Application of hydrogenation to low-temperature cleaning of the Si(001) surface in the processes of molecular-beam epitaxy: Investigation by STM, RHEED and HRTEM

Structural properties of the clean Si(001) surface obtained as a result of low-temperature (470--650C) pre-growth annealings of silicon wafers in a molecular-beam epitaxy chamber have been investigated. To decrease the cleaning temperature, a silicon surface was hydrogenated in the process of a preliminary chemical treatment in HF and NH_4F aqueous solutions. It has been shown that smooth surfaces composed by wide terraces separated by monoatomic steps can be obtained by dehydrogenation at the temperatures > 600C, whereas clean surfaces obtained at the temperatures < 600C are rough. It has been found that there exists a dependence of structural properties of clean surfaces on the temperature of hydrogen thermal desorption and the process of the preliminary chemical treatment. The frequency of detachment/attachment of Si dimers from/to the steps and effect of the Ehrlich-Schwoebel barrier on ad-dimer migration across steps have been found to be the most probable factors determining a degree of the resultant surface roughness.Comment: 8 pages, 8 figures; version accepted to J. Appl. Phy

Pt(II) and Pd(II) Complexes with β-Alanine

A sequence of stages in the syntheses of isomeric bisamino acid complexes of Pt(II) with β-aminopropionic acid (β-alanine = β-AlaH) has been studied by the 195Pt NMR spectroscopy. The techniques have been developed of the synthesis of the cis- and trans-bischelates of Pt(II) and Pd(II) with β-alanine as well as of the halide complexes of trans-[M(β-AlaH)2Cl2] (M = Pt, Pd) and trans-K2[Pt(β-Ala)2I2] types. The NMR spectroscopy and IR spectroscopy (in the nuclei of 195Pt,13C,1H) and X-ray diffraction analysis have been used to examine the structures of the synthesized compounds

Криптовалюты vs цифровые валюты центральных банков: роль финансовой грамотности населения

A bifurcation point has arisen in the transformation of the global monetary and financial system, associated with its further digital transformation: will it be based on private digital currencies like Bitcoin, or on the basis of central bank digital currencies (CBDC)? To a large extent, this depends on the willingness of economic agents to use virtual currencies.The purpose of the study is to explore the factors determining the attitude of economic agents to digital currencies and the impact of financial literacy on using these instruments as an investment object and means of payment.The authors use the following research methods: content analysis, retrospective analysis, methods of comparative cross-country analysis, and empirical research in the form of an online survey of graduate financial students. This study is one of the first to reveal differences in the assessment of their knowledge and readiness to use digital currencies of financial and non-financial students, as well as to confirm an adequate assessment of the risks and opportunities of different types of virtual currencies if students have financial knowledge. The research shows that the situation with the decisionmaking of economic agents on the use of cryptocurrencies and the CBDC differs: in the first case, the initiative comes from the economic agents themselves, who make decisions at their own peril and risk; in the second case, economic agents are confronted with the fact of the existence of the CBDC and the need to use them.The authors conclude that the population’s low financial and digital literacy can create a mental barrier to the use of CBDC, complicating their implementation in national monetary systems. The lack of financial literacy leads to an exaggeration of their knowledge by participants in the cryptocurrency market.В настоящее время в трансформации мировой валютно-финансовой системы возникла точка бифуркации, связанная с определением путей ее дальнейшей цифровой трансформации: будет ли она проходить на основе частных цифровых валют типа Биткойна или же на основе цифровых валют центрального банка (ЦВЦБ). В значительной степени это зависит от готовности экономических агентов к использованию виртуальных валют.Цель исследования —  изучение факторов, определяющих отношение экономических агентов к цифровым валютам и влияние финансовой грамотности на использование этих инструментов в качестве объекта инвестирования и средства платежа.Авторы использовали следующие методы: контент-анализ, ретроспективный анализ, межстрановой сравнительный анализ и эмпирическое исследование в форме онлайн-анкетирования студентов финансового профиля выпускных курсов. Представленное исследование является одним из первых, позволивших выявить различия в оценке своих знаний и готовности к использованию цифровых валют студентов финансового и нефинансового профиля, а также подтвердить более взвешенную оценку рисков и возможностей разных видов виртуальных валют при наличии у них финансовых знаний. Показано, что ситуация с принятием решений экономических агентов по вопросам использования криптовалют и ЦВЦБ существенно различается: в первом случае инициатива исходит от самих экономических агентов, принимающих решения на свой страх и риск, во втором —  экономические агенты ставятся перед фактом существования ЦВЦБ и необходимости их использования.Сделан вывод о том, что низкая финансово-цифровая грамотность населения может создать ментальный барьер для использования ЦВЦБ, осложнив их внедрение в национальных денежных системах. Отсутствие финансовой подготовки и низкая финансовая грамотность приводят к переоценке своих знаний участниками рынка криптовалют

PREREQUISITES FOR THE FORMATION OF D - ENANTIOMERS OF AMINO ACIDS OF ANIMAL PROTEINS IN THE MANUFACTURING PROCESS OF MEAT PRODUCTS

