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Despite the known hazards to wildlife, plastic waste to waterways and oceans continues to increase at alarming rates every year. Nanoplastics are a breakdown product of plastic debris in the environment (0.1–100 nm). Their small size renders them bioavailable, and they are likely to accumulate/adsorb persistent organic pollutants, which could increase their toxicity. In this study, we evaluated the effects of nanoplastics and phenanthrene on the early life stages of zebrafish. Zebrafish embryos were exposed to fluorescent nanoparticles and observed with fluorescence microscopy. Polystyrene nanoplastics (80 nm) attached to the embryonic chorionic membrane and were ingested when zebrafish reached 144 h after fertilization, the point at which they first open their mouth, as observed by the fluorescence in their intestines. Exposure alone or in combination with phenanthrene resulted in zebrafish pericardial edema, spinal curvature, increased embryonic heart rate, shortened body length, and increased mortality. Co-exposure to 5 mg/L nanoplastics and 0.1 mg/L phenanthrene caused more negative effects on length, teratogenicity and mortality of zebrafish embryos than the corresponding concentrations of single exposure. This study provides clear evidence that nanoplastics can be ingested by zebrafish larvae, thus future work to assess the toxicological effects is important to marine wildlife management.

Introduction Traditional cigarette use influences cost-benefit decision making by promoting impulsive choice. However, the impact of nicotine exposure via electronic nicotine delivery systems on impulsivity remains unclear. Hence, the present study examined the short- and long-term effects of nicotine vapor on impulsive choice. Methods Twenty-four adult male rats were trained in the delay discounting task to choose between small immediate food rewards and large delayed food rewards. After 24 days of training in the task rats were exposed to vapor containing either 0, 12, or 24 mg/mL of nicotine for 10 days. To validate inhalation of nicotine vapor serum cotinine levels were analyzed on exposure days 1, 5, and 10 using enzyme-linked immunosorbent assay. Following vapor exposure, rats were retrained in the discounting task until rats displayed stable responding and the effects of nicotine vapor on choice preference were assessed. Results Rats exposed to 12 and 24 mg/mL nicotine vapor displayed higher serum cotinine levels than control rats exposed to 0 mg/mL vapor. There were no differences in impulsive choice between any vapor exposure groups when tested 15 days after exposure, across 6 days of stable responding, suggesting that nicotine vapor does not have long lasting effects on impulsive choice. Interestingly, a subsequent nicotine vapor challenge revealed short-term increases in impulsive choice immediately following a single exposure to 24 mg/mL nicotine vapor, relative to choice preference immediately following exposure to 0 mg/mL vapor. Conclusions These results suggest that exposure to nicotine vapor causes immediate, short-term increases in impulsive choice. Implications E-cigarette use is increasing at an alarming rate, particularly among adolescents and young adults. This is concerning given the lack of research into the effects of nicotine vapor exposure on the brain and behavior. The present study describes a viable rodent model of human e-cigarette use and suggests that exposure to nicotine vapor produces short-term increases in impulsive choice.

