High-pressure Debye-Waller and Grueneisen parameters of Au and Cu

The lattice vibrations are determined in the quasi-harmonic approximation for elemental Au and Cu to twice their normal density by first-principles electronic band-structure calculations. It is found for these materials that the important moments of the phonon density of states can be obtained to high accuracy from short-ranged force constant models. We discuss the implications for the Grueneisen parameters on the basis of calculated phonon moments and their approximations by using bulk moduli and Debye-Waller factors.Comment: 4 pages, 2 figures to appear in the proceedings of the 13th APS Topical Conference on Shock Compression of Condensed Matter (scheduled for April 2004

The Determination of 11B/10B and 87Sr/86Sr Isotope Ratios by Quadrupole-Based ICP-MS for the Fingerprinting of South African Wine

The 11B/10B and 87Sr/86Sr isotope ratios in wines and soils of four major South African wine-producing regions have been determined by quadrupole-based ICP-MSin order to establish a fingerprint for origin verification of the wines. The 11B/10B isotope ratio was found to be a useful tool to distinguish among the wines of the selected wine regions. In addition, the use of B isotope ratios together with elemental concentrations of selected indicator elements as independent variables in a linear discriminant analysis procedure was shown to be a highly successful method to classify wine according to geographical origin. A good correlation between the B and Sr isotope ratios in wine and its provenance soil was found. Both wine and soil samples were prepared using microwave-assisted digestion followed by the isolation of boron and strontium from the sample matrix through element-specific ion exchange. Isotope ratio measurements with good precision, ~0.1 % RSD, for both boron and strontium have been obtained. The 87Sr/86Sr ratio showed limited potential as an indicator of provenance in the wine-producing regions included in this study, since the wines of only one region could be distinguished from the others.Keywords: Boron Isotope Ratio, Strontium Isotope Ratio, ICP-MS, Wine Analysis, Fingerprinting, Provenance Determinatio

Finnsheep and their utilization in crosses with the Merino under range conditions of South-Africa

Two field trials were performed at two localities in a semiarid region to evaluate the performance of Finn (F) x Merino(M) crossbred females. The trials involved 781 F x M ewes and 657 M ewes. Ile de France, S.A. Mutton Merino, Dohne Merino, M, and F x M rams were used for matings. The F x M ewes were superior to M ewes in lambing-%, especially after mating as lambs, and the fecundities were 187and 107 %, resp. Multiple lambs of F x M ewes had better survival rates than those of M ewes. Lambs born from F x M ewes grew faster, had a larger weaning mass, over 10 % longer stables, ca. 2 mm thicker fibres, 30 % lower clean fleece weights, and a little less crimps/25 mm than those born from M ewes. Thus, F x M seemed to provide a suitable and acceptable composite showing remarkable adaptability to harsh environmental conditions. The results from the F x M wool and its special qualities can be regarded as useful attributes. Establishment of a composite F x M female line appeared well-founded

Genetic and phenotypic parameters of pelt traits in a Karakul control flock

Genetic parameters of 16 pelt trais and birth mass were calculated in a Karakul control flock (n =2058; rams= 305) with a half-sib analysis. Moderately high heritabilities were estimated for pelt traits. No antagonistic genetic correlation was found between pattern and hair quality. The genetic correlations between pattern and pelt traits were lower than those estimated for hair quality and the other pelt traits. The expected correlated response from selection for hair quality may be a decrease in the occurrence of brittle hair, hair thickness, metallic, skin thickness, occurence of feathers, hair stiffness and an increase in hair length, lustre and curl breadth. Selection for pattern may result in a decrease in bandedness, a slight increase in lustre and in the occurrence of feathers, and a moderate decrease in curl type and hair length. Genetic estimates obtained in this study are compared with previous estimates obtained in Karakul sheep. Genetiese parameters van 16 pelseienskappe en van geboortemassa is in 'n Karakoelkontrole-kudde( n =2058; ramme = 305) met behulp van die halfsib-metodeb eraam. Matige hoe oorerflikhede is vir pelseienskappe beraam. Geen antagonistiese genetiese korrelasie is tussen patroon en haarkwaliteit gevind nie. Die genetiese korrelasies tussen patroon en ander pelseienskappe was heelwat laer as die tussen haarkwaliteit en die ander pelseienskappe. Die verwagte gekorreleerde responsie van seleksie vir haarkwaliteit mag 'n afname in die voorkoms van breekhare, haardikte, metaalagtigheid, veldikte, voorkoms van vere, haarstyfte, en 'n toename in haarlengte, glans en krulgrootte wees. Seleksie vir patroon mag 'n afname in die voorkoms van bande, 'n effense toename in glans en in die voorkoms van vere en 'n matige afname in krultipe en haarlengte veroorsaak. Genetiese parameters verkry in hierdie studie word met ander studiesb y Karakoelskape vergelyk.Keywords: Karakul, pelt traits, genetic and phenotypic parameters

