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A mucocele of the appendix is a cystic formation of the appendix, the lumen of which is filled with mucin of varying consistency. There are benign and malignant forms of the disease. Its pathogenesis varies depending on the etiology and has not yet been fully studied. The clinical picture of this disease is nonspecific and there are difficulties in preoperative diagnosis. The purpose of the study is to present a rare clinical case of mucocele of the appendix, as well as literature data on this pathology. Successful treatment of a patient with appendix mucocele, an atypical location of the tumor was demonstrated. Based on the results of intraoperative express biopsy, as well as postoperative pathomorphological examination, surgical intervention was carried out to the required extent and with a favorable prognosis for the patient’s future life. Choosing the right method of surgical treatment allows you to avoid dangerous complications, such as the development of mucinous cystadenocarcinoma and pseudomyxoma peritonei. When performing surgery, it is necessary to be guided by the principles of safety from the patient’s point of view and not be afraid of performing access conversion.

The diversity of geographically distributed human populations shows considerable variation in external and internal traits of individuals. Such differences are largely attributed to genetic adaptation to various environmental influences, which include changes in climatic conditions, variations in sleep and wakefulness, dietary variations, and others. Whole-genome data from individuals of different populations make it possible to determine the specific genetic sites responsible for adaptations and to further understand the genetic structure underlying human adaptive characteristics. In this article, we searched for signals of single nucleotide polymorphisms (SNPs) under selection pressure in people of different populations. To identify selection signals in different population groups, the PER1, PER2 and PER3 genes that are involved in the coordination of thermogenic functions and regulation of circadian rhythms, which is directly reflected in the adaptive abilities of the organism, were investigated. Data were analyzed using publicly available data from the 1000 Genomes Project for 23 populations. The Extended Haplotype Homozygosity Score statistical method was chosen to search for traces of selection. The comparative analysis performed identified points subject to selection pressure. The SNPs were annotated through the GWAS catalog and manually by analyzing Internet resources. This study suggests that living conditions, climate, and other external factors directly influence the genetic structure of populations and vary across races and geographic locations. In addition, many of the selection variants in the PER1, PER2, PER3 genes appear to regulate biological processes that are associated with major modern diseases, including obesity, cancer, metabolic syndrome, bipolar personality disorder, depression, rheumatoid arthritis, diabetes mellitus, lupus erythematosus, stroke and Alzheimer’s disease, making them extremely interesting targets for further research aimed at identifying the genetic causes of human disease.

The article presents a detailed analysis of clinical observation of primary diffuse large B-cell lymphoma of the adrenal glands, a rare disease affecting less than 1% of patients with non-Hodgkin’s lymphomas. It describes the case of a 46-year-old man hospitalized with progressive limb paralysis, later diagnosed as paraneoplastic polyradiculoneuropathy associated with bilateral adrenal lymphoma. The diagnostic challenges of this pathology, including ambiguous imaging results and the need for histological verification to confirm the diagnosis are discussed. Special attention is paid to the uniqueness of clinical manifestations and the importance of early symptom recognition to improve prognostic outcomes in highly aggressive forms of the disease. The necessity of multidisciplinary approach in managing such patients with the participation of oncologists, endocrinologists, and neurologists to optimize diagnostic and therapeutic processes is also emphasized.

The article presents the results of observations of variations in magnetic induction using magnetomodulation sensors, which made it possible to register the signals of electromagnetic (EM) emission in the range of 0.01–200 Hz generated by rock samples under fast and slow uniaxial loading in laboratory experiments. The description of the equipment and measurement techniques used in the experiments is given. At two modes of loading rock samples differences in EM emission signals reflecting the peculiarities of the development of their destruction processes are found. It is shown that during the destruction of rock samples, the amplitude-frequency spectrum of magnetic field components clearly reveals the contribution of low-frequency harmonics, which is mainly concentrated in the frequency range below 15 Hz. It is established that magnetomodulation sensors have sufficient sensitivity and resolution to observe and register EM emission signals in the frequency range of 0.01–200 Hz, manifested during the destruction of rock samples in the process of their loading.