Relevance. In light of the popularization of the use of caffeine-containing products, the question of the combined use of caffeine with substances exhibiting a toxic effect remains open. The doses of caffeine, which have a pronounced antidepressant effect, are also insufficiently studied. The aim of the study was to study the effect of repeated administration of caffeine and dioxidine on the behavioral responses of mice in the Porsolt test. Materials and methods. The experiment was carried out on 36 outbred male mice, divided into 6 groups. Experimental groups for 15 days of the study received caffeine at a dose of 40 mg/kg (first) or 100 mg/kg (second), dioxidine at a dose of 200 mg/kg (third), together with caffeine 40 mg/kg or 100 mg/kg, and dioxidine (fourth and fifth groups, respectively). The animals of the control group were injected with saline. To study the behavior, the Porsolt test was carried out, evaluating the following indicators on the 1st, 8th and 15th days of the experiment: the total time of immobilization, active swimming, climb, the number of grooming and shaking off acts. Results . The administration of caffeine at a dose of 40 mg/kg caused an increase in the time of active swimming and a decrease in the duration of immobilization on the 8th and 15th days. When caffeine was used at a dose of 100 mg/kg, an increase in the time of active swimming was noted with a single exposure, with an experiment duration of 8-15 days, an increase in the duration of immobilization was observed. Dioxidine caused a significant decrease in the time of active swimming and an increase in the duration of immobilization during all days of the experiment. The combined use of caffeine (40 mg/kg and 100 mg/kg) and dioxidine on the 1st day led to a decrease in immobilization and the time of active swimming. In both groups, 100 % animal mortality was observed by the 15th day. Conclusion. The results of the study indicate the presence of an antidepressant effect in caffeine at a dose of 40 mg/kg on the 8th and 15th days of the experiment and the absence of this effect in caffeine at a dose of 100 mg/kg with a duration of administration of 8-15 days. The use of dioxidine led to the absence of antidepressant activity and the presence of the opposite effect. The combined administration of caffeine (40 mg/kg and 100 mg/kg) and dioxidine led to 100 % mortality in the experimental groups by the 15th day of the experiment

In general, memory of highly negative and even traumatic events can distort. However, the effect of misinformation exposure on such memories requires further investigation given the inconsistent past findings. With two experiments, we investigated: (1) whether misinformation distorts memory for highly negative analogue events, (2) whether memory distortion is increased for more emotional and potentially traumatic details compared to unemotional details, and (3) whether repeated misinformation exposure further increases memory distortion for highly negative events compared to single exposure, a possibility that has not been investigated to our knowledge. In both experiments, participants viewed a trauma analogue film with some scenes removed. Twenty-four hours later, they were given three "eyewitness" reports describing the film's events. To manipulate misinformation repetition, either zero, one, or all three of the reports described removed scenes. To determine whether memory distortion is increased for emotional details, half of the removed scenes were more traumatic than the other half. Participants exposed to misinformation falsely remembered more removed scenes compared to participants who were not exposed to misinformation. Further, memory distortion was increased for emotional (vs. unemotional) aspects of the film. Repeated misinformation exposure, however, did not lead to significantly higher error rates compared to single exposure. The lack of perceptual overlap between our written misinformation and film test items may have limited false memories even with repeated misinformation. Alternatively, the repeated vs. single misinformation effect may exist but be very small, as suggested by our raw means and effect sizes.

Summary. Diseases of the respiratory organs of children, occurring with obstructive syndrome, represent one of the most serious problems in terms of transition to chronic forms. The chronic process is accompanied by a decrease in pulmonary ventilation, which leads to the search for effective methods of complex therapy of diseases. The purpose of this study was to evaluate the dynamics of acoustic indicators of pulmonary ventilation in children with bronchial asthma, against the background of non-invasive non-thermal microwave radiation. Materials and methods. 122 children with bronchial asthma aged from 3 to 17 years were examined. 113 patients underwent a single session of non-invasive microwave therapy with the Aster device. Comparison of acoustic characteristics of pulmonary ventilation was carried out taking into account the severity of the disease and the age of children with bronchial asthma. Acoustic assessment of ventilation function was performed using the computer bronchophonography complex Pattern-01 before the Aster procedure, after 5 and 15 minutes. In 20 (16.4%) patients with bronchial asthma, the dynamics of cough was evaluated against the background of Aster therapy for 7 days. Results. Improvement of bronchial patency was registered in all age groups with mild bronchial asthma. In the group of moderate asthma, exposure to electromagnetic radiation led to a significant reduction in ventilation disorders in children aged 711 years. As patients grow older, as well as with severe bronchial asthma, the smallest dynamics of the parameters of pulmonary ventilation was observed against the background of Aster therapy. The use of electromagnetic radiation in addition to traditional basic therapy for 7 days leads to a faster regression of cough in patients with bronchial asthma. Conclusion. The combination of traditional basic therapy with electromagnetic non-thermal radiation in patients with bronchial asthma reduces obstructive pulmonary ventilation disorders and promotes faster cough regression.

