Evolutionary Status of Long-Period Radio Pulsars

We analyze the evolutionary status of recently discovered long-period radio sources PSR J0901-4046, GLEAM-X J1627-52, and GPM J1839-10. We discuss the hypothesis that all three sources are radio pulsars. In the framework of standard scenarios, it is often accepted that the pulsar mechanism is switched off when an external matter can penetrate the light cylinder. If the matter is stopped outside the light cylinder then the neutron star is at the ejector stage. We demonstrate that for realistic parameters of the interstellar medium, the 76-second pulsar PSR J0901-4046 might be at this stage. However, sources GLEAM-X J1627-52 and GPM J1839-10 with periods $\gtrsim 1000$ s can be ejectors only in the case of unrealistically large dipolar fields $\gtrsim 10^{16}$ G. Also, we show that neutron stars with spin periods $\sim 100$ s and dipolar magnetic fields $\lesssim 10^{13}$ G cannot be ejectors in a typical interstellar medium. Thus, we predict that long-period pulsars with standard fields will not be discovered.Comment: 7 pages, 2 figures, accepted to Astronomy Letters, translation by the author

Early Accretion Onset in Long-Period Isolated Pulsars

We model long-term magneto-rotational evolution of isolated neutron stars with long initial spin periods. This analysis is motivated by the recent discovery of young long-period neutron stars observed as periodic radio sources: PSR J0901-4046, GLEAM-X J1627-52, and GPM J1839-10. Our calculations demonstrate that for realistically rapid spin-down during the propeller stage all isolated neutron stars with velocities $\lesssim100$ km s$^{-1}$ are able to reach the stage of accretion from the interstellar medium within a few billion years. If neutron stars with long initial spin periods form a relatively large fraction of all Galactic neutron stars then the number of isolated accretors is sufficiently larger than it has been predicted by previous studies.Comment: 12 pages, 2 figures, submitted to PAS

The Riemann problem for functions with polar lines of higher orders

© 2014, Allerton Press, Inc. We consider solutions of the jump problem, homogeneous and inhomogeneous Riemann problems for functions with polar lines of orders pk +1 (k = 1, 2, … ), pk ⩾ 0. We study the cases of continuous and discontinuous coefficients. In the special case pk = 0 the obtained results turn into the earlier known ones

Asymptotics of conditional probabilities of succesful allocation of random number of particles into cells

© 2017 Walter de Gruyter GmbH, Berlin/Boston 2017. The article is devoted to the memory of Valentin Fedorovich Kolchin. Let ζ, ζ i (i N) be independent identically distributed nonnegative integer-valued random variables, (η i1 ,.., η iN ) be the fillings of cells in the generalized scheme of allocation of ζ i particles into N cells, 1 ≤ i ≤ n, for fixed Z n = (ζ 1 , .., ζ n ) these allocation schemes are independent. We consider the conditional probabilities P(A n,N | Z n ) of the event A n,N = {each cell in each of n allocation schemes contains no more than r particles}, where r is some fixed number. The sufficient conditions for the convergence of the sequence P(A n,N | Z n ) to a nonrandom limit with probability 1 are given. It is shown that the random variable ln P(A n,N | Z n ) is asymptotically normal. Applications of the obtained results to the noise-proof encoding are discussed

Technologies for Adaptation Of Youth in Innovative Activities

В условиях необходимости обеспечения технологического суверенитета обоснована перспектива развития творческой активности молодежи. Эксплицированы практики реализации акционистской программы исследования, реализованной в ходе подготовки и проведения мастер-класса. Обсуждаются риски и сильные стороны мастер-класса как инструмента стимулирования инновационной активности молодежи.The prospect is substantiated, in the conditions of the need to ensure technological sovereignty, the development of the creative activity of young people. The practices of implementing the actionist research program implemented during the preparation and conduct of the master class are explicated. The risks and strengths of the master class as a tool to stimulate the innovative activity of young people are discussed

