96 research outputs found
Titanium compounds as catalysts of higher alpha-olefin-based super-high-molecular polymers synthesis
The synthesis of polymers of 10 million or more molecular weight is a difficult task even in a chemical lab. Higher α-olefin-based polymer agents of such kind have found a narrow but quite important niche, the reduction of drag in the turbulent flow of hydrocarbon fluids such as oil and oil-products. In its turn, searching for a catalytic system capable to produce molecules of such a high length and to synthesize polymers of a low molecular-mass distribution is part of a global task of obtaining a high-quality product. In this paper we had observed a number of industrial catalysts with respect to their suitability for higher poly-α- olefins synthesis. A number samples representing copolymers of 1-hexene with 1-decene obtained on a previous generation catalyst, a microsphere titanium chloride catalytic agent had been compared to samples synthesized using a titanium-magnesium catalyst both in solution and in a polymer medium
Synthesis and study of complexes of the novel Russian antiviral drug Camphecene with pentacyclic triterpenes of licorice
For the first time, the complexation of pentacyclic triterpenes of licorice (glycyrrhizic acid (GA) and its aglycone, glycyrrhetinic acid (GLA)) with the novel Russian antiviral drug Camphecene (Camph) was investigated. The complexes obtained at different molar ratios were studied using both UV/Vis spectroscopy and mass spectrometry (ESI MS). Formation of the host:guest complexes were registered: GA and GLA molecular complexes (Camph+2GA; Camph+2GLA) with stability constants К = 6.94 106 М-2 and К = 2.89 106 М-2, respectively. The research results demonstrate a considerable potential of ESI MS as a technique for simple and fast detection of formation of the complexes of GA /GLA and the novel drugs
Gerenciamento de projetos no comércio de livros na Rússia: barreiras e perspectivas de desenvolvimento
The development of book-selling industry is one of the sources for new economy development - knowledge economy. However, in modern Russian conditions of high crisis uncertainty, the book industry experiences serious difficulties, and the Russian book-selling network is declining every year. One of the anti-crisis measures for book-selling companies is the finding of some ways to improve project management at an enterprise. The purpose of the article is to identify the key barriers to the implementation of project management at the enterprises of the book-selling industry in Russia, as well as to determine the prospects of a project management system development in this area. The empirical base consists of study results conducted in 2018 at the enterprises of the Russian modern general-purpose bookstores of the book-selling industry.On the basis of the conducted research, they identified the main problems that Russian book-selling enterprises face when they implement project management: an insufficient formalization of project management processes; the uncertainty of project manager status caused by the lack of real powers; the lack of participant motivation system in project activities based on the results of an employee performance evaluation; low level of communication management and the lack of a clear interaction interface between various functional units and groups, etc. To minimize the likelihood of identified problems during project implementation, a special attention should be paid to the organization of a formalized management system (the creation of project offices), taking into account the interests of all project participants, clearly define the organizational structure and align management procedures, and use recognized methodology - project management standards that will facilitate the formation of a team focused on a particular result.El desarrollo de la industria de la venta de libros es una de las fuentes para el desarrollo de nuevas economías: la economía del conocimiento. Sin embargo, en las condiciones modernas rusas de alta incertidumbre de crisis, la industria del libro experimenta serias dificultades, y la red rusa de venta de libros disminuye cada año. Una de las medidas contra la crisis para las empresas vendedoras de libros es encontrar algunas formas de mejorar la gestión de proyectos en una empresa. El propósito del artículo es identificar las barreras clave para la implementación de la gestión de proyectos en las empresas de la industria de venta de libros en Rusia, así como determinar las perspectivas de desarrollo de un sistema de gestión de proyectos en esta área. La base empírica consiste en resultados de estudios realizados en 2018 en las empresas de las modernas librerías de propósito general rusas de la industria de la venta de libros.Sobre la base de la investigación realizada, identificaron los principales problemas que enfrentan las empresas rusas de venta de libros cuando implementan la gestión de proyectos: una formalización insuficiente de los