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Magnetoreception, the ability to sense magnetic fields, is widespread in animals but remains poorly understood. The leading model links this ability in migratory birds to the photo-activation of the protein cryptochrome. Magnetic information is thought to induce structural changes in cryptochrome via a transient radical pair intermediate. This signal transduction pathway has been the subject of previous all-atom molecular dynamics (MD) simulations, but insights were limited to short timescales and equilibrium structures. To address this, we developed a non-equilibrium coarse-grained MD simulation approach, exploring cryptochrome’s photo-reduction over 20 replicates of 20 µs each. Our results revealed significant structural changes across the protein, with an overall time constant of 3 µs. The C-terminal (CT) region responded on a timescale of 4.7 µs, followed by the EEE-motif, while the phosphate binding loop (PBL) showed slower dynamics (9 µs). Network analysis highlighted direct pathways connecting the tryptophan tetrad to the CT, and distant pathways involving the EEE and PBL regions. The CT-dynamics are significantly impacted by a rearrangement of tryptophan residues in the central electron transfer chain. Our findings underscore the importance of considering longer timescales when studying cryptochrome magnetoreception and highlight the potential of non-equilibrium coarse-grained MD simulations as a powerful tool to unravel protein photoactivation reactions.

Abstract The antimicrobial resistance crisis along with challenges of antimicrobial discovery revealed the vital necessity to develop new antibiotics. Many of the animal proline-rich antimicrobial peptides (PrAMPs) inhibit the process of bacterial translation. Genome projects allowed to identify immune-related genes encoding animal host defense peptides. Here, using genome mining approach, we discovered a family of proline-rich cathelicidins, named rumicidins. The genes encoding these peptides are widespread among ruminant mammals. Biochemical studies indicated that rumicidins effectively inhibited the elongation stage of bacterial translation. The cryo-EM structure of the Escherichia coli 70S ribosome in complex with one of the representatives of the family revealed that the binding site of rumicidins span the ribosomal A-site cleft and the nascent peptide exit tunnel interacting with its constriction point by the conservative Trp23-Phe24 dyad. Bacterial resistance to rumicidins is mediated by knockout of the SbmA transporter or modification of the MacAB-TolC efflux pump. A wide spectrum of antibacterial activity, a high efficacy in the animal infection model, and lack of adverse effects towards human cells in vitro make rumicidins promising molecular scaffolds for development of ribosome-targeting antibiotics.

The solid-state photo-CIDNP (photo-chemically induced dynamic nuclear polarization) effect allows for nuclear hyperpolarization, i.e., non-Boltzmann nuclear spin population. The effect relies on the light-induced formation of a spin-correlated radical pair (SCRP) and has been observed in various photosynthetic reaction center (RC) proteins and flavin-containing light, oxygen, voltage (LOV) proteins. Both systems exhibit strongly enhanced NMR signals originating from the electron transfer partners. Here, we present experimental data on the magnetic field dependence of the 15N solid-state photo-CIDNP effect in both phototropin LOV1 C57S from Chlamydomonas reinhardtii and the bacterial photosynthetic RC from Rhodobacter sphaeroides. Using a pneumatic field-cycling system, samples containing a frozen solution of the proteins are explored between 0.25 T and 9.4 T. Both systems yield hyperpolarized 15N NMR signals across the entire magnetic field range originating from the electron transfer moieties. Also, in both systems, hyperpolarized signals from unexpected positions are detected between 1.0 T and 2.0 T: position N-1 of the flavin in the LOV1 protein and the τ-N of the axial magnesium-coordinating histidine of the donor. A first attempt to explain the occurrence of these unexpected signals based on quantum chemical calculations is presented.

Quantum biology is a modern field of research that aims to understand how quantum effects can affect the chemistry underlying various biological processes. This paper reviews several examples of biological processes where quantum effects might play a notable role. Initially, the photon capture mechanism present in vision is discussed, where the energy of the photon is used to cause conformational changes to chromophoric proteins. The second example elaborates the highly efficient energy transfer process present in photosynthesis and discusses, in particular, how the random quantum walk process may enhance the performance drastically. Subsequently, the vertebrate magnetoreception, and the possible associated role of the radical pair mechanism in the process is considered. The review concludes with the discussion of some speculative ideas of putative quantum effects arising in neural processes.

