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Abstract The results of experimental studies of the interaction of the S-protein with a monohetaryl-substituted porphyrin containing a benzimidazole residue are presented. It has been revealed that the S-protein forms high-affinity complexes with the specified porphyrin. The porphyrin binding by the SARS-CoV-2 S-protein has proceeded stepwise; at the first stage, the driving force of the complexation is electrostatic interaction between the surface negatively charged regions of the protein and cationic substituents of the porphyrin. At the second stage, the target complex of the S-protein with the porphyrin is formed. It has been established that the introduction of 5-[4′-(N-methyl-1,3-benzimidazol-2-yl)phenyl]-10,15,20-tri-(N-methyl-3′-pyridyl)porphyrin triiodide into a solution of the S-protein complex with the angiotensin-converting enzyme leads to the replacement of the latter with the porphyrin. Displacement of the angiotensin-converting enzyme from the complex with the S-protein under the action of 5-[4′-(N-methyl-1,3-benzimidazol-2-yl)phenyl]-10,15,20-tri-(N-methyl-3′-pyridyl)porphyrin triiodide is the experimental evidence for the porphyrin binding at the receptor-binding domain of the S-protein.

The multistage purposeful synthesis of 5,15-bis(4'-l

In comparison with calculations, the excess of multimuon events found in many experiments at ultrahigh energies of extensive air showers (EASs) cannot be explained using modern models of hadron interactions. The existence of muon excess is called the muon puzzle. One of the ways to solve this problem is to study the energy characteristics of the EAS muon component. For this purpose, the energy deposit of cosmic ray muon bundles is measured in the NEVOD–DECOR experiment. Registration of muon bundles in a wide range of zenith angles allows one to explore a wide range of energies of the primary particles of cosmic rays (from 10 to 1000 PeV) within a single experiment. The results of measurements of the energy deposit of muon bundles over a long observation period are presented.

Data on cosmic ray muon bundles accumulated at the NEVOD-DECOR complex over the period from May 2012 to December 2018 have been analyzed. Local muon density spectra at various zenith angles have been reconstructed and compared with CORSIKA-based simulations. At large zenith angles and high muon multiplicities corresponding to primary particle energies more than about 3 × 1017 eV an excess of multi-muon events compared to simulations is clearly seen. Present data are compatible with the expectation for recent LHC-adjusted hadron interaction models only under assumption of extremely heavy (iron group nuclei) primary composition. The assumption of a heavy composition is however in contradiction with other EAS observables, such as maximum depth and its fluctuations.

Investigations of the energy loss of muon bundles are being conducted at the Experimental complex NEVOD. Such investigations are directed to detailed study of “muon puzzle” (the excess of multi-muon events observed in several cosmic ray experiments at ultra-high energies). Results of measurements of the muon bundle energy deposit during a long period of observations in primary cosmic ray energy range 10–1000 PeV have been obtained and have been compared with simulations performed on the basis of the CORSIKA code.

The neutrino telescope IceCube is capable to reconstruct the energy spectrum of muons in very high energy region by means of measurements of muon-induced cascades. To compare with experimental data, the expected spectra of cascades were theoretically estimated. Calculations were performed for two variants of muon spectrum on the ice surface: a simple power-law energy spectrum with a differential slope index −3.7, and a composite spectrum combined of two power spectra with differential indexes −3.7 and −2.7. The differential spectra of cascades for different zenith angles and integral cascade spectra calculated for two variants of muon spectra are discussed.

An algorithm is described for the operation of a program that simulates processes of the energy loss of high-energy muons. Results from simulating the spectra of muons and cascade showers generated by muons at water depths of 4.5–5.5 km are discussed.

The existence of an excessive number of multimuon events observed in many experiments at ultrahigh EAS energies (above 1017 eV) relative to calculations cannot be explained using modern models of hadronic interactions. One way of solving the problem of muon excess is to study the energy characteristics of the EAS muon component. Results are presented from measurements of muon bundle energy characteristics over 7 years of observations. The experimental dependences are compared to results from simulation done with the CORSIKA software package.

