One- and two-photon resonant spectroscopy of hydrogen and anti-hydrogen atoms in external electric fields

The resonant spectra of hydrogen and anti-hydrogen atoms in the presence of an external electric field are compared theoretically. It is shown that nonresonant corrections to the transition frequency contain terms linear in the electric field. The existence of these terms does not violate space and time parity and leads to a difference in the resonant spectroscopic measurements for hydrogen and anti-hydrogen atoms in an external electric field. The one-photon 1s-2p and the two-photon 1s-2s resonances are investigated

Analytical solution of second Stokes problem of behaviour of rarefied gas with Cercignani boundary accomodation conditions

Analytical solution of second Stokes problem of behaviour of rarefied gas with Cercignani boundary accomodation conditions The second Stokes problem about behaviour of rarefied gas filling half-space is analytically solved. A plane, limiting half-space, makes harmonious fluctuations in the plane. The kinetic BGK-equation (Bhatnagar, Gross, Krook) is used. The boundary accomodation conditions of Cercignani of reflexion gaseous molecules from a wall are considered. Distribution function of the gaseous molecules is constructed. The velocity of gas in half-space is found, also its value direct at a wall is found. The force resistance operating from gas on border is found. Besides, the capacity of dissipation of the energy falling to unit of area of the fluctuating plate limiting gas is obtained.Comment: 26 pages, 5 figure

Aerothermodynamic Analysis of a Reentry Brazilian Satellite

This work deals with a computational investigation on the small ballistic reentry Brazilian vehicle SARA (acronyms for SAt\'elite de Reentrada Atmosf\'erica). Hypersonic flows over the vehicle SARA at zero-degree angle of attack in a chemical equilibrium and thermal non-equilibrium are modeled by the Direct Simulation Monte Carlo (DSMC) method, which has become the main technique for studying complex multidimensional rarefied flows, and that properly accounts for the non-equilibrium aspects of the flows. The emphasis of this paper is to examine the behavior of the primary properties during the high altitude portion of SARA reentry. In this way, velocity, density, pressure and temperature field are investigated for altitudes of 100, 95, 90, 85 and 80 km. In addition, comparisons based on geometry are made between axisymmetric and planar two-dimensional configurations. Some significant differences between these configurations were noted on the flowfield structure in the reentry trajectory. The analysis showed that the flow disturbances have different influence on velocity, density, pressure and temperature along the stagnation streamline ahead of the capsule nose. It was found that the stagnation region is a thermally stressed zone. It was also found that the stagnation region is a zone of strong compression, high wall pressure. Wall pressure distributions are compared with those of available experimental data and good agreement is found along the spherical nose for the altitude range investigated.Comment: The paper will be published in Vol. 42 of the Brazilian Journal of Physic

Quantum Drag Forces on a Sphere Moving Through a Rarefied Gas

As an application of quantum fluid mechanics, we consider the drag force exerted on a sphere by an ultra-dilute gas. Quantum mechanical diffraction scattering theory enters in that regime wherein the mean free path of a molecule in the gas is large compared with the sphere radius. The drag force is computed in a model specified by the ``sticking fraction'' of events in which a gaseous molecule is adsorbed by the spherical surface. Classical inelastic scattering theory is shown to be inadequate for physically reasonable sticking fraction values. The quantum mechanical scattering drag force is exhibited theoretically and compared with experimental data.Comment: 5 pages no figure

Эпидемиология внелегочного туберкулеза в регионах с высокой заболеваемостью

The objective of the study: to assess the structure of extrapulmonary tuberculosis in two high-burden regions (Siberia, the Far East of the Russian Federation, and the Republic of Tajikistan), with the consideration of HIV status, gender, and age of patients. Subjects and methods. A simple cohort open retrospective study was carried out based on the analysis of statistical reports from TB control institutions of the Republic of Tajikistan, Siberian and Far Eastern Federal Districts of the Russian Federation for 2018. Results. In the Siberian Federal District and Far Eastern Federal District, among extrapulmonary forms of tuberculosis, the proportion of bone and joint tuberculosis made 43.6%, urinary tuberculosis – 21.3%, and tuberculosis of central nervous system ranked third and made 17%. In Tajikistan, bone and joint tuberculosis also prevailed and made 46.0%, followed by tuberculosis of peripheral lymph nodes. In Tajikistan, among extrapulmonary tuberculosis patients, HIV positive patients made only 3.5%, while in the Siberian and Far Eastern Federal Districts, they made 36.8%. However, in the Siberian and Far Eastern Federal Districts of the Russian Federation, among HIV positive patients with extrapulmonary tuberculosis, tuberculosis of the central nervous system (38.3%) prevailed, in the Republic of Tajikistan it was tuberculosis of peripheral lymph nodes (37.9%), followed by bone and joint tuberculosis (31.0%) and abdominal tuberculosis (17.2%). Urogenital tuberculosis was in the last place in the structure of extrapulmonary tuberculosis in HIV-positive patients.Цель исследования: оценить структуру внелегочного туберкулеза (ВТЛ) в двух эпидемически неблагополучных регионах (Сибирь, Дальний Восток РФ и Республика Таджикистан) с учетом ВИЧ-статуса, пола и возраста пациентов. Материал и методы. Простое когортное открытое ретроспективное исследование проведено на основе анализа статистических отчетов противотуберкулезных учреждений Республики Таджикистан, Сибирского (СФО) и Дальневосточного (ДФО) федерального округа РФ за 2018 г. Результаты. В СФО и ДФО РФ в структуре ВЛТ доля костно-суставного туберкулеза (КСТ) составила 43,6%, мочеполового – 21,3%, на третьем месте – туберкулез центральной нервной системы (ЦНС) – 17%. В Таджикистане ведущей локализацией также был КСТ ‒ 46,0%, на втором месте ‒ туберкулез периферических лимфатических узлов (ТПЛУ). В Таджикистане среди больных ВЛТ было всего 3,5% ВИЧ-позитивных, а в СФО и ДФО РФ ‒ 36,8%. При этом если в СФО и ДФО РФ среди больных с ВЛТ при ВИЧ-позитивном статусе преобладал туберкулез ЦНС (38,3%), то в Республике Таджикистан это был ТПЛУ (37,9%), затем КСТ (31,0%) и абдоминальный туберкулез (17,2%). Урогенитальный туберкулез был на последнем месте в структуре ВЛТ при ВИЧ-позитивном статусе