The influence of weak radio-frequency electromagnetic field (RF-EMF) on living organisms raises new concern because of the Industrial, Scientific, and Medical (ISM) frequency band at 6.78 MHz being promoted by the AirFuel Alliance for mid-range wireless power transfer (WPT) applications and product development. Human exposure to the RF-EMF radiation is unavoidable. In this study, we employed in vitro cell culture and molecular biology approach coupled with integrated transcriptomic and proteomic analyses to uncover the effects of RF-EMF on cells at molecular and cellular levels. Our study has demonstrated that weak RF-EMF is sufficient to exert non-thermal effects on human umbilical vein endothelial cells (HUVEC). Exposure of weak RF-EMF promotes cell proliferation, inhibits apoptosis and deregulates ROS balance. Alteration of several signaling pathways and key enzymes involved in NADPH metabolism, cell proliferation and ferroptosis were identified. Our current study provide solid evidence for the first time that the present safety standards that solely considered the thermal effect of RF-EMF on cell tissue are inadequate, prompt response and modification of existing Guidelines, Standards and Regulation are warranted.

DEAD-box RNA helicase Vasa is required for gonad development and fertility in multiple animals. Vasa is implicated in many crucial aspects of Drosophila oogenesis, including translation regulation, primordial germ cell specification, piRNA silencing of transposable elements, and maintenance of germline stem cells (GSCs). However, data about Vasa functions in Drosophila spermatogenesis remain controversial. Here we showed that loss-of-function vasa mutations led to failures of GSC maintenance in the testes, a severe loss of total germ cell content, and a cessation of male fertility over time. Defects in GSC maintenance in vasa mutant testes were not associated with an increasing frequency of programmed cell death, indicating that a premature loss of GSCs occurred via entering differentiation. We found that Vasa is implicated in the positive regulation of rhino expression both in the testes and ovaries. The introduction of a transgene copy of rhino, encoding a nuclear component of piRNA pathway machinery, in vasa mutant background allowed us to restore premeiotic stages of spermatogenesis, including the maintenance of GSCs and the development of spermatogonia and spermatocytes. However, piRNA-guided repression of Stellate genes in spermatocytes of vasa mutant testes with additional rhino copy was not restored, and male fertility was disrupted. Our study uncovered a novel mechanistic link involving Vasa and Rhino in a regulatory network that mediates GSC maintenance but is dispensable for the perfect biogenesis of Su(Ste) piRNAs in testes. Thus, we have shown that Vasa functions in spermatogenesis are essential at two distinct developmental stages: in GSCs for their maintenance and in spermatocytes for piRNA-mediated silencing of Stellate genes.

A CuII coordination polymer, catena-poly[[[aquacopper(II)]-bis(μ-4-aminobenzoato)-κ2N:O;κ2O:N] monohydrate], {[Cu(pABA)2(H2O)]·H2O}n (pABA = p-aminobenzoate, C7H4NO2−), was synthesized and characterized. It exhibits a one-dimensional chain structure extended into a three-dimensional supramolecular assembly through hydrogen bonds and π–π interactions. While the twinned crystal shows a metrically orthorhombic lattice and an apparent space group Pbcm, the true symmetry is monoclinic (space group P2/c), with disordered Cu atoms and mixed roles of water molecules (aqua ligand/crystallization water). The luminescence spectrum of the complex shows an emission at 345 nm, cf. 349 nm for pABAH.

Background. Modern society is characterized by the widespread use of social media, which provides users with new communication, leisure, work, and study opportunities. The growth of online communication time leads to the development of new special communicative needs. These circumstances prompted us to develop the “Questionnaire on Adolescents’ Needs to Communicate with Their Parents Online and Offline” (QANCP). Objective. We set out to study the relationship between adolescents’ hierarchy of communicative needs and the characteristics of child-parent relations by developing and testing the psychometric characteristics of the QANCP. Design. One hundred and twenty-eight teenagers (56 boys and 72 girls, age 15-17) took part in the research. The research methods included theoretical analysis, modeling, questionnaires, and statistical analysis. The tools used were: 1) the customized (authorial) “Questionnaire of adolescents’ needs to communicate with their parents online and offline” (QANCP); and 2) the Inventory of Parent and Peer Attachment (IPPA) by Armsden and Greenberg (1987) in the Sadovnikova and Eliseeva adaptation (Eliseeva, 2013). Results. The results of the qualitative research proved the acceptability of the QANCP scales. Expert assessments showed that the test had sufficient face and content validity. Statistically significant differences in the parameters measuring adolescents’ communicative needs in groups with different types of relations with their parents were established. Conclusion. Testing of the QANCP questionnaire showed that the QANCP is a valid and reliable instrument to measure adolescents’ communication with their parents in online and offline formats. It was established that there is a connection between the characteristics of child-parent relations in adolescence and the hierarchy of communication needs of “adolescent-parent” communication online and offline.

