26 research outputs found

    C60-dyad aggregates: self-organized structures in aqueous solutions

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    Extensive full-atomistic molecular dynamics simulations are performed to study the self-organization of C60-fullerene dyad molecules in water, namely phenyl-C61-butyric acid methyl ester and fulleropyrrolidines, which have two elements of ordering, the hydrophobic fullerene cage and the hydrophilic/ionic group. While pristine fullerene or phenyl-C61-butyric acid methyl ester forms spherical droplets in order to minimize the surface tension, the amphiphilic nature of charged solute molecules leads to the formation of supramolecular assemblies having cylindrical shape driven by charge repulsion between the ionic groups located on the surface of the aggregates. We show that formation of non-spherical micelles is the geometrical consequence if the fullerene derivatives are considered as surfactants where the ionized groups are only hydrophilic unit. The agglomeration behavior of fullerenes is evaluated by determining sizes of the clusters, solvent accessible surface areas, and shape parameters. By changing the size of the counterions from chloride over iodide to perchlorate we find a thickening of the cylinder-like structures which can be explained by stronger condensation of larger ions and thus partial screening of the charge repulsion on the cluster surface. The reason for the size dependence of counterion condensation is the formation of a stronger hydration shell in case of small ions which in turn are repelled from the fullerene aggregates. Simulations are also in good agreement with the experimentally observed morphologies of decorated C60-nanoparticles

    Water around fullerene shape amphiphiles: a molecular dynamics simulation study of hydrophobic hydration

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    Fullerene C60 sub-colloidal particle with diameter ∼1 nm represents a boundary case between small and large hydrophobic solutes on the length scale of hydrophobic hydration. In the present paper, a molecular dynamics simulation is performed to investigate this complex phenomenon for bare C60 fullerene and its amphiphilic/charged derivatives, so called shape amphiphiles. Since most of the unique properties of water originate from the pattern of hydrogen bond network and its dynamics, spatial, and orientational aspects of water in solvation shells around the solute surface having hydrophilic and hydrophobic regions are analyzed. Dynamical properties such as translational-rotational mobility, reorientational correlation and occupation time correlation functions of water molecules, and diffusion coefficients are also calculated. Slower dynamics of solvent molecules - water retardation - in the vicinity of the solutes is observed. Both the topological properties of hydrogen bond pattern and the "dangling" -OH groups that represent surface defects in water network are monitored. The fraction of such defect structures is increased near the hydrophobic cap of fullerenes. Some "dry" regions of C60 are observed which can be considered as signatures of surface dewetting. In an effort to provide molecular level insight into the thermodynamics of hydration, the free energy of solvation is determined for a family of fullerene particles using thermodynamic integration technique

    Reference materials of catalytic activity as a means of ensuring the metrological traceability of measurement results. KATAL

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    Introduction. The article considers the problems of metrological support of catalytic activity measurements. The paper gives certain characteristics of the State Primary Special Measurement Standard for the unit of catalytic activity – KATAL and examines the role of reference materials (RMs) in ensuring the metrological traceability of measurement results.Materials and methods. A method for measuring the concentration of the recombinant protective antigen of Bacillus anthracis and the recombinant GP-protein of the Ebola virus, which means in using «sandwich» enzyme-linked immunosorbent assay, was certified by FGUP «VNIIMS» as a measurement procedure. The following RMs tested by FGUP «VNIIMS» can be used for the development and production of appropriate control samples when performing measurements for comparisons: the RM for the mass concentration of the recombinant protective antigen of Bacillus anthracis in phosphate-saline solution, the RM for the mass concentration of the recombinant GP-protein of the Ebola virus, and the RM for the mass concentration of recombinant Clostridium Difficile toxin.Results. The paper presents the main reactions of the method for measuring the catalytic activity of catalysts for heterogeneous processes, which are also used to carry out exhaust gas cleaning processes.Discussion and conclusions. Thus, conditions have been created for building hierarchies of calibrations of in-demand objects established on the basis of the List of Critical Technologies of the Russian Federation, state programs for the development of industrial sectors

    Assessment of the psycho-emotional state of patients after COVID-19-associated pneumonia in relationship with laboratory indicators

