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In recent years, researchers have often encountered the significance of the aberrant metabolism of tumor cells in the pathogenesis of malignant neoplasms. This phenomenon, known as the Warburg effect, provides a number of advantages in the survival of neoplastic cells, and its application is considered a potential strategy in the search for antitumor agents. With the aim of developing a promising platform for designing antitumor therapeutics, we synthesized a library of conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones. To gain insight into the determinants of the biological activity of the prepared compounds, we showed that the conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones, which are cytotoxic agents, demonstrate selective activity toward a number of tumor cell lines with glycolysis-inhibiting ability. Moreover, the results of molecular and in silico screening allowed us to identify these compounds as potential inhibitors of the pyruvate kinase M2 oncoprotein, which is the rate-determining enzyme of glycolysis. Thus, the results of our work indicate that the synthesized conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones can be considered a promising platform for designing selective cytotoxic agents against the glycolysis process, which opens new possibilities for researchers involved in the search for antitumor therapeutics among compounds containing piperidone platforms.

In the recent decades, there has been increasing interest in the application of biochars (BCs) to soils to solve a wide range of problems: from sequestration of atmospheric carbon and long-term increase in fertility to their use as effective sorbents in the remediation of contaminated soils. However, uncontrolled use of low-quality BC has environmental risks associated with the danger of soil contamination with toxic by-products of pyrolysis. The aim of the work was to study the content and composition of labile hydrophobic by-products of pyrolysis (lipid fraction) extracted by organic solvents from BC obtained from various plant materials at different pyrolysis temperatures. Six types of BC prepared from corn and millet straw and willow wood by pyrolysis to final temperatures of 400 and 600°C (low- and high-temperature biochars, LT/BCs and HT/BCs, respectively) were used in the experiment. All HT/BСs had a significantly lower content of lipid fraction (CLF) compared to LT/BCs: 0.16–0.46 and 0.54–3.38% of the BC weight, respectively. Also, HT/BCs obtained were characterized by a higher content of total organic carbon (CTOC) with a lower proportion of organic carbon of the lipid fraction (CTOCLF). For a qualitative characterization of the lipid fraction, SUVA254 and Sr indices reflecting the degree of aromaticity and molecular weights of colored soluble organic compounds were calculated on the basis on the UV-VIS absorption spectra of their extracts. Based on the obtained results, it was concluded that, regardless of the feedstock, an increase of the final pyrolysis temperature resulted in the decrease in the degree of aromaticity and molecular weight of organic compounds in the lipid fraction. As pyrolysis temperature increased, the total content and proportion of polynuclear representatives of polycyclic aromatic hydrocarbons (PAHs)—the most dangerous by-products with high toxicity, carcinogenicity, and resistance to biodegradation—decreased. It was also found that the total PAH content in all LT/BCs exceeded the maximum permissible level (20 mg/kg) recommended by the International Biochar Initiative (IBI), while the total PAH content in the HT/BCs was below this value. Thus, a conclusion was made about the need to develop general quality standards for BCs produced for application to soil, taking into account the content of hydrophobic pyrolysis by-products, including PAHs, which are hazardous soil pollutants.

Light gray forest soils (Eutric Retisols (Loamic, Cutanic, Ochric)) were studied under a 20–25-yr-old fallow at the stage of overgrowing by meadow vegetation, pine, and birch. The studied area plot was confined to one element of topography, without morphological evidences of erosion processes, and with relatively homogenous soil texture. To assess the influence of fallow vegetation on the formation of soil organic matter (SOM), the plant cover was zoned according to vegetation indices calculated on the basis of remote sensing data. The k -means algorithms and the Random Forest method were used for this purpose. It was shown that there were statistically significant differences between the types of land cover in terms of the SOM stocks in the upper layer of the old-arable horizon with the specification of three and four clusters. The specification of three classes of vegetation on the fallow—coniferous woody vegetation, deciduous woody vegetation, and herbaceous vegetation—proved to be the most expedient; the correctness of their allocation was confirmed by the geobotanical survey of the territory. The results of a pairwise comparison of sites occupied by different types of fallow vegetation indicated that they significantly differ in the SOM stocks only in the uppermost 5-cm-thick layer of the old-arable horizon and only for the pair of coniferous woody and herbaceous vegetation. Differences in the accumulated humus stocks in the layer of 0–10 cm were statistically significant for the soils under deciduous and coniferous woody vegetation and under herbaceous and coniferous woody vegetation. There was no significant difference in this indicator between the soils under deciduous woody vegetation and herbaceous vegetation.

In a laboratory experiment, the effect of biochar (BC) on substrate-induced respiration (SIR) of soils was studied. In the experiment, 10 samples of BC obtained from woody and herbaceous materials in two modes of pyrolysis were used. The SIR was determined after 3 days and after 3 and 6 months of incubation. During short-term incubation, no effect of BC on SIR was observed. The exception was the corn-based BС application, when there was a 34.6% increase in SIR. After incubation for 3 months, a significant increase in SIR was found (from 30.4 to 54.8%) for five BCs were added. After incubation for 6 months, a significant increase in SIR (from 30.4 to 65.9%) was observed when eight BCs were applied. LASSO regression and 23 parameters of BC properties were used as potential predictors to evaluate BC properties that affect SIR. It was found that during three-day incubation, the following properties of BС have a positive effect on SIR: the contents of oxidizable organic matter (OM) and exchangeable calcium and the pH of water suspension; the content of exchangeable sodium had a weak negative effect. At incubation for 3 months there is a positive effect of oxidized OM; and after 6 months, the ash content. Since only a positive statistically significant effect of BC on SIR was observed in the experiments, it was concluded that in order to objectively assess the efficiency of BC use for CO 2 sequestration in soils, balance calculations are necessary. In these calculations, along with the amount of stable carbon introduced into soils with BC, a potential increase in CO 2 emissions from soils due to the activation of soil saprophytic microbiota should be taken into account.

