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The interest in studying the distribution of actinomycetes in natural ecosystems is the result of a large-scale use of these organisms in biotechnological industry (actinomycetes produce 45% of all biologically active substances of microbial origin). In this study, the objects for isolating actinomycetes are the eutrophic peat soils of bog ecosystems of different geneses under deciduous, mixed, and coniferous forests (Zapadanaya Dvina district of Tver oblast, European territory of Russia and Tomsk district of Tomsk oblast, Western Siberia). In total, 120 cultures of actinomycetes were isolated from the zone of active organic detritus decomposition represented in the studied soils by litter and eutrophic peat horizon; most of them are identified as Streptomyces (38 species). According to the analysis of antimicrobial activity, 40% of the isolated cultures concurrently display an antagonistic effect against bacteria, fungi, and opportunistic microorganisms, including the strains with a wide range of antagonistic action— Streptomyces g lobisporus , S . sindenensis , and S . xanthochromogenes . The observed antifungal activity of streptomycetes is higher as compared with the antibacterial effect. S . aburaviensis and S . albaduncus display the highest multiple antibiotic resistance. In total, 82% of the isolates display a cellulolytic activity and 26%, a chitinolytic activity. The cultures of S . bikiniensis , S .  varsoviensis, and S . alboflavus have a high hydrolytic activity.

Structural indicators (abundance and diversity) of the fungal and actinomycete complexes of eutrophic peat soils in the zone of active organic detritus decomposition, namely, litter (L and F layers) and eutrophic peat horizon (TE), were analyzed. Samples were e taken in swamped forests (black alder, pine, birch, and mixed forest stands) of the Tver and Tomsk oblasts (Russia) in summer of 2021. The abundance of mycelial organisms was measured by fluorescence microscopy and plate method. Species of culturable representatives were identified by their phenotypic traits. The fungal mycelium in the litter is two–tenfold longer as compared with the TE horizons; the abundance of culturable fungi is bigger by two‒three orders of magnitude; and that of actinomycetes, by one‒two orders of magnitude. The litter fermentative layer (F) displays the maximum carbon content of the mycelial component (3‒10 mg C/g). The stocks of actinomycete biomass in the zone of active organic detritus decomposition varies from 23 to 60 kg/ha and of fungal biomass, from 1593 to 3718 kg/ha. The share of litter in the total stock of mycelial biomass across the profile is larger in deciduous forests. In total, 70 species of culturable fungi belonging to 43 genera and 42 actinomycetes species of 12 series and 4 sections were isolated from the zone of active organic detritus decomposition. Representatives of Penicillium, Talaromyces, and Trichoderma genera are prevalent in the fungal complex and of Streptomyces, in the actinomycete complex. The litter does not yield to the TE horizon in terms of species diversity of both fungi and actinomycetes. The species similarity of fungal complexes of the litter and TE horizon is 0.68 and that of actinomycetes, 0.27.

Crop exposure to stress during cultivation is known to reduce the yield and to cause the release of allelotoxins from plants into soil. It was assumed that allelotoxin release may considerably affect the vegetable growth in greenhouses and that a decrease in the allelotoxin concentration in greenhouse substrates may improve the plant growth. To verify the assumptions, allelotoxicity and microbial contents were determined in greenhouse substrates in which cucumber, tomato, and pepper plants grew well or poorly. The allelotoxin content was found to be higher and the prokaryote content, lower in the substrates of poorly growing plants. The finding confirmed the assumption that allelotoxins significantly influence the cultivation of vegetables in greenhouses. Treating the plant root zone with humate solutions having a high allelotoxin absorption capacity appreciably improved the cucumber plant growth and was assumed to provide a promising means to increase the vegetable yields in greenhouses.

The effect of alkalinization of fulvic acid (FA) solutions on an increase in their optical density has been studied. To explain this phenomenon, FA particles existing in solutions at different pH have been studied by scanning electron microscopy (SEM) and scanning tunneling microscopy (STM). It has been found that an increase in pH results in a noticeable decrease in the size of the supramolecular assemblies of FA molecules from ~200 to ~100 nm. An STM study of FA samples demonstrates that FAs exist in solutions as supramolecular assemblies of several hundred nanometers in size formed by 10–20 nm FA particle molecules. The observed phenomenon has been explained using the existing ideas about the supramolecular fractal cluster organization of humic substances. The explanation states that the upper layer of F-clusters degrades to give FA particle molecules, while the cluster size is seen to decrease. The FA particle molecules cannot be detected by SEM due to their small size, but they are readily visualized by STM.

In the sor (playa) solonchaks of chloride and sulfate–chloride salinity (the content of readily soluble salts is 0.9–1.0%) in the delta of the Khara River discharging into Lake Elton, the number of mycelial actinobacteria (actinomycetes) is low ((2–3) × 10 3 CFU/g of soil). At a distance from the water’s edge, these soils are substituted for the light chestnut ones, for which an elevated number of actinomycetes (an order of magnitude higher than in the sor solonchaks) and a wider generic spectrum are characteristic. The actinomycetal complex is included the Streptomyces and Micromonospora genera, whereas in the sor solonchaks around the lake, representatives of Micromonospora were not found.

