Current developments in arbuscular mycorrhizal fungi research and its role in salinity stress alleviation a biotechnological perspective
- Authors: Kumar, Ashwani , Dames, Joanna F , Gupta, Aditi , Sharma, Satyawati , Gilbert, Jack A , Ahmad, Parvaiz
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443998 , vital:74177 , https://doi.org/10.3109/07388551.2014.899964
- Description: Arbuscular mycorrhizal fungi (AMF) form widespread symbiotic associations with 80% of known land plants. They play a major role in plant nutrition, growth, water absorption, nutrient cycling and protection from pathogens, and as a result, contribute to ecosystem processes. Salinity stress conditions undoubtedly limit plant productivity and, therefore, the role of AMF as a biological tool for improving plant salt stress tolerance, is gaining economic importance worldwide. However, this approach requires a better understanding of how plants and AMF intimately interact with each other in saline environments and how this interaction leads to physiological changes in plants. This knowledge is important to develop sustainable strategies for successful utilization of AMF to improve plant health under a variety of stress conditions. Recent advances in the field of molecular biology, “omics” technology and advanced microscopy can provide new insight about these mechanisms of interaction between AMF and plants, as well as other microbes. This review mainly discusses the effect of salinity on AMF and plants, and role of AMF in alleviation of salinity stress including insight on methods for AMF identification. The focus remains on latest advancements in mycorrhizal research that can potentially offer an integrative understanding of the role of AMF in salinity tolerance and sustainable crop production.
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- Date Issued: 2015
Labour after globalisation: old and new sources of power
- Authors: Webster, Edward
- Date: 2015
- Subjects: Globalization Labor market Labor and globalization Labor and economy Labor economics Labor supply -- Effect of automation on
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/3093 , vital:20368 , ISBN 9780868104867
- Description: In this paper I focus on building a conceptual framework for an understanding of the changing dynamics of labour and workers’ sources of power. I begin by identifying worker action that draws on traditional sources of structural and associational power. I then show how the emergence of new forms of labour action is drawing on both old and new sources of power. New global forms of worker power are examined, and I conclude by suggesting that the missing dimension in the three sources of power identified – structural, associational and societal – is institutional power. If these new initiatives are to be sustainable they will need to include one of labour’s traditional sources of power, institutional power. These four-fold sources of power provide the basis for a strategy of union renewal in the age of globalisation.
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- Date Issued: 2015
Patriarchy, women, land and livelihoods on A1 farms in Zimbabwe
- Authors: Chiweshe, Manase K , Chakona, Loveness , Helliker, Kirk D
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71204 , vital:29812 , https://doi.org/10.1177/0021909614541083
- Description: In this article, we focus on patriarchy, women, land and livelihoods on A1 farms in Zimbabwe which arose from the fast track land reform programme. There is now significant literature on A1 farms in Zimbabwe. These studies include a number of ethnographic and comparative studies but this literature does not give sustained attention to patriarchy and women. In addition, though, a small number of works have appeared based upon a more focused gender analysis. We draw upon this more focused literature and offer fresh fieldwork evidence based on recent studies undertaken by two of the authors, in Goromonzi and Mazowe districts. At times, radical socio-spatial reorganisation such as fast track may destabilise systems of patriarchy. In the case of fast track, there has been a reconfiguration of relations between men and women yet this is uneven and contradictory and remains within the confines of patriarchal structures, practices and discourses. At the same time, women have manoeuvred and negotiated at local levels to enhance their lives and livelihoods.
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- Date Issued: 2015
Some implications of MetaReality for environmental educators
- Authors: Price, Leigh
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437034 , vital:73325 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
- Description: This chapter seeks to illuminate the use of dialectical critical realism in a PhD study that was conducted to explore and expand learning processes in sustain able agriculture work-place contexts (Mukute, 2010). The study was conducted in three case study sites in Leso-tho, South Africa and Zimbabwe. About 80 people in three study sites participated in the multiple case study research. In Zimbabwe the study was located in Hwedza District, St Margaret Primary School and its community that learns, practises and facilitates the learn-ing of Permaculture within the Schools and Colleges Permaculture Programme (SCOPE). In South Africa the study took place in Durban urban and peri-urban areas where a communi-ty of organic farmers, facilitators and entrepreneurs co-ordinated the marketing of their produce through Isidore Farm and Earth Mother Organic and support each other to learn and practise organic farming. In Lesotho the study took place in the Mafeteng and Mohale’s Hoek districts where the focus was on farmers who learn and practise the Machobane Farming System (MFS) and were supported in this by the Rural Self Development As-sociation (RSDA) and the Machobane Agricultural Develop-ment Foundation (MADF ). The other research participants were agricultural extension workers who tend to promote high external input agriculture, sustain able agriculture researchers and organic produce marketers.
