Nuclear pairing and Coriolis effects in proton emitters

We introduce a Hartree-Fock-Bogoliubov mean-field approach to treat the problem of proton emission from a deformed nucleus. By substituting a rigid rotor in a particle-rotor-model with a mean-field we obtain a better description of experimental data in $^{141}$Ho. The approach also elucidates the softening of kinematic coupling between particle and collective rotation, the Coriolis attenuation problem.Comment: 2 pages, 1 figur

Decay Rate of Triaxially-Deformed Proton Emitters

The decay rate of a triaxially-deformed proton emitter is calculated in a particle-rotor model, which is based on a deformed Woods-Saxon potential and includes a deformed spin-orbit interaction. The wave function of the $I=7/2^{-}$ ground state of the deformed proton emitter $^{141}$Ho is obtained in the adiabatic limit, and a Green's function technique is used to calculate the decay rate and branching ratio to the first excited 2$^{+}$ state of the daughter nucleus. Only for values of the triaxial angle $\gamma$ $<5^{\circ}$ is good agreement obtained for both the total decay rate and the 2$^{+}$ branching ratio.Comment: 19 pages, 4 figure

Extent and Influence of Recreational Drug Use on Men and Women Aged 15 Years and Older in South Africa

Illicit drug use negatively affects development of human and physical capital of any nation. Huge financial resources are allocated to prevent and curb illicit drug use. The use of these drugs continue to spread across race and age groups, despite application of various control measures. The information provided in this paper contributes towards understanding the extent and influence of illicit drugs use in South Africa. A population-based national HIV prevalence, behaviour and health survey conducted in 2008, incorporated questions on the extent and use of illicit drugs. A multistage random population sample of 15 845 persons aged 15 years or older (58% women and 42% men) was included in the survey. The use of combined illicit drugs excluding cannabis was reported by 1.7% of the 13 119 participants, and including cannabis by 4.3 % of the 13 128 participants. The Coloured men (14.3%) were the most likely to use cannabis, where as the Indian women (0.6%) were the least likely. The urban residents (5.4%) were more likely to report use of any illicit drug including cannabis than rural dwellers (2.5%). Illicit drug use has a high association with illnesses thus call for interventions to address this serious problem. Key Words: Recreational drug use, South Africa, illicit drug use, HIV prevalence surve

Semiclassical Limits of Extended Racah Coefficients

We explore the geometry and asymptotics of extended Racah coeffecients. The extension is shown to have a simple relationship to the Racah coefficients for the positive discrete unitary representation series of SU(1,1) which is explicitly defined. Moreover, it is found that this extension may be geometrically identified with two types of Lorentzian tetrahedra for which all the faces are timelike. The asymptotic formulae derived for the extension are found to have a similar form to the standard Ponzano-Regge asymptotic formulae for the SU(2) 6j symbol and so should be viable for use in a state sum for three dimensional Lorentzian quantum gravity.Comment: Latex2e - 26 pages, 6 figures. Uses AMS-fonts, AMS-LaTeX, epsf.tex and texdraw. Revised version with improved clarity and additional result

Alcohol use and problem drinking in South Africa: findings from a national population-based survey

Objective: This study formed part of the South African National HIV, Incidence, Behaviour and Communication (SABSSM) 2008 survey, which included questions assessing the extent of alcohol use and problem drinking among South Africans. Method: A multistage random population sample of 15 828 persons aged 15 or older (56.3% women) was included in the survey. Alcohol use was assessed using the Alcohol Use Identification Test (AUDIT). Tabulation of data for different age groups, geolocality, educational level, income, and population group produced the estimates and associated confidence intervals. The odds ratios for these variables in relation to hazardous or harmful drinking were also computed. Results: Current alcohol use was reported by 41.5% of the men and 17.1% of women. White men (69.8%) were most likely and Indian/Asian women (15.2%) least likely to be current drinkers. Urban residents (33.4 %) were more likely than rural dwellers (18.3%) to report current drinking. Risky or hazardous or harmful drinking was reported by 9%: 17% among men and 2.9% among women. In men, risky drinking was associated with: the 20-54 year age group; the Coloured population group; lower economic status; and lower education. Among women, risky drinking was associated with: urban residence; the Coloured population group; lower education; and higher income. Conclusion: An increase in current, binge drinking and hazardous or harmful drinking prevalence rates was observed from 2005 to 2008 in South Africa. Multilevel interventions are required to target high-risk drinkers and to create awareness in the general population of the problems associated with harmful drinking. Future prospective studies are needed to assess the impact of problem drinking.Key words: Alcohol use; Binge drinking; Hazardous or harmful drinking; Prevalence; National, population-based survey; South Afric