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Analyzing Microsporidia sp. MB from sequence to biology: comprehensive exploration of the genome, protein structures, and functions through extensive bioinformatics analysis

- Ang'ang'o, Lilian Mbaisi

Authors: Ang'ang'o, Lilian Mbaisi
Date: 2024-10-11
Subjects: Microsporidia , Whole genome sequencing , Proteins Structure , Symbiont , Malaria Prevention , Vector control
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/466480 , vital:76734 , DOI https://doi.org/10.21504/10962/466480
Description: Microsporidia are spore-forming intracellular organisms classified as the earliest divergent group within the Fungi kingdom. Microsporidia have been found widely affecting different hosts, including both vertebrates and invertebrates. The pathogenicity of microsporidia depends on their species and the host species they infect. Due to their obligate intracellular nature, microsporidia have extensively evolved. This is illustrated by their highly variable genome sizes and gene content. Being minimalist eukaryotes, the microsporidia genome is often associated with extreme gene reduction and compaction. However, these interesting microorganisms retain particular genes that help them acquire specific host nutrients, thereby relying heavily on their host for survival and proliferation. The mode of sexual reproduction of microsporidia has not been well-studied. Harnessing microsporidia in the laboratory is often a challenge, however, the advances in computational tools have made it cheaper and quicker to accurately predict and annotate these organisms to understand their mechanism of infection. Understanding the protein structure and function of these unique organisms is the baseline for providing insights into their biology and survival in their respective hosts. Microsporidia genomes contain a large proportion of hypothetical proteins of which their functions are not described. Vittaforma corneae ATCC 50505 was used as a model to highlight the functions and structure of these otherwise unknown proteins. A systematic annotation pipeline employing exhaustive computational tools was devised to carefully annotate the hypothetical proteins of V. corneae, aiming to characterize their structure and function.The genome of the novel microsporidian, Microsporidia sp. MB, a Plasmodium-transmission-blocking symbiont isolated from Anopheles mosquitoes in Sub-Saharan Africa, was sequenced, assembled, and annotated. The genome was found to contain over 2000 putative genes spanning its 5.9 Mb size and contained minimal repeats. Comparative phylogenomic analysis of Microsporidia sp. MB grouped this symbiont within the Enterocytozoonida (clade IV) microsporidia, clustering with its closest relative – V. corneae. Using robust computational techniques, prediction and characterization of the putative proteins of Microsporidia sp. MB was conducted. The decay of several proteins in the glycolytic pathway is one unique characteristic associated with microsporidia. The proteins retained or lost often vary across the microsporidian taxon. This study highlights the retention of most of the proteins involved in the glycolytic pathway in Microsporidia sp. MB. The available genome dataset of Microsporidia sp. MB was further used to infer its mode of sexual reproduction. The symbiont appears to have several meiotic-related gene orthologs, suggesting that it is capable of sexual reproduction. These findings describe the basic biology of Microsporidia sp. MB and provide a basis for future Next-Generation Sequencing, RNA sequencing experiments ultimately informing the application of this microorganism as a biological malaria control tool. , Thesis (PhD) -- Faculty of Science, Biochemistry, Microbiology and Bioinformatics, 2024
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Date Issued: 2024-10-11

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Togetherness, care and exclusion: adolescents’ experiences of living with a disabled sibling in a South African context

