Alfven Wave-Driven Supernova Explosion

We investigate the role of Alfven waves in the core-collapse supernova (SN) explosion. We assume that Alfven waves are generated by convections inside a proto-neutron star (PNS) and emitted from its surface. Then these waves propagate outwards, dissipate via nonlinear processes, and heat up matter around a stalled prompt shock. To quantitatively assess the importance of this process for the revival of the stalled shock, we perform 1D time-dependent hydrodynamical simulations, taking into account the heating via the dissipation of Alfven waves that propagate radially outwards along open flux tubes. We show that the shock revival occurs if the surface field strength is larger than ~2e15 G and if the amplitude of velocity fluctuation at the PNS surface is larger than 20% of the local sound speed. Interestingly, the Alfven wave mechanism is self-regulating in the sense that the explosion energy is not very sensitive to the surface field strength and initial amplitude of Alfven waves as long as they are larger than the threshold values given above.Comment: 7 pages, 3 figures embedded, submitted to Ap

Numerical Simulations of Equatorially-Asymmetric Magnetized Supernovae: Formation of Magnetars and Their Kicks

A series of numerical simulations on magnetorotational core-collapse supernovae are carried out. Dipole-like configurations which are offset northward are assumed for the initially strong magnetic fields together with rapid differential rotations. Aims of our study are to investigate effects of the offset magnetic field on magnetar kicks and on supernova dynamics. Note that we study a regime where the proto-neutron star formed after collapse has a large magnetic field strength approaching that of a ``magnetar'', a highly magnetized slowly rotating neutron star. As a result, equatorially-asymmetric explosions occur with a formation of the bipolar jets. Resultant magnetar's kick velocities are $\sim 300-1000$ km s$^{-1}$. We find that the acceleration is mainly due to the magnetic pressure while the somewhat weaker magnetic tension works toward the opposite direction, which is due to stronger magnetic field in the northern hemisphere. Noted that observations of magnetar's proper motions are very scarce, our results supply a prediction for future observations. Namely, magnetars possibly have large kick velocities, several hundred km s$^{-1}$, as ordinary neutron stars do, and in an extreme case they could have those up to 1000 km s$^{-1}$.Comment: 36 pages, 9 figures, accepted by the Astrophysical Journa

Influence of stress concentrator shape and testing temperature on impact fracture regularities of pipeline steel

The structure and impact toughness of the pipeline 17Mn1Si steel have been studied. The main attention was paid to the analysis of various conditions of stress concentration under dynamic loadings. The process of strain localization with increasing stress state stiffness at the tip of the concentrator with decreasing testing temperature was investigated. Impact loading diagrams for specimens with various stress concentrator shapes were registered and analyzed

Material fragmentation as dissipative process of micro rotation sequence formation: Hybrid model of excitable cellular automata

The authors have developed a multi-level model of energy propagation along interfaces between the various structural elements of a solid with taking into account mutual energy transformations of various kinds. They have also designed a computer simulation tool based on the excitable cellular automaton (ECA) method. An algorithm for calculating the local moments of forces has been developed for the case of material rotation and torsion. The relationship for the accumulated elastic energy is supplemented with a dissipation term. Numerical experiments have been carried out on high-energy impact on polycrystalline copper specimens with different grain sizes. The paper shows that during the nanostructuring of material surface layer, the dissipation of elastic energy gives rise to the rotation of structural elements. This makes it possible to prevent the occurrence of stress concentrators with peak values typical of coarse-grained specimens and reducing their mechanical properties

Influence of stress concentrator shape and testing temperature on impact fracture regularities of pipeline steel

The structure and impact toughness of the pipeline 17Mn1Si steel have been studied. The main attention was paid to the analysis of various conditions of stress concentration under dynamic loadings. The process of strain localization with increasing stress state stiffness at the tip of the concentrator with decreasing testing temperature was investigated. Impact loading diagrams for specimens with various stress concentrator shapes were registered and analyzed

Influence of porosity on the deformation behaviour of systems with nanostructured thermal barier coatings

Based on the principal concepts of physical mesomechanics that take into account reversible structural-phase transformations in the rotational-wave flows at the interfaces, a new modification of the multilevel discrete-continuous method of excitable cellular automata (ECA) has been developed. The new modification explicitly takes into account the porosity and the nanocrystalline structure. Also, algorithms for calculating the local moments of forces and the angular velocities of microrotations arising in a structurally heterogeneous medium have been implemented. The model has been complemented by the dissipation conditions expressed for mechanical energy flows. On the basis of the method of excitable cellular automata, some numerical experiments on thermal loading of three-layered compositions with the intermediate layers of different structures have been carried out. It is shown that nanostructuring of the intermediate sublayer and the introduction of nanoporosity gives rise to a positive effect on the relaxation ability of thermal barrier coatings

V. V. Lapin, A. I. Miller (Eds.). (2021). Simvolicheskie aspekty politiki pamiati v sovremennoi Rossii i vostochnoi Evrope [Symbolic aspects of the politics of memory in modern Russia and Eastern Europe]. EUSP Press

Received 25 August 2022. Published online 10 October 2022.This review is an abridged and revised version of Rusakova O. F., Gribovod E. G., & Moiseenko Y. Yu. (2022). Diskurs politiki pamiati: Issledovaniia simvolicheskikh aspektov [Discourse on the politics of memory: Studies of symbolic aspects]. Discourse-P, 19(2), pp. 154–171. https://doi.org/10.17506/18179568_2022_19_2_154Review of the book by V. V. Lapin, A. I. Miller (Eds.). (2021). Symbolic aspects of the politics of memory in modern Russia and Eastern Europe]. EUSP Press.This work was supported by the Russian Foundation for Basic Research under Grant No. 21-011-43023 “The official discourse of Russian politics of memory concerning the Soviet past: interpretation strategies, actors and commemorative practices.

