•Glass-coated amorphous microwires with composition Co69Fe4Cr4Si12B11 under heat treatment.•Changes of microstructure, phase composition and fracture morphology during crystallization.•Changes of ...circumferential diagonal GMI ratio with the nucleation of Co nanocrystals and phase transformations.•Microstructure formation in amorphous phase during crystallization.•Crystallization process at the second stage with formation of metastable phase Me23B6.
Amorphous Co69Fe4Cr4Si12B11 glass-coated microwires after heat treatment in the temperature range of 250–600 °C during 30 min were investigated. Changes of microstructure, phase composition, fracture morphology, and giant magnetoimpedance (GMI) properties were shown. It is confirmed that a significant increase in the GMI effect was possible not only due to the structural relaxation, but also as a result of phase transformations at the temperature close to the onset of crystallization. It is shown that at the very initial stage of the nucleation of Co nanocrystals, a sharp increase in circumferential diagonal GMI component was observed, a further increase in the amount of the crystalline Co phase was accompanied by degradation of this effect. The most significant GMI ratio was obtained for microwires annealed at 430 °C. At 450 °C and above, an irreversible decrease of the GMI ratio took place. It was caused by the formation of Co crystals, decrease in amount and composition change of the amorphous phase during primary and secondary crystallization. At the final stage of the Co crystals segregation the secondary crystallization of the residual amorphous phase occurred with formation of a metastable τ-phase with a Me23B6 type structure. Thermal stability of the τ-phase was analyzed.
The work is a review of neutronographic investigations of supramolecular structures on upgraded small-angle spectrometer YuMO. Here, key parameters of small-angle spectrometers are considered. It is ...shown that two-detector system is the basis of YuMO upgrade. It allows to widen the dynamic q-range twice. In result, the available q-range is widened and dynamic q-range and data collection rate are doubled. The detailed description of YuMO spectrometer is given.The short review of experimental researches made on the spectrometer in the polymers field, biology, material science and physical chemistry is given. The current investigations also have a methodological aspect. It is shown that upgraded spectrometer provides advanced world level of research of supramolecular structures.
Base excision repair (BER) is aimed at repair of damaged bases, which are the largest group of DNA lesions. The main steps of BER are recognition and removal of the aberrant base, cutting of the DNA ...sugar-phosphate backbone, gap processing (including dNMP insertion), and DNA ligation. The precise function of BER depends on the regulation of each step by regulatory/accessory proteins, the most important of which is poly(ADP-ribose) (PAR) polymerase 1 (PARP1). PARP1 plays an important role in DNA repair, maintenance of genome integrity, and regulation of mRNA stability and decay. PARP1 can therefore affect BER both at the level of BER proteins and at the level of their mRNAs. There is no systematic data on how the PARP1 content affects the activities of key BER proteins and the levels of their mRNAs in human cells. Whole-cell extracts and RNA preparations obtained from the parental HEK293T cell line and its derivative HEK293T/P1-KD cell line with reduced PARP1 expression (shPARP1-expressing cells, a PARP1 knockdown) were used to assess the levels of mRNAs coding for BER proteins: PARP1, PARP2, uracil DNA glycosylase (UNG2), AP endonuclease 1 (APE1), DNA polymerase β (POLβ), DNA ligase III (LIG3), and XRCC1. Catalytic activities of the enzymes were evaluated in parallel. No significant effect of the PARP1 content was observed for the mRNA levels of UNG2, APE1, POLβ, LIG3, and XRCC1. The amount of the PARP2 mRNA proved to be reduced two times in HEK293T/P1-KD cells. Activities of these enzymes in whole-cell extracts did not differ significantly between HEK293T and HEK293T/P1-KD cells. No significant change was observed in the efficiencies of the reactions catalyzed by UNG2, APE1, POLβ, and LIG3 in conditions of PAR synthesis. A DNA PARylation pattern did not dramatically change in a HEK293T/P1-KD cell extract with a reduced PARP1 content as compared with an extract of the parental HEK293T cell line.
Abstract
The morphometric characteristics and bottom topography of typical shallows behind the island are characterized. The long – term and seasonal dynamics of the water level in the Rybinsk ...reservoir during the period from 1947 to 2020 is considered. The periods of fluctuations of the main hydrometeorological parameters in relation to the investigated section of the reservoir are shown. Based on archival and modern observation data on the structure of currents, the patterns of water transport and water exchange in the shallows are investigated, taking its seasonal overgrowth with macrophytes into account.
