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Abstract Chaun Bay, located on the fringe of the East Siberian Sea, has been described since the mid-20th century to support a unique marine ecosystem that is atypical for the local Siberian Arctic. Here we use ship-board physical, biogeochemical and geological measurements taken in October 2020, along with hydrographic observations taken from land-fast ice in April 2023, to demonstrate that these warm-water biological communities are supported by hydrothermal submarine groundwater discharge that delivers heat, salinity, nutrients, and trace elements to the bay. We identify a cyclonic eddy that mixes the warm nutrient-rich groundwater with oxygen-rich surface water, resulting in a water mass within Chaun Bay that has similar physical and chemical properties to the highly productive waters of the North Pacific and Southern Chukchi Sea. The bay showed elevated concentrations of chlorophyll-a and zooplankton, and the abundance and species diversity of epibenthos significantly exceeded values observed elsewhere in the East Siberian Sea. The benthic communities contained a number of boreal species that are not typically found in the Arctic Ocean. We also observed Thysanoessa krill populations, a pelagic species generally considered an expatriate in Arctic waters.

According to 2022 statistics from the Federal State Budgetary Institution National Medical Research Center for Endocrinology, the incidence of type 2 diabetes mellitus in Russia is 92.4% (4.49 million) of patients, and every tenth inhabitant of the Earth already suffers from diabetes mellitus.Purpose of the study: to analyze the dynamics of superoxide dismutase and catalase activity at the systemic and local levels in rats of different ages when modeling type 2 diabetes followed by mechanical injury to skeletal muscle.Object and methods. The study was conducted on white outbred healthy male rats 24 months old (120 individuals) and 6 months old (120 individuals). All old and young animals were divided into four subgroups within their group, 30 animals in each. Animals of the first subgroup in groups of old and young rats are intact rats. Animals of the second subgroup of the group in each group had a mechanical dissection in the area of the middle third of the gastrocnemius muscle of the hind limb. Animals of the third and fourth subgroups of each group were subjected to modeling type 2 diabetes mellitus.After the specified time, the animals of the fourth subgroup of both groups were injured in the middle third of the gastrocnemius muscle of the hind limb.Conclusions. Mechanical injury to the gastrocnemius muscle in combination with type 2 diabetes mellitus is characterized by an intensification of lipid peroxidation and leads to an increase in superoxide dismutase activity in the liver tissue and blood serum of rats, and in young animals the increase in superoxide dismutase activity is more intense than in old ones.

The authors investigate the agenda of the so-called ‘big three’ TV channels and popular online media during the presidential elections 2018 in Russia. In the context of an election campaign, the significance of qualitative public awareness grows exponentially. The given research studies the agenda of those media, the coverage of the election campaign, and also the possible ‘silencing effect’. An unique research design that allowed the content comparison between evening TV news and online media is developed, and also the notion of ‘silencing effect’ is conceptualized. Online media are often considered more qualitative and full-fledged sources of information; nevertheless, the research demonstrates that information concerned the elections was published on the Internet on a smaller scale and irregularly. The study confirmed that television in Russia, first of all, was an assistant to the government, directing its efforts to inform citizens about authorities and their socially significant initiatives. Besides, television covered the presidential elections in a better extent. Online media devoted more attention to scandalous news, attempted to criticize the government; however, they overlooked significant social issues.

Anxiety is a natural survival mechanism that helps to cope with potentially dangerous situations. It is accompanied by changes in the functioning of the nervous and endocrine systems, which affect the behavior of living beings. It is possible to establish the level of anxiety and the severity of depression thanks to various behavioral methods, with the help of which it is possible to fix indicators, establish their duration, and then compare data on the emotional state of animals from the control and experimental groups. The purpose of the study: to identify the features of the emotional state of the offspring of rats that received an aqueous plant extract of reddish hellebore. Conclusions: aquatic plant extract of reddish hellebore has a modeling effect that reduces the level of anxiety and depression.