Data of the NEVOD-DECOR experiment on investigations of inclined cosmic ray muon bundles for a long time period (May 2012 – March 2021) are presented. Their comparison with the results of calculations based on simulations of EAS muon component allows one to study the behavior of the energy spectrum and mass composition of primary cosmic rays and/or to check the validity of hadron interaction models in a wide energy range from about 10^16 to more than 10^18 eV. The analysis showed that the observed intensity of muon bundles at primary particle energies of about 10^18 eV and higher can be compatible with the expectation only under the assumption of an extremely heavy mass composition of cosmic rays. This conclusion is consistent with data of a number of other experiments investigating the muon component of air showers at ultra-high energies. On the contrary, measurements of the depth of the shower maximum in the atmosphere (Xmax) in the experiments using air fluorescence technique favor a light mass composition of primary cosmic rays at these energies. This contradiction (so-called “muon puzzle”) cannot be resolved without serious changes of the existing hadron interaction models.

Energy characteristics of the muon component of extensive air showers (EASes) are investigated at the NEVOD experimental complex in order to solve the problem of a detected excess of muons in EASes at ultrahigh energies, relative to simulation results. The dependences of the energy deposit of muon bundles on the zenith angle and the local muon density are obtained for primary energies of 10–1000 PeV. The results from comparing the data to simulations performed with the CORSIKA program are presented.

As part of an in-depth investigation of the muon excess observed in ultrahigh-energy cosmic rays, one needs to measure the energy characteristics of muon component of extensive air showers (EAS). The mean muon energy can be estimated from the energy deposited in the detector by the muon bundles. In the NEVOD–DECOR experiment, the local muon density and the shower-arrival direction are measured with a track-coordinate detector, and the deposited energy is measured in the Cherenkov calorimeter. The results of the measurements carried out in 17400 h of detector operation are compared with those of the simulation based on the CORSIKA package.

An experiment on the measurements of the energy deposit of inclined cosmic ray muon bundles is being conducted at the experimental complex NEVOD (MEPhI). The complex includes the Cherenkov water calorimeter with a volume of 2000 m3 and the coordinate-tracking detector DECOR with a total area of 70 m2. The DECOR data are used to determine the local muon densities in the bundle events and their arrival directions, while the energy deposits (and hence the average muon energy loss) are evaluated from the Cherenkov calorimeter response. Average energy loss carries information about the mean muon energy in the bundles. The detection of the bundles in a wide range of muon multiplicities and zenith angles gives the opportunity to explore the energy range of primary cosmic ray particles from about 10 to 1000 PeV in the frame of a single experiment with a relatively small compact setup. Experimental results on the dependence of the muon bundle energy deposit on the zenith angle and the local muon density are presented and compared with expectations based on simulations of the EAS muon component with the CORSIKA code.

Data of NEVOD-DECOR experiment on investigations of inclined cosmic ray muon bundles for a long time period (May 2012 – May 2020) are presented. Their comparison with the results of calculations based on simulations of extensive air shower hadron and muon components is carried out. The analysis showed that the observed intensity of muon bundles at primary particle energies of about 1018 eV and higher can be compatible with the expectation only under the assumption of an extremely heavy mass composition of cosmic rays. On the contrary, measurements of the depth of the shower maximum in the atmosphere in the experiments using air fluorescence technique, favour a light mass composition of primary cosmic rays at these energies.

Experimental data on the energy deposits of muon bundles in inclined extensive air showers (EASes), obtained at the NEVOD–DECOR installation over a long period of time, are presented. The experimental data are compared to calculations based on simulating an EAS’s muon component using the CORSIKA code.

