RESUMO
Several biological objects were flown in Cosmos 782 in order to investigate the effects of HZE cosmic particles and other environmental factors of space. Space flight results in chromosomic aberrations in lettuce seeds, decreased germination rate and increased frequency of abnormalities in tobacco seeds and decreased developmental capacity in Artemia eggs. In lettuce and tobacco seedlings, changes were observed not only in seeds hit by heavy ions but also in nonhit seeds. The results indicate that exposure to the space environment can induce important changes in biological objects and emphasize the usefulness of investigations carried out on organisms less complex than mammals.
Assuntos
Radiação Cósmica , Sementes/efeitos da radiação , Voo Espacial , Ausência de Peso , Zigoto/efeitos da radiação , Animais , Artemia/crescimento & desenvolvimento , Artemia/efeitos da radiação , Aberrações Cromossômicas , Meio Ambiente Extraterreno , Germinação/efeitos da radiação , Íons Pesados , Larva , Lactuca/crescimento & desenvolvimento , Lactuca/efeitos da radiação , Mitose/efeitos da radiação , Sementes/crescimento & desenvolvimento , Nicotiana/crescimento & desenvolvimento , Nicotiana/efeitos da radiaçãoRESUMO
The aim of the Biobloc experiment is to determine the biological effects of cosmic rays. Biobloc is a stack made up of biological layers and physical detectors (nuclear emulsions and plastic). Artemia eggs and tobacco seeds are used by French workers. Irradiation by cosmic heavy ions induces a late developmental inhibition of Artemia eggs. A light increase of emergence rate is observed for the non-hit eggs. The results are compared with those of previous space experiments. Investigations on tobacco seeds are in progress.
Assuntos
Artemia/efeitos da radiação , Radiação Cósmica , Nicotiana/efeitos da radiação , Voo Espacial , Ausência de Peso , Zigoto/efeitos da radiação , Animais , Artemia/crescimento & desenvolvimento , Íons Pesados , Larva/crescimento & desenvolvimento , Larva/efeitos da radiação , Monitoramento de Radiação/instrumentação , Sementes/efeitos da radiação , Nicotiana/crescimento & desenvolvimento , Zigoto/crescimento & desenvolvimentoRESUMO
Artemia salina dry eggs exhibit a great resistance to different physical factors: acceleration and vibration, low temperature, high vacuum and magnetic fields. Vibration test, alone or combined with acceleration test decreases the Artemia salina egg developmental capacity. Nevertheless, the differences are small and much lower than those observed in previous space experiments. The viability of Artemia eggs is not impaired by low temperature, high vacuum exposure and by high magnetic fields (15, 25 and 150 Koersted) or by earth magnetic field shielding.
Assuntos
Aceleração , Pressão Atmosférica , Crustáceos/embriologia , Campos Eletromagnéticos , Fenômenos Eletromagnéticos , Óvulo/fisiologia , Temperatura , Vibração , Animais , FemininoRESUMO
Paramecia cultures placed at 3800 meter altitude, show a proliferating activity acceleration if we compared them to control cultures placed at low altitude under the same environment conditions. These results confirm the cosmic irradiation influence upon the activating effect produced by the natural ionizing radiations on living organisms.
Assuntos
Divisão Celular/efeitos da radiação , Radiação Cósmica , Paramecium/efeitos da radiação , Efeitos da Radiação , Altitude , Animais , PressãoRESUMO
We have used Artemia salina eggs, embedded in polyvinyl alcohol, to study the biological effects of heavy ions of cosmic rays. Each biological layer was sandwiched between track detectors. Hit eggs by heavy ions show a great inhibition of their developmental ability. A lower inhibition is observed for eggs that were flown but not hit. Simulation experiments are in progress to determine the factors responsible for inhibition of eggs that were not hit and to improve our knowledge of cellular damage induced by heavy ions.