Effect of the superconducting wiggler on the DELSY beam dynamics

The project DELSY is being under development at JINR, Dubna, Russia. This synchrotron radiation source is dedicated to the investigation on condensed matter physics, atomic physics, biology, medicine, chemistry, micromechanics, lithography and others. The storage ring DELSY is an electron storage ring with the beam energy 1.2 GeV and 4 straight sections to accommodate accelerator equipment and insertion devices. One of the straight sections is intended for a 10 T superconducting wiggler (wavelength shifter) and one for the undulator with 150 periods and a magnetic field of 0.75 T. The wiggler will influence many aspects of beam dynamics: linear motion, dynamic aperture, emittance, damping times etc. The problem is rather serious for the DELSY machine because the energy of the electron beam is small while the wiggler's magnetic field is strong. In this paper we consider two models of the wiggler's magnetic field with and without the focusing caused by the sextupolar field of the wiggler as we need to develop the requirements to the wiggler design. We study the influence of the 10 T wiggler on the beam dynamics in the DELSY storage ring and propose a possible scheme to cure it. The combined work of the insertion device is presented too.Comment: 17 pages, submitted to journal NIM

Обеспечение безопасности при обращении с ядерными материалами на заводе по изготовлению твэл

Объектом исследования являются вопросы организации и функционирования систем физической защиты. Цель работы – формирование условий для безопасной эксплуатации ядерного объекта. В процессе исследования проводился анализ нормативно-правовых документов по вопросам организации и функционирования систем физической защиты и систем учета и контроля ядерных материалов на ядерном объекте, формирование требований к оснащению элементами комплекса инженерно- технических средств физической защиты внутренней зоны и периметра ядерного объекта. Был проведен анализ спектральных характеристик неизвестного источника ионизирующего излучения. В результате был получен проект по оснащению комплексом инженерно- технических средств физической защиты периметра и внутренней зоны ядерного объекта. Был определен изотопный состав неизвестного источника ионизирующего излучения, подсчитана его масса и активность.The object of research is the organization and functioning of physical protection systems. The work purpose – to create conditions for the safe operation of a nuclear facility. In the process of investigation the analysis of normative-legal documents on the organization and functioning of systems of physical protection and systems for accounting and control of nuclear materials at the nuclear facility, development of requirements for equipping of the complex of technical means of physical protection of the internal area and perimeter of a nuclear facility. An analysis was conducted of the spectral characteristics of an unknown source of ionizing radiation. The result was obtained the project to equip the complex of technical means of physical protection of the perimeter and internal zones of a nuclear facility. Was determined the isotopic composition of an unknown source of ionizing radiation, calculated its mass and activity

ИЗМЕНЧИВОСТЬ ЗИМНЕГО СТОКА РЕКИ ОКА В ЗАВИСИМОСТИ ОТ ИЗМЕНЕНИЯ КЛИМАТА

Response of a river flow in a winter low-water period to the climate changes is analyzed by the example of theOkaRiver(245 thousand km2). The analysis was done for each individual month from December to March during the period 1980–2015. The data were obtained for the hydrometric section Oka–Gorbatov. The following climatic characteristics were used for the analysis: 1) the number of days with positive air temperatures; 2) the temperature of the upper soil layer; 3) the sum of precipitation (data of meteorological station); 4) water equivalent of snow (the data from the satellite ESA GlobSnow, SWE version 2). Accuracy of the satellite data was estimated with respect to the observational data. In 1981–2010, significant increase in winter runoff occurred in December and March. This period was divided into two phases: 1) the end of the 20th century which was characterized by increasing of precipitation, the soil temperature, number of days with positive temperatures, and that resulted in the growth of the water equivalent of snow; 2) the beginning of the 21st century – by significant fluctuation in precipitation, number of days with positive temperatures as well as by a drop in the soil temperature and water equivalent of snow. The runoff volume was found to be in a direct relationship with the number of days with positive temperatures, the soil temperature, the precipitation sum, and in the inverse relationship with the water equivalent of snow. Both, the regression and dispersion analyses indicated that the above set of climatic characteristics was sufficient to explain changes in the winter runoff. According to the degree of influence on the winter runoff, these characteristics can be ranked as follows: the number of days with positive temperatures; the average soil temperature; the water equivalent of snow; the precipitation sum. The effect of the water equivalent on the runoff becomes significant from midwinter and remains the most significant factor by the end of snowmelt.Определена реакция зимнего стока рек в бассейне р. Ока (притока Волги) в 1981–2010 гг. на изменение климатических характеристик: суммы осадков, числа дней с положительными температурами воздуха и температуры верхнего слоя почвы, полученных по данным метеостанций, а также водного эквивалента снега, определённого по данным спутникового зондирования. Значимое увеличение зимнего стока в бассейне Оки наблюдается в периоды становления зимнего снежного покрова и начале снеготаяния

Влияние релаксационной прочности зерен и межзеренных границ в котельных сталях на работоспособность поверхностей нагрева

