Monthly Status Report, May 1951
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Biology and Medicine
of the new Committee on Radiation Studios was held at the National
Cancer Institute on May 13 with Dr. James 4. Sterner, Chairman, presiding.
(Or. Sterner is a Consultant to the Division).
Several proposals of
research projects in the general field of radiation studies including
one dealing with radiation effects on the neurophysiology of the monkey
were approved for support subject to joint approval by the National
Cancer Advisory Council.
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Operation Greenhouse
During tha third shot at Operation Greenhouse a modified Biomedical
Test Program was carried out with the remusining animals not used for
the principal Biomedical Test Program in the second ghot. Tha purpose
of this program wag to verify some of the results from the second shot
and to collect additional data on the efficiency of biological dosimeters.
Blological dosimetry values were determined by counting the various
kinds of chromosome breaks in the pollen mother cells af the plant,
Tradescantia, by measuring the loss in weight of the spleen and thymus
of mice after exposure, and wy determining the 1D 50 of mice. Dosimetry
values from these experiments are being compared with values obtained
by physical meagurements such as film badges.
Flash burn studies indicated that the time for maximum burn occurred
at about 0.3 of a secom after the initiation of the explosion.
At
present this is a tentative value, however it indicates that there is not
time to dodge behind a protection to minimize flash burning. The blast
wave, of course, travels much slower,
The LD 50 for neutron exposure with mice was investigated as well
as the LD 50 with gamma radiation on mica, doga, and swine. Autopsies
were performed on dogs ani swine, tissue samples werepreserved for
analysis in this country. The 3,100 surviving mice from Operation
Greenhouse have been returned to the Oak Ridge National Laboratory.
There
they wilt be kept for observations on the effect of the radiation on their
Livespan and for pathological changes such as development of cataracts
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SUES es
The principal scientific investigators concerned with the Blomadical
Program at Operation Greenhouse will devote the sumer to analysing their
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data at Los Alamos,
August 1.
Detailed results are scheduled for complstion by
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OFFICE >
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