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Mechanical processing of hole edges in large-size hull structures of single and double curvature for welding saturation parts into them is an urgent task of shipbuilding. A considerable amount of such machining has to be performed directly on the slipway on a fully assembled structure. To perform such works non-stationary technological machining complexes are used, which have reduced rigidity in comparison with stationary equipment. The article summarizes the results of mathematical modeling of cutting forces during face milling of a workpiece made of high-strength high-viscosity shipbuilding steel. The application of high-speed face milling in order to reduce the value and non-uniformity of cutting forces is theoretically substantiated. Recommendations for selection of technological cutting modes and tool geometry are determined. The obtained experimental data confirm the possibility and expediency of high-speed face milling of hull structures made of hard-to-machine materials under conditions of a low-rigid technological system.

Abstract This paper presents the results of the development of stabilization measures aimed at the removal of zinc with the products of melting and accumulation of titanium in the hearth of a blast furnace. The relevance of the development and use in practice of such measures is due to the unstable fuel and raw materials conditions for the production of cast iron, when their stabilization is a complex and difficult task, as well as the need to extend the campaign of blast furnaces during the overhaul period. The negative effect of zinc oxides on the condition of the blast furnace shaft lining, accompanied by slab formation, and the overconsumption of specific coke consumption, which occurs when zinc circulates in the volume of the blast furnace, require measures to remove zinc from the smelting products. The article proposes such measures, which consist of flushing according to the proposed schedule during the operation of the blast furnace at planned blowing parameters and with the provision of the necessary thermal reserve. In order to lengthen the campaign of a blast furnace, one of the most common methods for protecting the hearth lining is the periodic introduction of titanium‐containing materials into the charge of blast furnaces. The entry of titanium oxides into the furnace, as a rule, is ensured by the use of concentrate or specially prepared ilmenite briquettes with a high titanium content as part of the sinter charge, which can be introduced directly into the composition of the blast furnace charge. The article analyzes the experience of using titanium‐containing materials as part of a blast furnace charge and formulates measures to intensify skull formation in the hearth.

Marine mammals are integral to global biodiversity and marine health through their roles in coastal, benthic, and pelagic ecosystems. Marine mammals face escalating threats from climate change, pollution, and human activities, which perturb their oceanic environment. The diverse biology and extreme adaptations evolved by marine mammals make them important study subjects for understanding anthropogenic pressures on marine ecosystems. However, ethical and logistical constraints restrict the tractability of experimental research with live marine mammals. Additionally, studies on the effects of changing ocean environments are further complicated by intricate gene-environment interactions across populations and species. These obstacles can be overcome with a comprehensive strategy that involves a systems-level approach integrating genotype to phenotype using rigorously defined experimental conditions in vitro and ex vivo. A thorough analysis of the interactions between the genetics of marine mammals and their exposure to anthropogenic pressures will enable robust predictions about how global environmental changes will affect their health and populations. In this perspective, we discuss four challenges of implementing such non-invasive approaches across scientific fields and international borders: 1) practical and ethical limitations of in vivo experimentation with marine mammals, 2) accessibility to relevant tissue samples and cell cultures; 3) open access to harmonized methods and datasets and 4) ethical and equitable research practices. Successful implementation of the proposed approach has the potential impact to inspire new solutions and strategies for marine conservation.

Objectives: Hepatitis C virus (HCV) disproportionately affects people who inject drugs (PWID) worldwide. Despite carrying a high HCV burden, little is known about transmission dynamics in low- and middle-income countries. Methods: We recruited PWID from Nairobi and coastal cities of Mombasa, Kilifi, and Malindi in Kenya at needle and syringe programs. Next-generation sequencing data from HCV hypervariable region 1 were analyzed using Global Hepatitis Outbreak and Surveillance Technology to identify transmission clusters. Results: HCV strains belonged to genotype 1a (n = 64, 46.0%) and 4a (n = 72, 51.8%) and were mixed HCV/1a/4a (n = 3, 2.2%). HCV/1a was dominant (61.2%) in Nairobi, whereas HCV/4a was dominant in Malindi (85.7%) and Kilifi (60.9%), and both genotypes were evenly identified in Mombasa (45.3% for HCV/1a and 50.9% for HCV/4a). Global Hepatitis Outbreak and Surveillance Technology identified 11 transmission clusters involving 90 cases. Strains in the two largest clusters (n = 38 predominantly HCV/4a and n = 32 HCV/1a) were sampled from all four cities. Conclusions: Transmission clusters involving 64.7% of cases indicate an effective sampling of major HCV strains circulating among PWID. Large clusters involving 77.8% of strains from Nairobi and Coast suggest successful introduction of two ancestral HCV/1a and HCV/4a strains to PWID, with widely spread progeny. The disruption of the country-wide transmission network is essential for HCV elimination.

