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The data of trap surveys and observations aboard fishing vessels conducted in the northwestern Tatar Strait (northward from Cape Zolotoy) in 2009–2022 are analyzed. Horsehair crabs dwell along the entire continental coast from Cape Zolotoy in the south to Cape Nakatov in the north, but commercial aggregations with the density on average 232 ind./km2 are concentrated in the southern part of this area (south of 49о N). Seasonal bathymetric migrations of the crab include the fall moving of commercial males from the depths of 10–40 m to the depths of 40–60 m for wintering and their return to shallows in spring. Two dense wintering aggregations are formed usually between Cape Peschany – Cape Mapatsa and southward from 48о00′ N, whereas sparse summer aggregations are widely distributed along the coast. Regardless the season, the aggregations density decreases from south to north. The males are generally larger in the southern aggregations than in the northern ones (on average, 100.3 and 89.8 mm of carapace width, respectively), the difference is statistically significant (p < 0.0001). The stock of horsehair crab in the northwestern Tatar Strait has increased in the last 20 years from136 tons in 2003 to 1580 tons in 2022. Over the past 10 years, the optimal allowable catch in the Primorye subzone north of Cape Zolotoy was utilized less than 50 %. There is no specialized fishery of horsehair crab; the species is caught mainly as bycatch for other shelf crab species. High current level of the stock gives a good background for commercial removal of at least 158 t of horsehair crab without damage to the local population of this species.

Introduction. Most modern bullet and high-speed electric trains are equipped with a Class II power actuator with stiff or elastic support of electric motors on the bogie frame. Both tractive motors on the bogies of electric trains of the Velaro platform and on the Sapsan High-Speed Electric Train are rigidly supported on the underpan, which is elastically connected to the bogie frame in the transverse direction by means of four leaf springs. Due to the low lateral stiffness of the suspension, when the train is moving, the underpan with the electric tractive motor makes transverse displacement relative to the bogie frame depending on the amount of free play of the underpan. This design acts as a dynamic shock absorber in a certain frequency range and contributes to an increase in the critical speed of the train.Materials and methods. In order to evaluate the properties of the electric tractive motor transverse cushioning, the bogie frame was subjected to an amplitude-frequency analysis and a study of free and forced horizontal oscillations of the elastic and stiff suspension systems of the electric tractive motor on the bogie frame with the definition of probabilistic characteristics of random processes. For these purposes, a 3D simulation model of a motor car of a high-speed electric train has been developed in the Universal Mechanism software package. Numerical simulations gave realisations of stationary and ergodic random processes.Results. The transverse cushioning of the electric tractive motor gives it the function of a dynamic shock absorber, has a positive impact on the stability of the cab at high speed, significantly reduces the amplitude and frequency of horizontal oscillations of the bogie frame, as well as frame forces. The maximum effect of dynamic damping is achieved at a natural frequency of transverse oscillations of the electric tractive motor, close to the frequency of transverse oscillations of the wheel pair.Discussion and conclusion. The dynamic damping effect can be obtained within a certain range of the natural frequency of transverse oscillations of the electric tractive motor, depending on the parameters of the contact between the wheel and the rail, damping of the horizontal oscillations of the electric motor necessary to limit the resonant oscillation amplitudes. At the same time, the low stiffness of the suspension contributes to an increase in the transverse and angular displacement of the electric tractive motor. Permissible transverse and angular displacement require regulation depending on the characteristics of the gear clutch and the parameters of the undercarriage as a whole at the design stage of this design.

Experiments on comparing the methods for assessment of Saccharina japonica commercial stock were conducted in 2021. In total, 11 sites in the northwestern Tatar Strait southward from the Sovetskaya Gavan Bay, along the 44 km stretch of coastline between Cape Krasny Partizan (48о58′ N 140о23′ E) and Cape Korovin (48о37′ N 140о11′ E), were surveyed aboard RV Ubezhdenny and small boats. This is a traditional area of Saccharina japonica commercial harvesting. Four methods were compared: 1) visual assessment of projective cover from the sea surface by two observers independently; 2) assessment of projective cover by two observers independently on the images obtained from a remotely operated underwater vehicle (ROV); 3) estimation of projective cover by a diver; and 4) assessment on the data of quantitative diving samples. The former three methods are comparable and differ by 1.2–1.7 times. The estimates made by the latter method of diving sampling exceed them by 2.4–4.1 times because of artifacts specific to this method. To eliminate inaccuracies, diving samples should be collected under control from the sea surface by ROV. Evaluation of the projective cover by diver is inadvisable. Visual assessments of the projective cover from the sea surface are simple and cheap but inconvenient for documentation. The stock assessment with micro-ROV is recognized as the optimal method provided an adequate accounting of the kelp abundance and complete documenting of the survey materials.