The Central Indian Ocean Basin (CIOB) is distinguished by unusually high tectonic activity, setting it apart from all other passive oceanic basins. Within the interior of the Indo-Australian lithospheric plate lies a unique area of intraplate deformation. This region is characterized by the highest recorded intraplate oceanic seismicity, with earthquake magnitudes reaching up to M = 8, abnormally high heat flow—measured to be two to four times higher than background levels for the ancient oceanic lithosphere of the Cretaceous age—and, most notably, intense folding and faulting of sediments and the basement, which are typically associated only with boundary zones of lithospheric plates. This anomalously tectonically active intraplate area was studied during regular research cruises in the 1970s–1980s, after which new conclusions were mainly drawn from satellite data modeling. Substantially new geophysical data were obtained in 2017 after a long gap. Bathymetric surveys using multibeam echosounders during the 42nd cruise of the R/V (Research Vessel) Akademik Boris Petrov and the SO258/2 cruise of the R/V Sonne provided full coverage of a large portion of the intraplate deformation area in the CIOB. This confirmed the mosaic-block structure of the intraplate deformation zone in the Central Indian Ocean Basin, consisting of numerous isometrically deformed tectonic blocks. A linear block at 0.2–0.6° S, which has a branch-like shape in plain view, is morphologically distinct from these blocks. It represents a system of structural elements of different scales (folds, flexures, ruptures), which constitute a structural paragenesis formed in the mechanical environment of a dextral transpressive tectonic setting.

Background: Antimicrobial peptides are generally considered promising drug candidates for combating resistant bacterial infections. However, the selectivity of their action may vary significantly. Natural gomesin, isolated from haemocytes of the tarantula Acanthoscurria gomesiana, demonstrates a broad spectrum of antimicrobial activities, being the most effective against pathogenic fungi. Methods: Here, we searched for variants of natural gomesin-like peptides and produced their recombinant analogs in the bacterial expression system. The antimicrobial activities of the obtained peptides were tested against a panel of bacterial and yeast strains, and their toxicity towards human cells was examined. Results: Most of the new analogs of gomesin have primary structures homologous to that of the natural gomesin; however, they have fewer amino acid residues and post-translational modifications. One of the discovered analogs, the His-rich shorter peptide from the spider Dysdera sylvatica, designated as DsGom, displays antifungal activity comparable with that of natural gomesin. In the process of the structural–functional study of DsGom, it was shown that this analog retains a basic mechanism of action similar to that of natural gomesin. The DsGom analog has a significantly better toxicity profile as compared to gomesin. At the same time, the loss of the first Arg residue reduces, but does not annul, the antifungal activity of DsGom. Moreover, the acidification of the growth medium reduces the loss of the antifungal activity of this analog. Conclusions: The discovered natural gomesin-like peptides display more selective antifungal activities as compared to gomesin. The low cytotoxicity of DsGom, combined with its high antifungal activity and stability, allows us to consider it a promising drug candidate for the treatment of fungal infections, especially those caused by fungi of the Candida genus.

The coordination environment of magneto-luminescent Dy3+-based Single-Molecule Magnets (SMM) is a crucial factor influencing both magnetic and luminescent properties. In this work, we explore how triphenylmethanolate (Ph3CO−), in combination with other ligands, can modulate the structure and, therefore, the magnetic properties of Dy3+-based SMM. Using triphenylmethanolate in combination with THF and pyridine (Py) as co-ligands, we synthesized a series of mononuclear cis-[Dy(OCPh3)2(THF)4][BPh4]·(2,6-Me2C5H3N) (1), trans-Dy(OCPh3)3(THF)2 (2), fac-Dy(OCPh3)3(py)3 (3) and dinuclear [(Ph3CO)Dy(THF){(μ2–Cl)2Li(THF)2}μ2–Cl]2 (4) complexes where the Dy3+ ion presents five- or six-coordinate geometries. Dinuclear compound 4 exhibits a genuine SMM behavior with a relatively high energy barrier of 421 cm−1, while mononuclear complexes 1–3 are field-induced SMM. These complexes also present Dy3+-characteristic luminescence, highlighting their multifunctional character.

Background: Endogenous antimicrobial peptides (AMPs) are evolutionarily ancient molecular factors of innate immunity that play a key role in host defense. The study of the diversity of animal defense peptides has important applications in the context of the growing global antimicrobial resistance. Methods: In this study using a transcriptome mining approach, we found three novel thanatin-like β-hairpin AMPs in the bean bug Riptortus pedestris, named Rip-2, Rip-3, and Rip-4. The peptides were expressed in the bacterial system, and their antimicrobial activities were evaluated both in vitro and in vivo. Results: Homologs of the discovered AMPs are widely distributed among different members of the infraorder Pentatomomorpha. Rip-2 was shown to have the most similar structure and LptA-targeting mechanism of action to those of thanatin, but the former peptides demonstrated a higher activity against key Gram-negative ESKAPE pathogens and also displayed a significant efficacy in a lethal model of septicemia caused by E. coli in mice at daily doses greater than 5 mg/kg. In contrast, Rip-3 and Rip-4 peptides caused bacterial membrane damage, did not induce bacterial resistance, and exhibited a strong selectivity against Bacillus and Mycobacterium spp. Conclusions: This study extends the knowledge of the structure and functions of insect host defense AMPs. Each of the novel β-hairpin peptides has a potential to be a template for the development of selective antibiotic drugs.