procesos de gestión de proyectos; la incertidumbre del estatus de gerente de proyecto causada por la falta de poderes reales; la falta de un sistema de motivación de los participantes en las actividades del proyecto basado en los resultados de la nivel de gestión de la comunicación y la falta de una interfaz de interacción clara entre varias unidades funcionales y grupos, etc. Para minimizar la probabilidad de problemas identificados durante la implementación del proyecto, se debe prestar especial atención a la organización de un sistema de gestión formalizado (la creación de las oficinas de proyectos), teniendo en cuenta los intereses de todos los participantes del proyecto, definen claramente la estructura organizativa y alinean los procedimientos de gestión, y utilizan una metodología reconocida: normas de gestión de proyectos que facilitarán la formación de un equipo centrado en un resultado particular.O desenvolvimento da indústria de livros vendidos é uma das fontes para o desenvolvimento da nova economia - a economia do conhecimento. No entanto, nas condições russas modernas de alta incerteza de crise, a indústria de livros experimenta sérias dificuldades, e a rede russa de venda de livros está declinando a cada ano. Uma das medidas anti-crise para as empresas de venda de livros é a descoberta de algumas maneiras de melhorar o gerenciamento de projetos em uma empresa. O objetivo do artigo é identificar as principais barreiras para a implementação do gerenciamento de projetos nas empresas da indústria de vendas de livros na Rússia, bem como determinar as perspectivas de desenvolvimento de um sistema de gerenciamento de projetos nessa área. A base empírica consiste nos resultados do estudo realizado em 2018 nas empresas das modernas livrarias russas de uso geral da indústria de venda de livros.Com base na pesquisa realizada, eles identificaram os principais problemas que as empresas russas de venda de livros enfrentam quando implementam o gerenciamento de projetos: uma formalização insuficiente dos processos de gerenciamento de projetos; a incerteza do status do gerente de projetos causada pela falta de poderes reais; a falta de sistema de motivação dos participantes nas atividades do projeto com base nos resultados de uma avaliação de desempenho do funcionário; baixo nível de gerenciamento de comunicação e falta de uma interface de interação clara entre várias unidades funcionais e grupos, etc. Para minimizar a probabilidade de problemas identificados durante a implementação do projeto, uma atenção especial deve ser dada à organização de um sistema de gestão formalizado (a criação dos escritórios do projeto), levando em conta os interesses de todos os participantes do projeto, definir claramente a estrutura organizacional e alinhar procedimentos de gestão, e usar metodologia reconhecida - padrões de gerenciamento de projetos que facilitarão a formação de uma equipe focada em um resultado particular
Deep Learning for Spatiotemporal Anomaly Forecasting: A Case Study of Marine Heatwaves
Spatiotemporal data have unique properties and
require specific considerations. Forecasting spatiotemporal processes is a difficult task because
the data are high-dimensional, often are limited
in extent, and temporally correlated. Hence, we
propose to evaluate several deep learning-based
approaches that are relevant to spatiotemporal
anomaly forecasting. We will use marine heatwaves as a case study. Those are observed around
the world and have strong impacts on marine
ecosystems. The evaluated deep learning methods
will be integrated for the task of marine heatwave
prediction in order to overcome the limitations
of spatiotemporal data and improve data-driven
seasonal marine heatwave forecasts
Prediction of outcomes of cytomegalovirus infection of the initial few months of life
The research was based on the data of 155 newborns with manifestations of cytomegalovirus infection (CMV) appeared in the initial few months of life and on the results of the 7-years follow-up of this group of patients. While studying the courses and outcomes of CMV appeared in the initial few months of life in 155 patients of the tender age the disability is set for 22 (14,2 %) children. On the basis of discriminant analysis with the use of the most significant factors the model of prognosis of the outcomes of the carried infection was created in severe residual-organic disorders, dictating the necessity of determination of disability for children. This model can predict development of severe organ pathology in children of tender age after citomegalovirus infection appeared in the initial few months that will allow to select patients with high probability of disability and to realize for them individual rehabilitation measures to save their health in proper time
The results of follow-up study of children who had active cytomegalovirus infection during the first months of life