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    The aim. To study peculiarities and association of psychological and laboratory indicators in patients with cardiovascular diseases (CVD) who underwent COVID-19 to clarify the factors affecting the possibility of developing delayed psychological and cardiovascular adverse events.Methods. The study enrolled 350 patients with COVID-19. Group 1 consisted of 92 patients without CVD, Group 2 – of 258 patients with CVD. Indicators of laboratory and psychological parameters were assessed according to the data of psychological questionnaire using GAD-7 (General Anxiety Disorder-7), PHQ-9 (Patient Health Questionnaire-9), PSS (Perceived Stress Scale) screening scales and SF-36. Parameters of complete blood count and biochemical blood tests were measured during hospitalization and three months after discharge from the monohospital.Results. After three months, in the general group of patients, signs of anxiety and depression were detected in more than 30 % of the examined patients, signs of stress – in 10.4 %. In the group with CVD, psycho-emotional disorders were identified in 1/4 of the patients, and severe stress – in 8 % of those included in the study. In addition, it was registered that the indicators of erythrocyte sedimentation rate, fibrinogen, high-sensitivity C-reactive protein (CRP), homocysteine and IL-6 remained at a higher level in the second group.Correlation analysis showed that the psychological component of health is interconnected with the level of neutrophils (p = 0.044) and fibrinogen (p = 0.050); the physical component of health is correlated with the level of erythrocytes (p = 0.030), hemoglobin (p = 0.015), CRP (p = 0.002), creatine phosphokinase (p = 0.036) and glucose (p = 0.017). Regression analysis revealed that in patients with CVD three months after hospitalization, an increased glucose index contributes to deterioration, and increased hematocrit and mean hemoglobin concentration improve the quality of life of patients.Conclusion. Laboratory markers that maintain the duration of a prolonged vascular reaction, violation of the rheological and metabolic properties of blood, determine the nature of the development of both psychological and cardiovascular complications

    Стандартные образцы каталитической активности как средство обеспечения метрологической прослеживаемости результатов измерений. КАТАЛ

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    Introduction. The article considers the problems of metrological support of catalytic activity measurements. The paper gives certain characteristics of the State Primary Special Measurement Standard for the unit of catalytic activity – KATAL and examines the role of reference materials (RMs) in ensuring the metrological traceability of measurement results.Materials and methods. A method for measuring the concentration of the recombinant protective antigen of Bacillus anthracis and the recombinant GP-protein of the Ebola virus, which means in using «sandwich» enzyme-linked immunosorbent assay, was certified by FGUP «VNIIMS» as a measurement procedure. The following RMs tested by FGUP «VNIIMS» can be used for the development and production of appropriate control samples when performing measurements for comparisons: the RM for the mass concentration of the recombinant protective antigen of Bacillus anthracis in phosphate-saline solution, the RM for the mass concentration of the recombinant GP-protein of the Ebola virus, and the RM for the mass concentration of recombinant Clostridium Difficile toxin.Results. The paper presents the main reactions of the method for measuring the catalytic activity of catalysts for heterogeneous processes, which are also used to carry out exhaust gas cleaning processes.Discussion and conclusions. Thus, conditions have been created for building hierarchies of calibrations of in-demand objects established on the basis of the List of Critical Technologies of the Russian Federation, state programs for the development of industrial sectors.Введение. В данной статье рассматриваются вопросы метрологического обеспечения измерений каталитический активности. Приведены характеристики Государственного первичного специального эталона единицы каталитической активности – КАТАЛ. Рассмотрена роль стандартных образцов в обеспечении метрологической прослеживаемости результатов измерений.Материалы и методы. Метод измерений концентрации рекомбинантного протективного антигена Bacillus anthracis и рекомбинантного белка GP вируса Эбола, заключающийся в использовании «сэндвич» варианта иммуноферментного анализа, аттестован ФГУП «ВНИИМС» в качестве методики измерений. Испытанные ФГУП «ВНИИМС» стандартные образцы массовой концентрации рекомбинантного протективного антигена Bacillus anthracis в фосфатно-солевом растворе, массовой концентрации рекомбинантного белка GP вируса Эбола и массовой концентрации рекомбинантного токсина Clostridium Difficile могут применяться для разработки и производства соответствующих контрольных образцов, при проведении измерений для сличений.Результаты исследования. Приведены основные реакции метода измерений каталитической активности катализаторов гетерогенных процессов, которые применяются и для осуществления процессов очистки выхлопных газов.Обсуждения и заключения. Таким образом, созданы условия для построения иерархий калибровок востребованных объектов, установленных на основе Перечня критических технологий Российской Федерации, государственных программ развития отраслей промышленности

    Organization of nanoparticles at the polymer brush-solvent interface

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    We investigate the organization of nanosized particles in a polymer brush by DPD simulations. The brush is composed of flexible chains grafted by one end to a solid substrate. The polymer-insoluble nanoparticles are treated as rather rigid aggregates of almost spherical form. Varying either the strength of interaction between polymer and nanoparticle beads or the concentration of nanoparticles (i.e., the load by nanoparticles) we observe particle cluster formation in the distal brush region. For low load, in agreement with theoretical predictions we demonstrate that the nanodroplet formed is vertically oriented and exhibits cylinder shape. With increasing concentration the aggregate at the rim of the brush becomes a flattened sphere. For high load, when the droplet-droplet interaction is significant, the cluster becomes highly anisotropic and the horizontally oriented nanodroplet adopts a cylinder (or baguette-like) shape

    About the Master’s Program “Creative Personnel Management”: Methodological Foundations

