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Kidney disease has emerged as a significant global health issue, projected to become the fifth-leading cause of years of life lost by 2040. The kidneys, being highly radiosensitive, are vulnerable to damage from various forms of radiation, including gamma (γ) and X-rays. However, the effects of electron radiation on renal tissues remain poorly understood. Given the localized energy deposition of electron beams, this study seeks to investigate the dose-dependent morphological and molecular changes in the kidneys following electron irradiation, aiming to address the gap in knowledge regarding its impact on renal structures. The primary aim of this study is to conduct a detailed morphological and molecular analysis of the kidneys following localized electron irradiation at different doses, to better understand the dose-dependent effects on renal tissue structure and function in an experimental model. Male Wistar rats (n = 75) were divided into five groups, including a control group and four experimental groups receiving 2, 4, 6, or 8 Gray (Gy) of localized electron irradiation to the kidneys. Biochemical markers of inflammation (interleukin-1 beta [IL-1β], interleukin-6 [IL-6], interleukin-10 [IL-10], tumor necrosis factor-alpha [TNF-α]) and oxidative stress (malondialdehyde [MDA], superoxide dismutase [SOD], glutathione [GSH]) were measured, and morphological changes were assessed using histological and immunohistochemical techniques (TUNEL assay, caspase-3). The study revealed a significant dose-dependent increase in oxidative stress, inflammation, and renal tissue damage. Higher doses of irradiation resulted in increased apoptosis, early stages of fibrosis (at high doses), and morphological changes in renal tissue. This study highlights the dose-dependent effects of electrons on renal structures, emphasizing the need for careful consideration of the dosage in clinical use to minimize adverse effects on renal function.

Introduction. Thanks to sigillographic sources, the sigillographic map of Byzantine Taurika is constantly being refined and expanded due to the emergence of new places for detecting molybdoboulla. Today, the finds of seals can be noted not only in the Southwestern or Eastern Crimea, but also on the southern coast of the peninsula. Methods. The attraction of sigillographic data, including from underwater archaeological research, and their comprehensive analysis (stylistic, iconographic, paleographic) often sheds light on some still dark pages both in the history of Taurika and the Byzantine state as a whole. A new find of the Byzantine seal from the water area of the Crimean South Coast opens another previously unknown point near Cape Plaka, where a sigillographic monument was first discovered, and once again raises the question of the addressees of correspondence, which, as it seems, should have been directly related to the Byzantine administration. Analysis and results. According to legend, the seal belonged to an official of the first rank – patrikios Constantine, who held one of the highest civilian posts in the Byzantine capital – the position of the genikos logothetes. The stylistic features of the molybdoboulla, together with the data of written sources, give reason to date this sigillographic monument to the beginning of the last quarter of the 9th century. The discovery of a seal in the water area near Cape Plaka may probably indicate not only a ship parking in a convenient bay, but also the existence of a certain port infrastructure in the nearby coastal town (Lambat), which, judging by the seal, in one way or another should have been directly related to both the local administration apparatus and the capital’s authorities in connection with the region’s entry into the sphere of imperial influence and the subordination of Taurika to the administrative and financial institutions of the Byzantine Empire. Contribution of authors. Нistorical, sigillographic and epigraphic analysis conducted by N.A. Alekseienko; historical-topographical and archaeological survey conducted by S.V. Ivanov.

Background: Radiation-induced liver disease (RILD) is a severe complication arising from radiotherapy, particularly when treating abdominal malignancies such as hepatocellular carcinoma. The liver’s critical role in systemic metabolism and its proximity to other abdominal organs make it highly susceptible to radiation-induced damage. This vulnerability significantly limits the maximum safe therapeutic dose of radiation, thereby constraining the overall efficacy of radiotherapy. Among the various modalities, electron beam therapy has gained attention due to its ability to precisely target tumors while minimizing exposure to surrounding healthy tissues. However, despite its advantages, the long-term impacts of electron beam exposure on liver tissue remain inadequately understood, particularly concerning chronic injury and fibrosis driven by sustained oxidative stress. Objectives: to investigate the molecular and cellular mechanisms underlying the radioprotective effects of vitamin C in a model of radiation-induced liver disease. Methods: Male Wistar rats (n = 120) were randomly assigned to four groups: control, fractionated local electron irradiation (30 Gy), pre-treatment with vitamin C before irradiation, and vitamin C alone. The study evaluated the effects of electron beam radiation and vitamin C on liver tissue through a comprehensive approach, including biochemical analysis of serum enzymes (ALT, AST, ALP, and bilirubin), cytokine levels (IL-1β, IL-6, IL-10, and TNF-α), and oxidative stress markers (MDA and SOD). Histological and morphometric analyses were conducted on liver tissue samples collected at 7, 30, 60, and 90 days, which involved standard staining techniques and advanced imaging, including light and electron microscopy. Gene expression of Bax, Bcl-2, and caspase-3 was analyzed using real-time PCR. Results: The present study demonstrated that fractional local electron irradiation led to significant reductions in body weight and liver mass, as well as marked increases in biochemical markers of liver damage (ALT, AST, ALP, and bilirubin), inflammatory cytokines (IL-1β, IL-6, and TNF-α), and oxidative stress markers (MDA) in the irradiated group. These changes were accompanied by substantial histopathological alterations, including hepatocyte degeneration, fibrosis, and disrupted microvascular circulation. Pre-treatment with vitamin C partially mitigated these effects, reducing the severity of the liver damage, oxidative stress, and inflammation, and preserving a more favorable balance between hepatocyte proliferation and apoptosis. Overall, the results highlight the potential protective role of vitamin C in reducing radiation-induced liver injury, although the long-term benefits require further investigation. Conclusions: The present study highlights vitamin C’s potential as a radioprotective agent against electron beam-induced liver damage. It effectively reduced oxidative stress, apoptosis, and inflammation, particularly in preventing the progression of radiation-induced liver fibrosis. These findings suggest that vitamin C could enhance radiotherapy outcomes by minimizing liver damage, warranting further exploration into its broader clinical applications.

Aggressiveness and age of manifestation of medullary thyroid cancer depend on the risk level of germline RET mutations. For high-risk mutations, preventive thyroidectomy is recommended at young age. In recent years, endoscopic operations for thyroid cancer were introduced in clinical practice. But such experience in pediatrics is very limited. We present a case report of a male patient, 6-year-old with the high-risk germline mutation С634R in RET gene. Close relatives (mother, cousin, and native sister) of the proband, were treated for medullary thyroid cancer. Also, his grandmother on the maternal line and her native brother died at the age of 38 and 37 years because of medullary thyroid cancer progression. Since 3 years old, our patient was under regular exams. At the age of six, calcitonin level was 8 ng/mL, and no evidence of pathology on ultrasound. According to recommendations of American Thyroid Association from 2015 (ATA 2015), preventive thyroidectomy was planned. This operation was performed by transoral vestibular approach. Oral nutrition started on the first day after the operation and the patient was discharged from the hospital. No major complications were observed. Transitory paresthesia and slight edema of the submental compartment were noticed. Consider this, endoscopic operation on the thyroid gland can be performed, as a preventive procedure, for RET gene germline mutation carriers in young age. This method helps avoid scars on the skin of the anterior neck.

