Search

Introduction. It is generally accepted that dedifferentiated chondrosarcomas are a result of transformation of low-grade (grade I and II) malignant chondrosarcomas into sarcoma with marked signs of cellular and tissue anaplasia with more aggressive clinical progression. Morphological examination of dedifferentiated chondrosarcomas allows to detect presence of pre-existent low-grade malignant chondrosarcoma tissue. Dedifferentiated chondrosarcomas comprise about 10 % of all chondrosarcomas. Most frequently, this tumor is located in the femur, pelvic bones, and humerus. A common clinical complication of dedifferentiated chondrosarcomas is pathological fracture. This disease is characterized by more aggressive progression with unfavorable prognosis compared to conventional types of chondrosarcomas.Aim. To study in detail the data of laboratory, clinical, radiological and morphological examinations of patients with different chondrosarcoma types for refinement of the algorithm of dedifferentiated chondrosarcoma examination and diagnosis.Materials and methods. Between 2008 and 2022, data of 160 patients with chondrosarcomas of varying locations and differentiation were analyzed. Diagnosis of “cartilaginous tumor” was made in all patients after clinical and radiological exams, as well as preoperative biopsy. Diagnosis of “dedifferentiated chondrosarcoma” was made in 30 patients. Radiological exam included several methods (X-ray, X-ray computed tomography, and magnetic resonance imaging) and modes of patient examination. Morphological diagnosis included routine techniques of histological analysis with gentle decalcification and subsequent immunohistochemical (PD-L1, PU-1, CD8, CD20, Ki67, CD34) and genetic analyses (IDH1/IDH2).Results. Among 160 patients, preoperative biopsy verified the diagnosis of “dedifferentiated chondrosarcoma” only in 6 patients. In 4 patients, the possibility of chondrosarcoma transformation into poorly differentiated sarcoma of non-cartilaginous structure was suspected. At the stage of postoperative material examination, diagnosis of “dedifferentiated chondrosarcoma” was confirmed in 4 patients with suspicion of more malignant tumor transformation and newly made in 20 more patients. Female patients were a little more common (19/11). Mean patient age was 59 years. Pathological fracture at the preoperative stage was observed in 6 patients. In almost one third of the cases (36 %), decreased differentiation of chondrosarcoma compared to preoperative biopsy was observed. It is important for management of these patients that in approximately 13 % of chondrosarcoma cases, recurrence with decreased tumor differentiation is observed.Conclusion. Radical surgical resection remains the standard treatment of chondrosarcoma as the effectiveness of radio- and chemotherapy is limited though it remains important in dedifferentiated type of the disease. These circumstances lead to the use of tumor immunotherapy targeted at the search for potential use of the immune response for recognition and killing of various malignant cells including dedifferentiated chondrosarcoma. Consequently, a promising research direction is determination of the significance of tumor-associated macrophages, as well as tumor-infiltrating lymphocytes as antitumor factors and biomarkers affecting clinical and morphological characteristics of oncological diseases.

Introduction. The analytical calculation of reinforced concrete waffle slabs calls for the determination of the components of total load on joists, depending on the dimensions of spans and the rigidity of central joists. In the case of slabs having rectangular coffers of various orthogonal rigidity, this theory leads to results differing significantly from those obtained by the finite element method. The waffle slab comprises a ribbed slab, characterized by cylindrical or relative beam stiffness.Aim. This article discusses the accuracy of the calculated span bending moments in the joists of straight reinforced concrete waffle slabs using the span dimensions and relative stiffness of joists in analytical formulas.Materials and methods. The work was carried out by comparing the bending moments for joists in the central zones of straight waffle slabs obtained analytically and using the SCAD software by the finite-element method. Square or rectangular in plan, 13 slabs having different aspect ratios of waffle were considered. A T-beam and girder construction were used in the computer model.Results. The maximum deviations of the bending moments obtained by the analytical calculation from the computer-aided method amount to: -0.6% for a square slab having square coffers, from -2.8 to +2.5% for a square slab having rectangular coffers, from -6.2 to +2.0% at a span ratio of Lmax/Lmin ≤ 1.5 for a rectangular slab having rectangular coffers, and from -7.3 to +4.8% for those having square coffers. For rectangular slabs having any coffers at a span ratio of Lmax/Lmin ≥ 1.75, a computer-aided calculation revealed that the plot of bending moments in the long-side direction deviates from parabola.Conclusions. The use of the span dimensions and relative stiffness of joists in the analytical formulas for calculating straight hinge-supported reinforced concrete waffle slabs allows the values of bending moments to be obtained that are in agreement with those obtained by the finite element method.