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- Date Issued: 2015
Stigma resistance in online child free communities : the limitations of choice rhetoric
- Authors: Morison, Tracy , Macleod, Catriona I , Lynch, Ingrid , Mijas, Magda , Shivakumar, Seemanthini T
- Date: 2015
- Language: English
- Type: Article
- Identifier: vital:6311 , http://hdl.handle.net/10962/d1019799 , http://journals.sagepub.com/doi/10.1177/0361684315603657
- Description: People who are voluntarily childless, or ‘‘childfree,’’ face considerable stigma. Researchers have begun to explore how these individuals respond to stigma, usually focusing on interpersonal stigma management strategies. We explored participants’ responses to stigma in a way that is cognisant of broader social norms and gender power relations. Using a feminist discursive psychology framework, we analysed women’s and men’s computer-assisted communication about their childfree status. Our analysis draws attention to ‘‘identity work’’ in the context of stigma. We show how the strategic use of ‘‘choice’’ rhetoric allowed participants to avoid stigmatised identities and was used in two contradictory ways. On the one hand, participants drew on a ‘‘childfree-by-choice script,’’ which enabled them to hold a positive identity of themselves as autonomous, rational, and responsible decision makers. On the other hand, they mobilised a ‘‘disavowal of choice script’’ that allowed a person who is unable to choose childlessness (for various reasons) to hold a blameless identity regarding deviation from the norm of parenthood. We demonstrate how choice rhetoric allowed participants to resist stigma and challenge pronatalism to some extent; we discuss the political potential of these scripts for reproductive freedom.
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- Date Issued: 2015
'Joining the academic life': South African students who succeed at university despite not meeting standard entry requirements
- Authors: Vincent, Louise , Idahosa, Grace E
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141745 , vital:38001 , https://hdl.handle.net/10520/EJC159177
- Description: At present the Swedish points system is one of the main determinants of an applicant either being granted or refused entry into many South African higher education institutions (HEIs). Using a grounded theory approach, this article interprets the experiences of participants whose school performance and therefore university 'entry points' were lower than the expected norm. Despite not meeting standard university entry requirements, these students succeeded at university, completing their degrees in the minimum time available and going on to higher degrees. The journey of these participants - from low entry points to academic success - suggests that points based on school performance are not necessarily the best way of identifying students' potential to succeed in the contemporary South African educational context. If their entry points were not a good indication of their ability to thrive at university, the article asks, what is it about these participants that accounts for their success? And what implications does this have for South African practice, not only with regard to admissions policies but also in relation to the responsibilities of HEIs to students once they are admitted?
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- Date Issued: 2014
Critical spaces: processes of othering in British Institutions of Higher Education
- Authors: Phiri, Aretha
- Date: 2014
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60741 , vital:27824 , http://www.jfsonline.org/issue7-8/articles/phiri/
- Description: Global recession and the economic crisis have affected contemporary British society in predictable ways. But this age of austerity has also unveiled the continued sinister machinations of whiteness. While not necessarily homogeneous, austerity rhetoric, as it is currently conventionally deployed, works to perpetuate white masculinist privilege and further entrenches the normative value of whiteness, while simultaneously masking and marginalizing those ethnic minority populations traditionally othered from mainstream sociopolitical discourse. More specifically, recent austerity measures adversely affect the situation of women and the future of feminist theory and practice in British higher education. This paper investigates and problematizes the deployment of austerity discourse within higher learning for its perpetuation of the normativity and hegemony of a masculinist whiteness, which further disadvantages (white) women and disrupts the practice of feminism(s) in academia.
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- Date Issued: 2014
Expurgating the Monstrous: an analysis of the South African Daily Sun's coverage of gang rape
- Authors: Boshoff, Priscilla A , Prinsloo, Jeanne
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143436 , vital:38246 , DOI: 10.1080/14680777.2014.903286
- Description: The most widely read South African tabloid, the Daily Sun, covered the “Soweto gang rape” in 2012. These acts were recorded by the perpetrators on mobile phones and “went viral” as the media continuously noted. We draw on the concept of provider love that informs relations of intimacy in certain South African spaces, central to which is its materiality and the assumption that a “real” man is able to command material resources, a prerequisite for having both a girlfriend and sex. For working class and township youth these possibilities are constrained and their sense of being left behind is lived in gendered ways with violent masculinities becoming a marker of tough sexual masculinity. Informed by Foucauldian understandings of discourse, the paper undertakes a close reading of this coverage, including the reporting, editorials, and letters. If those arrested for rape are constituted as monstrous, the analysis indicates how the responses are similarly vengeful. These responses deny the forms of masculinity produced within these marginalised spaces and foreclose on other possibilities for understanding these violent acts.