The investigation of the radiation effects of the atomic bombing in Hiroshima and Nagasaki has revealed concerns about the impact of the residual radioactive dust produced in the soil. Manganese-56 is one of the major radioisotopes produced by neutrons from the bomb; hence, we previously examined the biological effects of manganese dioxide-56 (56MnO2) in Wistar rats, in which significant changes were found in the lung. In the present study, ten-week-old male C57BL mice were exposed to three doses of radioactive 56MnO2, stable MnO2 particles, or external γ-rays (2 Gy) to further examine the effects of 56MnO2 in a different species. The estimated absorbed radiation doses from 56MnO2 were 26, 96, and 250 mGy in the lung. The animals were examined at 3, 14, and 70 days post exposure. Histologically, no exposure-related changes were found in the lungs of any group. However, pulmonary mRNA expression of aquaporin 1, which is a useful marker for lung pathophysiology, was significantly elevated at 14 and 70 days, although no such changes were found in the mice exposed to external γ-rays (2 Gy). These data indicated that the inhalation exposure to 56MnO2 particles, with

A boom in exploration for marine geology and ocean resources has resulted in a huge demand for radio navigation or special environment communications, in turn spurring the rapid development of portable underwater wireless communication technology. State of the art acoustic communication methods used today are plagued by substantial transmission delays, multipath effects, and doppler frequency shifts, among other challenges, thus impeding the advancement of underwater wireless communication technology. Low-frequency electromagnetic transmission has proven to be a prospective solution for underwater communication, but the conventional electrical antennas is too large for portable underwater wireless communication. Emergent magnetoelectric (ME) antennas driven by piezoelectric materials have become a promising solution for miniaturizing very low frequency (VLF) communication systems. Here, a theoretical model between the radiation performance and piezoelectric material properties of the ME antenna was conducted. Guide by the theory analysis, Pb(In1/2Nb1/2)O3Pb(Mn1/3Sb2/3)O3Pb(Zr0.49Ti0.51)O3 (PIN-PMS-PZT) piezoelectric ceramic simultaneous with high d33 and Qm (d33 ∼ 401, Qm ∼ 1510) has been designed to enhance the magnetoelectric radiation of the VLF ME antenna. The PIN-PMS-PZT based ME antenna achieves a large converse magnetoelectric response 1.78 Gs⋅cm/V in EMR, which is almost doubled to commercial PZT based ME antenna. More importantly, a VLF communication system was built based on the VLF antenna, which successfully transmitted digital signals using Amplitude-Shift-Keying (ASK) modulation. It is believed that the presented work could provide a theoretical basis and feasible technical path for the employment of ME antennas in the future.

ABSTRACTLeaders play crucial roles in their enterprises. Most modern organizations today, such as corporations and government departments, have no leaders. About 80% of all organizations have no top structures, and are run by inertia as leaderless organizations. These organizations have pretense-pseudo structures and filled roles, such as CEO, Department Head/Secretary, EVP, VP, and others, but this non-accountable system mostly harms than benefits the organization and its stakeholders. When the eventual crisis unfolds, often because the façade setup has failed to properly prepare the organization for the future, these “leaders” cut resources and lower-level roles out of the organization to continue in the downfall. Sometimes, they even sacrifice their own citizens.

Abstract Wireless communication has always been an indispensable element in the modern information‐based society. Beyond the commercial electrical antenna, very low frequency (VLF) mechanical antennas have recently become research hotspot since their combination of miniaturization and favorable radiation efficiency in lossy electrically conductive environments. However, their usage is challenged due to the relatively limited radiation capability and modulation bandwidth. This study demonstrates an improved high‐efficiency magnetoelectric (ME) mechanical antenna based on the magneto‐mechano‐electric (MME) effect, realized via the synergistic effect of piezo‐driven magnets motion and converse magnetoelectricity (ME). Converse ME coefficient and radiation measurement show that the MME antenna demonstrates superior performance over a normal ME antenna. The oscillation magnet serves as an extra vibrating magnetic dipole besides the ME composite and thus brings radiation enhancement to the mechanical antenna. Furthermore, digital signal modulations are conducted with a VLF carrier signal to enable anti‐interference and anti‐attenuation communication. In view of the exemplary demonstration, the MME effect‐based antenna is expected to provide a new strategy for mechanical antenna improvement and shows tremendous potential for conductive environments communication applications.

VAPYRIN is a plant protein required for symbiosis with arbuscular mycorrhizal fungi. Here the authors identify VAPYRIN domains that control subcellular targeting and protein-protein interactions and propose that VAPYRIN acts in the nucleus and cytoplasm to coordinate signaling and intracellular arbuscule accommodation.

This article is devoted to the theory of the converse magnetoelectric (CME) effect for the longitudinal, bending, longitudinal-shear, and torsional resonance modes and its quasi-static regime. In contrast to the direct ME effect (DME), these issues have not been studied in sufficient detail in the literature. However, in a number of cases, in particular in the study of low-frequency ME antennas, the results obtained are of interest. Detailed calculations with examples were carried out for the longitudinal mode on the symmetric and asymmetric structures based on Metglas/PZT (LN); the bending mode was considered for the asymmetric free structure and structure with rigidly fixed left-end Metglas/PZT (LN); the longitudinal-shear and torsional modes were investigated for the symmetric and asymmetric free structures based on Metglas/GaAs. For the identification of the torsion mode, it was suggested to perform an experiment on the ME structure based on Metglas/bimorphic LN. All calculation results are presented in the form of graphs for the CME coefficients.

Micronecta (Micronecta) griseola Horvath, 1899 is a representative of water bugs of the family Corixidae. It is expanding its range eastwards according to our observations in Russia. In the last decade, the species has become more common in Western Siberia.The article presents the first records of M. griseola from the territory of the Middle Urals (Russia). The distribution of the species and the features of its biology are considered.