Background. The article deals with the theory of constraints in relation to the specifics of the functioning of research and production enterprises. The trends in the work of the research and production sphere are analyzed. The purpose of the article is to systematize scientific approaches to the application of the theory of constraints for the work of research and production enterprises, to identify trends in their development and to develop systemic characteristics of the "bottlenecks" in the innovation activity of research and production enterprises. Materials and methods. The information base of the study was the theory of the firm, the theory of organization of industrial production, technological theory, the theory of cluster models, the theory of lean production, and the theory of innovation. Official statistics were used as the statistical base. The time series for comparative assessment was 2017–2022. Description, comparative and comparative analysis, time series analysis, descriptive statistics methods, trend analysis, regression analysis, methods of analysis, synthesis and generalization are used as research methods in the article. Results. The stages of work with "bottlenecks" in the theory of constraints for research and production enterprises are systematized. A classification of limitations ("bottlenecks") of innovative activity of research and production enterprises has been developed. Conclusions. The fundamental difference of the proposed approach lies in the improvement of the methodological foundations for determining and eliminating restrictions of a different nature in the functioning of research and production enterprises.

Modern uranium enrichment facilities can simultaneously use several raw materials as feed, including natural uranium, regenerated uranium obtained as a result of SNF reprocessing, or depleted uranium (all in the form of uranium hexafluoride). As the output of the separating cascade, several types of enriched uranium product with different levels of enrichment can be fabricated simultaneously. The paper proposes a methodology, absent in literature, for calculating the cost of each enriched uranium product in multi-stream separating cascades. The proposed methodology uses standard definitions of the isotopic value of feed and product stream and the Peierls-Dirac separation potential. Numerical calculations of the cost of enriched uranium products for three production problems are provided as examples of the methodology effectiveness: 1) involvement of depleted uranium hexafluoride (DUHF) in fabrication of enriched uranium product; 2) simultaneous fabrication of two enriched products; 3) use of depleted uranium to reduce the cost of the product with a higher enrichment level out of two (as applied, e.g., to advanced tolerant fuel). It has been shown that partial additions of DUHF as feed for a multi-product separating cascade make it possible to reduce the cost of a product with a higher level of enrichment; with the current market prices for natural uranium and separative work, there is a range of tails assays in which it is more profitable to enrich DUHF rather than natural uranium.

The demand for the use of radioactive isotopes in medicine is increasing with each coming year necessitating the increased output of radionuclide products. One of the most widely spread radionuclides used in medicine is technetium-99m (99mТс) (Feasibility of producing molybdenum-99 2015, NEA 2012, The Supply of Medical Radioisotopes 2015). The very short 99mТс life (6-hour half-life) requires its production directly on the site of medical treatment. This is achieved using molybdenum-technetium generators (Kodina and Krasikova 2014, Technical Reports No. NF-T-5.4. 2013, Technetium-99 Generator 2021) loaded with molybdenum-99 (99Мо), which uninterruptedly decays (half-life of 66 hours) yielding 99mTc. Close attention must be paid in the course of production of molybdenum-technetium generators to radiation safety during transportation of 99Мо on the territory of the manufacturing facility. The main measure for ensuring radiation safety during transportation of 99Мо is the application of special packaging kits. The Karpov Institute of Physical Chemistry JSC uses a wide range of packaging kits of types A and B for transportation of radioactive materials on the territory of the manufacturer with design features providing the required level of radiation safety. In particular, the KL-15 shipping cask loaded/unloaded from the top is used for onsite transportation of 99Мо for charging molybdenum-technetium generators. The maximum permissible activity of 99Мо is not specified in the passport of the KL-15 cask. Planned construction of a radionuclide production shop in accordance with GMP requirements will require the increase of output of target radionuclides by several times. The above considerations necessitated the evaluation of the maximum permissible activity of 99Мо planned to be transported in KL-15 casks. No other type of standard casks can be used because of their outside dimensions prohibiting the unloading of 99Мо inside the “hot” chamber. Calculation and experimental evaluation of permissible 99Мо activity during transportation inside the KL-15 cask was performed. The paper presents the calculated evaluation of the maximum permissible activity of 99Мо in a KL-15 cask to ensure the radiation exposure of personnel of group A working with the cask not exceeding the established level at the enterprise (80 μSv per shift) and not requiring the use of additional measures and means of protection. The results of the work allow us drawing the conclusion that the KL-15 cask ensures the required level of radiation safety with up to 241 Ki of 99Мо loaded in the cask.