Chronic recurrent aphthous stomatitis (CRAS) is a disease of the oral mucosa, characterized by the appearance of specific round aphthous forms with hyperemic corolla, covered with grayish-yellow plaque against the background of inflamed mucous membrane, which violates the oxidative homeostasis of oral fluid and the body as a whole.The aim of our study was to reveal the dynamics of free radical processes in oral fluid of patients with chronic recurrent aphthous stomatitis on the background of the first stage of antiseptic therapy with analgesics in order to determine the optimal treatment tactics for this condition. In order to achieve the set objective we had to solve the following tasks: to evaluate the functional activity of free radical processes in the oral liquid of patients with CPAS on the background of antiseptics (chlorhexidine, octenisept, furacilin, myramistine) and anaesthetic (Camistad gel) application for 7 days.Materials and Methods. During the study the oral fluid of 120 people diagnosed with CPPS was studied, divided into 4 groups equally: Group 1 – control, patients used the antiseptic chlorhexidine for gargling; Group 2 – patients with CPPS therapy with octenisept; Group 3 – patients with CPPS therapy with furacilin; Group 4 – patients with CPPS therapy with miramistine. For pain relief, patients in all groups used Kamistad gel. Analysis of free radical processes in oral fluid of patients was carried out before the study and on the 7th day of therapy by determining products of oxidative modification of biomolecules on the basis of quantitative evaluation of stained complex with thiobarbituric acid (TBA), maximal flash (MVHL) and area (PCL) of H2O2-induced luminol-dependent chemiluminescence using LT-01 chemiluminometer ("Horos" "Joint Venture Soviet-Swedish Company"). Concentration of diene conjugates and malonic dialdehyde was also determined to estimate enzymatic part of oxidative homeostasis.Results of the study. Results of the researches permit to conclude that at chronic recurrent aphthous stomatitis enzymatic activity of an oral liquid changes. According to the presented data the initial values of concentration of TBK-RP, maximal flash of oral chemiluminescence, area of oral chemiluminescence and concentration of MDA and DC in the control group and three experimental groups reliably differ from the data received on the 7th day of the research. Significant decrease of the studied indexes of oral liquid testifies to the efficiency of the first stage of therapy of aphthous stomatitis by antiseptic preparations and decrease of intensity of oxidative processes in oral liquid. Of all the proposed antiseptics the best efficiency is demonstrated by octenisept, reliably worse are chlorhexidine and myramistine and the least effective in the therapy of CPAS is furacilin.Conclusions: treatment of CPAS with Octenisept in combination with Camistad gel is the most effective in restoration of the disturbed oxilite.

From the modern point of view, dyslipoproteinemia and its clinical manifestation – atherosclerosis – is a complex multifactorial process, which is based on inflammation, and, as a consequence, oxidative stress.The aim of the study was to identify the dynamics of the concentration of diene conjugates and malondialdehyde in the blood and liver of rats of different ages under oxidative stress caused by modeling dyslipoproteinemia with subsequent mechanical injury of skeletal muscle.Materials and methods. The study was carried out on white mongrel healthy male rats 24 months old (120 individuals) and 6 months old (120 adults). All old and young animals were divided into four subgroups within their group, 30 animals each. The animals of the first subgroup in the groups of old and young rats are intact rats. Animals of the second subgroup in each group had a mechanical dissection in the area of the middle third of the calf muscle of the hind limb. Animals of the third and fourth subgroups of each group were subjected to dyslipoproteemia modeling. After the specified time, the animals of the fourth subgroup of both groups were injured in the middle third of the calf muscle of the hind limb.Conclusions. Mechanical injury of the calf muscle in combination with dyslipoproteemia is characterized by intense oxidative stress and leads to an increase in the concentration of malondialdehyde and diene conjugates in the liver and blood tissues of rats, and in old animals these processes are more pronounced than in young ones.

Currently, there is a steady increase in morbidity and mortality from acute cerebrovascular conditions, which are based on vascular ischemic manifestations, which are systemic in nature. At the heart of the root cause of any ischemic process – heart attack, stroke, hypertension – is atherosclerosis and dyslipoproteinemia. One of the biomarkers of this pathological process is oxidative stress.The purpose of the study: to analyze the dynamics of the activity of glutathione peroxidase and glutathione reductase in the blood and liver of rats of different ages under oxidative stress caused by modeling dyslipoproteinemia followed by mechanical injury to the skeletal muscle.Materials and methods. The study was conducted on outbred healthy male rats, divided into two groups according to age: the first group (c) – 24-month-old (old) rats, weighing 230–250 grams in the amount of 120 pieces and the second group (m) – 6-month-old (young) rats, weighing 190–210 grams in the amount of 120 pieces, kept under standard vivarium conditions. All rats were divided into four subgroups within their group, 30 animals each. Animals of the first subgroup in each group (1s, 1m) are intact (old and young) animals, to which no effects were applied. Animals of the second subgroup (2c, 2m) (regeneration control, old and young) had a mechanical dissection in the region of the middle third of the gastrocnemius muscle of the hind limb. Animals of the first and second subgroups were on a standard vivarium diet and had free access to water and food. Animals of the third (3s, 3m) and fourth (4s, 4m) subgroups of each group were subjected to dyslipoproteinemia modeling for 63 days and received a high-carbohydrate and high-fat diet with an increased fat content of up to 30% by weight of dry matter and replacement of drinking water with a 20% fructose solution. After the specified time, the animals of the fourth subgroups of both groups were injured in the middle third of the gastrocnemius muscle of the hind limb.Conclusions. Against the background of dyslipoproteinemia, oxidative stress occurs in the tissues of young and old rats, which is reflected by a decrease in the activity of enzymes of the glutathione system. Mechanical injury of the calf muscle in combination with dyslipoproteinemia aggravates oxidative processes against the background of inflammation and leads to an even more intense decrease in the activity of glutathione peroxidase and glutathione reductase in the liver and blood tissues of rats, and in old animals these processes are more pronounced than in young ones.

