List of Titles

Water volume differentially modifies copepod predatory strengths on two prey types

- Cuthbert, Ross N, Sithagu, Rotondwa, Weyl, Olaf L F, Froneman, P William, Wasserman, Ryan J, Dick, Jaimie T A, Callaghan, Amanda, Foord, Stefan, Dalu, Tatenda

Authors: Cuthbert, Ross N , Sithagu, Rotondwa , Weyl, Olaf L F , Froneman, P William , Wasserman, Ryan J , Dick, Jaimie T A , Callaghan, Amanda , Foord, Stefan , Dalu, Tatenda
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/466979 , vital:76804 , https://doi.org/10.1016/j.limno.2020.125747
Description: Predatory interaction strengths are highly context-dependent, and in temporary aquatic ecosystems, may be affected by water volume changes. We examine the influence of water volume on Lovenula raynerae (Copepoda) functional responses towards two temporary pond prey types. Daphnia prey risk was not affected by increasing water volume, whereas for Culex prey risk was reduced. Accordingly, water volume changes through the hydroperiod may have species-specific effects on prey, with implications for population persistence under environmental change.
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Date Issued: 2020

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Water, Transport, Oil and Food: A Political–Economy–Ecology Lens on Changing Conceptions of Work, Learning and Skills Development in Africa

- Lotz-Sisitka, Heila

Authors: Lotz-Sisitka, Heila
Date: 2023
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/434894 , vital:73114 , ISBN 978-1529224634 , https://bristoluniversitypress.co.uk/transitioning-vocational-education-and-training-in-africa
Description: Not enough has been said about the kinds of skills develop-ment that are needed if we are to stem the rising tides and impacts of political economies that have been driving what some call ‘fossil capital’(Malm, 2016). In this book, we are producing an emerging argument that it is necessary to also rethink and reframe vocational education and training (VET) logics and approaches if we are to fully consider the implica-tions of a warming future. This chapter provides the context of why this is such an urgent challenge and some thinking tools for understanding where we have come from and where we need to go. The prognosis is that it is now almost impossible to stop global warming below 2oC. The 2021 In-tergovernmental Panel on Climate Change (IPCC) report is-sued a ‘red alert’for humanity, noting climate change to be one of the most severe challenges facing human societies for decades and potentially centuries to come. Scientists are warning that we have entered a new ‘geological epoch’, named the ‘Anthropocene’, in which human activity, especial-ly the release of carbon dioxide into the atmosphere through fossil-based pollution, is transforming the stability of the earth system and creating knock on effects such as ice melt and methane release, which exacerbate the impacts of pollutants on the stability of the earth system.
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Date Issued: 2023

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Water-soluble phthalocyanines mediated photodynamic effect on mesothelioma cells

- Saydan, Nil, Durmus, Mahmut, Dizge, Meltem G, Yaman, Hanif, Gürek, Ayşe G, Antunes, Edith M, Nyokong, Tebello, Ahsen, Vefa

Authors: Saydan, Nil , Durmus, Mahmut , Dizge, Meltem G , Yaman, Hanif , Gürek, Ayşe G , Antunes, Edith M , Nyokong, Tebello , Ahsen, Vefa
Date: 2009
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/263480 , vital:53631 , xlink:href="https://doi.org/10.1142/S1088424609000863"
Description: The new peripherally 2-mercaptopyridine tetrasubstituted zinc phthalocyanine (2) and its quaternized derivative (3) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternized compound (3) shows excellent solubility in water, which makes it a potential photosensitizer for use in photodynamic therapy (PDT) of cancer. Fluorescence and singlet oxygen quantum yield measurements were conducted on 2-mercaptopyridine appended zinc phthalocyanines in dimethylsulphoxide (DMSO) for both the non-ionic (2) and quaternized (3) derivatives, and in aqueous media for the water-soluble complex 3. General trends are described for fluorescence and singlet oxygen quantum yields of these compounds. In this study, the cells were incubated with a novel water-soluble zinc phthalocyanine derivative (3) and thereafter the cells were illuminated using broad-band incoherent light source of various energy levels. Cytotoxicity of PDT on two pleural malign mesothelioma cell lines was determined by colorimetric proliferation assay. In addition, after PDT treatment, determination of activity matrix metalloproteinases (MMPs) were evaluated using gelatine zymography.
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Date Issued: 2009

