genes, and 2) less noticeable suppression of general metabolism in combination with activation of expression of an extended range of genes for cold and heat shock, general, osmotic, and universal stresses. Both mechanisms provide the causative agent of melioidosis with survival under conditions of prolonged cold stress at low positive temperatures. The first strategy showed greater efficiency at negative temperatures. The transition of B. pseudomallei to a viable but uncultivated state occurs in the long term (at least 2 years). While with the second strategy, this happens within 2 months. Assessment of the potential and molecular mechanisms of adaptation of this bacterium to cold stress is necessary to understand the degree of risk in case of a possible introduction of B. pseudomallei into regions with a temperate climate and to develop effective measures to ensure the biosafety of the environment.

A universal approach to the construction of antibody–drug conjugates (ADCs) has been developed. It relies on periodate oxidation of naturally present glycans of immunoglobulin G, followed by oxime ligation and, optionally, copper(I)-catalyzed alkyne-azide cycloaddition for conjugation with a toxic payload. The introduction of highly absorbing cyanine dyes into the linker allows for facile determination of the drug–antibody ratio. We applied this methodology to the synthesis of cytotoxic conjugates of an antibody against the tumor-associated antigen PRAME with doxorubicin and monomethyl auristatin E (MMAE). The resultant conjugates retained their affinity to a large extent, yet their cytotoxicity in vitro varied dramatically: while the doxorubicin-based conjugate did not produce any effect on cells, the MMAE-based one demonstrated specific activity against PRAME-expressing cancer cell lines. Importantly, the latter conjugate constitutes the first reported example of a PRAME-targeting ADC.

Microwave circuit electrodynamics of disordered superconductors is a very active research topic spawning a wide range of experiments and applications. For compact superconducting circuit elements, the transition to an insulating state poses a limit to the maximum attainable kinetic inductance. It is therefore vital to study the fundamental noise properties of thin films close to this transition, particularly in situations where a good coherence and temporal stability is required. In this paper, we present measurements on superconducting granular aluminum microwave resonators with high normal state resistances, where the influence of the superconductor to insulator phase transition is visible. We trace fluctuations of the fundamental resonance frequency and observe, in addition to a 1/f noise pattern, a distinct excess noise, reminiscent of a random telegraph signal. The excess noise shows a strong dependency on the resistivity of the films as well as the sample temperature, but not on the applied microwave power., 6 pages, 4 figures

Superconducting microcircuits and metamaterials are promising candidates for use in new generation cryogenic electronics. Their functionality is largely justified by the macroscopic distribution of electromagnetic fields in arranged unit cells, rather than by the microscopic properties of composite materials. We present a new method for visualizing the spatial structure of penetrating microwaves with microscopic resolution in planar superconducting macroscopic resonators as the most important circuit-forming elements of modern microelectronics. This method uses a low-temperature laser scanning microscope that examines the phase (i.e., direction) and amplitude of local radio-frequency currents versus the two-dimensional coordinates of the superconducting resonant structure under test. Phase-sensitive contrast is achieved by synchronizing the intensity-modulated laser radiation with the resonant harmonics of the microwave signal passing through the sample. In this case, the laser-beam-induced loss in the illuminated area will strongly depend on the local phase difference between the RF carrier signal and the spatially temporal structure of the focused laser oscillation. This approach eliminates the hardware limitations of the existing technique of radio-frequency microscopy and brings the phase-sensitive demodulation mode to the level necessary for studying the physics of superconducting metamaterials. The advantage of the presented method over the previous method of RF laser scanning microscopy is demonstrated by the example of the formation of standing waves in a spiral superconducting Archimedean resonator up to the 38th eigenmode resonance., Comment: 10 pages, 8 figures

We investigate the formation of single and multiple optical bottle beams on the optical axis using a diffractive axicon with amplitude or phase apodization. The proposed approach allows one to control the location and the contrast of the boundaries of the generated dark intensity regions on the optical axis. Experimental results obtained using a spatial light modulator are in good agreement with numerically obtained ones. We successfully used the designed and experimentally formed set of three optical bottle beams for trapping light-absorbing agglomerations of carbon nanoparticles in air under the action of photophoretic forces. This confirms the efficiency of the proposed approach for optical manipulation applications.

