The complete reducibility of some GF(2)A7-modules

It is proved that, if G is a finite group with a nontrivial normal 2-subgroup Q such that G/Q ∼= A 7 and an element of order 5 from G acts freely on Q, then the extension G over Q is splittable, Q is an elementary abelian group, and Q is the direct product of minimal normal subgroups of G each of which is isomorphic, as a G/Q-module, to one of the two 4-dimensional irreducible GF(2)A7-modules that are conjugate with respect to an outer automorphism of the group A7. © 2013 Pleiades Publishing, Ltd

Finite simple exceptional groups of Lie type in which all subgroups of odd index are pronormal

A subgroup H of a group G is said to be pronormal in G if H and H g are conjugate in 〈 H, H g〉 for every g ∈ G. In this paper, we determine the finite simple groups of type E 6 (q) and E 6 2 (q) in which all the subgroups of odd index are pronormal. Thus, we complete a classification of finite simple exceptional groups of Lie type in which all the subgroups of odd index are pronormal. © 2020 Walter de Gruyter GmbH, Berlin/Boston 2020.This work was supported by the Russian Science Foundation (project 19-71-10067)

ЭКСПЕРТНАЯ ОЦЕНКА САМОДЕЛЬНЫХ ГРАНАТ ДЛЯ СТРАЙКБОЛА

The paper presents the results of forensic analysis of improvised dummy grenades modeled after the airsoft hand grenade RGS-4 for use in tactical simulation wargames like «Airsoft». Initial testing by experts affiliated with a different system of forensic science institutes led to the conclusion that these devices are capable of producing explosions and causing fragmentation damage. The purpose of this study conducted by two forensic science centers of the Ministry of Justice of the Russian Federation was to correct the classification of improvised devices as explosive devices. Results indicate that these devices that consist of a cardboard (paper) or rubber-like casing filled with dried peas, with a «Korsar-4» firecracker in the middle, have the formal characteristics of an explosive device but cannot be regarded as such (as per Article 222 of the Criminal Code of the Russian Federation), since they are in effect typical imitation pyrotechnic devices similar to dummy hand grenades RGS-4 and display no significant damaging properties.Приведены результаты экспертных исследований самодельных имитационных гранат типа РГС-4, используемых в сценарной военно-тактической игре «Страйкбол», которые ранее по результатам взрывотехнических экспертиз, выполненных в другой экспертной системе России, признали пригодными для производства взрыва и обладающими поражающим осколочным действием. Повторные экспертизы, проведенные в судебно-экспертных учреждениях Минюста России, установили, что эти самодельные имитационные гранаты хотя и имеют формальные признаки взрывного устройства, но не могут быть классифицированы как взрывные (по ст. 222 УК РФ), поскольку являются типичными имитационно-пиротехническими изделиями и не обладают выраженными поражающими свойствами

Precanonical quantization of Yang-Mills fields and the functional Schroedinger representation

Precanonical quantization of pure Yang-Mills fields, which is based on the covariant De Donder-Weyl (DW) Hamiltonian formalism, and its connection with the functional Schrodinger representation in the temporal gauge are discussed. The YM mass gap problem is related to a finite dimensional spectral problem for a generalized Clifford-valued magnetic Schr\"odinger operator in the space of gauge potentials which represents the DW Hamiltonian operator.Comment: LaTeX2e, 11pages. v2: 13 pages, minor changes, references added, sect. 5 extended, to appear in Rep. Math. Phy

Landscape science: a Russian geographical tradition

The Russian geographical tradition of landscape science (landshaftovedenie) is analyzed with particular reference to its initiator, Lev Semenovich Berg (1876-1950). The differences between prevailing Russian and Western concepts of landscape in geography are discussed, and their common origins in German geographical thought in the late nineteenth and early twentieth centuries are delineated. It is argued that the principal differences are accounted for by a number of factors, of which Russia's own distinctive tradition in environmental science deriving from the work of V. V. Dokuchaev (1846-1903), the activities of certain key individuals (such as Berg and C. O. Sauer), and the very different social and political circumstances in different parts of the world appear to be the most significant. At the same time it is noted that neither in Russia nor in the West have geographers succeeded in specifying an agreed and unproblematic understanding of landscape, or more broadly in promoting a common geographical conception of human-environment relationships. In light of such uncertainties, the latter part of the article argues for closer international links between the variant landscape traditions in geography as an important contribution to the quest for sustainability

Оценка эффективности лечения новообразований печени по данным КТ и МРТ: дорожная карта для врача лучевой диагностики

The number of available methods for hepatic tumor treatment is steadily increasing. Except traditional surgical resection and systemic chemotherapy there are a lot of effective and increasingly used local methods such as Radiofrequency ablation, cryodestruction, transarterial chemoembolization. Radiologist should be able to assess treatment response and evaluate prognosis. We present review of literature on various systems for hepatic tumor treatment response evaluation. WHO, RECIST 1.0, RECIST 1.1, mRECIST and Choi criteria are thoroughly explained in terms of benefits and drawbacks. Also, texture analysis and diffusion-weighted imaging are discussed.В последние годы выбор различных вариантов терапии образований печени становится все шире, отмечается появление новых вариантов химио- и лучевой терапии. В настоящее время растет количество методов локального воздействия на опухоли, таких как радиочастотная абляция, криодеструкция, трансартериальная эмболизация. Клиническая оценка эффекта терапии не дает необходимого результата, поэтому возрастает потребность в адекватной оценке результатов лечения, основанной на данных методов КТ и МРТ. В данном литературном обзоре приводятся основные критерии оценки эффективности лечения опухолей различными видами воздействия. Отдельно рассматриваются критерии ВОЗ, RECIST, RECIST 1.1, mRECIST, Choi. Помимо этого обсуждаются новые методики объективизации эффектов терапии, основанные на оценке диффузионно-взвешенных изображений и текстурном анализе