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We review the present status of the Standard Model calculation of the anomalous magnetic moment of the muon. This is performed in a perturbative expansion in the fine-structure constant α and is broken down into pure QED, electroweak, and hadronic contributions. The pure QED contribution is by far the largest and has been evaluated up to and including O(α5) with negligible numerical uncertainty. The electroweak contribution is suppressed by (mμ∕MW)2 and only shows up at the level of the seventh significant digit. It has been evaluated up to two loops and is known to better than one percent. Hadronic contributions are the most difficult to calculate and are responsible for almost all of the theoretical uncertainty. The leading hadronic contribution appears at O(α2) and is due to hadronic vacuum polarization, whereas at O(α3) the hadronic light-by-light scattering contribution appears. Given the low characteristic scale of this observable, these contributions have to be calculated with nonperturbative methods, in particular, dispersion relations and the lattice approach to QCD. The largest part of this review is dedicated to a detailed account of recent efforts to improve the calculation of these two contributions with either a data-driven, dispersive approach, or a first-principle, lattice-QCD approach. The final result reads aμSM=116591810(43)×10−11 and is smaller than the Brookhaven measurement by 3.7σ. The experimental uncertainty will soon be reduced by up to a factor four by the new experiment currently running at Fermilab, and also by the future J-PARC experiment. This and the prospects to further reduce the theoretical uncertainty in the near future – which are also discussed here – make this quantity one of the most promising places to look for evidence of new physics.

The development of e-commerce requires the strengthening of this component of the pharmaceutical business while providing the population with medicines. Improving the operation of pharmacy websites is an important task with a significant marketing effect. The purpose of the study is to identify errors on pharmacy websites that worsen their usability and communicative qualities when interacting with visitors, to offer an approach based on a joint assessment of consumer perception and technical parameters, and to carry out calculations for a comparative analysis of such sites functional and technical components using a multi-criteria approach. The objectives of the study were to analyze the Internet trade in medicines, to determine the criteria for comparison of pharmacy sites, to develop a model for website evaluation, and to analyze the results of site quality estimation. Multicriteria comparison with different importance of criteria was used as the methodology to evaluate the usability of sites for online buyers of pharmaceutical products. As result two main components of the quality of pharmacy sites are identified: user interface and technical characteristics. The parameters of site evaluation for these components are described, and evaluation is performed. A computer model in Excel has been developed. The proposed approach and the program allow for assessing pharmacy sites’ quality, comparing their marketing opportunities, directions to improve functionality, pharmaceutical services, and business position of pharmacies. The described steps for website estimations can be used not only in pharmaceutical services but for wide kinds of sites for e-commerce.

Known technologies and methods for obtaining virus-free potato mini-tubers of a required size fraction do not fully provide the highest multiplication factor, which occurs due to the insufficient productivity of an individual potato plant. On the basis of long-term experimental data (2012…2022), an assessment of the effectiveness of methods for growing potato mini-tubers in open and protected ground conditions is given. According to the number of tubers harvested from one plant, all growing methods can be divided into two large groups: traditional (3-12 potatoes per plant) and modified (more than 40 potatoes per plant). A highly efficient method has been developed for obtaining mini-tubers of potatoes harvested as they grow on soil substrates with an average annual productivity of at least 50 mini-tubers from one micro-tuber and 40 mini-tubers from one virus-free plant (with traditional substrate methods – from 3 to 10 mini-tubers). Based on this method, there has been created a substrate technological module of a new generation harvesting tubers as they grow which makes it possible to obtain an average of 40 to 55 mini-tubers from one virus-free plant over the years, that is almost 10 times more in comparison with traditional methods of growing with a single harvest at the end of vegetation. Harvesting mini-tubers as they grow up to a required size creates the possibility of obtaining tubers of one size fraction (10-25 g), which allows later, when laying the nursery of the first field reproduction, to apply mechanized planting in the field and obtain uniform seedlings.