New measurements of the T20 component of tensor analyzing power in the reaction γd→ppπ− for photon energies 400−700 MeV are presented. The experiment was carried out on an internal tensor-polarized gas deuterium target of the VEPP-3 electron storage ring in 2023 with the use of tagged quasi-real photons and two-proton coincidence. For determination of T20, the asymmetry caused by a change of the sign of the tensor polarization of the deuteron target was measured. The new data are compared with the results of theoretical calculations based on the quasi-free approximation including πN and NN rescattering effects.

Background. Rectal fistula is a common anorectal disease of a benign nature, which is a pathological canal between the perianal skin and the rectum. Treatment of rectal fistulas is only possible through surgery. The type of surgical intervention depends on the type of fistula, its topography relative to the fibers of the anal sphincters, length, as well as additional complicating factors such as the presence of scar tissue in the anal canal, branched fistulous tracts and purulent cavities. Materials and methods. In the scientific literature one can find many methods of surgical treatment of complex rectal fistulas, but the statistical results are disappointing - relapses of the disease reach 90%, and postoperative insufficiency of the anal sphincter - 50%. Results and conclusions. This article presents a clinical case of the successful use of a combination of new methods of surgical treatment of a pararectal fistula, and also reflects the dynamics of postoperative observation of the patient for 12 months. The demonstrated combined method of surgical treatment of a patient with a complex high transsphincteric pararectal fistula is sphincter-preserving, and the results of surgical treatment showed its effectiveness in terms of the development of disease relapse.

In the present paper, the research of the processes of mixture formation is carried out using the method of transportation of light petroleum products — sequential pumping by direct contact. Modeling of the processes of mixture formation is carried out taking into account the influence of parametric factors. This paper is based on a previously published work on non-isothermal pumping of petroleum products in a pipeline. It is also worth noting that in this work, a mathematical model has been finalized to consider the increase in accuracy, namely, accounting in a telescopic pipeline. To perform numerical simulation, a software package was developed that is capable of not only modeling and calculating the parameters of the petroleum product pipeline operation in real time, followed by graphical visualization, but also comparing the obtained data with the real data processed by operators at industrial facilities.

The purpose of this study was to establish electrophysiological markers of archers’ shot accuracy by correlations between performance and electroencephalogram (EEG) power parameters in athletes of different ranks compared. Materials and methods. The research involved 20 archers shooting the classic bow, who were divided into two groups of 10 subjects each by sports rank: Candidate for Master of Sport and First-Class Sportsman. EEG was recorded using the Encephalan-EEGR-19/26 device (Medikom MTD, Taganrog) in 19 leads according to the 10–20 system. Reference electrodes were placed on the earlobes. Results. It was found that shot accuracy of high-level archers (Candidate for Master of Sport) is marked by an increase in alpha and theta EEG power in the occipito-temporal-frontal regions of the left hemisphere during the preparatory phases of the exercise, and then, by the dissociation of the powers of these frequency ranges while aiming. In contrast, shot accuracy of lower level archers is characterized by a decrease in the power of the main rhythm in the left temporal lead during the first phase of the shot. In the total sample of athletes (regardless of rank) no significant correlations were found in any of the 3365 cases of evaluation of this analytical parameter. Thus, the electrophysiological markers of bow shot accuracy differ between Candidates for Master of Sport and First-Class Sportsmen. The sevenfold greater number of significant correlations (p < 0.05) between EEG parameters and shot accuracy of Candidates for Master of Sport compared to First-Class Sportsmen indicates a high level of development of the Bow Shot functional system of purposeful movements as the skill improves, as well as testifies to the synergism of physiological processes when performing the exercise by Candidates for Master of Sport. The established facts will expand coaches’ physiological understanding of the mechanism of purposeful movements in order to objectively predict sports results.