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- Date Issued: 2014
Phylogeny of the family Trogidae (Coleoptera: Scarabaeoidea) inferred from mitochondrial and nuclear ribosomal DNA sequence data
- Authors: Strümpher, Werner P , Sole, Catherine L , Villet, Martin H , Scholtz, Clarke H
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442253 , vital:73970 , https://doi.org/10.1111/syen.12074
- Description: Trogidae constitute a monophyletic and biologically unique family within Scarabaeoidea, being the only keratinophagous group in the superfamily. Traditionally, the family has been divided into three distinctive genera, Polynoncus Burmeister, Omorgus Erichson and Trox Fabricius. Although the taxonomy of the group is relatively well studied, changes to the existing classification have recently been proposed and the family as currently constituted has not been subjected to phylogenetic analyses. Here we present a molecular phylogeny for this cosmopolitan family based on three partially sequenced gene regions: 16S rRNA, 18S rRNA and 28S rRNA (domain 2). Included in the analyses are representatives belonging to four of the five extant genera (and three of the four subgenera) from all major zoogeographic regions, representing about 20% of the known trogid species diversity in the family. Phylogenetic analyses performed included parsimony and Bayesian inference. We deduce their historical biogeography by using trogid fossils as calibration points for divergence estimates. Our analyses resolved relationships between and within genera and subgenera that are largely congruent with existing phylogeny hypotheses based on morphological data. We recovered four well‐supported radiations: Polynoncus, Omorgus, Holarctic Trox and African Phoberus MacLeay. On the basis of this study, it is proposed that taxonomic changes to the generic classification of the family be made. The subgenera Trox and Phoberus should be elevated to genera to include the Holarctic and all the Afrotropical species, respectively, and Afromorgus returned to subgeneric rank. Estimates of divergence time are consistent with a Pangaean origin of the family in the Early Jurassic. The subsequent diversification of the major lineages is largely attributed to the break‐up of Pangaea and Gondwana in the Middle Jurassic and early Late Cretaceous, respectively.
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- Date Issued: 2014
Vice-Chancellor's 2014 Address to Graduation Ceremonies
- Authors: Badat, Saleem
- Date: 2014
- Language: English
- Type: text
- Identifier: vital:7868 , http://hdl.handle.net/10962/d1016417
- Full Text:
- Date Issued: 2014
Assessment of potential anti-cancer stem cell activity of marine algal compounds using an in vitro mammosphere assay:
- Authors: de la Mare, Jo-Anne , Sterrenberg, Jason N , Sukhthankar, Mugdha G , Chiwakata, Maynard T , Beukes, Denzil R , Blatch, Gregory L , Edkins, Adrienne L
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165184 , vital:41216 , DOI: 10.1186/1475-2867-13-39
- Description: The cancer stem cell (CSC) theory proposes that tumours arise from and are sustained by a subpopulation of cells with both cancer and stem cell properties. One of the key hallmarks of CSCs is the ability to grow anchorage-independently under serum-free culture conditions resulting in the formation of tumourspheres. It has further been reported that these cells are resistant to traditional chemotherapeutic agents.
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- Date Issued: 2013
Ecological niche modeling of the invasive potential of Nile tilapia Oreochromis niloticus in African river systems: concerns and implications for the conservation of indigenous congenerics
- Authors: Zengeya, Tsungai A , Robertson, Mark P , Booth, Anthony J , Chimimba, Christian T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124341 , vital:35596 , https://doi.10.1007/s10530-012-0386-7
- Description: This study applied ecological niche models to determine the potential invasive range of Nile tilapia, Oreochromis niloticus, with a particular focus on river systems in southern Africa where it is now established and spreading. Computational tools such as niche models are useful in predicting the potential range of invasive species, but there are limitations to their application. In particular, models trained on native records may fail to predict the full extent of an invasion. This failure is often attributed to changes in either the niche of the invading species or the variables used to develop the models. In this study, we therefore evaluated the differences in the predictive power of models trained with different environmental variables, the effect of species range (native vs. introduced) on model performance and assessed whether or not there is evidence suggestive of a niche shift in Nile tilapia following its introduction. Niche models were constructed using Maxent and the degree of niche similarity was assessed using Schoener‘s index. Null models were used to test for significance. Model performance and niche conservatism varied significantly with variable selection and species range. This indicates that the environmental conditions available to Nile tilapia in its native and introduced ranges are not congruent. Nile tilapia exhibited broad invasive potential over most of southern Africa that overlaps the natural range of endemic congenerics. Of particular concern are areas which are free of exotic species but are now vulnerable due to the promotion of fish introductions mainly for aquaculture and sport fishing.