The present study has been carried out to determine the effects of four different illuminators with red, far-red, blue, and white light-emitting diodes (LEDs) on the growth, morphology, pigment composition, and chlorophyll fluorescence of spinach (Spinacia oleracea L.) of the ‘Zhirnolistny’ cultivar. We investigated these variants in two photon flux densities, 400–800 nm (PFD) 120 µmol m−2 s−1 and 180 µmol m−2 s−1. The studies were carried out in a climate chamber. Plant measurements were carried out on the 30th and 45th days of cultivation. The results showed that during the period of active growth, on the 30th day, spinach plants accumulated 2.6 and 2.4 times more fresh weight in the variant with a higher PFD (180 µmol m−2 s−1). At the end of the growing season, only a decrease in PFD had an effect on the fresh and dry weight of plants. The highest concentration of chlorophyll on both the 30th and 45th days of vegetation was found when spinach plants were grown under red-blue (RB) LEDs in a spectrum proportion of R70:B30. It was found that the variants had a higher proportion of green radiation in the spectrum of illuminators with PFD 180 µmol m−2 s−1, and the nitrate content in spinach was slightly lower than in other variants.

BACKGROUND: The COVID-19 pandemic has affected the emotional state of a wide range of people around the world. Studying the social and psychological factors of psychological distress is required in the context of the pandemic in different countries. This study aims to explore the relationship between the emotional state of Russian citizens during the COVID-19 pandemic and their perceptions of it, and its dependence on various socio-demographic characteristics. METHODS: A socio-demographic questionnaire, the Russian version of the Perceived Stress Scale, the State Scale from Spilberger State-Trait Anxiety Inventory, and the modified version of the Brief Illness Perception Questionnaire were used for the purposes of this study. The data was analyzed via descriptive statistics, ANOVA, Exploratory Factor Analysis, Correlation Analysis, Scale Consistency Analysis, and Structural Equation Modeling (Path Analysis Method). RESULTS: The study sample consisted of 1192 Russian-speaking respondents. The findings suggest that psychological distress affects all components of the ideas about the pandemic. The "Psychological distress" variable positively influences the "Threat to life" and "Fear of an unknown disease" components of the ideas about the pandemic, whereas the "Control" component (ideas about the ability to control events) is ambivalent. On the one hand, the severity of psychological distress reduces the idea of being able to control events; on the other, the psychological distress experienced increases the feeling of threat and uncertainty, and stimulates the control of these feelings to be realized. In addition, significant differences were revealed in the nature of perceptions of the pandemic and psychological distress, as dependent on gender, age, type of employment, daily routine during self-isolation, income, as well as a fear of possible stigmatization with regard to COVID-19. It has been shown that underestimating the disease leads to improvement of psychological well-being. However, respondents who underestimated the danger of coronavirus paid less attention to the measures taken against the virus. If the respondent had relatives infected with COVID-19, they were found to perceive the COVID-19 pandemic as more threatening and less understandable. CONCLUSIONS: Through assessing a level of threat and fear of an unknown disease, we defined that psychological distress has a direct and mediated influence on the feeling of control over the pandemic. However, the results on the role of psychological distress and perceptions of the COVID-19 pandemic, taken together, appear rather contradictory. Further research exploring additional predictors of psychological well-being and distress during the COVID-19 pandemic is required to provide solid conclusions.

OBJECT. To consider problematic issues related to measurements of radionuclides in the air of the working area released during repackaging of bulk solid radioactive waste during decommissioning of nuclear energy facilities. To develop a method of direct measurements for operational control of the concentration of radioactive aerosols in the air of the working area, ensuring that the control level is not exceeded by the annual effective dose of personnel.METHODS. To solve this problem, the method of calculating the maximum possible number of alpha particles on the selected sample of the analytical filter AFA-RSP20 was used.RESULTS. A method of operational control of the radiation situation in the workplaces of personnel using direct measurements by portable radiation monitoring devices of the alpha particle flux density from the exposed AFA-RSP20 filter is proposed. The use of this method makes it possible to provide control in cases where the use of standard installations for measuring the volumetric activity of radioactive aerosols is unavailable or impossible. The article describes the relevance of the topic, the calculation of the reference level of the alpha particle flux density from the surface of the AFA-RSP20 filter is given.CONCLUSIONS. Passport characteristics of personal respiratory protection equipment do not provide convincing data on the operation of the filter with a specific pollutant. For the correct decision-making on the use of certain types of personal respiratory protection by personnel working with radioactive waste containing transuranium radionuclides, it is necessary to control the volumetric activity of radionuclides in the air. Based on calculations and direct measurements, it is shown that the use of an operational method for measuring the alpha particle flux density from an exposed AFA-RSP20 filter makes it possible to monitor the radiation situation at personnel workplaces during decommissioning of nuclear energy facilities.

