342 research outputs found
X-ray line formation in the spectrum of SS 433
The mechanisms for the formation of X-ray lines in the spectrum of SS 433 are
investigated by taking into account the radiative transfer inside the jets. The
results of Monte Carlo numerical simulations are presented. The effect of a
decrease in line intensity due to scattering inside the jet turns out to be
pronounced, but it does not exceed 60% in magnitude on the entire grid of
parameters. The line broadening due to scattering, nutational motion, and the
contribution of satellites can lead to overestimates of the jet opening angle
from the line widths in Chandra X-ray observations. The fine structure
of the lines turns out to be very sensitive to the scattering effects. This
makes its investigation by planned X-ray observatories equipped with
high-resolution spectrometers (primarily Astro-H) a powerful tool for
diagnosing the parameters of the jets in SS 433.Comment: 23 pages, 14 figures, to be published in Astronomy Letters, v. 38, n.
7, p. 443 (2012
Neurotechnologies in Professional Education: Reflection of Their Possibilities
Цель статьи - проанализировать возможности применения нейротехнологий в профессиональном образовании, представить организационную форму их реализации в виде виртуальных мастерских.The purpose of the article is to analyze the possibilities of using neurotechnologies in vocational education, to present the virtual workshops as the organizational form of their implementation
Evaluation of the effect of the use of the drug ticagrelor in patients with acute coronary syndrome on achieving the target indicator “reduction of mortality from diseases of the circulatory system” in 2022-2024
Aim. To evaluate the effect of the use of the double antiplatelet therapy (DAT) with ticagrelor compared to DAT with clopidogrel and antithrombotic therapy with acetyl salicylic acid (ASA) in patients with acute coronary syndrome and patients with high coronary risk on the target indicator (CP) of the state program (GP) “Development of Healthcare” and the federal project “Fight against cardiovascular diseases” — reducing mortality from diseases of the circulatory system (BSC).Material and methods. All adult Russian patients with a diagnosis of ACS eligible for DAT were considered as the target population; in the second and third years, only patients with high coronary risk continued treatment. The calculation of the number of deaths that can be prevented using DAT ticagrelor 90 mg + ASA vs DAT of clopidogrel + ASA within 1st year from the date of diagnosis was based on the clinical efficacy data of the PLATO study. The number of deaths that can be prevented with the use of DAT ticagrelor 60 mg + ASA — instead of ASA monotherapy patients with a history of myocardial infarction was made based in the clinical efficacy results of the PEGASUS study. It was calculated what proportion of the target indicators could be achieved in 2022-24 years by using DAT with ticagrelor instead of clopidogrel or ASA monotherapy.Results. The use of DAT with ticagrelor vs DAT with clopidogrel or ASA for the treatment of patients with ACS will prevent additional 5389, 5704 and 6012 deaths in 2022-2024, that will ensure the implementation of the CP “reduction of mortality from BSC” GP “Development of healthcare” in the Russian Federation by 36,9%, 26,0% and 20,6% respectively.Conclusion. The use of DAT with ticagrelor for the treatment of patients with acute coronary syndrome ensure the implementation of the CP “reduction of mortality from BSC” GP “Development of healthcare” in the Russian Federation in 2024 by 20,6%
Upper limits on the isotropic diffuse flux of cosmic PeV photons from Carpet-2 observations
Isotropic diffuse gamma-ray flux in the PeV energy band is an important tool
for multimessenger tests of models of the origin of high-energy astrophysical
neutrinos and for new-physics searches. So far, this flux has not yet been
observed. Carpet-2 is an air-shower experiment capable of detecting
astrophysical gamma rays with energies above 0.1 PeV. Here we report the upper
limits on the isotropic gamma-ray flux from Carpet-2 data obtained in 1999-2011
and 2018-2022. These results, obtained with the new statistical method based on
the shape of the muon-number distribution, summarize Carpet-2 observations as
the upgraded installation, Carpet-3, starts its operation.Comment: 5 pages, 3 figures, JETPL.cls; V2: references added, version accepted
by JETP Letter
Magnetic Field Amplification in Galaxy Clusters and its Simulation
We review the present theoretical and numerical understanding of magnetic
field amplification in cosmic large-scale structure, on length scales of galaxy
clusters and beyond. Structure formation drives compression and turbulence,
which amplify tiny magnetic seed fields to the microGauss values that are
observed in the intracluster medium. This process is intimately connected to
the properties of turbulence and the microphysics of the intra-cluster medium.
Additional roles are played by merger induced shocks that sweep through the
intra-cluster medium and motions induced by sloshing cool cores. The accurate
simulation of magnetic field amplification in clusters still poses a serious
challenge for simulations of cosmological structure formation. We review the
current literature on cosmological simulations that include magnetic fields and
outline theoretical as well as numerical challenges.Comment: 60 pages, 19 Figure
Comparative Dissolution Kinetics of Several Multisource Thioctic Acid Products
The relationship between dissolution and bioavailability is an example of the interdependency between the quality of a medicinal product and its safety and efficacy. The uniqueness of thioctic acid is that it can exist in an oxidised and a reduced form, showing lipophilic (lipoic acid) and hydrophilic (dihydrolipoic acid) properties. Bioavailability studies of thioctic acid are necessary to evaluate the expected therapeutic effect and mitigate side effects of the medicinal product.The aim of the study was to carry out equivalence dissolution testing to compare the release of thioctic acid from medicinal products produced by several manufacturers.Materials and methods: the study used a reference medicinal product and three multisource medicinal products by different manufacturers; more specifically, film-coated tablets containing 600 mg of thioctic acid. The experiment was carried out in dissolution media at pH of 6.8±0.05 and 1.2±0.05. Statistical analysis was performed by calculating the average amounts of the substance dissolved, the standard deviation (SD), and the relative standard deviation (RSD, %) using Microsoft Office Excel 2007.Results: The authors chose the testing conditions (dissolution media pH values of 6.8±0.05 and 1.2±0.05) taking into account the nature and characteristics of thioctic acid. The comparison of thioctic acid release profiles based on the calculation of the similarity factor (f2) showed that the dissolution profiles of multisource medicinal products 2 and 3 at pH 6.8 were equivalent to that of the reference medicinal product (more than 85% of the active pharmaceutical ingredient released within 15 minutes) and the dissolution profile of multisource medicinal product 1 was not equivalent to it (with f2 of 28).Conclusions: the established differences in the rate and degree of active ingredient release from the studied medicinal products may indicate possible differences in their pharmacological effectiveness in vivo
Laboratory evidence of dynamo amplification of magnetic fields in a turbulent plasma
Magnetic fields are ubiquitous in the Universe. The energy density of these fields is typically comparable to the energy density of the fluid motions of the plasma in which they are embedded, making magnetic fields essential players in the dynamics of the luminous matter. The standard theoretical model for the origin of these strong magnetic fields is through the amplification of tiny seed fields via turbulent dynamo to the level consistent with current observations. However, experimental demonstration of the turbulent dynamo mechanism has remained elusive, since it requires plasma conditions that are extremely hard to re-create in terrestrial laboratories. Here we demonstrate, using laser-produced colliding plasma flows, that turbulence is indeed capable of rapidly amplifying seed fields to near equipartition with the turbulent fluid motions. These results support the notion that turbulent dynamo is a viable mechanism responsible for the observed present-day magnetization
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