The development of new effective and safe vasopressors is one of the ways to increase the effectiveness of the treatment of hypotensive disorders, the severe forms of which remain a common cause of death in all countries of the world. Previously, we synthesized the original compound T1059, a selective inhibitor of eNOS/iNOS which has a pronounced vasoconstrictive effect. Here we show its vasopressor activity in models of the early stage of acute hemorrhagic shock in rats and dogs, as part of preclinical studies. The results indicate NOS inhibitor T1059 as a potent long-acting vasopressor. Its single parenteral administration in sufficiently safe doses (1/50–1/9 LD10), caused in rats and dogs a rapid increase in vascular tone, accompanied by a prolonged hypertensive effect (within 90–120 min in rats, and within 115 min in dogs). The repeated administration of T1059 at low doses (1/3 of the first dose) made it possible to considerably (by at least 60 min) prolong a significant vasopressor effect. In all schemes, T1059 administration considerably inhibited the development of threatening cardiorespiratory disorders and significantly (p = 0.0026–0.0098) increased the short-term survival of experimental animals, formally extending the duration of the “golden hour” by 2 times. These data indicate that NOS inhibitors and, in particular, compound T1059, are able to create new opportunities in the treatment of hypotensive disorders, including the provision of assistance at the prehospital stage of treatment of such pathologies.

Abstract To understand the radiation effects of the atomic bombing of Hiroshima and Nagasaki among the survivors, radiation from neutron-induced radioisotopes in soil should be considered in addition to the initial radiation directly received from the bombs. 56Mn, which emits both β particles and γ-rays, is one of the dominant radioisotopes created in soil by neutrons from the bomb. Thus we investigated the biological effects of internal exposure to 56MnO2 particle in the lung of male Wistar rats comparing to the effects of external 60Co-γ irradiation. Absorbed doses of internal irradiation of lungs were between 25 and 65 mGy in 56MnO2-exposed animals, while the whole body doses were between 41 and 100 mGy. Animals were examined on days 3 and 61 after the exposure. There were no remarkable pathological changes related to 56MnO2 particle exposure. However, mRNA and protein expressions of aquaporin 5 increased significantly in the lung tissue on day 3 postexposure in 56MnO2 groups (by 1.6 and 2.9 times, respectively, in the highest dose group). Smad7 mRNA expression was also significantly elevated by 30% in the highest dose group of 56MnO2. Our data demonstrated that internal exposure to 56MnO2 induced significant biological responses including gene expression changes in the lungs, while external 60Co-γ irradiation of 2 Gy did not show any changes.

Nitric oxide (NO) is a multifunctional, gaseous signaling molecule implicated in both physiological and protective responses to biotic and abiotic stresses, including salinity. In this work, we studied the effects of 200 µM exogenous sodium nitroprusside (SNP, a donor of NO) on the components of the phenylpropanoid pathway, such as lignin and salicylic acid (SA), and its relationship with wheat seedling growth under normal and salinity (2% NaCl) conditions. It was established that exogenous SNP contributed to the accumulation of endogenous SA and increased the level of transcription of the pathogenesis-related protein 1 (PR1) gene. It was found that endogenous SA played an important role in the growth-stimulating effect of SNP, as evidenced by the growth parameters. In addition, under the influence of SNP, the activation of phenylalanine ammonia lyase (PAL), tyrosine ammonia lyase (TAL), and peroxidase (POD), an increase in the level of transcription of the TaPAL and TaPRX genes, and the acceleration of lignin accumulation in the cell walls of roots were revealed. Such an increase in the barrier properties of the cell walls during the period of preadaptation played an important role in protection against salinity stress. Salinity led to significant SA accumulation and lignin deposition in the roots, strong activation of TAL, PAL, and POD, and suppression of seedling growth. Pretreatment with SNP under salinity conditions resulted in additional lignification of the root cell walls, decreased stress-induced endogenous SA generation, and lower PAL, TAL, and POD activities in comparison to untreated stressed plants. Thus, the obtained data suggested that during pretreatment with SNP, phenylpropanoid metabolism was activated (i.e., lignin and SA), which contributed to reducing the negative effects of salinity stress, as evidenced by the improved plant growth parameters.

Orbital hemangiopericytomas (HPCs) are rare mesenchymal tumors with a high tendency to recur. Treatment options are quite limited in case of a relapse, but re-irradiation can be useful. Most of the available data limit the possibility of re-irradiation, while novel techniques (e.g., pencil beam proton therapy [PT]) open new approaches for the safe repeating of treatment. To the best of our knowledge, this is the first well-documented case of multi-times (>3) irradiation of tumors located intracranially. The case reported here describes orbital HPCs with proton irradiation performed two times since 1999 in a 30-year-old woman with a medical history as well as surgery followed by conventional radiotherapy (RT) and chemotherapy, and two times stereotactic RT (in 2009 and 2013).In 2016 the patient came to our hospital with the 3rd relapse of the tumor, located in the left orbit, with an intracranial part, involving cavernous sinus, which was close to the temporal lobe. The 4th course of irradiation was done in May to June 2016 by pencil beam PT. Radiation necrosis occurred after 2 years and was treated with bevacizumab (BVZ). Three years later, another relapse was treated with PT and BVZ. The 9-month follow-up showed complete tumor response without signs of brain toxicity. The patient died due to a brain abscess 1 year after the 5th irradiation. This case shows a possibility of irradiation, applied 5 times to the same location, with promising results and manageable toxicity.

The paper presents the results of preparing a labeled dataset from open sources for 11 object classes and the analysis of two well-known object detection methods in the task of urban electronic inventory in Saint Petersburg under the concept of Smart City methods and technologies. we proposed YOLOv4 for urban object detection such as (Windows, Doors, Adv Billboards, Ramps, etc). To do that the first step is data collection from the environment, and also data augmentation techniques are employed to generate data. Then the transfer learning method is used to train our dataset with both algorithms YOLOv3 & v4 and finally the NMS method is used to remove overlaps bounding boxes. To evaluate the performance of both methods RMSE used as a metric. The YOLOv4 method showed better results in object detecting and classifying than YOLOv3 in total and in the context of each class. Based on RMSE metric formula average classification loss after the training model for YOLOv3 is 0.66 and against for YOLOv4 is 0.33. Using YOLOv4 helped us to develop the first version of web-service for automated urban object detection and recognition in real-time that can be scaled and distributed to other districts of the city.

The analysis of the dynamics of the regional transport and logistics system of the Prydniprovsky economic region revealed many barriers to its effective functioning, which were divided into 10 groups: political, institutional, innovative, investment and financial, information, environmental, tariff, infrastructure, customs, and logistics. The forecast estimation of the indicators characterizing the development of the regional transport and logistic system in the Prydniprovsky economic region by using economic and mathematical tools was carried out, and on this basis tendencies of its functioning were revealed. It should be noted that forecast estimates should be considered forecasts-warnings. That is, provided that the insignificant level of labor productivity is maintained, as well as its reduction, the low return on capital investments in the coming years can significantly reduce the volume of transport (rail and road) in the Prydniprovsky economic region. Based on the regional development strategies of Dnipropetrovsk, Zaporizhzhia and Kirovohrad regions generalized, their shortcomings in creating a transport and logistics cluster were identified. In order to transform the regional innovation ecosystem, a conceptual approach to forming the transport and logistics cluster as an element of innovation infrastructure based on reasonable specialization was substantiated. It was proved that this structure should take the form of a partnership of business structures, research institutions, higher education institutions, institutions of logistics and innovation infrastructure, and government agencies. The structural scheme of interaction between the transport and logistics cluster and the innovation ecosystem was proposed to achieve the strategic goal of "Innovative development of the region on the basis of smart specialization" while implementing the strategic documents for the period till 2027. It was established that the development and implementation of basic conceptual provisions for forming a transport and logistics cluster would create appropriate conditions for increasing the volume and quality of transport and logistics services, for intensifying innovative development and implementing a qualitatively new regional pattern of sustainable development of the Prydniprovsky economic region, which must meet modern requirements for managing economic systems.