Follow-up observation of 44 patients who had cytomegalovirus infection (CMV) in the first months of life with the assessment of the health status of these children in terms was conducted during more than 7 years (control group consisted of healthy children). The study of course and outcomes of CMV infection of the first months of life showed that up to school period 43 % of patients had formed chronic pathology and 14,2 % of children at early age formed group of "children with disability". The structure formed chronic pathology up to school period in almost all parameters values. In main group central nervous system pathology occurred 4 times more often (р < 0,001), allergy - 3 times more often (p = 0,05), the pathology of the cardiovascular system - 3 times more often, endocrine pathology - 3 times more often, pathology of gastrointestinal tract and hepatobiliary system - 5 times more often
AGE OF THE KINTEREP FORMATION OF THE NORTHWESTERN SALAIR: CHEMOSTRATIGRAPHY AND U-Pb ZIRCON DATING
A comprehensive study of the stratotype section of the Kinterep formation of the North-Western Salair was carried out, including geochemical and isotope (Sr, C, O) studies of carbonate rocks, and U-Pb dating (LA-ICP-MS) of igneous zircon crystals from tuffites. The studied carbonate rocks are pure limestones with Mg/Ca less than 0.007 and a low proportion of insoluble residue (average 5 %). Kinterep limestones are characterized by δ18OSMOW values from 19.8 to 23.8 ‰ and δ13СPDB values from –0.7 to +0.9. The Sr isotope composition in limestones of the Kinterep formation varies in a narrow range of 87Sr/86Sr values between 0.70851 and 0.70859. Comparison of the obtained isotopic characteristics (87Sr/86Sr and δ13СPDB) of Kinterep formation limestones with the generalized global 87Sr/86Sr variation curve and δ13СPDB values in the pale-ocean suggests two equally probable interpretations of the time of accumulation of Kinterep formation limestones: 550–540 and 525–510 Ma. U-Pb dating of magmatic zircon crystals from tuffite, which forms an interlayer among limestones of the Kinterep formation, showed the age at the boundary of ~515 Ma. Thus, using a combination of isotope (Sr, C) chemostratigraphy of carbonate rocks and U-Pb dating of igneous zircon crystals from tuffites syngenetic to limestones, the age limit of 525–510 Ma was established for the time of the formation of the Kinterep formation of the Salair basin. Carbonate rocks of similar age and similar features of the isotopic composition are known in neighbouring areas (for example, the Kuznetsk Alatau) and in regions of the Siberian Platform and microcontinents of Central Asia (Tuva-Mongolian and Dzabkhan) spatially distant from the Salair basin
Relationships between the allozyme and phenotypic diversities of Picea ajanensis populations
The structures of Picea ajanensis populations were compared based on allozyme analysis of vegetative buds and morphometric analysis of generative organs. Six cenopopulations of P. ajanensis were investigated in areas with various levels of volcanic impact in the Kamchatka Peninsula. The genetic structures of spruce populations and phenotypes were determined by analysis of ten enzyme systems (PGM, GOT, HK, LAP, MDH, SKDH, IDH, GDH, PGI and SOD). Phenotypic variability of spruce populations was estimated based on the composition of morphotypes that were identified by using geometric morphometrics of cone-scale shapes. Pairwise comparison of samples of cones from 170 trees from six populations revealed 12 morphotypes differing in the shape of cone scales. Comparative assessment of variability and similarity of populations was carried out based on the frequency of occurrence of phenotypes and frequency of alleles of polymorphic loci. Correlations of the genetic and phenotypic distance matrices between different phenotypes were revealed. This observation was consistent with the genetic determination of the shape of cone scales in spruce. Genetic differences between the morphotypes with regard to nine polymorphic loci (Got-2, Skdh-1, Idh-2, Pgm-2, Mdh-1, Mdh-3, Pgm- 1, Pgi-2, and Hk) were not significant. Statistically significant differences between the morphotypes were revealed for two loci: Pgm-2 and Mdh-1. Differences in the genetic diversity of spruce populations generally corresponded to differences in their phenotypic diversity. The high levels of genetic and phenotypic diversity characterized a stable population structure of spruce in the area of weak volcanic influence. Changes in the genetic structure and low levels of the phenotypic diversity of spruce were observed under catastrophic volcanic impact
Monitoring of respiratory viral infections in Moscow during 2011–2022
Introduction. Respiratory viruses (RV) circulate throughout the world and in all seasons of the year. Long-term monitoring of the distribution of respiratory pathogens is necessary to analyze the relevance of diagnostic systems to current viral isolates, to assess the risks of infection and the need for vaccine development and use, as well as to investigate the interdependence of RV reproduction in mixed infections.
