Underground cosmic-ray experiments, including very large volume neutrino telescopes, depend on a precise description of the interaction cross sections of muons, which can travel large distances ...before reaching the detector. High-energy muons lose their energy almost exclusively via four processes: ionization, electron-positron pair production, bremsstrahlung and inelastic interaction with nuclei. At low energies, ionization is the dominant process, while above energies of about a TeV, the three other processes dominate the energy loss. We discuss the uncertainties of the cross sections of the energy loss processes used in the simulation chain of current very large volume neutrino telescopes and review recent theoretical improvements.
New method of investigation of atmospheric fronts by means of cosmic ray muon flux is considered. The method is based on searches of changes in the muon flux in the atmosphere, caused by waves from ...atmospheric fronts. For search of such waves 105 atmospheric fronts passing over Moscow were analyzed. The method allows determining the directions of the waves and their periods.
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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
A new approach to analyzing the intensity of the muon flux from different azimuthal directions is proposed that allows the detection of waves from large-scale atmospheric phenomena (fronts, ...thunderstorm cells) in the atmosphere.
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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
New method of EAS investigations by local muon density spectra and results of muon bundles detection in NEVOD–DECOR experiment are considered. The observed excess of muon bundles from very high ...energy cosmic rays and results of some other experiments which are evident for an additional flux of very high energy muons are analyzed. A possibility of their explanation through quark–gluon plasma blob production and its consecutive decay is discussed. The ways of experimental checks of this model are considered.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Four most widely used models of hadronic interactions at high energies implemented in CORSIKA program were compared basing on the simulation of the first nucleus–nucleus interactions of cosmic rays ...with the atmosphere. For this comparison the distributions of the number of produced particles of different types were obtained, as long as the mean values of these numbers. The dependences of the fraction of the collision energy carried by different secondary particles on the mass of the primary particle were calculated for each model. The check of the electric charge conservation law implementation was performed. Comparison shows vast differences between the models in some cases that may result in different interpretation of experimental data.
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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
Background: Over the last few decades of treatment, the outcomes for at least some subsets of neuroendocrine neoplasms (NENs) have improved. However, the identification of new vulnerabilities for ...this heterogeneous group of cancers remains a priority. Methods: Using two libraries of compounds selected for potential repurposing, we identified the inhibitors of nicotinamide phosphoribosyltransferase (NAMPT) and histone deacetylases (HDAC) as the agents with the highest activity. We validated the hits in an expanded set of neuroendocrine cell lines and examined the mechanisms of action. Results: In Kelly, NH-6, and NCI-H82, which are two neuroblastoma and one small cell lung cancer cell lines, respectively, metabolic studies suggested that cell death following NAMPT inhibition is the result of a reduction in basal oxidative phosphorylation and energy production. NAMPT is the rate-limiting enzyme in the production of NAD+, and in the three cell lines, NAMPT inhibition led to a marked reduction in the ATP and NAD+ levels and the catalytic activity of the citric acid cycle. Moreover, comparative analysis of the mRNA expression in drug-sensitive and -insensitive cell lines found less dependency of the latter on oxidative phosphorylation for their energy requirement. Further, the analysis of HDAC and NAMPT inhibitors administered in combination found marked activity using low sub-lethal concentrations of both agents, suggesting a synergistic effect. Conclusion: These data suggest NAMPT inhibitors alone or in combination with HDAC inhibitors could be particularly effective in the treatment of neuroendocrine neoplasms.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The new coordinate-tracking detector TREK based on drift chambers is being developed at National Research Nuclear University MEPhI to study inclined extensive air showers. To reconstruct the events ...with a high multiplicity from the data of drift chambers, the histogram method, which is designed to search for parallel tracks, is currently used. However, we observe afterpulses in the experimental data obtained using a coordinate-tracking unit based on drift chambers (CTUDC). The afterpulses lead to fake track reconstructions. To solve this problem, a new method is being developed using deep learning. This paper presents the results of the development of this method and its application to simulated data.
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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
Abstract
Tailings of mining and processing plants of Kryvbas are new areas of groundwater supply which have led to significant changes in the hydrodynamic and hydrogeochemical regimes of aquifers. ...The purpose of the research was to assess the degree of damage to the areas adjacent to the tailings of mining enterprises by dangerous The purpose of the research was to assess the degree of damage to the areas adjacent to the tailings of mining enterprises by dangerous hydrogeological processes, flooding and inundation. The quantitative regime of groundwater is in a stable state and corresponds to the modern conditions of operation of industrial facilities. During the research, chemical pollution in groundwater of all aquifers was recorded. At the time of research, there was an increased content of such microcomponents as: carcinogenic cadmium and nickel (up to 1.9-34 MPC; and 2.6-8.4 MPC, respectively); non-carcinogenic lead (up to 1.7-7 MPC); manganese (up to 2-320 MPC); bromine (up to 14-94 MPC) in the groundwater of all aquifers in the north. In the center, there was the accumulation of abnormally high concentrations of elements such as iron, manganese (up to 36-1420 MPC rate of 0.3 mg / dm
3
and 1.3-66 MPC rate of 0.1 mg / dm
3
, respectively, and a significant increase in the value of dry residue and the content of major macrocomponents in all aquifers. In the south for the modern period there is pollution of groundwater of the Quaternary and Neogene systems with such elements as total iron (15-2800 MPC), manganese (1.9-132 MPC), sometimes vanadium, cadmium. The geochemical essence of the formation of the chemical composition of polluted waters lies in the intensity of changes in the hydrogeochemical system and in the change in the migratory properties of chemical elements. The newest techniques and scientific developments on localization and the prevention of migration of heavy metals with the subsequent pollution of waters are required.
Investigation of lepton propagation through matter is of importance for cosmic-ray physics and neutrino astronomy. The diffractive scattering of virtual photons is considered as a process that leads ...to the energy loss of leptons emitting these photons. The interference between this process and bremsstrahlung makes a contribution that depends on the sign of the lepton charge.
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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, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The muon puzzle is an excess of muon bundles generated by primary cosmic rays (PCR) at energies above 10
eV compared to estimations that assume even a heavy composition of PCR. The appearance of such ...excess of muons can be caused both by cosmophysical (the change in the spectrum and composition of cosmic rays) and nuclear-physical (the changing features of the hadron interaction) reasons. To separate these two possibilities it is necessary to measure energy characteristics of muon bundles and their dependence on energy of primary particles. Today the complex NEVOD-DECOR is the only one for such type experiment conduction. To improve the conditions of this experiment a further development of the experimental complex is planned: construction of new coordinate-tracking detector TREK for increasing of the area and improving of spatial resolution of muon track detection, modernization of the Cherenkov water detector for optimization of its structure and improvement of accuracy of energy deposit of muon bundle measurement, inclusion of the installation NEVOD-EAS in the experiment for independent evaluation of primary particle energy.
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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
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