The article presents the description of three clinical cases of the successful treatment of toe onychomycosis and athlete’s foot of various etiologies using 5% amorolfine antifungal nail lacquer. The first case: a 31-year-old woman was diagnosed with white superficial onychomycosis of great toe caused by Trichophyton rubrum. The treatment with 5% amorolfine once a week for 6 months resulted in full recovery (both mycological and clinical). The second case: a 42-year-old woman developed onychomycosis after the application of decorative coating on her nails; onychomycosis was caused by Scopulariopsis brevicaulis. She was treated with itraconazole pulse therapy and 5% amorolfine lacquer. She fully recovered. The third case: a 65-year-old man with total onychomycosis of 10 toes developed the skin mycosis of the left foot and lower third of the leg. He was prescribed a therapy with sertaconazole cream and 5% amorolfine lacquer. The use of 5% amorolfine lacquer was continued to prevent from recurrent dermatomycosis. Thus, the above mentioned cases are a good example of the advantages of using 5% amorolfine lacquer in the treatment of most toe onychomycosis types caused by any pathogens (dermatophytes, yeasts or molds).

On the example of domestic fast reactors BN-350, BN-600, BN-800, the evolution of technical solutions for the automatic protection system of sodium-water steam generators (SG APS) is analyzed. The structural diagrams and main characteristics of the SG APS equipment of listed reactors are presented. The effectiveness of the SG APS in conditions of real leaks in steam generators of BN reactors is analyzed. The issues of development and creation of the SG APS of designed BN-1200 and INU MBIR are considered.

Abstract Cryptochromes (CRYs) are a structurally conserved but functionally diverse family of proteins that can confer unique sensory properties to organisms. In the marine bristle worm Platynereis dumerilii, its light receptive cryptochrome L-CRY (PdLCry) allows the animal to discriminate between sunlight and moonlight, an important requirement for synchronizing its lunar cycle-dependent mass spawning. Using cryo-electron microscopy, we show that in the dark, PdLCry adopts a dimer arrangement observed neither in plant nor insect CRYs. Intense illumination disassembles the dimer into monomers. Structural and functional data suggest a mechanistic coupling between the light-sensing flavin adenine dinucleotide chromophore, the dimer interface, and the C-terminal tail helix, with a likely involvement of the phosphate binding loop. Taken together, our work establishes PdLCry as a CRY protein with inverse photo-oligomerization with respect to plant CRYs, and provides molecular insights into how this protein might help discriminating the different light intensities associated with sunlight and moonlight.

Water scarcity and global warming make drought-tolerant plant species more in-demand than ever. The most drastic damage exerted by drought occurs during the critical growth stages of seed development and reproduction. In the course of their evolution, plants form a variety of drought-tolerance mechanisms, including recruiting beneficial microorganisms. Legumes (one of the three largest groups of higher plants) have unique features and the potential to adapt to abiotic stress. The available literature discusses the genetic (breeding) and physiological aspects of drought tolerance in legumes, neglecting the role of the microbiome. Our review aims to fill this gap: starting with the physiological mechanisms of legume drought adaptation, we describe the symbiotic relationship of the plant host with the microbial community and its role in facing drought. We consider two types of studies related to microbiomes in low-water conditions: comparisons and microbiome engineering (modulation). The first type of research includes diversity shifts and the isolation of microorganisms from the various plant niches to which they belong. The second type focuses on manipulating the plant holobiont through microbiome engineering—a promising biotech strategy to improve the yield and stress-resistance of legumes.

Background. Information technologies of the Russian Federation Customs Authorities have been made part of the state digital economy, providing interaction between foreign trade participants and the services provided by the Customs Authorities officers. Purpose. Detection innovations of customs services and customs control of goods sent by international mail (on the example of medical preparations) Materials and methods. In the study, the authors used materials of special customs statistics reflected on the website of the Federal Customs Service of Russia, statistics of foreign economic activity reflected on the website of Rosstat, data reflected on the Federal State Unitary Enterprise Russian Post. In this work, dialectical, systemic, historical, logical, formal-legal, comparative research methods were used. Results. Processing the flow of information and revealing potential threats while moving IMPI (including medications) shall become completely automated with the help of a monitoring system, applying the machine learning technology. Conclusion. The scope of customs control exercised over the goods forwarded in IMPI shall be , on the one hand, extensive , and on the other -efficient, without placing excessive burden in the form of money and time costs on the persons involved in forwarding IMPI.

