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The era of chemotherapy began in the 1940s, which is the basis of traditional antitumor approaches and, being one of the most high-tech treatment methods, is still widely used to treat various types of cancer. A promising direction in modern medicinal chemistry is currently the creation of hybrid molecules containing several pharmacophore fragments of different structures. This strategy is successfully used to increase the therapeutic efficacy of cytotoxic agents and reduce side effects. In this work, we synthesized 10 1-aryl derivatives of benzimidazole and benzotriazole and 11 hybrids based on them. Among the compounds obtained, the most promising hybrid molecules were diphenylamines, containing an amino group and a benzotriazole cycle in the ortho position to the bridging NH group, which showed significant cytotoxic activity, excellent antioxidant properties and the ability to suppress the migration activity of tumor cells. Taken together, our results demonstrate that substituted diphenylamine-based bipharmacophoric compounds may serve as a promising platform for further optimization to obtain effective antitumor compounds. [ABSTRACT FROM AUTHOR]

Ebola virus (EBOV) is a type of RNA virus from the family of Filoviridae. The 2014-2016 Ebola outbreak in African countries Guinea, Liberia, and Sierra Leone has a total of 28,616 cases and 11,310 deaths. Death from Ebola is mainly caused by multi-organ failure due to internal bleeding and fluid loss. Another Ebola outbreak spiked this February 2021, suggesting the low effectiveness of the previous vaccines used. Zaire Ebola virus (EBOV) is known to be the species highly involved in the recent outbreak with a high mortality rate. This study is carried out to design a Bcell epitope Ebola vaccine based on the conserved region of Zaire EBOV glycoprotein. Reverse vaccinology and immunoinformatics approaches are used in this study. Samples of Zaire EBOV glycoprotein sequences were retrieved from GenBank, NCBI. The 3D modeling was done using the SWISSMODEL web server and PyMol software. Phylogenetic tree analysis was also done using MEGA X. B-cell epitope prediction was done by BepiPred 2.0 and Emini Surface Accessibility using the IEDB web server. Epitopes were selected based on their conservancy by comparing the sequences with the MEGA X alignment result. Antigenicity, allergenicity, and toxicity properties of the peptides were predicted using VaxiJen 2.0, AllerTOP 2.0, and ToxinPred web servers. In silico cloning was done as the final step using the pET-24a(+) expression vector. This study revealed that peptides “LEIKKPD,” “TGFGTNETEYLF,” “PYFGPAA,” “PYFGPA,” and “KLSSTNQL” are the best candidate for the B-cell epitope vaccine. Phylogenetic tree and 3D modeling successfully showed the genetic and structural differences of Zaire EBOV GP originating from various countries. In silico cloning was also done using the pET28a(+) expression vector to design a clone vector map for the next vaccine development phase. [ABSTRACT FROM AUTHOR]

Using the methodology of "click" chemistry, a singular method has been developed for the synthesis of unique conjugates based on sesquiterpene lactones: dehydrocostuslactone and alantolactone with polyalkoxybenzenes. To expand the structural range of the resulting conjugates, the length of the 1,2,3-triazole spacer was varied. For all synthesized compounds, the cytotoxic profile was determined on the cell lines of tumor origin (SH-SY5Y, HeLa, Hep-2, A549) and normal Hek 293 cells. It was found that the compounds based on alantolactone 7a–d with a long spacer and substances containing dehydrocostuslactone 10a–d with a short spacer have the greatest toxic effect. The decrease in cell survival under the action of these conjugates may be due to their ability to cause dissipation of the transmembrane potential of mitochondria and inhibit the process of glycolysis, leading to cell death. The obtained results confirm the assumption that the development of conjugates based on sesquiterpene lactones and polyalkoxybenzenes can be considered as a promising strategy for the search for potential antitumor agents. [ABSTRACT FROM AUTHOR]