- Foote, Tamlyn Lou-Ann

Authors: Foote, Tamlyn Lou-Ann
Date: 2024-10-11
Subjects: Siblings of people with disabilities South Africa , Interpretative phenomenological analysis , Sibilings Family relationships , Sibilings Psychological aspects , South Africa Social conditions
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/466995 , vital:76805 , DOI https://doi.org/10.21504/10962/466995
Description: The importance of the sibling relationship in an individual’s life has been established, and various aspects of siblingship have been studied. Recently researchers have begun to explore what it means to be a sibling and how siblingship is embodied. Where disability is present in the siblingship, however, there is very little literature, particularly in the Global South. This cross-cultural, cross-language, Interpretative Phenomenological study explores how isiXhosa speaking adolescent non-disabled people, living in a socio-economically disadvantaged context in South Africa, experience their lives in relation to their disabled sibling. Through the use of semi-structured interviews and photo-production with 9 isi-xhosa speaking adolescents from a disadvantaged socio-economic context in South Africa, three master themes emerged. Firstly, non-disabled siblings (NDSs) experienced togetherness in their relationships with their disabled brothers/sisters. In their experiences of togetherness, where reciprocity was prominent, they felt a sense of we-ness. In these instances, disability did not play a central role in their relationships. Secondly, NDSs living in disadvantaged socio-economic contexts experienced care in different ways. Some experienced wanting to care and some experienced having to care for their disabled brother or sister. Where care was voluntary it was experienced as an act of love, contributing to their self-esteem or a family value. Where care was experienced as obligatory, NDSs felt lonely and unsupported, and this contributed to ambivalent feelings toward their disabled sibling. Finally, NDSs experienced themselves as outsiders. Experiences of being an outsider sometimes occurred because of their socio-economic status, and sometimes because of experienced stigma related to their sibling’s disability. In both instances this contributed to feelings of inadequacy and exclusion. To overcome these feelings, NDSs focused on becoming successful, wealthy or famous. These findings have important implications in terms of how NDSs may be supported. Furthermore, this study has important methodological implications for using Interpretative Phenomenological Analysis in a cross-cultural, cross-language context. , Thesis (PhD) -- Faculty of Humanities, Psychology, 2024
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Date Issued: 2024-10-11

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The spiritual space of Mubende Hill in Uganda: rethinking “awaka w’ensi aw’omweyimirize, Maama Nakayima” as a symbol of ritual and spiritual performance

- Nalukenge, Claire

Authors: Nalukenge, Claire
Date: 2024-10-11
Subjects: Mubende (Uganda) , Rites and ceremonies Uganda Mubende , Spiritual practice , Ritual objects and ceremonial , Ritual in art , Spirituality in art
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/467050 , vital:76810 , DOI https://doi.org/10.21504/10962/467050
