Painleve IV and degenerate Gaussian Unitary Ensembles

We consider those Gaussian Unitary Ensembles where the eigenvalues have prescribed multiplicities, and obtain joint probability density for the eigenvalues. In the simplest case where there is only one multiple eigenvalue t, this leads to orthogonal polynomials with the Hermite weight perturbed by a factor that has a multiple zero at t. We show through a pair of ladder operators, that the diagonal recurrence coefficients satisfy a particular Painleve IV equation for any real multiplicity. If the multiplicity is even they are expressed in terms of the generalized Hermite polynomials, with t as the independent variable.Comment: 17 page

Adsorption and two-body recombination of atomic hydrogen on 3^3He-4^4He mixture films

We present the first systematic measurement of the binding energy $E_a$ of hydrogen atoms to the surface of saturated $^3$He-$^4$He mixture films. $E_a$ is found to decrease almost linearly from 1.14(1) K down to 0.39(1) K, when the population of the ground surface state of $^3$He grows from zero to $6\times10^{14}$ cm$^{-2}$, yielding the value $1.2(1)\times 10^{-15}$ K cm$^2$ for the mean-field parameter of H-$^3$He interaction in 2D. The experiments were carried out with overall $^3$He concentrations ranging from 0.1 ppm to 5 % as well as with commercial and isotopically purified $^4$He at temperatures 70...400 mK. Measuring by ESR the rate constants $K_{aa}$ and $K_{ab}$ for second-order recombination of hydrogen atoms in hyperfine states $a$ and $b$ we find the ratio $K_{ab}/K_{aa}$ to be independent of the $^3$He content and to grow with temperature.Comment: 4 pages, 4 figures, all zipped in a sigle file. Submitted to Phys. Rev. Let

О РОЛИ ОТЕЧЕСТВЕННОЙ НАУКИ В РАЗВИТИИ АТОМНОЙ ЭНЕРГЕТИКИ В РЕСПУБЛИКЕ БЕЛАРУСЬ

The history of the development of nuclear science researches in the nuclear center of the Republic of Belarus is described. There were two State programs in Belarus devoted to the problems of the nuclear power. One of them was finished in 2010. Within the program, there have been resolved such tasks as: necessity of the nuclear power engineering, selection of the site for the nuclear power plant, developments of the legislation and regulations to ensure nuclear and radiation safety, as well as project of the strategy for radioactive waste management and spent fuel management. At the second stage for fulfilling the tasks of development and implementation of scientific and technical suggestions, the State program «Scientific support of nuclear power development in the Republic of Belarus for 2009–2010 and for the period till 2020» is carried out. The results of researches within the second program for 2013–2015 years are presented.В статье дается краткий обзор научной деятельности в области атомной энергетики в советский и постсоветский периоды развития Республики Беларусь. Приводятся сведения о производстве и потреблении электроэнергии, которые свидетельствуют о целесообразности развития атомной энергетики в Республике Беларусь. Описываются этапы развития работ в этой области. Первый этап включает обоснование необходимости строительства АЭС, ее мощности, определение места размещения, выбор площадки АЭС, разработку нормативной правовой и нормативной технической базы и проекта стратегии обращения с радиоактивными отходами и отработавшим ядерным топливом в Республике Беларусь. Указанные задачи решались в 2006–2010 гг. в рамках Государственной научно-технической программы «Ядерно-физические технологии для народного хозяйства Беларуси». На втором этапе с целью разработки и внедрения научно-технических предложений об оптимизации технологических процессов, повышающих ядерную, радиационную и экологическую безопасность, физическую защиту, а также эффективность объектов использования атомной энергии, была утверждена Государственная программа «Научное сопровождение развития атомной энергетики в Республике Беларусь на 2009–2010 годы и на период до 2020 года». Поскольку результаты выполнения заданий этой программы за 2009–2012 гг. были опубликованы ранее, в статье приводятся результаты исследований за 2013–2015 гг.

