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Lifetime measurements have been performed for yrast rotational states of 100Zr and 104Mo using a 252Cf source in a differential plunger arrangement, together with the EUROBALL and SAPHIR multi-detector arrays. The system has been proved capable of covering a range of lifetimes from a nanosecond to a picosecond. The transition quadrupole moments are found to decrease by around 20% between I = 4 and I = 8 in the case of 104Mo while remaining constant in 100Zr. The origin of this effect lies either in a rotation-induced shape change, or in the strong mixing between the ground and s-bands in 104Mo.

The theory behind a new, three-dimensional analysis technique for the measurement of time-integral, perturbed angular correlation (IPAC) functions is presented. The new technique is described in relation to existing methods and in terms of its specific application to a large, Ge-detector array. The effective application of the new technique is demonstrated with results from an experiment where the g factors of excited states in 252Cf, secondary fission fragments were determined. A 252Cf source, sandwiched between two iron foils and placed in a saturated magnetic field at the centre of the Gammasphere detector array, was used to make IPAC measurements of prompt γ rays in order to deduce Larmor precession angles of stopped fragments in iron. The g factor of the Iπ = 2+ state in 104Mo was thus measured to be g = +0.248(22). This new measurement shows a factor-of-5 improvement to the precision which has previously been attained in more conventional experiments.

The $g$ factors of several low-lying excited states of the neutron-rich $^{101}\mathrm{Zr}$ and $^{103,105}\mathrm{Mo}$ nuclei have been measured for the first time. The isotopes were produced by the spontaneous fission of a $^{252}\mathrm{Cf}$ source, which was sandwiched between two magnetized iron foils and placed at the center of the Gammasphere spectrometer. The $g$ factors of excited states of fission fragments were inferred from Larmor precessions deduced from the measurement of time-integrated perturbed angular correlation functions. The magnitude and sign of the quantity $({g}_{K}\ensuremath{-}{g}_{R})/{Q}_{0}$ were determined from the mixing ratios measured for the 3/2[411] and 5/2[532] rotational bands in $^{101}\mathrm{Zr}$ and $^{103,105}\mathrm{Mo}$. The combination of this quantity with the measured $g$ factors permitted the separation of the particle-rotor parameters ${g}_{K}$ and ${g}_{R}$ for each band. The comparison of the extracted ${g}_{K}$ factors to Nilsson model predictions confirms current band assignments, and this agreement is consistent with an axially symmetric picture of these nuclei at low spins. The possible effect of triaxial deformation on the measured magnetic moments was investigated in the rigid triaxial rotor-plus-particle framework. The calculations suggest that triaxial deformation plays a stronger role in the Mo than in the Zr isotopes, but that triaxiality is likely to be dynamic. The extracted ${g}_{R}$ factors are consistently smaller than the $Z/A$ limit, in agreement with observations in neighboring even-even nuclei.

Lifetimes of excited states have been measured for the positive-parity rotational bands in neutron-rich Ba-142,Ba-144 as well as the 7(-) and 9(-) states of the negative-parity band in Ba-144 using the differential Doppler shift method. The deduced quadrupole moment, Q(t), of the positive-parity band decreases with angular momentum and overall shows good agreement with earlier measurements. The measured lifetimes of 7(-) and 9(-) states are used to determine the electric dipole moment, D-0=0.17(3) and 0.09(1) e fm, respectively, in the negative-parity octupole band of Ba-144.

The magnetic moments of I$^\pi = 2^+_1$ states in even–even A $\sim$ 100 fission fragments have been measured using the Gammasphere array, using the technique of time-integral perturbed angular correlations. The collective (core) g factors of several odd nuclei have also been determined. The data are interpreted within the context of the interacting boson model (IBA2).

To investigate the efficacy and safety of daily low-dose colloidal bismuth subcitrate in reducing duodenal ulcer relapse.Double-blind, double-dummy group comparative clinical trial with random allocation. Healing Phase: colloidal bismuth subcitrate 240 mg twice daily vs ranitidine 150 mg twice daily for up to 12 weeks. Maintenance Phase: nightly, colloidal bismuth subcitrate 120 mg vs ranitidine 150 mg vs placebo for up to 12 months (high-risk patients received active treatment only).clinical, endoscopy, random blood bismuth levels (and rapid urease test for Helicobacter pylori in a subgroup).194 with active duodenal ulcer.Cumulative healing at 12 weeks was 93% on colloidal bismuth subcitrate (of 92 patients) and 97% on ranitidine (of 102 patients). Relapse at 1 year was significantly less on active treatment as follows: placebo (50 patients) 60%; ranitidine (71 patients) 21%; colloidal bismuth subcitrate (64 patients) 33%. This was independent of the results of the rapid urease test which was positive in 78%, 88% and 76% of the patients respectively. Treatment was well tolerated. The highest median blood bismuth level (mcg/L) was 25 in the healing phase and fluctuated between 6 and 10 in the maintenance phase.Colloidal bismuth subcitrate, 120 mg nightly, is effective in reducing duodenal ulcer relapse and is well tolerated.

The magnetic moments of I π =2 1 + states in even–even A ∼100 fission fragments have been measured using the Gammasphere array, using the technique of time-integral perturbed angular correlations. The data are interpreted within the context of the interacting boson model (IBA2) leading to the suggestion of a strong νh 11/2 component in the deformed 2 1 + states of this region.

Myocardial perfusion in ten normal volunteers and 20 patients with coronary artery disease documented by recent coronary arteriography was studied with 99mTc-labeled SQ30217 and 201TI. Plantar 201TI imaging followed standard treadmill exercise and planar SQ30217 imaging followed upright bicycle exercise, performed to angina, or the same double product achieved on the treadmill test. Upright anterior, 30 degrees left anterior oblique, and 60 degrees left anterior oblique images were obtained for 3, 6, and 9 min, respectively, starting 2 min after injection of 15 mCi of 99mTc SQ30217. A second 15-mCi dose was injected at rest approximately 2 hr later, and the same imaging protocol was followed. No adverse reactions or laboratory abnormalities attributable to SQ30217 were observed. All scans on the normal volunteers were interpreted as normal. Qualitative readings of both tests were equally sensitive for detecting patients with coronary disease (SQ30217 - 16/20, TI - 17/20, p = NS) and identifying abnormal vessels (SQ30217 - 19/45, TI - 21/45, p = NS). Both agents were falsely positive in 1/15 vessels. Ten vascular regions showed persistent abnormalities on resting SQ30217 scans; eight of these were distal to stenoses of at least 90% and three were also abnormal on thallium redistribution images. Hepatic uptake of SQ30217 obscured inferoapical segments in some views in 14/20 patients but did not interfere with abnormal vessel identification.