Literature as premonition

There are many examples in literature, when writers managed to predict future. The essay examines this phenomenon on the basis of the novels by Russian writers, which contain parallels and prophetic premonitions of the events in Ukraine 2013-2014, the annexation of the Crimea and warnings against the consequences of these processes. The authors of this study do not aim at passing any political judgment or answering the question "Who is to blame?" but trying instead to say that attentive reading of classic literature might help to understand the processes of nowadays and avoid tragic mistakes. The novels addressed in the essay are written respectively in XX-th and XXI-th centuries: The White Guard by Mikhail Bulgakov, The Island of Crimea by Vasily Aksyonov and Sankya by Zakhar Prilepin. Hopefully, over time these events in Ukraine will gain a comprehensive understanding and will be given a deep and objective analysis, which is hardly possible today. Meanwhile we would like to outline the message inherent in the analyzed works: written in different time periods, sometimes separated by centuries, they express the desire of their authors to draw the readers to the eternal values of the world and suggest ways of overcoming war and discord

МАГНИТОФОРЕЗ И ОСОБЕННОСТИ КИСЛОРОДНОГО ОБМЕНА В РАЗБАВЛЕННОЙ СУСПЕНЗИИ ЭРИТРОЦИТОВ

Abstract. Oxygen exchange in single erythrocytes is studied with the use of magnetophoretic magnetometry based upon the registration of cell trajectories in a microfluidic Hele-Shaw cell under the action of high-gradient magnetic field. It is found that, at atmospheric conditions, the equilibrium oxygenation degree of cellular hemoglobin is four times smaller as against a standard level of blood hemoglobin. Also, an application of shear flow leads to an instantaneous increase of cellular hemoglobin oxygenation up to a standard level, and it takes minutes for a low equilibrium level to be re-established. These findings give a new notion as upon erythrocyte functions and may be of use for the hematocrit diagnosis.Особенности кислородного обмена отдельных эритроцитов изучены с помощью метода их магнитофоретической магнитометрии, основанного на регистрации траекторий движения клеток в микрожидкостной ячейке Хеле–Шоу при воздействии высокоградиентного магнитного поля. Впервые установлено, что в покоящейся разбавленной суспензии эритроцитов при атмосферном парциальном давлении кислорода степень оксигенации клеточного гемоглобина понижена в 4 раза по сравнению со стандартной оксигенацией гемоглобина крови. При этом приложение импульса сдвигового течения приводит к скачкообразному увеличению оксигенации до стандартного уровня, а восстановление низкого равновесного уровня оксигенации клеточного гемоглобина после прекращения течения происходит за время, измеряемое минутами. Полученные результаты выявляют новые особенности функционирования эритроцитов и могут найти применение для гематологической диагностики. 

