[en] The aim of this paper was comparison of diagnostic preciseness of scintimammography (SM) using of ⁹⁹MTc-MIBI with dynamic magnetic resonance (DMR). With the SM and DMR 280 patients were examined from which 70 patients histopathologically were examined. For SM sensitivity (80%), specificity (91%), positive prediction value (83%) and negative prediction value (89%) and for DMR sensitivity (68%), specificity (80%), positive prediction value (65%) and negative prediction value (82%) were obtained. SM in the differential diagnostic of breast lesions plays more important role as DMR

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[en] The basic requirements for the geological situation at a deep underground radioactive waste disposal site are highlighted, a survey of candidate host sites worldwide is presented, and the situation in the Czech Republic is analyzed. A 'General Project of Geological Activities Related to the Development of a Deep Underground Disposal Site for Radioactive Wastes and Spent Fuel in the Czech Republic' has been developed by the Nuclear Research Institute and approved and financed by the authorities. The Project encompasses the following stages: (i) preliminary study and research; (ii) examination of the seismicity, neotectonics, and geodynamics; (iii) search and critical assessment of archived geological information; (iv) non-destructive survey; and (v) destructive survey. The Project should take about 30 years and its scope will be updated from time to time. (P.A.)

[en] The VR-1 training reactor is a light water reactor of the pool type using enriched uranium as the fuel. The moderator is demineralized light water, which also serves as the neutron reflector, biological shielding, and coolant. Heat evolved during the fission process is removed by natural convection. The reactor is used in the education of students in the field of reactor and neutron physics, dosimetry, nuclear safety, and instrumentation and control systems for nuclear facilities. Although primarily intended for students in various branches of technology (power engineering, nuclear engineering, physical engineering), this specialized facility is also used by students of faculties educating future natural scientists and teachers. Typical tasks trained at the VR-1 reactor include: measurement of delayed neutrons; examination of the effect of various materials on the reactivity of the reactor; measurement of the neutron flux density by various procedures; measurement of reactivity by various procedures; calibration of reactor control rods by various procedures; approaching the critical state; investigation of nuclear reactor dynamics; start-up, control and operation of a nuclear reactor; and investigation of the effect of a simulated nucleate boil on reactivity. In addition to the education of university-level students, training courses are also organized for specialists in the Czech nuclear programme

[en] In addition to the production of short-lived radioisotopes, the Slovak Cyclotron Laboratory is also engaged in the application of neutron capture therapy, radiotherapy with fast neutrons, and proton therapy. Experiments were carried out where the operating quantities and conversion factors between the neutron fluence and the spatial or personal dose equivalent were determined by Bonner spectrometry over the entire range of energies used, employing a set of moderators. To obtain the requisite dosimetric parameters of the (n,γ) radiation fields, the deconvolution process (statistical regularization) was modified into a rather simple procedure, tractable by using a conventional PC AT. Calibration measurements were employed to obtain the dependence of the sensitivity of albedo dosemeters on the neutron dose ratios in two positions of the dosemeter (on the front and rear sides)

[en] The trajectories of ions were investigated in the approximation of a static, spatially periodical field along with the magnetic field. Statistical examination of the particle set in a potential so high that the stochastic nature of the trajectories plays a role shows that the mean value of the square of the distance from the starting point of the particles increases linearly with time. This property suggests that the motion is diffuse in nature

[en] The microtron is described. Electrons can be extracted from the accelerating compartment from the 12th or 24th track with variable energies from 6 to 24 MeV with a step of 0.5 or 1 MeV. The electrons extracted are monoenergetic electrons with energy dispersion in the order of tens of keV. The microtron incorporates electron guides with electron optics elements which enable the electron beam to be extracted with the desired aperture and divergence to 3 workplaces where they are led into air through vacuum-tight aluminium windows. The first workplace is employed to test the production of ¹²³I by a photonuclear reaction with ¹²⁴Xe in bremsstrahlung beams on electron accelerators, to the optimization of this production, and to the development of instrumentation for the irradiation of high-pressure xenon gas targets. The second workplace includes a facility making it possible to create very homogeneous high-energy gamma and electron fields with a precisely determined dose rate (gamma field: up to 5 Gy/min, electron field: up to hundreds of Gy/min; size of the standard field: 10 x 10 cm²). The facility was adapted to enable the properties of PbWO₄ scintillation single crystals to be investigated. The homogeneous bremsstrahlung field size was increased to 17 x 17 cm², and a special thermostat with Peltier cells was constructed. The third workplace is equipped with a source of photoneutrons obtained by (γ,n) and (γ,f) photonuclear reactions on suitable converters. This source gives intense mixed gamma and neutron fields for the study of radiative damage and radiation resistance of semiconductor materials, components and circuits