PTV margin for dose escalated radiation therapy of prostate cancer with daily on-line realignment using internal fiducial markers: Monte Carlo approach and dose population histogram (DPH) analysis.

Using internal fiducial markers and electronic portal imaging (EPID) to realign patients has been shown to significantly reduce positioning uncertainties in prostate radiation treatment. This creates the possibility of decreasing the planning target volume (PTV) margin added on the clinical target volume (CTV), which in turn may allow for dose escalation. We compared the outcome of two plans: 70Gy/35fx, 10 mm PTV margin without patient realignment (Reference Plan) vs. 78Gy/39fx, 5 mm PTV margin with patient realignment (Escalated Plan). Four-field-oblique (gantry angles 35 degrees, 90 degrees, 270 degrees, 176 degrees, 325 degrees) beam arrangement was used. Monte Carlo code was used to simulate the daily organ motion. Dose to each organ was calculated. Tumour control probability (TCP) and the effective dose to critical organ (Deff) were calculated using the biologically normalized dose-volume histograms. By comparing the biological factors, we found that the prescription dose can be escalated to 78Gy/39fx with a 5 mm PTV margin when using internal fiducial markers and EPID. Based on the available dose-response data for intermediate risk prostate patients, this will result in a 20% increase of local control and significantly reduced rectal complications provided that less serial dose-volume behaviour of rectum is proven

The coupling between the solar wind and proton fluxes at GEO

The relationship between the solar wind and the proton flux at geosynchronous Earth orbit (GEO) is investigated using the error reduction ratio (ERR) analysis. The ERR analysis is able to search for the most appropriate inputs that control the evolution of the system. This approach is a black box method and is able to derive a mathematical model of a system from input-output data. This method is used to analyse eight energy ranges of the proton flux at GEO from 80 keV to 14.5 MeV. The inputs to the algorithm were solar wind velocity, density and pressure; the Dst index; the solar energetic proton (SEP) flux; and a function of the interplanetary magnetic field (IMF) tangential magnitude and clock angle. The results show that for lowest five energy channels (80 to 800 keV) the GEO proton fluxes are controlled by the solar wind velocity with a lag of two to three days. However, above 350 keV, the SEP fluxes, accounts for a significant portion of the GEO proton flux variance. For the highest three energy channels (0.74 to 14.5 MeV), the SEPs account for the majority of the ERR. The results also show an anisotropy of protons with gyrocenters inside GEO and outside GEO, where the protons inside GEO are controlled partly by the Dst index and also an IMF-clock angle function. © 2013 Author(s)

Determination of the functional status of vestibular apparatus at children aged 5-6 years old.

The physiological methods of determination of the functional state of vestibular analyzer are considered. The indexes of systole and diastole pressure, frequencies of heart-throbs, are chosen. Methods were used before and after standard vestibular irritation. Research was conducted on the base of child's preschool establishment. In it took part 120 children in age 5 - 6 years. Insufficient development of vestibular analyzer is set for children. Selected exercise for the improvement of spatial orientation and statodynamic stability

BECKER’S ECONOMIC THEORY IN THE GENESIS OF THE INSTITUTE OF ECONOMIC POWER IN MODERN UKRAINE

The article analyzes problems of power in general and economic power in particular, appeared on the background of extreme conditions of the development of social relations in modern Ukraine, caused by radical transformation of social and state institutions. The author tried to consider the distribution of power authorities between main influence groups under conditions of globalization from the point of view of G.S. Becker’s theory, who stated that “… the economic approach provides maximizing behavior in more expressed form and wider approach, than other ones…” According to the author, the use of the economic approach at analyzing the genesis of the power institute in modern Ukraine is universal, because it is based on main economic paradigms of human behavior – acceptable, wholesale, imputed, shade and so on prices; repeated and reiterated, important and insignificant decisions; emotionally loaded and neutral aims; behavior of nouveaux riches, ill, medics, businessmen and workers, professors and students, law-abiding citizens and criminals. The application area of the economic approach, understood in such a way, is so wide that it includes the subject of economic science. The importance of studying power problems grows, when the researcher addresses to the concrete society, in which on the background on general processes of globalization, build-up of tendencies of openness of national economies, typical for the whole European civilization, radical changes of social and state institutions take place, and as a result extreme conditions of social development and human existence appear. Ukraine found itself in such conditions in last years, so it causes a necessity to consider possibilities of the effective distribution of power between main economic agents under conditions of global economy from new positions. Problems of the Ukrainian state also actualize the analysis of the mechanism of economic power to the great extent, in particular, in concerns the economic decay, complete dependence of Ukraine on external markets and influences, collapse of the “two-vector” policy, declared by the Ukrainian authorities during the years of independence – this all gives grounds for rethinking the role of power in the open economic system, which part is the native economy