РАДОН В ВОЗДУХЕ ЗДАНИЙ НАСЕЛЕННЫХ ПУНКТОВ ВИТЕБСКОЙ ОБЛАСТИ

Radon from natural and anthropogenic radiation sources contributes significantly to the public exposure. For that reason, systematic radon monitoring is carried out in Belarus. The main source of radon in the air of premises is its emanation from the geological space under the buildings. The results of radon monitoring in 665 premises in 21 settlements of Vitebsk region are presented. The parameters investigated were: radon volumetric activity in the air of home accommodations and industrial premises (ОАRn), radon equivalent equilibrium volumetric activity and annual effective dose of public exposure due to radon-222 and its progenies (ERn). The excess values of radon volumetric activity in relation to the statutory criteria (200 Bq/m3 ) have been detected for 18 premises (2.7 %). Among them 16 are living accommodation and 2 are industrial premises. The weighted average annual effective dose of public exposure due to radon and its progenies in Vitebsk region is 4.5 mSv per year. Its value for Polatsk district is 2 mSv per year and 7.6 mSv per year – for Glubokae district. Maximum of the weighted average annual effective dose is reported for Garadok dictrict and it makes 32.4 mSv per year. The population exposure to radon and its progenies is the main dose forming factor in comparison with other natural and anthropogenic radiation sources, including exposure from Chernobyl radionuclides.Проведение систематических радонометрических исследований на территории Беларуси обусловлено значительным вкладом радона в облучение населения от природных и техногенных источников ионизирующего излучения. При этом основным источником поступления радона в воздух зданий является геологическое пространство под зданиями. Представлены данные, полученные при проведении мониторинга на территории 21 административного района Витебской области: объемная активность радона в воздухе жилых и административных зданий (ОАRn), эквивалентная равновесная объемная активность радона и годовая эффективная доза облучения населения (ERn), обусловленная радоном и дочерними продуктами его распада (ДПР). Общее количество обследованных помещений составило 665. Превышение нормируемого законодательством Республики Беларусь значения ЭРОАRn (200 Бк/м3 ) наблюдалось в 18 помещениях (2,7%), среди которых 16 – жилые дома, 2 – административные здания. Средневзвешенная годовая эффективная доза облучения населения Витебской области, обусловленная радоном и его ДПР, составляет 4,5 мЗв/год, при вариации в отдельных районах от 2 (Полоцкий район) до 7,6 мЗв/год (Глубокский район). Наибольшее значение ЕRn, равное 32,4 мЗв/год, наблюдается в административном помещении Городокского района. Показано, что облучение населения Витебской области радоном и его ДПР является основным дозообразующим фактором по сравнению со всеми остальными компонентами природного и техногенного радиоактивных излучений, включая облучение от чернобыльских радионуклидов.

Brucellosis: Trends in the Development of Situation in the World and Forecast for 2022 in the Russian Federation

An analysis of trends in the development of situation on brucellosis in the world over past decade and the data on the main risk factors for the occurrence of epidemiological complications regarding this infection in various regions of the world are provided in the paper. An expert assessment of the current epizootiological and epidemiological situation on brucellosis, the coverage of population and animals with immunization in the Russian Federation is given. Over 9 months of 2021, 210 potentially hazardous as regards brucellosis in cattle areas and 24 sites – as regards brucellosis in small ruminants – were registered in Russia. Compared to the same period in 2020, there was a decrease in the number of newly identified hazardous sites for bovine brucellosis by 35.8 % (117 areas). However, long-term upward trend in epizootiological adversity for bovine brucellosis in Russia persists. The epidemiological situation on brucellosis in the country for the period of 2012–2021 is characterized as unfavorable. Decrease in the number of newly detected human brucellosis cases (by 25.1 % of long-term average values) is observed against the background of persistent unfavorable epizootic conditions for brucellosis among epidemiologically significant species of small ruminants and cattle in regions with developed animal husbandry. In 2021, clusters of human cases were registered in the Republic of Dagestan and Penza Region. In the Republic of Dagestan, against the background of aggravation of epizootiological and epidemiological situation on brucellosis, there was also an alarming trend towards prevalence of a relatively high incidence among minors. The proportion of cases of brucellosis among children under the age of 17 in the Republic amounted to 60.3 % of the total number of minors with newly diagnosed brucellosis in Russia over the past 10 years. Taking into account current epizootic, epidemic situations and the long-term dynamics of the development of situation on  brucellosis in the Russian Federation, the incidence of brucellosis among the population  is predicted to be 10–15 % lower than the average long-term values – 0.18–0.20 per 100000 of the population – in 2022. The number of human cases of brucellosis can range from 250 to 300

Tacaribe Virus but Not Junin Virus Infection Induces Cytokine Release from Primary Human Monocytes and Macrophages

The mechanisms underlying the development of disease during arenavirus infection are poorly understood. However, common to all hemorrhagic fever diseases is the involvement of macrophages as primary target cells, suggesting that the immune response in these cells may be of paramount importance during infection. Thus, in order to identify features of the immune response that contribute to arenavirus pathogenesis, we have examined the growth kinetics and cytokine profiles of two closely related New World arenaviruses, the apathogenic Tacaribe virus (TCRV) and the hemorrhagic fever-causing Junin virus (JUNV), in primary human monocytes and macrophages. Both viruses grew robustly in VeroE6 cells; however, TCRV titres were decreased by approximately 10 fold compared to JUNV in both monocytes and macrophages. Infection of both monocytes and macrophages with TCRV also resulted in the release of high levels of IL-6, IL-10 and TNF-α, while levels of IFN-α, IFN-β and IL-12 were not affected. However, we could show that the presence of these cytokines had no direct effect on growth of either TCRV of JUNV in macrophages. Further analysis also showed that while the production of IL-6 and IL-10 are dependent on viral replication, production of TNF-α also occurs after exposure to UV-inactivated TCRV particles and is thus independent of productive virus infection. Surprisingly, JUNV infection did not have an effect on any of the cytokines examined indicating that, in contrast to other viral hemorrhagic fever viruses, macrophage-derived cytokine production is unlikely to play an active role in contributing to the cytokine dysregulation observed in JUNV infected patients. Rather, these results suggest that an early, controlled immune response by infected macrophages may be critical for the successful control of infection of apathogenic viruses and prevention of subsequent disease, including systemic cytokine dysregulation