For the first time, a study was conducted to determine the effectiveness of the use of Hericium erinaceus BP 16 polysaccharides mixed with AndroMed® to preserve the motility of bull spermatozoa after freezing and storage at -5 °C. H. erinaceus polysaccharides have been shown to increase the osmolarity of AndroMed® solution, which lowers its freezing point. It has been established that the motility of progressive spermatozoa after 7 days of storage at - 5°C is preserved to the greatest extent in the presence of H. erinaceus polysaccharides in the biological medium. At the same time, in the group with polysaccharides, there was a decrease in such indicators of mobility as the speed along the average trajectory, wobble, and beat frequency. The data obtained indicate the promise of using H. erinaceus polysaccharides as part of a cryoprotective solution to preserve the functional usefulness of gametes during their freezing.

Rates of fast reactions are inversely proportional to the solvent viscosity (η). However, a quantitative study demonstrates that dynamic viscosity η is often a crude reflection of a viscous drug exerted on a molecule or radical. This paper aims to present an accurate dependence of the rates of fast bi- and monomolecular reactions upon the viscous drug of a media. Different correction coefficients fmicro are discussed, which should lead to a dependence rate ∝ (fmicroη)−1. Microviscosity is viscosity, leading to the expected rate dependence upon shear viscosity. In many cases, experimentally measured diffusion coefficients of molecules of a similar structure to the reactive radicals lead to the correct prediction of radicals’ diffusion coefficients and the rate constants of radicals recombination. Microviscosity of complex non-Newtonian liquids (biological liquids, polymeric solutions) can be measured using low MW molecular probes. Usually, the measured ηmicro is much lower than the shear η of complex biological or polymeric liquids. Cis–trans isomerization of bulky groups in monomolecular reactions is often described with Kramers’ theory. An example of such isomerization of a cyanine dye studied experimentally and theoretically is presented. It is demonstrated in the selected case that Kramers’ theory adequately describes the dependence of cis–trans isomerization of organic compounds upon η.

Abstract The $$K^{+} \rightarrow \pi ^{+}\pi ^{0}\pi ^{0}\gamma $$ K + → π + π 0 π 0 γ decay is observed by the OKA collaboration. About 60 events of the decay observed with signal:noise $$\approx 1$$ ≈ 1 . The branching ratio obtained by normalization to $$K^{+} \rightarrow \pi ^{+}\pi ^{0}\pi ^{0}$$ K + → π + π 0 π 0 is measured to be $$(3.7 \pm 0.9(stat) \pm 0.3(syst))\times 10^{-6}$$ ( 3.7 ± 0.9 ( s t a t ) ± 0.3 ( s y s t ) ) × 10 - 6 for $$E_{\gamma }^*>10\,\textrm{MeV}$$ E γ ∗ > 10 MeV . The branching ratio, $$\gamma $$ γ energy spectrum and angular distribution are consistent with ChPT prediction.

Abstract A high-statistics data sample of the $$K^{+}$$ K + decays is recorded by the OKA collaboration. A missing mass analysis is performed to search for a light invisible pseudoscalar axion-like particle (ALP) a in the decay $$K^{+} \rightarrow \pi ^{+} \pi ^{0} a$$ K + → π + π 0 a . No signal is observed, and the upper limits for the branching ratio of the decay are calculated. The $$90\%$$ 90 % confidence level upper limit changes from $$2.5\cdot 10^{-6}$$ 2.5 · 10 - 6 to $$2\cdot 10^{-7}$$ 2 · 10 - 7 for the ALP mass from 0 to 200 MeV/ $$c^{2}$$ c 2 , except for the region of $$\pi ^{0}$$ π 0 mass, where the upper limit is $$4.4\cdot 10^{-6}$$ 4.4 · 10 - 6 .

