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Lewis, J.

Publications and source records attributed to Lewis, J..

22 records · Page 2

Emergency-vehicle VHF antenna

Helical VHF antenna mounts on roof of moving vehicle to communicate with distant stations via earth satellites. Antenna requires no pointing and can provide two-way communication while vehicle moves at high speed. Device has proved extremely successful in electrocardiogram transmission tests between medical services vehicle and hospital emergency room.

Anderson, R. E.

Limitations to growth of microorganisms on Uranus, Neptune, and Titan

Reappraisal of the probabilistic policy toward planetary contamination by terrestrial microorganisms carried aboard space probes is suggested on the grounds that assignment of numerical probabilities to qualitatively unknown phenomena, as expressed in Phillips's (1974) formulation of the probability of contamination, is inappropriate. As an alternative, it is proposed that fundamental knowledge of the interacting nature of life on earth, interrelations between terrestrial organisms, and continuing effects of these organisms on earth's atmosphere and surface should guide the formulation of a sounder scientific quarantine policy. Simple conservative atmospheric models most favorable for life on Uranus and Neptune are examined. It is concluded that terrestrial microorganisms will not grow on either planet due to limitations of liquid water, atmospheric convection to lethal depths, the absence of energy sources and nutrients, the presence of ammonia and hydrogen, insufficient concentrations of biologically necessary ions, and the lack of a surface. The likelihood of terrestrial microorganism growth on Titan is found to be vanishingly small.

Margulis, L.