ОДНОЧАСТИЧНАЯ И КОЛЛЕКТИВНАЯ МОДЫ МАГНИТНОЙ СЕПАРАЦИИ ЭРИТРОЦИТОВ

An experimental microfluidic model is proposed for studying magnetophoretic separation of submagnetic microparticles from liquid that ensures simple deterministic experimental conditions, the possibility of measuring the relevant physical properties of microparticles, their spatio-temporal distribution in diluted samples, and the process visualization in concentrated samples. Magnetic separation of red blood cells from deoxygenated diluted blood is studied. A phenomenon is discovered of the magnetophoretic granular Rayleigh–Taylor type instability that destroys the single-particle separation mode at cell volume concentration of about 0.002. The cell concentration growth is accompanied by enhancing the suspension vortex motion, but however this does not influence the time and the purity of the magnetic separation of red blood cells. From our observations, we have come to the conclusion that the hydrodynamic magnetophoretic instability should be related with mesoscopic swirls caused by the cell concentration dispersion. The concept of the magneto-gravitational analogy is formulated allowing one to consider the collective magnetophoresis of submagnetic microparticles as sedimentation in predetermined force fields. Our experimental model and the results obtained are of interest for the emerging technology of microfluidic analytical systems and for mechanics of suspensions as a whole.Предложена микрожидкостная экспериментальная модель для изучения магнитофоретической сепарации слабомагнитных микрочастиц из жидкости, обеспечивающая простые и хорошо детерминированные условия осуществления эксперимента, измерение определяющих процесс физических свойств частиц и в сильно разбавленных суспензиях регистрацию пространственно-временных характеристик их распределения, а также визуализацию процесса в суспензиях с увеличенной (до нескольких процентов) объемной концентрацией. Изучен процесс магнитной сепарации эритроцитов из разбавленной деоксигенированной цельной крови. Обнаружено явление магнитофоретической гранулярной неустойчивости типа неустойчивости Релея–Тейлора, нарушающее одночастичную моду сепарации при объемной концентрации клеток около 0,002. Увеличение концентрации сопровождается интенсификацией вихревого движения суспензии, что, однако, не оказывает в изученном диапазоне объемных концентраций до с = 0,023 заметного влияния на время и чистоту сепарации эритроцитов. На основе визуализации индивидуального поведения клеток сделан вывод о связи гидродинамической неустойчивости суспензии при магнитной сепарации с мезоскопическими вихревыми структурами, обусловленными пространственной дисперсией концентрации клеток. Сформулирована концепция магнито-гравитационной аналогии, позволяющая рассматривать коллективный магнитофорез как коллективную седиментацию в заданном силовом поле. Разработанный метод и полученные результаты представляют интерес для технологии микрожидкостных диагностических систем, для механики суспензий в целом

МАГНИТОФОРЕТИЧЕСКИЙ МЕТОД ИССЛЕДОВАНИЯ РАСПРЕДЕЛЕНИЯ ЭРИТРОЦИТОВ ПО СТЕПЕНИ ОКСИГЕНАЦИИ ГЕМОГЛОБИНА

The method is developed for a simultaneous differentiation of red blood cells in terms of magnetic susceptibility, hemoglobin oxygenation, and sedimentation velocity based upon video recording and automated handling of cell motion trajectories in a thin microfluidic channel under the action of crossed gravitational and high-gradient magnetic fields. The study of suspension of red blood cells with a low oxygen partial pressure, for the first time, revealed the existence of cell fractions with considerably reduced and increased hemoglobin oxygenation, which is presumably related with a weakened oxygen transport function of old red blood cells. Our method creates additional possibilities of studying native and pathogenic processes in red blood cells, and can be useful for medical diagnostics.Разработан метод одновременного измерения распределения эритроцитов по магнитной восприимчивости и степени оксигенации их гемоглобина, а также скорости седиментации клеток в жидкости, основанный на видеорегистрации и автоматизированной обработке траекторий их движения в плоском микрожидкостном канале при воздействии гравитационного и высокоградиентного магнитных полей. Исследование суспензии эритроцитов с низким парциальным давлением кислорода впервые выявило существование фракций эритроцитов с заметно пониженным и повышенным содержанием кислорода в условиях его дефицита, что может быть связано с ослаблением основной транспортной функции стареющих эритроцитов. Предложенный метод создает дополнительные возможности исследования эритроцитов в норме и при патологиях, имеет перспективы в медицинской диагностике

First-principles quantum transport modeling of spin-transfer and spin-orbit torques in magnetic multilayers

We review a unified approach for computing: (i) spin-transfer torque in magnetic trilayers like spin-valves and magnetic tunnel junction, where injected charge current flows perpendicularly to interfaces; and (ii) spin-orbit torque in magnetic bilayers of the type ferromagnet/spin-orbit-coupled-material, where injected charge current flows parallel to the interface. Our approach requires to construct the torque operator for a given Hamiltonian of the device and the steady-state nonequilibrium density matrix, where the latter is expressed in terms of the nonequilibrium Green's functions and split into three contributions. Tracing these contributions with the torque operator automatically yields field-like and damping-like components of spin-transfer torque or spin-orbit torque vector, which is particularly advantageous for spin-orbit torque where the direction of these components depends on the unknown-in-advance orientation of the current-driven nonequilibrium spin density in the presence of spin-orbit coupling. We provide illustrative examples by computing spin-transfer torque in a one-dimensional toy model of a magnetic tunnel junction and realistic Co/Cu/Co spin-valve, both of which are described by first-principles Hamiltonians obtained from noncollinear density functional theory calculations; as well as spin-orbit torque in a ferromagnetic layer described by a tight-binding Hamiltonian which includes spin-orbit proximity effect within ferromagnetic monolayers assumed to be generated by the adjacent monolayer transition metal dichalcogenide.Comment: 22 pages, 9 figures, PDFLaTeX; prepared for Springer Handbook of Materials Modeling, Volume 2 Applications: Current and Emerging Material