Представлены экспериментальные результаты исследований отечественной разработки аустенитной хромомарганцевой стали 10Х13Г12С2Н2Д2Б (Ди-59). На основе рентгенометрии показано, что осцилляции внутренних напряжений при циклическом изменении температуры, сопровождающиеся процессами релаксации при перемене знака, окажут существенное влияние на прочностные характеристики и послужат причиной термической усталости металла, а критерии релаксации напряжений и условия их протекания станут определяющими для работы металла при высоких температурах эксплуатации. Обоснованный выбор температуры эксплуатации, существенно повышающий релаксационную прочность зерен и межзеренных границ сплава, является основой продления ресурса работоспособности

The influence of weather-climatic and social factors on population mortality from circulatory diseases in Russia

Aim. To study the links between the standard mortality rate of the population from circulatory system diseases (CSD) with factors: weather-climatic (inter-day jumps in air temperature and atmospheric pressure by seasons and for the year) and social (average annual income per person and the number of doctors of all specialties) in Russia for the period 1995-2015. Materials and methods. According to station data and data of reanalysis, seasonal and annual amounts of day-to-day jumps in air temperature were calculated more than the absolute value of 4° and 6°C and the atmospheric pressure more than the absolute value of 8 GPa. The links between climate variables and the mortality rate of the population, taking into account social factors, were investigated using factor analysis, including regression and variance analyses. Results. Annual amounts of temperature (pressure) jumps of different signs vary greatly on the territory: the maximum amounts are 3-4 times higher than the minimum ones. The geographical distribution of air temperature fluctuations differs from the distribution of atmospheric pressure fluctuations. The sum of temperature jumps in the absolute value of more than 6°C is about twice less than the sum of jumps more than 4°C, but they are characterized by similarity of geographical distribution. The sum of the jumps of temperature (pressure) is reduced during the summer is approximately two times compared to the winter. The maximum jumps are observed mainly in the Northern regions with low population density, but with high per capita income, while the minimum is observed in the South-Western parts of the European part of the country with high population density, as well as middle and low income. Global warming does not significantly affect the reduction of annual amounts of temperature (pressure) jumps. Factor analysis of social and climatic variables in the territory for each year indicates the dominance of the influence of the social factor (per capita income) on the mortality rate from CSD. Conclusion. Factor analysis is integrated in the annual scale climatic and social variables showed a dominant effect on the coefficient of mortality from CSD, the factor of standard of living (per capita income of the population). Then the significance of the impact factors is consistently reduced: negative atmospheric pressure jumps, average seasonal pressure, health care level, positive pressure jumps. The significance of temperature variables is the smallest

The antioxidant system enzymes’ activity in rats’ brain, intoxicated with sodium fluoride in subtoxic doses

The aim of the study was to assess the activity of enzymes in the antioxidant system in the brain of rats subjected to intoxication with sodium fluoride in subtoxic doses. Methods. The studies were conducted on sexually mature Wistar rats weighing 180-220 g, subjected to oral exposure by means of a probe with aqueous solutions of sodium fluoride (SF) once daily for 60 days at doses of 1/10, 1/100 and 1/1000 DL50, correspondingly, equaling to 20 mg/kg, 2 mg/kg and 0.2 mg/kg of body weight. Chemoluminescent method was used to confirm the induction of free radical processes by measuring the intensity of super-weak luminescence in the homogenate of the liver and the brain in the range of 400-600 nm, which occurs as a result of chemoluminescent reactions. Statistical analysis of the results was carried out using Statistica 6.1 (StatSoft, Inc., USA). Results. Reducing the intensity of a superweak luminescence on the 60th day of oral administration of SF to rats at a dose of 1/10 DL50 indicates a depletion of the energy potential of the substrate and the inadequate admission of free radicals of biological molecules to the oxidation system. The results showed a significant (p<0.001) increase of chemoluminescence relative to the comparison group of animals in the induced by dual-valent iron ions in the brain of experimental group of rats, who were administered SF at a dose of 1/10 DL50 on the 10th day of observation, on average by 40%. Conclusion. Under conditions of long-term fluoride intoxication in the rat’s brain, the expressed disruptions of free radical oxidation occur, which is reflected as the increase in the intensity of chemoluminescence of its homogenate and decrease in the activity of the antioxidant enzymes, superoxide dismutase and catalase, in the neocortex, which is a significant factor in the depletion of the adaptive capacity of the body

