Czechoslovak Academy of Sciences

About: Czechoslovak Academy of Sciences is a based out in . It is known for research contribution in the topics: Catalysis & Adsorption. The organization has 13227 authors who have published 17335 publications receiving 272882 citations.

Standardization of the earthquake magnitude scale

Abstract: Предлагается стандартизация шкалы магнитуд на основе следующих принципов: а) магнитуда для всех типов волн определяется на основании формулы (1); б) при определении магнитуд применяются стандартные калибровочные функции σ(Δ); в) средное значение магнитуды для одного землетрясения определается для каждого типа волн отдельно, комбинация этих значений не рекомендуется.

Cyclic stress-strain response of polycrystalline copper in a wide range of plastic strain amplitudes

Abstract: Polycrystalline copper was cyclically strained with constant plastic strain amplitude from a very wide interval (3×10 −6 −1×10 −2 ). Fatigue hardeing-softening curves and the plot of the loop shape parameter vs. the number of cycles were evaluated. Fatigue softening observed in low amplitude cycling was studied in detail. Measurements of the loop shape parameter which indicated the cyclic slip localization were accompanied by surface relief observations and electronmicroscope observations of the dislocation structure. Several mechanisms of the fatigue softening were considered. The basic cyclic stress-strain curve was evaluated and the difference between this curve and curves using apparent saturation values of the stress amplitude were discussed.

“Unidentified” Mobile Protozoans from the Blood of Carp and Some Unsolved Problems of Myxosporean Life Cycles

Abstract: Heavy infections with enigmatic mobile organisms have recently been found in the blood of carp (Cyprinus carpio) in Central Europe. The organisms measure up to 15 μm, are variable in shape, and exhibit an unceasing twitching or dancing movement. Their developmental cycle starts with a primary cell enclosing a secondary cell. The former grows while the latter produces inside itself by a series of binary fissions and internal cleavages up to eight secondary cells, each of which encloses an inner (tertiary) cell of its own. In addition, up to four tiny cells with compact nuclei (“residual bodies”) also result from divisions of the secondary cells. Primary cells containing the products of the division of secondary cells finally disintegrate, releasing the secondary cells, which in their turn become new primary cells and repeat the cycle all over again. The structure and behavior of these organisms were so incompatible with existing ideas on myxosporean development that their myxosporean affinity was at first unrecognized. The final proof of their identity–appearance of myxosporean spores in sterile, experimentally infected hosts–is still to be presented. The interpretation of the myxosporean features of their life cycle (i.e., [1] the pericyte nature of the primary cell, [2] proliferation by disintegration of the pseudoplasmodial primary cell, [3] no rigidly fixed pattern in vegetative development), their ultrastructure (i.e., [1] characteristic bundles of microtubules and numerous free ribosomes in secondary cells, [2] lack of centrioles, [3] membranes enclosing the secondary cells within the primary cells), and facts on their epizootiology (i.e., [1] no success at transmission via leeches, [2] the occurrence of these organisms along with Sphaerospora renicola Dykova and Lom) suggest that they are stages of S. renicola from the kidney of carp. Similar mobile organisms were found in the blood of fry of two other fishes (Gobio gobi and Tinca tinca) which are also hosts for a Sphaerospora that infects the kidney. This suggests that these organisms represent an early phase in the developmental cycle in the genus Sphaerospora. The existence of cells enveloped one within the other (secondary and tertiary cells) in the developmental cycle, a characteristic myxosporean feature itself, is an intriguing parallel to similarly enclosed cells in sporogenesis of Paramyxea (Ascetospora).

On the theory of heat-conducting micropolar fluids with microtemperatures

Abstract: Microthermopolar fluids are introduced as a subclass of microthermofluids. In this subclass micromotion consists of rigid rotation only. The local balance laws and the linear constitutive equations are extracted from the theory of microthermofluids. Restriction regarding the material coefficients appearing in the constitutive equations are deduced by thermodynamical considerations. The problem of Poiseuille flow between two parallel plates is solved.