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The article presents the results of the analysis of the validity of simplifications and assumptions accepted by researchers in the models of neutron-physical characteristics of fuel-containing materials (FCM) in the "Shelter" object (SO). The analysis and substantiation of the FCM nuclear safety will be one of the important issues during the SO operation for a long time, until the moment of retrieval and disposal of nuclear materials from the ChNPP Unit 4 destroyed in 1986. A significant number of nuclear materials in the SO are uncontrolled, and the geometry of their location is also little known. Therefore, the use of traditional methods of nuclear safety analysis to determine the conditions for reaching criticality in the volume of FCM can lead to significant uncertainties, depending on the assumptions and simplifications made in FCM models. In contrast to traditional nuclear facilities with design characteristics and control systems, there is no possibility to deterministically influence the FCM, and accordingly to determine their dynamic characteristics in the SO. In such conditions, it is necessary to take a responsible approach to obtain and interpret the values of FCM parameters by control systems of the SO. For example, in 1990, one of the neutron flux detectors recorded an abnormal change in the neutron pulse count rate for about 100 hours. This event is often called a “neutron incident”, and it formed the basis of some models, in which the possibility of reaching criticality in one of the FCM clusters is assumed. The article presents the results of the study on the physical possibility of the anomalous event in 1990, as well as the results of the analysis of simplifications and assumptions made in models of FCM criticality. An important result of the conducted research is the justification of the need to include in the FCM criticality model the effects of reactivity on fuel and water temperature, as well as to take into account delayed neutrons.

The aim of the study – determining the immunohistochemical levels of the GFAP, GS and AQP4 in different regions of the human brain in the conditions of liver cirrhosis of different degree. Materials and methods. The study was performed on sectional material of 90 patients who suffered during lifetime from liver non-alcoholic cirrhosis of classes A (n = 30, group “A”), B (n = 30, group “B”) and C (n = 30, group “C”) according to Child–Pugh classification, including 59 (65.55 %) cases with clinical symptoms of I–IV grade hepatic encephalopathy. Cortex, white matter, hippocampus, thalamus, striopallidum, cerebellum, were examined using immunohistochemical method for evaluation of GFAP, GS and AQP4 levels. Results. GFAP expression gradually decreased from classes A to C of cirrhosis. The most expressed GFAP decline was found in class C in the cortex and thalamus (6.74- and 6.23-fold decrease). Contrary to GFAP, GS expression gradually increased along with aggravation of cirrhosis. The most prominent augmentation of GS was related in the cortex and thalamus in “C” group, respectively 4.34- and 4.26-fold increase. AQP4 levels also showed growing mode correlated with cirrhosis aggravation. The highest increase was found in the cortex and thalamus in “C” group (4.25- and 4.34-fold increase, respectively). Starting from class B, altered GFAP, GS, and AQP4 levels showed region-dependent relationships. GS and AQP4 were positively correlated in all 6 studied regions, while the inverse relationships were found between GFAP vs. GS and GFAP vs. AQP4 proteins. Conclusions. As early as in class A of cirrhosis, dynamic molecular alterations are occurred in the brain astrocytes, indicating the progressive development of astroglial remodeling with a violation of its cytoskeleton and redistribution of molecular domains within cells. This phenomenon is region- and time-specific; its signs get stronger with time from class to class, becoming most pronounced in class C. Among studied brain regions, cortex and thalamus are characterized by the most pronounced protein changes. Starting from class B, the remarkable relationship is seen between molecular changes of both direct and inverse type. Simultaneously emerging links might indicate synergistic involvement of these molecules in astroglial remodeling in chronic hepatic encephalopathy. Alterations in the mentioned astroglial molecular complex can serve both as a diagnostic marker of reactive astrogliosis during liver cirrhosis and represent a target for novel therapeutic approaches regarding encephalopathy in cirrhotic patients.

