A quantum hydrodynamics approach to the formation of new types of waves in polarized two-dimension systems of charged and neutral particles

In this paper we explicate a method of quantum hydrodynamics (QHD) for the study of the quantum evolution of a system of polarized particles. Though we focused primarily on the two-dimension physical systems, the method is valid for three-dimension and one-dimension systems too. The presented method is based upon the Schr\"{o}dinger equation. Fundamental QHD equations for charged and neutral particles were derived from the many-particle microscopic Schr\"{o}dinger equation. The fact that particles possess the electric dipole moment (EDM) was taken into account. The explicated QHD approach was used to study dispersion characteristics of various physical systems. We analyzed dispersion of waves in a two-dimension (2D) ion and hole gas placed into an external electric field which is orthogonal to the gas plane. Elementary excitations in a system of neutral polarized particles were studied for 1D, 2D and 3D cases. The polarization dynamics in systems of both neutral and charged particles is shown to cause formation of a new type of waves as well as changes in the dispersion characteristics of already known waves. We also analyzed wave dispersion in 2D exciton systems, in 2D electron-ion plasma and 2D electron-hole plasma. Generation of waves in 3D system neutral particles with EDM by means of the beam of electrons and neutral polarized particles is investigated.Comment: 15 pages, 7 figure

Breeding behavior and pup development of the Caspian seal, Pusa caspica

The Caspian seal, Pusa caspica, is an ice-breeding phocid endemic to the Caspian Sea. The breeding behavior of this species is poorly documented. Here, we report behavioral observations of 518 mother-pup pairs and 210 lone pups, made from the bridge of icebreakers traversing seal breeding grounds while servicing oil installations in the northeastern Caspian Sea, during 34 trips from late January to early March, 2006-2012. The breeding habitat of Caspian seals is land-fast or drift ice, usually at least 20 cm thick, overlying water 3–5 m deep. Pregnant females formed pairs or small groups. They were not observed to use lairs, but preferentially pupped beside ice ridges or ice-slab piles that afforded shelter to pups. In years when there were few natural leads into the ice-field, females often gave birth on the edge of artificial leads formed by shipping channels. Pups were categorized into stages from newborn (1), white-coat (2), molting (3), and molted (4), with Stage 3 and 4 pups appearing from mid to late February. The nursing period lasted at least 3 weeks and neighboring mother-pup pairs appeared to be mutually tolerant. Mothers left their pups alone or at nursery sites, presumably to forage. Most white-coat pups moved over the ice while avoiding water in response to disturbance from vessels. Mother-pup pairs maintained contact while moving across the ice by a combination of the pup’s following response and diligent chaperoning by the mother. During disturbances some lone pups sought refuge in shelters under ice slabs, whereas others followed a neighboring mother-pup pair away from the vessel. Male-female pairing occurred in late season with no male-male competition observed on the ice. While breeding and pup rearing behavior of Caspian seals has some features in common with that of other Holarctic seals, it is largely distinct and adapted to the unique conditions of the Caspian environment, in particular the paucity of snow cover on the ice

Combined Effect of Microstructure, Surface Energy, and Adhesion Force on the Friction of PVA/Ferrite Spinel Nanocomposites

Nanocomposite films based on spinel ferrite (Mg0.8Zn0.2Fe1.5Al0.5O4) in a PVA matrix were obtained. An increase in the spinel concentration to 10 wt.% caused an avalanche-like rise in roughness due to the formation of nanoparticle agglomerates. The lateral mode of atomic force microscopy (AFM) allowed us to trace the agglomeration dynamics. An unexpected result was that the composite with 6 wt.% of filler had a low friction coefficient in comparison with similar composites due to the successfully combined effects of low roughness and surface energy. The friction coefficient decreased to 0.07 when the friction coefficient of pure PVA was 0.72. A specially developed method for measuring nano-objects’ surface energy using AFM made it possible to explain the anomalous nature of the change in tribological characteristics. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.National University of Science and Technology, MISISAlex V. Trukhanov thanks NUST MISIS for support within the framework of the «Priority 2030»

Investigation of thin films MgAl2O4, deposited on the Si substrates by vacuum thermal evaporation

The article presents data on the study of X-ray structural and microstructural characteristics of thin films of aluminum-magnesium spinel MgAl2O4 deposited on Si substrates by vacuum thermal evaporation. MgAl2O4 films have a polycrystalline rhombic structure. The values of the unit cell parameters of MgAl2O4 are calculated. Scanning electron and atomic force microscopy showed that MgAl2O4 films have a densely packed structure without cracks. Physical characteristics and good adhesion of MgAl2O4 thin films to silicon substrates indicate their possibility of using in devices of opto- and microelectronics

Features of central hemodynamics in women with multiple pregnancy (literature review)