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Water-soluble quaternized mercaptopyridine-substituted zinc-phthalocyanines

- Durmuş, Mahmut, Yaman, Hanif, Göl, Cem, Ahsen, Vefa, Nyokong, Tebello

Authors: Durmuş, Mahmut , Yaman, Hanif , Göl, Cem , Ahsen, Vefa , Nyokong, Tebello
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/247133 , vital:51549 , xlink:href="https://doi.org/10.1016/j.dyepig.2011.02.007"
Description: The synthesis and characterization of the new zinc phthalocyanine derivatives, tetra- (non-peripheral, 5) and octa-(peripheral, 6) substituted with 2-mercaptopyridine and their respective quaternized derivatives (8 and 9) are reported. Photochemical and photophysical properties of the new complexes are compared with those of the previously reported peripherally tetra-substituted complexes 7 and 10. The quaternized compounds exhibit excellent solubility in water, making them potential photosensitizers for use in photodynamic therapy (PDT) of cancer. Spectroscopic, aggregation, photophysical and photochemical properties of these complexes are also investigated and compared. Photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yield) properties of these phthalocyanine photosensitizers are very important for the assessment of these complexes as PDT agents. In this study, the effects of the position of the substituents and quaternization of the substituents on the photophysical and photochemical parameters of the zinc phthalocyanines are also reported. This study also showed that the water-soluble quaternized zinc phthalocyanines strongly bind to blood plasma proteins such as bovine serum albumin (BSA).
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Date Issued: 2011

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Wax discrimination in the Lesser Honeyguide Indicator minor

- Hepburn, H Randall

Authors: Hepburn, H Randall
Date: 2009
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/448440 , vital:74730 , https://doi.org/10.2989/OSTRICH.2009.80.2.11.838
Description: Beeswaxes consist of complex mixtures of homologous neutral lipids that vary among species of honeybees but share many compounds in common (Aichholz and Lorbeer 1999). However, the beeswaxes of subspecies of the honeybee, Apis mellifera, can only be distinguished after careful calculation of the peak elution pattern area ratios of selected compounds (Brand-Garnys and Sprenger 1988). This is of interest in an ornithological context because honeyguides (Indicatoridae) subsist in large measure on the pillage of the combs of honeybees (Friedman 1955) and their enzymic capacity to digest beeswax has been demonstrated experimentally (Friedmann and Kern 1956, Diamond and Place 1988, Downs et al. 2002). Honeyguides can utilise olfactory orientation to find beeswax (Stager 1967, Archer and Glen 1969) and can even detect and seek out the combs of honeybees stored in hives devoid of bees in darkened out-buildings (HRH pers. obs.).
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Date Issued: 2009

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Wearing your PIM: experiments with an audio enhanced PIM

- Tsegaye, Melekam, Bangay, Shaun D, Terzoli, Alfredo

Authors: Tsegaye, Melekam , Bangay, Shaun D , Terzoli, Alfredo
Date: 2004
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/432854 , vital:72904 , https://www.cs.ru.ac.za/research/g98t4414/static/papers/wpimfinal.pdf
Description: PIM systems help organise people’s lives by providing address book, schedule and task management facilities. Current PIM’s manage this information by collecting and storing it as textual data. With the advent of the wearable computer, using text only is no longer an efficient and convenient mechanism for managing personal information. A wearable computer should use data from various sensors (video, audio, location, environmental, user state) to organise personal information. In this paper we examine how audio can be used to enhance the facilities provided by text-only PIM’s and present an example implementation of an audio based wearable PIM (wPIM) that has the capability of storing and retrieving PIM information as audio recordings. The results of the user evaluation we conducted, which was carried out outside of the laboratory, suggests that users strongly accept audio as a way to manage their personal information and to augment their memory, supporting our hypothesis that audio enhances wearable personal information management.
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Date Issued: 2004

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Weaving cloths: Research design in contexts of transformation