Cytotoxic and noncytotoxic CD8+ T lymphocyte responses are essential for the control of HIV infection. Understanding the mechanisms underlying HIV control in elite controllers (ECs), which maintain undetectable viral load in the absence of antiretroviral therapy, may facilitate the development of new effective therapeutic strategies.We developed an original pipeline for an analysis of the transcriptional profiles of CD8+ cells from ECs, treated and untreated progressors. Hierarchical cluster analysis of CD8+ cells’ transcription profiles allowed us to identify five distinct groups (EC groups 1–5) of ECs. The transcriptional profiles of EC group 1 were opposite to those of groups 2–4 and similar to those of the treated progressors, which can be associated with residual activation and dysfunction of CD8+ T-lymphocytes. The profiles of groups 2–4 were associated with different numbers of differentially expressed genes compared to healthy controls, but the corresponding genes shared the same cellular processes. These three groups were associated with increased metabolism, survival, proliferation, and the absence of an “exhausted” phenotype, compared to both untreated progressors and healthy controls. The CD8+ lymphocytes from these groups of ECs may contribute to the control under HIV replication and slower disease progression. The EC group 5 was indistinguishable from normal.Application of master regulator analysis allowed us to identify 22 receptors, including interferon-gamma, interleukin-2, and androgen receptors, which may be responsible for the observed expression changes and the functional states of CD8+ cells from ECs. These receptors can be considered potential targets of therapeutic intervention, which may decelerate disease progression.

This article describes GaN/AlN heterostructures for ultraviolet-C (UVC) emitters with multiple (up to 400 periods) two-dimensional (2D)-quantum disk/quantum well structures with the same GaN nominal thicknesses of 1.5 and 16 ML-thick AlN barrier layers, which were grown by plasma-assisted molecular-beam epitaxy in a wide range of gallium and activated nitrogen flux ratios (Ga/N2*) on c-sapphire substrates. An increase in the Ga/N2* ratio from 1.1 to 2.2 made it possible to change the 2D-topography of the structures due to a transition from the mixed spiral and 2D-nucleation growth to a purely spiral growth. As a result, the emission energy (wavelength) could be varied from 5.21 eV (238 nm) to 4.68 eV (265 nm) owing to the correspondingly increased carrier localization energy. Using electron-beam pumping with a maximum pulse current of 2 A at an electron energy of 12.5 keV, a maximum output optical power of 50 W was achieved for the 265 nm structure, while the structure emitting at 238 nm demonstrated a power of 10 W.

This article reports the electrospinning technique for the manufacturing of multilayered scaffolds for bile duct tissue engineering based on an inner layer of polycaprolactone (PCL) and an outer layer either of a copolymer of D,L-lactide and glycolide (PLGA) or a copolymer of L-lactide and ε-caprolactone (PLCL). A study of the degradation properties of separate polymers showed that flat PCL samples exhibited the highest resistance to hydrolysis in comparison with PLGA and PLCL. Irrespective of the liquid-phase nature, no significant mass loss of PCL samples was found in 140 days of incubation. The PLCL- and PLGA-based flat samples were more prone to hydrolysis within the same period of time, which was confirmed by the increased loss of mass and a significant reduction of weight-average molecular mass. The study of the mechanical properties of developed multi-layered tubular scaffolds revealed that their strength in the longitudinal and transverse directions was comparable with the values measured for a decellularized bile duct. The strength of three-layered scaffolds declined significantly because of the active degradation of the outer layer made of PLGA. The strength of scaffolds with the PLCL outer layer deteriorated much less with time, both in the axial (p-value = 0.0016) and radial (p-value = 0.0022) directions. A novel method for assessment of the physiological relevance of synthetic scaffolds was developed and named the phase space approach for assessment of physiological relevance. Two-dimensional phase space (elongation modulus and tensile strength) was used for the assessment and visualization of the physiological relevance of scaffolds for bile duct bioengineering. In conclusion, the design of scaffolds for the creation of physiologically relevant tissue-engineered bile ducts should be based not only on biodegradation properties but also on the biomechanical time-related behavior of various compositions of polymers and copolymers.

Development of energy-efficient and high-performance bioreactors requires progress in methods for assessing the key parameters of the biosynthesis process. With a wide variety of approaches and methods for determining the phase contact area in gas–liquid flows, the question of obtaining its accurate quantitative estimation remains open. Particularly challenging are the issues of getting information about the mass transfer coefficients instantly, as well as the development of predictive capabilities for the implementation of effective flow control in continuous fermentation both on the laboratory and industrial scales. Motivated by the opportunity to explore the possibility of applying classical and non-classical computer vision methods to the results of high-precision video records of bubble flows obtained during the experiment in the bioreactor vessel, we obtained a number of results presented in the paper. Characteristics of the bioreactor’s bubble flow were estimated first by classical computer vision (CCV) methods including an elliptic regression approach for single bubble boundaries selection and clustering, image transformation through a set of filters and developing an algorithm for separation of the overlapping bubbles. The application of the developed method for the entire video filming makes it possible to obtain parameter distributions and set dropout thresholds in order to obtain better estimates due to averaging. The developed CCV methodology was also tested and verified on a collected and labeled manual dataset. An onwards deep neural network (NN) approach was also applied, for instance the segmentation task, and has demonstrated certain advantages in terms of high segmentation resolution, while the classical one tends to be more speedy. Thus, in the current manuscript both advantages and disadvantages of the classical computer vision method (CCV) and neural network approach (NN) are discussed based on evaluation of bubbles’ number and their area defined. An approach to mass transfer coefficient estimation methodology in virtue of obtained results is also represented.

Many studies of the ME effect have been carried out in the microwave range in connection with the possibility of creating new electronic devices. One of the main microwave ME effects is the FMR line shift in an electric field, and the purpose of this article is to compare the FMR line shift in the ME structure in an electric field for a number of ferromagnetic metals, their alloys, and YIG ferrite using various piezoelectrics. This article discusses the regimes when the bias field is directed along the main axes of the magnetic component, while, as is known, the observed effect is due only to deformation. As a result of the study, ME structures with maximum and minimum microwave ME effects were found. In addition, the “substrate effect” in the piezoelectric YIG-GGG structure is considered.

