In high precision Coulomb excitation experiments & particles of 10.0, 10.5, and 10.6 MeV and i60 ions of 42.0 and 46.0 MeV were used to excite the first 2+ states in i'2'ii+iis'i20'i22'i2~Sn. Static quadrupole moments Q(2+) and reduced quadrupole transition. probabilities B(E2;0 2+) were extracted from intensities of particles elastically and inelastically scattered at angles near 173' into an annular detector. The values of Q(2') are very small and consistent with 0.0 b. These results are in agreement with theoretical predictions based on pairing plus quadrupole forces.

Seven axenic wild-type and repair-deficient mutant strains of the cellular slime mold Dicryusrelium discoideum have been treated with the furocoumarin 8-methoxypsoralen (8-MOP) up to 50 pgirne and then exposed to near ultraviolet light (UVA 320-400 nm) up to 21 kJlm2. Fluence-response survival curves exhibit shoulders at lower fluences and an exponential lethal response at higher fluences. Neither the psoralen alone nor the irradiation alone produced any measurable lethal effect. Wild-type strains, which show resistance to 254 nm UV and gamma radiation, also show resistance to psoralen plus UVA. The moderate sensitivity of a rad D repair-deficient mutant strain and the extreme sensitivity of a rad B mutant strain to 8-MOP plus UVA parallel their responses to UV and gamma radiation. However a rad C mutant which is sensitive to UV, exhibits wild-type response to photoactivated psoralen.

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