Link for citation: Rofida Hamad Khalifa Hamad, Nikitenkov N.N., Kudiyarov V.N. Calculation of nuclear fuel cladding internal coating thickness for emergency resistant nuclear fuel element. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 6, рр.27-34. In Rus. The relevance of the study lies in the need to create an emergency resistant fuel for nuclear reactors, based on the study of the consequences of accidents in Chernobyl and Fukushima. The specific problem to which the work is devoted is the creation of thin-film chromium coatings on the inside of nuclear fuel element tubes, which is one of the directions for creating an emergency resistant core of a nuclear reactor. The main aim of the research is to determine the minimum thickness of the chromium coating necessary for adequate protection of the inner side of the fuel rod cladding from nuclear fuel fission fragments. Methods: a well-developed (more than 60 years of improvement) and widely known and recognized software package to simulate the physical processes of radiation and accelerated particle transport in solids using Monte Carlo statistics. The determination of the minimum thickness of the chromium coating to ensure protection of the inner side of the fuel element cladding from the main group of high-energy fission fragments of nuclear fuel was carried out on the basis of calculations using the TRIM program (from the SRIM package). 97Tc, 98Mo, 102Ru, 103Rh, 106Pd, 127I, 133Cs were selected as bombarding the coating from their wide range of nuclear fuel fission fragments, as the most high-energy and at the same time, having different chemical properties. Results. It was found that the minimum thickness of chromium required to provide adequate protection of the inner surface of the fuel tube from the main fission fragments of the U235O2 fuel is 9 µm. Experimental data confirming this result are presented.

The reactor model was used to study the accident that destroyed the RBMK-1000 reactor at Unit 4 of the Chornobyl nuclear power plant on 26 April 1996. The model of reactivity accident of the RBMK-1000 reactor is based on equations of nuclear reactor kinetics, taking into account feedback in reactor reactivity. Reactivity changes as a result of both external influences – the movement of regulatory organs, changes in the reactor inlet coolant temperature, – and as a result of feedback by core parameters – changes in fuel temperature, coolant density, and 135Хе concentration. The model takes into account steam generation in the reactor core, which corresponds to the real physics of processes at the RBMK reactor, and allows obtaining simulation results that best match the recorded data and the consequences of the accident process. The study of reactivity accident on RBMK-1000 reactor is carried out for different combinations of values of control rods efficiency; reactivity coefficients by fuel temperature and coolant density; changes in the reactor inlet coolant temperature; the emergency protection time, as well as the reactor power level before closing the turbine generator stop valve. Different reactivity accident scenarios at RBMK-1000 reactor allow us to determine the most unfavorable combinations of external influences on the course of reactivity accident, namely: start time of main coolant pump rundown, time of activation of emergency protection, power level before the closing of turbine generator stop valves. In most reactivity accident scenarios, first of all, the critical values of fuel enthalpy are reached, at which the process of fuel destruction in the fuel element, destruction of the fuel assembly, and assembly channel start. Important results of studies are 1 – determination of the fact that time of activation of emergency protection after the closing of stop valves of turbine generator significantly affects the value of the maximum neutron power that is achieved during a reactivity accident; 2 – determination of the effect of reactor power before the closing of turbine generator stop valves on the course of the accident; 3 – it is not necessary to achieve supercritical on instantaneous neutrons, supercritical on delayed neutrons is enough to start fuel destruction.

The adequacy of recovery processes in myocardial infarction (MI) significantly depends on the state of reactivity of the organism, which, in turn, is determined by the adequacy of neuro-endocrine regulation, in particular, hypothalamic-pituitary-adrenocortical (HPA) and hypothalamic-pituitary-thyroid (HPT) system system.Purpose of the study. To investigate the condition of HPA and HPT in acute experimental MI against the background of different reactivity of the organism.Material and methods. The study was performed on 20 outbred adult dogs weighing 8-12 kg, in which MI was simulated by ligation of the anterior interventricular artery. Animals were divided into three groups (n =5 in each group). The condition of hyperreactivity was caused by the introduction of pyrogenal (group 2), the state of hyporeactivity - the introduction of azothioprine (group 3), in group 1 drugs were not used (state of normoreactivity). In the control group used 5 falsely operated dogs with thoracopericardiotomy. In animals before surgery, on 1, 4, 7, 11 and 15 days in the blood was determined by the content of adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH) , cortisol (Cr), aldosterone (Ald), thyroxine and triiodothyronine. Statistical processing was performed using license packages Statistica 5.5 (Stat Soft Rus), Statistica Neural Networks (Statsoft Inc.).Results. Normoreactive course of myocardial infarction was characterized by primary activation of HPA, which was most pronounced for Cortisol, followed by restoration of ACTH and Aldosterone levels and duration of activation of the central link up to 4 days, peripheral - up to 7-11 days; reciprocal in relation to HPA inhibition of the functional activity of the HPT, most pronounced on the 4th day and lasting up to 15 days. Such changes caused the healing of myocardial infarction through the formation of a full-fledged post-infarction scar. The hyperreactive course of myocardial infarction was characterized by hypersecretion of ACTH with hypercorticism and hyperaldosteronism and less pronounced suppression of HPT with the restoration of its functional activity on the 7th day. The hyporeactive course of myocardial infarction was characterized by a minimally pronounced and delayed up to 4 days activation of HPA with Aldosterone hyposecretion on the 15th day; deep hypothyroidism of both central and peripheral genesis. Impaired reactivity was accompanied by an increase in the area of necrosis and a decrease in the thickness of the heart wall with the formation of postinfarction aneurysm.Conclusions. Desynchronization of necrotic and reparative processes with a change in reactivity leads to a disruption in the relationship between necrosis and repair with the formation of postinfarction aneurysm, which is accompanied by different activities of the HPA and HPT.

