List of Titles

The Marinkas Quellen Carbonatite Complex, southern Namibia: carbonatite magmatism with an uncontaminated depleted mantle signature in a continental setting

- Smithies, Robert H, Marsh, Julian S

Authors: Smithies, Robert H , Marsh, Julian S
Date: 1998
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/149736 , vital:38879 , https://doi.org/10.1016/S0009-2541(98)00029-1
Description: The Marinkas Quellen Carbonatite Complex, in southern Namibia, forms part of the ca. 490–550 Ma Kuboos-Bremen Igneous Province, a zone of alkaline igneous rocks that intrude the Mesoproterzoic to Paleoproterozoic Namaqualand Metamorphic Province and Neoproterozoic platform sediments. The carbonatite complex includes Ca-rich, Mg-rich and Fe-rich carbonatites as well as late ferrocarbonatite dykes that show extreme enrichments in Mn, REE and Th. Compared to most carbonatites, those at Marinkas Quellen are generally depleted in most trace elements, particularly Ba and the LREE.
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Date Issued: 1998

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Distinct kimberlite pipe classes with contrasting eruption processes

- Skinner, E M W, Marsh, Julian S

Authors: Skinner, E M W , Marsh, Julian S
Date: 2004
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/150603 , vital:38988 , https://doi.org/10.1016/j.lithos.2004.03.044
Description: Field and Scott Smith [Field, M., Scott Smith, B.H., 1999. Contrasting geology and near-surface emplacement of kimberlite pipes in southern Africa and Canada. Proc. 7th Int. Kimb. Conf. (Eds. Gurney et al.) 1, 214–237.] propose that kimberlite pipes can be grouped into three types or classes. Classical or Class 1 pipes are the only class with characteristic low temperature, diatreme-facies kimberlite in addition to hypabyssal- and crater-facies kimberlite. Class 2 and 3 pipes are characterized only by hypabyssal-and crater-facies kimberlite.
Full Text: false
Date Issued: 2004

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A passive auxiliary circuit with interphase transformer applied in 12-pulse converters to provide clean power utility interface

- Shih, Der-Chun, Young, Chung-Ming, Whiteley, Chris G

Authors: Shih, Der-Chun , Young, Chung-Ming , Whiteley, Chris G
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/67095 , vital:29031 , https://doi.org/10.1080/02533839.2016.1230029
Description: publisher version , This paper proposes a passive auxiliary circuit which can be added to an interphase transformer (PAC + IPT) configuration to reduce the total harmonic distortion (THD) existing in 12-pulse diode rectifier converter systems at AC mains. The proposed PAC + IPT compensation method is a simple structure, with low power consumption and requires no extra DC power supply. We present the theoretical analysis of the proposed topology that lessens the total harmonic distortion (THD) and evaluate the dynamic simulation results on a 12-pulse converter system and a 3-kW laboratory prototype. Both the simulation and the experimental results show that the proposed PAC + IPT compensation method can improve the power quality and provide a clean power utility interface of AC line input currents for a conventional 12-pulse diode rectifier converter.
Full Text: false
Date Issued: 2016

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Application of the Morita-Baylis-Hillman reaction in the synthesis of 3-[(N-cycloalkylbenzamido)methyl]-2-quinolones as potential HIV-1 integrase inhibitors

- Sekgota, Khethobole C, Majumder, Swarup, Isaacs, Michelle, Mnkandhla, Dumisani, Hoppe, Heinrich C, Khanye, Setshaba D, Kriel, Frederik H, Coates, Judy, Kaye, Perry T

Authors: Sekgota, Khethobole C , Majumder, Swarup , Isaacs, Michelle , Mnkandhla, Dumisani , Hoppe, Heinrich C , Khanye, Setshaba D , Kriel, Frederik H , Coates, Judy , Kaye, Perry T
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66178 , vital:28913 , https://doi.org/10.1016/j.bioorg.2017.09.015
Description: publisher version , A practicable six-step synthetic pathway has been developed to access a library of novel 3-[(N-cycloalkylbenzamido)methyl]-2-quinolones using Morita-Baylis-Hillman methodology. These compounds and their 3-[(N-cycloalkylamino)methyl]-2-quinolone precursors have been screened as potential HIV-1 integrase (IN) inhibitors. A concomitant survey of their activity against HIV-1 protease and reverse-transcriptase reveals selective inhibition of HIV-1 IN.
Full Text: false
Date Issued: 2017

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Transcending objectifications and dualisms: farm workers and civil society in contemporary Zimbabwe