Relevance. The need to maintain the temperature regime of product pumping under increasingly complex conditions of pipeline routes by reducing heat losses of oil and petroleum product pipelines, as well as expanding the scope of application of anti-turbulence additives. Aim. To determine the effect of anti-turbulence additives on heat and hydraulic losses in the pipeline and to propose cost-effective ways to use additives when pumping through pipelines. Objects. Heat and hydraulic losses in pipelines pumping oil and oil products. Methods. Mathematical analysis of the influence of anti-turbulence additives on the thermohydraulic properties of the flow to assess the prospects for increasing the energy efficiency of pumping liquid through pipelines by introducing polymer additives. Results. The flow temperature was calculated using anti-turbulence additive depending on its concentration and efficiency, taking into account the dependence of the properties of the pumped product on temperature. The authors have constructed the graphic dependences of the economic components of heat and hydraulic losses on the concentration of anti-turbulence additives. The economic feasibility of the decision was estimated in terms of calculating the difference in pumping costs with and without anti-turbulence additives. The authors identified the relationship between the impact of losses from friction heat and heat exchange with the environment on heat losses, and analyzed the change in these parameters after the introduction of anti-turbulence additives. For the pipeline under consideration, the parameters of which correspond to standard pumping ones, the сonclusions were drawn on the predominance of the contribution of the additive hydraulic efficiency over the thermal one. This indicates the advisability of using an anti-turbulence additive as an agent for reducing heat losses at high values of the efficiency of the polymer additive, however, the overall economic efficiency is maximum at lower concentrations of the agent. The authors constructed a planar graph reflecting the dependence of the temperature at the end of the pipeline section on two coordinates: the length of the section and the hydraulic efficiency of the introduced additive.

Atherosclerosis is the mechanistic basis of cardiovascular disorders manifested by damage to the walls of the aorta, coronary, cerebral and peripheral arteries, leading to the development of acute or chronic ischemia of internal organs and tissues. This publication describes a case of spontaneous atherosclerotic lesion of the aorta with the formation of a dissecting aneurysm in an African green monkey male. The ancestors were introduced from Ethiopia and Europe. The case monkey was housed as a family group in an outdoor enclosure with attached smaller room equipped with heating system. It lived 16.4 years. Pathological diagnosis was established through complete autopsy and histopathology. Main disease was chronic atrophic gastroenterocolitis in exacerbation complicated with alimentary dystrophy, cachexia (brown atrophy of the myocardium, liver, skeletal muscles). The concomitant diseases: complicated atherosclerosis of the aorta, dissecting abdominal aortic aneurysm with a large cylindrical organized thrombus in the aneurysm area, stenosing atherosclerosis of the renal arteries, vascular wrinkled left kidney; focal atherosclerosis of the coronary arteries and their branches with small foci of atherosclerotic cardiosclerosis and arteriosclerosis of cerebral arteries. The revealed changes indicate a significant similarity in the pathomorphogenesis of atherosclerotic lesions in African green monkey and humans. It allows us to consider this genus of primates as a promising laboratory model for studying the pathogenesis and mechanisms of regression as well as the effectiveness of therapeutic approaches to the treatment of atherosclerosis and its complications.

Wavelet analysis algorithms in combination with thresholding procedures are widely used in nonparametric regression problems when estimating a signal function from noisy data. The advantages of these methods lie in their computational efficiency and the ability to adapt to the local features of the estimated function. It is usually assumed that the signal function belongs to some special class. For example, it can be piecewise continuous or piecewise differentiable and have a compact support. These assumptions, as a rule, allow the signal function to be economically represented on some specially selected basis in such a way that the useful signal is concentrated in a relatively small number of large absolute value expansion coefficients. Then, thresholding is performed to remove the noise coefficients. Typically, the noise distribution is assumed to be additive and Gaussian. This model is well studied in the literature, and various types of thresholding and parameter selection strategies adapted for specific applications have been proposed. The risk analysis of thresholding methods is an important practical task, since it makes it possible to assess the quality of both the methods themselves and the equipment used for processing. Most of the studies in this area investigate the asymptotic order of the theoretical risk. In practical situations, the theoretical risk cannot be calculated because it depends explicitly on the unobserved, noise-free signal. However, a statistical risk estimate constructed on the basis of the observed data can also be used to assess the quality of noise reduction methods. In this paper, a model of a signal contaminated with additive Gaussian noise is considered, and the general formulation of the thresholding problem with threshold functions belonging to a special class is discussed. Lower bounds are obtained for the threshold values that minimize the unbiased risk estimate. Conditions are also given under which this risk estimate is asymptotically normal and strongly consistent. The results of these studies can provide the basis for further research in the field of constructing confidence intervals and obtaining estimates of the convergence rate, which, in turn, will make it possible to obtain specific values of errors in signal processing for a wide range of thresholding methods.