Abstract Exchange-coupled spin valves based on ferromagnetic alloys CoFeNi and antiferromagnetic alloy FeMn are obtained on flexible polyimide substrates by magnetron sputtering. The magnetoresistive properties of films and microstrips of spin valves are measured at various degrees of bending deformation of the sample. The behavior of the dependence of the deformation sensitivity of the spin valve on the interaction between the magnetic layers and on the arrangement of the anisotropy axes with respect to the deformation vector is characterized. It is found that the deformation sensitivity decreases with an increase in the interval between the fields of magnetization reversal of the free and fixed layers in the spin valve.

Broad antiviral activity in vitro is known for many organic photosensitizers generating reactive oxygen species under irradiation with visible light. Low tissue penetration of visible light prevents further development of antiviral therapeutics based on these compounds. One possible solution to this problem is the development of photosensitizers with near-infrared absorption (NIR dyes). These compounds found diverse applications in the photodynamic therapy of tumors and bacterial infections, but they are scarcely mentioned as antivirals. In this account, we aimed to evaluate the therapeutic prospects of various NIR-absorbing and singlet oxygen-generating chromophores for the development of broad-spectrum photosensitizing antivirals.

Daily variations of integrated water vapor content in the atmosphere in the region of the Nizhnekamsk HPP were examined, from measurement data of GNSS radio signals in autumn 2010. It was established that the difference of these variations between the remote station and the stations at the buildings of the HPP were caused by evaporation from the surface of the water reservoir, and has an expressed daily variation with a maximum at 12:00 UTC and a range approximately the variation of 0.4 kg/m2.

The dependence of the Neel temperature on the thickness of the dysprosium layer has been studied. It is shown that the temperature range within which the paramagnetic–antiferromagnetic phase transition takes place depends on the microstructure and thickness of the dysprosium layer. Spin valves based on a CoFe alloy with dysprosium as an antiferromagnetic layer are manufactured via magnetron sputtering. It is shown that unidirectional anisotropy forms in the CoFe/Dy interface. The direction of the exchange bias field depends on the direction of the magnetic moment of the CoFe layer in the formation of exchange coupling.

Abstract The role of size effects in the formation of the magnetic structure of Dy and Ho thin films in absence of epitaxial strain is studied in this work. It was found that, for Dy in the temperature range between the Néel temperature and the Curie temperature of bulk Dy and, for Ho, in the temperature range between the Néel temperature and the temperature of phase transition into the conic phase, the temperature dependences of the period of magnetic helicoid in the bulk and film metals are similar. The character of the transition into the ferromagnetic phase in the Dy films changes at lower temperatures, and the transition into the commensurable conic phase in the Ho films is suppressed. This is explained exclusively by the influence of dimensional effects.

The influence of the state of interfaces on the magnetoresistive properties of Co/Cu superlattices has been studied by the methods of nuclear magnetic resonance (NMR) and X-ray reflectometry. It has been found that the magnetron-sputtered superlattices with the highest value of the giant magnetoresistance (GMR) effect have the largest fraction of highly perfect Co/Cu interlayer boundaries, as well as practically the smallest fraction of cobalt atoms localized in the interfaces.

Currently, due to the principle of adversarial proceedings, almost every expert's opinion is accompanied by its review by a specialist engaged by one or another party to the process. One of the shortcomings reflected in the reviews is a violation of the procedure for subscribing to the expert's warning of criminal liability for giving a deliberately false conclusion under article 307 of the Criminal code of the Russian Federation. Failure to comply with this very important procedure may result in the recognition of the expert's opinion as inadmissible evidence. In our opinion, the analysis of judicial practice and procedural rules governing this procedure, as well as the proposed recommendations, will help law enforcement entities in assessing the expert's opinion and its admissibility as evidence in the case.