An experiment on the measurements of the Cherenkov light yield from inclined cosmic ray muon bundles in water is being conducted at the Experimental complex NEVOD (MEPhI). The total number of Cherenkov photons is nearly proportional to the muon energy deposit (including secondary particles produced by muons and cascades from them) within the detector volume. Since at muon energies above a hundred GeV the energy loss is almost linearly related to the energy of muons, the average energy loss of the bundles carries information about the mean muon energy in such events. The complex includes the Cherenkov water calorimeter NEVOD with a volume of 2000 m3 and the coordinate-tracking detector DECOR with a total area of 70 m2. DECOR data are used to determine the local muon densities in the bundle events and their arrival directions, while the energy deposits are evaluated from the Cherenkov calorimeter response. The detection of the bundles in a wide range of muon multiplicities and zenith angles gives the opportunity to explore the energy range of primary cosmic ray particles from about 10 PeV to 1000 PeV and even higher in frame of a single experiment. Experimental results on the dependence of the muon bundle energy deposit on the zenith angle and the local muon density are presented and compared with expectations based on simulation of the EAS muon component by means of the CORSIKA code.

In order to solve the problem of the excess of multi-muon events observed in several cosmic ray experiments at ultra-high energies (so-called ‘muon puzzle’), investigations of the energy characteristics of the muon component of extensive air showers (EAS) are required. A possible approach to such investigations is the measurement of the energy deposit of muon bundles in the detector, which provides information on the mean muon energy. In the experiment being now conducted at the NEVOD-DECOR complex, the local muon density and EAS arrival direction are determined according to the data of the coordinate-tracking detector DECOR, whereas the energy deposit is measured by means of the Cherenkov water calorimeter NEWOD. Simultaneous detection of muon bundles in a wide range of zenith angles and muon multiplicities ensures exploration of primary particle energy region of 10^16 – 10^18 eV and even higher. Results of the measurements of the energy deposit of the inclined muon bundles at various zenith angles based on the data accumulated during more than 29,000 h observations over the period from May 2012 to February 2017 are presented and compared with simulations performed by means of the CORSIKA program.

To solve the problem of the excess of multi-muon events observed in several cosmic ray experiments at ultra-high energies (so-called “muon puzzle”), an analysis of the energy characteristics of the muon component of extensive air showers (EAS) is required. A possible approach to such investigations is the measurement of the energy deposit of muon bundles in the detector, which provides information on the mean muon energy. In the experiment now being conducted at the NEVOD-DECOR complex, the local muon density and EAS arrival direction are determined according to the data of the coordinate-tracking detector DECOR, whereas the energy deposit is measured by means of the Cherenkov water calorimeter NEVOD. Results of the measurements of the energy deposit of inclined muon bundles based on the data accumulated during more than 23,200 h observations in 2012 – 2016 are presented and compared with simulations performed by means of the CORSIKA code.

Change of the energy characteristics of muon bundles with an increase of the primary cosmic ray particles energy can be a key to solving the problem of muon excess in the extensive air showers (EAS) observed in a number of experiments. In this work the data on the energy deposit of multi-muon events in a wide range of zenith angles (and as a consequence in a wide range of primary particles energies) obtained with NEVOD-DECOR setup over a long time period are presented. The experimental data are compared with the results of simulations of EAS muon component performed using CORSIKA code., Comment: XXV ECRS 2016 Proceedings - eConf C16-09-04.3

The method of sections was used to study the solubility of the components of the LiClO4 (LiBF4)-diethyl carbonate (DEC)-propylene carbonate (PC) ternary system at 25°C. The phase diagrams of the systems were plotted and discussed. At this temperature, the solid phase of the LiClO4-DEC-PC system is pure salt while that of the LiBF4-DEC-PC system is composed of LiBF4 and its LiBF4 · DEC and LiBF4 · PC crystal solvates. The compositions of the crystallized solid phases obtained graphically by using the method of sections were confirmed by XRD analysis.

Bi-, tri-, and tetradentate macroheterocylic ligands, i.e., structural analogs of phthalocyanine, are studied by X-ray photoelectron spectroscopy. The X-ray photoelectron spectra of N1s lines of the nitrogen atoms of these compounds are analyzed. The binding energies and integrated intensities of N1s lines of the nitrogen atoms are determined and the effective charges on the nitrogen atoms are calculated. The structures of bi-, tri-and tetradentate macroheterocyclic ligands containing isoindole, benzene, and pyridine fragments are established on the basis of the data obtained.