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    In order to improve the training of masters majoring in “Personnel Management”, a sociological study of the opinions of employers was carried out. Based on the results of the study, HRtechnologies were clarified and the content of professional competencies, which should be possessed by specialists in HRM departments of organizations and enterprises who belong to the category of creative personnel, was disclosed. The main driving force behind the growth of innovative economies of developed and developing countries is a social group of people characterized by a high level of education, creative abilities and entrepreneurial behavior skills. This social group is called the “creative class”. The general criteria for classifying employees as creative personnel are defined. At the preliminary stage of the study, the Federal State Educational Standard of Higher Education 38.04.03 “Personnel Management (Master’s level)” was analyzed as well as the requirements of a professional standard for a HRM specialist. To study the opinions of employers, a two-stage study was carried out. At the first stage, a focused interview with senior management staff was carried out in order to find out the practical methods of working with creative staff (N = 43). The working hypothesis was the assumption that there is a significant specificity in the processes of attracting, developing and retaining creative staff. The results of the processing of interview texts are presented. Based on the interview, a list of professional competencies was prepared, the possession of them can improve the quality of creative staff management. At the second stage, a questionnaire survey was conducted among a wider group of employers with the task of determining the priority of the proposed professional competencies (N=87). Interviews and questionnaires were conducted with representatives of human resources and the management team of enterprises and organizations (including higher education institutions) of Nizhny Novgorod, whose main activity is aimed at obtaining an intellectual product. Two senior employees of one of the largest startups in Silicon Valley (USA) were among the interviewees. The authors, with the support of the Vladimir Potanin Scholarship Program, have developed a master’s program in Creative Human Resources Management. Based on the results of the study, appropriate adjustments were made to the work programs of the disciplines and to the list of professional competencies of the developed master’s program, which determine its orientation

    The Development of the University’s Organizational Culture as a Tool to Increase its Competitive Advantages

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    Исследовательская статья посвящена изучению организационной культуры университета. Для того чтобы выжить и быть конкурентоспособным в условиях глобальной конкуренции на международном и всероссийском уровнях, вуз должен обладать уникальной ценностью по сравнению с другими. Одним из стратегических источников формирования конкурентных преимуществ вуза является изменение его организационной культуры. Именно ее развитие позволяет сформировать новые ценностные установки, как у преподавателей, так и у студентов. В статье проведено исследование организационной культуры Национального исследовательского Мордовского государственного университета им. Н. П. Огарева. Для исследования поверхностного уровня организационной культуры вуза нами было изучено отношение преподавателей и студентов к ключевым элементам организационной среды вуза (традиции, корпоративный стиль, поощрения и наказания и т. д.). Анализ подповерхностного уровня организационной культуры осуществлялся с использованием адаптированных вариантов вопросников К. Камерона и Р. Куина. Базовые ценностные суждения были идентифицированы с помощью применения методики Г. Ховстеде. Число респондентов, принявших участие в исследовании, составило 847 человек, из которых 100 человек – это научно-педагогические работники, 747 – студенты. Результаты исследования представлений профессорско-преподавательского состава и студенчества об организационной культуре позволили получить общее видение о ключевых ценностно-культурных ориентирах и идентифицировать сложившуюся организационную культуру. Исследование показало наличие фрагментарного восприятия элементов культуры представителями разных подразделений, имеющих иногда диаметрально противоположную оценку ее параметров. В связи с этим необходимо проведение ряда обучающих программ, направленных на развитие системы коммуникаций, организационных ценностей, психологического комфорта и корпоративного имиджа. При этом процесс развития выделенных компонентов считаем целесообразным рассматривать через призму реализации определенных целей, что обеспечит качество всех протекающих в университете организационных процессов, а, следовательно, и повышение его конкурентных преимуществ.The research article is devoted to studying the university’s organizational culture. To survive and be competitive in the face of strong national and international competition, the university has to be unique as compared to other universities. One of the strategic sources for forming a university’s competitive advantages is to change its organizational culture. It is the university’s development that makes it possible to form new value attitudes, both among teachers and students. The article observes a study of the organizational culture in National Research Mordovia State University. To analyse the surface level of the organizational culture of the university, we have investigated the attitude of teachers and students to the key elements of the organizational environment of the university (tradition, corporate style, encouragement and punishment etc.). The analysis of the subsurface level of the organizational culture has been carried out with the help of adapted versions of K. Cameron and R. Quinn’s questionnaires. Basic value judgments are identified by means of G. Hofstede’s method. The respondents of the questionnaires have numbered 847, including 100 research and teaching staff and 747 students. The results of studying the teachers’ and students’ views on organizational culture provide the general idea of key values, culture orientations, which identify the whole of this culture. The study shows the fragmentary perception of culture elements by the representatives of different departments, which sometimes leads to a diametrically opposite assessment of the parameters of this culture. In this regard, it is necessary to implement a number of training programs aimed at developing the communication system, organizational values, psychological comfort, and corporate image. At the same time, it seems reasonable to consider the development process of the selected components through achieving certain goals, which must ensure the quality of all organizational processes within the university, and, consequently, increase its competitive advantages
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