Production of small discrete DNA nanostructures containing covalent junctions requires reliable methods for the synthesis and assembly of branched oligodeoxynucleotide (ODN) conjugates. This study reports an approach for self-assembly of hard-to-obtain primitive discrete DNA nanostructures-"nanoethylenes", dimers formed by double-stranded oligonucleotides using V-shaped furcate blocks. We scaled up the synthesis of V-shaped oligonucleotide conjugates using pentaerythritol-based diazide and alkyne-modified oligonucleotides using copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) and optimized the conditions for "nanoethylene" formation. Next, we designed nanoethylene-based "nanomonomers" containing pendant adapters. They demonstrated smooth and high-yield spontaneous conversion into the smallest cyclic product, DNA tetragon aka "nano-methylcyclobutane". Formation of DNA nanostructures was confirmed using native polyacrylamide gel electrophoresis (PAGE) and atomic force microscopy (AFM) and additionally studied by molecular modeling. The proposed facile approach to discrete DNA nanostructures using precise adapter-directed association expands the toolkit for the realm of DNA origami.

Spin valves with holmium layers and three-layer structures metal/Ho/metal were prepared by magnetron sputtering. A holmium layer in the spin valves is polycrystalline with weak axial texture. The structural coherence length along the hexagonal c-axis is approximately 2/5 of the total thickness of the holmium layer. Field dependences of the spin valves magnetoresistance were measured at different temperatures. Correlation was revealed between magnetic state in holmium layer and the shape of magnetoresistive curve. Deviation of magnetic moments of the reference layer and the adjacent part of holmium from the applied magnetic field was investigated. The field induced mobility of the magnetic helicoid in holmium layers was revealed.

Using high-vacuum magnetron sputtering, epitaxial Dy films were synthesized on Nb and Ta buffer layers on single-crystal Al2O3 substrates with different crystallographic orientations. It was established that the epitaxial relationships [11 $$\bar {2}$$ 0]Al2O3|| [011]Nb(Ta) and [1 $$\bar {1}$$ 02]Al2O3||[011]Nb(Ta) are satisfied with growing a Nb(Ta) buffer layer on single-crystal sapphire substrates with different crystallographic orientations. The second relationship has never been observed up to now; this may be because the growth rates upon magnetron sputtering are approximately two orders higher than those upon molecular-beam epitaxy. It was established that the Dy crystal lattice expansion in the basal plane by 2.8–3% occurs in all cases. Contrary to the samples grown on Nb, the Dy films grown on the Ta buffer layers are characterized by a larger value of the saturation magnetization, whereas its maximum value is attained in the polycrystalline Dy films.

The structure of a material promising for magnetic memory elements based on Fe/Pd/Gd/Pd superlattices has been investigated by X-ray analysis and electron microscopy. Microstructural transformations in the superlattices and the influence of microstructure modification on the magnetic properties of the system are determined. It is shown that intense diffusion of Pd atoms to Gd layers occurs in the superlattices under study. The presence of a paramagnetic Pd layer changes the character of exchange interaction between neighboring ferromagnetic layers due to the induced magnetic moment on Pd atoms near the interface because of the interface imperfection. Nanocrystalline inclusions are found in the Pd/Gd/Pd layers, which are suggested to affect the specificity of magnetic ordering in these systems, as confirmed by magnetic measurements.

A new method of phase recovery in neutron reflectometry is proposed based on the use of the Gd reference layer deposited on the top of an “unknown” layered structure. The idea of the method is to apply the energy dependence of neutron scattering length density to change the reference layer properties. Using three reflectivity curves at different neutron energies, the modulus and phase of the coefficient of reflection from the “unknown” structure can be reconstructed. We discuss the mathematics of phase recovery and present the first experimental results for a multilayered system.

