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The present work is dedicated to study of the possibilities of improving the production method of 11C and 18F medical isotopes using a linear electron accelerator. Experimental studies of 11C and 18F isotopes production by the photonuclear technique were carried out in [1]. Various targets were irradiated by bremsstrahlung photons following by measurements targets’ activities. This experimental research has been carried out in the energy range from 10 to 40 MeV. The current work studies an angular distribution of bremsstrahlung photons in order to estimate the possibilities of producing maximum achievable levels of medical isotopes 18F and 11С activities. The angular distribution of bremsstrahlung photons is an important property of the irradiation stand which contains an assembly of targets. This important property allows designing necessary changes in the target assembly setup used to produce medical isotopes. The research presented in the current work was done as a computer simulation. The computer software package ‘KIPT’ was developed in С++ programming language, using the Geant4 toolkit in order to obtain the angular distribution of bremsstrahlung photons. Experimental setup materials as well as structural elements positions were defined in the DetectorConstruction class of our program. The parameters of an electron beam were defined in the PrimaryGeneratorAction class. The electron beam diameter was defined as 8 mm, energy Ее=36.7 MeV, corresponding to the real experiment carried out at the “Accelerator” Science and Research Establishment of Kharkiv Institute of Physics and Technology [1]. Models of physical processes occurring while the electron beam crosses the target assembly were defined in the PhysicsList class. All classes and modules necessary for the analysis of simulation results were included to our program together with visualization modules. Visualization modules use the OpenGL graphics library and the Qt5 software to represent the relative position of experimental setup parts and to visualize particle trajectories. As a result of this work, the angular distributions were obtained for the beam of electrons and bremsstrahlung photons directly before the target. This result will allow target assembly parameter optimization for optimal production of medical isotopes by the photonuclear technique.

Introduction: It is known that pesticides have both short-term and long-term effects of the action on the human body. Today, taking into account the growth rate of the agricultural crops protection means' market and the expansion of the range of pesticide mixtures and combined formulations, there is a need for a more in-depth study of its possible effects on the environment and the human body. Recently, a new fungicide containing a mixture of two active substances, benthiavalicarb isopropyl and folpet, was introduced for application in Ukraine. Considering the possible influence of both substances on the enzyme systems involved in the xenobiotic metabolism, potentiation of its carcinogenic action in the formulation can be expected. No genotoxic effect was revealed studying in vivo studies the mutagenic activity of both substances isolated. Therefore, both substances are epigenetic carcinogens with a promoter threshold mechanism of action. In this regard, the promoter action of these substances was studied by us in the mid-term test on a multi-organ model. The aim: The purpose of our work was an experimental study of the carcinogenic action of benthiavalicarb-isopropyl and folpet - substances with ascertained carcinogenic activity, under the conditions of its simultaneous influence on the organism of laboratory animals (rats and mice).Materials and methods: Toxicological, toxicometric (weight of animals, absolute, relative mass of internal organs) histological, microscopic, histochemical, and statistical methods were used in the study.Results and conclusions: No combined action of folpet and benthiavalicarb-isopropyl on the proliferation of carcinogen-transformed hepatocytes and the formation of hyperplastic nodules expressing γ-glutamyltranspeptidases (γ-GTP) as markers of pre-tumor changes in hepatocarcinogenesis was revealed. This allows us to conclude that there is no modifying effect of the folpet on carcinogenicity.