Introduction. The analysis of analytical and computer-assisted calculations of waffle slabs shows that, depending on the established finite-element model and structure geometry, the forces in beams can vary significantly. As a rule, the analytical model is used as a reference when comparing bending moments. Examples available in the literature show that regardless of the slab geometry, the stiffness of individual central orthogonal beams or conditionally selected beams is used in the calculations when determining structural loads.Aim. In this work, the accuracy of resulting forces in the beams of straight waffle slabs was assessed using the stiffness of individual beams in the analytical calculation.Materials and methods. The work was carried out by comparing the bending moments obtained analytically and in the SCAD software by the finite-element method for beams having various stiffnesses in the central zones of straight waffle slabs. 12.0 × 12.0 m slabs square in plan having different aspect ratios of waffle were considered, as well as slabs having square 1.5 × 1.5 m waffles and different aspect ratios of spans. A T-beam-and-girder construction was used in the computer model.Results. The values of bending moments of slabs square in plan having square caissons calculated analytically and using the computer-assisted finite-element method coincide, being a particular case. The bending moments calculated analytically and using the finite-element method for rectangular slabs or slabs having rectangular caissons differ. As the ratio of the span or caisson sides increases, these deviations increase.Conclusions. In the general calculation, using the stiffnesses of individual central orthogonal beams or conditionally selected beams for the analytical determination of forces in the beams of straight waffle slabs leads to erroneous results.

Phosphaturic mesenchymal tumor inducing development of phosphopenic osteomalacia is manifested as deformations and multiple fractures of the bones which decreases patients’ quality of life and leads to disability. Insufficient awareness about this pathology among doctors and absence of symptoms allowing its diagnosis cause late diagnosis of the disease despite application of up-to-date high-tech diagnostic methods. The optimal treatment of phosphaturic mesenchymal tumors is radical resection. However, strong connection of the tumor with the surrounding tissues and, in many cases, absence of a capsule or sclerosis (if located in the bones) complicate surgery leading to high recurrence rate. Radical resection of phosphaturic mesenchymal tumors is especially complicated in cases of localization in complex anatomical areas of the lower limbs.The disease is characterized by long timespan between first clinical signs, diagnosis, and start of treatment (sometimes, several years). Diagnosis confirmation and visualization of the details of phosphaturic mesenchymal tumor requires magnetic resonance imaging. This method allows to examine connection between the tumor and surrounding tissues and the presence of a capsule. Magnetic resonance imaging also allows to accurately determine the area of surgical intervention. Radical tumor resection leads to normalization of blood and urine biochemistry in the span of several weeks. Restoration of bone density and muscle function requires 3–6 months after the operation.

The Bazhenov Formation rocks contain thin luminescent layers enriched in type I kerogen, which is unique for the bulk of the organic matter of the Bazhenov Formation of the West Siberian petroleum basin. The article provides a detailed characterization of the mineral and organic parts and proposed origin of these layers, called by the authors “alginite-rich layers”. The wide distribution of the luminescent alginite-rich layers over the central part of Western Siberia in a single stratigraphic range allows them to be used as marking horizons, as well as for assessing the thermal maturity of kerogen. This study contributes to understanding the diversity of processes that form the organic-rich deposits of the Bazhenov Formation.