The goal of this study was to determine the activity in vitro and in vivo of avarol, a sesquiterpene hydroquinone originating from the Dysidea avara sponge from the south Adriatic Sea, against different cancer cell lines and two types of mouse carcinoma. To investigate the in vitro cytotoxicity, a human cervix adenocarcinoma cell line (HeLa), human colon adenocarcinoma (LS174), human non-small-cell lung carcinoma (A549), and a normal human fetal lung fibroblast cell line (MRC-5) were used. The in vivo antitumor activity was investigated against two transplantable mouse tumors, the Ehrlich carcinoma (EC) and cervical cancer (CC-5). The effect of avarol on cancer cell survival, which was determined by the microculture tetrazolium test, confirmed a significant in vitro potency of avarol against the investigated cell lines, without selectivity towards MRC-5. The highest cytotoxicity was exhibited against HeLa cancer cells (10.22 ± 0.28 μg/mL). Moreover, potent antitumor activity against two tumor models was determined, as the intraperitoneal administration of avarol at a dose of 50 mg/kg resulted in a significant inhibition of tumor growth in mice. After three administrations of avarol, a 29% inhibition of the EC growth was achieved, while in the case of CC-5, a 36% inhibition of the tumor growth was achieved after the second administration of avarol. Therefore, the results indicate that this marine sesquiterpenoid hydroquinone could be a promising bioactive compound in the development of new anticancer medicine.

Endophytic Bacillus subtilis is a non-pathogenic beneficial bacterium which promotes plant growth and tolerance to abiotic stresses, including drought. However, the underlying physiological mechanisms are not well understood. In this study, the potential role that endogenous salicylic acid (SA) plays in regulating endophytic B. subtilis-mediated drought tolerance in wheat (Triticum aestivum L.) was examined. The study was conducted on genotypes with contrasting levels of intrinsic drought tolerance (drought-tolerant (DT) cv. Ekada70; drought-susceptible (DS) cv. Salavat Yulaev). It was revealed that B. subtilis 10-4 promoted endogenous SA accumulation and increased the relative level of transcripts of the PR-1 gene, a marker of the SA-dependent defense pathway, but two wheat cultivars responded differently, with the highest levels exhibited in DT wheat seedlings. These had a positive correlation with the ability of strain 10-4 to effectively protect DT wheat seedlings against drought injury by decreasing osmotic and oxidative damages (i.e., proline, water holding capacity (WHC), and malondialdehyde (MDA)). However, the use of the SA biosynthesis inhibitor 1-aminobenzotriazole prevented endogenous SA accumulation under normal conditions and the maintenance of its increased level under stress as well as abolished the effects of B. subtilis treatment. Particularly, the suppression of strain 10-4-induced effects on proline and WHC, which are both contributing factors to dehydration tolerance, was found. Moreover, the prevention of strain 10-4-induced wheat tolerance to the adverse impacts of drought, as judged by the degree of membrane lipid peroxidation (MDA) and plant growth (length, biomass), was revealed. Thus, these data provide an argument in favor of a key role of endogenous SA as a hormone intermediate in triggering the defense responses by B. subtilis 10-4, which also afford the foundation for the development of the bacterial-induced tolerance of these two different wheat genotypes under dehydration.

Due to how prevalent the usage of database technologies is in everyday life and related professional fields, the insufficient qualifications of specialists in relevant positions becomes an issue. The aim of this paper is to show the importance of forming individual educational routes as a factor influencing the effectiveness of training and the ability of a specialist to develop skills in professional activities. In learning SQL queries, repeatedly performing typical tasks, seeing the results, and adjusting queries accordingly, is necessary. Therefore, computer training simulators can be considered the most effective tool for learning SQL queries. This paper proposes a method for building an individual educational route for fulfilling tasks meant to train professional skills in compiling SQL queries. The task and learner models are described within the method. The A* algorithm is modified based on the proposed models, and the conditions of using it for creating an optimal individual educational route are described. Based on the theoretical study results, a computer simulator for training professional skills in writing SQL queries is implemented using the method of building individual educational routes for fulfilling tasks meant to train professional skills in writing SQL queries. Based on the analysis of the results of a test run, the conclusion is that the usage of the proposed method and the algorithm implemented in a computer simulator can be considered effective.

Mixed variational formulation of static and dynamic problems for thin-walled beams is presented. Stiffness and mass matrixes are derived from the Reissner-like functional. Shear deformation is taken into account by using Slivker’s semi-shear theory of thin-walled bars. Corresponding Euler equations are derived from the proposed mixed functional. Linear Hermite polynomials were considered as approximation for all the internal forces and displacements functions. The exact analytical solutions to some particular eigenfrequency and static problems for thin-walled beam are obtained from mixed formulation. The effect of “spurious” frequencies in thin-walled beam spectrum is discussed. Comparison of the numerical results from the mixed and classical finite element methods is presented.

Variational formulation of stability problems for thin-walled beams is presented. Geometrical stiffness matrix is derived from the stability functional. Shear deformation is taken into account by using V.I.Slivker’s semi-shear theory of thin-walled bars. Quadratic Hermite polynomials were considered as approximation for all the internal forces and displacements functions. The exact analytical solutions to some particular eigenfrequency and stability problems for thin-walled beam are obtained. The effect of «spurious» frequencies in thin-walled beam spectrum is discussed. Comparison of the numerical results from the finite element methods is presented. Approximation by quadratic functions turns out to be faster in cases where the buckling has a flexural-torsional form.

Abstract This study addresses the problem of traffic flow estimation based on the data from a video surveillance camera. Target problem here is formulated as counting and classifying vehicles by their driving direction. This subject area is in early development, and the focus of this work is only one of the busiest crossroads in city Chelyabinsk, Russia. To solve the posed problem, we employed the state-of-the-art Faster R-CNN two-stage detector together with SORT tracker. A simple regions-based heuristic algorithm was used to classify vehicles movement direction. The baseline performance of the Faster R-CNN was enhanced by several modifications: focal loss, adaptive feature pooling, additional mask branch, and anchors optimization. To train and evaluate detector, we gathered 982 video frames with more than 60,000 objects presented in various conditions. The experimental results show that the proposed system can count vehicles and classify their driving direction during weekday rush hours with mean absolute percentage error that is less than 10%. The dataset presented here might be further used by other researches as a challenging test or additional training data.

