Normalized difference vegetation index for desiccation evaluation with glyphosate + 2,4-D in magnetized spray solution

Water magnetization and geoprocessing are increasingly utilized tools in weed management. Our objective was to study the influence of water magnetization on herbicide efficiency and to verify whether there is a relationship between control scores and the normalized difference vegetation index (NDVI). In the laboratory experiment, water was subjected to magnetization and evaluated with respect to four characteristics. In the field experiment, plots of Brachiaria grass were subjected to treatments in a factorial scheme (6 × 2 + 1). Six herbicidal factors (doses of glyphosate and glyphosate + 2,4-D) and the magnetization or absence of magnetization of the spray solution were evaluated and compared against the control treatment (without spraying). Weed control assessments were carried out six times. Images were obtained using an embedded multispectral camera to determine the NDVI values. Data related to water characteristics were analyzed using the t test. Weed control and NDVI data were subjected to analysis of variance and are presented in regression graphs. Dispersion analysis of NDVI data was performed according to the control scores. The magnetization process decreased the pH of the water and increased the surface tension, but it did not influence the control scores or the NDVI. As the glyphosate dose was increased, the control scores were higher and the NDVI values were lower. Magnetized water did not affect the biological efficiency of the herbicides, and there was a strong correlation between the control scores and the NDVI values.

Age-related changes in the viscoelasticity of rabbit lens characterised by surface wave dispersion analysis

The viscoelastic properties of the young and mature rabbit lenses in situ are evaluated using wave-based optical coherence elastography (OCE). Surface waves in the crystalline lens are generated using acoustic radiation force (ARF) focused inside the eyeball. Surface-wave dispersion is measured with a phase-stabilised optical coherence tomography (OCT) system. The Young's modulus and shear viscosity coefficient are quantified based on a Scholte wave model. The results show that both elasticity and viscosity are significantly different between the young and mature lenses. The Young's modulus of the lenses increased with age from 7.74 ± 1.56 kPa (young) to 15.15 ± 4.52 kPa (mature), and the shear viscosity coefficient increased from 0.55 ± 0.04 Pa s (young) and 0.86 ± 0.13 Pa s (mature). It is shown that the combination of ARF excitation, OCE imaging, and dispersion analysis enables nondestructive quantification of lenticular viscoelasticity in situ and shows promise for in vivo applications.

SPACECRAFT RELIABILITY CALCULATIONS USING STATISTICAL REGULARITIES IN OCCURRENCES OF FAILURES IN DEVICES, UNITS AND ASSEMBLIES DURING THEIR OPERATION

The paper addresses reliability analysis of manned spacecraft with the use of statistical regularities in in-flight failures of their devices, units and assemblies. It formulates validity criteria for using a device failure in reliability analysis, proposes a method for analyzing and classifying failures which enables factoring in different types of failures in reliability analyses. It considers a hypothesis of the absence of statistically significant differences in probabilities of individual valid failures and demonstrates the feasibility of its adoption with the use of dispersion analysis. A method is developed for evaluating product reliability using a functional relationship between reliability and the number of failures occurring in flight which makes it possible to significantly simplify reliability analysis for complex products, to establish the number of in-flight failures that is acceptable from the standpoint of the product reliability requirements, to study various product architectures from the standpoint of reliability criteria. It proposes a method for evaluating the lower boundary for the probability of manned spacecraft completing their missions based on the failure modes, effects and criticality analysis, and demonstrates the feasibility of optimizing the product redundancy scheme based on the fault tolerance requirements. Key words: manned spacecraft, flight, failure, fault tolerance, classification of failures, reliability, probability of failure-free operation, statistical analysis, dispersion analysis.