- Sadomba, Zvakanyorwa W, Helliker, Kirk D

Authors: Sadomba, Zvakanyorwa W , Helliker, Kirk D
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/71242 , vital:29822 , https://doi.org/10.1177/0021909609357417
Description: In the academic literature, civil society is often conceptualized in terms of objectifications and subject—object dichotomies. This is the case with regard to both social movements and non-governmental organizations. This article seeks to transcend such argumentation by providing ‘thick descriptions’ of the agency of farm workers and civil society in the context of land reform in contemporary Zimbabwe. We examine a land-based social movement (and the role of farm workers within it) and the involvement of a particular non-governmental organization in farm worker livelihoods. On this basis, we offer a re-formulation of civil society as a social field marked by ambivalences and tensions.
Full Text: false
Date Issued: 2010

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The geochemistry of potassic lavas from Vulsini, central Italy and implications for mantle enrichment processes beneath the Roman region

- Rogers, N W, Hawkesworth, C J, Parker, R J, Marsh, Julian S

Authors: Rogers, N W , Hawkesworth, C J , Parker, R J , Marsh, Julian S
Date: 1985
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/136034 , vital:37330 , https://doi.org/10.1007/BF00378265
Description: Major and trace element and 143Nd/144Nd (0.51209–0.51216) and 87Sr/86Sr (0.70879–0.71105) isotope analyses are presented on a representative group of lavas from the Vulsini district of the Roman magmatic province. Three distinct series are identified; the high-K and low-K series are similar to those described from other Italian volcanoes, while the third is represented by a group of relatively undifferentiated leucite basanites which are thought to be near-primary mantle melts.
Full Text: false
Date Issued: 1985

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Legal ethics education in South Africa: possibilities, challenges and opportunities

- Robertson, Michael, Kruuse, Helen

Authors: Robertson, Michael , Kruuse, Helen
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/68941 , vital:29341 , http://dx.doi.org/10.1080/02587203.2016.1210934
Description: Publisher version , The South African legal profession has been subject to harsh criticism in the last few years, leading to what some have called ‘an ethical crisis.’ Although this perception may or may not be warranted, there have been numerous calls for improved ethical legal practices by South African lawyers. This article seeks to contribute to a discussion about the importance of implementing legal ethics education in South African law schools. The authors (a) explore the meaning of ‘ethical legal practice’ by reference to the international literature; (b) examine the way in which legal ethics has so far been presented in the limited South African literature on the topic; (c) argue the need for a more thorough and critical literature on South African lawyers’ ethics, coupled with a commitment to developing a stronger legal ethics culture within the profession and the legal academia; and (d) suggest a possible approach for South African legal ethics education in the future, with reference to recent developments in other countries.
Full Text: false
Date Issued: 2016

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Shadow of the Sun – the distribution of wellbeing in Sub-Saharan Africa

- Roberts, Benjamin J, Gordon, Steven Lawrence, Moller, Valerie, Struwig, Jare

Authors: Roberts, Benjamin J , Gordon, Steven Lawrence , Moller, Valerie , Struwig, Jare
Date: 2015
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/67235 , vital:29062 , https://doi.org/10.1007/978-94-017-9178-6_23
Description: publisher version , Despite the enthusiasm that prevailed during sub-Saharan Africa’s initial wave of independence, representations of quality of life in the region over the last half-century focused on themes that typically characterize failed states: maladministration, violence and conflict, disease, impoverishment and suffering. Although considerable hardship persists, the subcontinent experienced impressive economic growth over the last decade. This, together with increasing gains from state-led social spending, has prompted a new narrative that speaks of promise and opportunity. Against this backdrop, the chapter reviews quality of life in the region using select objective and subjective wellbeing measures. The results confirm the general pattern of recent social progress, though lingering deprivation, inequality and often difficult political conditions. While this situation is reflected in relatively low life satisfaction evaluations, it is also accompanied by a resolute optimism that attests to the resilience of the region’s citizens in the face of adversity. The chapter also assesses the influence of certain objective conditions on subjective wellbeing at the macro-level.
Full Text: false
Date Issued: 2015

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Developmental and spatial variations in the diet signatures of hyperbenthic shrimp Nauticaris marionis at the Prince Edward Islands based on stable isotope ratios and fatty acid profiles