- Lotz-Sisitka, Heila

Authors: Lotz-Sisitka, Heila
Date: 2002
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/184745 , vital:44268 , xlink:href="https://cjee.lakeheadu.ca/article/viewFile/259/136"
Description: Through storytelling, I apply methodological and epistemological reflexivity to ask questions about the way in which environmental education research is framed in transformational settings. I ask questions about the role of research teachers/supervisors in the “weaving enterprise” or the research process. Do we have the dual task of developing contextually relevant frameworks, and of making sure that these frameworks are not adopted on an “industrial scale”—in other words, as new paradigms which have the potential to narrow research possibilities? The paper concerns itself with a broader question, notably the potentially debilitating effects of mass production of research, or the globalizing of knowledge production. The story I use to raise these, and other questions for consideration by teachers/supervisors of research is a research workers story (my own), constructed between 1992 and 1996, in a context of rapid socio-political and educational transformation in South Africa (Lotz, 1996). In addition to the above, the paper opens a debate about reflexivity as research methodological rigour.
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Date Issued: 2002

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Weevil borne microbes contribute as much to the reduction of photosynthesis in water hyacinth as does herbivory

- Venter, Nic, Hill, Martin P, Hutchinson, Sarah-Leigh, Ripley, Bradford S

Authors: Venter, Nic , Hill, Martin P , Hutchinson, Sarah-Leigh , Ripley, Bradford S
Date: 2013
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/423573 , vital:72073 , xlink:href="https://doi.org/10.1016/j.biocontrol.2012.10.011"
Description: Arthropods released for weed biocontrol can have effects other than simply removing biomass and frequently decrease photosynthetic rate more than can be attributed to the mere loss of photosynthetic surface area. Some of this effect may result because biological control agents facilitate the transfer and ingress of deleterious microbes into plant tissues on which they feed. We evaluated this facilitation effect using water hyacinth (Eichhornia crassipes) and a weevil (Neochetina eichhorniae) and compared the reductions in photosynthetic rates between leaves subject to herbivory by adult weevils sterilized with 3.5% chlorine bleach, to those that were unsterilized. The results showed that weevils carried both fungi and bacteria, transferred these to leaves on which they fed, and that microbes and biomass removal contributed almost equally to the 37% decrease in photosynthetic productivity. Hence, maximising the effectiveness of using arthropods that damage leaf surfaces for biocontrol requires the presence of microorganisms that are deleterious to plants.
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Date Issued: 2013

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West African arthropods hold promise as biological control agents for an invasive tree in the Pacific Islands

- Paterson, Iain D, Paynter, Quentin, Neser, Stefan, Akpabey, Felix J, Compton, Stephen G, Orapa, W

Authors: Paterson, Iain D , Paynter, Quentin , Neser, Stefan , Akpabey, Felix J , Compton, Stephen G , Orapa, W
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/407119 , vital:70338 , xlink:href="https://hdl.handle.net/10520/EJC-639c91613"
Description: African tulip tree, Spathodea campanulata Beauv. (Bignoniaceae), is a large tree of secondary forests, forest edges and savannas that is indigenous to Central and West Africa (Bidgood 1994). It has been widely utilised as an ornamental plant due to its beautiful flowers, fast growth and relative ease of cultivation, as a shade tree in parks and coffee plantations, and as a living fencepost (Francis 1990). Naturalisation has often followed cultivation of the plant, which is now established outside of the native range in Africa (Hedberg et al. 2006), the Caribbean (Francis 1990; Labrada and Medina 2009) and many Pacific islands (Meyer 2004), including Hawaii, Papua New Guinea, Fiji, Samoa, Tonga,Vanuatu and Tahiti (Lowe et al. 2000; Dovey et al. 2004; Labrada and Medina 2009). On some of these islands it has become a destructive weed, invading indigenous forests and having a severe impact on agricultural production (Labrada and Medina 2009; Larrue et al. 2014). This has resulted in African tulip tree being recognised as one of the 100 worst alien invasive species worldwide, along with only 30 other terrestrial plants (Lowe et al. 2000).
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Date Issued: 2017

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We’re talking about semantics here: Axiological condensation in the South African parliament

- Siebörger, Ian, Adendorff, Ralph D

Authors: Siebörger, Ian , Adendorff, Ralph D
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/385389 , vital:68015 , xlink:href="https://doi.org/10.1075/fol.24.2.03sie"
Description: This article describes how procedural knowledge is produced in a meeting of the South African parliament’s Portfolio Committee on Transport, using concepts from Systemic Functional Linguistics (SFL) and Legitimation Code Theory (LCT). Members of this committee argue over whether or not to amend a draft committee report and in the process co-construct procedural norms for future committee meetings. Participants on both sides of the argument use axiological condensation, in which actions and ideas are associated with each other and charged with a particular moral or affective value ( Maton 2014 : 130) to portray their version of the procedure to be followed as morally superior to that of their opponents. They also use axiological rarefaction ( Maton 2014 : 130) to reinforce their positions by making apparent concessions to those on the other side of the argument. This is revealed through an analysis of the coupling of ideation and Appraisal ( Martin 2000 : 161) in the logogenetic unfolding of members’ talk, combined with elements of Interactional Sociolinguistics ( Gumperz 1982 ). The analysis suggests that axiological condensation and rarefaction in this meeting reflect competing visions of what it means to be ‘pro-democracy’ in post-apartheid South Africa.
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Date Issued: 2017

