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The methods: Linear differential equations were used to formalize contemporary assumptions of self –sustaining tissue cell kinetics under the impact of adverse factors, on the formation and repairing of cell “pre-cancer” defects, on inheritance and retaining such defects in daughter cells which results in malignant neoplasms, on age-dependent impairment of human body’s function to eliminate such cells.The results: The model reproduces the well-known regularities of radiogenic cancer morbidity increase depending on instantaneous radiation exposure age and on attained age: the relative reduction at increased radiation age which the model attributes to age decrease of stem cells, relative reduction at increased time after radiation induced by “sorting out” of cells with “pre-cancer” defects, absolute increase with age proportional to natural cause mortality rate.The relevance of the developed quasi-biological model is displayed via comparison to the ICRP model for radiogenic increase of solid carcinomas’ morbidity after single radiation exposure. The latter model had been developed after Japanese cohort observations. For both genders high goodness-of-fit was achieved between the models at values of Gompertz’ law factor which had been defined for men and women in this cohort via selecting the value of the only free parameter indicating age-dependent exponential retardation of stem cells’ division.The conclusion: The proposed model suggests that the estimation of radiogenic risk inter-population transfer can be done on the basis of the data on age-dependent mortality intensity increase from all natural causes. The model also creates the premises for inter-species transfer of risk following the well-known parameters of cell populations’ kinetics in animal’s organs and tissues and Gompertz’s law parameters. This model is applicable also for analyses of age-dependent changes of background cancer morbidity.

Цель исследования - оценка качества жизни (КЖ) пациентов, оперированных по поводу церебральных аневризм (ЦА), выявление факторов, которые оказывают влияние на изменение качества жизни данной группы пациентов. Для оценки КЖ использован международный опросник SF-36, анкетирование проводилось через 2-12 мес. после операции. Исследовалась зависимость КЖ пациентов от пола, возраста, перенесенного кровоизлияния, состояния пациента в остром периоде кровоизлияния по шкале Hunt-Hess, варианта оперативного лечения и ближайших результатов лечения (по шкале исходов Глазго). Установлено, что качество жизни пациентов не зависит от варианта оперативного вмешательства, возраста пациента, зависит от пола пациента, от перенесенного кровоизлияния, коррелирует с результатами лечения по шкале исходов Глазго.

Aim. To reveal cognitive deficit after coronary artery bypass, the influence of citicoline, piribedil on the state of higher cerebral functions in the early and late periods after surgery.Material and methods. The study included 94 patients with ischemic heart disease. All patients were divided into 3 groups. Patients of the first group (n=30) were prescribed citicoline as a cerebral neuroprotective drug. Patients of the second group (n=32) had piribedil in addition to standard therapy. Patients of the control group (n=32) had only a standard treatment without any neuroprotective drugs. All patients underwent coronary artery bypass surgery. The cognitive function was assessed before, 10 days after and six months after coronary artery bypass.Results. Patients of group 1 and 2 had achieved pre-surgical levels of cognitive tests results 6 months after coronary artery bypass. The control group had achieved initial levels only in three tests: visual memory (immediate simulation; p=0.008), categorical association (p=0.002), clock drawing test (Wilcoxon test; p=0,005), while other indices were reduced in comparison with the initial ones.Conclusion. The obtained results allow considering the studied drugs as a protectors of cognitive function after surgery. Randomized controlled double-blind studies on large samples are needed to confirm these results.

Mathematical ratios were established according to the description of the calculation procedure for the values of the nominal risk coefficient given in the ICRP Recommendations 2007. It is shown that the lifetime radiogenic risk is a linear functional from the distribution of the dose in time with a multiplier descending with age. As a consequence, application of the nominal risk coefficient in the risk calculations is justified in the case when prolonged exposure is practically evenly distributed in time, and gives a significant deviation at a single exposure. When using the additive model of radiogenic risk proposed in the UNSCEAR Report 2006 for solid cancers, this factor is almost linearly decreasing with the age, which is convenient for its practical application.