Over the past decades, there has been an increase in the incidence of multiple pregnancies, which is associated with an increase in the age of parturient women, the widespread use of assisted reproductive technologies, the prolonged intake of hormonal oral contraceptives, and stimulants of ovulation. The cardiovascular system in pregnant women with multiple births undergoes major changes, which leads to a significant transformation of hemodynamic parameters. All changes in the work of the CCC of a pregnant woman are due to the formation of an additional utero-placental circle of blood circulation. Changes in the work of the cardiovascular system are associated with both hemodynamic and mechanical factors. Restructuring of the circulatory system during pregnancy consists in an increase in BCC against a background of increased capacity of the vascular bed and cardiac output, when cardiac output increases significantly. These changes provide a higher level of performance for various maternal systems, corresponding to the increasing energy and metabolic needs of the fetus.В течение последних десятилетий наблюдается рост частоты многоплодных беременностей, что связано с увеличением возраста рожениц, широким применением вспомогательных репродуктивных технологий, длительным приемом гормональных оральных контрацептивов, а также стимуляторов овуляции. Сердечно-сосудистая система у беременных с многоплодием претерпевает серьезные изменения, что приводит к значительной трансформации гемодинамических показателей. Все изменения в работе ССС беременной женщины обусловлены формированием дополнительного маточно-плацентарного круга кровообращения. Изменения работы сердечно-сосудистой системы связаны как с гемодинамическими, так и с механическими факторами. Перестройка системы кровообращения при беременности заключается в увеличении ОЦК на фоне повышения емкости сосудистого русла и производительности сердца, когда сердечный выброс увеличивается значительно. Эти изменения обеспечивают более высокий уровень работы различных систем матери, соответствующий возрастающим энергетическим и метаболическим потребностям плода

Structure, Morphology and Electrical/Magnetic Properties of Ni-Mg Nano-Ferrites from a New Perspective

Using the auto combustion flash method, Ni1−x+2 Mg+2xFe+32O4 (x = 0, 0.2, 0.6, 0.8 and 1) nano-ferrites were synthesized. All samples were thermally treated at 973 K for 3 h. The structural analysis for the synthesized samples was performed using XRD, high-resolution transmission electron microscopy (HRTEM), and FTIR. Scanning electron microscopy (SEM) was undertaken to explore the surface morphology of all the samples. The thermal stability of these samples was investigated using thermogravimetric analysis (TGA). XRD data show the presence of a single spinel phase for all the prepared samples. The intensity of the principal peak of the spinel phase decreases as Mg content increases, showing that Mg delays crystallinity. The Mg content raised the average grain size (D) from 0.084 µm to 0.1365 µm. TGA shows two stages of weight loss variation. The vibrating sample magnetometer (VSM) measurement shows that magnetic parameters, such as initial permeability (µi) and saturation magnetization (Ms), decay with rising Mg content. The permeability and magnetic anisotropy at different frequencies and temperatures were studied to show the samples’ magnetic behavior and determine the Curie temperature (TC), which depends on the internal structure. The electrical resistivity behavior shows the semi-conductivity trend of the samples. Finally, the dielectric constant increases sharply at high temperatures, explained by the increased mobility of charge carriers, and decreases with increasing frequency. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Princess Nourah Bint Abdulrahman University, PNU: PNURSP2022R28The authors express their gratitude to Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2022R28), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia

Гипоксические белки VEGF A и CA IX и резистентность клеток сарком мягких тканей к химиопрепаратам: пилотный опыт ex vivo анализа

Introduction. The identification of predictive factors is a cornerstone task of modern oncology. The development of new targeted drugs determines the need for prediction of chemosensitivity of each patient to the prescribed therapy, in this regard, the search for biomarkers of predictive response to therapy is actively conducted.The study objective to investigate the relationship between tumor cell resistance and the expression levels of CA IX (carbonic anhydrase IX) and VEGF A (vascular endothelial growth factor А) in patient-derived cultures of soft tissue sarcomas.Materials and methods: ex vivo soft tissue sarcoma cell culture, resazurin test, immunoblotting.Results. We obtained 46 ex vivo samples of soft tissue sarcoma cultures for which chemosensitivity to doxorubicin, ifosfamide, docetaxel, gemcitabine, and their combinations was assessed by the resazurin cytotoxicity test. We analyzed the relationship between the expression of hypoxic proteins VEGF A and CA IX and the resistance to drugs. A correlation between the CA IX expression in hypoxia and cell resistance to ifosfamide and its combination with doxorubicin was found. Soft tissue sarcomas with high VEGF A index were resistant to doxorubicin, docetaxel, and its combination with gemcitabine (p <0.05).Conclusion. The data obtained on patient-derived cultures indicate the relationship between hypoxic signaling and resistance of soft tissue sarcomas to chemotherapeutics.Введение. Поиск предиктивных факторов является краеугольной задачей современной онкологии. Разработка большого числа новых таргетных препаратов определяет необходимость четкого предсказания хемочувствительности конкретного пациента к назначаемой терапии. В связи с этим активно ведется поиск биомаркеров прогноза ответа на терапию.Цель исследования – изучение взаимосвязи между резистентностью опухолевых клеток и уровнем экспрессии CA IX (карбоангидразы IX) и VEGF A (фактора роста эндотелия сосудов А) в ex vivo культурах сарком мягких тканей.Материалы и методы. В исследование были включены ex vivo культуры сарком мягких тканей, использованы резазуриновый тест, иммуноблоттинг.Результаты. Получено 46 ex vivo образцов культур сарком мягких тканей, для которых с помощью резазуринового теста на цитотоксичность определена хемочувствительность к доксорубицину, ифосфамиду, доцетакселу, гемцитабину и их комбинациям. Проведен анализ связи экспрессии гипоксических белков VEGF A и CA IX с резистентностью к химиопрепаратам. Обнаружена корреляция уровня экспрессии CA IX в гипоксии с резистентностью клеток к ифосфамиду и его комбинации с доксорубицином. Образцы сарком мягких тканей, обладающие высоким индексом VEGF A, были резистентны к доксорубицину, доцетакселу и его комбинации с гемцитабином (p <0,05).Заключение. Полученные на ex vivo культурах данные свидетельствуют о взаимосвязи гипоксического сигналинга и резистентности сарком мягких тканей к химиотерапии