An overview of cryotherapy, the processes of adaptation to the low temperatures in particular is presented. The effect of short-term exposure to low temperature alteration indicators of the condition of the body was investigated. The results show that the level of reactivity did not change after cryotherapy. It was found that after cryotherapy the concentration of malondialdehyde in plasma levels of athletes had decreased.

The increase in life expectancy is accompanied by an increase in the number of patients suffering from chronic cerebrovascular diseases with progressive cognitive decline, up to dementia. Therefore, the search for new approaches to studying the disease pathogenesis, prevention and treatment is relevant. We analysed the data on correlation of cognitive characteristics with reactions of the autonomic nervous system (ANS) and ANS-regulated systems in normal aging and in patients with vascular encephalopathy (VE). Reactivity of cerebral blood flow as a result of cortical-ANS interaction was studied, characteristics of cerebral blood flow influencing the interhemispheric energetic processes (studied with direct current potentials of the brain) were analyzed, and correlation of blood pressure and heart rate with cognitive characteristics were assessed. Since the signs of cognitive decline are observed during normal aging and VE, an attempt was made to analyze the dependence of cognitive and ANS functions not only on VE, but also on the age. We showed some specific features of cortical-ANS interaction in groups of patients divided in accordance with small criteria of functional asymmetry. The obtained results are of value for studying VE pathogenesis and for prognosing cognitive impairment in patients with VE.

The present article describes clinical signs of meningococcal disease. It justifies the necessity of its vaccine prevention. The article provides with the historical data on the evolution of inoculants from corpuscular inactivated vaccines to modern chemical polyvalent vaccines. It provides a glimpse of the efficacy of the use of corpuscular vaccines and considers the corresponding implications. The historical overview includes the use of mono-, di-, tetravalent polysaccharide vaccines, and the discussion on the role of bactericidal antibodies in the formation of immunity against meningococcal disease. The article also describes the experience of using polysaccharide vaccines in various countries and in different age groups in randomized clinical trials. It provides with the data analysis about the effect of vaccination on the level of meningococcal carriage and the incidence of meningococcal disease. The WHO’s position on the use of polysaccharide meningococcal vaccines in routine practice are also provided. In the conclusion the article presents the prospects for further use of polysaccharide vaccines to control the spread of meningococcal disease.

Background. The reactivity of cotton pulp during chemical processing is significantly lower compared to celluloses obtained from other cellulose-containing plants. Increasing the reactivity of cotton cellulose to chemical processing improves the quality of the resulting products based on it, as a result, labor productivity increases. Purpose. Replacing wood pulp imported from foreign countries with domestic cotton cellulose by increasing the reactivity of cotton cellulose to chemical processing, improving product quality and increasing the reaction rate. Methodology. In this work, we used methods for determining the composition and structure of cotton cellulose samples. The reactivity of the obtained samples to acetylation after treatment with electric charges was studied. An increase in reactivity was evaluated by a decrease in crystalline areas based on diffractograms that were recorded on a computer-controlled XRD-6100 apparatus (Shimadzu, Japan). Originality. A method is proposed for increasing the reactivity of cotton cellulose by treating it with high-voltage electric charges. Findings. The optimal voltage limits of 11-13 kV, the number of pulses 22-24, the capacitor capacitance of 0.6 µF were found, at which the maximum values of the reactive activity of cotton cellulose were achieved. [ABSTRACT FROM AUTHOR]

