Investigation of the microstructure of the fine-grained YPO4_4:Gd ceramics with xenotime structure after Xe irradiation

The paper reports on the preparation of xenotime-structured ceramics by the Spark Plasma Sintering (SPS) method. Phosphates Y$_{0.95}$Gd$_{0.05}$PO$_4$ (YPO$_4$:Gd) were obtained by the sol-gel method. The synthesized nanopowders are collected in large agglomerates 10-50 mkm in size. Ceramics has a fine-grained microstructure and a high relative density (98.67%). The total time of the SPS process was approximately 18 min. High-density sintered ceramics YPO$_4$:Gd with a xenotime structure were irradiated with Xe$^{+26}$ ions (E = 167 MeV) to fluences of $1\times10^{12}$-$3\times 10^{13}$ cm$^{-2}$. Complete amorphization at maximum fluence was not achieved. As the fluence increases, an insignificant increase in the depth of the amorphous layer is observed. According to the results of grazing incidence XRD (GIXRD), with an increase in fluence from $1\times10^{12}$-$3\times 10^{13}$ cm$^{-2}$, an increase in the volume fraction of the amorphous structure from 20 to 70% is observed. The intensity of XRD peak 200 YPO$_4$:Gd after recovery annealing (700$^\circ$C, 18 h) reached a value of ~80% of the initial intensity I0.Comment: 16 pages, 10 figure

Напряженность иммунитета к кори в различных группах населения

Objective: to examine the state of the immunity to measles in different age groups.Materials and methods: In 2018, 4444 people were examined at the Diagnostic Center (virological). Among them, 3783 people were examined using the passive haemagglutination test for measles (manufactured by Pasteur Research Institute of Epidemiology and Microbiology, Russia). In the remaining 661 cases, the IgG to measles were detected using the enzyme-linked immunosorbent assay (ELISA) by VektoMeaseles IgG test (manufactured by Vector-Best, Russia). The correlation between the measles IgG level (ELISA) and the age was examined in 518 patients. Results: In this study, the immunity to measles was shown to be insufficient in all groups of observed people. Even among medical staff, nearly 10% had no protective level of measles antibodies. We have shown that the correlation between the measles IgG level and the age is statistically significant, so that the number of seronegative persons in different age groups differs significantly. Conclusion: The highest ratio of seronegative individuals was found in the age group between 18 and 25 years (52,33%), which can lead to serious measles outbreaks. Hence, this study confirms a strong need for additional immunization in all groups and especially in young population.Цель: изучить состояние иммунитета к кори в различных возрастных группах.Материалы и методы: В 2018 г. в Клинической инфекционной больнице им. С.П. Боткина в Городском консультативно-диагностическом центре (вирусологическом) было обследовано 4444 человека: у 3783 человек исследование было выполнено при помощи набора реагентов для реакции пассивной гемагглютинации к кори (производитель Научно-исследовательский институт эпидемиологии и микробиологии имени Пастера, Россия), в 661 случае был выполнен иммуноферментный анализ по определению IgG к вирусу кори с использованием тестсистемы «ВектоКорь IgG» (производитель АО «ВекторБест», Россия). Зависимость уровня антител к кори (метод иммуноферментного аналаиза) от возраста была исследована у 518 пациентов. Результаты: в данном исследовании было показано, что в настоящее время напряженность иммунитета во всех возрастных группах недостаточна. Даже среди медицинских работников был отмечен высокий процент серонегативных лиц. Показано наличие достоверной корреляции между уровнем IgG к кори и возрастом пациентов. Выявлены достоверные отличия по количеству серонегативных по кори лиц в различных возрастных группах. Заключение: значительное количество серонегативных лиц в возрастной группе до 25 лет создает серьезный риск возникновения эпидемии кори. Данное исследование показывает необходимость дополнительной иммунизации против кори всех групп населения и особенно лиц молодого возраста.

Аналіз методів та моделей оптимального розподілення навантажень між енергогенеруючими об’єтами

This paper gives consideration to the methods and models of the optimal distribution of loadings among energy generating facilities, in particular the method of dynamic programming; two-step method of the optimal distribution of loadings among the energy blocks using the so-called special reference points; methods and models in which the form of the fuzzy description of the factors of the data uncertainty is based on the theory of fuzzy sets; methods and models of the excess of versions; methods and models of relative increments in the fuel flow rate and their combinations; the heuristic method of the solution of the problem of the loading distribution using the limitations of the minimum and maximum electric loadings of energy blocks; the optimization method of the projection of the Rosen gradient, etc. Advantages and drawbacks of the methods and models were shown. It was shown that the methods and models used for the optimization of the distribution of loadings among energy generating facilities require improvement, which makes the development and improvement of the mathematical and algorithmic software used by the automated systems of the control of technological processes of the energy blocks of nuclear power stations and thermal power stations a vital problem.Рассмотрены методы и модели оптимального распределения нагрузок междуэнергогенерирующими объектами. Указаны достоинства и недостатки этих методов и моделей. Показананеобходимость совершенствования методов и моделей оптимизации распределения нагрузок междуэнергогенерирующими объектами, что делает актуальными разработки и усовершенствованиематематического и алгоритмического обеспечения, находящегося в распоряжении автоматизированныхсистем управления технологическими процессами энергоблоков АЭС и ТЭС.Розглянуто методи та моделі оптимального розподілу навантажень між енергогенеруючими об\'єктами. Вказані достоїнства і недоліки методів. Показано необхідність удосконалення методів і моделей оптимізації розподілу навантажень між енергогенеруючими об\'єктами, що робить актуальними розробки та удосконалення математичного та алгоритмічного забезпечення, яке знаходиться у розпорядженні автоматизованих систем управління технологічними процесами енергоблоків АЕС та ТЕС