Mechanical processing of hole edges in large-size hull structures of single and double curvature for welding saturation parts into them is an urgent task of shipbuilding. A considerable amount of such machining has to be performed directly on the slipway on a fully assembled structure. To perform such works non-stationary technological machining complexes are used, which have reduced rigidity in comparison with stationary equipment. The article summarizes the results of mathematical modeling of cutting forces during face milling of a workpiece made of high-strength high-viscosity shipbuilding steel. The application of high-speed face milling in order to reduce the value and non-uniformity of cutting forces is theoretically substantiated. Recommendations for selection of technological cutting modes and tool geometry are determined. The obtained experimental data confirm the possibility and expediency of high-speed face milling of hull structures made of hard-to-machine materials under conditions of a low-rigid technological system.

Purpose. Demonstration of non-standard clinical case of removing large fragment of metal wire from the eye. Patient and methods. Patient, 37 years old, with penetrating right eye injury with intraocular foreign body (IOFB) introduction — a fragment of metal wire. After unsuccessful attempt to remove IOFB during primary repair of eye injuries lacerations by ophthalmologist of the surgical department of the district hospital, he was sent to the Khabarovsk branch of the S. Fyodorov Eye Microsurgery Federal State Institution. On admission: VIS OD — 0.01 uncorrected, intraocular pressure (IOP) — 16 mm Hg (noncontact tonometer TOMEY, Japan). OD — metal IOFB protrudes by 1.0 mm from the corneoscleral laceration in projection of corneal limbus at the 13 o’clock position, postoperative aphakia; according to B-scan ultrasonic data: metallic foreign body of linear shape, 14.3 mm long, about 1.5 mm thick. There is hemorrhage in the vitreous cavity. Results. Initially, conditions for visualization of the vitreous cavity were created by performing 25G vitrectomy. The course of wire location was specified: under the choroid and retina, going out through the sclera in the equatorial region. After conjunctival tweezers expanded wound edges, the embedded fragment of wire was delicately remove: 25 mm in length and 2 mm in diameter. A single retinal break was delimited by cryotherapy and laser photocoagulation. On the 2nd day: VIS OD — 0.3 with diaphragm, uncorrected; IOP — 13 mm Hg. After 3 months: VIS OD — 0.01 sph + 13.0 D = 0.7, IOP — 14 mm Hg. Silicone removal was combined with intraocular lens implantation model RSP-3 (+23D). The next day: VIS OD — 0.3 with diaphragm, 0.5 cyl — 6.0 D ax 170 = 0.5; IOP — 16 mm Hg. Conclusion. Use of 25G vitrectomy for removal IOFB localized between the inner membranes of the eye created optimal conditions for visualizing depth of its penetration, which minimized traumatic impact and avoided severe intra- and postoperative complications.

Blubber is a modified subcutaneous adipose tissue in marine mammals that provides energy storage, thermoregulation, hydrodynamic locomotion, and buoyancy. Blubber displays vertical stratification by lipid content, fatty acid composition, and vascularization, leading to the assumption that deeper blubber layers are metabolically active, while superficial layers are mainly structural and thermoregulatory. However, few studies have examined functional stratification of marine mammal blubber directly, especially in pinnipeds. We characterized morphological and transcriptional differences across blubber layers in the northern elephant seal, a deep-diving and fasting-adapted phocid. We collected blubber from seals early in their fasting period and divided blubber cores into three similarly sized portions. We hypothesized that the innermost blubber portion would have higher 1) heterogeneity in adipocyte size, 2) microvascular density, and 3) expression of genes associated with metabolism and hormone signaling than outer blubber. We found that adipocyte area and variance increased from outermost (skin-adjacent) to innermost (muscle-adjacent) blubber layers, suggesting that inner blubber has a higher capacity for lipid storage and turnover than outer blubber. Inner blubber had a higher proportion of CD144+ endothelial cells, suggesting higher microvascular density. In contrast, outer blubber had a higher proportion of CD4+ immune cells than inner blubber, suggesting higher capacity for response to tissue injury. Transcriptome analysis identified 61 genes that were differentially expressed between inner and outer blubber layers, many of which have not been studied previously in marine mammals. Based on known functions of these genes in other mammals, we suggest that inner blubber has potentially higher 1) adipogenic capacity, 2) cellular diversity, and 3) metabolic and neuroendocrine signaling activity, while outer blubber may have higher 1) extracellular matrix synthesis activity and 2) responsiveness to pathogens and cell stressors. We further characterized expression of nine genes of interest identified by transcriptomics and two adipokines with higher precision across blubber layers using targeted assays. Our study provides functional insights into stratification of blubber in marine mammals and a molecular key, including CD144, CD4, HMGCS2, GABRG2, HCAR2, and COL1A2, for distinguishing blubber layers for physiological and functional studies in seals.