Background. Each molecule of a polymer substrate actually represents a whole spectrum of substrates (reaction centers) with different reactivity. The reactivity of polymers, which depends on many factors, including the presence of functional groups, is a collective concept, currently needs to be interpreted within the framework of the fundamental concepts of polymer physics and chemistry. This concept is a band gap in the electronic spectrum, representing the difference in the energies of the lowest free and highest occupied molecular orbitals of the polymer. Purpose. Discussion of the new concept of the quantum-chemical theory of the reactivity of polymers containing various functional groups on the example of the reactivity of N, O-carboxymethylchitosan in the preparation of nanoparticles. Methodology. Conductometric titration, NMR, IR spectroscopy, quantum chemical theory were used in the work. Originality, the question of the quantum-chemical theory of describing the reactivity of polymers containing different functional groups is considered by the example of obtaining Bombyx mori carboxymethylchitosan nanoparticles by precipitating coacervation (various substitutions both in oxygen at C6 (O-CMCh) and in nitrogen in C2 (N- CMCh). Findings. Nanoparticles of (O-, N-) carboxymethylchitosan of various sizes and shapes were obtained by the method of precipitating coacervation; a new concept for describing the reactivity of polymers was presented. It has been shown that the formation of nanoparticles implies an interaction between protonated amino groups and carboxyl anionic groups, with the formation of covalent and / or ionic bonds, which contributes to their stabilization. [ABSTRACT FROM AUTHOR]

The cohort pilot study had been done. Aim: to study the effectiveness of an antistress activation therapy on the functional state of human with the purpose of formation of adaptive reactions of activation and training high levels of reactivity among the two groups of patients with cardiovascular problems, ranks first among causes of death population: arterial hypertension (AH) and coronary heart disease (CHD). Material and methods. From the sub-sample of the Moscow population (396) were allocated to 2 groups of patients of 30 people in each (a control group and a group for anti-stress therapy for persons with hypertension and coronary artery disease that within 1 month took adaptogens (tincture of ginseng, Eleutherococcus, etc.) is minimized by a specially developed algorithm. For stress diagnosis international integrated questionnaire Perceived Stress (PSS); as well as Hospital Anxiety and Depression Scale (HADS) were used. Blood pressure, heart rate, body mass index, waist circumference were measured. In addition we used new methods "Antistress activation health improvement". Results. The average age in the intervention group was 59.4 years, and in the control group was 58.3 years, p>0.05. In compliance with results of the study has been marked that persons who were treated by methods "Antistress activation health improvement" sensed general and "internal" dumping, improving of duration and quality of sleeping. Irritability, level of stress, depression, and fatigability became rather less. Dynamics of emotions locked in psychometric scales showed distinct improvement of mood, decrease of fear, sorrow, anxiety, anger, emotional instability, increase of self-reliance, activity. Conclusion. The treatment of stress, anxiety, and depression must be complexes based on biological and psychological approaches.

The purpose of the study was to identify the relationship between the initial state of the organism and the result of the treatment of hypertrophic scars. 38 women of 16-35years of age were examined on the 5-7th days of the menstrual cycle, 16 of them had normotrophic scars and 22 - hypertrophic scars. The quality of scars, lipid profile, the concentration of thyrotropin, free fraction of thyroxine, growth hormone (GH), luteinizing and follicle stimulating hormone (FSH), cortisol, prolactin, estradiol, testosterone, progesterone, the concentration of TNF-a, lL-4, lL-6, lL-10, and the level of autoantibodies to DNA, lFN-a, lFN-y, b2-glycoprotein, Fc-fragments, collagen-2 were determined. Further on the laser treatment was performed: the scar surface was treated by multiple perforations under local anesthesia. Treatment outcome was assessed in 3 months by the clinical characteristics of the scar. lt was found that in 10 women hypertrophic scars reformed in normotrophic scars after the treatment, and 12 women still had hypertrophic scars. Patients with a positive result of treatment had a low concentration of GH (0.5 ± 0.1) and high concentrations of progesterone (6.0 ± 0.4) and FSH (6.7 ± 0.5 in the follicular phase of the cycle). The negative result of the treatment obtained in patients with significant shifts reactivity indicators: high atherogenic index (2.6 ± 0.2) and the level of GH (2.1 ± 0.5), low levels of cortisol (346.8 ± 39), testosterone (1.5 ± 0.2), lL-10 (3.89 ± 1.6) and antibodies to lFN-y (0.206 ± 0.05), lFN-a (0.385 ± 0.02), Fc-fragments (0.317± 0.04).