Description: This doctoral dissertation in art history investigates the dynamic relationships between ritual objects, rituals, spiritual performances, and their representations in specific cultural contexts. The main research question is: How do the ritual objects at Mubende Hill shape and communicate the meanings of the rituals, considering their performative contexts and embodied interactions? This thesis examines the ritual objects at the spiritual space of Mubende Hill in Uganda, which have various meanings and associations for different groups of people. It critically analyses how related objects are interpreted and represented by select Ugandan contemporary artists, including the 2019 history students of Margaret Trowell of Industrial and Fine Arts and the Uganda Museum. The difference between the above components is that the spiritual space, the artists, and the students represent objects as animate, whereas the Museum represents objects as obsolete. The spiritual space of Mubende Hill is a living space where people engage with ritual objects such as calabashes, clay pots, bowls, milk containers, and coffee beans in performative ways. Some of these objects are placed in various partitions of the sacred Omweyimirize tree at the spiritual space, and the objects become efficacious when engaged with through spiritual and ritual performance. In contrast, the Uganda Museum exhibits objects as inanimate, static, and enclosed in glass compartments. As such, the objects are rendered inactive. I examine the way the museum exhibits, frames, and labels these objects, and how this shifts people’s relationships with ritual objects. In contrast, I also analyze how selected Ugandan contemporary artists and the 2019 history students represent similar objects through their artistic practices, thereby opening up the meaning of these objects. This thesis addresses the critical need for a comprehensive reading and representation of objects within their living social and cultural contexts, a focus often overshadowed by museums. In trying to grapple with questions of representations of objects, I employed qualitative research methodologies, including extensive fieldwork, analysis of primary and secondary sources, participant observation, interviews, and photographic documentation The primary information was gathered from individuals at the spiritual space of Mubende Hill, Uganda, specifically the ritual specialists and the Balyammere, select contemporary Ugandan artists, and final year 2019 art history students from the Makerere Art School and select individuals from the Uganda museum. By comparing objects within their original contexts to decontextualized objects in museums and artistic and scholarly representations of objects, I analyze various art historical approaches to objects that grapple with issues of object representation, functionality, purpose, performance, and the movement of objects. I utilize this analysis of objects to critique colonial and contemporary neo-colonial approaches to ritual objects and develop decolonial understandings of objects that are embedded in personal experiences, stories, and narratives of text accompanied with visuals from the Balyammere’s object-ritual and spiritual performances. The study argues that ritual objects possess active agency, extending beyond mere aesthetic appreciation, and they are intertwined within their performative spiritual and cultural contexts. Analyzing these objects and their roles in rituals and spiritual performances allows us to deeply comprehend their meanings and significances as embedded in cultural, spiritual, and social fabrics. The study emphasizes a need for art histories that prioritize African-based scholars at the forefront of knowledge production and appreciate diverse, non-Eurocentric perspectives, suggesting a multidisciplinary approach to understanding art. A deeper understanding of the relationship between objects, rituals, and spiritual performances cannot only expand the knowledge in art history but also suggest alternatives to conventional object perspectives and practices, arguing for a comprehensive, culturally sensitive, and inclusive approach to understanding objects and art within their performative contexts. , Thesis (PhD) -- Faculty of Humanities, Fine Art, 2024
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Date Issued: 2024-10-11

