964 research outputs found
Formation of oxide layers on aluminum, niobium, and tantalum in molten alkali metal carbonates
The electrochemical synthesis of niobium, tantalum, and aluminum oxide nanolayers is studied in the melt of lithium, sodium, and potassium carbonates with various additives to a salt phase in an oxidizing atmosphere at a temperature of 773 and 873 K. A scheme is proposed for high-temperature anion local activation of the process. © 2013 Pleiades Publishing, Ltd
Safety profile of paediatric COVID-19 vaccines: An analysis of the US Vaccine Adverse Event Reporting System
Aim: To provide further evidence on the safety profile of COVID-19 vaccines in paediatrics by analysing the spontaneous reports of adverse effects related to these vaccines.Methods: Reports related to US paediatric population (from 0 to 17 years) vaccinated with authorised COVID-19 vaccines were extracted from Vaccine Adverse Event Reporting System from December 2020 to 17 November 2022. We conducted a descriptive analysis of Adverse Events Following Immunization (AEFI), calculating reporting rate of serious AEFIs and focusing on myocarditis and Guillain-Barre Syndrome after mRNA COVID-19 vaccines.Results: Overall, 52 720 reports were retrieved: 77% (40541)-Pfizer-BioNTech, 19% (10083)-Moderna, a small proportion for other vaccines 4% (2096). Most of AEFIs were non-serious and listed in corresponding SPCs. Of serious AEFIs, 96% were related to the Pfizer-BioNTech vaccine. Roughly 91% (47874) were related to people from 6 to 17 years, a small percentage of 9% (4773) to the younger group (0-5 years). In both groups, most of the reports were related to mRNA vaccines and the percentage of AEFIs experienced by females were similar to males.Conclusions: Data showed that events most frequently reported were non-serious and listed in the corresponding SPCs, extending the evidence of safety of COVID-19 vaccines authorised in the United States in children
Citation of Mass Media Resources in Social Network
The role of social networks in the formation of collective behaviour and a
sustainable point of view/position regarding the information events or facts is
studied herein. The purpose of the study is to analyse the reaction of the users of
popular social networks, expressed in quotations and responses to the messages
of mass media resources. A statistical measure of interest in the media news is
identified through unique messages from queries on the topic. The approach
used is aimed at improving the scientific argumentation on the assumption of a
direct relationship between these phenomena. The empirical evaluation is carried
out according to the data obtained from the Russian segment of social networks.
The trends in the distribution of media content in social media and social networks
are revealed using structural and correlation analysis. It is determined that the
publications in online media correlate directly with the activities of social networks
and are caused by the release of one or another information event. The results of
the study also convincingly point out that the importance of the media resources,
expanding due to the integration of social networks, increases, while the classical
model of online media (media edition as own website) is gradually losing
popularity and audience
Assessment of Women’s Early-stage Entrepreneurial Activity in 2018
The analysis of the regularities characterizing the existing rate of female early-stage entrepreneurial activity, as well as the identification of reserves for female entrepreneurship growth is relevant nowadays. The purpose of the work is to assess the rates of entrepreneurial activity of women, their motivational preferences, and comparative analysis of female and male early-stage entrepreneurial activities. The study is based on the economic analysis of the data on 48 countries, presented in the Global Entrepreneurship Monitor report for 2018. Normal distribution density functions are used in the modeling process. The research reveals features of female entrepreneurship and the barriers to its development. The paper defines countries with high and low values of the considered indicators. The study estimates the existing rates of opportunity and necessity motivation of female entrepreneurs, presents the analysis of the ratio of female to male participation in early- stage entrepreneurial activity, and proves the hypothesis on substantial differentiation of these indicators across countries. The obtained knowledge can be used in future scientific research, in the educational process of bachelors and masters training. The scientific novelty lies in the study of the distribution of indicators characterizing female entrepreneurs’ motivation and the existing gender gap in early-stage entrepreneurship. The study proposes new methods and tools for the analysis and presents a comparative analysis of the development of female and male early-stage entrepreneurship