We studied axial motion of the stationary nuclear fission wave in the cylindrical core of the traveling wave reactor (known also as CANDLE) using an effective one-dimensional model of the fast spectrum reactor with uranium plutonium fuel. The model includes one-group diffusion equation for the neutron flux and kinetic equations for nuclear densities. The so-called velocity characteristic has been studied in our previous works. It is the dependence of the wave velocity on the effective concentration of the absorber. Due to instability of long-living 241Pu it has two branches, and the solutions of the lower branch are unstable. In this paper, reactivity was introduced into the diffusion equation as an additional parameter of the model, and the generalized equation of the velocity characteristic connecting the wave velocity with the effective concentration of the absorber and reactivity is obtained. Since the equation includes both parameters linearly and additively, their variations are interchangeable, in the appropriate scale. Obtained results open the way to study the velocity characteristic of the reactor with powerful reactor codes (outside one-group diffusion approximation), calculating the effective multiplication factor in the stationary wave mode for a series of fixed values of the reactor power.

The low reactivity of the respiratory system at low intensity and high responsiveness to the load of submaximal intensity detected in highly qualified athletes in the age range 22-46 years, coaching and aerobic endurance in athletes 17 to 26 years coaching and power performance. The high reactivity of the respiratory system at low load and reduced response to loading of submaximal intensity detected in highly skilled athletes 17-18 years coaching and aerobic endurance in athletes 40-46 years coaching power performance is that the former does not reduce the effectiveness of fan response. From elite athletes 40-46 years revealed a relative limitation of ventilatory response to submaximal activity, which is more pronounced in the representatives of power sports.

The existent approaches to proactive projects and programs management from the point of view of possibility of their usage while realization of projects and programs of development in agro-industrial complex are considered and systematized in the article. Comparison characteristics of usage peculiarities of proactive and reactive managements during the projects and programs realization life cycle are given. The analysis of models and methods worked out by leading scientists in the sphere of projects and programs management is carried out; the peculiarities of their usage are elucidated.

Evaluation of proliferative and IL-2-producing activity of peripheral blood lymphocytes wasperformed, using cultural methods, in patients with drug-sensitive and drug-resistant infiltrative pulmonary tuberculosis. The cell testing was performed at basal level and following in vitro stimulation with recombinant IL-2 and M. tuberculosis antigens. It was established that clinical course of infiltrative pulmonary tuberculosis, independently on drug sensitivity/resistance of the infectious pathogen, is accompanied by suppression of spontaneous lymphoproliferation. The levels of induced IL-2 production in drug-sensitive tuberculosis proved to be increased, whereas a reserve of IL-2-secreting reactivity of blood lymphocytes was lower than in drugresistant infection. Also, it was revealed that the level of lymphoproliferative response induced by IL-2, does not depend on clinical variant of tuberculosis, whereas stimulation of IL-2 production in blood lymphocytes is attained only in cases of drug-resistant tuberculosis variant.