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Meerkat polarimetric observations of Pictor A

- Andati, Lexy Acherwa Livoyi

Authors: Andati, Lexy Acherwa Livoyi
Date: 2024-10-11
Subjects: Polarimetry , MeerKAT , Radio astronomy , Radio galaxies , Cosmic magnetic fields , Pictor A
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/466896 , vital:76796 , DOI https://doi.org/10.21504/10962/466896
Description: Pictor A is one of the brightest and closest radio galaxies in the Southern Hemisphere, offering a unique opportunity for in-depth studies of the astrophysics of radio galaxies and their interactions with their environments. Many multi-wavelength studies of this source have been done. However, the most comprehensive radio frequency study of Pictor A’s morphological components was conducted by Perley et al. (1997) using the Very Large Array (VLA) located in the Northern Hemisphere. To date, that work remains the most detailed study of Pictor A. In this thesis, we conducted a spectropolarimetric study of Pictor A using new L-band data obtained in 2019 from the high-sensitivity MeerKAT telescope, which provides the deepest and most sensitive data of this source at a continuous and finely sampled frequency coverage in the L-band. Thus, due to Pictor A’s proximity, high luminosity, and the MeerKAT’s high sensitivity, the data delivers a unique dataset for our study of the magnetic field structure of Pictor A and allows for a detailed study of the source’s morphological structures. We presented the steps taken during our calibration and data reduction, leading to polarimetryready images. During the first phase of calibration, excision of data corrupted by instrumental effects and radio frequency interference (RFI) resulted in only 50% useable data. Pictor A’s exceptionally bright western hotspot introduced significant artefacts in our images, mitigated in the second calibration phase through direction-dependent calibration. The calibrated data resulted in a multi-frequency synthesis (MFS) Stokes I image of Pictor A at 7.5′′ in resolution with an offsource RMS noise of ∼22 𝜇Jy/beam. The off-source noise in the Stokes Q and U sub-band images ranged between 95 – 278 𝜇Jy/beam and 41 – 233 𝜇Jy/beam, respectively. Additionally, we briefly highlighted the effects of RFI in the L-band on polarimetry, particularly the considerable loss of 𝜆2 coverage of ∼50%. All the calibration recipes used for this work were made available in this thesis. Using Pictor A’s data as a testbed, we introduced a Python-based tool, Smops, developed during the calibration stages of our work. Smops was designed for an intermediate post-processing step. It interpolates input sub-band model FITS images (such as those produced by WSClean) into finely channelized sub-band model FITS images, thereby generating model images at a higher frequency resolution. Smops reduces the need to generate model images with numerous sub-bands, which is computationally intensive and time-consuming. A higher resolution in frequency of the models facilitates more efficient model subtraction during self-calibration. We then presented the total intensity features of Pictor A, which the calibrated data reveals. We confirmed the presence of Pictor A’s radio jet extending from its core to the western hotspot. Notably, this feature, faint and barely visible in previous radio images, is now distinctly observed. The counterjet remains undetectable. Furthermore, we demonstrated the coexistence of radio emission, which is expected to align with previously observed X-ray diffuse emission. This observation confirmed the inverse Compton origin of Pictor A’s lobe emission. Employing the RM-synthesis technique for the spectropolarimetric study of Pictor A, we identified a relatively consistent rotation measure (RM) across its lobes, with an average RM of 48.06 ± 10.19 rad m−2 for the entire source. However, the eastern lobe displayed a wider RM dispersion than the western lobe. Moreover, our study affirmed the depolarisation asymmetry previously observed between the western and eastern lobes of Pictor A, where the eastern lobe exhibited significantly more depolarisation than its western counterpart. Most lines-of-sight across Pictor A displayed single-peaked Faraday spectra, indicating a single Faraday rotating screen. However, we also noted that several lines-of-sight (∼23%) showed more than one Faraday peak. An investigation into the ii possible causes of the multiple observed peaks using QU-fitting suggested that there is a possibility of a Faraday thick structure or multiple Faraday components along these paths. Furthermore, we estimated a Galactic RM contribution towards Pictor A of 23.57 ± 10.87 rad m−2. We concluded that while our Galaxy may contribute to the mean RM for this source, it cannot explain smallscale fluctuations, which suggests that some fraction of the observed rotation measures could result from some inter-galactic medium, X-ray gas near the shock boundary region (the sheath), or other unknown intervening material. We introduced Scrappy, a Python-based tool tailored for processing lines-of-sight data. Scrappy yields RM-synthesis diagnostic data products such as the data associated with each line-of-sight, and their corresponding plots in 𝜙-space (e.g. cleaned and dirty Faraday spectra and RMTF), and 𝜆2-space (e.g. the fractional polarisation, and Stokes Q and U ). Scrappy further avails a Bash-based pipeline, showrunner.sh, that processes input sub-band Stokes images, automatically selects usable sub-bands, stacks images into Stokes cubes, generates lines-of-sight, processes their corresponding data, and produces diagnostic plots. Additionally, it creates per-pixel maps of fractional polarisation, RM, polarisation angle, peak FDF, and linear polarised intensity. The pipeline ensures reproducibility. To visualise the diagnostic plots from Scrappy, we developed PolarVis, a simple web-based tool that enables the visualisation of diagnostic plots associated with each available line-of-sight, thus facilitating the quick exploration of interesting lines-of-sight in regions across this source. This tool facilitates the visualisation of polarisation behaviour for specific lines-of-sight, enabling quick identification of interesting regions of the source. Furthermore, its interactivity promotes the exploration of line-of-sight data. Availing data to the public with this tool permits validation or comparison of results from varying techniques, hence fostering a sense of transparency. As a result, the 2389 lines-of-sight of Pictor A are presented using PolarVis and are available at https://pica.ratt.center. , Thesis (PhD) -- Faculty of Science, Physics and Electronics, 2024
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Date Issued: 2024-10-11

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MeerKAT: a journey from commissioning to science