Influence of agrochemical agents on biometric parameters of pear varieties in protected soil conditions

The article presents data on the study of the effect of foliar treatment with the mineral fertilizer «Idrofloral brand 14-11-22+8CaO» and the growth regulator «Stimoros» on the biometric parameters of pear seedlings with a closed root system in protected soil conditions. The research was conducted in 2018-2020 in the Orenburg branch of the Federal Horticultural Research Center for Breeding, Agrotechnology and Nursery. The objects of research were pear varieties of the summer ripening period Lada and Chizhovskaya. The seedlings were obtained by winter inoculation in the third decade of December. The drugs were used three times: 1st processing in the phase of the 5th present sheet, then 2 times with an interval of 10 days. The studied concentrations of non-root top dressing were determined according to the instructions for them. Biometric observations of seedlings were carried out according to the following parameters: seedling height (cm), number (pcs.) and leaf area (cm2 ). Mathematical processing of experimental data was carried out using the dispersion analysis according to B. A. Dospekhov. As a result of the conducted studies, the positive effect of these drugs on the growth and development of pear plants, different depending on the variety, was revealed. The greatest effectiveness on the Chizhovskaya variety was shown by the use of the mineral fertilizer «Idrofloral brand 14-11-22+8CaO» with a rate of application of 3.75 g/l, which contributed to an increase in the length of vegetative growth by an average of 45.6 %, the number of leaves — by 33.7 %, the foliage of seedlings-by 40.0 % compared to the control, thereby having a positive effect on the processes of formation and development of the leaf apparatus. In the Lada variety, the best results were noted when using the drug «Stimoros» at a dosage of 0.94 ml/l: the growth parameters of seedlings increased by 18.4 %, the number of leaves — by 12.1 %.

PROFILE OF THE ORGANIZATIONAL CULTURE IN YOUTH CLUB FOOTBALL (THE PRESENT SITUATION IN BLAGOEVGRAD REGION)

The end of the crisis in Bulgarian football is discussed through the perspective of solving the problems in youth football. Although organizational culture is essential for effectiveness within organizations, few studies are related to the organizational culture in (youth) football clubs in Bulgaria. The article aims at studying the organizational culture in three clubs from the Youth-17 League in the South-West Bulgaria Zone 1 and Zone 2. 60 players and 3 coaches participated in a survey conducted through OCAI (Cameron and Quinn). The weight of certain factors considered important for achievement in clubs was measured through dispersion analysis. The hierarchy and clan types are predominant in the club’s profiles. According to the analysis, the present state is characterized by fewer distractions than the desired state. ANOVA shows that the team success factor has the strongest influence regarding the differentiation of the clan (present state) and market (desired state) types of cultures. The competing experience factor has a lesser effect and differentiates the market and the adhocracy type of cultures (the desired state). The prospect factor differentiates between the clan and market type in the desired state. Both groups surveyed have similar preferences for the types of organizational culture in the teams, with the “strength” of the preference criteria having higher value with the coaches. The typical team sport profile of organizational culture is observed. Coaches can influence the sports training activities and manage the organizational culture in the clubs through the factors mentioned above when players are still young. The study is not representative of the South-West League and Bulgaria as a whole. Organizational culture significantly influences competing efficiency and good youth football players’ making.

STUDY OF THE IMPACT OF THE DEVELOPMENT OF SOCIAL INFRASTRUCTURE ON THE MIGRATION ATTRACTIVENESS OF THE TERRITORY USING THE METHODS OF ECONOMIC AND MATHEMATICAL MODELING

The article is devoted to the study of migration processes in Russia. The population migration forms the settlement system, has a significant impact on the social and economic development of the regions, it is a reflection of the high level of their differentiation on various features, leads to a change in balance both between macroregions and between the types of settlements. The problem of migration outflow in recent years has become characteristic not only for the Northern and Far Eastern regions of the country, but also for other subjects, including the Republic of Bashkortostan. In such conditions, the need to solve it is facing the authorities at all levels of management. At the same time, these issues are not directly reflected in national projects. Moreover, many indicators used in the strategic development documents of the federal level today, in fact, cannot be applicable to the purposes of predicting migration processes due to the lack of a sufficient retrospective base. Taking into account the impossibility of direct impact on the migratory behavior of the population, priority is given to creating favorable conditions. With such a formulation of the task, not financial and economic indicators of development, and the living conditions of people and, first of all, access to social infrastructure facilities are published. In this aspect, its development becomes a competitive control tool for human capital. However, as the study showed, the effectiveness of the implementation of similar activities is significantly varied in a particular region. For a quantitative assessment of the influence of the factors under consideration, the migration processes were asked to form the appropriate economic and mathematical model. The article briefly considers the prerequisites and features of its formation. According to the results of the study, the regression equation was obtained and dispersion analysis was carried out. The results of the assessment of the model according to the Russian regions confirm its adequacy. The study allows you to more fully assess the impact of the development of social infrastructure on the demographic situation in Russia.