We found that extracts from the leaves of medicinal comfrey and cowparsnip strongly inhibit the germination of Erysiphe graminisconidia and uredospores of Puccinia graminis. Spraying wheat seedlings with these extracts, in contrast to the irrigation of soil, markedly diminished infection in plants with powdery mildew. Antifungal activity in vitroand protective activity (when plants were sprayed) correlated with the level of phenolic compounds in these extracts. Experiments with healthy plants have demonstrated that the photosynthetic apparatus of wheat plants is stimulated by extracts. Spraying seedlings with the extracts resulted in an increased rate of O2evolution calculated per unit of chlorophyll, an increase in the ratio (FM– FT)/FTin the experiments that recorded slow fluorescence induction, an increase in the relative light intensity of band A, and a decrease of relative intensity of band Cin experiments with thermoluminescence of wheat leaves. These results provide evidence that the protective activity of comfrey and cowparsnip extracts is associated with their action on the pathogenic fungus and with the activation of natural defense reactions of the host plant.

The effect of UV-radiation (240–390 nm, 151–4530 J/m2) on structural changes in human carboxyhemoglobin is studied. Photodissociation of CO ligand from heme and conversion of hemoprotein into oxyhemoglobin and methemoglobin were accompanied by changes in spectral and electrophoretic characteristics (number, mobility, and content of fractions) of the studied hemoprotein.

Temporal changes in the intensity of muon bundles produced as a result of interactions of primary cosmic ray particles with energies of the order of 1015 eV and detected at the ground level are analyzed. Seasonal variations, barometric and temperature effects, and correlations with the altitudes of various levels of residual pressure are considered. It is shown that muon bundle intensity variations are well explained in frame of a simple mechanism related with changes of the muon lateral distribution function at the observation level caused by geometrical changes of the effective altitude of the formation of the bundles.

Investigations of the energy characteristics of muon component with the increase of the primary cosmic rays energy can be a key to solving 'muon puzzle' - the problem of excess of EAS muons (observed in several experiments at high - ALEPH, DELPHI - and ultrahigh energies - DECOR, Pierre Auger Observatory) in comparison with the expected flux. The measurements results of the energy deposit of inclined muon bundles in water depending on the zenith angle and the local density of muons are presented. As a measure of the energy deposit, the total number of photoelectrons registered by PMTs of the Cherenkov water calorimeter NEVOD was used. The local density of muons, which gives an estimate of the energy of primary particles was obtained from the data of coordinate-tracking detector DECOR. The experimental data are compared with the results of calculations based on simulations of the muon component of EAS by means of the CORSIKA code.

We have studied the effects of the antibiotic trichothecin (Trichothecium roseunm) and the systemic fungicide triadimefon on the parasitic activity of Puccinia graminis and on metabolic processes of plants. Trichothecin is an antifimgial antibiotic formed by Trichothecium roseum. This antibiotic is a ketone with empirical formula C19H24O5. Triadimefon is a systemic fungicide (3,3-dimethil-1/1H-1,2,4,-trizolil/4-chlorophenoxi/buthanol-2). The experiments were performed on isogenic lines of wheat Triticum aestivum L. cv. Markiz with different resistance to stem rust. Two strains of wheat were studied: the resistant strain with gene Sr Tt and susceptible strain with gene Sr 9B. Physiological and biochemical tests were performed on the first leaves of wheat seedlings of uninfected and infected plants. The concentrations of trichothecin and triadimefon were selected on the basis of data of inhibitory effect on activity of P.graminis uredospores germinating in moist camera on the surface of 1% water. The solution concentration of trichothecin and triadimefon which strongly suppressed the uredospores germinating on water agar were chosen for the experiments with plants. The influence of the preparation on the degree of defeat was controlled by the number of pustules on leaves, which appeared om 8-10-th day after the invasion. The number of pustules was counted on 20–30 plants.