- Hugo, Benjamin Vorster

Authors: Hugo, Benjamin Vorster
Date: 2024-10-11
Subjects: MeerKAT , Interferometry , Ionosphere , Pulsars
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/466871 , vital:76794 , DOI https://doi.org/10.21504/10962/466871
Description: This dissertation presents a collection of work completed for the South African Radio Astronomy Observatory in characterizing calibrator fields PKS B1934-638, PKS B0407-65 and 3C286, the development of a facet-based multi-direction peeling scheme for the CUBICAL calibration framework and incorporation into an end-to-end containerized data reduction framework, a study of a transitional millisecond pulsar candidate, and characterization of baseline dependent archiving tooling for MeerKAT. Our long term studies of PKS B1934-638, PKS B0407-65 indicate that these bandpass and flux calibrators are stable over multiple years. We also find that, especially at low frequencies in the UHF band, the population of sources surrounding these stellar Gigahertz Peaked Sources (GPS) can contribute to errors two to three orders of magnitude above desired bandpass calibration solution stability, if left unmodeled. We derive new new full sky models of these fields, currently in use by the MeerKAT Science Data Processor. We characterize the MeerKAT feed alignment using the refraction-driven linearly polarized thermal light from the Moon in order to derive a new model for the linear polarization of the stable quasar 3C286 down to 544 MHz. Part of this work includes characterization of ionospheric corrections using the International Global Navigation Satelite System Service and direct measurement of total electron content above the MeerKAT site using interchange data from the South African TrigNET service. We find that current commonly-employed techniques achieve corrections to ionospheric Faraday rotation no better than 1 rad m􀀀2. This is the main limitation on the accuracy of polarimetric observation using the MeerKAT array. We find that 3C286 intrinsically depolarizes at frequencies below 1 GHz, with an associated non-linear increase in the intrinsic source rotation measure. We present an improvement to workflows using the CUBICAL calibration framework, developed at Rhodes University. Modern radio interferometers presents a significant challenge to calibrate, often necessitating memory and computeintensive direction-dependent calibration towards many directions in order to improve the fidelity of radio images in order to meet scientific goals. We developed a framework to simplify the model prediction aspect of these direction-dependent calibration workflows using targeted faceting. Using our scheme users use models derived from the DDFACET imaging package and only need to provide lattices to mark regions of sky to which direction-dependent calibration solutions need to be solved for. This simplifies a laborious multi-step process in traditional calibration packages that need to be executed per direction. The approach is compared to an image-space corrective regime and incorporated into the VERMEERKAT end-to-end calibration framework for MeerKAT data. The improved direction-dependent calibration techniques were then applied in an analysis of the transitional millisecond pulsar candidate CXOU J110926.4-650224. The link between accreting binary systems (where emission is dominated by the synchrotron emission of relativistic jets from thermo-nuclear reaction onto the Neutron Star surface by the infalling matter) and binary radio pulsars is currently elusive. This is due to the lack of a large population of such transitional systems — only three confirmed transitional systems are known at the time of writing. It is thought that infalling matter effectively quenches the radio pulsar mechanism. Our candidate was found to be variable in the optical and the X-ray, with transitions between low, high and flaring states lasting anywhere from a tens of seconds to tens of minutes, seen in archival observations spanning nearly three decades. For the first time we detect low level synchrotron emission (_ 50 mJy beam􀀀1) coincident with this system using MeerKAT, including a flare within minutes of a flare detected in X-ray using the XMM-Newton observatory. Our analysis indicate that there is no clear anti-correlated behaviour between radio and X-ray state transitions in this system, unlike other candidate systems—indicating that such transitional systems may not exhibit homogenous behaviour. This suggests that the processes driving the X-ray mode-switching in this system are not directly linked to the processes responsible for emitting radio synchrotron radiation. Finally, we consider the problem of MeerKAT data archiving. We present a qualification analysis, using MeerKAT data, of the Rhodes University baseline-dependent archiving package XOVA, which can be used to compress and archive MeerKAT data in interchange standard-compliant format. The data rates from interferometric array radio telescopes, such as MeerKAT, grow as the square of the number of antennas in such an array. For the sake of reproducibility and future reanalysis it is important to archive calibrated visibility products. The degree to which calibrated visibility products can be compressed, by averaging, depends on the amount of smearing that can be tolerated at a fixed distance from the center of the images synthesized from these visibility products. This is, traditionally, set by the longest spacing in the interferometric array, with all other spacings averaged to the same integration and channelization as the longest spacing. We find that, using baseline-dependent averaging techniques – where averaging intervals are set per interferometric spacing – we can achieve space savings an order of magnitude better than traditional averaging approaches, with no appreciable loss of image fidelity when compared to traditional averaging approaches. , Thesis (PhD) -- Faculty of Science, Faculty of Science, Physics and Electronics, 2024
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Date Issued: 2024-10-11