Natural processes contradictive to the common organic (sedimentary and migrational) theory of oil formation were concluded to take place based on the study of the hydrocarbons-biomarkers distribution regularities at the molecular level in the dispersed organic matter of rocks, petroleum and kerogen thermolysis products.Here specific examples of the generation of oil (concentrated organic matter) directly in the reservoir, i.e. reduced scheme of naphthydogenesis, excluding the process of migration were presented. At the same time, these examples do not exclude the migration of organic matter from the «oil source strata», but are an exception that confirms the general rule. It was shown that the study of organic matter, organic carbon (TOC), chloroform-soluble bitumen, pyrolysis “Rock-Eval”, etc., necessarily supporting the conclusions with data from a detailed study of the hydrocarbon composition at the molecular level.

This article presents the results of studies of the material constitution and physical properties of rocks of foundation of the West Siberian Plate. It is shown that anthraxolite and kerite groups are present in bitumen rocks. We assume that the bitumens create a Late Paleozoic paleo-deposit, transformed under the conditions of apocatagenesis. Impregnation with highly transformed organic matter leads to a significant decrease in electrical resistivity to values of 1–30 Ohm metre, which must be taken into consideration when interpreting low-resistivity zones on log data.

Modern corporation is the main form of social production but its activity and development still remain a largely underex-plored question. Economic theory predominantly relies on simplified approaches based on mathematical modeling to study cor-porations, which gives us little in-depth understanding of the essence of this phenomenon. On the other hand, applied research on corporations does not rise to the level of theoretically significant generalizations. This paper proposes the following theoretical and methodological approach to analyzing the phenomenon of corporation: we identify institutional elements in its structure — institutions and routines. We use the cases of the largest Russian companies to demonstrate the possibility of using this approach to analyze specific corporations and their aggregates. The paper describes nine different routines that structure corporate actors’ interactions based on social norms, coercion, and private interest. We also conduct an analysis of the official sites of Russian cor-porations and sites with employee feedback, which leads us to evaluating each institution’s development from the triad: coercion, assistance, and opportunism. We found a significant correlation between the development level of each corporation’s institutional structure and its efficiency (profitability of sales and capitalization growth rate).

The presented study examines the major problems in the Russian fashion industry and directions of its development according to the Strategy for the Development of the Light Industry of the Russian Federation until 2025; provides examples of innovative materials and technologies; analyzes the issues of environmental friendliness of textile and clothing manufacturers. Aim . The study aims to substantiate promising directions and trends in the fashion industry with allowance for the specific features of the Russian market. Tasks . The authors characterize the fashion industry as a sector of the modern economy; describe trends in the development of the fashion market in the cultural and historical context; identify current trends in the fashion market; describe the existing innovative solutions in the fashion industry. Methods . This study uses the methods of information analysis and synthesis of new knowledge to describe modern innovative solutions in the fashion industry, implementation mechanisms and advantages of cluster policy. Results . The fashion industry exists in the context of severe competition, economic instability, technological and social changes. This determines the key role of branding, economic efficiency, and compliance with environmental standards in gaining competitive advantages. Conclusions . In the post-quarantine period resulting from the removal of restrictions aimed at preventing the spread of COVID-19, successful operation of fashion industry enterprises would require adherence to the principles of economic efficiency and environmental safety of products, new managerial and technological solutions, and state support for the light industry.

Fibromuscular dysplasia (FMD) is a rare disease that affects small and medium-sized arteries. Clinical manifestations of FMD depend on its localization. In many cases, FMD of renal arteries (RA) is associated with arterial hypertension. Young age, particularly of female patients, suspected RA dissection or kidney infarction, absence of atherosclerosis or presence of FMD in other arteries of such patients evidence for RA FMD. In invasive treatment of hemodynamically significant stenoses, transluminal balloon angioplasty (TBA) of renal arteries is preferrable. Taking into account initial alterations of the vascular wall and unevenness of the lumen of the affected blood vessel, stent implantation is associated with an increased risk of complications and is recommended only if ballooning complications develop. An open reconstructive surgery is indicated in complicated narrowing anatomy, a high risk of the endovascular treatment, or after failure of the endovascular intervention. This article presents a clinical case of a young female patient with RA FMD and renovascular arterial hypertension who successfully underwent renal TBA with a drug-coated balloon.

