Summary
As a result of the conducted experimental studies on intranasal challenge of ICR mice, rabbits and miniature pigs (even in the maximum variant) with the doses of 4.0–5.5 lg PFU of monkeypox ...virus (MPXV), some clinical signs such as purulent conjunctivitis, blepharitis and ruffled fur were found only in mice. The 50% infective dose (CID50) of MPXV for these animals estimated by the presence of external clinical signs was 4.8 lg PFU, and LID50 estimated by the virus presence in the lungs of mice 7 days post‐infection taking into account its 10% application in the animal respiratory tract was 1.4 lg PFU. When studying the dynamics of MPXV propagation in mice challenged intranasally with 25 LID50 of MPXV, the maximum pathogen accumulation was revealed in nasal cavity, lungs and brain: 5.7 ± 0.1, 5.5 ± 0.1 and 5.3 ± 0.3 lg PFU/ml, respectively. The pathomorphological examination of these animals revealed the presence and replication of the pathogen in the traditional primary target cells for MPXV (mononuclear phagocyte system cells and respiratory tract epitheliocytes) as well as in some other types of cells (endothelial cells, reticular cells, connective tissue cells). Our use of these animals to assess the antiviral efficacy of some drugs demonstrated the agreement of the results (a significant positive effect of NIOCH‐14 and ST‐246) with those described in scientific literature, which opens up the prospects of using ICR mice as animal models for monkeypox to develop preventive antismallpox drugs.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
We present the final results from a high sampling rate, multi-month, spectrophotometric reverberation mapping campaign undertaken to obtain either new or improved H{beta} reverberation lag ...measurements for several relatively low-luminosity active galactic nuclei (AGNs). We have reliably measured the time delay between variations in the continuum and H{beta} emission line in six local Seyfert 1 galaxies. These measurements are used to calculate the mass of the supermassive black hole at the center of each of these AGNs. We place our results in context to the most current calibration of the broad-line region (BLR) R{sub BLR}-L relationship, where our results remove outliers and reduce the scatter at the low-luminosity end of this relationship. We also present velocity-resolved H{beta} time-delay measurements for our complete sample, though the clearest velocity-resolved kinematic signatures have already been published.
We present the first results from a high sampling rate, multimonth reverberation mapping campaign undertaken primarily at MDM Observatory with supporting observations from telescopes around the ...world. The primary goal of this campaign was to obtain either new or improved H Delta *b reverberation lag measurements for several relatively low luminosity active galactic nuclei (AGNs). We feature results for NGC 4051 here because, until now, this object has been a significant outlier from AGN scaling relationships, e.g., it was previously a ~2-3 Delta *s outlier on the relationship between the broad-line region (BLR) radius and the optical continuum luminosity-the R BLR-L relationship. Our new measurements of the lag time between variations in the continuum and H Delta *b emission line made from spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R BLR = 1.87+0.54 -0.50 light days and black hole mass of M BH = (1.73+0.55 -0.52) X 106 M. This radius is consistent with that expected from the R BLR-L relationship, based on the present luminosity of NGC 4051 and the most current calibration of the relation by Bentz et al.. We also present a preliminary look at velocity-resolved H Delta *b light curves and time delay measurements, although we are unable to reconstruct an unambiguous velocity-resolved reverberation signal.
Summary
This study presents results of the study of infectivity of avian influenza virus (AIV) A subtype H5N1 strains isolated from agricultural birds across the territory of the Russian Federation ...and CIS countries. The results of the susceptibility of chickens to the AIV isolates delivered by the aerosol route and the dissemination of the virus in the organs of infected birds are presented. As was observed, the sensitivity of birds to AIV by the aerosol route of infection is 30 times higher than by intranasal route, 500 times higher than by the oral route and 10 000 times higher than by the intragastric route of infection, which is indicative of higher permissivity of respiratory organs to AIV. The highest titres of AIV A subtype H5N1(A/Chicken/Kurgan/05/2005 strain) in aerosol‐infected chickens were found in nasal cavity mucosa, lungs, cloaca, serum and kidney, where viable virus accumulation was detected by 18 h post‐infection (p.i.). The highest virus titres were observed 54 h p.i. in lungs, serum and kidney, reaching the value of 8.16 lg EID50/g(ml) in the lungs. The results showed that birds infected by the aerosol route developed higher titres of virus than those infected by other routes.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
The catalyst active sites produce PP, whose properties - melt flow index (MFI) and molecular-weight distribution (as Mw/Mn) - depend on internal donors (ID) in the same manner for both methods of ...catalyst synthesis. Hence, the effect of ID on the catalyst active sites is not related with the effect of ID on the formation of MgCl2 crystallites with different cuts.