Gap junctions transmit electrical signals in neurons and serve metabolic coupling and chemical communication. Gap junctions are made of intercellular channels with large pores, allowing ions and small molecules to permeate. In the mammalian retina, intercellular coupling fulfills many vital functions in visual signal processing but is also implicated in promoting cell death after insults, such as excitotoxicity or hypoxia. Conversely, some studies also suggested a role for retinal gap junctions in neuroprotection. Recently, gap junctions were also advocated as conduits for therapeutic drug delivery in neurodegenerative disorders. This requires the permeation of rather large molecules through retinal gap junctions. However, the permeability of retinal networks for molecules >0.6 kDa has not been tested systematically. Here, we used the cut-loading method and probed gap junctional networks in the mouse retina for their permeability to cGMP and cAMP coupled to Biotin, using the well-characterized tracer Neurobiotin as control. Biotin-cGMP and -cAMP have a molecular weight of >0.8 kDa. We show that they cannot pass the gap junctions of horizontal cells but can permeate through the gap junctions of specific amacrine cells in the inner retina. These amacrine cells do not comprise AII amacrine cells and nitric oxide-releasing amacrine cells but some unknown type. In summary, we show that some retinal gap junctions are large enough to let molecules >0.8 kDa pass, making the intercellular delivery of therapeutic agents – already successfully exploited, for example, in cancer – also feasible in neurodegenerative diseases.

Background. Argentina is one of the largest and most developed socio-economic countries in Latin America. The use of modern agricultural technologies in the Argentine plains and new methods of shipping allowed Argentina to start exporting agricultural products to Europe. A series of commodity booms enriched Argentina and made it one of the largest economies in the world at the beginning of the 20th century. Purpose is to analyze and identify problems and prospects for the development of the agricultural structure in Argentina. Materials and methods. In the study, the authors used analytical materials of the UN Economic Commission and other international organizations on the countries of Latin America, reviews and reports of the Central Bank, the Institute of Statistics, the Ministry of Economy and Public Finance, the Ministry of Foreign Affairs. In this work, dialectical, systemic, historical, logical, formal-legal, comparative research methods were used. Results. Due to the abundance of appropriate land and natural resources, the favorable climate in most of the country and the generally low activity of pests, agricultural in Argentina is not particularly limited by natural conditions. However, there are a number of other factors that prevent Argentine farmers from fully operating as efficiently as possible. Conclusion. Argentina’s agro-industrial policy is quite contradictory. Despite the development of digital services and modern information technologies to support agricultural producers, the introduction of progressive export support programs, a fairly powerful infrastructure throughout the entire production cycle of agricultural products, the Argentine government from time to time resorts to using serious export barriers to maintaining the domestic market, which in general affects the Agar sector is not always positive.

Education is a pivotal pillar in modern society, and technology has brought about major changes in how students learn. Online learning is becoming an increasingly popular form of education, especially since the coronavirus disease (COVID-19) pandemic broke out. However, the challenge of maintaining student engagement and motivation in online learning environments remains a concern for many educators. This is where the concept of gamification erupts as an innovative solution to this problem. This study aimed to examine the effect of case and project-based gamification models on student engagement and academic achievement in online learning in tertiary institutions. Quasi-experimental post-test only non-equivalent control group design was chosen as the method of this research. The subjects of this study were 117 students from Universitas Pendidikan Ganesha. The instrument used to measure student engagement was a questionnaire developed by researchers with reference to the online student engagement (OSE) indicator; meanwhile, an objective test was to assess student academic achievement. The data were analyzed using a one-way multivariate analysis of variance (MANOVA) technique. The study results show significant differences in student engagement and academic achievement between groups of students taught using case and project-based gamification models and direct e-learning models. Case and project-based gamification models used in online learning were effective in increasing student engagement and student academic achievement.

The rise in the number of Cesarean sections (CS) worldwide has increased the incidence of the placenta accreta spectrum disorders in the past years. About 5% of patients undergoing a CS develop placenta percreta. A 30-year-old woman, G2P1 with previous uncomplicated CS delivery had an elective CS delivery at 37w6d. The delivery was complicated by a substantial hemorrhage. On emergency laparotomy a placenta percreta was seen in the broad ligament, which could not be removed surgically. Embolization was performed with Gelfoam particles until stasis in the right uterine artery with placement of a coil. Patient discharge was 12 days after intervention. Emergency embolization is an effective treatment in bleeding complications due to placenta percreta at partus.