The study examines three experiments of implementing the “learning through teaching” approach combined with the development of digital technologies and explores the influence of these methods on the quality of education for undergraduate engineering students at an urban technical university in Russia. In the first experiment, small independent groups of students within the same cohort developed individual Java modules with the goal of creating an intelligent system to support solving problems using graphs. In the second experiment, each student peer-taught the topic of their choice to three other students and then administered an oral exam to these students to assess their understanding. In the third experiment, each participant selected a problem to develop a solution and recorded a video that explained this solution to other students. All recorded videos were made available to all students, and the combined collection consisted of 100 videos. During the final exam, students were randomly assigned one of these problems and had to present their solutions to the instructor. Analysis of the experiments demonstrated that integrating “learning through teaching” led to an increase in student interest in the discipline and an improvement in conceptual understanding, more so for students in the role of teacher than in the role of learner. Overall, combining pedagogical and digital technologies improved the quality of education for engineering students.

Императрица Екатерина II была вдохновительницей многих российских проектов в области исторической науки. Она и сама была историком, пусть не самостоятельным, но весьма активным. Екатерина охотно использовала историю для пропаганды собственных политических идей, но кроме того, являлась увлеченным читателем исторических сочинений. Почти все сказанное касается как российской, так и античной истории. А насколько ориентировалась императрица в истории византийской? Ей, как кажется, просто положено было ею интересоваться: с конца 1770‑х до начала 1790‑х гг. Екатерина была захвачена идеей расчленить Османскую империю и возродить Византию со столицей в Константинополе. На троне будущей империи она видела своего младшего внука, родившегося в 1779 г. и с умыслом нареченного Константином. Этот «Греческий проект», считающийся главным ориентиром российской внешней политики на протяжении 15 лет, имел значительную культурную «упаковку» в виде архитектурных проектов, поэтических и драматических произведений, картин, медалей и т. п. Но сопровождалась ли эта кампания углубленным интересом к Византии, которую Екатерина собралась возродить? Вывод автора состоит в том, что императрица не дала себе труда узнать об этой великой цивилизации практически ничего: она никому из профессиональных историков не поручила разрабатывать собственно византийскую историю в отрыве от русских сюжетов. Начав читать нашумевшую по всей Европе «Историю заката и падения Римской империи» Эдварда Гиббона, она бросила ее на изложении событий V в., то есть как раз при начале собственно Византии. В своей пьесе «Начальное управление Олега» она демонстрирует полное невнимание к византийской истории, культуре, придворному церемониалу и т. д. В своих «Записках касательно Российской истории» она допускает в «византийских» сюжетах такие огрехи, которые свидетельствуют об отсутствии живого интереса и общей картины. Лишь однажды в этом обширном сочинении в отдельно стоящем примечании встречается чрезвычайно детальный и эрудированный рассказ о византийской реалии – а именно о сфере компетенции, обмундировании и названиях должностей в варяжской гвардии императора. Таким образом, если бы Екатерине это казалось важным, она сумела бы разыскать самую исчерпывающую информацию по любому «византийскому» вопросу – но из всего византийского по-настоящему важно ей было лишь то, что касалось актуального в России норманнского спора. В остальном же Византия была ей глубоко безразлична. Можно заподозрить, что императрица ни в какой момент не относилась к «Греческому проекту» как к практической задаче по воссозданию реального государства с его особыми законами, чиновниками, территориальным делением и, главное, церковью.

The article discusses the physical foundations of the application of the linear magnetoelectric (ME) effect in composites for devices in the low-frequency range, including the electromechanical resonance (EMR) region. The main theoretical expressions for the ME voltage coefficients in the case of a symmetric and asymmetric composite structure in the quasi-static and resonant modes are given. The area of EMR considered here includes longitudinal, bending, longitudinal shear, and torsional modes. Explanations are given for finding the main resonant frequencies of the modes under study. Comparison of theory and experimental results for some composites is given.

We report on single-photon emitters for the telecommunication O-band (1260–1360 nm), which comprise an InAs/(In)GaAs quantum dot with asymmetric barriers, placed inside a semiconductor tapered nanocolumn acting as a photonic nanoantenna. The implemented design of the barriers provides a shift in the quantum dot radiation wavelength towards the O-band, while the nanoantenna collects the radiation and ensures its effective output. With non-resonant optical pumping, the average count rate of emitted single photons exceeds 10 MHz with the second-order correlation function g(2)(0) = 0.18 at 8 K.

Text analysis can help to identify named entities (NEs) of small molecules, proteins, and genes. Such data are very important for the analysis of molecular mechanisms of disease progression and development of new strategies for the treatment of various diseases and pathological conditions. The texts of publications represent a primary source of information, which is especially important to collect the data of the highest quality due to the immediate obtaining information, in comparison with databases. In our study, we aimed at the development and testing of an approach to the named entity recognition in the abstracts of publications. More specifically, we have developed and tested an algorithm based on the conditional random fields, which provides recognition of NEs of (i) genes and proteins and (ii) chemicals. Careful selection of abstracts strictly related to the subject of interest leads to the possibility of extracting the NEs strongly associated with the subject. To test the applicability of our approach, we have applied it for the extraction of (i) potential HIV inhibitors and (ii) a set of proteins and genes potentially responsible for viremic control in HIV-positive patients. The computational experiments performed provide the estimations of evaluating the accuracy of recognition of chemical NEs and proteins (genes). The precision of the chemical NEs recognition is over 0.91; recall is 0.86, and the F1-score (harmonic mean of precision and recall) is 0.89; the precision of recognition of proteins and genes names is over 0.86; recall is 0.83; while F1-score is above 0.85. Evaluation of the algorithm on two case studies related to HIV treatment confirms our suggestion about the possibility of extracting the NEs strongly relevant to (i) HIV inhibitors and (ii) a group of patients i.e., the group of HIV-positive individuals with an ability to maintain an undetectable HIV-1 viral load overtime in the absence of antiretroviral therapy. Analysis of the results obtained provides insights into the function of proteins that can be responsible for viremic control. Our study demonstrated the applicability of the developed approach for the extraction of useful data on HIV treatment.

The paper addresses, mostly with demographic tools, the rationale and consequences of the reform of Russia’s distributive pension system. Contrary to official assertions, mortality conditions do not warrant an increase of the pension age. The reference to a rapidly falling demographic support ratio as a rationale of the reform’s urgency is misleading. A rapid and large increase in the retirement age will considerably reduce the obligations of the Pension Fund of Russia, yet this will be far from enough to balance its budget. The reform creates a fundamentally new and difficult to implement task of ensuring the right to employment of persons deprived of the right to a pension. To the extent that this task can be accomplished, the Pension Fund of Russia and the State budget will be supplemented with additional revenues. At the same time, to the extent that this task remains unresolved, a social group of elderly people who are deprived of income will arise and continue to grow. For a limited time their life will be supported by unemployment benefits. Russia possesses large-scale alternative resources for resolving the pension problem, which consist, among other things, in increasing the collection of pension contributions, labor productivity and employment of the population, as well as in developing funded forms of pension insurance.