The ability to respond rapidly to changes in oxygen tension is critical for many forms of life. Challenges to oxygen homeostasis, specifically in the contexts of evolutionary biology and biomedicine, provide important insights into mechanisms of hypoxia adaptation and tolerance. Here we synthesize findings across varying time domains of hypoxia in terms of oxygen delivery, ranging from early animal to modern human evolution and examine the potential impacts of environmental and clinical challenges through emerging multi-omics approaches. We discuss how diverse animal species have adapted to hypoxic environments, how humans vary in their responses to hypoxia (i.e., in the context of high-altitude exposure, cardiopulmonary disease, and sleep apnea), and how findings from each of these fields inform the other and lead to promising new directions in basic and clinical hypoxia research.

Formation of the excited doublet (D) and quartet (Q) states of free radicals under their photoexcitation is discussed. The relative positions of the D and Q states are compared to the positions of the photoexcited states of organic molecules (Jablonsky diagram). A number of representative cases of the excited states of free radicals detected by their transient absorption or emission are presented. A special case of the population having the lowest Q state in some radicals is discussed. A spin–statistical factor in the reactions of Q and D is debated.

Способность стероидных гормонов модулировать связывание окситоцина с окситоциновыми рецепторами представляет большой интерес. Цель работы – изучить влияние окситоцина, дидрогестерона и их смеси на радикальную активность нейтрофилов венозной крови женщин в III триместре физиологически протекающей беременности и женщин в первые сутки после завершения срочных родов. Материалы и методы. С помощью хемилюминесцентного метода (аппарат БХЛ-07) изучено негеномное и геномное влияние дидрогестерона (5∙10–5 г/л), окситоцина (10–7 МЕ/л) и их смеси на радикальную активность нейтрофилов венозной крови 20 женщин в III триместре физиологически протекающей беременности и 10 женщин в первые сутки после завершения срочных родов при стимуляции клеток латексными частицами. При автоматическом вычете уровня шума регистрировали: максимальное значение интенсивности синтеза активных форм кислорода, время выхода интенсивности процесса на максимум, а также площадь под кривой хемилюминограммы, отражающую суммарный синтез радикальных частиц за 30 мин (время исследования). Результаты. Установлено, что фоновая радикальная активность нейтрофилов у женщин в первые сутки после завершения срочных родов была в 3 раза выше, чем у женщин в III триместре физиологически протекающей беременности. Согласно площади под кривой хемилюминограммы и максимальному значению интенсивности синтеза активных форм кислорода, окситоцин оказывал стимулирующий эффект на нейтрофилы венозной крови как беременных женщин в III триместре, так и родильниц (в равной степени). Дидрогестерон в каждой группе женщин в равной степени негеномно и геномно стимулировал радикальную активность нейтрофилов. Окситоцинореактивность нейтрофилов крови у женщин каждой группы при действии дидрогестерона через мембранные рецепторы не менялась, через ядерные – снижалась. Рассмотрены возможные механизмы участия прогестерона в регуляции окситоцинореактивности миометрия и нейтрофилов венозной крови женщин при беременности и после ее завершения.