Food insecurity is a top economic and national security concern in many countries, and scientists worldwide are working to increase crop productivity in order to address this issue. In line with this information, the present study aimed to test the possibility of improving the yield and fruit quality of two tomato cultivars, namely 'Vspyshka' and 'Lyana'. The effect of LSL (light of sodium lamps—control) and the short additional 4 h treatment of nighttime LED lighting (LSL+night LED) with an increase in the proportion of red, blue, and far-red spectra on tomato fruit yield as well as its physiological, biochemical, and consumer attributes were compared in this study. The results suggested that LSL+night LED significantly increased soluble solids concentration, vitamin C content, and polyphenolic compounds of tomato fruits, taking into account the varietal characteristics. Moreover, a moderate to high relationship was also observed between the polyphenolic complex, vitamin C content, and antioxidant activity. It was concluded that the LSL+night LED could further enhance the relationship between polyphenols and antioxidants, as well as soluble solids concentration. LSL+night LED treatment also provided an increased accumulation of five essential amino acids associated with the taste characteristics of fruits, namely histidine, valine, threonine, licin, and the sum of isoleucine. In addition, the contents of lysine and methionine increased in the 'Lyana' cultivar. LSL+night LED treatment was also noted to have a less pronounced effect on the contents of aspartic acid and asparagine, as bio stimulators of plant growth processes, as well as the amino acids arginine, serine, glycine, and tyrosine, which were additionally consumed to restore photosynthesis. LSL+night LED treatment reduced the concentration of nitrates in fruits, which is a toxic element for human health. Overall, the results of the study are believed to be demanded in practical applications, with potential benefits in improving the elements of resource-saving technology for growing vegetable crops. [ABSTRACT FROM AUTHOR]

Modern developments in data analysis techniques and evolutionary optimization algorithms have made it possible to analyze large amounts of unstructured digital data sets. Based on the differential evolution algorithm and semiclassical quantum simulations, we have recently proposed a method for classifying and analyzing the optical properties of organic pigments. In this paper, we present the results of modeling the absorption spectra of five carotenoids synthesized during the vital activity of the ascomycetous fungi: neurosporaxanthin, neurosporene, torulene, γ-carotene, and ζ-carotene. We calculated the absorption spectra for each pigment using the multimode Brownian oscillator theory, which allows us to evaluate the influence of molecular vibrations on the electronic transitions in the pigment. We applied a generalized spectral density function method to our modeling, taking into account the contributions of 13 vibrational modes with frequencies varying between 100 cm−1 and 3000 cm−1. This approach allowed us to gain a deeper understanding of how molecular vibrations affect the absorption spectra of these organic compounds. Thus, each absorption spectrum was associated with a unique set of Huang–Rhys factors (which represent the effective electron–phonon interaction). This set can be considered as a kind of "fingerprint" that characterizes the optical response of the pigment in the solvent. [ABSTRACT FROM AUTHOR]

In the context of armed conflicts, regions often face infrastructure destruction and economic difficulties. The development of tourism can be a key factor in recovery and economic growth. Geospatial platforms for interactive charitable tourism offer a promising solution for attracting tourists and stimulating the development of affected regions. The aim of this study is to assess the effectiveness of geospatial platforms for interactive charitable tourism as a tool for attracting tourists and promoting the recovery and development of regions affected by armed conflicts. This study employed regression and correlation analysis methods. The analysis revealed significant positive correlations for all variables. The correlation coefficient for audience reach was 0.75, for the effectiveness of attracting donations—0.8, for the economic impact on the region—0.9, for user interaction with the platform—0.85, for platform sustainability—0.78, and for social impact—0.92. The t-statistic values exceeded the critical thresholds, and the p-values were below 0.05, confirming the statistical significance of the results. The coefficient of determination was 0.91, indicating a high explanatory power of the model. For the four obtained clusters, approaches to the development and use of geospatial platforms were justified. For regions of Cluster 1 with high audience reach (0.75) and moderate effectiveness of attracting donations (0.8), it is recommended to use technologies to improve connectivity and effectively promote their strengths. For regions of Cluster 2 with high sustainability and high tourism potential (high social impact = 0.92), it is necessary to include advanced geospatial solutions to increase visitor engagement and optimize recovery strategies, building on existing strengths to attract more tourists and stimulate sustainable development. For regions of Cluster 3, significant investments are required both in geospatial platforms and in tourism infrastructure to benefit from high tourism potential (economic impact on the region = 0.9). Strategic development and targeted marketing should be a priority to attract tourists and stimulate economic growth. Regions of Cluster 4 with low sustainability and tourism potential (low user interaction with the platform = 0.85 and platform sustainability = 0.78) require comprehensive support, as they are in a crisis situation. [ABSTRACT FROM AUTHOR]