Planktonic Communities in the Torey Lakes (Zabaikalsky Krai) in a Low Water Year

Lakes Barun-Torey and Zun-Torey are the largest water bodies in Zabaikalsky Krai, and they are characterized by long-term cyclic changes in the water level. Samples of the planktonic community (algae and invertebrates) were collected from the Torey Lakes in June, August, and October in the dry 2016. Collection and processing of the samples was carried out using standard hydrobiological methods. The aim of the study was to investigate the planktonic communities in the Torey Lakes. The lakes were in different hydrological phases: Barun-Torey was in the initial filling phase (with isolated small lakes present on the dried bed), and Zun-Torey was in the shallowing phase. Considerable differences were observed between the compositions and structures of the planktonic communities, which were determined by the mineral content of the water. Diverse littoral plankton developed, consisting of 2-25 taxa of algae (total number of taxa – 46) and 2-15 species of invertebrates (total number of species – 29) in the oligohaline small lakes on the bottom of Lake Barun-Torey. The abundance and biomass of aquatic organisms varied within very wide limits: for phytoplankton – from 0.7 × 103 to 1260.0 × 103 cells / L and from 0.1 to 1271.0 mg / m3, and for zooplankton – from 9.2 × 103 to 19370.0 × 103 individuals / m3 and from 3.8 to 361.7 g / m3. Freshwater and euryhaline species were dominant. In polyhaline Lake Zun-Torey, the phytoplankton consisted of 3-12 taxa of algae (total number of taxa – 18), and the invertebrate fauna included only 3 species. The abundance of phytoplankton varied from 12.4 × 103 to 310.7 × 103 cells / L and a biomass from 1.0 to 14.7 mg / m3, and the abundance of zooplankton varied from 55.1 × 103 to 1656.0 × 103 individuals / m3 and a biomass from 1.1 to 85.5 g / m3. Euryhaline and halophilic species dominate

DIAGNOSTIC DIFFICULTIES OF THE ISOLATED LIVER TUBERCULOSIS

The article describes the case of abdominal tuberculosis – isolated tuberculous lesion of liver. The diagnosis was based on computer tomography of the abdomen and retroperitoneal space with bolus amplification, histological testing of surgery specimens and positive results of diaskintest. This case proves the difficulties of abdominal tuberculosis diagnostics and it justifies the need to perform magnetic resonance tomography of the abdomen, and computer tomography of the abdomen with bolus amplification, special attention is to be paid to the patients with low-grade fever belonging to tuberculosis risk groups

Discriminability of tryptophan containing dipeptides using quantum control

We show that the coherent manipulation of molecular wavepackets in the excited states of trp-containing dipeptides allows efficient discrimination among them. Optimal dynamic discrimination fails, however, for some dipeptide couples. When considering the limited spectral resources at play (3nm bandwidth at 266nm), we discuss the concept of discriminability, which appears uncorrelated to both static spectra and relaxation lifetime

Analyzing the Influence of Diatomite and Mineral Fertilizers on the Features of Cadmium-Contaminated Urban Lawns

Contamination with heavy metals is among key anthropogenic pressures, experienced by urban lawns. It results in depletion of their environmental quality and functions. Implementation of fertilizers, containing silicon, is a promising approach to increase urban lawns’ sustainability to heavy metals’ pollution. Based on the field experiment, an influence of cadmium contamination on the chemical features and biomass quality of modeled urban green lawn ecosystems was studied. We demonstrated an increase of cadmium consumption by biomass on the second year of observations as the result of diatomite implementation together with mineral fertilizers. Both total sugar and disaccharides’ content in biomass was 15-20% higher for the contaminated plots where diatomite was implemented together with mineral fertilizers, compared to the uncontaminated control. This evidences a positive effect of the implemented reclaiming on stress tolerance of the green lawns

Structural study of the type II 3-dehydroquinate dehydratase from Actinobacillus pleuropneumoniae

9 pages, 7 figures, 2 tables.The structure of the type II dehydroquinate dehydratase (DHQase) from Actinobacillus pleuropneumoniae, the third enzyme of the shikimate pathway, has been determined. Crystals diffracting to 1.7 Å were obtained in space and on earth using the counter-diffusion technique. The structure was solved using molecular replacement and refined to high resolution. The overall structure of the dodecameric enzyme is described and compared with structures of DHQases from other bacteria. DHQases contain a flexible loop that presumably closes over the active site upon substrate binding. The enzyme can exist in an open or closed conformation. The present structure displays the open conformation, with a sulfate anion bound in the active site. The availability of this structure opens a route to structure-based antibiotics targetting this pathogenic bacterium.We thank Professor Kabsch for providing XDS free of charge. We acknowledge the support of the European Space Agency and the European Community Action to Research Infrastructure Action of the Improving Human Potential Programme to the EMBL Hamburg Outstation, contract No. HPRI-CT-1999-00017. We thank Olivier Minster (ESA) for his support of space science. The authors acknowledge the excellent work of Dr Eva ManÄ as in managing the logistics concerning the space mission. We thank Viscount Dirk Frimout for his support for space crystallization experiments.Peer reviewe