A serum-stable RNA aptamer specific for SARS-CoV-2 neutralizes viral entry

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has created an urgent need for new technologies to treat COVID-19. Here we report a 2′-fluoro protected RNA aptamer that binds with high affinity to the receptor binding domain (RBD) of SARS-CoV-2 spike protein, thereby preventing its interaction with the host receptor ACE2. A trimerized version of the RNA aptamer matching the three RBDs in each spike complex enhances binding affinity down to the low picomolar range. Binding mode and specificity for the aptamer–spike interaction is supported by biolayer interferometry, single-molecule fluorescence microscopy, and flow-induced dispersion analysis in vitro. Cell culture experiments using virus-like particles and live SARS-CoV-2 show that the aptamer and, to a larger extent, the trimeric aptamer can efficiently block viral infection at low concentration. Finally, the aptamer maintains its high binding affinity to spike from other circulating SARS-CoV-2 strains, suggesting that it could find widespread use for the detection and treatment of SARS-CoV-2 and emerging variants.

Econometric model for evaluating correlation of performance indicators of a stevedoring company

В статье с целью оптимизации процесса управления ресурсами обоснована необходимость разработки эконометрической модели, учитывающей отраслевую специфику предприятия. На ее основе управленческий аппарат получает возможность оценить взаимосвязи факторов эффективности деятельности стивидорной компании, что усиливает обоснованность принимаемых решений. Цель исследования – построение эконометрической модели, позволяющей оценить тесноту взаимосвязи между показателями экономической эффективности хозяйственной деятельности стивидорной компании и измерить их взаимное влияние. Методы исследования. В процессе проведения исследования были использованы устный опрос, корреляционно-регрессионный и дисперсионный анализ, статистическое наблюдение. Результаты. В работе проведены исследования степени взаимного влияния показателей, характеризующих эффективность деятельности стивидорной компании. Информационная база сформирована посредством применения опроса, наблюдения, анализа статистических данных, что демонстрирует высокое качество собранного материала. Заключение. В статье представлена авторская эконометрическая модель, применяемая для оценки взаимосвязей показателей эффективности деятельности стивидорной компании. На основании результатов проведенных исследований предложены общие рекомендации, реализация которых сформирует условия для роста эффективности работы предприятия. Предложенная модель отражает специфику ведущих предприятий портовой отрасли и может быть применена для оценки взаимосвязей показателей эффективности портовых терминалов. The article in order to optimize the resource management process is substantiated the need to develop an econometric model that takes into account the sectoral specifics of the enterprise. On the basis of its basis, the management apparatus is able to assess the relationship of the factors of the effectiveness of the stevedoring company, which increases the validity of the decisions made. The purpose of the study is to build an econometric model that allows us to assess the relationship of the relationship between the indicators of the economic efficiency of the economic activity of the stevedoring company and measure their mutual influence. Research methods. In the process of conducting research, an oral survey was used, correlation-regression and dispersion analysis, statistical observation. Results. The paper conducted studies to the degree of mutual influence of indicators characterizing the effectiveness of the activities of the stevedoring company. The information base is formed by applying a survey, observation, analysis of statistical data, which demonstrates the high quality of the material collected. Conclusion. The article presents the author's econometric model used to assess the relationship of the performance of the stevedoring company. Based on the results of the research, general recommendations were proposed, the implementation of which will form the conditions for the increase in the efficiency of the enterprise. The proposed model reflects the specifics of the leading enterprises of the port industry and can be applied to assess the relationship of the effectiveness of pore terminals.