[en] The hit theory of the mechanism of biological radiation effects in the cell is discussed with respect to radiotherapy. The mechanisms of biological effects and of intracellular recovery, the cumulative radiation effect and the cumulative biological effect in fractionated irradiation are described. The benefit is shown of consistent application of mathematical and physical models in radiobiology and radiotherapy. (J.P.)

No abstract available

No abstract available

[en] The principle of MHD generators is briefly described and their history and main development problems indicated including especially combustion chambers, MHD channels, electrodes, and magnets. The first generation of MHD generators is briefly reviewed and the specifications of the most interesting parameters are compared. Some data are also shown on the first combined magnetohydrodynamic unit of an overall electric output of 500 MW being built in Ryazanh. (B.S.)

[en] In 1981, the first proton-antiproton collisions were carried out at maximum energy of 270 GeV in the Super Proton Synchrotron in CERN. Technical modifications made it possible to achieve beams with sufficient energy and sufficiently monochromatic, with luminosity of 10³⁰ particles/cm² needed for the production of heavy intermediate bosons W⁺, W^- and Z⁰. Methods of detecting intermediate bosons are discussed on the basis of their decay into e⁺, e^-, μ⁺, μ^- and neutrinos. The collected experimental material was computed, every recorded interaction was spatially reconstructed on the basis of curvatures of paths of prodUced particles detected in giant detectors UA1 and UA2. Of the total number of one thousand million proton-antiproton collisions five cases were selected such which may be interpreted as the production of heavy boson W with a mass of 81+-5 GeV/c². (M.D.)

[en] Current state and prospects are outlined of controlled fusion reaction, including a brief description of tokamak devices. Further developments in thermonuclear energy production and problems of containing thermonuclear energy and converting it to electric power are indicated. (L.O.)

[en] Although a conception of exceedingly great importance, thermonuclear synthesis is not anymore as popular as it used to be some time ago. The reasons for this are discussed, and the problems, issues and challenges of this branch of science and technology are highlighted with emphasis on ITER - the International Thermonuclear Experimental Reactor. The article was written in relation to the forthcoming Prague conference on plasma physics and nuclear synthesis. (P.A.)

[en] A brief history is shown of nuclear weapon development, i.e., of the atom, hydrogen and neutron bombs. The physical principles are explained of the neutron weapon and possible methods are indicated of its manufacture. The effects of neutron bomb radiation are discussed with regard to military aspects. (B.S.)

[en] The use of gamma and fast electron radiations for food preservation is described. Examples are given of the application of ionizing radiation for retarding potato germination, onion growth, and fruit ripening, for limiting the action of microorganisms, and removing salmonella from meat products. The method has remarkable prospects although it may not be considered to be a general-purpose method. Geographic and economic conditions should always be taken into consideration. (J.P.)

[en] It is very difficult to assess the effect of artificial ionizing radiation sources on health of mankind because this contribution usually is but a fraction of the radiation intensity from natural sources to which mankind has been exposed in the course of its whole evolution. In addition, the natural background dose rate strongly depends on the composition of the Earth's crust in a given locality and its altitude above sea level. In Czechoslovakia the dose rate values range within two orders. Even under the assumption that the number of nuclear installations will maximally increase, their contribution by the year 200O will have still been a fraction of burden from natural sources. (Ha)