Global warming and climate change are some of the most widely discussed topics in today's society, and they are of considerable importance to agriculture globally. Climate change directly affects agricultural production. On the other hand, the agricultural sector is inherently sensitive to climate conditions, and this has made the agricultural sector one of the most vulnerable sectors to the effects of global climate change. Rising CO2 levels in the atmosphere, increased temperature, and altering precipitation patterns all substantially influence agricultural insect pests and agricultural productivity. Climate change has a number of implications for insect pests. They can lead to a decreased biological control effectiveness, particularly natural enemies, increased incidence of insect-transmitted plant diseases, increased risk of migratory pest invasion, altered interspecific interaction, altered synchrony between plants and pests, increase in the number of generations, increased overwintering survival, and increase in geographic distribution. As a consequence, agricultural economic losses are a real possibility, as is a threat to human food and nutrition security. Global warming will necessitate sustainable management techniques to cope with the altering state of pests, as it is a primary driver of pest population dynamics. Future studies on the impacts of climate change on agricultural insect pests might be prioritized in several ways. Enhanced integrated pest control strategies, the use of modelling prediction tools, and climate and pest population monitoring are only a few examples. [ABSTRACT FROM AUTHOR]

In recent years, the increase in population and the decrease in agricultural lands and water shortages have caused many problems for agriculture and farmers. That is why scheduling is so important for farmers. Therefore, the implementation of an optimal schedule will lead to better use of agricultural land, reduce water consumption in agriculture, increase efficiency and quality of agricultural products. In this research, a scheduling problem for harvesting agricultural products has been investigated. In this problem, there are n number of agricultural lands that in each land m agricultural operations are performed by a number of machines that have different characteristics. This problem is modeled as a scheduling problem in a flexible workshop flow environment that aims to minimize the maximum completion time of agricultural land. The problem is solved by programming an integer linear number using Gams software. The results show that the proposed mathematical model is only capable of solving small and medium-sized problems, and due to the Hard-NP nature of the problem, large-scale software is not able to achieve the optimal solution. [ABSTRACT FROM AUTHOR]

Strawberry (Fragaria spp.) is a non-climacteric fruit, widely consumed in several countries, but is extremely sensitive and susceptible to mechanical damage during harvest, transport and storage, reducing the shelf life. In order to prolong the shelf life of this product, edible starch-based coatings were developed, with propolis extract (MSP) and without the addition of ethanolic propolis extract (MS) and uncoated samples, used as control (MC). All samples were stored under isothermal conditions (4 °C ± 0.5 °C), for 10 days. Physicochemical analyzes (pH, mass variation, vitamin C, color and phenolic compounds) were carried out to characterize and identify the coating efficiency in the conservation of strawberries. The formulations of the coatings with and without the addition of propolis had a significant (p = 0.05) effect on the variation of fruit weight. The propolis coating showed greater stability in the vitamin C content and pH levels, up to the 10th day of cold storage, in comparison to the samples with starch coating and the control. The treatments (MS, MSP and MC) did not significantly influence (p > 0.05) the color and the content of total polyphenols. [ABSTRACT FROM AUTHOR]

The relevance of the study deals with the importance of improvement of student readiness to overcome IT-related obstacles in post-Soviet social studies education. In this regard, this paper aims at identifying the concept of pedagogical interaction in the information and educational environment and revealing the effective use of pedagogical interaction to improve student readiness to overcome IT-related obstacles. The leading research method used to solve the problem is teaching project, which allows an integrated treatment of methodology in developing student readiness to overcome IT-related obstacles. The paper presents such methods as creating positive motivation, arranging interactive educational cognitive and practical student activities and boosting the personal educational environment; it is shown that a distinctive feature of pedagogical interaction is the acquaintance of students with various elements of the information and educational environment, leading to the development of student readiness to overcome IT-related obstacles; it is found out that the use of pedagogical interaction in the information and educational environment ensures the purposefulness and efficiency of educational process; it is justified that using interactive means of information and educational environment in the context of arrangement of pedagogical interaction can enrich educational process, develop specific student skill that will definitely help them in future professional activities. The research materials are of practical value to the further expansion of functional and methodical aspects of using interactive media in the information and educational environment. [ABSTRACT FROM AUTHOR]

