A system of four magnets which is a part of the SPASCHARM experimental setup at the U-70 accelerator facility for the study of spin effects in hadronic interactions is described. An unique magnet ...with the field of 2.4 T and a field uniformity at the level of 10
–4
in a working volume of 60 cm
3
is used to pump up and hold polarization in a polarized proton frozen target. A special wide-aperture magnet is the central part of the spectrometer of the setup based on the drift tubes. For precision steering the beam to the center of the target, two small magnets correctors developed by the Efremov Research Institute of Electrophysical Equipment have been manufactured and introduced into the setup.
The main goal of the SPASCHARM experiment is the systematic study of spin phenomena at intermediate energies. For this purpose, it is planned to create a beam of polarized protons and antiprotons. ...The research includes, among other things, the study of elastic scattering. Some of the required equipment for polarimetry is planned to be also used to study elastic scattering immediately after the creation of such a channel. In this work, a set of observables necessary for model-free reconstruction of elastic proton–proton scattering amplitudes is investigated and determined.
•Eight novel phages infecting hypermucoviscous K. pneumoniae of K1, K2, and K57 types were characterized at the genome level.•The bacteriophages were classified within the genus Kp32virus and ...Kp34virus.•Polysaccharide depolymerase genes of the phages were identified.•Depolymerases of K1 and K2 specific phages were recombinantly produced and characterized.
Hypermucoviscous (HV) strains of capsular types K1, K2 and K57 are the most virulent representatives of the Klebsiella pneumoniae species. Eight novel bacteriophages lytic for HV K. pneumoniae were isolated and characterized. Three bacteriophages, KpV41, KpV475, and KpV71 were found to have a lytic activity against mainly K. pneumoniae of capsular type K1. Two phages, KpV74, and KpV763 were lytic for K2 capsular type K. pneumoniae, and the phage KpV767 was specific to K57-type K. pneumoniae only. Two more phages, KpV766, and KpV48 had no capsular specificity. The phage genomes consist of a linear double-stranded DNA of 40,395–44,623bp including direct terminal repeats of 180–246 bp. The G + C contents are 52.3–54.2 % that is slightly lower than that of genomes of K. pneumoniae strains being used for phage propagation. According to the genome structures, sequence similarity and phylogenetic data, the phages are classified within the genus Kp32virus and Kp34virus of subfamily Autographivirinae, family Podoviridae. In the phage genomes, genes encoding proteins with putative motifs of polysaccharide depolymerase were identified. Depolymerase genes of phages KpV71 and KpV74 lytic for hypermucoviscous K. pneumoniae of K1 and K2 capsular type, respectively, were cloned and expressed in Escherichia coli, and the recombinant gene products were purified. The specificity and polysaccharide-degrading activity of the recombinant depolymerases were demonstrated.
The dependence of the conductivity and electric modulus of silver/polyacrylonitrile nanocomposites on the frequency of an alternating electric field has been studied at different temperatures and ...starting mixture AgNO3 contents. The frequency dependences on the conductivity of the nanocomposites in the range of 103–106 Hz are in good agreement with the power law f0.8. The observed relaxation maxima in the relation of the imaginary part of the electric modulus on the frequency can be explained by interfacial polarization. It was shown that the frequency dispersions of conductivity and electric modulus were well described by the Dyre and Cole-Davidson models, respectively. Using these models, we have estimated the relaxation times and the activation energies of these structures. A mechanism of charge transport responsible for the conductivity of nanocomposites is proposed. An assumption is made regarding the presence of Ag42+ and Ag82+ silver clusters in the polymer.
Optical microscopy has undergone significant changes in recent decades due to the improved diffraction limit of optical resolution and the development of high-resolution imaging techniques referred ...to under the common name fluorescence nanoscopy. These techniques allow researchers to observe in detail biological structures and processes at a nanoscale level to reveal previously hidden features and answer basic biological questions. The advanced methods of fluorescent nanoscopy include STED (Stimulated Emission Depletion) Microscopy, STORM (STochastic Optical Reconstruction Microscopy), PALM (Photo-activated Localization Microscopy), TIRF (Total Internal Reflection Fluorescence) microscopy, SIM (Structured Illumination Microscopy), MINFLUX (Minimal Photon Fluxes) microscopy, PAINT (Points Accumulation for Imaging in Nanoscale Topography), and RESOLFT (REversible Saturable Optical Fluorescence Transitions) microscopy, and others. Most these methods make it possible to obtain 3D images of the objects under study. In this review, we consider the principles of these methods, their advantages and disadvantages, and their application in biological research.