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- Date Issued: 2013
Genetic approaches to improve salinity tolerance in plants
- Authors: Kumar, Ashwani , Gupta, Aditi , Azooz, M M , Sharma, S , Ahmad, Parvaiz , Dames, Joanna F
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/453449 , vital:75255 , ISBN , https://doi.org/10.1007/978-1-4614-6108-1_4
- Description: Abiotic stress tolerance in plants is gaining importance day by day. Different techniques are being employed to develop salt tolerant plants that directly or indirectly combat global food problems. Advanced comprehension of stress signal perception and transduction of associated molecular networks is now possible with the development in functional genomics and high throughput sequencing. In plant stress tolerance various genes, proteins, transcription factors, DNA histone-modifying enzymes, and several metabolites are playing very important role in stress tolerance. Determination of genomes of Arabidopsis, Oryza sativa spp. japonica cv. Nipponbare and integration of omics approach has augmented our knowledge pertaining to salt tolerance mechanisms of plants in natural environments. Application of transcriptomics, metabolomics, bioinformatics, and high-through-put DNA sequencing has enabled active analyses of regulatory networks that control abiotic stress responses. To unravel and exploit the function of genes is a major challenge of the post genomic era. This chapter therefore reviews the effect of salt stress on plants and the mechanism of salinity tolerance along with contributory roles of QTL, microRNA, microarray and proteomics.
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- Date Issued: 2013
The Evil of sluits : a re-assessment of soil erosion in the Karoo of South Africa as portrayed in century-old sources
- Authors: Rowntree, Kate M
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6725 , http://hdl.handle.net/10962/d1006803
- Description: Deep, linear gullies are a common feature of the present landscape of the Karoo of South Africa, where they were known locally in the early twentieth century as ‘sluits’. Recent research has shown that many of these features are now stable and are no longer significant sediment sources, although they are efficient connectors in the landscape. Because most of the gully networks predate the first aerial photographs, little is known in the scientific literature about the timing of their formation. One secondary source, however, throws interesting light on the origin of these features, and the early response by landowners to their rehabilitation. The Agricultural Journal of the Cape of Good Hope at the turn of the Twentieth Century carried a number of articles by farmers and agricultural officers concerning the "evil of sluits". The authors gave accounts of widespread incision of valley bottoms by deep, wide gullies. Many of these gullies had been in existence for some thirty years but apparently had formed within living memory. A number of attempts to prevent further erosion had been put in place at the time of writing. This paper presents a review of land degradation, specifically gully erosion, and rehabilitation recommendations as given by authors writing in this journal. It reflects on the findings in the context of assessing land degradation processes through the local knowledge portrayed in the journal.
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- Date Issued: 2013
A review of the alderfly genus Leptosialis Esben-Petersen (Megaloptera, Sialidae) with description of a new species from South Africa
- Authors: Price, Benjamin W , Liu, Xingyue , de Moor, Ferdy C , Villet, Martin H
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441461 , vital:73891 , https://zookeys.pensoft.net/articles.php?id=2856
- Description: The monotypic South African alderfly genus Leptosialis Esben-Petersen, 1920 is reviewed and Leptosialis africana Esben-Petersen, 1920 is redescribed. In the process a new species of alderfly Leptosialis necopinata sp. n. from the Eastern Cape and KwaZulu-Natal provinces of South Africa is recognised and described. Within Sialidae the new species most closely resembles Leptosialis africana. A key to the two species of Leptosialis using both adult and larval characters is provided.
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- Date Issued: 2012
Dynamics of a lattice Universe : the dust approximation in cosmology
- Authors: Bruneton, J-P , Larena, Julien
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6789 , http://hdl.handle.net/10962/d1006941
- Description: We find a solution to Einstein field equations for a regular toroidal lattice of size L with equal masses M at the centre of each cell; this solution is exact at order M/L. Such a solution is convenient to study the dynamics of an assembly of galaxy-like objects. We find that the solution is expanding (or contracting) in exactly the same way as the solution of a Friedman–Lemaître–Robertson–Walker Universe with dust having the same average density as our model. This points towards the absence of backreaction in a Universe filled with an infinite number of objects, and this validates the fluid approximation, as far as dynamics is concerned, and at the level of approximation considered in this work.