On the basis of material from expeditions to the Laptev Sea in 2014, information is presented on occurrence, spatial-bathymetric distribution, water temperature and salinity, and types of ground in habitats of six species of eelpouts: shulupaoluk Lycodes jugoricus , pale eelpout L. pallidus , polar eelpout L. polaris , Arctic eelpout L. reticulatus , archer eelpout L. sagittarius, and wattled eelpout L. cf. palearis. Specimens similar to the wattled eelpout L. cf. palearis are found in this sea for the first time—in shallow water of Kotelniy Island (20–43 m). The polar eelpout is a common, relatively abundant, and widely distributed species in the Laptev Sea. Its frequency of occurrence is 24.7 vs. 1.2−6.2% of the other five species. The size of captured specimens, as well as the length-weight ratio of shulupaoluk and polar eelpout, is reported. Diet composition of shulupaoluk, polar eelpout, and Arctic eelpout is examined.

A procedure for extraction of variations in the ionospheric total electron content (TEC) caused by the presence of local regions containing small-scale irregularities of the electron concentration has been developed. The procedure employs the transionospheric sounding data obtained with the use of a double-frequency GPS/GLONASS receiver. The procedure is based on extraction of individual components of the TEC time series by applying to the series the procedure of simple sliding-window smoothing with the width of the window selected according to the period of the TEC variations caused by the various-scale ionospheric irregularities. The efficiency of the procedure is demonstrated by the actual measurement data.

A possibility of the ionosonde coverage expansion due to applying navigation satellite systems for supplying with the reliable short-wave radio communication acting along extended radio paths including multihop radio paths. It is shown on the basis of processing experimental data that the functionality increase of the vertical sounding ionosonde can be provided using the hardware-software ionospheric sounding complex that uses data of navigation satellites. The application of this complex in the place, where the vertical sounding ionosonde is located, allows to obtain the detailed picture of the electron concentration distribution not only far from the ionosonde but also inside the sounding region itself, along the trajectories that all points located under the ionosphere follow and that cross the responsibility zone of the vertical sounding station. It is shown that it is possible to create the dense network of the ionospheric control on the basis of vertical sounding stations distributed over a territory and hardware-software complexes.

The first record of the Greenland shark Somniosus microcephalus (Somniosidae) at the northern boundary of the Laptev Sea (78°04.3 N, 133°24.4 E) is described; this site is 1500 km eastward of any earlier records for this species in the Barents Sea and adjacent regions of the Kara Sea. A young male with an total length of 260 cm was caught in September 2014 by a bottom trawl at a depth of 240 m. Maps of the capture sites for S. microcephalus individuals in the Barents Sea and adjacent waterbody are presented. It is assumed that this shark came to the continental slope of the Arctic Ocean with a relatively warm flow of Atlantic origin, running along the northern Arctic shelf edge.

The research is aimed at creating a mathematical model that allows describing the movement of cargo fixed on the deck of a ship, depending on a number of physical parameters acting on the cargo. The study is relevant in connection with the need to minimize the harmonic movement of a fixed cargo on the deck and prevent its resonating with the vibration of the vessel. During the development of the model, a number of assumptions were made: the case was considered when the load moves along the deck in one plane, and the fastening system presses it to the surface of the deck with a given coefficient of resistance. Under the given constraints, a mathematical model was created that allows determining the trajectory of the cargo fixed on the deck. The cases are considered: the friction force of the load on the surface is zero, the friction force on the surface is proportional to the square of the speed of movement in accordance with the analytical equations of motion of the object fixed on the deck of the vessel. The analysis of the resulting model will allow us to develop measures to optimize the fastening of cargo on the deck.

— Information on the distribution and occurrence of three species of the genus Liparis , Liparis bathyarcticus Parr, 1931, L. cf. fabricii Krøyer, 1847 and L. tunicatus Reinhardt, 1836 on the shelf of the Laptev and East Siberian seas, depending on the temperature, salinity and sediment types is presented according to the data of trawl surveys in 2014 and 2017. L. cf. fabricii is the most common species in the surveyed water area with the frequency of occurrence of 22.4% in the Laptev Sea and 24.7% in the East Siberian Sea. The total relative abundance and biomass of all species of the genus Liparis in the East Siberian Sea (377.7 ind./km 2 and 9.14 kg/km 2 ) were slightly higher than in the Laptev Sea (326 ind./km 2 and 8.32 kg/km 2 ). The maximum length of L. tunicatus in the East Siberian Sea (172 mm) exceeds the previously known one (160 mm). The average length and weight of fish of all three species of Liparis in the East Siberian Sea are greater than in the Laptev Sea.