As the body ages, free radical processes intensify and the risk of various age-related diseases increases, including memory impairment, as exchange processes in nerve cells deteriorate. The internal antioxidant system, capable of neutralizing free radicals, is not always able to cope with the growing load, and then the supply of antioxidants from outside is necessary. A source of biologically active substances possessing antioxidant activity are plant extracts possessing a pronounced therapeutic effect combined with a minimum of side effects. The purpose of our study was to study the learning and memory of the offspring of rats that received aqueous plant extracts as an additional load. The study of the learning and memory of the offspring of rats that received aqueous plant extracts of Ginkgo biloba, Centella asiatica, Eleutherococcus and a mixture of aqueous extracts of Ginkgo biloba and Centella asiatica was performed on 4-month-old animals, obtained in an experiment from 15 males and 50 females, which in the course of 30 days water extracts were obtained in a dose of 30 mg/100 g of body weight in a volume of 1 ml. The study was carried out with the help of the test "Passive escape with negative (painful) reinforcement". Conclusions: the offspring of rats that received as an additional load intragastric mixture of aqueous extracts of Ginkgo biloba and Centella asiatica are characterized by the best indicators of learning and memory, compared to the offspring of animals of the control group, and rats that received aqueous extracts of Ginkgo biloba, Centella asiatica and Eleutherococcus separately.

Rats are attractive for various kinds of experiments aimed at studying the effect of substances on metabolism and other components of homeostasis. The use of biologically active substances of natural origin offers great opportunities for modulation of physiological processes in the body, increases the body's resistance, facilitates the clinical course of many environmentally caused diseases and has virtually no negative side effects. Purpose of the study: to study the peculiarities of postnatal physical development of the offspring of rats receiving intragastric aqueous plant extracts as an additional load. The experiment was carried out on sexually mature rats (50 females and 15 males), which were divided into 5 groups of 13 rats each. The groups received various compositions of aqueous plant extracts daily for 30 days at a dose of 30 mg/100 g of animal body weight. The animals were then mated, and the offspring were obtained and subjected to examination. Conclusion: loading rats with aqueous plant extracts promotes intensification of the postnatal physical development of the offspring, and the greatest efficiency is observed when using a mixture of aqueous extracts of Centella asiatica and Ginkgo biloba, rather than when using them separately.

The aim of the study was to investigate reparative processes and immune mechanisms in rat liver tissues against the background of loading with aqueous extracts of blackberry and common sawfly and induced oxidative stress. 120 rats were used in the experiment. According to group affiliation animals received aqueous extracts of common and blackberry in a dose of 50 mg/100g of weight, 1.5 ml daily for 30 days, and animals of the control group received distilled water in the same mode. Starting from 30 days of the experiment, rats were injected with CCl4 for 6 days. On the 37th day of the experiment, rats were killed according to ethical standards. The number of sinusoidal cells was counted in liver tissues. The content of cytokines in liver homogenates and blood plasma of rats was determined by enzyme-linked immunosorbent assay. Conclusion. Aqueous extracts of fir and blackberry modulate to different degrees the functional state of sinusoidal cells in early periods of toxic exposure to tetrachloromethane, which contributes to the early resolution of the inflammatory process. Exposure of aqueous extracts of fir and blackberry to sinusoidal cells changes the production of regulatory factors, which compensates the speed of recovery processes after toxic exposure.