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A social realist account of the way smallholder farmers exercised their agency in the adoption of climate-smart agriculture practices in degraded landscapes in Machubeni, Eastern Cape, South Africa

- Mbengo, Idah

Authors: Mbengo, Idah
Date: 2024-10-11
Subjects: Climate-smart agriculture , Climatic changes South Africa , Climate change adaptation South Africa Eastern Cape , Social realism , Farms, Small South Africa Eastern Cape
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/466884 , vital:76795 , DOI https://doi.org/10.21504/10962/466884
Description: Over the last two decades, climate-smart agriculture (CSA) has been promoted as a way to address the challenges of climate change for smallholder farmers' productivity, food security and livelihoods. Given concerns about climate change, many studies have contributed to developing an understanding of resilience building and crop and livestock systems adaptation. Despite evidence of the effectiveness of CSA practices, several studies report on their limited uptake by farmers involved in various projects. The reasons for low rates of adoption remain unclear. In this context, the study on which this thesis is based drew on Bhaskar’s critical realism and Archer’s social realism to explore the way smallholder farmers in five villages in a rural area in South Africa were enabled and constrained as they exercised their agency in a project intended to introduce them to CSA practices. The study was not about adaptation and resilience building per se but rather, following Bhaskar and Archer, sought to identify the generative mechanisms enabling and constraining the adoption of CSA practices. Bhaskar’s critical realism posits a view of reality as layered. The topmost layer of reality is the Empirical. This consists of observations and experiences of the world around us and is understood to be relative. The second layer, the Actual, is the layer of events from which observations and experiences located at the level of the Empirical emerge. Events at the level of the Actual and experiences and observations at the level of the Empirical emerge from an interplay of mechanisms at the deepest layer of reality identified by Bhaskar, as the Real. In positing a layered ontology, critical realism allows for the relativity of experiences and observations while, at the same time, acknowledging the reality of structures and mechanisms, which cannot be directly observed but nonetheless exist. Archer’s work on agency accords personal powers and properties (PEPs) to all individuals. Although all individuals have the power to act in relation to the world around them, they are nonetheless conditioned by their previous histories and experiences as they do so. As individuals set about exercising their agency, they are enabled or constrained by structures and mechanisms in two domains at the level of the Real which are understood to possess their own powers and properties: the structural domain and the cultural domain. In addition to drawing on Archer’s conceptualisation of the interaction between agency, structure and culture, the study also uses her “morphogenetic framework” which allows for the identification of ‘whose conceptual shifts are responsible for which structural changes, when, where and under what conditions’ (Archer, 1998: 361) and for understanding change as a series of never-ending cycles. The first phase of Archer’s morphogenetic framework, entitled T1, involves social and cultural conditioning. In the study, T1 was understood to be the time until 2017 when the project on which the study focused began. The second phase, T2 to T3, is the phase of social and cultural interaction as agents exercise their PEPs to pursue concerns they have identified for themselves and encounter structural emergent powers and properties (SEPs) and cultural emergent powers and properties (CEPs) of mechanisms located in the domains of structure and culture as they do so. The final phase of the framework, T4, allows for an evaluation of what has changed and what has not changed. My claim is that the uptake of CSA practices is impacted by different forms of consciousness or ways of experiencing the world, which is the result of the social and cultural conditioning of different groups involved in the project at T1, and clashes between them. The use of the framework drawing on critical realism and social realism allowed for the identification of these different forms of consciousness in different social groups (project facilitators, elderly farmers and the youth). These different forms of consciousness were understood to condition the agency of the three groups and thus enable or constrain the introduction of CSA practices and how they were taken up. Elderly women in the project had been conditioned to be caregivers and to see their roles tending kitchen gardens as part of their identity. This consciousness led to the uptake of CSA practices in their home gardens. By contrast, young people engaged with the project shared a very different way of experiencing the world. They were better educated and had been socialised into using social media and watching films on electronic devices from a young age. As a result, they valued the role of money in accessing consumer goods and the good life and thus valued paid employment rather than working on the land to provide subsistence. This led to a limited uptake of CSA practices. It is envisaged that insights from the study will offer new ways of understanding what might otherwise be seen as resistance to adopting CSA practices as well as new ways of engaging with different groups of agents involved in projects in the future. The study demonstrates the explanatory power of critical realism and social realism to analyse a climate change adaptation project. , Thesis (PhD) -- Faculty of Science, Environmental Science, 2024
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Date Issued: 2024-10-11