To explain the known differences in the dose and age dependences of radiogenic mortality from leukemia and solid tumors after single exposure, a model was developed, which is a modification of the Kellerer-Rossi theory of dual radiation action. The model assumes formation in a cell of both single and double primary damages due to radiation and other carcinogens, while the recovery rate of single damages (φ) significantly exceeds that for double ones (ψ). Upon achieving a certain stage of the cell cycle (the critical age of cell – T), double damages become permanent and with probability of А can be inherited to daughter cells as “premalignant” defects. In contrast, in the Kellerer-Rossi theory, permanent damage is formed immediately after formation of the second damage at the next energy absorption event in the cell, i.e. ψ=0 .On the assumption that the premalignant defects only occur based on the double primary damages, i.e. φ>>ψ, the expressions for А were derived for the prompt radiation exposure and radiation exposure at a constant dose rate. They reproduce the effect increasing with decreasing of T, whereas the influence of T on the linear term of the dose expression in both cases is the same, but with decreasing of T the quadratic term increases faster for exposure at a constant dose rate than that for the prompt one. Thus, presence of the quadratic term in the dose expression for leukemia and its virtual complete absence for solid tumors may be due to lower T-value for hemopoietic stem cells. Predicted by the model dose rate influence on the quadratic term does not depend on the dose, so the reduction factor should be only applied to the quadratic term of the dose expression. This follows as well from the original version of the Kellerer-Rossi theory.

A mathematical model for radiogenic increasing of mortality was proposed, taking into account spontaneous background damages of the genetic material, that always occur in cells due to the influence of non-radiation internal and environmental factors. The model is based on the representation of indistinguishability between radiogenic andspontaneous cancers and on the postulates of the Kellerer-Rossi dual action theory. It was proposed that duringformation of premalignant damages dual interactions occur both between primary radiation damages, and betweenradiation and spontaneous primary damages (hybrid interactions). The role of the latter is particularly important at low levels exposure that corresponds to a linear dependence of cancer incidence on dose. Their significance is indicated by the following factor: at the adopted value of the nominal (radiation) risk factor (0,05 Sv-1) and cancer mortality share among the population (0,15–0,2), the contribution of non-radiative carcinogenic factors for the total life is equivalent to radiation dose of 3–4 Sv or radiation at a constant dose rate of 40–50 mSv / year.The model assumes formation in DNA of both spaced apart (single) damages with high probability of recovery, and nearby (double) damages, which are more likely to interact, entering into the permanent state. Permanent damages being formed in certain portions of DNA can be inherited to daughter cells as premalignant defects. The relative role of spontaneous primary damages is greater the more single damages are formed as compared to double ones within the area of potential interaction.It was shown within this model that the presence of background cancer mortality for initial and finite population in the used by ICRP expression for interpopulation risk transfer has logical and biophysical justifications. Accounting of spontaneous primary damages and hybrid interactions enhances the capabilities for development of radiation risk models.

The paper proposes a two-stage algorithm for autonomous relative motion determination of noncooperative and unknown object flying in space. The algorithm is based on image processing and can be applied to motion determination of space debris with unknown geometry and dynamic characteristics. The first stage of the algorithm is aimed at forming a database of possible reference points of the object during continuous observation. Tensor of inertia, initial velocity, and angular velocity of the object are also estimated. Then, these parameters are used in the second stage of the algorithm to determine the relative motion in real time. The algorithm is studied numerically and tested using the video of the Chibis-M microsatellite separation.