The interaction of human immunodeficiency virus with human cells is responsible for all stages of the viral life cycle, from the infection of CD4+ cells to reverse transcription, integration, and the assembly of new viral particles. To date, a large amount of OMICs data as well as information from functional genomics screenings regarding the HIV–host interaction has been accumulated in the literature and in public databases. We processed databases containing HIV–host interactions and found 2910 HIV-1-human protein-protein interactions, mostly related to viral group M subtype B, 137 interactions between human and HIV-1 coding and non-coding RNAs, essential for viral lifecycle and cell defense mechanisms, 232 transcriptomics, 27 proteomics, and 34 epigenomics HIV-related experiments. Numerous studies regarding network-based analysis of corresponding OMICs data have been published in recent years. We overview various types of molecular networks, which can be created using OMICs data, including HIV–human protein–protein interaction networks, co-expression networks, gene regulatory and signaling networks, and approaches for the analysis of their topology and dynamics. The network-based analysis can be used to determine the critical pathways and key proteins involved in the HIV life cycle, cellular and immune responses to infection, viral escape from host defense mechanisms, and mechanisms mediating different susceptibility of humans to infection. The proteins and pathways identified in these studies represent a basis for developing new anti-HIV therapeutic strategies such as new drugs preventing infection of CD4+ cells and viral replication, effective vaccines, “shock and kill” and “block and lock” approaches to cure latent infection.

We have developed an algorithm for segmentation of aerosol inhomogeneities in the registered field of lidar signal fluctuations in the atmosphere in the "Range – Time" coordinates that is based on a sliding window of a two-dimensional autocorrelation function. The obtained algorithm allows us to robustly detect aerosol inhomogeneities, which can be used in practical applications to study aerosol fields in the atmosphere and improve the accuracy of estimating the speed and direction of winds. The developed method was applied for obtaining a histogram of aerosol inhomogeneity-size distribution from 355-nm elastic lidar measurements data in the surface layer.

Modelling of tides and tsunami waves propagation is important problem for the hydraulic engineering practice since it allows to predict characteristics of these phenomena (load, values of run up and flooding zones, propagation times to structures and so on) and to make reasonable choice of design solution for coastal structures. Numerical modeling is effective way to simulate tides and tsunami waves propagation. Results of simulations of tides and tsunami waves propagation on the basis of shallow water model are presented and analyzed in the article. It was considered explicit and implicit numerical scheme for solution of shallow water model equations, which were verified on the number of experimental results including experimental data on distribution of dam-break wave propagation on a dry and sloping bottom. It is shown that the numerical data of tides in Persian Gulf are well co-ordinated with the data of tidal tables, both on time and on level of tides in various points. Numerical results of tsunami waves propagation in the Krasheninnikov Bay and Kozmino Bay are presented at various angles of tsunami at open boundary of computed area. Numerical results of tide currents for Krasheninnikov Bay are presented for various velocities of a wind. Developed programs may be used, particular, for numerical calculations of impact characteristics of tsunami waves on structures in coastal and offshore zones according requirements of Russian normative documents.

Comparing business process models is one of the most significant challenges for business and systems analysts. The complexity of the problem is explained by the fact there is a lack of tools that can be used for comparing business process models. Also there is no universally accepted standard for modeling them. EPC, YAWL, BPEL, XPDL and BPMN are only a small fraction of available notations that have found acceptance among developers. Every process modeling standard has its advantages and disadvantages, but almost all of them comprise an XML schema, which defines process serialization rules. Due to the fact that XML naturally represents hierarchical and reference structure of business process models, these models can be compared using their XML representations. In this paper we propose a generic comparison approach, which is applicable to XML representations of business process models. Using this approach we have developed a tool, which currently supports BPMN 2.0 [1] (one of the most popular business process modeling notations), but can be extended to support other business process modeling standards.

Monolayer (ML)-scale GaN/AlN multiple quantum well (MQW) structures for electron-beam-pumped ultraviolet (UV) emitters are grown on c-sapphire substrates by using plasma-assisted molecular beam epitaxy under controllable metal-rich conditions, which provides the spiral growth of densely packed atomically smooth hillocks without metal droplets. These structures have ML-stepped terrace-like surface topology in the entire QW thickness range from 0.75–7 ML and absence of stress at the well thickness below 2 ML. Satisfactory quantum confinement and mitigating the quantum-confined Stark effect in the stress-free MQW structures enable one to achieve the relatively bright UV cathodoluminescence with a narrow-line (~15 nm) in the sub-250-nm spectral range. The structures with many QWs (up to 400) exhibit the output optical power of ~1 W at 240 nm, when pumped by a standard thermionic-cathode (LaB6) electron gun at an electron energy of 20 keV and a current of 65 mA. This power is increased up to 11.8 W at an average excitation energy of 5 µJ per pulse, generated by the electron gun with a ferroelectric plasma cathode at an electron-beam energy of 12.5 keV and a current of 450 mA.

Adverse drug effects (ADEs) are one of the leading causes of death in developed countries and are the main reason for drug recalls from the market, whereas the ADEs that are associated with action on the cardiovascular system are the most dangerous and widespread. The treatment of human diseases often requires the intake of several drugs, which can lead to undesirable drug-drug interactions (DDIs), thus causing an increase in the frequency and severity of ADEs. An evaluation of DDI-induced ADEs is a nontrivial task and requires numerous experimental and clinical studies. Therefore, we developed a computational approach to assess the cardiovascular ADEs of DDIs. This approach is based on the combined analysis of spontaneous reports (SRs) and predicted drug-target interactions to estimate the five cardiovascular ADEs that are induced by DDIs, namely, myocardial infarction, ischemic stroke, ventricular tachycardia, cardiac failure, and arterial hypertension. We applied a method based on least absolute shrinkage and selection operator (LASSO) logistic regression to SRs for the identification of interacting pairs of drugs causing corresponding ADEs, as well as noninteracting pairs of drugs. As a result, five datasets containing, on average, 3100 potentially ADE-causing and non-ADE-causing drug pairs were created. The obtained data, along with information on the interaction of drugs with 1553 human targets predicted by PASS Targets software, were used to create five classification models using the Random Forest method. The average area under the ROC curve of the obtained models, sensitivity, specificity and balanced accuracy were 0.837, 0.764, 0.754 and 0.759, respectively. The predicted drug targets were also used to hypothesize the potential mechanisms of DDI-induced ventricular tachycardia for the top-scoring drug pairs. The created five classification models can be used for the identification of drug combinations that are potentially the most or least dangerous for the cardiovascular system.

