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This review of soil erosion (SE) studies in Russia focuses on two main tasks: (i) ensuring the completeness and reliability of SE data in Russia, a large country (17.1 million km2) with a variety of natural and socio-economic causes of land degradation, (ii) assessing the possibility of including a SE indicator among the indicators of land degradation neutrality (LDN). A wide range of statistical, remote sensing, mathematical modeling data, the results of scientific and field studies obtained at different levels were analyzed. It is asserted that in Russia the total area of eroded lands and those under erosion risk occupy more than 50% of all agricultural lands, whereas soil fertility of croplands decreased in Soviet time (from 1950s to 1980s) by 30–60% only due to water erosion. However, recent scientific studies indicate a decrease in erosion rate and in the area of eroded land during the last 30–40 years as a result of abandonment of arable land and subsequent overgrown with natural vegetation. The climate change resulting in decrease of the depth of soil freezing, flow of spring runoff also adds to the decrease of soil erosion. The SE indicator was suggested as an important complement to three global LDN indicators. At national and subnational level, it can be interpreted through such indices as “Rate of soil loss” (ton ha-1 yr-1) and “Total soil loss” (1000 tons, in certain area during selected time period). At local level the set of indices can be wider and site-specific, including those obtained through remote sensing data by using the classifier of thematic applications of remote sensing technologies; the example was tested at the local site.

Several glycoconjugates of the diterpenoid isosteviol (16-oxo-ent-beyeran-19-oic acid) with a 1,2,3-triazolyl moiety were synthesized, and their cytotoxicity was evaluated against some human cancer and normal cell lines. Most of the synthesized compounds demonstrated weak inhibitory activities against the M-HeLa and MCF-7 human cancer cell lines. Three lead compounds, 54, 56and 57, exhibited high selective cytotoxic activity against M-HeLa cells (IC50= 1.7–1.9 μM) that corresponded to the activity of the anticancer drug doxorubicin (IC50= 3.0 μM). Moreover, the lead compounds were not cytotoxic with respect to a Chang liver human normal cell line (IC50> 100 μM), whereas doxorubicin was cytotoxic to this cell line (IC50= 3.0 μM). It was found that cytotoxic activity of the lead compounds is due to induction of apoptosis proceeding along the mitochondrial pathway. The present findings suggest that 1,2,3-triazolyl-ring-containing glycoconjugates of isosteviol are a promising scaffold for the design of novel anticancer agents.

The optical properties of lead sulfide quantum dots (QDs) of different sizes embedded in a nanoporous silicate glass matrix (NSM) are investigated by steady-state and transient photoluminescence spectroscopy. The use of this matrix allows the fabrication of samples with reproducible optical characteristics, for both isolated and close-packed QDs. Low-temperature PL analysis of isolated QDs with sizes of 3.7 and 4.5 nm shows that the coefficient of temperature shift of the PL position changes sign with reducing QD size because of size-dependent contributions from thermal expansion, mechanical strain, and electron–phonon coupling. The PL intensity is determined by size-dependent splitting of the lowest energy electronic state.

The authors proposed a novel method of formation of polymer/metal hybrid interfacial layer with switchable properties by using ultrasonication. Intensive ultrasonication leads to the formation of a rough metal interface and triggers free-radical polymerization of monomers in the interfacial region of metal surface. Thus, polymer layer exhibits excellent adhesion to the bulk metal. The novel concept was demonstrated for polypyrrole/aluminum systems. Hydrophilic/hydrophobic properties and corrosion resistance also due to doping/dedoping of polypyrrole of the interfacial layers can be adjusted based on particular application. The proposed method can serve as a platform for formation of interfaces with self-regulating properties: self-healing, switchable hydrophylicity.

A CCD camera operating at T = 65 K was mounted in the vacuum space of our nuclear demagnetization cryostat. This has allowed us to make observations of3He crystals at temperatures below the superfluid phase transitions, in contrast to direct optical observations, which have so far been limited to T = 20 mK.1 The good thermal equilibrium provided by the superfluid allows us to nucleate single crystals of3He in the region of the cell visible to the optical system. This occurs either spontaneously (due either to gravitational pressure gradients or local surface defects) or as a result of a small applied heat pulse.

With the help of a new experimental technique strong anisotropy of the mobility of ions has been observed in hcp4He crystals. The mobility of positive ions in the direction of the six-fold axis is found to be 200 times higher than in the perpendicular direction. Activation energies of the mobility have been measured in both principal directions. They are equal to: 5.3K in the direction of theC6-axis and 11K in the perpendicular direction. The behaviour of the ions' velocity in the strong electric field regime is also studied as a function of the orientation.

The reactions of isosteviol methyl ester 1 with 1,3-dibromopropane, 1,2-dibromoethane and 1-bromopropane give rise to 15-bromoisosteviol methyl ester 2.

The first compound with a tweezer-like structure in diterpene derivatives of the kaurane series was obtained in the reaction of the acid chloride of isosteviol with diethylene glycol.

Isosteviol forms a crystalline molecular complex with aniline in the ratio 2:1, whose supramolecular structure looks like a double chiral helix cross-linked by aniline molecules.

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