ДИСТАНЦІЙНЕ НАВЧАННЯ ПРИ ВИКЛАДАННІ ПЕДІАТРИЧНИХ ДИСЦИПЛІН: ВИКЛИКИ ЧАСУ

The relevance of the chosen direction is due to the gowing role of distance learning technologies in the teaching of medical disciplines. The aim of the work is to assess the prospects for the use of distance learning technologies in the teaching of pediatric disciplines, including in conditions of quarantine restrictions. The study was conducted by bibliometric and content analysis of information sources obtained from electronic databases OVID, PubMed, Embase, as well as official sources of national ministries of education of developed countries and CIS countries. Search depth – 3 years. The obtained data are organized and analyzed with the selection of the main trends in the application and development of distance learning in the teaching of pediatric disciplines. In addition, a survey of 50 students of Odesa National Medical University and 20 teachers from departments that teach pediatric disciplines. Statistical processing was performed by analysis of variance using MS Excel software (Microsoft Inc., USA). In accordance with the order of the Ministry of Education and Science of Ukraine No. 406 of March 16, 2020 in medical universities of the country students switched to distance learning. For many teachers and students, this form of education has proved difficult. Along with purely technical problems (instability of the Internet connection, non compliance of equipment with software requirements, low level of computer literacy of elderly teachers) respondents noted the inconvenience of the interface, the difficulty of maintaining proper attention when working online, lack of practical skills. Among the main problems, teachers mentioned the difficulty of identifying users participating in the conference. In the conditions of quarantine restrictions application of remote technologies allows to carry out educational process at rather high level. Zoom and Microsoft Teams platforms are the most suitable for distance learning needs. Only half of the respondents were satisfied with the quality of distance learning during quarantine restrictions. This indicates a lack of preparation of both teachers and students for this format of the educational process.Актуальність обраного напрямку обумовлена зростанням ролі технологій дистанційного навчання у викладанні медичних дисциплін. Метою роботи є оцінка перспектив застосування технологій дистанційного навчання при викладанні педіатричних дисциплін, у тому числі в умовах карантинних обмежень. Дослідження проведене шляхом бібліометричного та контент-аналізу інформаційних джерел, одержаних з електронних баз даних OVID, PubMed, Embase, а також офіційних джерел національних міністерств освіти розвинутих країн світу та країн СНД. Глибина пошуку – 3 роки. Одержані дані упорядковані та проаналізовані із виділенням основних тенденцій у застосуванні та розвитку дистанційного навчання при викладанні педіатричних дисциплін. Додатково проведено анкетування 50 студентів Одеського національного медичного університету та 20 викладачів з кафедр, які викладають педіатричні дисципліни. Статистична обробка проведена методом дисперсійного аналізу з використанням програмного забезпечення MS Excel (Microsoft Inc., США). Відповідно до наказу МОН України від 16.03.2020 р. № 406, у медичних ВНЗ країни студенти перейшли на дистанційну форму навчання. Для багатьох викладачів та студентів така форма навчання виявилася складною. Поряд із суто технічними проблемами (нестійкість інтернет-з’єднання, невідповідність обладнання вимогам до програмного забезпечення, низький рівень комп’ютерної грамотності літніх викладачів) респонденти зазначали незручність інтерфейсу, складнощі підтримання належного рівня уваги при роботі он-лайн, недостатність набутття практичних навичок. Серед основних проблем викладачі називали складності ідентифікації користувачів, що беруть участь у конференції. В умовах карантинних обмежень застосування дистанційних технологій дозволяє проводити освітній процес на достатньо високому рівні. Найбільш придатними для потреб дистанційного навчання є платформи Zoom та Microsoft Teams. Лише половина респондентів була задоволена якістю дистанційного навчання під час карантинних обмежень. Це свідчить про недостатню підготовленість як викладачів, так і студентів до такого формату освітнього процесу

The experimental study of the pathogenic role of NADPH-oxidase in the thyroid gland tissues

The objective of the study was to compare the NADPH/ H2O2 system and the expression of enzymes in the culture of thyroid gland cells, depending on the sex. Material and methods. The thyroid gland was collected from adult female donors (n=20) and men (n=15). The cells were washed twice with HBSS and centrifuged at 1000 × g for 5 minutes, and then cultured to 106 cells in 0.5 ml culture medium per well in 24-well plates (Thermo Fisher Scientific, USA). H2O2 levels in the cells were determined quantitatively using a hydrogen peroxide sensor Premo™ Orp1-roGFP (Life Technologies, USA) according to manufacturer’s instructions. Statistical analysis of the results was carried out using Statistica 6.1 (StatSoft, Inc., USA). Results. We found that the expression of DUOX1 and NOX4 in the thyroid gland was significantly higher in women than in men (1.5 times, p<0.05). Expression of DUOX2 in female cells was 1.5 times higher than in men, but statistically significant (p=0.06). We have found that the thyroid gland of women produces a significantly higher H2O2 content than the male gland cells (p<0.05). The expression of DUOX1 and NOX4 is significantly higher in cells derived from the female thyroid gland than in cells derived from males. H2O2 levels were also higher in cells derived from female thyroid gland than in male cells. Conclusion. As a result of our experiment, the expression of DUOX1 and NOX4 is significantly higher in cells derived from the female thyroid gland than in cells derived from males. We have shown during the experiment that NOX4 is regulated both at the transcription level and at the level after transcription, and the level of sustained-release NOX4 mRNA does not accurately reflect the content and function of the NOX4 protein. Chronic effects on the female thyroid gland at higher concentrations of H2O2 can potentially cause many adverse effects