The chemical composition of the Soranovskii Miscanthus variety harvested in 2011 and 2012 was separately determined in the whole plant, leaves, and stem. In all cases, cellulose was found to prevail in the Miscanthus stem, and non-cellulosic components (the fat-wax fraction, ash, and lignin), in leaves. Cellulose samples were for the first time obtained from leaves and stems separately by two methods (nitric-acid and combined). The best quality cellulose was derived from stems. For instance, cellulose isolated from stems by the nitric-acid process was better than that from leaves, which was expressed as a higher α cellulose content (94,4 % versus 91,7 %) and polymerization degree (800 versus 580), as well as low weight fractions of non-cellulosic components: ash (0,07 % versus 1,01 %) and acid-insoluble lignin (0,45 % versus 1,51 %). The same tendency is observed in celluloses produced by the combined method: Cellulose from stems had better quality than that from leaves; specifically, it had a greater polymerization degree (1040 versus 640) and lower weight fractions of non-cellulosic components: ash (0,14 % versus 0,75 %), acid-insoluble lignin (0,88 % versus 4,2 %), and pentosans (6,8 % versus 8,53 %). It is obvious that cellulose obtained by the nitric-acid method can be suitable for chemical modifications, including nitration. Cellulose from the combined process can be utilized in paper industry.

Approaches to the process of vehicle research are described, research methods are presented, their advantages and disadvantages, and the important role of mathematical research is noted. The points of differences between operator control and automatic control systems are considered. A mathematical model of the operator’s actions in driving a vehicle is described, which reflects the psychophysical properties of the operator, the presence of absolute and differential thresholds of sensitivity. The model takes into account the delay in the operator’s response and the discreteness of information perception. The model can be used for modeling all software management tasks. Moreover, when forming the control action of the operator - in the mathematical model, the characteristic features of the operator’s activity that differ from an automatic control system are considered, and when forming the control action of the operator - in the mathematical model, some conditions were applied, thanks to which, it is possible to calculate the necessary deviation of the controls, such as the steering wheel and, accordingly, the wheels of the vehicle, knowing the required nature of changes in the parameters of the traffic’s vehicle.

Оценены результаты лечения пациентов со множественными аневризмами в остром периоде субарахноидального кровоизлияния. Тяжесть состояния пациентов при поступлении оценивалась по шкале Hunt - Hess, результаты лечения - по шкале исходов Глазго. Установлено, что выключение из кровотока всех имеющихся у пациента аневризм в остром периоде кровоизлияния при их хирургической доступности не ухудшает состояние пациента. Исход заболевания в большей степени зависит от тяжести состояния пациента перед операцией, а не от количества прооперированных аневризм.

The paper considers the initial stage of organization and development of the first State control organ of the independent Belarus – Control Chamber of the Republic of Belarus on the basis of scientific grounds of control theory of economic systems. Scientific and methodologically considered organizational and coordination approaches to the activity of the Control Chamber have promoted to higher intensity and efficiency of financial and economic control in the initial period of the activity of new control organ and the activity of all control organs of the Republic has taken systemized and perfectly oriented character. Such approaches have made it possible to stabilize macro-economic situation in the Republic and strengthen its economic security. The Control Chamber through highly-qualified personal, created and practically introduced methodological principles of control activity, international cooperation experience and finally high efficiency of practical control activity has made its historical contribution in formation of fundamentals of the State Control in Belarus.13th of March 1992 is the day when the Law “About Control Chamber of the Republic of Belarus” has been enacted by the Supreme Council of the Republic of Belarus and this day is to considered as the Day of State Control foundation in the Republic of Belarus.

The Research Objective: Comparative assessment of informational content of various techniques, respiratory tests for Helicobacteriosis detection. Methods et methods: Research of existence of H.pylori in stomach has been conducted by respiratory tests in 106 patients with various diseases of stomach and duodenum. All researches have been conducted on an outpatient basis. Esophagogastroduodenoscopy with mucous biopsy and determination of H.pylori in biopsy materials have been followed by respiratory tests. Respiratory tests 13C UBT and 14C UBT have been carried out. The comparative analysis of respiratory tests for Helicobacteriosis detection has been performed. Results: The conducted researches have showed that, the respiratory tests are favourable for H.pylori diagnostics. They are methodically simple and short-term. Conclusion: Results of comparative researches showed that ammoniac respiratory tests for Helicobacteriosis detection in stomach possess lesser sensitivity than the 13C UBT — respiratory test and may be used for the primary diagnostics which results demand carrying out additional methods of diagnostics. Low specificity of these techniques and inauthentic results do not control the efficiency of eradication of H.pylori and do not present any value in medical examination of the population.