Possibility to study eta-mesic nuclei and photoproduction of slow eta-mesons at the GRAAL facility

A new experiment is proposed with the aim to study eta-mesic nuclei and low-energy interactions of eta with nuclei. Two decay modes of eta produced by a photon beam inside a nucleus will be observed, namely a collisional decay \eta N \to \pi N inside the nucleus and the radiative decay \eta \to \gamma \gamma outside. In addition, a collisional decay of stopped S_{11}(1535) resonance inside the nucleus, S_{11}(1535) N \to N N, will be studied. The experiment can be performed using the tagged photon beam at ESRF with the end-point energy 1000 MeV and the GRAAL detector which includes a high-resolution BGO calorimeter and a large acceptance lead-scintillator time-of-flight wall. Some results of simulation and estimates of yields are given.Comment: 20 pages, 19 figure

Gas Purity effect on GEM Performance in He and Ne at Low Temperatures

The performance of Gas Electron Multipliers (GEMs) in gaseous He, Ne, He+H2 and Ne+H2 was studied at temperatures in the range of 3-293 K. This paper reports on previously published measurements and additional studies on the effects of the purity of the gases in which the GEM performance is evaluated. In He, at temperatures between 77 and 293 K, triple-GEM structures operate at rather high gains, exceeding 1000. There is an indication that this high gain is achieved through the Penning effect as a result of impurities in the gas. At lower temperatures the gain-voltage characteristics are significantly modified probably due to the freeze-out of these impurities. Double-GEM and single-GEM structures can operate down to 3 K at gains reaching only several tens at a gas density of about 0.5 g/l; at higher densities the maximum gain drops further. In Ne, the maximum gain also drops at cryogenic temperatures. The gain drop in Ne at low temperatures can be re-established in Penning mixtures of Ne+H2: very high gains, exceeding 104, have been obtained in these mixtures at 30-77 K, at a density of 9.2 g/l which corresponds to saturated Ne vapor density at 27 K. The addition of small amounts of H2 in He also re-establishes large GEM gains above 30 K but no gain was observed in He+H2 at 4 K and a density of 1.7 g/l (corresponding to roughly one-tenth of the saturated vapor density). These studies are, in part, being pursued in the development of two-phase He and Ne detectors for solar neutrino detection.Comment: 4 pages, 7 figure

Creation and decay of eta-mesic nuclei

First experimental results on photoproduction of eta-mesic nuclei are analyzed. In an experiment performed at the 1 GeV electron synchrotron of the Lebedev Physical Institute, correlated pi+n pairs arising from the reaction gamma + 12C -> N + eta(A-1) -> N + pi+ + n + (A-2) and flying transversely to the photon beam have been observed. When the photon energy exceeds the eta-meson production threshold, a distribution of the pi+n pairs over their total energy is found to have a peak in the subthreshold region of the internal-conversion process eta p -> pi+ n which signals about formation of eta-mesic nuclei.Comment: 6 pages, 6 figures. Talk at CIPANP, May 2000, Quebe

Experimental Investigation of the Nature of the Knee in the Primary Cosmic Ray Energy Spectrum with the GAMMA experiment

We present preliminary results obtained by a novel difference method for the study of the nature of the knee in the energy spectrum of the primary cosmic radiation. We have applied this method to data from the GAMMA experiment in Armenia. The analysis provides evidence for the possible existence of a nearby source of primary cosmic rays in the Southern hemisphere.Comment: 17 pages, 5 figure

Effects of dimephosphone on skin survival in conditions of reduced blood circulation

The search for and creation of drugs with dermatoprotective and metabotropic activity is one of the priorities of modern diabetology. Synthetic organophosphorus compounds with no anticholinesterase activity, to which dimephosphone belongs to, deserve great attention in this respec

GEM operation in helium and neon at low temperatures

We study the performance of Gas Electron Multipliers (GEMs) in gaseous He, Ne and Ne+H2 at temperatures in the range of 2.6-293 K. In He, at temperatures between 62 and 293 K, the triple-GEM structures often operate at rather high gains, exceeding 1000. There is an indication that this high gain is achieved by Penning effect in the gas impurities released by outgassing. At lower temperatures the gain-voltage characteristics are significantly modified probably due to the freeze-out of impurities. In particular, the double-GEM and single-GEM structures can operate down to 2.6 K at gains reaching only several tens at a gas density of about 0.5 g/l; at higher densities the maximum gain drops further. In Ne, the maximum gain also drops at cryogenic temperatures. The gain drop in Ne at low temperatures can be reestablished in Penning mixtures of Ne+H2: very high gains, exceeding 10000, have been obtained in these mixtures at 50-60 K, at a density of 9.2 g/l corresponding to that of saturated Ne vapor near 27 K. The results obtained are relevant in the fields of two-phase He and Ne detectors for solar neutrino detection and electron avalanching at low temperatures.Comment: 13 pages, 14 figures. Accepted for publishing in Nucl. Instr. and Meth.

Air Pollen Monitoring in a Specific Region as a Part of the Pollinosis Prevention

Background: The prevalence and severity of allergic diseases, including pollinosis, are increasing worldwide. Hay fever develops due to the complex interaction of genes and manifests itself due to exogenous factors. The main environmental etiology of allergy is plant pollen. Continuous study and analysis of the air pollen spectrum constitute the basis of air monitoring and are important in developing preventive measures for allergic diseases.   Objective: To perform an air pollen monitoring in Kr snodar and to assess the treatment of patients with pollinosis in various cities and districts of the Krasnodar Region according to the Krasnodar Regional Allergy Center data.   Materials and methods: We retrospectively analyzed the patients seeking medical care due to allergy in the Krasnodar Region using the statistical data obtained in 2022 from the Krasnodar Regional Allergy Center. We assessed the effects of air pollen pollution according to the data of air pollen monitoring in Krasnodar during the main activity of herbaceous plants’ taxa (from April 1, 2022 to October 31, 2022). We used AeRobiology and Microsoft Excel 2010 tools for data processing and development of the main parameters of the pollen season.   Results: According to the Krasnodar Regional Allergy Center data, there were 37,212 people diagnosed with J45.0, J46 and 20,012 people diagnosed with J30.1-30.4 in 2022. We identified 8 allergenic taxa of herbaceous plants in the Krasnodar air. We found that the total seasonal pollen concentration increased by an average of 1.8 in 2022 compared to previous monitoring periods in 2018-2021.   Conclusions: Comparative assessment of the prevalence of pollinosis and the air pollen monitoring are important for effective medical care

Mafusol and its combination with REXOD as correctors of reduced blood circulation in the skin associated with normoglycemia or diabetes mellitus complicated by exogenous hypercholesterolemia

The search for and development of new highly active medications and their combinations of the appropriate direction of action remains an urgent problem due to the complications of diabetes mellitus, especially burdened with atherosclerosis, including skin and vascular lesion