Features of micro- and ultrastructure of low-fat butter and its low-fat analogues
The aim of the research was to study the features of the structure of low-fat butter and butter pastes, which, in terms of composition and properties, more fully meet the requirements of a healthy diet than high-fat types of butter. The objects of research were: butter with fat content of 72.5%; butter with fat content of 55% made with the addition of skimmed milk powder; butter of the same fat content with the addition of stabilizers based on guar and xanthan gums and emulsifiers based on monoand diglycerides of fatty acids; butter pastes with fat content of 45% with similar additives used to increase the stability of the process of butter formation and improve the texture. The microstructure was studied using an MBI-6 microscope, and the ultramicrostructure was studied using a Phillips electron microscope. In the first case, the sample was prepared by crushing the sample, in the second one — by the method of ultrafast freeze-fracture and etching. Researches have shown that the use of the introduced ingredients improves the homogeneity of the structure of the studied products. Due to the ability of milk proteins and stabilizers to retain moisture, it is more evenly distributed and well retained in the fat matrix of the product, formed from crystalline and liquid fat in the form of a continuous phase, which is confirmed by a sufficient penetration depth of the fat-soluble dye. Plasma droplets in butter with fat content of 72.5% and 55% are more isolated than in butter pastes, as indicated by the greater penetration depth of the water-soluble dye. The average diameter of isolated moisture droplets in low-fat products was 3.3–5.4 μm, and the average diameter of the fat globules that form the basis of the crystalline framework was 5.4–7.4 μm, depending on the composition of the product. For butter with fat content of 72.5%, the values of these indicators were 2.8 and 4.0 μm. The results of the study indicate the presence of differences in the sizes of structural elements, but at the same time confirm the uniformity of the structure of low-fat products, allowing them to be attributed to dispersions «water-in-oil»
The possibility of administration of glutamate receptors antagonists in the treatment of parkinson's disease
Parkinson's disease is the slow-progressing chronic neurodegenerative disease. Modern medicine has not yet found methods of curing disease, however, the existing methods of conservative and surgical treatment significantly improve the patient’s quality of life and slow the progression of the diseas
Социальная активность современной молодежи: экологический аспект
This article deals with the problems of development of social activity of youth. Identified and justified the need for the development of environmental competence. The definition of environmental social activity. On the basis of the studyrevealed the main areas of the environmental activities of today's youthВ статье рассмотрены проблемы развития социальной активности молодежи. Выявлена и обоснована необходимость развития экологической компетентности. Дано определение экологической социальной активности. На основе проведенного исследования выявлены основные направления экологической деятельности современной молодеж
Dimethyl 11,13-dimethyl-16-[1,2-bis(methoxycarbonyl)ethenyl]-12-oxo-16,17-dioxa-18-azahexacyclo[7.5.1.11,4.16,9.110,14.05,15]octadeca-2,7-diene-2,3-dicarboxylate
The title compound, C27H29NO11, is a product of the tandem ‘domino’ Diels–Alder reaction. The molecule comprises a fused hexacyclic system containing four five-membered rings (two dihydrofuran and two tetrahydrofuran) in the usual envelope conformations and two six-membered rings (tetrahydropyridinone and piperidine) adopting slightly flattened boat and chair conformations, respectively. The dispositions of the carboxylate substituents relative to each other are determined by both steric reasons and intermolecular C—H⋯O hydrogen bonding and attractive antiparallel C=O⋯C=O interactions [C⋯O = 2.995 (2) Å]
Automated system for diagnosing craniocerebral injury
A Russian national computing and communication system designed to assist non-specialized physicians in the diagnosis and treatment of craniocerebral injury is described
Methyl 4,5-diacetoxy-1-oxo-2-phenylperhydro-4,6-epoxycyclopenta[c]pyridine-7-carboxylate ethanol solvate
The title compound, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as an ethanol monosolvate, C20H21NO8·C2H6O. The title molecule comprises a fused tricyclic system containing two five-membered rings (cyclopentane and tetrahydrofuran) in the usual envelope conformations and one six-membered ring (piperidinone) adopting a flattened twist–boat conformation
- …