Противоопухолевое действие кураксина CBL0137 на моделях аденокарциномы толстой кишки

Curaxins represent low molecular weight carbazole derivatives, which simultaneously activate p53-dependent apoptosis and inhibit NF-kBdependent signal transduction pathways. Antitumor activity of curaxin CBL0137 was demonstrated in vivo on the model of solid transplantable mouse colon adenocarcinoma Akatol. Significant tumor growth inhibition caused by CBL0137 treatment was observed. On the 37th day after tumor transplantation for CBL0137 oral doses 5, 10, 15 and 20 mg/kg the tumor growth inhibition indexes were 53, 50, 56 and 74 %, respectively. CBL0137 treatment extended life span of mice in all study groups receiving this test article. Maximum lifespan increase (81,7 %) was observed in the group of mice treated with 20 mg/kg dose of CBL0137. The cytotoxicity of CBL0137 was assessed on human colon cancer cells in vitro. We demonstrated that CBL0137 inhibits the expression COX2, which in its turn is known to exhibit antiapoptotic, pro-angiogenic and pro- metastatic properties. Thus, we demonstrated antitumor effect of CBL0137 against colon cancer in vitro and in vivo.Кураксины представляют собой низкомолекулярные карбазольные производные, обладающие афинностью к ДНК, способные одновременно активировать р53-зависимый апоптоз и ингибировать NF-kB-зависимый сигнальный путь. На модели перевиваемой аденокарциномы толстой кишки (Aкатол) на мышах линии BALB/c продемонстрировано противоопухолевое действие кураксина CBL0137. Наблюдалось значительное тормозящее действие CBL0137 на рост данной аллографтной опухоли: на 37-е сутки после перевивки опухоли при пероральном введении препарата в дозах 5, 10, 15 и 20 мг/кг в день торможение роста опухоли составило 53, 50, 56 и 74 % соответственно. Значимое увеличение продолжительности жизни наблюдалось во всех группах животных, получавших CBL0137. Максимальный эффект (81,7 %) был получен при введении препарата в дозе 20 мг/кг в день. В экспериментах in vitro при обработке клеток аденокарциномы толстой кишки человека HTC116 наблюдался значительный цитотоксический эффект. CBL0137 проявил способность ингибировать экспрессию гена COX2, обладающего антиапоптотическим действиеми способностью стимулировать неоангиогенез и метастазирование. Таким образом, в системах in vivo и in vitro продемонстрировано противоопухолевое действие CBL0137 в отношении аденокарциномы толстой кишки

Large-scale unit commitment under uncertainty: an updated literature survey

The Unit Commitment problem in energy management aims at finding the optimal production schedule of a set of generation units, while meeting various system-wide constraints. It has always been a large-scale, non-convex, difficult problem, especially in view of the fact that, due to operational requirements, it has to be solved in an unreasonably small time for its size. Recently, growing renewable energy shares have strongly increased the level of uncertainty in the system, making the (ideal) Unit Commitment model a large-scale, non-convex and uncertain (stochastic, robust, chance-constrained) program. We provide a survey of the literature on methods for the Uncertain Unit Commitment problem, in all its variants. We start with a review of the main contributions on solution methods for the deterministic versions of the problem, focussing on those based on mathematical programming techniques that are more relevant for the uncertain versions of the problem. We then present and categorize the approaches to the latter, while providing entry points to the relevant literature on optimization under uncertainty. This is an updated version of the paper "Large-scale Unit Commitment under uncertainty: a literature survey" that appeared in 4OR 13(2), 115--171 (2015); this version has over 170 more citations, most of which appeared in the last three years, proving how fast the literature on uncertain Unit Commitment evolves, and therefore the interest in this subject