We report on single photon emitters for the green-yellow spectral range, which comprise a CdSe/ZnSe quantum dot placed inside a semiconductor tapered nanocolumn acting as a multimode nanoantenna. Despite the presence of many optical modes inside, such a nanoantenna is able to collect the quantum dot radiation and ensure its effective output. We demonstrate periodic arrays of such emitters, which are fabricated by focused ion beam etching from a II-VI/III-V heterostructure grown using molecular beam epitaxy. With non-resonant optical pumping, the average count rate of emitted single photons exceeds 5 MHz with the second-order correlation function g(2)(0) = 0.25 at 220 K. Such single photon emitters are promising for secure free space optical communication lines.

The protective effects against drought stress of the endophytic bacterium Bacillus subtilis 10-4 were measured by studying the priming response in two wheat (Triticum aestivum L.)—Ekada70 (E70) and Salavat Yulaev (SY)—lines, tolerant and susceptible to drought, respectively. B. subtilis 10-4 improved germination and growth parameters under normal conditions in both cultivars with the most pronounced effect observed in cv. E70. Under drought conditions, B. subtilis 10-4 significantly ameliorated the negative impact of stress on germination and growth of cv. E70, but had no protective effect on cv. SY. B. subtilis 10-4 induced an increase in the levels of photosynthetic chlorophyll (Chl) a, Chl b, and carotenoids (Car) in the leaves of cv. E70, both under normal and drought conditions. In cv. SY plants, bacterial inoculation decreased the contents of Chl a, Chl b, and Car under normal conditions, but pigment content were almost recovered under drought stress. B. subtilis 10-4 increased water holding capacity (WHC) of cv. E70 (but did not affect this parameter in cv. SY) and prevented the stress-induced decline in WHC in both cultivars. Notably, B. subtilis 10-4 increased endogenous salicylic acid (SA) concentration in both cultivars, especially in cv. E70. Moreover, B. subtilis 10-4 reduced drought-induced endogenous SA accumulation, which was correlated with the influence of endophyte on growth, indicating a possible involvement of endogenous SA in the implementation of B. subtilis-mediated effects in both cultivars. Overall, B. subtilis 10-4 inoculation was found to increase drought tolerance in seedlings of both cultivars, as evidenced by decreased lipid peroxidation, proline content, and electrolyte leakage from tissues of wheat seedlings primed with B. subtilis 10-4 under drought conditions.

Viruses can be spread from one person to another; therefore, they may cause disorders in many people, sometimes leading to epidemics and even pandemics. New, previously unstudied viruses and some specific mutant or recombinant variants of known viruses constantly appear. An example is a variant of coronaviruses (CoV) causing severe acute respiratory syndrome (SARS), named SARS-CoV-2. Some antiviral drugs, such as remdesivir as well as antiretroviral drugs including darunavir, lopinavir, and ritonavir are suggested to be effective in treating disorders caused by SARS-CoV-2. There are data on the utilization of antiretroviral drugs against SARS-CoV-2. Since there are many studies aimed at the identification of the molecular mechanisms of human immunodeficiency virus type 1 (HIV-1) infection and the development of novel therapeutic approaches against HIV-1, we used HIV-1 for our case study to identify possible molecular pathways shared by SARS-CoV-2 and HIV-1. We applied a text and data mining workflow and identified a list of 46 targets, which can be essential for the development of infections caused by SARS-CoV-2 and HIV-1. We show that SARS-CoV-2 and HIV-1 share some molecular pathways involved in inflammation, immune response, cell cycle regulation.

This article investigates longitudinal deformation waves in physically nonlinear coaxial elastic shells containing a viscous incompressible fluid between them. The presence of a viscous incompressible fluid between the shells, as well as the influence of the inertia of the fluid motion on the amplitude and velocity of the wave, are taken into account. The mathematical model phenomenon is constructed by means of the method of two-scale asymptotic expansion. Structural damping in the shells and surrounding elastic media did not allow discovery of the exact solution of the problem of the deformation waves propagation. This leads to the need for numerical methods. A numerical study of the model constructed in the course of this work is carried out by using a difference scheme for the equation similar to the Crank−Nicholson scheme for the heat equation. In the absence of the structural damping and surrounding media influences, and under the similar initial conditions for both shells, the velocity and amplitude of the wave do not change. The result of the numerical experiment coincides with the exact solution, which is found in the case of the absence of the structural damping and surrounding media influences; therefore, the difference scheme is adequate to the generalized modified Korteweg−de Vries equations system. There is energy is transferred in the presence of the fluid, between the shells. The presence of inertia of the fluid motion leads to a decrease in the velocity of the deformation wave.

The nitrogen-fixing rhizobia in the symbiotic infected cells of root nodules are kept in membrane compartments derived from the host cell plasma membrane, forming what are known as symbiosomes. These are maintained as individual units, with mature symbiosomes having a specific radial position in the host cell cytoplasm. The mechanisms that adapt the host cell architecture to accommodate intracellular bacteria are not clear. The intracellular organization of any cell depends heavily on the actin cytoskeleton. Dynamic rearrangement of the actin cytoskeleton is crucial for cytoplasm organization and intracellular trafficking of vesicles and organelles. A key component of the actin cytoskeleton rearrangement is the ARP2/3 complex, which nucleates new actin filaments and forms branched actin networks. To clarify the role of the ARP2/3 complex in the development of infected cells and symbiosomes, we analyzed the pattern of actin microfilaments and the functional role of ARP3 in Medicago truncatula root nodules. In infected cells, ARP3 protein and actin were spatially associated with maturing symbiosomes. Partial ARP3 silencing causes defects in symbiosome development; in particular, ARP3 silencing disrupts the final differentiation steps in functional maturation into nitrogen-fixing units.

Nuclei of arbuscular endomycorrhizal fungi have been described as highly diverse due to their asexual nature and absence of a single cell stage with only one nucleus. This has raised fundamental questions concerning speciation, selection and transmission of the genetic make-up to next generations. Although this concept has become textbook knowledge, it is only based on studying a few loci, including 45S rDNA. To provide a more comprehensive insight into the genetic makeup of arbuscular endomycorrhizal fungi, we applied de novo genome sequencing of individual nuclei of Rhizophagus irregularis. This revealed a surprisingly low level of polymorphism between nuclei. In contrast, within a nucleus, the 45S rDNA repeat unit turned out to be highly diverged. This finding demystifies a long-lasting hypothesis on the complex genetic makeup of arbuscular endomycorrhizal fungi. Subsequent genome assembly resulted in the first draft reference genome sequence of an arbuscular endomycorrhizal fungus. Its length is 141 Mbps, representing over 27,000 protein-coding gene models. We used the genomic sequence to reinvestigate the phylogenetic relationships of Rhizophagus irregularis with other fungal phyla. This unambiguously demonstrated that Glomeromycota are more closely related to Mucoromycotina than to its postulated sister Dikarya.