The mechanisms of preparation and occurrence of the strongest deep-focus earthquakes with MW≥8, as well as their surface manifestations, remain insufficiently studied because of the lack of the relevant data. There are but three seismic events of this kind which have so far been instrumentally recorded. This paper describes the identification and analysis of the changes in the characteristics of modern crustal movement of the 2013, MW 8.3 Sea of Okhotsk deep-focus earthquake based on the data from long-term continuous geodetic-class GNSS stations in the Sea of Okhotsk region on the Kamchatka Peninsula, the Sakhalin Island, and the coast of the Sea of Okhotsk and the Sea of Japan. There has been found temporal stability of variations in the average annual geodetic site velocities. The coordinates of GNSS-stations do not show non-linear changes typical of strong shallow earthquakes in the initial post-seismic period. The Maxwell rheology for modeling of viscoelastic relaxation of the asthenosphere/upper mantle as a result of seismic impact allows for a first approximation to qualitatively and quantitatively reproduce the displacement patterns of GNSS-sites of the Kamchatka Peninsula observed in the initial postseismic period (2–3 years after the mainshock). After that, the model estimates of postseismic movements of the peninsula become systematically lower than the observed. The values calculated for the OKHT station motion on the western coast of the Sea of Okhotsk are in good agreement with those recorded for postseismic displacements over the entire measurement interval. The observed directions of the Sakhalin Island postseismic movements systematically deviate to the northeast from the model directions and are oriented almost orthogonally to the Kuril-Kamchatka Trench. Besides the viscoelastic relaxation process, another possible reason for this issue could be an enhanced viscous friction in the bottom of the subducting Pacific plate, leading to the intense deformation of the Sakhalin Island and the western coast of Kamchatka.

Relevance. Pipeline transportation of oil and oil products is one of the most efficient and cost-effective modes of transport in the modern world. Despite this, this type of transport can also be environmentally hazardous in case of leakages caused, for example, by corrosion, violation of operating rules, unauthorized tie-ins. Non-operational localization and liquidation of leakages and unauthorized tie-ins is often not only the cause of significant financial losses, but also accidents and pollution of the area of varying severity and scale. Nowadays, the issue of determining the leakage that has occurred and its location in the shortest possible time remains open. In this regard, the development of new and improvement of existing methods for detecting leakages and tie-ins in pipelines is an urgent task today. Aim. To study the effect of the total head shift, which occurs when taking into account the change in the power of pumping units due to product leakage, on the accuracy of determining the localization of leakage or unauthorized tie-in; to improve the existing methods for determining the leakage coordinate taking into account the change in the total head developed by the oil pumping station. Methods. Modeling the occurrence of a leakage or unauthorized tie-in with a different percentage of product losses, constructing hydraulic slope lines with leakages of varying intensity in different coordinates, a comparative analysis of the results obtained from the considered existing methods and those proposed by the authors. Results. The authors have modeled the leakages in various coordinates and determined the possibility of the proposed method operation for finding the coordinates of leakages. They calculated as well the errors in determining the location of the tie-in or leakage, depending on the pump power drops when the product flows out of the oil pipeline. The paper introduces the formula for the localization of leakages or tie-ins, considering the change in the power of pumping units and, as a result, the total head.

