Quadrupole Deformation of Barium Isotopes

The B(E2:0_1^+ -> 2_1^+) values of the Ba isotopes (Z=56) exhibit a sharp increase in deformation as the neutron numbers approach the mid-shell value of N=66. This behavior is anomalous because the 2_1^+ level energies are very similar to those of the neighboring isotopes. By means of the axially-symmetric deformed Woods-Saxon (WS) hamiltonian plus the BCS method, we investigated the systematics of B(E2) of the Ba isotopes. We showed that 15% of the B(E2) values at N=66 was due to the level crossing, occurring at the deformation with beta being nearly 0.3, between the proton orbits originating from the orbits Omega=1/2^-(h11/2) and 9/2^+(g9/2) at zero deformation. The latter of these two was an intruder orbit originating from below the energy gap at Z=50, rising higher in energy with the deformation and intruding the Z=50-82 shell. These two orbits have the largest magnitude of the quadrupole moment with a different sign among the orbits near and below the Fermi surface. Occupancy and non-occupancy of these orbits by protons thus affect B(E2:0_1^+ -> 2_1^+) significantly.Comment: 10 pages, 2 figures, to be published in Phys.Lett.

Effects of exposure to cigarette smoke on intestinal propulsion in rats.

The effects of acute exposure to cigarette smoke and systemic administration of nicotine on intestinal propulsion were investigated in rats. The propulsive activity was measured as migration of charcoal powder in the intestine. This activity was suppressed by acute exposure (10 min) to cigarette smoke and by nicotine (0.5 mg/kg x 2, s.c.) administration. This intestinal suppression was more marked in the rats given nicotine than in those exposed to cigarette smoke, whereas the plasma concentrations of nicotine in both rats were similar. These results suggest that acute exposure to cigarette smoke and nicotine administration delay gastric emptying and/or suppress intestinal propulsion, and that some components other than nicotine contained in cigarette smoke may attenuate the suppression of intestinal propulsion induced by nicotine.</p

Pharmacokinetic Evaluation of Omeprazole Suspension Following Oral Administration in Rats: Effect of Neutralization of Gastric Acid

In order to evaluate a clinical use of omeprazole suspension, we examined the pharmacokinetics of omeprazole after oral administration in rats. Although the administration of omeprazole suspension buffered by NaHCO3 solution did not produce a significant increase in the area under the concentration-time curve (AUC) value compared with non-buffered group, the administration of NaHCO3 buffer immediately after dosing of omeprazole suspension buffered by NaHCO3 caused a significant increase in the AUC value. These results suggest that the NaHCO3 treatment following the administration of omeprazole buffered suspension effectively decreased the degradation of the compound by gastric acid. Therefore, the successive administration of NaHCO3 solution after the omeprazole dosing seems to be a simple and useful method for the administration to patients who cannot receive tablets.</p