An integrated social media communication view on content marketing by South African non-profit sectors

Background: Organisations widely adopt social media to communicate with stakeholders, yet research into content marketing in the South African non-profit sector is sparse. It is concerned with consistently producing valuable and relevant content for social media. As it is generally associated with the field of marketing, limited research exists from a communication perspective. This perceived gap in taking a communication stance prompted this investigation into the ways in which these organisations attend to social media content aspects. Objectives: The research objective was to acquire a broad understanding of content marketing on social media, unique to South African non-profit organisations. Key areas that were uncovered and statistically verified in an earlier quantitative study and how these are attended to in real life were explored. Method: A qualitative approach was used to obtain in-depth insights into the use of content marketing. Semi-structured interviews were used as data collection method to explore non-profit sector’s approaches to social media communication, and to determine whether their efforts could be regarded as being integrated. Results: The findings yielded valuable insights into the ways that non-profit sectors in South Africa practise social media communication. The benefits of using social media for communication is acknowledged, yet vital aspects such as sourcing content, considering stakeholders’ needs and demographics communication, using available planning tools and recognising employees as internal ambassadors are not considered. Conclusion: The findings of this study highlight several key areas and topics that organisations should consider an integrated social media communication approach as alternative for content marketing in the non-profit secto

The #FeesMustFall protests in South Africa: Exploring first-year students’ experiences at a peri-urban university campus

Students experienced unique challenges in transitioning to their first-year during the FeesMustFall (#FMF) protest actions. It is important to examine students’ first-year adjustment experiences amidst study disruptions to ensure better outcomes of first-year study experiences. The impact of protest actions on the economy, higher education institutions (HEIs) and the individual student may be harmful when not managed effectively. The current study aims to clarify the first-year experience to explore how South African first-year students enrolled at a peri-urban university campus experienced the #FMF protest actions. The peri-urban university campus serves a large rural catchment area. Using the Mmogo-method® and unstructured individual interviews, researchers gathered in-depth experiences of fifteen participants who provided insight into their subjective experiences of their first-year transitions during the #FMF movement. Thematic analysis resulted in four themes: Clashes between students and police or campus security; the impact of protest actions on students’ lives; psychological experiences of trauma and physical harm; and student attitudes towards and needs in times of crisis. The study uncovered the experiences of first-year students at a peri-urban campus. The knowledge gathered could aid universities to develop proactive measures to minimize the impact of the protest actions or disruptions on the institution itself, students and stakeholders involved

Uricult trio as a screening test for bacteriurla in pregnancy

Objective. To establish the effectiveness in an indigent urban population of Uricult Trio as a screening test for asymptomatic bacteriuria in pregnancy and in diagnosing urinary tract infections (UTI) in symptomatic pregnant women. likelihood ratios were established for positive and negative Uricult Trio test results.Subjects. Two populations of patients from the Pretoria region were involved: (J) asymptomatic pregnant women attending the antenatal clinic for the first time or presenting in labour; and (iI) pregnant women with symptoms suggestive of UTI.Method. A midstream urine specimen was collected from the two populations of patients, plated onto the Uricult Trio and sent to the laboratory for culture.Results. The prevalence of asymptomatic bacteriuria in this population was 23%, and for women with symptoms suggestive of UTI, 29%. The likelihood ratios for a positive test were 1.8 and 1.5 for asymptomatic and symptomatic patients respectively. The likelihood ratios for a negative test were 0.35 and 0.44 for asymptomatic and symptomatic patients respectively. Escherichia coli was the causative agent . in 36% of cases.Conclusion. Uricult Trio is not effective as a screening test for asymptomatic bacteriuria in pregnancy or for diagnosing UTIs in women with symptoms suggestive of infection