The interaction of warm-blooded organisms with the environment is always reflected in the homeostatic equilibrium of metabolic processes. The dynamics of redox processes occurring in the body is primarily reflected in hematological indices. The aim of the investigation was to study reactive changes of morphological and biochemical blood composition in rats against the background of quercetin load. Objectives: to analyze the dynamics of morphological and biochemical composition of animal blood at the background of intragastric loading with quercetin in the form of oil solution during 30 days. The study was performed on 80 white mongrel male rats weighing 190-210 g, which were divided equally into control (intact) and experimental groups. The study of reactive changes in the morphological and biochemical composition of the blood of rats under the influence of quercetin was conducted in the dynamics before the experiment, as well as on 1, 3, 5, 7, 10, 15, 20, 25 and 30 days of experiment. It was found that against the background of additional loading with oil solution of quercetin in rats there were reactive changes in the morphological composition of the blood, which are reflected in the increased number of red blood cells, concentration of hemoglobin and leucocytes within the physiological norm, as well as changes in the biochemical composition of the blood, expressed in increased concentration of albumin and decreased concentration of albumin fractions in the rats of the experimental group compared with intact animals.

The article presents the results of experimental studies on the effect of micro-irrigation methods (drip irrigation with the surface laying of irrigation pipelines (IP) and subsoil drip irrigation with laying of IP at a depth of 30 cm) on the species and quantitative composition of weeds. The variant with a natural moisture supply (without irrigation) served as a reference area. Field research was conducted in the period 2020-2021 on the lands of the Brylivs’ke experimental field of the Institute of Water Problems and Land Reclamation of NAAS (Dry Steppe subzone) in sunflower and chickpea crops. Monitoring of the number and species composition of weeds was carried out by applying the recording framework by the method of the Institute of Plant Protection of NAAS during the third decade of May and the third decade of August. Based on the results of experimental research, it was proved that the irrigation methods (and hence the conditions of moisture supply) reliably influenced the degree of weed development in sunflower and chickpea crops. It was specified that the implementation of subsoil drip irrigation on average over the years of research reduced the degree of weed development in sunflower and chickpea crops by 1,65 and 1,55 times, respectively, compared to the typical surface laying of drip irrigation pipelines. Ultimately, that reduced the pesticide load on the field agro-ecosystem by reducing the number of herbicide treatments of crops by an average of 33-50 %. The species composition of weeds was not significantly affected by the method of irrigation. In addition, the researchers have shown that, regardless of the irrigation method, weed development in crops significantly reduced the productivity of the investigated crops: sunflower by 18,0-21,2 % and chickpea by 27,9-29,7 %. At the same time, in non-irrigated conditions, the degree of weed development had a greater impact on crop yield; thus, yield reduction in the reference variant without irrigation was 24,6 % for sunflower and 30,0 % for chickpeas.

The accuracy of calculation methods for determining the evapotranspiration (ET) of corn for grain under drip irrigation in the steppe of Ukraine was established. A comprehensive assessment of calculation methods for soil optimal water regime formation during different growth phases of maize plants was carried out. The accuracy of the estimated value of evapotranspiration was determined by the mean absolute percentage error (MAPE). It has been proven that the use of calculation methods without taking into account the climatic conditions of Southern Ukraine leads to a significant error in determining the actual evapotranspiration. By the Penman-Monteith method, the MAPE of 16.3-26.9% corresponds to the good and satisfactory accuracy of the chosen calculation model. Using the methods of A.M. and S.M. Alpatyev as well as D.A. Stoyko the MAPE increased to 22.2-39.7% and 20.8-29.1%, respectively, which proved their satisfactory accuracy. The calculation method of M.M. Ivanov ensured the MAPE of 48,7-76,8%; that is unsatisfactory calculation accuracy. Adapted crop coefficients Kc for the conditions of the South of Ukraine increased the accuracy of calculating ET by the Penman-Monteith method by an average of 2,2 times, D.A. Shtoyko and A.M. and S.M. Alpatiev by 1,9 and 2,2 times, and M.M. Ivanov by 4,4 times. An analysis of the MAPE using various calculation methods for determining the evapotranspiration of corn for grain under drip irrigation showed that the Penman-Monteith method provides the smallest error (MAPE = 9.1%), which corresponds to high prediction accuracy. In a wet year, the accuracy of ET determination decreases by all methods, which indicates an increase in the MAPE: by Penman-Monteith and D.A. Shtoyko - up to 11.9% and 18.7%, respectively, and the determination accuracy decreases to category “good”. When calculating using the methods of A.M. and S.M. Alpatiev and M.M. Ivanov the MAPE increased to 23,3% and 21,5%, respectively, and the accuracy of ET determination was satisfactory.

