165 research outputs found
Ragweed pollen rain impact on allergy rate and severity in Krasnodar: a three-year non-randomised controlled study
Background. The main hay fever agent in Krasnodar Krai is ragweed pollen (Ambrosia gen.). An important alerting guide for medical practitioners and allergic citizens is the seasonal anthetic calendar and pollen peak times.Objectives. Obtaining of relevant data on ragweed pollen air contamination rate in Krasnodar in a three-year-dynamics (2018–2020) to estimate the anthetic activity correlation with abiotic and anthropogenic factors and the role of pollen indicators in allergic morbidity.Methods. We surveyed the daily average ragweed pollen values in Krasnodar air. Allergic medical visits were analysed in terms of the ragweed anthetic activity and pollen air contamination of the city.Results. A maximal daily average ragweed pollen peak occurs in August: 663.35 p.g./m3 in 2018, 209.89 p.g./m3 in 2019, 80.62 p.g./m3 in 2020. Numbers of medical visits for pollinosis per a selected municipal medical facility: 314 in 2018, 335 in 2019 and 146 in 2020, with a peak period in September--October. Analyses of the air pollution impact on ragweed pollen production revealed a correlation between the pollen rate and values of CO (correlation coefficient r-0.356), NH3 (r-0.198) and dust pollution (r-0.361) in July, August, September and October 2018–2020.Conclusion. Analyses of climatic factors uncovered clear patterns: strongest anthesis corresponds to minimal humidity (<60%), the pollen grain content diminishes with lower humidities dropping to minimal with precipitations and increases at temperatures 20 °C and above. No significant dependency was observed between air pollution and the allergic pollen content. Anthesis in ragweed moderately correlates with the rate of medical visits
Experimental investigation of high-energy photon splitting in atomic fields
The new data analysis of the experiment, where the photon splitting in the
atomic fields has been observed for the first time, is presented. This
experiment was performed at the tagged photon beam of the ROKK-1M facility at
the VEPP-4M collider. In the energy region of 120-450 MeV, the statistics of
photons incident on the BGO target was collected. About 400
candidates to the photon splitting events were reconstructed. Within the
attained experimental accuracy, the experimental results are consistent with
the cross section calculated exactly in an atomic field. The predictions
obtained in the Born approximation significantly differ from the experimental
results.Comment: 11 pages, 6 figures, LaTe
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
Наследование и технологическое обеспечение эксплуатационных свойств изделий с покрытиями
The results of studies on technological assurance and performance properties of machine parts with weld and spray-coating are presented. It is shown that the parameters of state of the surface layer and the operational properties of coated parts, along with processing conditions, are determined by the peculiarities of the structure and properties of the deposited or sputtered material.Представлены результаты исследований по технологическому обеспечению эксплуатационных свойств деталей машин с наплавленным и напыленным покрытием. Показано, что параметры состояния поверхностного слоя и эксплуатационные свойства деталей с покрытиями наряду с условиями обработки определяются особенностями структуры и свойств наплавленного или напыленного материала
Influence of Gamma-Ray Emission on the Isotopic Composition of Clouds in the Interstellar Medium
We investigate one mechanism of the change in the isotopic composition of
cosmologically distant clouds of interstellar gas whose matter was subjected
only slightly to star formation processes. According to the standard
cosmological model, the isotopic composition of the gas in such clouds was
formed at the epoch of Big Bang nucleosynthesis and is determined only by the
baryon density in the Universe. The dispersion in the available cloud
composition observations exceeds the errors of individual measurements. This
may indicate that there are mechanisms of the change in the composition of
matter in the Universe after the completion of Big Bang nucleosynthesis. We
have calculated the destruction and production rates of light isotopes (D, 3He,
4He) under the influence of photonuclear reactions triggered by the gamma-ray
emission from active galactic nuclei (AGNs). We investigate the destruction and
production of light elements depending on the spectral characteristics of the
gamma-ray emission. We show that in comparison with previous works, taking into
account the influence of spectral hardness on the photonuclear reaction rates
can increase the characteristic radii of influence of the gamma-ray emission
from AGNs by a factor of 2-8. The high gamma-ray luminosities of AGNs observed
in recent years increase the previous estimates of the characteristic radii by
two orders of magnitude. This may suggest that the influence of the emission
from AGNs on the change in the composition of the medium in the immediate
neighborhood (the host galaxy) has been underestimated.Comment: 13 pages, 13 figures, 3 table
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