- Richoux, Nicole B, Allan, Elizabeth L, Froneman, P William

Authors: Richoux, Nicole B , Allan, Elizabeth L , Froneman, P William
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/67923 , vital:29169 , https://doi.org/10.1016/j.csr.2016.02.0131
Description: Publisher version , The caridean shrimp Nauticaris marionis is an ecologically important species in the benthic community around the sub-Antarctic Prince Edward Islands (PEI) as it represents a key prey item for a variety of top predators breeding on the islands. We hypothesized that the diet of N. marionis shifts during its development, and that spatial variability in food availability results in differentiation in the diet signatures of specimens collected from various locations of the shelf waters around the PEI. Specimens were collected from nine stations (depth range 70 to 240 m) around the PEI at inter-island shelf (from west to east: upstream, between and downstream) and nearshore regions during austral autumn 2009. Stable isotope and fatty acid data both revealed spatial and developmental variations in the shrimp diet. Nearshore shrimp were more 13C-enriched than those from the inter-island region, suggesting increased kelp detritus entered the food web in the nearshore regions. The shrimp showed increases in δ13C and δ15N signatures (and trophic position) with an increase in body size, resulting in distinctions between size classes that reflected shifts in their trophic niche through development. The fatty acid profiles similarly indicated distinctions in diet with increased shrimp size (in the deep regions), and spatial variability was evident in relation to region and depth. All shrimp contained large proportions of polyunsaturated and essential fatty acids, indicating that the quality of food consumed was similar between regions despite the diet variability. Our results provide new dietary information about a key species operating near the base of the food web at the highly productive PEI, and show that there were no areas of enhanced nutrition available to the shrimp. As such, there was no nutritional advantage to shrimp inhabiting any specific region around the PEI.
Full Text: false
Date Issued: 2016

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Stable isotope ratios indicate differential omnivory among syntopic rocky shore suspension-feeders

- Richoux, Nicole B, Vermeulen, Ilke, Froneman, P William

Authors: Richoux, Nicole B , Vermeulen, Ilke , Froneman, P William
Date: 2014
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/68261 , vital:29224 , https://doi.org/10.1007/s00227-013-2358-6
Description: Publisher version , We utilised stable isotope ratios to assess differences in diet among three indigenous and syntopic rocky shore suspension-feeders (mussels Perna perna, barnacles Tetraclita serrata, and polychaetes Gunnarea gaimardi). We also determined the spatial and temporal variability in the suspension-feeder diets by collecting specimens on two occasions from two regions adjacent to hydrologically distinct river mouths (i.e. one with larger annual freshwater throughput than the other). The results showed that the isotopic niches (used as proxies for trophic niches) of the three species did not overlap and that the barnacles occupied a trophic position (3.4) well above those of the mussels (2) and polychaetes (2.6). We ascribed the interspecific differences primarily to the disparate feeding mechanisms used by the species. Large-scale regional (~50 km) differences in suspension-feeder diets were apparent, but not small-scale (up to a few km north and south of each estuary mouth). The regional differences in diet resulted from the increased availability of estuarine-origin suspended particulate matter (SPM) and zooplankton in the region adjacent to the river with relatively larger freshwater output, although overall incorporation of zooplankton versus mixed SPM into consumer diets was relatively consistent between regions and through time. Temporal shifts in suspension-feeder diets were apparent from stable carbon isotope ratios in the consumers. Our results showcase the measurable effects of regional-scale processes that can alter the food sources for dominant primary consumers in the rocky intertidal, thus potentially affecting entire food webs through bottom-up processes. The clear evidence for trophic niche partitioning offers valuable insights into how potentially strong competitors can coexist.
Full Text: false
Date Issued: 2014

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The Guinea pigs of a problem-based learning curriculum

- Reddy, Sarasvathie, McKenna, Sioux

Authors: Reddy, Sarasvathie , McKenna, Sioux
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66730 , vital:28987 , ISSN 1470-3300 , https://doi.org/10.1080/14703297.2014.959542
Description: Publisher version , Participants in a study on learning the clinical aspects of medicine in a problem-based learning (PBL) curriculum repeatedly referred to themselves as ‘Guinea pigs’ at the mercy of a curriculum experiment. This article interrogates and problematises the ‘Guinea pig’ identity ascribed to and assumed by the first cohort of students who undertook a PBL curriculum. The article suggests that a range of issues may have come into play in the unfortunate events reported on here, and focuses on the participants’ reported experiences of marginalisation during their clinical education modules in the hospital wards. The impact of power differentials on identity formation was found to be exacerbated by the ‘Guinea pig’ characterisation.
Full Text: false
Date Issued: 2016

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