Biomedical subjects

R Demets

Publications and source records attributed to R Demets.

3 recordsLinked to original sources

PubMed2000

ESA payloads and experiments on the Foton-12 mission.

The international Foton-12 mission in September 1999 was a milestone in terms of payload mass, complexity and scientific diversity. ESA's contribution amounted to an unprecedented 240 kg--almost half of Foton's total payload. The Agency's 11 experiments covered fluid physics, biology, radiation dosimetry, materials science and meteoritics. This article describes the mission from an ESA perspective and highlights the initial results.

Equipment Design↗

PubMed1986

Cellular Interactions during the Mating Process in Chlamydomonas eugametos.

A method to determine the mating competence of Chlamydomonas eugametos was developed. The contribution of each mating type in the pair formation was investigated using asymmetric gamete mixtures. It was established that pair formation is not mediated by a pheromonal attraction mechanism between partner gametes, but depends on collision chances. On the other hand, it was demonstrated that during transient contacts between partner gametes the flagellar agglutinability of both partners is stimulated, evidently to prepare a successful mating. The plus mating type was generally less agglutinable than the minus mating type and was a rate-limiting factor in the mating process.

Journal Article↗

PubMed1979

Length growth of two Escherichia coli B/r substrains.

Length growth of synchronized Escherichia coli B/r substrain A (ATCC 12407) and B/r substrain F26 (Thy his) was followed with an electron microscope. Cells were grown with doubling times (tau) of 60 min (B/rA) and of 82 and 165 min (B/rF26). Different length growth patterns were found for the two substrains. In B/rF, the length growth rate increased about midway in the cell cycle. For tau = 165 min, the rate increase was preceded by a short period of slow growth. For B/r A (r = 60 min), this period seemed to occur at the beginning of the cell cycle. The possibility is raised that the different length growth patterns are related to different deoxyribonucleic acid replication patterns of the respective strains.

Cell Cycle↗