Marine mammals such as northern elephant seals (NES) routinely experience hypoxemia and ischemia-reperfusion events to many tissues during deep dives with no apparent adverse effects. Adaptations to diving include increased antioxidants and elevated oxygen storage capacity associated with high hemoprotein content in blood and muscle. The natural turnover of heme by heme oxygenase enzymes (encoded by HMOX1 and HMOX2) produces endogenous carbon monoxide (CO), which is present at high levels in NES blood and has been shown to have cytoprotective effects in laboratory systems exposed to hypoxia. To understand how pathways associated with endogenous CO production and signaling change across ontogeny in diving mammals, we measured muscle CO and baseline expression of 17 CO-related genes in skeletal muscle and whole blood of three age classes of NES. Muscle CO levels approached those of animals exposed to high exogenous CO, increased with age, and were significantly correlated with gene expression levels. Muscle expression of genes associated with CO production and antioxidant defenses (HMOX1, BVR, GPX3, PRDX1) increased with age and was highest in adult females, while that of genes associated with protection from lipid peroxidation (GPX4, PRDX6, PRDX1, SIRT1) was highest in adult males. In contrast, muscle expression of mitochondrial biogenesis regulators (PGC1A, ESRRA, ESRRG) was highest in pups, while genes associated with inflammation (HMOX2, NRF2, IL1B) did not vary with age or sex. Blood expression of genes involved in regulation of inflammation (IL1B, NRF2, BVR, IL10) was highest in pups, while HMOX1, HMOX2 and pro-inflammatory markers (TLR4, CCL4, PRDX1, TNFA) did not vary with age. We propose that ontogenetic upregulation of baseline HMOX1 expression in skeletal muscle of NES may, in part, underlie increases in CO levels and expression of genes encoding antioxidant enzymes. HMOX2, in turn, may play a role in regulating inflammation related to ischemia and reperfusion in muscle and circulating immune cells. Our data suggest putative ontogenetic mechanisms that may enable phocid pups to transition to a deep-diving lifestyle, including high baseline expression of genes associated with mitochondrial biogenesis and immune system activation during postnatal development and increased expression of genes associated with protection from lipid peroxidation in adulthood.

Aim. To analyze availability and affordability of alcoholic beverages in Russian cities.Material and methods. We assessed the actual state of urban infrastructure in the Arkhangelsk, Tver and Sverdlovsk regions. Data were collected in three districts of Arkhangelsk, three districts of Tver, three districts of Yekaterinburg and Revda, where participants of the Epidemiology of Cardiovascular Diseases and their Risk Factors in Regions of Russian Federation-3 (ESSE-RF3) study (2021) lived. The study objects were elements of the city infrastructure where alcoholic beverages were sold. To assess the infrastructure, special software was developed to collect and analyze the necessary data using Open Street Maps. Data were collected from January to March 2022.Results. In total, 1180 alcohol-selling outlets were identified in the study areas: in Arkhangelsk — 450, in Yekaterinburg and Revda — 444, and in Tver — 286. Mainly alcoholic beverages in Sverdlovsk and Tver regions can be purchased in the alcohol section of a grocery store (n=260, 58,6% and n=185, 41,4%, respectively), and in the Arkhangelsk region — in a specialized liquor stores (n=263, 58,4%). The median number of alcohol stores located within a radius of 1000 m from the place of residence of the ESSE-RF3 participant was 33, and within a radius of 400 meters — 8. In Arkhangelsk, the alcohol was sold in a grocery store located in the same building as the college branch. In the Sverdlovsk region, the nearest alcohol store was located at a distance of 50 m from the kindergarten, in the Tver region — 44 m from the college. A 0,5 liter bottle of vodka was sold below the price floor in 55,1% of specialized liquor stores in the Sverdlovsk region and in 66,8% of such liquor stores in the Tver region.Conclusion. As a result of the study, availability and affordability of alcoholic beverages in Arkhangelsk, Tver, Yekaterinburg and Revda was assessed. The findings reflect the high availability of alcohol and indicate the need for interventions at both the national and local government levels. The used method of collecting and analyzing data demonstrated sufficient research effectiveness and can be recommended for wider use.