The cannabinoids, Δ9 tetrahydrocannabinol and its analogue, nabilone, have been found to reliably attenuate the intensity and frequency of post-traumatic nightmares. This essay examines how a traumatic event is captured in the mind, after just a single exposure, and repeatedly replicated during the nights that follow. The adaptive neurophysiological, endocrine and inflammatory changes that are triggered by the trauma and that alter personality and behavior are surveyed. These adaptive changes, once established, can be difficult to reverse. But cannabinoids, uniquely, have been shown to interfere with all of these post-traumatic somatic adaptations. While cannabinoids can suppress nightmares and other symptoms of post-traumatic stress disorder, they are not a cure. There may be no cure. The cannabinoids may best be employed, alone, but more likely in conjunction with other agents, in the immediate aftermath of a trauma to mitigate or even abort the metabolic changes which are set in motion by the trauma and which may permanently alter the reactivity of the nervous system. Steps in this direction have already been taken.

Polymeric palladium complexes [(C5H12NO)(PdCl3)]n (I) and [(C10H16NO)2(Pd2Cl6)] (II) were synthesized for the first time and studied by X-ray diffraction. Complexes I and II were found to have moderate toxicity (3rd class of toxicity) and high antitumor and radioprotective activities. Treatment of Lewis lung carcinoma (LLC) with I and II induced statistically significant antitumor and antimetastatic effects exceeding those of cisplatin: the use of I and II retarded the growth of LLC by 60.0%, while cisplatin retarded it by 48.0%. The decrease in the LLC metastasis was 75% upon the action of I, 91.0% in the case of II, and 69.0% for cisplatin. It was shown that II has a clear-cut radioprotective action. On single exposure of mice to a dose of 8.2 Gy, their survival rate was 58.0% versus 4.5% for the control. Fractional exposure to increasing doses (2.5, 3, and 3.5 Gy) resulted in 75.0% survival rate versus 33.0% for the control.

Hypoxia is the main link in the taxis pathogenesis to most extreme factors. It occurs in many pathological processes. The aim of the work was to study the hemostatic system in rats under a single exposure to submaximal and maximum hypercapnic hypoxia. Materials and Methods. The experiment enrolled 40 Wistar male rats. Single 20-minute hypercapnic hypoxia (HH) was modeled by placing the animals into a chamber with a gas mixture: submaximal HH: O2 – 9 %; CO2 –7 %; maximum HH: O2 – 5 %; CO2 – 5 %. Results. Single submaximal HH was accompanied by a decrease in the platelet number under a constant level of their aggregation activity. Hypercoagulable shift was observed along the internal pathway and at the final stage of coagulation against the decrease in fibrinogen concentration. AT III level decreased, however, there were no changes in blood APR. Single maximum HH led to more pronounced coagulable shifts. Platelet hemostasis responded by a decrease in the platelet number with a simultaneous increase in their aggregation activity. As for coagulation hemostasis, hypercoagulation was recorded at all stages of coagulation. At the same time, fibrinogen concentration in blood plasma decreased, and the level of soluble fibrin-monomer complexes (SFMCs) significantly increased. The authors reported an increase in plasma fibrinolytic activity. Conclusion. Thus, upon a single exposure to submaximal HH, hypercoagulation was not yet accompanied by thrombinemia markers. At the same time, the danger of thrombotic state development remained, since the hypercoagulable shift was recorded against a decrease in blood plasma anticoagulant activity. A further increase in HH intensity was accompanied by deteriorating hemostatic functions of experimental animals, which could be described as a state of thrombotic readiness. A decrease in the anticoagulant level in response to maximum HH exacerbated thrombosis risks. Keywords: hemostasis, hypercapnic hypoxia. Гипоксия выступает в качестве основного звена патогенеза ответной реакции организма на воздействие большинства экстремальных факторов и встречается во многих патологических процессах. Цель работы – изучить состояние системы гемостаза у крыс, подвергшихся однократному воздействию гиперкапнической гипоксии субмаксимальной и максимальной интенсивности. Материалы и методы. В эксперименте использовались крысы-самцы (40 особей) линии «Вистар». Однократная 20-минутная гиперкапническая гипоксия (ГКГ) моделировалась путем помещения животных в камеру, в которую подавалась смесь газов: ГКГ субмаксимальной интенсивности – 9 % О2, 7 % СО2; максимальной – 5 % О2, 5 % СО2. Результаты. Однократная ГКГ субмаксимальной интенсивности сопровождалась снижением количества тромбоцитов при неизменном уровне их агрегационной активности. Гиперкоагуляционный сдвиг отмечался по внутреннему пути и на конечном этапе свертывания на фоне снижения концентрации фибриногена. Уровень АТ III снижался, однако изменений со стороны АРП крови зафиксировано не было. Однократная ГКГ максимальной интенсивности приводила к более выраженным коагулологическим сдвигам. Тромбоцитарный гемостаз отреагировал снижением количества тромбоцитов при одновременном повышении их агрегационной активности. Со стороны коагуляционного гемостаза регистрировалась гиперкоагуляция на всех этапах свертывания. При этом концентрация фибриногена в плазме крови снижалась, уровень РФМК значительно повышался. Было зарегистрировано повышение фибринолитической активности плазмы крови. Выводы. Таким образом, по завершении однократного воздействия ГКГ субмаксимальной интенсивности гиперкоагуляция еще не сопровождалась появлением маркеров тромбинемии. При этом опасность развития тромботического состояния сохранялась, поскольку гиперкоагуляционный сдвиг регистрировался на фоне снижения антикоагулятной активности плазмы крови. Дальнейшее повышение интенсивности воздействия ГКГ сопровождалось ухудшением гемостатического статуса экспериментальных животных, что может быть охарактеризовано как состояние тромботической готовности. Снижение уровня антикоагулянта в ответ на ГКГ максимальной интенсивности увеличивало риск развития тромбообразования. Ключевые слова: гемостаз, гиперкапническая гипоксия.