The relevance. In recent years, in addition to the direct extraction of natural or associated petroleum gases from the subsoil, it is necessary to prepare them, ensure commercial quality, in particular, remove moisture, higher C2+ hydrocarbons and other by-product gases that adversely affect the technical and economic performance of plants and contribute to the formation of crystalline hydrates. Due to the high quality requirements for treated natural gas and moisture content growth to increase the profitability of production, gas treatment technologies are constantly being improved and updated, including the absorption method of natural gas drying. Purpose: to substantiate the effectiveness of the use of triethylene glycol as an absorbent in preparation of natural gas by the absorption method at the existing integrated natural gas treatment plant. Object: complex natural gas treatment unit. Method: simulation of moisture absorption from natural gas in the UniSim Design software package. Results. The influence of pressure and temperature, two absorbents: diethylene glycol and triethylene glycol, on the efficiency of gas treatment on the model of a natural gas treatment plant, an operating gas field, has been studied. The optimal temperature and pressure are selected, at which moisture absorption from gas will most effectively take place at decreasing pressure of the input raw material. It is shown that when triethylene glycol is used as an absorbent, the energy consumption for gas compression, its cooling before the absorber, and the consumption of the desiccant are significantly reduced compared to diethylene glycol.

Marine fish migrate long distances up to hundreds or even thousands of kilometers for various reasons that include seasonal dependencies, feeding, or reproduction. The ability to perceive the geomagnetic field, called magnetoreception, is one of the many mechanisms allowing some fish to navigate reliably in the aquatic realm. While it is believed that the photoreceptor protein cryptochrome 4 (Cry4) is the key component for the radical pair-based magnetoreception mechanism in night migratory songbirds, the Cry4 mechanism in fish is still largely unexplored. The present study aims to investigate properties of the fish Cry4 protein in order to understand the potential involvement in a radical pair-based magnetoreception. Specifically, a computationally reconstructed atomistic model of Cry4 from the Atlantic herring (Clupea harengus) was studied employing classical molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) methods to investigate internal electron transfers and the radical pair formation. The QM/MM simulations reveal that electron transfers occur similarly to those found experimentally and computationally in Cry4 from European robin (Erithacus rubecula). It is therefore plausible that the investigated Atlantic herring Cry4 has the physical and chemical properties to form radical pairs that in turn could provide fish with a radical pair-based magnetic field compass sensor.

Capitellacin is the β-hairpin membrane-active cationic antimicrobial peptide from the marine polychaeta Capitella teleta. Capitellacin exhibits antibacterial activity, including against drug-resistant strains. To gain insight into the mechanism of capitellacin action, we investigated the structure of the peptide in the membrane-mimicking environment of dodecylphosphocholine (DPC) micelles using high-resolution NMR spectroscopy. In DPC solution, two structural forms of capitellacin were observed: a monomeric β-hairpin was in equilibrium with a dimer formed by the antiparallel association of the N-terminal β-strands and stabilized by intermonomer hydrogen bonds and Van der Waals interactions. The thermodynamics of the enthalpy-driven dimerization process was studied by varying the temperature and molar ratios of the peptide to detergent. Cooling the peptide/detergent system promoted capitellacin dimerization. Paramagnetic relaxation enhancement induced by lipid-soluble 12-doxylstearate showed that monomeric and dimeric capitellacin interacted with the surface of the micelle and did not penetrate into the micelle interior, which is consistent with the “carpet” mode of membrane activity. An analysis of the known structures of β-hairpin AMP dimers showed that their dimerization in a membrane-like environment occurs through the association of polar or weakly hydrophobic surfaces. A comparative analysis of the physicochemical properties of β-hairpin AMPs revealed that dimer stability and hemolytic activity are positively correlated with surface hydrophobicity. An additional positive correlation was observed between hemolytic activity and AMP charge. The data obtained allowed for the provision of a more accurate description of the mechanism of the oligomerization of β-structural peptides in biological membranes.

Link for citation: Liintin I.A., Erofeev V.I. Modernization of natural gas treatment. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 6, рр.126-133. In Rus. The relevance. Most of the existing fields in the Russian Federation are at the last stage of development. They are characterized by low wellhead pressures, increase in water cut, as well as a large amount of mechanical impurities. These factors have a detrimental effect on the technical and economic performance of the installations, as well as on the further transport of gas through the main gas pipelines. As a result, there is an urgent need to create new efficient technologies in the preparation of natural and associated petroleum gases. In addition to creating new technologies, it is possible to upgrade the existing well production facilities or change process parameters. The main aim: to modernize the current technological scheme of natural gas treatment. Object: complex gas treatment plants of gas fields. Method: modeling with a software package «UniSim Design». Results. It was calculated and shown how much of the hydrate formation inhibitor must be supplied to the gas pipeline during transportation from a cluster of gas wells to a complex gas treatment unit. The dew point temperatures were calculated before and after the upgrade of the inlet separator, as well as the percentage of moisture in natural gas before and after the upgrade of the gas treatment unit. If the wellhead and reservoir pressures drop significantly, it is necessary to carry out a general reconstruction of fields, prefabricated networks, it is possible to combine fields, install modular compressor stations, since the pressure and amount of gas for booster compressor stations will not be enough. In this regard, supersonic separation is the most promising method for separating and purifying gas condensate mixtures from moisture and acid gases. After replacing the separator with a 3S-separator in the complex natural gas purification unit, the dew point temperature of the commercial gas decreased. Gas pressure at the outlet of the 3S-separator has values corresponding to the process mode of absorber operation and the amount of separated moisture and liquid, in percentage terms, will increase.