Introduction. Petroleum bitumen is the main component of road surfaces, which play an important role in ensuring the safety and comfort of vehicle traffic. Over time, bitumen undergoes ageing, which leads to changes in its physical and chemical properties. Such changes cause a decrease in the quality of road surfaces, deterioration of their performance characteristics and reduction of durability. The analysis of research in the field of bitumen thermal stabilization, which is of great importance for optimization of technological processes at high temperatures, was carried out. The optimal composition of modified bitumen using stearic acid, industrial oil was determined.Materials and methods. Bitumen undergoes serious changes during technological processes, during the transition from the bulk to the film state under the influence of high temperatures. Thus, thermal stability of bitumen is an important condition for preserving its quality at all stages of its life cycle. The issue of bitumen thermal stabilization with the use of stearic acid T-18 in combination with industrial oil I-20, which lead to increased resistance from external factors, is considered. To establish the degree of influence of modifying components on bitumen properties, a two-factor rotatable experiment with varying the amount of industrial oil and stearic acid additives, was performed.Results. The compositions and properties of the obtained modified bitumen were studied. The analysis of the obtained results shows that the effect of stearic acid on bitumen penetration is about 6 times higher than the effect of industrial oil, while both components together have insignificant effect on the other studied properties of bitumen.Conclusions. In order to further study thermal stability on the optimal versions of bitumen compositions, studies on mass retention of bitumen films at temperatures from 160 to 220 °C were performed. According to the obtained results, it was found that the effectiveness of stearic acid is manifested at higher temperatures and reaches values up to 25 %.

Relevance. Anomalies of the position and attachment of the colon in the abdominal cavity includes a large number of options. In some cases, the pathology is not limited exclusively to the mobility of the cecum, but is combined with a violation of the fixation of the ascending colon, the absence of attachment of the hepatic and splenic angles, omission of the right half of the colon or total colonoptosis.Results. There is surgical pathology associated with abnormal position and attachment of the circumferential intestine in the abdomen and a case of abnormal position dependency and an anomaly of the attachment of the right side of the circumferential intestine, depending on body type, which have certain clinical manifestations. Clinical manifestations of this pathology, methods of diagnosis and treatment with favorable results are described in the article. Also own surgical treatment methods depending on the anatomical variant of the pathology are presented in the article.Conclusion. The anatomical restoration of the correct position of the intestine in the abdominal cavity is operative. The proposed operation is performed taking into account the anomaly variant.

NMR spectroscopy is one of the effective methods for the study of plant raw materials, which makes it possible to identify differences in the structure and functional composition of lignins of various types of plant biomass. However, there are a number of limitations in the use of this method – in particular, the registration of NMR spectra at some nuclei (13C, 31P, etc.) usually requires considerable amount of time. This article proposes an approach to reduce the recording time of 31P NMR spectra by a factor of 17 without losing the quality of the result. With the help of this method and with the use of optimized experimental parameters, the functional group analysis of lignins of some softwood and hardwood species and herbaceous plants distributed in the European North of the Russian Federation was carried out. The types of structural units and their characteristic interstructural relationships per 100 phenylpropane units were determined by HSQC NMR. Differences in the functional composition and features of the structural organization of lignins were identified depending on the family to which the plant belongs. On the basis of the obtained array of experimental data the strategies of processing of specific types of plant raw materials were proposed. For example, lignins of the Birch and Beech families showed the largest number of β-aryl ether fragments with a free hydroxyl group in the α-position, which indicates the greater reactivity of these lignins. Accordingly, representatives of these families are priority raw materials in the development of lignin processing methods. At the same time, the structure of lignins of representatives of the Beech family proved to be the most resistant to hydrolytic degradation, which is important for lignin-directed bioprocessing concepts. Acknowledgments: This study was funded by the Russian Science Foundation (Grant project no. 22-13-20015). The work of Yuliya A. Sypalova was supported by the RFBR Grant for Postgraduate Students (Project no. 20-33-90126). The equipment of the Core Facility Center “Arktika” of the Northern (Arctic) Federal University named after M.V. Lomonosov was used. For citation: Sypalova Yu.A., Shestakov S.L., Kozhevnikov A.Yu. Functional Composition and Structural Features of Higher Plant Lignins. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 5, pp. 164–183. (In Russ.). https://doi.org/10.37482/0536-1036-2023-5-164-183