Toxic or noxious prey often signal their unpalatability through aposematic coloration, and the evolution of aposematism has become a model system in evolutionary behaviour. Aposematic colours are not only easily recognized by predators, but, for many predators, aposematism enhances learning and memory retention. In this study, we used a visually oriented, insectivorous agamid lizard, Diploderma swinhonis, to test whether aposematic coloration enhances lizards’ ability to detect and remember distasteful prey. We exposed lizards to quinine-flavoured crickets, Gryllus bimaculatus, that were dyed with colours generally regarded as aposematic (red) and nonaposematic (green). After a single exposure, lizards readily learned to reject both red and green crickets, but in subsequent trials they were more hesitant to attack red than green ones. However, the lizards remembered both types of prey for up to 60 days and showed a similarly high rate of generalizing that aversion from coloured to noncoloured crickets. Our results demonstrate that visually hunting lizards exhibit nuanced patterns of learning and memory in foraging tasks and make ideal subjects for experimental work on aposematism.

In this study, we explored the possibility of photo- and photo-thermal depletion of deep traps in anion-deficient corundum (α-Al2O3-δ) crystals and luminescent storage dosimeters on their basis. As a result of repeated normal use or a single exposure to high-dose radiation, these traps become filled, which reduces significantly the informative response of thermally and optically stimulated luminescence (TL and OSL) due to the depletion of the main dosimetric trap. It has been found that effective photodepletion of the deep trap causing the 830 K TL peak, whose filling affects the informative TL and OSL responses most of all, is only possible in α-Al2O3-δ crystals and unpacked TLD-500 detectors on their basis. In the majority of cases, including practically important ones associated with the restoration of the dosimetric properties of widely employed α-Al2O3-δ dosimeters, photothermal depletion proves to be more effective.