The relevance. Today, the Russian Federation is increasing the pace of natural gas production by introducing new gas fields. But in addition to new ones, there are developed fields, most of which are at the last stage of development, that is, in a period of declining production. The gas produced from these fields is characterized by low reservoir pressures, high moisture content and mechanical impurities compared to the initial (design) values. The presence of moisture and mechanical impurities adversely affects its further processing and transportation. As a result, when reaching the required values of the industry standard, problems may arise during gas treatment by absorption or adsorption dehydration of natural gas, as well as problems associated with further gas transportation through pipelines. Therefore, the study and comparison of these two technological processes for natural gas preparation are relevant today, since many industrial gas production enterprises use these two processes of gas preparation. The main aim of the research is theoretical analysis of natural gas preparation by two typical processes: absorption and adsorption; selection of the most efficient and cost-effective processes from the point of view of industrial scale in the conditions of gas fields of oil and gas enterprises of the Russian Federation. Results. The authors carried out the review of two processes for drying natural gas by absorption and adsorption from moisture and mechanical impurities and considered the features of two processes, namely the properties of absorbents, adsorbents, typical schemes, foreign experience, as well as their advantages and disadvantages.

Abstract Background Altered neuronal excitation–inhibition (E–I) balance is strongly implicated in ASD. However, it is not known whether the direction and degree of changes in the E–I ratio in individuals with ASD correlates with intellectual disability often associated with this developmental disorder. The spectral slope of the aperiodic 1/f activity reflects the E–I balance at the scale of large neuronal populations and may uncover its putative alternations in individuals with ASD with and without intellectual disability. Methods Herein, we used magnetoencephalography (MEG) to test whether the 1/f slope would differentiate ASD children with average and below–average (

Marine polychaetes represent an extremely rich and underexplored source of novel families of antimicrobial peptides (AMPs). The rapid development of next generation sequencing technologies and modern bioinformatics approaches allows us to apply them for characterization of AMP-derived genes and the identification of encoded immune-related peptides with the aid of genome and transcriptome mining. Here, we describe a universal bioinformatic approach based on the conserved BRICHOS domain as a search query for the identification of novel structurally unique AMP families in annelids. In this paper, we report the discovery of 13 novel BRICHOS-related peptides, ranging from 18 to 91 amino acid residues in length, in the cosmopolitan marine worm Heteromastus filiformis with the assistance of transcriptome mining. Two characteristic peptides with a low homology in relation to known AMPs—the α-helical amphiphilic linear peptide, consisting of 28 amino acid residues and designated as HfBRI-28, and the 25-mer β-hairpin peptide, specified as HfBRI-25 and having a unique structure stabilized by two disulfide bonds—were obtained and analyzed as potential antimicrobials. Interestingly, both peptides showed the ability to kill bacteria via membrane damage, but mechanisms of their action and spectra of their activity differed significantly. Being non-cytotoxic towards mammalian cells and stable to proteolysis in the blood serum, HfBRI-25 was selected for further in vivo studies in a lethal murine model of the Escherichia coli infection, where the peptide contributed to the 100% survival rate in animals. A high activity against uropathogenic strains of E. coli (UPEC) as well as a strong ability to kill bacteria within biofilms allow us to consider the novel peptide HfBRI-25 as a promising candidate for the clinical therapy of urinary tract infections (UTI) associated with UPEC.

The purpose of the review was to systematize the available data on the epidemiology and diagnosis of the metabolic syndrome (MetS) in polycystic ovary syndrome (PCOS). The information search was conducted using Internet resources (PubMed, EMBASE, Google Scholar, E-Library) and literature sources for the years 2000-2020. The modern studies indicate that the prevalence of metabolic disorders varies in groups of women with different PCOS phenotypes. Numerous risk factors in PCOS lead to a significant increase in risk for cardiovascular diseases. Patients with PCOS diagnosed according to AE-PCOS Society criteria have the most severe metabolic features and risk of cardiovascular disease. Hyperandrogenism in PCOS is closely related to the aggravation of abdominal obesity, and together with insulin resistance forms the metabolic core for the development of cardiovascular diseases.