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What are social-ecological systems and social-ecological systems research

- Biggs, Reinette, Clements, Hayley, de Vos, Alta, Folke, Carl, Manyani, Amanda, Maciejewski, Kristine, Martin-Lopez, Berta, Preiser, Rika, Selomane, Odirilwe, Schluter, Maja

Authors: Biggs, Reinette , Clements, Hayley , de Vos, Alta , Folke, Carl , Manyani, Amanda , Maciejewski, Kristine , Martin-Lopez, Berta , Preiser, Rika , Selomane, Odirilwe , Schluter, Maja
Date: 2021
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/433900 , vital:73008 , ISBN 9781000401516 , https://library.oapen.org/handle/20.500.12657/49560
Description: The period since the Second World War has been marked by rapid and accelerating changes to many aspects of human society and the environment (Clark, Crutzen, and Schellnhuber 2004; Steffen et al. 2011; Steffen et al. 2015a). There is accumulating evidence and rising concern about the potential consequences these changes hold for key Earth system processes at a global scale, and human well-being and prosperity into the future (Krausmann et al. 2013; Steffen et al. 2015b). The Anthropocene, as this new era of extensive human impact on the Earth has come to be known (Crutzen 2006), manifests in a closely intertwined set of social and ecological changes. Technological advances, increasing human population, rising levels of wealth and consumption, and the institutional arrangements we have developed to govern our economies and societies interplay with one another, and drastically affect the Earth’s climate, biological diversity, fresh-water and biogeochemical flows, and levels of novel pollutants in the environment (Steffen et al. 2015a). These environmental changes, in turn, contribute to increasingly frequent and severe droughts (Dai 2013; Trenberth et al. 2014), floods (Milly et al. 2002; Nicholls 2004), heatwaves (Guo et al. 2018; Oliver et al. 2018) and the emergence of novel pathogens such as SARS-CoV-2 (Everard et al. 2020; O ’Callaghan-Gordo and Antò 2020; Schmeller, Courchamp, and Killeen 2020) that can lead to massive societal disruption and hardship, especially among the poor (Wheeler and Von Braun 2013; Barbier and Hochard 2018).
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Date Issued: 2021

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What future subordinates will value in their leaders

- Cox, Andrea, Amos, Trevor L, Baxter, Jeremy

Authors: Cox, Andrea , Amos, Trevor L , Baxter, Jeremy
Date: 2008
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/270992 , vital:54499 , xlink:href="https://hdl.handle.net/10520/EJC51031"
Description: Leaders should not randomly choose a leadership style. To be effective, leaders need to ensure that their leadership style is congruent with what subordinates value. The focus of this study is on what the future South African graduate workforce will value in a leader. The female and male respondents in this study emphasise similar leadership values, indicating that there is no distinct set of competencies that will be valued separately by males and females. The same was found for respondents of different cultures, namely African, Coloured, Indian, White and other. With respect to both gender and culture, the respondents emphasise a mixture of African and Western leadership values. This supports the idea that to be effective in South Africa, leaders need to understand the prevailing national cultural values before simply applying ''foreign'' leadership models and theories based upon cultural values found in the West. This research finds that irrespective of gender and culture in the South African workplace, to be effective, leaders need to be loyal and inspirational, have vision and integrity and must be open and honest with their subordinates. Leaders should avoid being autocratic, strict, religious, ritualistic and traditional. They should also avoid using consensus and perceived external control.
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Date Issued: 2008

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What's rotten in the state of South African journalism? media freedom and regulation

- Joseph, Natasha

Authors: Joseph, Natasha
Date: 2012
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/454999 , vital:75394 , https://hdl.handle.net/10520/EJC134119
Description: Earlier this year, I was invited to talk about the right to freedom of ex-pression as part of Rhodes University's annual Human Rights Week, which coincides with South Africa's Human Rights Day. It was suggest-ed that I might want to discuss the Protection of State Information Bill, the ominous Media Appeals Tribunal, or both. Perhaps I could have done those things - the bill and the tribunal are harrowing threats to our work as journalists, and to South Africans' freedom of access to information.
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Date Issued: 2012

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What's wrong with Walden Two?

