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The O16(α,α′) reaction was studied at θlab=0 at an incident energy of Elab=200 MeV using the K600 magnetic spectrometer at iThemba LABS. Proton decay and α decay from the natural parity states were observed in a large-acceptance silicon strip detector array at backward angles. The coincident charged-particle measurements were used to characterize the decay channels of the 06+ state in O16 located at Ex=15.097(5) MeV. This state is identified by several theoretical cluster calculations to be a good candidate for the 4-α cluster state. The results of this work suggest the presence of a previously unidentified resonance at Ex≈15 MeV that does not exhibit a 0+ character. This unresolved resonance may have contaminated previous observations of the 06+ state.

The O-16(alpha, alpha') reaction was studied at theta(lab) = 0 degrees at an incident energy of E-lab = 200 MeV using the K600 magnetic spectrometer at iThemba LABS. Proton decay and a decay from the natural parity states were observed in a large-acceptance silicon strip detector array at backward angles. The coincident charged-particle measurements were used to characterize the decay channels of the theta(+)(6) state in O-16 located at E-x = 15.097(5) MeV. This state is identified by several theoretical cluster calculations to be a good candidate for the 4-alpha cluster state. The results of this work suggest the presence of a previously unidentified resonance at Ex approximate to 15 MeV that does not exhibit a theta(+) character. This unresolved resonance may have contaminated previous observations of the theta(+)(6) state.

Background: Aspects of the nuclear structure of light α-conjugate nuclei have long been associated with nuclear clustering based on α particles and heavier α-conjugate systems such as C12 and O16. Such structures are associated with strong deformation corresponding to superdeformed or even hyperdeformed bands. Superdeformed bands have been identified in Ca40 and neighboring nuclei and find good description within shell model, mean-field, and α-cluster models. The utility of the α-cluster description may be probed further by extending such studies to more challenging cases comprising lighter α-conjugate nuclei such as Mg24, Si28, and S32. Purpose: The purpose of this study is to look for the number and energy of isoscalar 0+ states in Si28. These states are the potential bandheads for superdeformed bands in Si28 corresponding to the exotic structures of Si28. Of particular interest is locating the 0+ bandhead of the previously identified superdeformed band in Si28. Methods: α-particle inelastic scattering from a Sinat target at very forward angles including 0 has been performed at the iThemba Laboratory for Accelerator-Based Sciences in South Africa. Scattered particles corresponding to the excitation energy region of 6 to 14 MeV were momentum-analysed in the K600 magnetic spectrometer and detected at the focal plane using two multiwire drift chambers and two plastic scintillators. Results: Several 0+ states have been identified above 9 MeV in Si28. A newly identified 9.71 MeV 0+ state is a strong candidate for the bandhead of the previously discussed superdeformed band. The multichannel dynamical symmetry of the semimicroscopic algebraic model predicts the spectrum of the excited 0+ states. The theoretical prediction is in good agreement with the experimental finding, supporting the assignment of the 9.71-MeV state as the bandhead of a superdeformed band. Conclusion: Excited isoscalar 0+ states in Si28 have been identified. The number of states observed in the present experiment shows good agreement with the prediction of the multichannel dynamical symmetry.

A search of the literature has not revealed any reference to the development of the reproductive tract of the male springbok or any quantitative studies of the age of appearance of the various germ cells in the spermatogenic cycle. Such a study would be of importance inmaking recommendations for the practical management of young rams and was the object of the present work.

Objectives. To describe the methodology used in a recent survey of HIV/AIDS in South Africa and to present the response rates.Methods. A cross-sectional, national household-based survey was conducted using second-generation surveillance procedures. A complex multistage sampling technique was used to create a master sample of 1 000 census enumerator areas out of a total of 86 000 nationally. Aerial photographs were taken and used to randomly select more than 10 197 households and ultimately 13 518 individuals from a sampling frame of 31 321 people. Phase 1 of the study involved notifying the household residents about the study and collecting key demographic information on respondents aged 2 years and older. This information was used to randomly select up to 3 respondents from each household: 1 adult (25 years and older), 1 youth (15- 24 years), and 1 child (2- 14 years). In phase 2 nurses interviewed respondents and collected oral fluid specimens for HIV testing. In the case of children aged 2 - 11 years, parents or guardians were interviewed, but HIV testing was performed on the selected children. Questionnaire data were anonymously linked with HIV test results.Results. A total of 9 963 persons agreed to be interviewed and 8 840 were tested for HIV, yielding a response rate of 73.7% and 65.4% respectively. However, only 8 428 (62.3%) HIV test results were correctly matched with behavioural data. The results showed that those tested for HIV did not differ from those not tested in terms of key determinants.Conclusion. It is possible to use community-based surveys to study the prevalence of HIV in the general population.

The $\mathrm{^{16}O}(��, ��^{\prime})$ reaction was studied at $��_{lab} = 0^\circ$ at an incident energy of $\textrm{E}_{lab}$ = 200 MeV using the K600 magnetic spectrometer at iThemba LABS. Proton and $��$-decay from the natural parity states were observed in a large-acceptance silicon-strip detector array at backward angles. The coincident charged particle measurements were used to characterize the decay channels of the $0_{6}^{+}$ state in $\mathrm{^{16}O}$ located at $E_{x} = 15.097(5)$ MeV. This state is identified by several theoretical cluster calculations to be a good candidate for the 4-$��$ cluster state. The results of this work suggest the presence of a previously unidentified resonance at $E_{x}\approx15$ MeV that does not exhibit a $0^{+}$ character. This unresolved resonance may have contaminated previous observations of the $0_{6}^{+}$ state.

Objective: The aim of this study was to assess long-term effects for women following the use of magnesium sulphate for pre-eclampsia. Design: Assessment at 2-3 years after delivery for women recruited to the Magpie Trial (recruitment in 1998-2001, ISRCTN 86938761), which compared magnesium sulphate with placebo for pre-eclampsia. Setting: Follow up after discharge from hospital at 125 centres in 19 countries across five continents. Population: A total of 7927 women were randomised at the follow-up centres. Of these women, 2544 were not included for logistic reasons and 601 excluded (109 at a centre where