КЛЕТОЧНАЯ ИММУННАЯ РЕАКЦИЯ ПРИ МЕТАСТАЗАХ В БОЛЬШОМ САЛЬНИКЕ ПРИ РАКЕ ЯИЧНИКОВ

Introduction. Ovarian cancer is characterized by complex diagnostics and flow forecasting, which makes it important to search for prognostic criteria. However, the prognostic significance of some factors has not yet been studied.The purpose of the study: to identify the features of immune response in the localization of metastases in the large omentum in ovarian cancer.Tasks: to reveal the pathomorphological features of the cellular immune response to metastases in the large omentum in patients with ovarian cancer II–III stages; to conduct histomorphometry of elements of the immune system in the area of metastases.Material and methods. The study was carried out on the biomaterial of the large omentum of 94 women with ovarian cancer II–III stage. The measurements were carried out on paraffin sections stained with hematoxylin and eosin and included evaluation of the following parameters: the number of lymphocytes in the field of view at the border and away from the tumor, the continuity of the lymphocyte shaft at the border with the tumor, the number of neutrophils on the border with the tumor, the presence of plasmocytes on the border with tumor. The preparations were studied and photographed under a microscope with a microscope-microvision mVizo-103 and a microscope Micromed 3.The results. Observed 94 patients with stage II–III ovarian cancer. Over the three-year follow-up period, the disease-free survival rate was 79.8%. A total of 64 patients with stage III disease were observed. A recurrence-free survival rate among patients with stage III ovarian cancer was 74.32%. Without relapse during the follow-up period, those patients were found whose lymphocytes formed a continuous shaft at the border with the tumor, their number in the field of view ×200 was 400 or more, the plasmocytes were present in the composition of the shaft, and the neutrophils were absent or few.The conclusion. A detailed histological study to quantify and qualitatively determine the severity of lymphoid elements of the large omentum allowed an indirect assessment of the state of the immune system and the probability of an unfavorable outcome in patients with ovarian neoplasia. Введение. Рак яичников отличается затрудненными диагностикой и прогнозированием течения, что делает актуальным поиск прогностических критериев. Однако прогностическое значение некоторых факторов до сих пор не изучено.Цель исследования: выявить особенности клеточной иммунной реакции в местах локализации метастазов в большой сальник при раке яичников.Задачи: выявить патоморфологические особенности иммунной реакции на метастазы в большом сальнике у больных раком яичников II–III стадий; провести гистоморфометрию элементов иммунной системы в области метастазов.Материал и методы исследования. Исследовался большой сальник 94 женщин больных раком яичников II–III стадий. Измерения проводились на парафиновых срезах, окрашенных гематоксилином и эозином, оценивали параметры: количество лимфоцитов в поле зрения на границе и на удалении от опухоли, непрерывность лимфоцитарного вала на границе с опухолью, количество нейтрофилов на границе с опухолью, наличие плазмоцитов на границе с опухолью. Применялся микроскоп-микровизор mVizo-103 и микроскоп «Микромед 3».Результаты и их обсуждение. Наблюдались 94 больных раком яичников II–III стадий. За трехлетний период наблюдения безрецидивная выживаемость составила 79,8%. Всего наблюдалось 64 больных с III стадией заболевания. Безрецидивная выживаемость среди пациенток с III стадией рака яичников составила 74,32%. Без рецидива за время наблюдения находились те больные, у которых лимфоциты образовывали непрерывный вал на границе с опухолью, их количество в поле зрения ×200 составляло 400 и более, в составе вала имелись плазмоциты, а нейтрофилы отсутствовали или немногочисленны.Заключение: гистологическое исследование большого сальника позволяло косвенно оценить состояние иммунной системы и вероятность неблагоприятного исхода у больных с неоплазией яичников.

Benzene and toluene in the surface air of northern Eurasia from TROICA-12 campaign along the Trans-Siberian Railway

Volatile organic compounds (VOCs) were measured by proton transfer reaction mass spectrometry (PTR-MS) on a mobile laboratory in a transcontinental TROICA-12 (21 July–4 August 2008) campaign along the Trans-Siberian Railway from Moscow to Vladivostok. Surface concentrations of benzene (C6H6) and toluene (C7H8) along with non-methane hydrocarbons (NMHCs), CO, O3, SO2, NO, NO2 and meteorology are analyzed in this study to identify the main sources of benzene and toluene along the Trans-Siberian Railway. The most measurements in the TROICA-12 campaign were conducted under low-wind/stagnant conditions in moderately ( ∼  78 % of measurements) to weakly polluted ( ∼  20 % of measurements) air directly affected by regional anthropogenic sources adjacent to the railway. Only 2 % of measurements were identified as characteristic of highly polluted urban atmosphere. Maximum values of benzene and toluene during the campaign reached 36.5 and 45.6 ppb, respectively, which is significantly less than their short-term exposure limits (94 and 159 ppb for benzene and toluene, respectively). About 90 % of benzene and 65 % of toluene content is attributed to motor vehicle transport and 10 and 20 %, respectively, provided by the other local- and regional-scale sources. The highest average concentrations of benzene and toluene are measured in the industrial regions of the European Russia (up to 0.3 and 0.4 ppb for benzene and toluene, respectively) and south Siberia (up to 0.2 and 0.4 ppb for benzene and toluene, respectively). Total contribution of benzene and toluene to photochemical ozone production along the Trans-Siberian Railway is about 16 % compared to the most abundant organic VOC – isoprene. This contribution, however, is found to be substantially higher (up to 60–70 %) in urbanized areas along the railway, suggesting an important role of anthropogenic pollutant sources in regional ozone photochemistry and air quality