- Tabensky, Pedro

Authors: Tabensky, Pedro
Date: 2009
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/305791 , vital:58612 , xlink:href="https://hdl.handle.net/10520/EJC96066"
Description: Despite being eminently forgettable from the literary point of view, B. F. Skinner's novel, Walden Two, provides us with an excellent opportunity, not so much to show what is wrong with mainstream accounts of free will, as Robert Kane thinks, but rather to explore another key and importantly neglected condition for genuine agency; namely, that properly lived human lives are those that are and must continue to be vulnerable to unforseable reversals, as Aldous Huxley speculates in his Brave New World. In short, I argue, perhaps scandalously, that one of the central conditions for genuine agency is that our lives are and must continue to be, to a large extent, out of our personal control. The promise of too much personal control, not too little (as Kane thinks), is what is wrong with Skinner's social utopia.
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Date Issued: 2009

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What’s in a conference theme?: Some reflections on critical realist research and its emergence in Africa over a period of 20+ years

- Lotz-Sisitka, Heila

Authors: Lotz-Sisitka, Heila
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/370739 , vital:66372 , xlink:href="https://doi.org/10.1080/14767430.2023.2146923"
Description: In keeping with the 2021 IACR Conference theme (Re) Envisaging Emancipatory Research, Science and Practice, this paper reviews over fifty instances of critical realist research in Africa which have sought to establish emancipatory research praxis by using critical realism to underlabour a range of applied studies in a diversity of disciplines and countries. The initiators of this research have been drawn to critical realism for several reasons, most notably its return to ontology, its interest in transformed, transformative praxis, and its potential for addressing knowledge and experiences exclusions. The paper ends with a reflection on ‘What's in a Conference Theme', returning to the earlier 2012 IACR conference hosted in Africa, and the 2021 conference’s focus on emancipatory research. It argues both for the deepening of conversations between critical realism and Africana Critical Theory; and for the grounding of these conversations in the voices and power of the people in our communities
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Date Issued: 2022

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What’s in a name? An analysis of the West Nggela (Solomon Islands) fish taxonomy

- Aswani, Shankar

Authors: Aswani, Shankar
Date: 1998
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/440074 , vital:73733
Description: Accurate knowledge about the behaviour, biology and ecology of organisms comprising marine fisheries is a vital prerequisite for their management. Before beginning any study on local knowledge of marine fauna, a working knowledge of their local names must be obtained. Moreover, a great deal of local knowledge can often emerge in the very process of obtaining names (Ruddle, 1994). A detailed treatment of the local naming system of West Nggela marine fauna is given in this paper.
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Date Issued: 1998

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When English meets isiXhosa in the clause: An exploration into the grammar of code-switching

- Simango, Silvester R

Authors: Simango, Silvester R
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/469300 , vital:77230 , https://doi.org/10.2989/16073614.2011.633361
Description: The phenomenon of code-switching accords linguists the opportunity to study the interaction between two distinct grammatical systems. The contact languages may have different specifications for corresponding lexical items; and a likely outcome of utilising two linguistic systems in the same speech event is the creation of a ‘new grammar’ in which some lexemes exhibit loss of certain abstract features. Using Myers-Scotton's (1993b, 2002, inter alia) Matrix Language Frame and the 4-M model, this study examines naturally-occurring isiXhosa-English data, collected from Rhodes University students in Grahamstown. The study shows that in bilingual speech some English transitive verbs lose their typical subcategorisation features such that they have to be ‘retransitivised’ by isiXhosa affixes. The paper argues that code-switching data can provide insights into the nature of lexical entries across languages as well as the patterns of grammatical convergence which result from language contact.
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Date Issued: 2011

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When I Was Young

- Hall, Ron F

Authors: Hall, Ron F
Date: 1999
Subjects: To be catalogued
Language: English
Type: text , poem
Identifier: http://hdl.handle.net/10962/469061 , vital:77156 , ISBN 0028-4459 , https://journals.co.za/doi/epdf/10.10520/AJA00284459_522
Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
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Date Issued: 1999

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