Authoritative subspecies diagnosis tool for European honey bees based on ancestryinformative SNPs

Background With numerous endemic subspecies representing four of its five evolutionary lineages, Europe holds a large fraction of Apis mellifera genetic diversity. This diversity and the natural distribution range have been altered by anthropogenic factors. The conservation of this natural heritage relies on the availability of accurate tools for subspecies diagnosis. Based on pool-sequence data from 2145 worker bees representing 22 populations sampled across Europe, we employed two highly discriminative approaches (PCA and F-ST) to select the most informative SNPs for ancestry inference. Results Using a supervised machine learning (ML) approach and a set of 3896 genotyped individuals, we could show that the 4094 selected single nucleotide polymorphisms (SNPs) provide an accurate prediction of ancestry inference in European honey bees. The best ML model was Linear Support Vector Classifier (Linear SVC) which correctly assigned most individuals to one of the 14 subspecies or different genetic origins with a mean accuracy of 96.2% +/- 0.8 SD. A total of 3.8% of test individuals were misclassified, most probably due to limited differentiation between the subspecies caused by close geographical proximity, or human interference of genetic integrity of reference subspecies, or a combination thereof. Conclusions The diagnostic tool presented here will contribute to a sustainable conservation and support breeding activities in order to preserve the genetic heritage of European honey bees.The SmartBees project was funded by the European Commission under its FP7 KBBE programme (2013.1.3-02, SmartBees Grant Agreement number 613960) https://ec.europa.eu/research/fp7.MP was supported by a Basque Government grant (IT1233-19). The funders provided the financial support to the research, but had no role in the design of the study, analysis, interpretations of data and in writing the manuscript

Motion of a rarefied gas in a plane channel in the presence of condensation on the channel walls

We examine the flow of a rarefied gas through a broad range of Knudsen numbers under the action of small pressure and temperature differences in a plane short channel, with provision made for the processes of evaporation and condensation at the channel walls. © 1990 Plenum Publishing Corporation

Epidemiology of extrapulmonary tuberculosis in high-burden regions

The objective of the study: to assess the structure of extrapulmonary tuberculosis in two high-burden regions (Siberia, the Far East of the Russian Federation, and the Republic of Tajikistan), with the consideration of HIV status, gender, and age of patients. Subjects and methods. A simple cohort open retrospective study was carried out based on the analysis of statistical reports from TB control institutions of the Republic of Tajikistan, Siberian and Far Eastern Federal Districts of the Russian Federation for 2018. Results. In the Siberian Federal District and Far Eastern Federal District, among extrapulmonary forms of tuberculosis, the proportion of bone and joint tuberculosis made 43.6%, urinary tuberculosis – 21.3%, and tuberculosis of central nervous system ranked third and made 17%. In Tajikistan, bone and joint tuberculosis also prevailed and made 46.0%, followed by tuberculosis of peripheral lymph nodes. In Tajikistan, among extrapulmonary tuberculosis patients, HIV positive patients made only 3.5%, while in the Siberian and Far Eastern Federal Districts, they made 36.8%. However, in the Siberian and Far Eastern Federal Districts of the Russian Federation, among HIV positive patients with extrapulmonary tuberculosis, tuberculosis of the central nervous system (38.3%) prevailed, in the Republic of Tajikistan it was tuberculosis of peripheral lymph nodes (37.9%), followed by bone and joint tuberculosis (31.0%) and abdominal tuberculosis (17.2%). Urogenital tuberculosis was in the last place in the structure of extrapulmonary tuberculosis in HIV-positive patients