The paper presents studies on the presence or formation of d - enantiomers of amino acids in animal tissues or organs, in meat products during its production processes. It is shown that the process of epimerization of L - amino acid residues with the formation of D-enantiomers affect the reduction of the properties of food products, including the formation of oncoassociated subsequent effects on the human body.Modern control of the quantitative and qualitative composition of d-enantiomers of amino acids in food products, monitoring for stratification of the increased risk of toxic compounds in food are becoming an urgent medical and social problem. The studies planned in this paper are aimed at developing approaches to the creation of food products that reduce the oncogenic alimentary load on human health by solving the problem of technological modification of production, eliminating or minimizing post - translational modifications in proteins that contribute to the formation of d-enantiomers of amino acids. These studies will create a scientific and technological database associated with the risk assessment of carcinogenesis in protein matrices of animal origin. Based on the presented analysis, the task of developing and testing a method to control the accumulation of D-isomers in the course of various technological processes of meat production is extremely popular.The paper presents studies on the presence or formation of d - enantiomers of amino acids in animal tissues or organs, in meat products during its production processes. It is shown that the process of epimerization of L - amino acid residues with the formation of D-enantiomers affect the reduction of the properties of food products, including the formation of oncoassociated subsequent effects on the human body.Modern control of the quantitative and qualitative composition of d-enantiomers of amino acids in food products, monitoring for stratification of the increased risk of toxic compounds in food are becoming an urgent medical and social problem. The studies planned in this paper are aimed at developing approaches to the creation of food products that reduce the oncogenic alimentary load on human health by solving the problem of technological modification of production, eliminating or minimizing post - translational modifications in proteins that contribute to the formation of d-enantiomers of amino acids. These studies will create a scientific and technological database associated with the risk assessment of carcinogenesis in protein matrices of animal origin. Based on the presented analysis, the task of developing and testing a method to control the accumulation of D-isomers in the course of various technological processes of meat production is extremely popular

Features of biochemical blood analysis in children with cholelithiasis

The purpose of the study is to determine the features of biochemical blood analysis in children with cholelithiasis.Цель исследования – определить особенности биохимического анализа крови у детей с ЖКБ

Russian University Teachers’ Ethical Culture Regulation

Based on a review of publications of Russian and foreign researchers, the authors highlight the most significant topics on the deontology of university life. The article presents the results of an analysis of the texts of ethical codes of some leading universities in Russia (National Research University Higher School of Economics, Moscow State University, St. Petersburg State University, Kazan Federal University, Ural Federal University), as well as the results of an online survey (N = 297) of teachers of these universities. The survey was conducted to study the attitude of the teaching staff towards the tools for standardizing the moral culture of universities and the implementation of the values enshrined in the ethical standards of universities and ideals of academic community. Conclusions are made about the ethical attitudes of teachers and the effectiveness of moral regulation, as well as proposals for improving the ethical codes of universities are made

КВАНТОВО-КИНЕТИЧЕСКАЯ ТЕОРИЯ СОСТОЯНИЯ СМЕШАННОЙ ВАЛЕНТНОСТИ МЕТАЛЛИЧЕСКИХ ЦЕНТРОВ ПЕРОВСКИТОВЫХ СЕГНЕТОЭЛЕКТРИКОВ

Quantum-statistical description of coherent dipole-active states and quantum kinetic theory of mixed-valence state for metal centers of perovskite ferroelectrics is introduced. For layered perovskites with linear electron spectrum it allowed to establish a quadratic dependence of charge density distribution on momentum. It has been shown that a dipole polarization vector of resonance between d ( f )- and s ( p )-electron states becomes stable due to this found dependence.Предложены квантово-статистическое описание когерентных дипольно-активных состояний и квантово-кинетическая теория состояния смешанной валентности металлических центров перовскитовых сегнетоэлектриков. Для слоистых перовскитов с линейным электронным спектром это позволило установить квадратичную зависимость распределения зарядовой плотности от импульса и объяснить стабилизацию вектора дипольной поляризации резонанса между d ( f )- и s ( p )- электронными состояниями

Применение ботулинотерапии при постинсультной спастичности нижней конечности (клинические наблюдения)

The paper deals with the topical problem – the medical rehabilitation of patients with poststroke spasticity. It describes clinical cases of patients with poststroke spasticity of the upper and lower extremities who have received combined therapy using botulinum toxin type A (Botox) injections.Статья посвящена актуальной проблеме – медицинской реабилитации пациентов с постинсультной спастичностью. Приводятся клинические наблюдения пациентов с постинсультной спастичностью верхней и нижней конечности, получивших комбинированную терапию с применением инъекций ботулотоксина типа А (Ботокс)

EEG revealed improved vigilance regulation after stress exposure under Nx4: A randomized, placebo-controlled, double-blind, cross-over trial

ObjectivesVigilance is characterized by alertness and sustained attention. The hyper-vigilance states are indicators of stress experience in the resting brain. Neurexan (Nx4) has been shown to modulate the neuroendocrine stress response. Here, we hypothesized that the intake of Nx4 would alter brain vigilance states at rest.MethodIn this post-hoc analysis of the NEURIM study, EEG recordings of three, 12 min resting-state conditions in 39 healthy male volunteers were examined in a randomized, placebo-controlled, double-blind, cross-over clinical trial. EEG was recorded at three resting-state sessions: at baseline (RS0), after single-dose treatment with Nx4 or placebo (RS1), and subsequently after a psychosocial stress task (RS2). During each resting-state session, each 2-s segment of the consecutive EEG epochs was classified into one of seven different brain states along a wake-sleep continuum using the VIGALL 2.1 algorithm.ResultsIn the post-stress resting-state, subjects exhibited a hyper-stable vigilance regulation characterized by an increase in the mean vigilance level and by more rigidity in the higher vigilance states for a longer period of time. Importantly, Nx4-treated participants exhibited significantly lower mean vigilance level compared to placebo-treated ones. Also, Nx4- compared to placebo-treated participants spent comparably less time in higher vigilance states and more time in lower vigilance states in the post-stress resting-state.ConclusionStudy participants showed a significantly lower mean vigilance level in the post-stress resting-state condition and tended to stay longer in lower vigilance states after treatment with Nx4. These findings support the known stress attenuation effect of Nx4