[A possibility of using some pyrethroids to prevent plague in the Siberian natural foci of the souslik type].

Experiments have established that the pyrethroids deltamethrin and cypermethrin (decis and cimbush) may be used in the Siberian natural plague foci for not only emergency, but also early prevention of plague. This substantially expands and simplifies the possibility of organizing disinfection actions and reduces the cost of treatments. The findings are determined by the specific features of the biology and ecology of fleas inhabiting in the natural plague foci of the souslik type in a continental climate area. The specific features include the coincidence of preimago stages and the larger proportion of an adults to rodent nests; the low migration of imagoes from the inhabiting nests to the ground surface, only one insect generation that can develop within a comparatively short (4-5-month) warm period of a year.

[The growth movements of moss protonemata under clinostatic and microgravity conditions]. / Rostovye dvizheniia protonemy mkhov v usloviiakh klinostatirovaniia i mikrogravitatsii.

Populations of dark-grown protonemata of moss Ceratodon purpureus wt-4 (Germany) and wt-U (Ukraine) were rotated on clinostat or flown in space (experiment "Protonema" aboard Bion-11, December 24, 1996-January 7, 1997) to determine the effects of altered gravity on orientation of protonemata growing filaments. Protonemata had been cultivated 8 days in vertical stationary position at dark to be transported to microgravity or placed in clinostat for the period of 14 days. In the ground control, protonemata demonstrated the negatively gravitropic growth (straight upwards in a bundle of compact filaments). The horizontal or circular rotation in clinostat and exposure to microgravity made filaments grow every each way within the substrate plane but with an apparent trend to rightward curling resulting in "spiral galaxies".