As a result of mechanical trauma to the eye and damage to the blood-ophthalmic barrier, an inflammatory process occurs and, as a result, oxidative stress is a state of the body that develops against the background of an overproduction of free radicals, with a violation of the effectiveness of antioxidant protection. The aim of the study was to study the dynamics of oxidative stress coefficients for the integral assessment of the antioxidant status of rat liver tissues under oxidative stress induced by mechanical eye trauma. The study was carried out on outbred white sexually mature healthy male rats of six months of age, weighing 220–240 g in the amount of 150 pieces. For the integral assessment of oxidative homeostasis in rats, the coefficients of oxidative stress were used: a coefficient expressing the ratio of catalase activity to SOD activity; antioxidant-prooxidant index (API), which expresses the ratio of catalase activity to MDA concentration; the coefficient of the ratio of the concentration of MDA to the concentration of DC and the local antioxidant index (LAI), which is the ratio of the product of the activities of catalase and SOD to the concentration of MDA. The study found that the antioxidant status of rat liver tissue under oxidative stress caused by mechanical trauma of the eye is most effectively stabilized by standard therapy of mechanical trauma of the eye with the addition of quercetin in the form of injections.

There has been a long-standing expectation that the optical-resolution embodiment of photoacoustic tomography could have a substantial impact on gastrointestinal endoscopy by enabling microscopic visualization of the vasculature based on the endogenous contrast mechanism. Although multiple studies have demonstrated the in vivo imaging capability of a developed imaging device over the last decade, the implementation of such an endoscopic system that can be applied immediately when necessary via the instrument channel of a video endoscope has been a challenge. In this study, we developed a 3.38-mm diameter catheter-based, integrated optical-resolution photoacoustic and ultrasonic mini-probe system and successfully demonstrated its intra-instrument channel workability for the standard 3.7-mm diameter instrument channel of a clinical video endoscope based on a swine model. Through the instrument channel, we acquired the first in vivo dual-mode photoacoustic and ultrasonic endoscopic images from the esophagogastric junction of a swine. Further, in a rat colorectum in vivo imaging experiment, we visualized hierarchically developed mesh-like capillary networks with a hole size as small as ~50 µm, which suggests the potential level of image details that could be photoacoustically provided in clinical settings in the future.

Mechanical eye injury and damage to the blood-ocular barrier cause inflammation resulting in oxidative stress, which, in turn, triggers myocardial ischemia, since the heart's need for oxygen exceeds its supply. A rapid decrease in the oxygen concentration in ischemic tissues causes a switch from oxidative to anaerobic metabolism, when energy deficit initiates a chain of physiological processes. The discovery of the molecular mechanisms underlying the manifestation of oxidative stress in the cardiac tissues will enable the development of effective therapeutic approaches to such condition. Objective: to analyze the dynamics of glutathione peroxidase (GP) activity in cardiac tissues of rats in response to oxidative stress caused by mechanical eye injury.Materials and methods. In our experiment, we used 150 healthy white mature (8-month old) male rats weighing 190–210 g and kept under standard conditions in a vivarium. GP activity was evaluated before the experiment and then on days 1, 3, 5, 7, and 14. Nonparametric statistical analysis was used in this study. Conclusion. GP activity in cardiac tissues of rats during oxidative stress caused by mechanical eye injury was most effectively stabilized by standard treatment for mechanical eye injury plus injections of quercetin.

Prevention and replacement of dentition defects is one of the most important tasks of dentistry. In this case, modern grafting methods are used; implantation is one of such methods. Despite modern technologies, this method causes complications, the most common of which are sinusitis (45.3 %), neuritis (35.5 %), and perimplantitis (19.2 %).

Mechanical trauma of the eye is an example of a limited injury in which systemic changes in the immune system occur. The aim of the study was to investigate the dynamics of morphological manifestations of traumatic inflammation in experimental mechanical trauma of the eye with the inclusion of quercetin in the schemes of experimental therapy. The experiment was conducted on male mongrel rats of six-month age, weighing 220-240 g in the number of 120 animals. All animals were given a penetrating wound of both eyes. Group 1 animals were not treated for mechanical ocular trauma. Group 2 rats received standard therapy for eye injury, group 3 animals received standard therapy with the addition of quercetin injections intraperitoneally, and group 4 animals received quercetin injections only. To obtain macro preparations of the eyeball, adjacent tissues and subsequent preparation of histologic preparations of both eyes, the head of each animal was fixed in a solution of 10% neutral formalin. Histologic sections were examined using the ocular stereometric grid of G.G. Avtandilov. Conclusions: addition of quercetin injections to the standard therapy of eye trauma promotes intensification of reparative processes, reduction of purulent inflammation intensity and phagocytosis in the remote period, increase in the number of immunocompetent cells in the peri-circumferential zones.