В статье исследовано влияние современных методов маркетинга и менеджмента качества на обеспечение высокого уровня качества и безопасности продукции, определена роль маркетинговых исследований на стадии разработки продукта и научно-технического прогноза в контексте реализации политики импортозамещения.

The data of a comparative enzyme-linked immunosorbent assay of the content of the soluble form of the immunity checkpoint VISTA in the blood serum of 30 healthy donors (control group), 79 patients with primary malignant (osteosarcoma - 30, chondrosarcoma - 31, chordoma - 14) and 14 borderline (giant cell tumor) bone neoplasms are presented. In the general group of patients with malignant neoplasms of bones, the median sVISTA content in blood serum is statistically significant lower than in the control (p = 0.040). In patients with bone tumors and healthy donors over 18 years of age, there was a decrease with age in serum sVISTA levels. There were no significant differences in sVISTA concentration between patients with osteosarcoma, chondrosarcoma and healthy donors. Only in patients with chordoma were sVISTA levels statistically significant lower than in controls (p = 0.013). In the groups of patients with chondrosarcoma and osteosarcoma of the bone, there were no significant associations between the serum sVISTA content and the main clinical and morphological characteristics of the disease. In patients with osteosarcoma, no relationship was found between sVISTA levels and overall survival rates, while in patients with bone chondrosarcoma, there was a tendency towards a favorable prognosis with a high content of the marker in the blood serum.

A criterion for estimating the homogeneity of materials for refractive X-ray optics from small-angle X-ray scattering data is proposed. A material of new type—nanoberyllium—is considered. A number of samples of beryllium materials, including commercial products, have been analyzed. The X-ray homogeneity of the materials is determined, as well as the influence of technological processes.

Geochemical studies of organic matter in source rocks play an important role in predicting the oil and gas accumulation of any territory, especially in oil and gas shale. For deep understanding, pyrolytic analyses are often carried out on samples before and after extraction of hydrocarbon with chloroform. However, extraction is a laborious and time-consuming process and the workload of laboratory equipment and time doubles. In this work, machine learning regression algorithms is applied for forecasting S2ex based on the pyrolytic analytic result of non-extracted samples. This study is carried out using more than 300 samples from 3 different wells in Bazhenov formation, Western Siberia. For developing a prediction model, 5 different machine learning regression algorithms including Multiple Linear Regression, Polynomial Regression, Support vector regression, Decision tree and Random forest have been tested and compared. The performance of these algorithms is examined by R-squared coefficient. The data of the X2 well was used for building a model. Simultaneously, this data is divided into 2 parts – 80% for training and 20% for checking. The model also was used for prediction of wells X1 and X3. Then, these predictive results were compared with the real results, which had been obtained from standard experiments. Despite limited amount of data, the result exceeded all expectations. The result of prediction also showcases that the relationship between before and after extraction parameters are complex and non-linear. The proof is R2 value of Multiple Linear Regression and Polynomial Regression is negative, which means the model is broken. However, Random forest and Decision tree give us a good performance. With the same algorithms, we can apply for prediction all geochemical parameters by depth or utilize them for well-logging data.

Based on a global spatial mathematical model of the global carbon cycle in the biosphere, the change in environmental parameters caused by carbon dioxide emissions from fossil fuel combustion, deforestation, and erosion in African countries are calculated. The impact of deforestation and soil erosion due to inappropriate land use on climate change for African countries is calculated up to 2060.

