Low prevalence of the ret/PTC3r1 rearrangement in a series of papillary thyroid carcinomas presenting in Belarus ten years post-Chernobyl

Many neurosurgeons prefer to use intraoperative computed tomographic (CT) scanning, when possible, to check whether there is residual lesion or unexpected bleeding. We report a practical intraoperative CT imaging system using a high-speed CT scanner installed in the operating room along with a digitally controlled neurosurgical operating table. We designed a rail-track system to mobilize the CT gantry. The gantry is fixed onto a motorized carrier that can be moved smoothly on a rail-track embedded in the floor and with a maximum reach of 2.85 m from the room's wall to the operating table. The longitudinal motion of the operating table is easily adjusted by a foot switch from manual control to automatic control directly from the CT scanner's computer like an ordinary CT scanner bed in increments of 2, 5 or 10 mm during CT scanning. Either a carbon-made radiolucent head frame or carbon-made head plate is used as a headrest. Using this CT scanner system, pre- and intraoperative CT scannings were performed on 46 patients with brain tumors, cervical lesions or other intracranial lesions. We could operate on the patient with enough working space between the mobile CT gantry and the operating table for microneurosurgery. We could obtain intraoperative CT imaging of a patient on the operating table while the surgical wound remained open, the surgical drapes kept in place, and the surgical position unchanged, saving time in intraoperative CT scanning and preparation for further surgery when needed. This intraoperative CT imaging system installed in the operating room should be useful for neurosurgery.     

Simulation of Foreign Trade Activity under Transition Economy Conditions

A system of mathematical models of foreign economic activity under transition economy conditions is considered. Input-output optimization models and econometric micromodels are the basis of this system. Simulation using real data and the mentioned models is performed. The obtained results allow us to explain some features of the structure of the Ukrainian export.     

Cycles in economic systems with open labor markets

A dynamic macromodel of an economic system with a monopsonic labor market and variable labor resources is considered. The initiation conditions for classical business cycles are investigated for this model. Bifurcation analysis of the model is performed to estimate the effect of the minimum wage on the way such cycles form. The results of theoretical analysis are supplemented with numerical experiments. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 48–72, July–August 2008.     

Heuristic methods for the analysis of a queuing system describing emergency medical service deployed along a highway

Consideration is given to a queueing model that describes the deployment of emergency medical service along a highway. Two heuristic methods are proposed for the approximate evaluation of stationary loss probability and utilization of ambulance cars. The high accuracy of these methods is demonstrated by several examples. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 84–99, May–June 2006.     

Hydrodynamic characteristics and efficiency of contact elements of wet-gas-cleaning equipment

Mathematical modeling, with the use of unidimensional equations, is employed as a basis for determining the relations between the hydrodynamic characteristics and the efficiency of wet-gas-cleaning in single-pass contact elements.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 5, pp. 733–737, November, 1985.     

Labor market modeling using a labor supply function of two-arguments

A two-argument function of individual labor supply is considered. Real wage and unemployment rates are the arguments of this function. Conditions of emergence of direct and inverse relations between these two economic indicators are investigated. This function is used to analyze processes in a competitive and monopsonic labor market. The expediency and conditions are substantiated for the use of the exogenous increase in labor remuneration by increasing minimal wage.