The Barents Sea system is often depicted as a simple food web in terms of number of dominant feeding links. The most conspicuous feeding link is between the Northeast Arctic cod Gadus morhua, the world's largest cod stock which is presently at a historical high level, and capelin Mallotus villosus. The system also holds diverse seabird and marine mammal communities. Previous diet studies may suggest that these top predators (cod, bird and sea mammals) compete for food particularly with respect to pelagic fish such as capelin and juvenile herring (Clupea harengus), and krill. In this paper we explored the diet of some Barents Sea top predators (cod, Black-legged kittiwake Rissa tridactyla, Common guillemot Uria aalge, and Minke whale Balaenoptera acutorostrata). We developed a GAM modelling approach to analyse the temporal variation diet composition within and between predators, to explore intra- and inter-specific interactions. The GAM models demonstrated that the seabird diet is temperature dependent while the diet of Minke whale and cod is prey dependent; Minke whale and cod diets depend on the abundance of herring and capelin, respectively. There was significant diet overlap between cod and Minke whale, and between kittiwake and guillemot. In general, the diet overlap between predators increased with changes in herring and krill abundances. The diet overlap models developed in this study may help to identify inter-specific interactions and their dynamics that potentially affect the stocks targeted by fisheries. [ABSTRACT FROM AUTHOR]

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ZnO single crystals with thickness up to 12 mm, 2 inches in “diameter” and weight of about 150 g have been grown from KOH, NaOH, and K2CO3 based hydrothermal solutions on the seeds of (0001) orientation. The addition of LiOH up to 3.0–4.5 mol/L allowed to decrease the growth rate of ZnO crystals along the 〈0001〉 crystallographic direction. For positive and negative monohedra, it was achieved 0.12 and 0.01 mm/day, respectively, at temperature 340 °С and ΔТ = 10 °С. The best ZnO etching agent was found to be the solutions 25 mol% HCl + 3 mol% NH4F at room temperature, and etching time 5 min. The dislocation density of ZnO crystals varied from 240 cm−2 to 3,200 cm−2 in the case of growth rates 0.04 mm/day to 0.11 mm/day, respectively. It was also found that ZnO crystals grown are stable in air, oxygen, nitrogen, and argon atmosphere as well as in vacuum at the temperatures up to 1,000 °C under thermal treatment during 4 h. [ABSTRACT FROM AUTHOR]

This paper presents two approaches to the error estimation for an approximate solution of Abel equation under the condition that the exact solution belongs to a compact set. The algorithms to find an error of finite dimensional approximation and to construct an area to which the exact and all approximate solutions of the problem belong are provided. As examples, compact sets of bonded mono-tonic or convex functions are considered. We have concluded that in certain cases it is more preferable to utilize one approach over the other. [ABSTRACT FROM AUTHOR]

MVP, a Methanococcus jannaschii voltage-gated potassium channel, was cloned and shown to operate in eukaryotic and prokaryotic cells. Like pacemaker channels, MVP opens on hyper polarization using S4 voltage sensors like those in classical channels activated by depolarization. The MVP S4 span resembles classical sensors in sequence, charge, topology and movement, traveling inward on hyper polarization and outward on depolarization (via canaliculi in the protein that bring the extra cellular and internal solutions into proximity across a short barrier). Thus, MVP opens with sensors inward indicating a reversal of S4 position and pore state compared to classical channels. Homologous channels in mammals and plants are expected to function similarly. MVP, a Methanococcus jannaschii voltage-gated potassium channel, was cloned and shown to operate in eukaryotic and prokaryotic cells. Like pacemaker channels, MVP opens on hyper polarization using S4 voltage sensors like those in classical channels activated by depolarization. The MVP S4 span resembles classical sensors in sequence, charge, topology and movement, traveling inward on hyper polarization and outward on depolarization (via canaliculi in the protein that bring the extra cellular and internal solutions into proximity across a short barrier). Thus, MVP opens with sensors inward indicating a reversal of S4 position and pore state compared to classical channels. Homologous channels in mammals and plants are expected to function similarly. [ABSTRACT FROM AUTHOR]

The most promising type of micro-optical gyro is a resonator gyroscope. At the same time, the principle of operation of all prototypes of resonator micro-optical gyroscopes developed to date involves scanning a passive ring resonator in frequency. We devoted this work to a new approach to the construction and operation principle of a resonator micro-optical gyroscope. This approach does not require scanning a passive ring resonator in frequency and is realized through the use of a Mach–Zehnder modulator with a passive ring resonator connected to one of its arms. It was shown that, with this approach, the angular velocity can be determined, first, by the difference between the maxima and minima of the radiation power at the output of the Mach–Zehnder modulator when the optical length of one of its arms is modulated and, second, by the displacement of these maxima and minima. A common drawback of all considered angular velocity measurement methods utilizing the Mach–Zehnder modulator is the limited measurement range. For the resonator considered in this paper, the measurement range is of the order of ±1500 rad / s. [ABSTRACT FROM AUTHOR]