The paper is aimed at studying approaches to measuring poverty and the green economy, and conducting an empirical analysis of the relationship between the poverty rate and the factors of the green economy for the countries of the European Union. The authors identify trends in the formation of a new model of environmentally sustainable development in these countries. An empirical correlation and regression model is developed, which describes, along with macroeconomic factors, the impact of green economy factors on the level of poverty risk in the EU countries. The assessment of the model specification based on panel data of the countries of the European Union shows a negative relationship between the share of renewable energy and labor productivity on the one hand and the level of poverty risk on the other hand. This indicates the need for further development of green economy in the EU countries countries.

Study design Retrospective analysis of a single-center cohort of patients with pyogenic vertebral osteomyelitis. The purpose of the study was to review risk factors for perioperative complications and recurrences in patients diagnosed with hematogenous pyogenic vertebral osteomyelitis. Material and methods 141 inpatient records of hematogenous pyogenic vertebral osteomyelitis were reviewed at the Regional Clinical Hospital No. 2, Tyumen. Patients who developed complications, neurological deficits and recurrences were assigned to A group (n = 66), and those who did not included in B group (n = 75). Results Perioperative complications, recurrences, risk factors and neurological disorders that could develop with different treatment methods were explored. There was a greater risk of recurrences and a lower rate of neurological complications seen in chronic cases and drug addicts. There was a lower risk of intra- and postoperative complications seen in thoracic spine involvement, a greater risk of neurological deficit with involved cervical spine and a lower risk in the lumbar spine involvement. There was a lower risk of neurological disorders in type A and type B disorders, and a greater risk in type C disorders as categorized by E. Pola. There were no differences in recurrence rates among different types of involvement. HIV did not increase the risk of complications and relapses. Surgical site infection developed in 8.1 % cases of transpedicular fixation and in 6.9 % following ventral interventions. No correlation was observed between the recurrence and complication rate and the surgical methods used. Overall, recovery or stable remission was achieved in 88.6 % of cases after treatment of relapses. Conclusion Recurrences and complications were primarily caused by delayed diagnosis, co-morbidities and neurological deficits. No correlation was observed between the recurrence and complication rate and the surgical methods used. There was a greater risk of recurrences and a lower rate of neurological complications seen in chronic cases and drug addicts. Neurological disorders are common for cervical spine disorders. The risk of complications was dependent on the type of involvement as categorized by E. Pola. There was a lower risk of neurological disorders in type A and B disorders and a statistically greater risk in type C disorders.

Background. ASEAN currently forms a solid economic bloc with a combined GDP of US $ 3 trillion, a relatively high share of agriculture in GDP (11.3% in 2010-2020) and an expanding agri-food market based on changing conditions. global and regional trade patterns. Purpose. It consists in analyzing and identifying the problems of agri-food exports of the states that are members of the Association of Southeast Asian Nations (ASEAN). Materials and methods. The research is based on the Declaration on the Establishment of ASEAN (Signed in Bangkok on August 08, 1967), statistics from the Food and Agriculture Organization of the United Nations, ASEAN, and the World Trade Center. In this work, dialectical, systemic, logical research methods were used. Results. As a result of the analysis carried out in the article on agri-food exports by product, it was revealed that animal, vegetable fats and oils are the most important agricultural products of the ASEAN countries, providing a quarter of regional and more than a third of world exports. Conclusion. The agro-export policy of the ASEAN countries is largely fragmented. This is mainly due to the internal differences between the states that make up this bloc.

Neurophysiological studies suggest that abnormal neural inhibition may explain a range of sensory processing differences in autism spectrum disorders (ASD). In particular, the impaired ability of people with ASD to visually discriminate the motion direction of small-size objects and their reduced perceptual suppression of background-like visual motion may stem from deficient surround inhibition within the primary visual cortex (V1) and/or its atypical top-down modulation by higher-tier cortical areas. In this study, we estimate the contribution of abnormal surround inhibition to the motion-processing deficit in ASD. For this purpose, we used a putative correlate of surround inhibition–suppression of the magnetoencephalographic (MEG) gamma response (GR) caused by an increase in the drift rate of a large annular high-contrast grating. The motion direction discrimination thresholds for the gratings of different angular sizes (1° and 12°) were assessed in a separate psychophysical paradigm. The MEG data were collected in 42 boys with ASD and 37 typically developing (TD) boys aged 7–15 years. Psychophysical data were available in 33 and 34 of these participants, respectively. The results showed that the GR suppression in V1 was reduced in boys with ASD, while their ability to detect the direction of motion was compromised only in the case of small stimuli. In TD boys, the GR suppression directly correlated with perceptual suppression caused by increasing stimulus size, thus suggesting the role of the top-down modulations of V1 in surround inhibition. In ASD, weaker GR suppression was associated with the poor directional sensitivity to small stimuli, but not with perceptual suppression. These results strongly suggest that a local inhibitory deficit in V1 plays an important role in the reduction of directional sensitivity in ASD and that this perceptual deficit cannot be explained exclusively by atypical top-down modulation of V1 by higher-tier cortical areas.