Measles immunity in different population groups

Objective: to examine the state of the immunity to measles in different age groups.Materials and methods: In 2018, 4444 people were examined at the Diagnostic Center (virological). Among them, 3783 people were examined using the passive haemagglutination test for measles (manufactured by Pasteur Research Institute of Epidemiology and Microbiology, Russia). In the remaining 661 cases, the IgG to measles were detected using the enzyme-linked immunosorbent assay (ELISA) by VektoMeaseles IgG test (manufactured by Vector-Best, Russia). The correlation between the measles IgG level (ELISA) and the age was examined in 518 patients. Results: In this study, the immunity to measles was shown to be insufficient in all groups of observed people. Even among medical staff, nearly 10% had no protective level of measles antibodies. We have shown that the correlation between the measles IgG level and the age is statistically significant, so that the number of seronegative persons in different age groups differs significantly. Conclusion: The highest ratio of seronegative individuals was found in the age group between 18 and 25 years (52,33%), which can lead to serious measles outbreaks. Hence, this study confirms a strong need for additional immunization in all groups and especially in young population

On the Relationship between the Omori and Gutenberg-Richter Parameters in Aftershock Sequences

International audienceAbstract—The issues concerning the relationship between two self-similarity parameters—the Gutenberg-Richter b- and Omori p-values—in the aftershock sequences are explored. In the laboratory experiments, under fracture initiation in the rock by sharp jumps in the axial stress, a correlation between the p- and b-values is revealed in the fracture relaxation regimes similar to aftershocks. The correlation observed in the experiments on water-saturated sandstone samples with the preliminarily formed faults is negative and clearly pronounced. The correlation in the case of dry samples of migmatite and concrete proved to be positive but its statistical significance is lower than for the wet samples. The analysis of the literature data on detecting the connection between parameters p and b in the natural aftershock sequences shows that the reported results are heterogeneous. Some authors conclude that these parameters are connected and that both positive and negative correlation is noted between them. Other authors present evidence suggesting the absence of any correlation. Our study of the natural aftershocks based on the data of regional earthquake catalogs has shown that the statistical estimates of the Gutenberg-Richter and Omori parameters are fairly sensitive to the quality and homogeneity of the input data. The key factors affecting the estimation quality of these parameters are established, and the procedure for selecting the aftershock catalogs for subject analysis is developed. The results of statistical estimating the Gutenberg-Richter and Omori parameters in the aftershock processes in the regions with different types of the tectonic regimes—subduction zones and regions of shear transform faults—have shown that that the correlation of these parameters in the subduction zones can be positive and negative either. In the zones of the transform faults, the connection between these parameters is not detected. Our study generalizes K. Scholtz's idea that the Omori law can be explained by the superimposition of the relaxation processes having different relaxation times. According to the generalized model, the different sign of the correlation between the self-similarity parameters in the aftershock processes correspond to the different relaxation mechanisms with different types of the dependence of the relaxation time on the "size" of the relaxator. It is currently unclear which particular mechanisms are implemented in the aftershock processes. The relationship between the Omori and Gutenberg-Richter parameters revealed by our laboratory experiments and field studies (positive correlation, negative correlation, or lack of correlation) may indicate the implementation of different relaxation mechanisms in some or other particular conditions

Latent myocardial damage after cardiopulmonary resuscitation in a teenager without prior cardiac disease

Cardiopulmonary resuscitation is an integral part of intensive care in children and adolescents with a number of diseases, most commonly with congenital heart disease, critical cardiac arrhythmias, or severe traumas. This procedure can cause a number of complications, most of them are still completely unstudied, and many of them are associated with the underlying disease. We have a unique case report of a 14-year-old boy without any cardiac disease, who underwent extensive resuscitative measures, including closed-chest massage, tracheal intubation with mechanical ventilation, as well as a few electrical defibrillations with transient myocardial injury

Status and initial physics performance studies of the MPD experiment at NICA

The Nuclotron-based Ion Collider fAcility (NICA) is under construction at the Joint Institute for Nuclear Research (JINR), with commissioning of the facility expected in late 2022. The Multi-Purpose Detector (MPD) has been designed to operate at NICA and its components are currently in production. The detector is expected to be ready for data taking with the first beams from NICA. This document provides an overview of the landscape of the investigation of the QCD phase diagram in the region of maximum baryonic density, where NICA and MPD will be able to provide significant and unique input. It also provides a detailed description of the MPD set-up, including its various subsystems as well as its support and computing infrastructures. Selected performance studies for particular physics measurements at MPD are presented and discussed in the context of existing data and theoretical expectations