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- Date Issued: 2012
Ethical deliberations in environmental education workplaces: a case story of contextualised and personalised reflexivity
- Authors: Olvitt, Lausanne L
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437421 , vital:73377 , ISBN 9789086867578 , https://doi.org/10.3920/9789086867578_0010
- Description: This chapter explores the fluidity and complexity of individual ethical deliberations in an environmental education workplace and ‘teases out’the associated learning processes. Based on the author’s recent doctoral research, the chapter tells the story of one South African environmental educator grappling with environmentoriented ethical tensions in his work. These ten-sions range from immediate officebased concerns such as paper wastage, to wider concerns such as lowering his carbon footprint through his choice of transport. The environmental educator has recently completed a one-year part-time course in environmental education. Does the course’s new capital of concepts and terminology influence his ethical deliberations? Does learning about environmental philosophies and other people’s ethical dilemmas support him to deepen his engage-ment with ethical tensions in his ownwork? The case study suggests that course-based learning processes are not espe-cially influential until they interface with the multi-layered soci-ocultural and historical dynamics in work-based and home-based ethical deliberations. Deciding what is ‘right’, and then teaching others about that ‘rightness’ is not as simple as know-ing the facts or norms, and acting on them. Past experiences, cultural norms, religious convictions, power gradients and even logistical constraints, all influence the nature and outcome of individual ethical deliberations, as do people’s future aspira-tions and their professional identities as environmental educa-tors.
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- Date Issued: 2012
Molecular phylogenetics of Oestroidea (Diptera: Calyptratae) with emphasis on Calliphoridae: insights into the inter-familial relationships and additional evidence for paraphyly among blowflies
- Authors: Marinho, M A T , Junqueira, A C M , Paulo, D F , Esposito, M C T , Villet, Martin H , Azeredo-Espin, A D
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442691 , vital:74023 , https://doi.org/10.1016/j.ympev.2012.08.007
- Description: The superfamily Oestroidea, comprising ∼15,000 species, is a large and ecologically diverse clade within the order Diptera. Among its six commonly recognized families, Calliphoridae seems to be crucial for understanding evolutionary relationships in the group, as it is recognized as a controversial paraphyletic grouping. To further investigate this matter, the ITS2, 28S, COI and 16S regions were used to infer phylogenetic relationships in Oestroidea with maximum-parsimony (MP), maximum-likelihood (ML) and Bayesian inference (BI) methods. For the BI analyses, a deep evaluation of different data partitioning strategies was conducted, including consideration of structural conformation (ITS2 and 16S) and codon position (COI) information.
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- Date Issued: 2012
Quinones and halogenated monoterpenes of algal origin show anti-proliferative effects against breast cancer cells in vitro:
- Authors: de la Mare, Jo-Anne , Lawson, Jessica C , Chiwakata, Maynard T , Beukes, Denzil R , Blatch, Gregory L , Edkins, Adrienne L
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165165 , vital:41214 , DOI: 10.1007/s10637-011-9788-0
- Description: Red and brown algae have been shown to produce a variety of compounds with chemotherapeutic potential. A recent report described the isolation of a range of novel polyhalogenated monoterpene compounds from the red algae Plocamium corallorhiza and Plocamium cornutum collected off the coast of South Africa, together with the previously described tetraprenylquinone, sargaquinoic acid (SQA), from the brown algae Sargassum heterophyllum. In our study, the algal compounds were screened for anti-proliferative activity against metastatic MDA-MB-231 breast cancer cells revealing that a number of compounds displayed anti-cancer activity with IC50 values in the micromolar range. A subset of the compounds was tested for differential toxicity in the MCF-7/MCF12A system and five of these, including sargaquinoic acid, were found to be at least three times more toxic to the breast cancer than the non-malignant cell line.
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- Date Issued: 2012
Rewrite, revise, refine, reflect, rethink: the long and short of teaching journalism at Rhodes
- Authors: Garman, Anthea
- Date: 2012
- Language: English
- Type: Text
- Identifier: vital:585 , http://hdl.handle.net/10962/d1018945 , https://orcid.org/0000-0002-8715-8542
- Description: Vice-Chancellor’s 2011 Senior Distinguished Teaching Award lecture, 10 October 2012
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- Date Issued: 2012