Lighting conditions are an important controller of plant growth and development, and they affect secondary metabolite synthesis. In this research, we explored the effect of additional UV irradiation of various ranges in addition to the main one at PPFD 160 µmol m−2 s−1 on the accumulation of some secondary metabolites of stevia (Stevia rebaudiana Bertoni). The fresh weight of leaves was slightly higher under additional UV-A and UV-B irradiation compared with the control variant, and the leaf surface area was significantly larger, respectively, by 23.3 and 20.7% than in the control variant, while the rate of photosynthesis did not decrease. Plants under additional UV-B and UV-C irradiation were under the greatest light stress, as evidenced by a decrease in antioxidant capacity by an average of 30% compared to the control and UV-A. The total flavonoid content was significantly higher (by 74%) under UV-B irradiation. The highest concentration of steviol glycoside was observed during budding and flowering under UV-B and UV-C irradiation (by 13.2 and 11.3%, respectively). Analysis of hyperspectral images, chlorophyll fluorescence, and vegetation indices showed light stress increasing under UV-C irradiation, which caused an increase in the relative chlorophyll content, scorches, leaf morphology changes, a CO2 absorption rate decrease, and plant growth inhibition. UV-B irradiation can be used as an optimal type of irradiation based on a set of indicators.

The methodical approaches to optimization of soil indicators of chernozems with natural fertility for obtaining high-quality grains of soft winter wheat were considered in the work. The purpose of the study is to substantiate the determination of the optimal levels and ratios of main grain quality indicators (protein, gluten, vitrification) and soil indicators of chernozem, which ensure high quality of winter wheat grain. Research methods are direct field studies, laboratory-analytical and mathematicalstatistical calculations, and optimization. It was obtained on podzolized chernozems with optimization of soil indicators - protein content - 14.7%, gluten -20.2%, vitreousness - 62%; on typical chernozems - protein content - 14.6%, gluten - 23.7%, vitreousness - 51%; on ordinary chernozems - protein content - 16.1%, gluten - 35.7%, vitreousness - 60%; on the southern chernozems - protein content - 16.6; gluten - 34.2%, vitreous - 79%. The development approach and results allow for determining the regions of cultivation of high-quality soft winter wheat grain on the territory of Ukraine that is important for farmers, as well as for the agricultural economy in general.

The possibility of pigment detection and recognition in different environments such as solvents or proteins is a challenging, and at the same time demanding, task. It may be needed in very different situations: from the nondestructive in situ identification of pigments in paintings to the early detection of fungal infection in major agro-industrial crops and products. So, we propose a prototype method, the key feature of which is a procedure analyzing the lineshape of a spectrum. The shape of the absorption spectrum corresponding to this transition strongly depends on the immediate environment of a pigment and can serve as a marker to detect the presence of a particular pigment molecule in a sample. Considering carotenoids as an object of study, we demonstrate that the combined operation of the differential evolution algorithm and semiclassical quantum modeling of the optical response based on a generalized spectral density (the number of vibronic modes is arbitrary) allows us to distinguish quantum models of the pigment for different solvents. Moreover, it is determined that to predict the optical properties of monomeric pigments in protein, it is necessary to create a database containing, for each pigment, in addition to the absorption spectra measured in a predefined set of solvents, the parameters of the quantum model found using differential evolution.

Human capital in any organization is one of the key assets. But not many managers are able to assess human capital in financial terms, as well as determine the financial value of this asset. Most of the organization’s human capital is made up of labor. The amount of this capital is also influenced by the management of human capital itself and culture.