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•Polypropylene (PP) catalysts are prepared by two methods introducing internal donors (ID) during or after MgCl2 formation.•PP properties (melt index, Mw/Mn) depend on ID but the same manner for both methods of catalyst synthesis.•The effect of ID on the active sites is not related with the effect of ID on the formation of MgCl2 crystallite cuts.
Propylene polymerization catalysts with different internal donors (ID) are synthesized by two methods: (1) a standard method with ID introduction during formation of MgCl2 by reacting Mg(OEt)2 with TiCl4, and (2) the introduction of ID on MgCl2 already formed in the presence of butyl acetate (the substitution method). 1,3-diether, dibutyl phthalate (DBP) and pentane-2,4-diol-dibenzoate (PDDB) are used as ID. Catalysts prepared with the same ID by both methods slightly differ in their composition, activity and stereospecificity (the content of xylene soluble polypropylene (PP) fraction). But the catalyst active sites produce PP, whose properties (melt flow index, MFI, and molecular-weight distribution as Mw/Mn) depend on ID in the same manner for both methods of catalyst synthesis. Hence, the effect of ID on the catalyst active sites is not related with the effect of ID on the formation of MgCl2 crystallites with different cuts.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
An asymptotic solution of the Cauchy problem for a multidimensional wave equation with a localized initial function is constructed taking into account small dispersion effects. The three-dimensional ...case and the construction of the asymptotics for it are considered separately. With a special choice of the initial function in the three-dimensional case, the asymptotics is presented explicitly using the Airy and Scorer functions. As an example where dispersion effects arise, we consider the homogenization of a wave equation with a rapidly oscillating coefficient and construct an asymptotic solution of such an equation.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The first experiments on the observation of short pulsed superradiant (SR) emission with the excitation of a surface wave by a relativistic electron bunch moving in an oversized corrugated waveguide ...were performed. Subterahertz SR pulses with a central frequency of 0.14 THz, an ultrashort duration of 150 ps, and an extremely high peak power of 50-70 MW were generated. The experiments were based on a theoretical consideration including the quasioptical approach and direct particle-in-cell simulations.
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•Mycobacterial P450 is involved in metabolism of 7-dehydrocholesterol and vitamin D3.•Metabolism of sterols represent an adaptation mechanism for mycobacteria against human immune ...system.
Problems arising during treatment of tuberculosis are well known, therefore studies of Mycobacterium drug molecular targets are an area of particular importance. Members of the cytochrome P450 family (CYP) may belong to potential candidates for drug targets being involved in metabolism of biologically important molecules in the host organism. CYP124 of Mycobacterium tuberculosis (MTCYP124) catalyzes ω-hydroxylation of methyl-branched lipids. The data obtained in the present study indicate that this enzyme can also oxidize provitamin D3 (7-dehydrocholesterol) and vitamin D3. We found that the final product is different from 1α- and 25-hydroxyvitamin D3, so we propose that MTCYP124 is involved in alternative pathway for metabolism of vitamin D3.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
We consider the eigenproblem for the Laplacian inside a three-dimensional domain of revolution diffeomorphic to a solid torus, and construct asymptotic eigenvalues and eigenfunctions (quasimodes) of ...the whispering gallery-type. The whispering gallery-type asymptotics are localized near the boundary of the domain, and an explicit analytic representation in terms of Airy functions is constructed for such asymptotics. There are several different scales in the problem, which makes it possible to apply the procedure of adiabatic approximation in the form of operator separation of variables to reduce the initial problem to one-dimensional problems up to a small correction. We also discuss the relationship between the constructed whispering gallery-type asymptotics and classical billiards in the corresponding domain, in particular, such asymptotics correspond to almost integrable billiards with proper degeneracy. We illustrate the results in the case when a domain of revolution is obtained by the rotation of a triangle with rounded wedges.
DOI
10.1134/S1061920823040131
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Within the framework of the average approach and direct 3D PIC (particle-in-cell) simulations, we demonstrate that the gyrotrons operating in the regime of developed turbulence can sporadically emit ..."giant" spikes with intensities a factor of 100-150 greater than the average radiation power and a factor of 6-9 exceeding the power of the driving electron beams. Together with the statistical features such as a long-tail probability distribution, this allows the interpretation of generated spikes as microwave rogue waves. The mechanism of spikes formation is related to the simultaneous cyclotron interaction of a gyrating electron beam with forward and backward waves near the waveguide cutoff frequency as well as with the longitudinal deceleration of electrons.
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