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Gamma rays of energy 9.404 and 9.700 MeV were obtained from the reaction22Ne(p, γ)23Na at proton energies of 640 and 950 keV respectively and were resonantly absorbed in sodium metal. Isotopically separated22Ne targets on nickel backings were used. The following level widths for23Na were obtained: The 9.404 MeV level: Γ=65 ±40eV Γγ=2.2±0.7eV. The 9.700 MeV level: Γ=9.5−1.0+4.5 eVΓγ=5.6−0.8+1.2 eV. The disagreement between the results for the 9.404 MeV level and the previously determined values can probably be ascribed to proton scattering in the window of the gas target used in the latter measurement.

The gamma decay of the22Ne(p, y)23Na resonances in the proton energy rangeEp=1.0→2.0 MeV has been investigated with a 20cm3Ge(Li) detector. Implanted targets were used. The absolute strengths of the strongest resonances were determined and the branching ratios of twenty resonance levels and several bound states are reported. Mean lifetimes of the levels atEx=2.078 MeV (18.7±3.5 fs), 2.393 MeV (580−190+370fs), 2.641 MeV (88−14+20fs), 2.985 MeV (4.0−1.0+1.3fs), 3.679 MeV (24−4+5fs), 3.915 MeV (7.4−2.0+2.5fs) and 4.775 MeV (<2.0 fs) were obtained from measurements of the gamma ray Doppler shifts.

The lifetime of the fourth excited state of45Sc, at an energy of 720 keV, was determined in a nuclear resonant scattering experiment. Gamma rays of the desired energy for the excitation of this level were obtained by Compton scattering of the 1173 and 1332 keV photons from a 4300 Ci radioactive60Co source. A value of (5.6±1.2) meV was found for the radiation width of the level, assuming a value of 5/2 for its spin. The corresponding mean lifetime is (0.12-0.02+0.04) ps. An attempt was made to determine the spin of the level by means of angular distribution measurements.

The yield curve and resonance strengths of resonances in the24Mg(p, γ)25Al reaction for the proton energy rangeEp=800 keV toEp=1,830 keV, have been determined and the existence of a resonance atEp=1.184 MeV confirmed. Single energy spectra as well as decay schemes and branching ratios are given for these resonances. An upper level of 2.0×10−15sec for the lifetime of the 3.079 MeV level in25Al results from a Doppler shift attenuation measurement carried out on the 2.624 MeV gamma line originating in the 3.070 MeV→0.455 MeV transition in25Al.

The time course and signal-transduction requirements for proto-oncogene c-jun expression in T-cells were investigated. Expression of c-jun mRNA was evident at 30 min after stimulation. Both the activation of Ca2+/phospholipid-dependent kinase as well as an increased intracellular free Ca2+ concentration were necessary for the maximal induction of c-jun mRNA and synthesis of Jun protein 1 h after stimulation.