An economic and analytical model for evaluating the criteria of efficiency (profitability) of investments in the projects of innovative nuclear icebreakers of the Northern Sea Route is suggested. The model is based on the new analytical representation of the methodology for forecasting the investment project efficiency that is widely used in international practice. The mathematical expression for the net discounted income provides convenient formulas for calculating several investment efficiency criteria for nuclear icebreakers: internal rate of return, minimum annual revenues from icebreaker convoys, discounted payback period, and the volume of delivered cargo. The paper gives estimates of the criteria for the efficiency of investments in “Leader” class icebreakers that depend on the discount rate of cash flows, capital, and operating costs. It is shown that at high capital costs, typical for construction of “Leader” class nuclear icebreakers, the minimum required revenue of an icebreaker, representing a financial burden for ships transporting cargo along the NSR, rapidly increases with the growth of discount rate and the reduction of investment payback period. This means that the profitability of such icebreakers is only possible at low discount rates of 2–3% per year, which is an extremely low-interest credit. Even with low interest and impressive technical characteristics of the icebreaker (high speed of navigation, large number of ships in the caravan and their maximum capacity) the payback period would exceed 25 years.

Abstract Aims Insulin‐like growth factor binding protein‐4 (IGFBP‐4) fragments have been shown to predict the risk of major adverse cardiovascular events, including segment‐elevation myocardial infarction, in patients with acute coronary syndrome. We evaluated the prognostic value of the carboxy‐terminal fragment of IGFBP‐4 (CT‐IGFBP‐4) for all‐cause mortality in emergency room patients with acute heart failure (AHF). Methods and results CT‐IGFBP‐4, N‐terminal pro brain natriuretic peptide (NT‐proBNP), and C‐reactive protein (CRP) were measured at admission from the lithium‐heparin plasma of 156 patients with AHF. All‐cause mortality was recorded for 1 year. Receiver operator characteristic (ROC) curves, Kaplan–Meier, and Cox proportional hazard ratio analyses were performed to evaluate the prognostic value of the various clinical variables, CT‐IGFBP‐4, NT‐proBNP, CRP, and their combinations. During 1 year of follow‐up, 52 (33.3%) patients died. CT‐IGFBP‐4 only weakly correlated with NT‐proBNP (Pearson correlation coefficient r = 0.16, P = 0.044) and did not correlate with CRP (r = 0.08, P = 0.35), emphasizing the different nature of these biomarkers. The receiver operator characteristic area under the curve (ROC AUC) of CT‐IGFBP‐4 for the prediction of all‐cause mortality (0.727) was significantly higher than that of NT‐proBNP (0.680, P = 0.045) and CRP (0.669, P = 0.016). The combination of CT‐IGFBP‐4, NT‐proBNP, and CRP predicted mortality significantly better (ROC AUC = 0.788) than any of the biomarkers alone (P

Isospongian diterpenes are a small but growing family of natural tetracyclic secondary metabolites isolated from marine organisms, primarily sponges and nudibranchs. A palladium-catalyzed domino Heck–Suzuki reaction sequence for the synthesis of the tetracyclic skeleton of marginatafuran-type isospongian diterpenoids with a wide variety of substituents in the C-17 position is reported. The proposed approach was based on selective transformations of the accessible plant diterpenoid lambertianic acid and includes an intramolecular Heck reaction of 16-bromolambertianic and arylation of the palladium intermediate with arylboronic acid. The influence of the nature of the substituent both in arylboronic acids and in the furan ring of 16-bromolambertianic acid on the direction and chemoselectivity of the reaction has been studied. The described derivatization of natural furanolabdanoid lambertianic acid produced new functionalized molecules for biological study and gave novel insights into the reactivity of complex molecular structures.

The article presents the results of a study on the application possibilities developed by the authors method of «intrapsychic interview» carried out in the structure of the psychiatric examination of patients with depressive episodes of moderate and mild degree. In the comparison group were healthy individuals, who were also conducting «intrapsychic interview». The study involved 64 patients with an established diagnosis of depressive episode (F31.3, F32.0, F32.1) and 23 healthy mental attitude of a person. The study revealed that patients with depressive symptoms experience mental phenomena is characterized by the tendency to avoid experiencing negative feelings, the desire to achieve a state of «inner peace», a tendency to postpone the satisfaction of natural needs, a decline in the ability to recognize their own feelings and their interpretation. According to the study it is assumed that the «intrapsychic interview» allows you to achieve a more complete understanding of the clinical picture of mental disorders and their dynamics.