Aim. To study the relationship of the density and proximity of tobacco products (TPs) and electronic nicotine delivery systems (ENDS) with increased levels of depression, anxiety and stress among the population in 3 constituent entities of the Russian Federation.Material and methods. The work used data from the Epidemiology of Cardiovascular Diseases and their Risk Factors in Regions of Russian Federation-3 (ESSE-RF3) study in 3 Russian regions (Arkhangelsk, Sverdlovsk and Tver regions) among the population aged 35-64 years (n=1674), who signed a consent to participate in the study. We analyzed data on the status of smoking and consumption of ENDS, passive smoking, attempts to quit smoking, as well as the presence of depression, anxiety (Hospital Anxiety and Depression Scale (HADS) score ≥8) and stress (Perceived Stress Scale (PSS) >21). Elements of urban infrastructure (data collection: January-March 2022) selling TPs and ENDS were assessed using aт OpenStreetMap-based program. Associations were established using logistic regression analysis.Results. With a twofold increase in the distance of TP and ENDS outlets from the place of residence, the depression probability was reduced by 13% (odds ratio (OR) 0,87; 95% confidence interval (CI): 0,79-0,96) and by 12% (OR 0,88; 95% CI: 0,78-0,99), respectively. With increase in distance from of TP outlets, the anxiety decreased probability by 12% (OR 0,88; 95% CI: 0,81-0,97). With an increase in the number of TP outlets within a radius of 1000 m from the place of residence, there were an increase in the probability of depression (OR 1,18; 95% CI: 1,031,36), anxiety (OR 1,12; 95% CI: 1-1,26) and stress (OR 1,24; 95% CI: 1,05-1,46). A greater number of ENDS outlets within a radius of 1000 m and 400 m was associated with a high likelihood of depression (OR 1,17; 95% CI: 1,02-1,34 and OR 1,25; 95% CI: 1,04-1,47, respectively). An increased depression probability was found in those exposed to tobacco smoke at home (OR 1,88; 95% CI: 1,27-2,73) and at work (OR 1,67; 95% CI: 1,14-2,41). An increase in the number of attempts to quit smoking doubles the odds of depression (OR 2,40; 95% CI: 1,35-4,23) and anxiety (OR 2,00; 95% CI: 1,18-3,38).Conclusion. Unfavorable environmental factors, including the proximity and density of TP and ENDS outlets, can increase the probability of depression, anxiety and stress among the population living in these areas.

Marine mammals are exposed to increasing intensities of anthropogenic stressors such as acoustic disturbance and contaminants. Correlative studies have suggested concerning shifts in behavioral and physiological status of stress-exposed individuals, which could alter the health and survival of marine mammal populations. However, functional studies of the effects of multiple stressors on marine mammals are lacking. To fill in this gap, we recently developed an ex vivo approach of precision-cut adipose tissue slices (PCATS) to study the impact of stressors on the function of an essential endocrine organ: the adipose tissue. In the present study, we investigated the impact of hormones associated with the stress response on adipose tissue from northern elephant seals (Mirounga angustirostris). Blubber biopsies were collected from 17 weaned northern elephant seal pups, separated into inner and outer layers, dissected into PCATS, and cultured for 48 hours. To mimic prolonged and short-term exposure to physiological stress, PCATS were treated with 2 µM cortisol (CORT) for the entire 48 hours or 100 nM epinephrine (EPI) for the last 12 hours of culture, respectively. Hormones were applied individually or in combination. CORT and EPI exhibited an interacting, blubber layer-dependent, effect on adipose tissue biology, as quantified by gene expression in PCATS, and release of glycerol, free fatty acids, leptin and polychlorinated biphenyls into culture media. EPI stimulated a higher rate of lipolysis than CORT in PCATS from both blubber layers. The combination of CORT and EPI upregulated the expression of adipose triglyceride lipase in inner blubber PCATS and downregulated hormone-sensitive lipase in outer blubber-derived PCATS. Expression of the leptin gene and secretion of the leptin adipokine were both decreased by EPI, while addition of CORT attenuated this effect in inner blubber PCATS only. CORT also increased the expression of the antioxidant enzyme glutathione peroxidase 3 in PCATS from both blubber layers. Polychlorinated biphenyls exhibited selective and limited mobilization from PCATS treated with stress hormones, highlighting the lipophilic properties of these toxic compounds. This study showed that physiological stress can impact several essential functions of marine mammal blubber, such as lipolysis and adipokine production.