Aim. To estimate the role of endogenous metabolic factors in formation of vascular endothelium reactivity in patients with different genesis cardiovascular regulation disorders.Materials and methods. The research included 30 patients with ischemic heart disease (IHD) with stable form of exertional angina (EA) of II–III severity class, 30 patients with I–II stage and 1st–2nd degree essential hypertension (EH), and 15 clinically healthy volunteers. We researched the signs of functional state of vascular endothelium before and after occlusion test. The parameters investigated included: adhesion of thrombocytes, spontaneous aggregation, prostacyclin activity of blood plasma, levels of antithrombine-III, of von Willebrand factor, contents of malonic aldehyde, of nitrites, of endothelin-1, of membrane-connected haemoglobin, of methaemoglobin in erythrocytes, activity of angiotensineconverting enzyme, level of sorption on the membrane of erythrocytes of nucleotides. Research of hemorheology was performed by viscosimetry method.Results. In healthy volunteers high probability of endothelium sensitivity to transverse strain decrease (in 82%) was determined and 25% increase of activity of peroxide oxidation of lipids. In patients with exertional angina influence of dynamic changes of blood flow on endothelium occurred by 2% decrease of viscosity and more than 120% increase of production von Willebrand factor (in 87%). It was concluded that as higher the production of prostacyclin in response to mechanic stimuli (more than 50%) is, the higher is probability of blood flow dynamic changes influence on endothelium. In patients with essential hypertension 30% increase of level of antithrombine-III in 100% of cases caused increase of sensibility of vascular endothelium to transverse strain.Conclusion. The most significant factors linked with sensibility of endothelium of vascular wall to dynamic blood flow changes in examined groups of patients were determined. In patients with exertional angina vascular reaction was mostly linked with rheological qualities and adhesive-aggregation characteristics of blood. In patients with essential hypertension the sensitivity of vascular endothelium was implied to be concordant with anticoagulant activity of blood plasma.

In this article the subcriticality determination of nuclear reactor is considered. Emphasized that, despite the requirements of regulatory documents on the subcriticality determination of VVER from the beginning of their operation, so far, this problem has not been solved. The results of subcriticality determination of Rossi-α method of the WWR-M is presented. The possibility of subcriticality determination of VVER is considered. The possibil-ity of subcriticality determination of Rossi-α method with time resolution is of about 100 microseconds is also considered. The possible reasons for the error in subcriticality determination of the reactor are indicated.

In the present work, we continue the study of the properties of edge dislocations in whiskers crystals of silver azide. The suggested arguments do not contradict experimental results, and are in favour of the assumption of the presence of the magnetic moment and electric charge line of the edge dislocation in silver azide. It is shown that the magnetic moment in crystals of silver azide is associated with silver ions, located along the lines of dislocation, which can be neutral, i.e. have a magnetic moment. To identify the edge dislocations the methods of powder figures and selective etchingwere used; to determine the magnetic moment, a methodology was developed based on direct measurement of the magnetic field B0 and the resulting field B, that arises in the process of samples magnetization.

This paper presents the results of experimental studies of education the vacancy cluster in threaded crystals of silver azide. It is experimentally shows the role of vacancy cluster in the reactivity of these materials. Methods of time management formation vacancy cluster are proposed.

Aim. To assess the levels of residual platelet reactivity (RPR) and its potential correction by antiaggregant therapy in patients with angina. Material and methods. The study included 40 patients with coronary heart disease (CHD), aged under 70 years, with adequate blood pressure control and no contraindications for antiaggregant therapy. All participants underwent general clinical examination, general blood assay, blood biochemistry, and platelet aggregation assessment (blind method). ADP (5 mkmol/l) was used as an aggregation inductor. The patients were randomised into two groups, to compare the antiaggregant activity of aspirin (thrombo ASS 100 mg) vs. plagril (clopidogrel 75 mg), and plavix (75 mg) vs. plagril (75 mg). Platelet aggregation was assessed at baseline and at least three weeks later. After three weeks of the initial therapy, the patients were switched to another therapy arm (cross-over). Finally, all patients were receiving two antiaggregants (thrombo ASS and plagril). Results. During the therapy with enteric coated aspirin (100 mg), RPR above the target level (>46%) was observed in 72,5%. After switching to clopidogrel therapy, target RPR levels were achieved in almost 50% (n=16). Among remaining resistant patients (n=13; 32,5%), 8 achieved target RPR while receiving a combination of aspirin and plagril. Therefore, only 5 patients (12,5%) were resistant to both medications. Clopidogrel monotherapy did not reduce RPR to target levels in 14 patients (35%). In this group, aspirin was effective only in one patient. Conclusion. High RPR levels were more prevalent during the treatment with enteric coated aspirin (72,5%), compared to clopidogrel therapy (plagril or plavix; 35%; p

The study was aimed at assessing the reactivity of cerebral vessels in patients with essential arterial hypertension (EAH) and different stages of blood pressure elevation. In 100 EAH patients, aged 30-60 years, cerebral blood flow parameters were assessed by transcranial Doppler ultrasound and capnometry at rest and during ventilation tests. The parameters of cerebral blood flow auto-regulation (CBFA) were calculated. The hemodynamic response to hyper- and hypoventilation was disturbed in 50 EAH patients (48,6%). Reduced blood vessel reactivity and functional CBFA reserve were explained by a decrease in vasodilatation reserve. The severity of CBFA disturbances positively correlated with EAH stage. The authors suggest that EAH stage could be a risk factor in the development of hemodynamic deficiency of cerebral blood flow.