Концентрация радона в воздухе помещений Витебской, Могилевской и Гомельской областей Беларуси и оценка дозы облучения населения радоном

The summarized data on indoor radon concentrations and estimated effective radon doses in the Vitebsk, Mogilev and Gomel regions of Belarus are presented. The passive track detector method was used to carry out the indoor radon monitoring. The measurement results are summarized in the geoinformation database. The map of the annual radon equivalent equilibrium concentrations distribution in administrative districts was created. The analysis of the results revealed that in 2.3, 1.3 and 0.4 % of dwelling of the Vitebsk, Mogilev and Gomel region correspondingly, the indoor radon equivalent equilibrium concentration exceeded the regulatory established limit of 200 Bq/m3. For effective planning of further radon monitoring, maps of absolute and relative number of measurements per administrative district were built. The calculated effective radon doses for the population and comparison to those from the “Chernobyl” radionuclides showed that radon is the main contributor to the public exposure.В работе представлены систематизированные данные о концентрации радона в воздухе помещений на территории Витебской, Могилевской и Гомельской областей Беларуси и проведена оценка вклада радона в годовую эффективную дозу облучения населения данных областей. Исследования проводились с использованием интегрального метода пассивной трековой радиометрии c применением твердотельных трековых детекторов альфа-частиц. По результатам измерений объемной активности радона актуализирована геоинформационная база данных и построена карта распределения значений среднегодовой эквивалентной равновесной объемной активности радона в воздухе помещений на территории Витебской, Могилевской и Гомельской областей. Анализ полученных результатов выявил 2,3, 1,3 и 0,4 % зданий соответственно в Витебской, Могилевской и Гомельской областях, в которых превышен нормируемый в Республике Беларусь уровень среднегодовой эквивалентной равновесной объемной активности радона в 200 Бк/м3. Для эффективного планирования дальнейших исследований построены карты распределения количества измерений по административным районам исследуемых областей. Анализ значений средних эффективных доз облучения населения «чернобыльскими» радионуклидами и радоном показал, что основной вклад в облучение населения Витебской, Могилевской и Гомельской областей вносит радон

About the first experiment at JINR nuclotron deuteron beam with energy 2.52 gev on investigation of transmutation of I-129, NP-237, PU-238 and PU-239 in the field of neutrons generated in pbtarget with U-blanket

The experiment described in this communication is a part of the scientific program „Investigations of physical aspects of electronuclear method of energy production and transmutation of radioactive waste of atomic energetic using relativistic beams from the JINR Synchrophasotron/Nuclotron“ - the project „Energy plus Transmutation“. The performing of the first experiment at deuteron beam with energy 2.52 GeV at the electronuclear setup which consists of Pb-target with U-blanket (206.4 kg of natural uranium) and transmutation samples and its preliminary results are described. The hermetic samples of isotopes of I-129, Np-237, Pu-238 and Pu-239 which are produced in atomic reactors and industry setups which use nuclear materials and nuclear technologies were irradiated in the field of electronuclear neutrons produced in the Pbtarget surrounded with the U-blanket setup “Energy plus transmutation”. The estimations of its transmutations (radioecological aspect) were obtained in result of measurements of gamma activities of these samples. The information about space-energy distribution of neutrons in the volume of the Pb-target and the U-blanket was obtained with help of sets of activation threshold detectors (Al, V, Cu, Co, Y, In, I, Ta, Au, W, Bi and other), solid state nuclear track detectors, He-3 neutron detectors and nuclear emulsions

The N-Terminal Domain of the Arenavirus L Protein Is an RNA Endonuclease Essential in mRNA Transcription

Arenaviridae synthesize viral mRNAs using short capped primers presumably acquired from cellular transcripts by a ‘cap-snatching’ mechanism. Here, we report the crystal structure and functional characterization of the N-terminal 196 residues (NL1) of the L protein from the prototypic arenavirus: lymphocytic choriomeningitis virus. The NL1 domain is able to bind and cleave RNA. The 2.13 Å resolution crystal structure of NL1 reveals a type II endonuclease α/β architecture similar to the N-terminal end of the influenza virus PA protein. Superimposition of both structures, mutagenesis and reverse genetics studies reveal a unique spatial arrangement of key active site residues related to the PD…(D/E)XK type II endonuclease signature sequence. We show that this endonuclease domain is conserved and active across the virus families Arenaviridae, Bunyaviridae and Orthomyxoviridae and propose that the arenavirus NL1 domain is the Arenaviridae cap-snatching endonuclease

The Impact of Human Conflict on the Genetics of Mastomys natalensis and Lassa Virus in West Africa

Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago). Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease