Blazar spectral variability as explained by a twisted inhomogeneous jet.

Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles, with possible intervention of shock waves or turbulence. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events and can also explain specific properties of blazar emission, such as intra-day variability, quasi-periodicity and the delay of radio flux variations relative to optical changes. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions-such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution-can explain snapshots of the spectral behaviour of blazars in many cases. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities or rotation of the twisted jet cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016-2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing angle. The agreement between observations and theoretical predictions can be seen as further validation of the relativistic beaming theory.

[Psychological characteristics of working and non-working elderly people.]

A comparative analysis of the psychological characteristics of the working and non-working population in the context of personal employment, demand and quality life. The study was conducted with the participation of 51 women and 58 men, age 65,35±5,25 years. Randomization into two groups: the 1st group - 59 people of those continuing to work in the field of higher and vocational education; the 2nd group (50 people) consisted of non-working pensioners whose labor activity was related to teaching, taking care of their families, children and grandchildren, the circle of their social contacts is limited by the connections necessary to ensure life. An assessment was made of the orientation of the personality, the level of prevailing needs, the formation and strength of motives, the degree of adequacy of one's own attitude to various life situations, and the psycho-emotional state. It is shown that working pensioners have a higher indicator of the personality's orientation to the task and a low indicator of the personality's orientation to oneself. In the 1st group a stable psycho-emotional state was revealed for a number of functional indicators of a physical, role, social nature, significantly higher indicators of vitality and the physical component of health, they strive to maintain professionalism, financial freedom, and independence. In the 2nd group the desire to overcome social isolation, the desire to develop creativity in oneself prevails. In the 1st and 2nd groups, there were no differences in the levels of the motivational-need sphere. To expand the possibilities of the life potential of an elderly person, it is necessary to study the psychological characteristics older working and non-working population.

[The assessment of risk factors of development of extra body mass in children of school age].

The global problems of children health include overweight and obesity and associated high risks of disability, premature death and complications of mental health in adult age. Purpose of the study is to identify alimentary and social risk factors of development of extra body mass in children and adolescents 7-17 years old residing in industrial center of the Eastern Siberia. The average age of studied group of children was 10.95 years. The sampling survey and anthropometric examination of children of school-age was carried out with participation of their parents (legal representatives). The results were evaluated by parametric statistical methods. The analysis testifies predominantly fat-based dietary model in children with normal and extra body weight. It is established that diet of children is inadequate in fish, curds, cultured milk food, meat, vegetables, fruits and drinking water. And 51,67-61,90% of children never consumed seafood. The most significant factors associated with extra body mass and obesity in children and adolescents were status of working mother and her specialized secondary education, high body mass index of father, satisfactory family income, high body mass index of mother. The results of study can be useful for correcting and elaborating further strategies of development of healthy diet in institutions of general education.

[Risk assessment for public health associated with nitrate content in crop products].

The increasing need of the population for crop products (СP) makes continuous monitoring of nitrate content an increasingly urgent task. The accumulation of multidirectional data on the effect of nitrates on the state of the body requires further studies to assess the alimentary risk caused by their admission to the population of various regions. The aim of the work was to study the levels of nitrate contamination of CP and assess the associated risk to the health of children and adults in the Baikal Region. Material and methods. The characteristics of СP contamination with nitrates were given according to the results of socio-hygienic monitoring for 2015-2019. The exposure to nitrates was estimated according to the data of their chronic daily intake with RP. Reference exposure levels were used to calculate hazard quotients for different age groups of the population. Results. The average number of annual studies in the Republic of Buryatia was 1000.6 [95% confidence interval (CI) 887.4-1113.8], the proportion of СP with nitrate content in concentrations above the permissible level was observed on average with a frequency of 4.51% (95% CI 4.11-4.91), which was 3.6 fold higher than the Russian average for 2019 - 1.26%. The alimentary effect of nitrates on the adult population of the Republic of Buryatia, due to admission from СP, was estimated as permissible at the level of the average centile trend, and as unfavorable at the level of the 90th centile. In children, nitrate exposure lead to an unacceptable risk at the level of the average centile tendency of the content of the contaminant in СP, which exceeded 1.0. A comparative analysis of СP safety indicators revealed the priority of nitrate pollution in a number of areas of the Republic of Buryatia. The high levels of СP nitrate contamination are primarily caused by the entrance of local products to the consumer market of the Republic of Buryatia. Conclusion. Taken together, the current situation poses a certain health risk and necessitates further in-depth study of the causes and factors of nitrate contamination. To reduce health risk assessment uncertainties, it is necessary to update data on СP consumption levels among different population groups, including preschool and infant children.

[Features of actual nutrition of the adult population in Republic of Buryatia in modern conditions].

Evaluation of the actual nutrition of the population of individual regions allows the development of targeted practical measures to improve nutrition, the structure of food consumption and appropriate recommendations to ensure optimal development and health status of a person. In order to study the nutrition of the adult population of the Republic of Buryatia, a retrospective analysis of the feeding structure data was conducted according to the data of the territorial department of the Federal State Statistics Service for the Republic of Buryatia, and the results obtained in the course of the questionnaire survey of 426 people (chosen by selective method with observance of representativeness) were analyzed. The data are presented obtained on the results of comparison with physiological needs in energy and nutrients for men and women in the most employable age of 30-39 years, having the third group of labor intensity. The structure of the food indicates its irrationality, which was confirmed by an increase in the consumption of food products with high content of saturated fats and added sugars, a decrease in the consumption of biologically valuable food products with high food density. In the product mix of the adult population of the republic, both among men and women, there was a lack of consumption of products from aquatic bioresources, vegetables, dairy products and eggs. At the same time, the consumption of bakery, flour-grinding products and potatoes in aggregate amounted to 120% of the recommended level. According to the results of the observation, 91.6% of the interviewed did not take into account the distribution of caloric intake by meals, in 50.8% the highest calorie intake was for dinner. Actual nutrition included elements that are risk factors for the development of endocrine pathology, disorders of the hormonal system and other metabolic diseases. There was a high level of energy intake for a number of years, which averaged 2891±43.6 kcal in men, 2407±38.4 in women, due to excess of fat and carbohydrates with a protein content of 82.4-87.3% of the recommended level. As a result, the problem of healthy nutrition, bringing the diet in line with the real physiological needs of a person requires serious systemic decisions in terms of organizing, systematizing and standardizing nutrition.

[REGIONAL INDICES OF TRACE ELEMENT LEVELS IN HAIR IN CHLILDREN OF THE POPULATION OF THE IRKUTSK REGION].

747 hair samples of the pre-school aged children from different regions of the Irkutsk Region have been analyzed with the aim to establish the regional reference indices. The measurements were performed by the atomic-absorption method. The population deficiency of the essential microelements of zinc, copper along with the simultaneous excess of magnesium, mercury was revealed to be observed at the territory of the Irkutsk Region. According to the results of the study of mercury level in biological medias of the children population of the Irkutsk region it is possible to mark the unfavorable areas where chronic anthropogenic load has led to the accumulation of mercury in the body.

[Individual risks to adolescent health, caused by contaminating the air, and their relationship with the levels of specific autoantibodies].

The high levels of the air pollution create prerequisites for the development of the pathology of target organs exposed to chemical agents. Big enterprises of oil refining and chemical industry of the Irkutsk region are located in the cities of Angarsk and Sayansk. The average level of the air pollution for several years in these cities is assessed as high and moderate, respectively. The use of the personalized approach may allow to more correctly evaluate the risk for the damage to health and the body's response to external impacts. The purpose of this study was to assess the risk offormation ofpathological processes in the body of adolescents in the conditions of inhalation exposure to chemicals, taking into account the individual load and study of the level of specific autoantibodies. The study included 373 adolescents from the city with high levels of air pollution and 188 schoolchildren from the city with a moderate level pollution. There was made an evaluation of the individual chemical hazard load on adolescents ' body due to the air pollution, physiologicalfeatures and the organization of educational process and leisure. There were studied the levels of specific autoantibodies, reflecting the state of the organs - targets for the impact ofpollutants. The calculation of the individual chemical load allows to calculate indices of the hazard for the health problems of each individual and to identify individuals at increased risk of developing diseases of organs and systems, which are targets for exposure to pollutants. The increase in the hazard index of developing respiratory diseases was found to be accompanied by an increase of the relative content of autoantibodies against membrane antigens of the lung tissue. There was revealed the elevation in autoantibodies levels to the proteins of vascular endothelial with increasing hazard index of disturbances in the cardiovascular system in adolescents living in city with high levels of air pollution.

[Hygienic estimation of the nutrition and the risk of morbidity associated with its violation].

Among risk factors possessing a main importance in the shaping of theA public health the leading place is featured to the rational nutrition. Presented results testify to the absence of stable group in the adult population of Irkutsk who eats regularly, with a rational multiplicity and having all essential meal reception and the recommended food package. There was revealed the role of nutrition in shaping of morbidity rate in the adult population. The risk of circulatory diseases was established to account of 2.5 (95% CI 2.1-3.6), the infectious and parasitic diseases - 2.4 (95% CI 1.7-3.5), the endocrine system - 2,2 (95% CI 1.4-3.4), and urinary system - 2.3 (95% CI 1.7 to 3.0).

[Hygienic assessment of the overwroughtness of educational activity in schoolchildren of 5-10 classes of secondary schools].

The state of health in children and adolescents during the time of education in secondary schools is getting worse: the prevalence rate of functional disorders and chronic diseases is increasing. There was executed the assessment of the overwroughtness of the training-education process in secondary school institutions. The prior characteristics of the educational activity are: intellectual, sensory, emotional loads; their monotony and mode of educational activity, school work intensity. The system of indices of the overwroughtness of the education labour was formed with account ofpsycho-physiological characteristics of children's organism. There was performed the research of the overwroughtness of educational activity in 820 schoolchildren. The overwroughtness of the educational process was evaluated on the basis of chronometry research, questionnaire survey of teachers and parents, and with taking into account the organization of educational process. In questionnaire survey there were involved 52 teachers and 389 parents. The assessment of overwroughtness factors of the educational activity was carried out in 5-10th classes for academic disciplines: Russian Language, Literature, Mathematics, History, Geography, Foreign Languages. It was found that the characteristics of "mental load" in schoolchildren are established to be the one of the main limiting factors that allow to refer training activities to "overwroughted of first degree" (3.1 class). Sensory loads on the studied academic subjects are rated as the second class of overwroughtness and are "permissible." The monotony of loads was revealed to correspond to 1st and 2nd class of overwroughtness and is therefore an optimal or acceptable. Training activities in the traditional educational institution corresponds to the 2nd class of overwroughtness - "permissible." The arduousness of the educational process in an innovative school is rated as the third class of the first degree ofthe overwroughtness (3.1). According to results of the study of the arduousness of the educational labor the study of mathematics in grades 5-9 on indices of the mental load was noted to correspond to the 1st degree of arduous activity (3.1 class). The acceptable level of the arduousness of the training and educational labour in nearly all classes was established in the Russian language, Literature, History and Geography, Foreign language. High school students are established to be exposed to effects of emotional load more than mid-level students. There are developed proposals on the optimization of the learning process, allowing to reduce the level of intellectual, sensory, emotional load.

[Thyroid gland pathology in children population exposed to the combination of iodine deficiency and fluoride pollution of environment].

The article presents results of study of the impact of iodine deficiency and technogenic fluoride on the state of the thyroid gland in children. On the example of two districts of the city of Bratsk there were executed dynamic investigations (2002 and 2012), including the estimation of the pollution of ambient air and soil by fluorine compounds, levels of iodine intake by the body, the clinical examination of children aged from 5 to 7 years d and interviewing of their parents. In the course of the medical examination there were executed: physical examination by the pediatrician, endocrinologist, ultrasound examination of the thyroid gland, the determination both of serum hormone content by radioimmunoassay and urinary excretion offluorine and iodine. Concentrations of hydrogen fluoride and a solidfluorides in ambient air led to the accumulation offluoride ion in the soil. The iodine entering with drinking water and food, was established to provide only 37.5-50% of the daily requirement of iodine. Increased fluoride ion content in urine and milk teeth in children is associated with the concentrations of the fluorine-containing pollutants in the ambient air and soil. The fluoride pollution against the background of the natural iodine deficiency was established to increase the frequency of functional and morphological disorders of the thyroid gland in children.

[Assessment of carcinogenic risks to workers of the main enterprises of the Irkutsk region].

The purpose of research is the assessment of the individual cancer risk (ICR) for workers of the basic occupations in key branches of industry of the Irkutsk region. There was executed the calculation of ICR levels for workers of the basic occupations of the aircraft industry, aluminum smelters and vinyl chloride production plants. The estimation of the exposure for workers was carried out according to long-term time-weighted average concentrations in the air of the working area, for the population - on annual average concentrations in the ambient air. To assess the risk that is not associated with the profession, the dose was calculated for the period of life (70 years). When calculating the toxicant doses in the working area there were used the "standard" indices ofpulmonary ventilation for adults, body weight, the work experience in the contact with carcinogens of 30 years, the number of days in the contact of 240, the duration of the working time 8 or 12 hours (in accordance with the working hours) duration. ICR for the Irkutsk population amounted of 3.08E-04, in Shelekhov - 4.8E-05, Sayansk - 1.1E-05. The amount of risk depends on the content offormaldehyde in all territories and chromium VI in cities of Irkutsk and Shelekhov. ICR for workers of basic occupations of studied plants in dozens of times are higher than for the urban population. Priority carcinogens are: chromium VI, nickel, formaldehyde, silicon dioxide -for the aircraft plant employees; 1,2-dichloretan, vinyl chloride - for the workers of vinyl chloride production plant; benzopyrene - for the aluminum smelter workers.

[Changes in Cerebral Blood Flow and Cognitive Function in Patients Undergoing Coronary Bypass Surgery With Cardiopulmonary Bypass].

PURPOSE: to study effect of coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) on regional cerebral blood flow and cognitive function in patients with ischemic heart disease (IHD). MATERIAL AND METHODS: We included into this study 22 patients with IHD subjected to CABG surgery with CPB. All patients underwent brain SPECT scanning and comprehensive neuropsychological testing 1 day before, 10-14 days and 6 months after surgery. RESULTS: Overall CABG with CPB was followed by reduction of regional cerebral blood flow relative to baseline in frontal and parietal cortex (p < 0.01). Substantial reduction (> 5%) of cerebral perfusion in early postoperative period was observed in 15 patients (68%) while seven patients (32%) had no significant changes of regional cerebral blood flow. Changes of cerebral perfusion correlated with dynamics of cognitive status. Mean measures of immediate verbal memory, delayed memory, and learning decreased after surgery by 25.6 (p = 0.002), 43.3 (p = 0.000003), and 23.1% (p = 0.00000), respectively. Moreover after CABG with CPB patients demonstrated slowing of psychomotor speed by 13.6% (p = 0.03). CONCLUSION: CABG with CPB was associated with reduction of cerebral perfusion leading to cognitive dysfunction. Immediate and delayed verbal and visual memory, learning and psychomotor speed were most sensitive to the negative effects of surgery.

[Changes in Cerebral Blood Flow and Cognitive Function in Patients Undergoing Coronary Bypass Surgery With Cardiopulmonary Bypass].

PURPOSE: to study effect of coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) on regional cerebral blood flow and cognitive function in patients with ischemic heart disease (IHD). MATERIAL AND METHODS: We included into this study 22 patients with IHD subjected to CABG surgery with CPB. All patients underwent brain SPECT scanning and comprehensive neuropsychological testing 1 day before, 10-14 days and 6 months after surgery. RESULTS: Overall CABG with CPB was followed by reduction of regional cerebral blood flow relative to baseline in frontal and parietal cortex (<0.01). Substantial reduction (>5%) of cerebral perfusion in early postoperative period was observed in 15 patients (68%) while seven patients (32%) had no significant changes of regional cerebral blood flow. Changes of cerebral perfusion correlated with dynamics of cognitive status. Mean measures of immediate verbal memory, delayed memory, and learning decreased after surgery by 25.6 (p=0.002), 43.3 (p=0.000003), and 23.1% (p=0.00000), respectively. Moreover after CABG with CPB patients demonstrated slowing of psychomotor speed by 13.6% (p=0.03). CONCLUSION: CABG with CPB was associated with reduction of cerebral perfusion leading to cognitive dysfunction. Immediate and delayed verbal and visual memory, learning and psychomotor speed were most sensitive to the negative effects of surgery.

[Features of psychophysiological status in adolescents with different intensity of sporting hours].

The experimental study of psychophysiological parameters of the central nervous system (CNS) has been performed in the adolescents who combine the learning-educational and sporting activities. The differences in psychophysiological indices in dependence on the intensity level of sporting loads have been revealed in the trained and non-trained adolescents in the presence of similar genetically determined abilities which may be determined by the force of the nervous system. The psychophysiological profile of.the youths and girls with a high intensity of sporting loads is characterized by the balance of nervous processes, the optimal functional state of CNS. The significantly higher speed of visual-motor reaction were revealed to be in the person with a high intensity of sporting loads than in moderate and low intensity of sporting loads. The psychophysiological profile in the adolescents with a low and moderate intensity of sporting loads in differed by disbalance of nervous processes with prevalence of the braking processes, a low speed of visual-motor reaction as the functional state of CNS is characterized by the pathological declinations. The attention level was found to reach the average values in the teenagers examined independently of intensity of sporting loads.

[ASSESSMENT OF THE QUALITY OF DRINKING WATER AND RISK FOR THE POPULATION'S HEALTH IN RURAL TERRITORIES IN THE IRKUTSK REGION].

The hygienic analysis of centralized and decentralized water supply in rural population in Irkutsk region was performed. About 403 thousand of the upstaters use water wells, voids and springs. In drinking water there were detected significant concentrations of iron, nitrates, manganese. On the base of the application of risk assessment methodology there was calculated noncarcinogenic risk for adults (HI = 1.2-1.3) and children (HI = 1.1-2.9). Carcinogenic risk for water from groundwater sources supply is 1.56 · 10(-5)-2.1 · 10(-4) for 22.2 thousand of upstaters. There were determined priority carcinogenic ingredients: arsenic (contribution is 56.3-100%) and hexad chromium (contribution is 29.9-35.8%).

[The informativeness of indices of the heart rate variability for the identification of the adverse effects of environmental factors on the health of adolescent girls].

There was performed an investigation of informativeness of indices of the heart rate variability at rest and during orthostatic testing in the adolescent girls residing in the industrial town and in the village. The influence of unfa- vorable environmental factors was established to be reflected by the indices of the spectral analysis and cardioin- tervalography. In urban girls there was noted the marked increase of the centralization of heart rhythm control on the background of the increased activity of the sympathetic compartment and the reduction of the influence of the parasympathetic compartment of the autonomous nervous system on the sinus node. In rural adolescent girls the func- tional state of the autonomic nervous system being the optimal is characterized by an adequate response to the active orthostatic test of the parasympathetic and sympathetic compartments with the moderate involvement of mechanisms of the central control of the cardiac rhythm. Results of the study have an important significance for the diagnosis of the early disorders of health in adolescent girls.

[THE LEVELS OF SPECIFIC AUTOANTIBODIES AND RISKS FOR THE FORMATION OF PATHOLOGICAL PROCESSES IN CONDITIONS OF INHALATION EXPOSURE TO CHEMICALS].

The exposure of atmospheric pollutants on the organism may be a precondition for the development of pathological processes in organs and system to which they have tropicity. The change in the levels of specific autoantibodies occur long before the clinical manifestation of the disease. The aim of the study was the investigation of relationships between the levels of specific autoantibodies and risks of the formation of pathological processes of organs and systems in conditions of the inhalation exposure to chemicals. There was made an assessment of levels of the air pollution and indoor air in the industrial centers of Eastern Siberia. There were calculated indices of danger from the inhalation exposure of chemical compounds and the risks for the development of the pathology of organs and systems. There was studied the relative content of specific autoantibodies to the organs and systems that are at high risk of the development ofpathological processes. The highest overall risks for the development of respiratory diseases, immune system and cardiovascular system were established in schoolchildren residing in areas of high and medium levels of air pollution. In general, the identified changes in the content of specific autoantibodies characterizing the state of the major organs and systems ofchildren residing in areas of high riskfor the development of pathological processes associated with the content of chemical compounds in the air cannot be properly interpreted as the realized risk of environmental impacts and require further study.

[RISK ASSESSMENT TO HEALTH OF THE POPULATION OF BURIATIIA IN CONNECTION WITH THE CONSUMPTION OF FOODSTUFF].

Evaluation of the risk associated with contamination of food products coming to the population of the Republic of Buryatia, was performed on the basis of data on the content of contaminants in basic food products and results of the questionnaire survey of the adult population. There are considered groups with taking into account gender differences and dietary preferences. Hazard index of chemical impact of non-carcinogenic substances coming from the food, in the surveyed individuals with predominance of lipid-protein diet is on the border of the permissible level (HI = 1,06-1,18). There are most probable effects of negative impact of toxicants with a significant proportion of the diet of imported products: in females--on the endocrine system (HI = 1.27-2.83), central (HI = 1.35) and the autonomic nervous system (HI = 1.29); in males--on the endocrine system (HI = 2.7). Carcinogenic risks are in the second range (more than 1 case per 10,000 people), the main contribution (62.2-78.9%) into the number of additional cases of malignant tumors among the population of the Republic of Buryatia is made by cadmium.

[Evaluation of health risk for adult urban population, considering contribution of occupational exposure].

The authors studied potential and actual health risks for adult population of Shelekhov town. Production of aluminium and crystalline silicon is characterized by high general toxicity and increased risk of respiratory and immune disorders. Health risk for industrial workers is 2 times higher than that for general population.

[Results of biomonitoring for zinc in children of the Irkutsk region].

The aim of the work is to test the application of the method of evaluating the content of zinc in the hair of the child population for solving SHM tasks on the example of the Irkutsk region. In total 426 children aged 5-6 years were examined, selected in four groups. The first group was consisted of children residing in a large industrial center to the south of the region, the second--in the the small town of the central part, the third group was formed by rural children of the central region, and the fourth--the northern and foothill regions. Hair analysis was performed by atomic absorption method. Found that zinc content in hair was established to be prone to significant variability. In children of the southern industrial center of the region (Group 1) there was noted the least amount of zinc (median is of 65.6 mg/kg). In 53% of the samples the element content was below the absolute norm (AN), out of which 25% below the biologically permissible limits (BPL). Only in 8.5% of the samples the zinc content exceeded AN and 3%-- BPL. In the range of AN there are 38% of the children, within the BPL range--71%. In the 2nd, the median of the concentration of zinc in the hair was 152.5 mg/kg. In the range of the AN there were 53% of the samples, in the BPL range--86% of the samples. Deviations from the reference levels were observed in the direction of exceedence of values. 36% of rural children (group 3) are provided with zinc within the limits of AN, 93%--within BPL. Only in 6% of children the zinc content in the hair below AN or BPL. In the 4th Group only 7.7% of samples were in the AN range and 27% of the samples--in the BPL range. 92% of the samples were way beyond the limits of AN and 73%--beyond the BPL. In most of the samples the higher content of zinc was observed. The highest concentrations of zinc in hair were observed in children living in the northern foothills and the Irkutsk region, which are characterized by elevated levels of this metal in the soil. In the diet of the inhabitants of these regions there is prevailed local food of animal origin, which is the main source of the entry of zinc into the body. In areas of intensive industrial development, despite the rather high zinc content in the objects of the environment, there was noted the high frequency of the zinc deficiency states, especially in conditions of complex chemical factors exposure and lifestyle that may be associated with features of not only input, but also the absorption of zinc in the body children.