Toxicity and hazard assessment of dioctyl terephthalate (DOTP) was performed in acute, subacute, and chronic experiments, and its principal toxicometry parameters were determined.It was found that on single exposure DOTP exhibits low toxicity and hazard. No resorptive and irritant effects on skin and mucous membrane of eyes were detected in animal experiments. The single inhalation exposure threshold limit value was set at 300 mg/m3, based on the results of monitoring of the functional state of the central nervous system and myocardium and hematological parameters.Thirty-day subacute experiments (oral administration, inhalation exposure, and skin applications) revealed no accumulation of the compound.Four-month chronic exposure to DOTP aerosols (concentration 96,8 mg/m3) caused disorder of the functional state of the central nervous system and myocardium, changes in the hematological and biochemical parameters, gas and acid-base status of the blood, and morphological changes in the lungs and heart. Embryotoxic, genotoxic and gonadotoxic effects were not detected.The chronic inhalation exposure threshold limit value for DOTP (Limch) was set at 18,6 mg/m3, and the concentration of 3,4 mg/m3 was found to be ineffective.The maximum allowable concentration of DOTP in the air of the working area was set at 3,0 mg/m3, hazard class 3.

Multi-wavelength diffraction imaging is a lensless, high-resolution imaging technology. To avoid multiple exposures and enable high-speed data collection, here an innovative setup for the single-exposure multi-wavelength diffraction imaging based on a blazed grating is proposed. Since the blazed angle varies with the wavelength, the diffraction patterns for the individual wavelengths can be separated from each other and recorded in a single measurement at one time. A method of high-precision position alignment between different wavelength patterns is proposed in our system to achieve good image quality and high resolution. Experiments on a phase-only USAF resolution target and biological samples were carried out to verify the effectiveness of our proposed method. This proposed setup has such advantages as a simpler structure, fast recording, and algorithm robustness.

Misinformation has been a pressing issue since the beginning of COVID-19 pandemic, threatening our ability to effectively act on the crisis. More recently, the availability of vaccines in developed countries has not always translated into high vaccination rates, with online misinformation often presented as the culprit. Yet little is known about the actual effects of fake news on behavioural intentions. Does exposure to misinformation about COVID-19 vaccines indeed affects people’s intentions to receive such a vaccine? This paper attempts to answer this question through three preregistered experiments (N=3463). In Study 1, participants (n=1269) were exposed to fabricated pro- or anti-vaccine information or to neutral true information, and then asked about their intentions to get vaccinated, alongside a few other behavioural intentions. In Study 2, participants (n=1863) were exposed to true pro- and anti-vaccine information, while Study 3 (n=1548) compared the effects of single and multiple exposures to novel misinformation about COVID-19 vaccines. The results showed that exposure to false information on the vaccines did not affect the participants’ intentions to get vaccinated, even when multiple exposures led them to believe that the headlines were more accurate than in the single exposure conditions. An exploratory meta-analysis of studies 1 and 3 (n=2683) showed that exposure to false information about COVID-19 vaccines, regardless of whether it was in favour of or against vaccines, increased vaccination intentions. We conclude by cautioning researchers against equating exposure to misinformation or perceived accuracy of false news with actual behaviours.

Objective: The objective of the study was to evaluate the relationship between frequency of exposure to general anesthesia before the age of 3 and subsequent risk of diagnosis for attention-deficit hyperactivity disorder (ADHD).Method: We searched PubMed, Embase, Web of Science, and Cochrane Library database for eligible inclusion in the meta-analysis. The indicated outcomes were extracted from the included studies, and the combined effects were calculated using the RevMan software 5.3.Results: Compared with no exposure to general anesthesia, single exposure to general anesthesia did not increase the risk of ADHD for children before the age of 3 [hazard ratio (HR): 1.14, 95%; confidence intervals (CI): 0.97–1.35; p = 0.11; I2 = 0%], while multiple exposures to general anesthesia did increase the risk of ADHD (HR: 1.83; 95% CIs: 1.00–3.32; p = 0.05; I2 = 81%).Conclusion: Multiple, but not single, exposures to general anesthesia in children before age of 3 increased the risk of ADHD.

This work describes a newly developed experimental mouse model reproducing features of blast-induced neurotrauma (BINT), induced in operationally relevant manner using a compressed air-driven shock tube. Mild BINT (smBINT) was induced by one exposure to a low-intensity blast (LIB), whereas subconcussive BINT (rscBINT) was caused by repeated exposures to LIB.To mimic an operational scenario when a soldier is standing when exposed to blast using a quadruped experimental animal (mouse), a whole-body holder was developed to position mice in a bipedal stance, face-on toward the pressure wave generated in a shock tube. This restraint avoids ‘bobble head’ movement, thus prevents tertiary blast effects, and allows administration of fast-acting inhaled anesthetics via nose cone.Using this model, we established and validated paradigms for primary blast-induced mild and repetitive traumatic brain injuries Our results showed that a single exposure to 69 kPa (10 psi) was capable of inducing smBINT, whereas three-rounds of exposure to 41 kPa (6 psi) caused rscBINT.Mice recovered rapidly from both types of BINT without prolonged neurological dysfunction. Mild superficial pathology was found predominantly in the lungs 24h after injury, with equivalent pathology after smBINT or repetitive rscBINT. The Purkinje layer of the cerebellum exhibited neuronal damage persisting up to 7d. Similar to some other models as well as clinical findings, this model reproduces blast-induced cerebellar pathology. In conclusion, this model positioning mice in a bipedal stance and facing front-on toward the shockwave provides realistic representation of operational scenarios and reproduces militarily-relevant smBINT and rscBINT in the laboratory.

Research has shown that seeing positive facial expressions (FEs) towards food increased children's desire to eat foods rated as disliked. However, the effect of adults' positive FEs whilst eating a raw vegetable on children's acceptance and intake of nutritious foods that are less preferred (e.g., vegetables) remains to be established. This study aimed to examine the effect of models' FEs eating raw broccoli on children's acceptance and intake of raw broccoli. 111 children aged 4–6 years (64 male, 47 female) were randomised to watch a video of unfamiliar adult models eating raw broccoli with a positive or neutral facial expression (FE), or a non-food control video. Children's acceptance and intake of raw broccoli was assessed. Data about parent and child characteristics was provided by parents. There was a main effect of FE type on children's frequency of tastes (p = .03) and intake of broccoli (p = .02). Children who were exposed to models eating broccoli with positive FEs had greater frequency of tastes (p = .04) and intake of broccoli (p = .03), than children in the control condition, but not compared to children in the neutral FE condition (p > .05). There was no effect of positive FEs on children's willingness to try broccoli (p > .05). These findings suggest that observing others enjoy a commonly disliked vegetable can encourage children's tastes and intake of the vegetable. Thus, exposing children to others enjoying vegetables could be a useful strategy for encouraging healthier eating in children. Further work is needed to determine whether a single exposure is sufficient and whether these effects are sustained over time.

The primary objective was to assess the effect of general anaesthesia versus regional anaesthesia in a single exposure before the age of 2 years on the development of long-term behavioural changes in children.The study was conducted between January 2014 and March 2015. Medical records of eligible children were reviewed. Then, parents of children who were included in the study were contacted and asked to visit the Outpatient Department to fill the Eyberg Child Behaviour Inventory questionnaire to measure behavioural changes in children. Children who were exposed to regional or general anaesthesia for surgery between January 2002 and December 2006 were included. Data collected were age and weight at the time of the first anaesthesia exposure and surgery duration. Chi-square test, t-test and multivariate analysis were used.In total, 394 children were exposed to anaesthesia before the age of 2 years. Among the 168 patients who were exposed to general anaesthesia, 44 children (26.2%) developed behavioural abnormalities compared to 12 out of 226 patients (5.3%) who were exposed to regional anaesthesia (P-value0.0001). Exposure to anaesthesia before age of 2 years increases the risk of developing behavioural disorder when surgery is accompanied by general anaesthesia, younger age at time of exposure, and longer surgery duration (P-value0.0001, 0.001, 0.038 respectively).Regional anaesthesia showed much lesser effect on children's behaviour compared to general anaesthesia. The incidence of behavioural disorder is increased with the use of general anaesthesia, younger age of the patient at time of exposure, and longer surgery duration.