Microbiota of the deep caves has been poorly explored. The most relevant issues of the caves biodiversity are the sources of the microorganisms’ propagules and characteristics of autochthonous microbiota. The investigation presents the assessment of microbiota biodiversity from the Dzou cave (Western Caucasus). The aim of the study was to identify the species composition of micromycetes and phototrophs of the cave and to assess the sanitary-indicative microbiota in different habitats depending on the anthropogenic load. Microscopic and cultural methods were used to identify the microbiota from the entrance zone of the cave, as well as from aquatic and terrestrial habitats of the unlit deepest parts of the cave. The analysis of the phototrophic communities composition developed in the entrance area of the cave was carried out, 22 species were identified, among which cyanobacteria prevailed. The biodiversity of micromycetes was determined: 48 species were identified in the entrance zone, 60 species – in the dark zone of the cave. Comparison of the species composition of the dark and illuminated zones of the cave showed that in addition to species Humicola grisea, Hemicarpenteles ornatus and Alternaria sp., all species of entrance area are found in the unlit part of the cave. Representatives of genus Penicillium and Aspergillus were dominants. Revealed increase of the micromycetes and bacteria number was driving by increase in the level of anthropogenic load, especially in places of tourist camps. It was noted that the propagules of phototrophs are present in the cave substrates even at great depth, excluding some water samples, which may indicate the periodic drift of propagules or anthropogenic factor. The largest number of micromycetes species was detected in the clay deposits and rock samples. The least number of species was isolated from the water streams of the cave. A large number of micromycetes propagules was found in substrates near tourist camps, but their biodiversity was lower than in cave soils.

Aim. To improve immediate and remote results of reconstructive restorative procedures in patients with complicated colorectal cancer. Methods. The study is based on clinical experience of treatment of 107 patients who had reconstructive restorative procedures performed in specialized oncology institution after previous Hartmanns procedure performed in urgent surgical department for complicated colorectal cancer. Reconstructive restorative procedures were performed at different time after the primary operation. To assess functional state of anal sphincter all patients were adminestered sphincteromentry during the preoperative period. Morphological analysis of all tissues removed during the surgery was performed. To evaluate morphological changes of distal end of the stump at different time a histological analysis was performed. Results. According to the results of sphincterometry dynamic reduction of tonic contraction and maximum pressure of anal sphincter is observed. The more the period between Hartmanns operation and reconstructive restorative surgery, the less pronounced muscle tone of anal sphincter. Histological studies of intestinal wall during the first 3 months after Hartmanns surgery revealed intact quantity and size of intestinal crypts, non-significant inflammatory infiltration of mucous and submucous layers, during the period of 4 to 6 months - initial signs of diversion colitis, during the period of 7 to 12 months - atrophic changes in mucous membrane (reduction of crypts quantity, their shortening, decreased thickness of mucus), after 1 year - signs of atrophy of its submucous layer. Conclusion. Reconstructive surgery in patients with previous Hartmanns surgery for complicated colorectal cancer should be performed in specialized departments with all modern methods of surgical, radiation and medical treatment of colon cancer available; based on functional and morphological studies the optimal time frame for reconstructive surgery is 1 to 3 months after the initial surgery.

The choice of beryllium-based material for the use in X-ray optics has been substantiated based on electron microscopy and X-ray diffraction data. The first results of applying refraction lenses made of this material are reported.

Multiliposome biodegradable conjugates have been obtained via electrostatic binding of a liposome-polylysine complex with micelles formed from a polylactide-poly(ethylene glycol) di- or triblock copolymer. It has been shown that the integrity of liposomes in conjugates is retained. Of special interest is a conjugate based on a polylactide-poly(ethylene glycol) diblock copolymer that exhibits stability in a physiological solution with 0.15 mol/L NaCl, but degrades in the presence of proteolytic enzymes. This fact allows the suggestion that the conjugate will be eliminated from the body after its transport function is completed. The results may be used to create biodegradable liposome containers for drug encapsulation and delivery.

