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Biomedical subjects

D Cohen

Publications and source records attributed to D Cohen.

At least 793 records · Page 44Linked to original sources
PubMed1969

On population growth in a randomly varying environment.

If a population is growing in a randomly varying environment, such that the finite rate of increase per generation is a random variable with no serial autocorrelation, the logarithm of population size at any time t is normally distributed. Even though the expectation of population size may grow infinitely large with time, the probability of extinction may approach unity, owing to the difference between the geometric and arithmetic mean growth rates.

Ecology↗
PubMed1968

Magnetoencephalography: evidence of magnetic fields produced by alpha-rhythm currents.

Weak alternating magnetic fields outside the human scalp, produced by alpha-rhythm currents, are demonstrated. Subject ard magnetic detector were housed in a multilayer magnetically shielded chamber. Background magnetic noise was reduced by signal-averaging. The fields near the scalp are about 1 x 10(-9) gauss (peak to peak). A course distribution shows left-right symmetry for the particular averaging technique used here.

Brain↗