Under laboratory conditions, the spores of a xerotolerant Streptomyces odorifera strain germinated in brown semidesert soil even at extremely low soil water pressure ( P = −96.4 MPa, −964 atm, a w 0.50); the plantlets increased in length and formed mycelium, on which a new generation of spores was produced (a complete development cycle of the actinomycetes—from a spore to the formation of new spores—passed). The duration of the first cycles of the actinomycetes’ development varied from 13 days at P = −27 atm to 57 days at P = −964 atm and was directly proportional to the absolute value of the soil water pressure ( P ). In the first cycles of the actinomycetes’ development, the rate of increase of the concentration of the germinated spores and mycelium, as well as the logarithms of the mycelium-to-germinated spore concentration ratios, was inversely proportional to the logarithm of P . These relationships indicated that the energy state of the water determined its availability to soil biota and, hence, the activity of its physiological and biochemical processes.

It was found that PMMA prepared in the presence of the chain transfer agents dodecyl mercaptan and pentamethyldisilane possess noticeably better properties as a radiation resist relative to the polymer with a close molecular mass obtained in the absence of a transfer agent. By means of densitometry, GPC, calorimetry, small-angle X-ray scattering, and light scattering, it was shown that the existence of weak bonds, the narrowing of the molecular-mass distribution, and the formation of a looser supermolecular structure are responsible for the enhanced radiation sensitivity of the polymers prepared under the chain-transfer reaction conditions.

In the last decade, zero-cost metrics have gained prominence in neural architecture search (NAS) due to their ability to evaluate architectures without training. These metrics are significantly faster and less computationally expensive than traditional NAS methods and provide insights into neural architectures’ internal workings. This paper introduces epsinas , a novel zero-cost NAS metric that assesses architecture potential using two constant shared weight initialisations and the statistics of their outputs. We show that the dispersion of raw outputs, normalised by their average magnitude, strongly correlates with trained accuracy. This effect holds across image classification and language tasks on NAS-Bench-101, NAS-Bench-201, and NAS-Bench-NLP. Our method requires no data labels, operates on a single minibatch, and eliminates the need for gradient computation, making it independent of training hyperparameters, loss metrics, and human annotations. It evaluates a network in a fraction of a GPU second and integrates seamlessly into existing NAS frameworks. The code supporting this study can be found on GitHub at https://github.com/egracheva/epsinas .

Cell-based technologies are used as a therapeutic strategy in spinal cord injury (SCI). Mesenchymal stem cells (MSCs), which secrete various neurotrophic factors and cytokines, have immunomodulatory, anti-apoptotic and anti-inflammatory effects, modulate reactivity/phenotype of astrocytes and the microglia, thereby promoting neuroregeneration seem to be the most promising. The therapeutic effect of MSCs is due to a paracrine mechanism of their action, therefore the survival of MSCs and their secretory phenotype is of particular importance. Nevertheless, these data are not always reported in efficacy studies of MSC therapy in SCI. Here, we provide a review with summaries of preclinical trials data evaluating the efficacy of MSCs in animal models of SCI. Based on the data collected, we have tried (1) to establish the behavior of MSCs after transplantation in SCI with an evaluation of cell survival, migration potential, distribution in the area of injured and intact tissue and possible differentiation; (2) to determine the effects MSCs on neuronal microenvironment and correlate them with the efficacy of functional recovery in SCI; (3) to ascertain the conditions under which MSCs demonstrate their best survival and greatest efficacy.

Pain therapy has remained conceptually stagnant since the opioid crisis, which highlighted the dangers of treating pain with opioids. An alternative addiction-free strategy to conventional painkiller-based treatment is targeting receptors at the origin of the pain pathway, such as transient receptor potential (TRP) ion channels. Thus, a founding member of the vanilloid subfamily of TRP channels, TRPV1, represents one of the most sought-after pain therapy targets. The need for selective TRPV1 inhibitors extends beyond pain treatment, to other diseases associated with this channel, including psychiatric disorders. Here we report the cryo-electron microscopy structures of human TRPV1 in the apo state and in complex with the TRPV1-specific nanomolar-affinity analgesic antagonist SB-366791. SB-366791 binds to the vanilloid site and acts as an allosteric hTRPV1 inhibitor. SB-366791 binding site is supported by mutagenesis combined with electrophysiological recordings and can be further explored to design new drugs targeting TRPV1 in disease conditions. Small molecules targeting transient receptor potential (TRP) channels might be used to control pain. Here, Neuberger et al. report cryo-EM structures of human TRPV1 in the absence of added ligands or in the presence of the TRPV1-specific antagonist SB-366791, providing insights for the design of new promising analgesics.