The paper deals with life cycle management of a 3-D printer technology to design an underwater drone hull to study the Arctic. The Arctic region is of strategic importance for the Russian Federation and the entire world community. Due to harsh climatic conditions the scientists started to search for more efficient ways of not only using resources of the territory but also retaining sustainable development of the region. The paper presents a graph that includes activities involved in a 3-D printer life cycle design. A 3-D printer is used for a layer growth of an underwater drone’s hull. The authors took into consideration all the existing options of development, operation and disposal of a particular 3D printer and identified eight variants of its life cycle design based on various financial resources and timing budgets. The study helped to identify a number of effective options. Information and mathematical systems support the implementation of the life cycle management of technology. We selected the following mathematical tools: mathematical programming methods, mathematical statistics, process simulation tools, routine problems, queuing theories. The paper focuses on such information management tools as systems programs, development programs and application software.

The article considers the use of additive technologies in the Arctic region as a tool that contributes to the sustainable development of the Arctic territories. The Arctic region is rich in deposits of minerals, hydrocarbons and other strategically important resources for the Russian Federation. In the article described the current use of additive technologies and a classification of additive technologies according to the following criteria: method of layer formation, method of the powder conversion and on the materials being processed. The types of additive technologies for each classification criterion are considered. A conceptual approach of analyzing the capabilities of additive technologies in the Arctic is proposed, it is based on the classification of the Russian Arctic area into subspaces and consideration of the capabilities of additive technologies for each subspace. Due to the fact that human activity in the Arctic is heterogeneous, the entire region can be divided into subspaces for functional purposes. The article presents the results of the analysis of the possibility of using additive technologies in the following Arctic subspaces: base cities, mobile rotational camps, mineral resource extraction territories, recreational territories, fishing territories, the Northern sea route, and infrastructure for the protection of safe existence. The article describes the application of additive technologies taking into account the functional features of each subspace of the region, describes advantages and limitations of using this technology of its use.

The preparation of high quality seed material requires cleaning on special seed graders. Seeds of different cultures have particular surface and shape. Taking into account these differences, various plants have been developed and are widely used. The need for magnetic cleaning is caused by the impossibility of high-quality separation of seeds of different forestry crops. The analysis of modern technical means for the preparation of seed material showed that the idea of combining air and magnetic cleaning deserves special attention. In air magnetic separation, various forces influence a seed particle, the magnitudes and direction of which vary depending on the design parameters of the inductor and the position of a particle in the magnetic field of an inductor. It is possible to investigate the movement of a particle in the working channel, as well as to create a mathematical model by accepting some assumptions, the result of which will determine the main regularities of the air magnetic separation process and theoretically study the influence of the structural and technological parameters of the air separator on separation process. The particle motion curves were constructed for various values of magnetic force in the working channel according to the results of the analysis of seed motion trajectories. During the course of the research the graph illustrating the possibility of performing the process of air magnetic separation depending on the ratio of the air flow rate and magnetic force influencing a particle is presented.

The small-angle X-ray scattering (SAXS) technique allows to determine size distributions of inhomogeneities in materials and to predict their properties in X-ray optics devices. A number of beryllium materials for the manufacturing of X-ray optics (refractive lenses and speckle suppressors) have been studied by the SAXS. Various composite materials based on porous beryllium have been studied. The effect of adding detonation nanodiamonds to the beryllium matrix on the scattering ability of the material is discussed. Keywords: porous beryllium, SAXS, detonation nanodiamonds, speckle-suppressor

Beryllium materials are widely used in science and technology. They are of importance both for nuclear and thermonuclear energy applications. Additionally, metallic beryllium is transparent to x-ray radiation and used in the manufacture of X-ray windows and refractive x-ray lenses. SC “VNIINM” has developed beryllium materials for various purposes: for coating of the ITER’s first wall, for focusing and controlling X-ray radiation. Porous beryllium is of particular interest as it is an upcoming trend as a temper and neutron multiplier in blankets of thermonuclear facilities. A unique combination of X-ray optical properties also makes it possible to use porous beryllium in imaging devices in a synchrotron radiation beam (speckle suppressor). Key words : beryllium composite, porosity, beryllium-foam, ITER, X-ray optics