One of the most important problems during the implementation of any technology is to reduce labor costs, energy, and resource conservation while increasing the yield of cultivated crops and, as a result, reducing the cost of production. Despite a significant amount of scientific research devoted to the problem of energy and resource conservation in the cultivation and harvesting of agricultural crops and the development of mechanization tools that ensure the high-quality performance of technological operations, there remain issues that have not been fully resolved to date. In addition, not all the results of known theoretical and experimental studies can be directly applied to intensify the process of harvesting root crops since the quality indicators of marketable products depend on the type and technological parameters of the separating working bodies. This article presents the design of a rod elevator with an adjustable angle of inclination of the web, which reduces damage to commercial products of root crops and bulbs with maximum completeness of separation. A laboratory facility has been developed to substantiate the design and technological parameters of a separating system with an adjustable web inclination angle. Based on the results of theoretical and experimental studies, a machine for harvesting onions with an adjustable blade inclination angle has been developed, which provides an increase in the quality indicators of onion harvesting at optimal values of the parameters: (1) translational speed of movement of the rod elevator with an adjustable web inclination angle of 1.7 m/s with a 98.4% completeness of separation and 1.7% damage to the bulbs; (2) translational speed of the movement of the machine for harvesting root crops and onions 1.0 m/s with a 98.5% separation completeness and 1.1% damage to the bulbs; (3) digging depth of the digging plowshare equal to 0.02 m, with an onion heap separation completeness of more than 98% and product damage of less than 1.4%. The results of theoretical and experimental studies of a rod elevator to substantiate the design and technological parameters during its interaction with a heap of onion are presented. Basic design and technological parameters of the studied rod elevator are substantiated, namely, the distance S1 of the movement of the rod of the actuators, the angle a1 of the longitudinal inclination of the surface of the rod elevator relative to the horizon, and differential equations of motion of the onion-sowing pile element on the surface of the rod elevator with an adjustable angle of inclination of the web.

Introduction. The accelerated deployment of modern electronics contributes to the efficiency of agricultural activities. The aim of the study is to develop automated machines with digital control systems for cultivating, harvesting and post-harvest processing of vegetable crops and potatoes. Materials and Methods. The article describes the technique of analytical studying the development of automated machines for cultivating, planting, harvesting and post-harvesting with automation in separate technological operations according to the technique of comprehensive assessment of performance quality and stability of technological operations on the basis of quantitative optimization criteria. Results. It is found that for the development of control and monitoring system of the technological process, it is necessary to provide automatic adjustment of the main technological parameters of the machines. These parameters should include the uniformity of soil density when seeding down, recording the force impact of the working body on the soil layer below or above the specified limits of the soil density toleration, changing and maintaining the vibration frequency of separation intensifiers, identifying commercial products through the vision system in the form of a camera, respectively. Discussion and Conclusion. The results of the study on the development of algorithms and hardware-software means of the functioning of automated machine individual elements have resulted in ensuring the implementation of automation segments on the main operations of crop production: tillage, seeding/planting, harvesting and post-harvest processing.

It was noted that increased soil moisture worsens the quality of harvesting root crops due to a decrease in the completeness of separation. To increase the separating capacity of a slotted cleaner for root crops, it was proposed to improve the heating of the separating surface with hot exhaust gas. (Research purpose) To optimize the design and technological parameters of an exhaust gas heat separation system of the sugar beet harvester power plant. (Materials and methods) Federal Scientific Agroengineering Center VIM developed an exhaust gas heat separation system for harvesting root crops and potatoes in high moisture conditions using the heat of the harvester power plant exhaust gases. The cleaning quality of the separating system of a self-propelled sugar beet harvester was determined under the gradual engine load from 0 to 100 percent of the nominal rated power. The temperature of the exhaust gases was measured with the assumption of changes in the engine load and its effective power. (Results and discussion) The experiment revealed an increase in the completeness of the separation of a root crops heap from 96.0 to 98.8 percent at 26-32 percent soil moisture due to the separation system in the form of a cleaning star, which uses the heat of the engine exhaust gases. The established optimal values of the factors under consideration are as follows: the separating star rotation rate is 21.8 revolutions per minute, the distance between the separating star and the deflector is 128.4 millimeters. (Conclusions) It was determined that the high quality of the technological process of root crops harvesting in high soil moisture conditions ensuring a 97-percent separation efficiency is possible if optimize the separating device design and technological parameters and maintain the separating star rotation rate at 20-22 revolutions per minute and the distance between the separating star and the deflector within 120-140 millimeters. The authors noted the prospects of developing this system and the need for theoretical and experimental studies to improve the design and technological process of the harvester separating system.