Base excision repair (BER) is aimed at repair of damaged bases, which are the largest group of DNA lesions. The main steps of BER are recognition and removal of the aberrant base, cutting of the DNA ...sugar-phosphate backbone, gap processing (including dNMP insertion), and DNA ligation. The precise function of BER depends on the regulation of each step by regulatory/accessory proteins, the most important of which is poly(ADP-ribose) (PAR) polymerase 1 (PARP1). PARP1 plays an important role in DNA repair, maintenance of genome integrity, and regulation of mRNA stability and decay. PARP1 can therefore affect BER both at the level of BER proteins and at the level of their mRNAs. There is no systematic data on how the PARP1 content affects the activities of key BER proteins and the levels of their mRNAs in human cells. Whole-cell extracts and RNA preparations obtained from the parental HEK293T cell line and its derivative HEK293T/P1-KD cell line with reduced PARP1 expression (shPARP1-expressing cells, a PARP1 knockdown) were used to assess the levels of mRNAs coding for BER proteins: PARP1, PARP2, uracil DNA glycosylase (UNG2), AP endonuclease 1 (APE1), DNA polymerase β (POLβ), DNA ligase III (LIG3), and XRCC1. Catalytic activities of the enzymes were evaluated in parallel. No significant effect of the PARP1 content was observed for the mRNA levels of UNG2, APE1, POLβ, LIG3, and XRCC1. The amount of the PARP2 mRNA proved to be reduced two times in HEK293T/P1-KD cells. Activities of these enzymes in whole-cell extracts did not differ significantly between HEK293T and HEK293T/P1-KD cells. No significant change was observed in the efficiencies of the reactions catalyzed by UNG2, APE1, POLβ, and LIG3 in conditions of PAR synthesis. A DNA PARylation pattern did not dramatically change in a HEK293T/P1-KD cell extract with a reduced PARP1 content as compared with an extract of the parental HEK293T cell line.
We study the influence of the Kondo effect on the spin relaxation in systems with anisotropic Kondo interaction at temperatures both high and low as compared with the static magnetic field. In the ...absence of the Kondo effect, the electron spin resonance linewidth is not narrowed in the whole temperature range due to the high anisotropy of the Kondo interaction. The Kondo effect leads to the universal energy scale, which regulates the temperature and magnetic field dependence of different kinetic coefficients and results in a mutual cancelation of their singular parts in a collective spin mode.
The possibility of appearance of inhomogeneous superconducting Fulde—Ferrell—Larkin—Ovchinnikov (FFLO) states in magnetic superconductors in a cryptoferromagnetic phase with helical magnetic ordering ...has been analyzed. The dependence of the critical temperature on the angle between the wave vectors of the spatial modulation of the FFLO state and helical magnetic structure has been calculated within the proposed model. It has been shown that their mutually perpendicular orientation corresponds to the most energetically favorable state. The numerical calculations have also shown the existence of a tricritical point on a line separating the Bardeen—Cooper—Schrieffer and FFLO phases on the phase diagram of states. Furthermore, FFLO states can appear in a magnetic superconductor even at fairly strong exchange fields because of the difference between the effective masses of conduction electrons in different spin subbands and the anisotropy of the Fermi surface.
Using a multidetector system on the YuMO spectrometer allows shortening the time of measurements. The quantitative comparison of the measurement time using one and two-detector mode is done. The time ...range for experiments was from several minutes up to 12 hours. It was shown that two-detector system shortens more than twice the time of the measurement. While making a structural investigation using advanced software the two-detector system allows to treat the data at a qualitatively new level. An example illustrating the features of the channels choice and measurement time on the spectrometer was shown. The results of this paper could be used when planning the experiments on the YuMO spectrometer, for modernization of the installation and for equipment using time-of-flight method.
Algorithms are realized for localizing vibration activity sources in complex mechanoacoustic systems using finite element modeling. For the case of one source, the localization method was used in the ...least squares form applied to the first eigenvector of the sample correlation matrix. It is shown that frequency summation can significantly increase the localization accuracy in this case. Considerable attention is paid to assessing the number of simultaneously operating vibration sources and the possibility of correctly localizing them. The efficiency of two source localization methods was compared: the maximum likelihood method calculated for a single source and the MUSIC (Multiple Signal Classification) method specially modified for this problem. It is shown that the modified MUSIC method is more efficient in solving the localization problem with two sources compared to the maximum likelihood method calculated for a single source. It is noted that the maximum likelihood method calculated for two or more sources cannot be applied because of the too high computational complexity.
Changes in the higher aquatic vegetation (HAV) of the protected shallow water “Krasnyi Ruchei” from 1989 to 2019 have been analyzed based on aerial imageries, multidate satellite images, and direct ...field studies. Images from the second half of July to late September are used to study of the overgrowing. An inverse relationship has been found between the degree of overgrowing and water level. The degree of overgrowing of the shallow water is highest (82–86%) at low values of the water level (99.6–99.7 m) and slightly lower (63–78.8%) at higher values (100.3–100.7 m). This is inconsistent with the data on the Rybinsk Reservoir published before 2013; therefore, further research based on a more representative material is required. The specificity of the regulation of the Rybinsk Reservoir water level, as well as the predominant shallow water phase during the freeze-up period and throughout most of the vegetation season and high sedimentation rates, create favorable conditions for the distribution of HAV. By 2019, HAV in the shallow water had spread to a depth of 1.8 m and the area of overgrowing reached 73% of the normal water level. Helophytes occupied about 70% of the optimal shallow water area, while hydrophytes only 20%. Taking into account the high rate of sedimentation and shallowing, the rates of overgrowing of the studied shallow water will be more rapid in the nearest future, which can be controlled by maintaining a water level close to the normal water-surface elevation level of 101.81 m.
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