A method of universal thermomagnetic treatment forming a pairwise opposite exchange bias in spin valves, which are sensor elements of a Wheatstone bridge, has been developed. The method is based on the formation of two magnetic phases in a spin valve upon the transition of a synthetic antiferromagnet into a spin-flop state. Thermomagnetic treatment in a two-phase state leads to the formation of a pairwise mutually opposite exchange bias in different elements of a Wheatstone bridge. The direction of a formed exchange bias is governed by the uniaxial anisotropy of every element.

Spin valves comprising a synthetic antiferromagnet and a CoFe/Dy/CoFe structure in the pinned layer were prepared by magnetron sputtering. It is shown that the Dy layer is characterized by crystallites, the [0002] direction of which is perpendicular to the film plane; a part of nanostructure, in which the spin-dependent electron scattering occurs, is characterized by smooth interfaces. Variations of magnetotransport properties of the spin valve, which are due to the formation of antiferromagnetic order in the dysprosium layer, are observed. Peculiarities of noncollinear magnetic order of the Dy layer were found to depend on the direction of magnetic moments of adjacent layers and magnetic field strength when passing through the Neel temperature.

The statistical method for describing the intermittency coefficient in the region of laminar–turbulent boundary layer transition at the low level of external perturbations is proposed. The method is based on the assumption that turbulence develops when the velocity deviates locally in space and time from the mean by a threshold value. The analytical formulas are obtained for the frequency of occurrence of the coherent structures (turbulent spots and wedges) and for the intermittency coefficient or the mean fraction of the surface area covered by them in the case of two basic scenarios of transition, namely, the enhancement of steady crossflow instability vortices on the swept wing and the Tollmien–Schlichting waves.

The microwave phenomena that occur in magnetic multilayer (CoFe)/Cu nanostructures, which have a giant magnetoresistance, are studied. The transmission of waves through a nanostructure is used to investigate the microwave giant magnetoresistance effect. The changes in the transmission coefficient at frequencies of 29–38 GHz are found to exceed the relative magnetoresistance, which distinguishes the system under study from the nanostructures studied earlier. Ferromagnetic and spin-wave resonances are used to study the angular dependences of the microwave absorption spectra of a multilayer (CoFe/Cu)n nanostructure. The following parameters are determined: the critical angle that determines the boundaries of the ranges of excitation of uniform and nonuniform spin modes, the type of boundary conditions describing the pinning of spins on the outer nanostructure surfaces, and the surface anisotropy and exchange interaction constants.

Annual measurements from two stations of the satellite monitoring system of the Sayano-Shushenskaya HPP are considered. This data was processed using the absolute PPP method and the relative method in the BERNESE software product. The RMS between the two solutions was 2.0 – 3.5 mm for the horizontal coordinates and 6.3 – 7.5 mm for the height. Using the PPP method, it was established that the annual variation of the earth’s crustal sediments in the area of the HPP due to the effect of atmospheric loads is 31.3 mm, and the annual variation due to the influence of the water reservoir is 9.7 mm. PPP technology can be used to monitor the horizontal position of hydropower structures on a compressible base. Using the PPP method, geodynamic studies of differences in the sediments of the earth’s crust caused by the water reservoir influence at the locations of base stations and monitoring stations can also be performed.

A new integrable system of equations that describes the effect of self-induced transparency for few-cycle terahertz pulses propagating in a system of resonant tunnel transitions is obtained. This system is derived within an approach based on the concept of envelopes for the electric field of a pulse and dipole moments of resonant and nonresonant transitions involved in the interaction with it. This approach makes it possible to describe solitons, whose velocity can be much less than the linear group velocity of light in the medium. This distinguishes it favorably from the method in which the concept of envelopes is not used but the density of the medium is assumed to be low.