Objective — to study the causative agents of acute respiratory viral infections (ARVI) in Moscow during 2011–2022 by reverse transcription with subsequent polymerase chain reaction with fluorescent hydrolysis probes detection in real-time (RT2-PCR).
Materials and Methods. Nasopharyngeal swabs from 3908 patients with acute respiratory infections were examined by the RT2-PCR.
Results. Monitoring of RV spread in Moscow showed cyclical changes in frequencies with three dominant species: influenza A virus (up to 31.3%), respiratory syncytial virus (up to 24.8%) and human rhinoviruses (up to 21.3%) in 2011–2020. The increase in the portion of unidentified clinical specimens from 1.2 to 28.5% in 2022 indicated incomplete accordance of diagnostic systems to modern RV isolates or the emergence of new species or strains of pathogens. Unidirectional changes in dynamics were registered for 5 out of 9 studied RVs with correlation coefficients of 0.43–0.79. High frequencies of mixed acute respiratory viral infections (up to 33.4%) along with unidentified samples do not allow us to accurately assess the risks of infection with various RV in Moscow, but prove the necessity of preventing infectious diseases with the most common RV.
Conclusion. Analysis of the dynamics of RV frequencies in Moscow showed the preservation of the dominant species: influenza A virus, respiratory syncytial virus and human rhinoviruses. During the period of vaccination against COVID-19, the proportion of seasonal coronaviruses increased
Synthesis and study of complexes of the novel Russian antiviral drug Camphecene with Plant’s Flavonoids
Received: 01.03.2021. Revised: 22.04.2021. Accepted: 27.04.2021. Available online: 28.04.2021.The authors are grateful to the Corresponding Member of the RAS, Doctor of Chemical Sciences, Professor of NIOCH SB RAS Salakhutdinov N.F. for the kindly provided scaffold monoterpenoid Camphecene.Traditionally, glycyrrhizic acid has been used to form polydentate complexes. For the first time in the presented paper, the complexation of the Plant’s Flavonoids (Quercetin (Qu) and its glycoside - Rutin (Rut)) with the novel Russian antiviral drug Camphecene (Camph) was investigated. The complexes obtained at different molar ratios were studied using UV/Vis spectroscopy. Formation of the host: guest complexes were registered: Qu and Rut molecular complexes (Camph+2Qu; Camph+2Rut) with a stability constant K = 3.3·108 M-2. Comparison of the binding constants of the obtained complexes shows that the efficiency of Camphecene complexation with the participation of flavonoids is more efficient than with the participation of triterpenoids. Besides, it was found that the complexes of Camphecene with the quercetin and rutin are soluble in water, in contrast to the complexes with triterpenoids, which makes it possible to increase the bioavailability of both Camphecene and flavonoids. The obtained results demonstrate the high potential of flavonoids Qu and Rut to the development of novel pharmaceutical forms using the example of Camphecene in the form of molecular complexes, as the novel forms of delivery.This work was supported by the Ministry of Science and Higher Education of the Russian Federation (State assignment in the field of scientific activity, project No 0852-2020-0031) and the Russian Foundation for Basic Research (RFBR, grant no. 19-33-90211-Aspiranty)
- …