Internet as the means of Spanish study as a foreign language

© Medwell Journals, 2015. The study considers the role of Internet in the study of Spanish as a foreign language and the possibility of internet resources use in a planned learning. The method of planning is one of the innovative trends in modern professional study of a Foreign language. Its use during a Foreign language lesson not only motivates a student to a real communication but also promotes the development of intellectual and analytical abilities of a learner in the process of practical tasks implementation. The factual material for the article was the results of the survey conducted among KFU students studying Spanish as a first and a second Foreign language. The survey showed that 95% of students actively use Internet to learn the language. Along with the analysis of the most common and effective ways to get practical information and improve the language skills of the students (the reading of authentic newspapers, online TV watching, listening to radio, etc.) the study provides the recommendations for Spanish teachers concerning the productive use of internet resources during a classroom and the means of their incorporation in a planned learning methodology. The most popular resources of the internet system and the impact of their application to improve the communicative competence of students are considered

Internet as the means of Spanish study as a foreign language

© Medwell Journals, 2015. The study considers the role of Internet in the study of Spanish as a foreign language and the possibility of internet resources use in a planned learning. The method of planning is one of the innovative trends in modern professional study of a Foreign language. Its use during a Foreign language lesson not only motivates a student to a real communication but also promotes the development of intellectual and analytical abilities of a learner in the process of practical tasks implementation. The factual material for the article was the results of the survey conducted among KFU students studying Spanish as a first and a second Foreign language. The survey showed that 95% of students actively use Internet to learn the language. Along with the analysis of the most common and effective ways to get practical information and improve the language skills of the students (the reading of authentic newspapers, online TV watching, listening to radio, etc.) the study provides the recommendations for Spanish teachers concerning the productive use of internet resources during a classroom and the means of their incorporation in a planned learning methodology. The most popular resources of the internet system and the impact of their application to improve the communicative competence of students are considered

Literature as premonition

There are many examples in literature, when writers managed to predict future. The essay examines this phenomenon on the basis of the novels by Russian writers, which contain parallels and prophetic premonitions of the events in Ukraine 2013-2014, the annexation of the Crimea and warnings against the consequences of these processes. The authors of this study do not aim at passing any political judgment or answering the question "Who is to blame?" but trying instead to say that attentive reading of classic literature might help to understand the processes of nowadays and avoid tragic mistakes. The novels addressed in the essay are written respectively in XX-th and XXI-th centuries: The White Guard by Mikhail Bulgakov, The Island of Crimea by Vasily Aksyonov and Sankya by Zakhar Prilepin. Hopefully, over time these events in Ukraine will gain a comprehensive understanding and will be given a deep and objective analysis, which is hardly possible today. Meanwhile we would like to outline the message inherent in the analyzed works: written in different time periods, sometimes separated by centuries, they express the desire of their authors to draw the readers to the eternal values of the world and suggest ways of overcoming war and discord

Literature as premonition

There are many examples in literature, when writers managed to predict future. The essay examines this phenomenon on the basis of the novels by Russian writers, which contain parallels and prophetic premonitions of the events in Ukraine 2013-2014, the annexation of the Crimea and warnings against the consequences of these processes. The authors of this study do not aim at passing any political judgment or answering the question "Who is to blame?" but trying instead to say that attentive reading of classic literature might help to understand the processes of nowadays and avoid tragic mistakes. The novels addressed in the essay are written respectively in XX-th and XXI-th centuries: The White Guard by Mikhail Bulgakov, The Island of Crimea by Vasily Aksyonov and Sankya by Zakhar Prilepin. Hopefully, over time these events in Ukraine will gain a comprehensive understanding and will be given a deep and objective analysis, which is hardly possible today. Meanwhile we would like to outline the message inherent in the analyzed works: written in different time periods, sometimes separated by centuries, they express the desire of their authors to draw the readers to the eternal values of the world and suggest ways of overcoming war and discord