The focus of this paper is on an examination of the effectiveness of a 1-h workshop designed to teach poetry as a coping tool for children and adolescents in crisis and psychiatric facilities. This study was designed to measure poetry self-efficacy, belief in the usefulness of poetry as a coping tool, and changes in feelings of isolation and loneliness. Overall, the results of this study suggest adolescents and children in crisis centers and inpatient units may both enjoy and benefit from a single exposure to poetry.

Metallic helical metamaterials have become the prominent candidates for circular polarizers and other optical-chiral devices as they exhibit strong circular dichroism at a broad operation bandwidth. However, the rapid fabrication of an intertwined double helix with multiple pitch numbers and excellent mechanical strength, electrical conductivity and surface smoothness remains a challenge. We propose and realize the single-exposure femtosecond laser photoreduction of a freestanding, three-dimensional silver double-helix microstructure by the double-helix focal field intensity engineered with a spatial light modulator. At the same time, the photoreduction solution and the laser repetition rate are optimized to further tackle the surface roughness and the thermal flow problems. As a result, the silver double-helix array with the enhanced quality exhibits pronounced optical chirality in a wide wavelength range from 3.5 to 8.5 μm. This technique paves a novel way to easily and rapidly fabricate metallic metamaterials for chiro-optical devices in the mid-infrared regime.

—This work studies the influence of mechanical properties on the durability of cutting tools made of high-speed steel R6M5 under production conditions and their relationship with indicators of changes in the “defectiveness” of the structure (density of dislocations, size of mosaic blocks, crystal lattice microdistortion), which occurred as a result of a single exposure to a high-energy laser pulse. It is shown that when assigning optimal modes of volume pulsed laser hardening (VPLH) (energy and duration of a laser pulse, laser beam diameter, distance from the irradiation point to the main cutting edge), the results of X-ray analysis can be used, which can significantly improve the technical and economic indicators of the hardening and operation of cutting tools made of high-speed steel Р6М5 in terms of productivity, prime cost and instrumental costs of laboratory research.

The study presents data on the impact of the monopolar radiofrequency method on the morphofunctional state of the skin. Patients were observed with various morphotypes of involute skin changes. 49 patients aged 45 to 55 years were observed. All patients were divided into 3 groups depending on the prevailing morphotype of involute skin changes: fine-wrinkled, deformed, and mixed. In all groups, a single exposure was performed using the monopolar radio frequency method according to the approved Protocol of work in the face area. Objective research methods included ultrasound sonography of the epidermis and dermis, adapted dermatological indices of quality of life (DIQ) and SAN (well-being, activity, mood). The results were evaluated 3, 6 and 12 months after the treatment. The obtained data showed that the high-frequency radio-wave method is more effective in deformational and mixed types of aging compared to small-scale wrinkling.

Aim. To study the effect of repeated stress on blood glucose level in rats with various behavioral characteristics and with different resistance to the development of adverse consequences of negative emotiogenic exposures. Materials and Methods. The animals were initially subjected to open field test to calculate the index of activity. Daily 4-h immobilization of rats in individual plastic cages for 8 days was used as a model of stress. Blood glucose concentration was measured with a glucometer (control measurement and on the 1st, 3rd and 8th days of repeated stress). Results. The basal level of glucose in behaviorally active (stress-resistant) rats was lower than in passive (stress-predisposed) specimens. Repeated exposure of rats to stress resulted in development of hyperglycemia. However, the dynamics of blood glucose concentration was different in specimens with different parameters of behavior. The increase in glucose concentration in active animals was most pronounced after a single exposure. By the 3rd and 8th days of stress exposures, glucose level in these rats progressively decreased (as compared to the 1st day), but remained above the basal level. Passive specimens were characterized by the increase in blood glucose concentration after a single and, particularly, after three-time restraint stress. Glucose content in these animals slightly decreased by the 8th day (as compared to the previous periods), but was above the basal level. Conclusion. The dynamics of abnormalities in carbohydrate metabolism (in particular, changes in blood glucose level) during chronic emotiogenic exposures differed in specimens with different resistance to stress factors. These data illustrate the importance of an indivi-dual approach to studying the pathophysiological mechanisms of progression and development of stress-induced disorders.