| 1. |
- Mikhailov, V. V., et al.
(author)
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Trapped Positrons and Electrons in the Inner Radiation Belt According to Data of the PAMELA Experiment
- 2018
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In: Physics of Atomic Nuclei. - : PLEIADES PUBLISHING INC. - 1063-7788 .- 1562-692X. ; 81:4, s. 515-519
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Journal article (peer-reviewed)abstract
- Measurements of secondary-electron and secondary-positron fluxes below the geomagnetic cutoff in near-Earth space were performed by means of the PAMELA magnetic spectrometer installed on board the Resurs-DK1 satellite launched on June 15, 2006, in an elliptical orbit of inclination 70A degrees and altitude 350 to 600 km. This spectrometer permits measuring the fluxes of electrons and positrons over a wide energy range, as well as determining their spatial distributions to a precision of about 2A degrees. A calculation of particle trajectories in the geomagnetic field makes it possible to separate electrons and positrons originating from cosmic-ray interactions in the Earth's magnetosphere. The spatial distributions of quasitrapped, trapped, and short-lived albedo positrons and electrons of energy above 70 MeV in the radiation belt were analyzed. The ratio of the electron-to-positron fluxes and the energy spectra of the electrons and positrons in question are indicative of different productionmechanisms for stably trapped and quasitrapped secondary particles.
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| 2. |
- Mikhailov, V., et al.
(author)
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Measurements of electron and positron fluxes below the geomagnetic cutoff by the PAMELA magnetic spectrometer
- 2017
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In: Proceedings of Science. - : Sissa Medialab Srl.
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Conference paper (peer-reviewed)abstract
- We present a measurements of electron and positron fluxes below the geomagnetic cutoff rigidity in wide energy range from 50 MeV to several GeVs by the PAMELA magnetic spectrometer. The instrument was launched on June 15th 2006 on-board the Resurs-DK satellite on low orbit with 70 degrees inclination and altitude between 350 and 600 km. Features of spatial distributions of secondary electrons and positrons in the near Earth space, including the South Atlantic Anomaly, were investigated in terms of lifetime and geographical origin. The separation in stably trapped, long lifetime quasi-trapped, and short lifetime albedo components was performed on base of back tracing procedure in geomagnetic field. A significant difference in relative abundance of positrons with respect to electrons is seen for the stable trapped and the quasi-trapped populations what pointing out on differences in trapping mechanism of those populations.
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| 3. |
- Maltseva, Arina L., et al.
(author)
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Phylogeography of the closely related Littorina (Neritrema) species in the North-East Atlantic
- 2022
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In: Invertebrate Zoology. - : KMK Scientific Press. - 1812-9250 .- 1814-0815. ; 19:4, s. 404-424
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Journal article (peer-reviewed)abstract
- Phylogeographic studies of evolutionary young species co-existing over a vast geographic area can provide insights in the process of evolutionary divergence and its cohesiveness in different parts of the species ranges. The Littorina snails of the ‘saxatilis’ cryptic group diverged in near-glacial time, and tend to live in sympatry. L. saxatilis is widely distributed on both sides of the North Atlantic, while L. arcana and L. compressa are patchy distributed on the shores of Europe and Atlantic islands. The biogeographic history of the Littorina ‘saxatilis’ cryptic group is still obscure, with L. saxatilis studied much better than the other two species. We evaluated the population structure of the three ‘saxatilis’ species on the coasts of Wales, the Norwegian and the Barents seas using several genetic markers: the mitochondrial cytochrome b gene (cytb, partial, 26 haplotypes for 268 sequences), nuclear (5 microsatellite loci in 458 individuals) and whole-genome (2bRAD, 63 417 loci in 114 individuals) markers. Analyses based on the cytb and microsatellite markers showed a deep divergence between the British and the North European populations of all three species with a high genetic similarity between their sympatric populations from Wales. L. compressa had the highest differentiation from both L. arcana and L. saxatilis and demonstrated the clear population structure due to allele frequency. The degree of the genetic differentiation between sympatric L. arcana and L. saxatilis in some regions was lower than between the regions within a species. Moreover, analyses of all three types of used markers indicate that the continental populations of L. arcana include individuals with contrasting genomic profiles. Our results suggest that L. arcana and L. compressa separated from their common ancestor L. islandica after L. saxatilis. The three sibling species survived glaciation in a refugium (or refugia) on the British coasts, separated from the mainland refugium (or refugia). After the glaciation, L. compressa colonised the mainland, most likely from a single European refugium. Post-glacial continental repopulation by L. arcana could have occurred from at least two sources, with two differentiated lineages still recognisable. Further inclusion of Littorina populations from South Norway and France is needed to complete the reconstruction of biogeographic history in these three evolutionary young species of Littorina snails.
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| 4. |
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| 5. |
- Elming, Sten-åke, et al.
(author)
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Palaeomagnetism and AR-40/AR-39 age determinations of the Ediacaran traps from the southwestern margin of the East European Craton, Ukraine : relevance to the Rodinia break-up
- 2007
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In: Journal of the Geological Society. - : Geological Society of London. - 0016-7649 .- 2041-479X. ; 164:5, s. 969-982
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Journal article (peer-reviewed)abstract
- A palaeomagnetic study and age determinations have been performed on Ediacaran basalts from the northwestern Ukraine. Whole-rock ^sup 40^Ar/^sup 39^Ar age determination revealed plateau ages at 590-560 Ma and 393 Ma, the latter probably reflecting a resetting of the radiometric system. Palaeomagnetic poles have been calculated from five basalt flows, two of which (A poles) are considered reliable with ages that range from 580 to 560 Ma. Tentative poles (B poles), calculated from most probably primary magnetizations, have ages estimated at 580-545 Ma. Secondary magnetizations, possibly of late Ediacaran or Devonian age, have also been isolated (C poles). Based on the new poles, Baltica drifted together with Laurentia from an equatorial position at c. 750 Ma to occupy high southern latitude positions at c. 580 Ma. Baltica during that time period was joined to Laurentia in a similar relative position to that at 750 Ma. The two shields then split up from each other and from c. 550 Ma Baltica drifted at moderately high latitudes and rotated some 180° during the final opening of the Iapetus ocean. This reconstruction suggests that during the Ediacaran glaciation Baltica occupied high-latitude positions, which contradicts the high-obliquity model to explain low-latitude Neoproterozoic glaciations
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| 6. |
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| 7. |
- Zaytseva, A, et al.
(author)
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Case Report: Loss-of-Function ABCC9 Genetic Variant Associated With Ventricular Fibrillation
- 2022
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In: Frontiers in genetics. - : Frontiers Media SA. - 1664-8021. ; 13, s. 718853-
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Journal article (other academic/artistic)abstract
- Genetic variants in the ABCC9 gene, encoding the SUR2 auxiliary subunit from KATP channels, were previously linked with various inherited diseases. This wide range of congenital disorders includes multisystem and cardiovascular pathologies. The gain-of-function mutations result in Cantu syndrome, acromegaloid facial appearance, hypertrichosis, and acromegaloid facial features. The loss-of-function mutations in the ABCC9 gene were associated with the Brugada syndrome, early repolarization syndrome, and dilated cardiomyopathy. Here, we reported a patient with a loss-of-function variant in the ABCC9 gene, identified by target high-throughput sequencing. The female proband presented with several episodes of ventricular fibrillation and hypokalemia upon emotional stress. This case sheds light on the consequences of KATP channel dysfunction in the cardiovascular system and underlines the complexity of the clinical presentation of ABCC9-related diseases.
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