A method was developed to study the initial palladium compounds (e.g. acetate or chloride) interaction with molecular hydrogen on a carrier surface. It is based on absorption of the corresponding acid evolved in the course of the reaction and its quantitative determination. A special apparatus was created enabling to study the kinetics of such reactions. The method allows investigating the metal centers formation on a heterogeneous catalyst surface.

For WWER-1000 operation at power level more than 75 % of nominal one (Nnом) in case of failure of safety important equipment, the direct activation of accelerated unit unloading (AUU) signal is initiated. This causes the designated control rod regulating group to be dropped into the core to rapidly depress the unit power for (~40 - 50) % of Nnом. When regulating group is dropped down, the negative reactivity is inserted into the core and subsequent transient takes place with power decreasing from initial power level to the new lower steady state one. For this transient the calculations of period and reactivity values are done for the beginning- and end-of-core-lifetime since both period and reactivity are the reactor safety important parameters. Additionally the WWER-1000 reactor power behavior is studied in time. As results of calculations shown for temperature reactivity coefficients, typical for the end-of-core-lifetime, the period value may be out of safety range and cause WWER-1000 scram. In the same time the calculation results of power and reactivity changes prove the WWER-1000 design operation conditions after AUU is activated and absence of scram initiation based on neutron-physical reactor parameters.

Objective. To study features of endothelium-dependent regulation of vascular tone in pts with systemic lupus erythematosus (SLE). Material and methods . 52 SLE pts aged 17 to 52 years (mean age 34±1,3 years) and 33 healthy volunteers of control group aged 22 to 50 years (mean age 32±2 years) were examined. Mean disease duration was 7,4+0,4 years. 4% of pts had acute, 27% - subacute, 69% - chronic course of the disease. 29% of pts had minimal, 50% - moderate and 21% - high activity. D. Celemajer ultrasonic method was used to assess endothelial function. Results. In healthy persons reactive hyperemia test showed increase of vascular lumen in systole and diastole so as decrease of relative systolic increase. SLE pts had increase of vascular wall rigidity, ultrasonic signs of brachial artery changes. Reactive hyperemia test at 15th second showed normal reaction of brachial artery in 38%, pathological - in 48% and indefinite - in 14% of pts. All pts with pathological reaction and only 40% of pts with normal reaction had renal disease.

The article shows the importance of reactive properties to realize the potential of canoeist of south-east Asia specializing in the 200 meters established on a specialized focus of the training process sprinter. The parameters of functionality of athletes based on integrated aerobic and anaerobic ensure competitive distance of 200 m. They are based on assessing level of aerobic power and capacity of energy supply and properties of the cardiorespiratory system in actively increasing metabolic acidosis.

Features of manifestation of special functional potential sportsmen a high class are presented. 15 sportsmen participated in research - members of a combined team of Ukraine. The test was used high-intensity 2 mines. Discrepancies of an individual reactivity of sportsmen are defned. They are expressed by parameters of reactions of an organism and serviceability of sportsmen in conditions of building up fatigue. It is exhibited, that typological discrepancies of a reactivity repute discrepancies of the contents and conditions of an intensifcation of training process during a macrocycle of sports preparation.

In this article the subcriticality determination of nuclear reactor is considered. Emphasized that, despite the requirements of regulatory documents on the subcriticality determination of VVER from the beginning of their operation, so far, this problem has not been solved. The results of subcriticality determination of Rossi-α method of the WWR-M is presented. The possibility of subcriticality determination of VVER is considered. The possibility of subcriticality determination of Rossi-α method with time resolution is of about 100 microseconds is also considered. The possible reasons for the error in subcriticality determination of the reactor are indicated. [ABSTRACT FROM AUTHOR]