Nonlinear optical properties (nonlinear refraction index and two-photon absorption coefficient) of chalcoiodide glasses of the GexS90−xI10 system obtained by fusing germanium, germanium iodide and ...sulfur in an evacuated quartz ampoule were studied as a function of their macrocomposition. The dependence of nonlinear properties proved to be nonmonotonic. For stoichiometric ratio of the number of Ge and S atoms, the nonlinear refraction index reaches its minimum value and the two-photon absorption coefficient is maximal.
•Structure of glasses in the system GexS100−xI was studied using Raman spectroscopy.•The two-photon absorption in GexS100−xI glasses has a maximum for x≈33 at 800nm.•The nonlinear index in GexS100−xI glasses has a minimum for x≈33 at 800nm.•The nonlinear figure of merit for GexS100−xI glasses has a wide tuning range.
By sequencing 523 ancient humans, we show that the primary source of ancestry in modern South Asians is a prehistoric genetic gradient between people related to early hunter-gatherers of Iran and ...Southeast Asia. After the Indus Valley Civilization's decline, its people mixed with individuals in the southeast to form one of the two main ancestral populations of South Asia, whose direct descendants live in southern India. Simultaneously, they mixed with descendants of Steppe pastoralists who, starting around 4000 years ago, spread via Central Asia to form the other main ancestral population. The Steppe ancestry in South Asia has the same profile as that in Bronze Age Eastern Europe, tracking a movement of people that affected both regions and that likely spread the distinctive features shared between Indo-Iranian and Balto-Slavic languages.
Aim
During early post‐natal development, arterial contraction depends less on Ca2+‐signalling pathways but more on changes in Ca2+‐sensitivity compared to adult animals. Whether this difference is ...related to Rho‐kinase, one of the major players affecting Ca2+‐sensitivity, is unknown for intact vessels. Thus, we tested the hypothesis that Rho‐kinase critically contributes to the higher Ca2+‐sensitivity of contraction in intact arteries of 1‐week‐old rats.
Methods
We studied 1‐week‐old, 4‐ to 5‐week‐old and 10‐ to 12‐week‐old rats performing isometric myography, Ca2+‐fluorimetry and Western blotting using intact saphenous arteries and arterial pressure measurements under urethane anaesthesia.
Results
In 10‐ to 12‐week‐old rats, methoxamine (MX) produced vasoconstriction associated with an increase in Ca2+i and Ca2+‐sensitivity. In contrast, in 1‐week‐old rats these contractions were accompanied only by an increase in Ca2+‐sensitivity. All MX‐induced effects were reduced by the Rho‐kinase inhibitor Y‐27632; this reduction was complete only in 1‐week‐old rats. The Rho‐kinase specific site Thr855 on MYPT1 was increasingly phosphorylated by MX in vessels of 1‐week‐old, but not 10‐ to 12‐week‐old rats; this effect was also inhibited completely by Y‐27632. The Rho‐kinase inhibitor fasudil in a dose not affecting the pressor response to MX in 4‐ to 5‐week‐old rats reduced it considerably in 1‐week‐old rats.
Conclusion
Our results suggest that the higher Ca2+‐sensitivity of arterial contraction in 1‐week‐old compared to 10‐ to 12‐week‐old rats is due to a greater Rho‐kinase activity. Constitutively active Rho‐kinase contributes to MX‐induced contraction in 10‐ to 12‐week‐old rats. In 1‐week‐old rats, additional Rho‐kinase activation is involved. This remodelling of the Rho‐kinase pathway is associated with its increased contribution to adrenergic arterial pressure responses.
—We have studied structure formation of cement stone with the use of silica-containing and inert additives and mechanochemical activation. Rational compositions and the particle size composition of ...composite binders have been determined by X-ray diffraction, differential thermal analysis, and microstructural analysis, which makes it possible to obtain preset physicomechanical characteristics of cement stone and related concrete. The synergistic effect of pozzolanic and inert additives has been shown to activate hydration processes, densifying the microstructure of newly formed phases.
The danger of the wastes from the reprocessing of spent nuclear fuel is largely determined by the presence in them of long-lived actinides, first of all, americium and curium. The solution to the ...problem could be to involve together with plutonium its attendant actinides in the fuel cycle of fast reactors. This article considers the technologies (reactor, fuel fabrication, and spent fuel reprocessing) that are necessary for burning actinides as part of mixed uranium-plutonium nitride fuel. It is shown that the concentration of actinides, produced in a fast reactor, in the fuel will not exceed 0.5% h.a. For the transmutation of actinides separated from VVER spent fuel simultaneously with plutonium, it is expedient to increase the americium proportion in the fuel to 1.2%. Consideration is given to the possibility of using carbothermal synthesis of the initial powders and tablet technology for the manufacture of mixed uranium-plutonium nitride fuel, as well as the combined technology of spent-fuel reprocessing, planned for realization at a pilot-demonstration power complex with the BREST-300 reactor, and their suitability for involving neptunium and americium in the fuel cycle along with plutonium and uranium.
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