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Activist radio and the struggle to empower audiences: a case study of the Zimbabwean history

- Chaunza, Garikai

Authors: Chaunza, Garikai
Date: 2024-10-11
Subjects: Activism Zimbabwe , Radio broadcasting Political aspects Zimbabwe , Authoritarianism Zimbabwe , Democracy Zimbabwe , Zimbabwe Social conditions , Zimbabwe Politics and government
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/466907 , vital:76797 , DOI https://doi.org/10.21504/10962/466907
Description: This study is grounded in my 18-year career in journalism in Zimbabwe. This journey began in January 2006 at the Zimbabwe Broadcasting Corporation (ZBC), where I started as a news reporter. In June 2008, I left ZBC and transitioned to freelance roles, including work at Radio Voice of the People (VOP), which broadcasted from South Africa using Radio Netherlands' transmitters in Madagascar. Simultaneously, I corresponded for The Zimbabwean Newspaper, edited in the UK, printed in Johannesburg, South Africa, and distributed to Zimbabwe, Radio Netherlands, Free Speech Radio News (USA), KPFA Pacifica Foundation Radio (USA), and DW (German). More recently, my work has expanded into the digital domain, contributing to New Zimbabwe, an online newspaper for the Zimbabwean diaspora in the UK, before transitioning to Community Radio Harare. Throughout my 18-year career as a media practitioner and journalist in Zimbabwe, I faced constant state-sanctioned interference, and even physical violence, while executing my responsibilities. Initially, at the Zimbabwe Broadcasting Corporation (ZBC), several colleagues and I, including our news editor, were politically victimised and ultimately fired for covering opposition political players and human rights activists. Later, when I was operating outside state-established media outlets, I experienced a series of threats, intimidation, arrests and detentions by state security. This was also true during my six-year tenure as the chairperson of the Media Institute of Southern Africa's Harare advocacy committee. This experience underscored the importance of studying the history of media activism in this country, focusing on the role that activists have played sustaining the alternative media despite intimidation by the state. I am convinced of the importance documenting their experiences, capturing their contribution to the creation of alternative communication platforms for marginalised audiences. In exploring the literature I discovered that the traditions of activist media, in which I have been involved myself, are rooted in a much older history that can be traced back to pre-independent Zimbabwe. At that time, colonial authorities also restricted media freedoms and employed violence against pro-democracy activities, referred to as nationalists. I decided, for the purpose of this study, to delve into this pre-history of media activism in Zimbabwe, focusing on radio in particular. I wished to gain insight into the way media activists have, over time, sustained their involvement in the traditions of radio practice that can empower marginalised communities. I was conscious that the continued survival of activist radio in this country has often been arduous, with activists facing harassment, arrests, and detentions by authoritarian administrations resisting the opening up of democratic spaces. I wished to trace this history of resistance from its origins in the mid-twentieth century to the time of my own involvement in such radio in the 21st century. In particular, I hoped to identify shared normative foundations as well as shared practices for the implementation of these ideals. Chapter One of the study explores the history of activist radio from the mid-20th century to the present, identifying five distinct phases in Zimbabwe's socio-political history and illustrating how each phase shaped the media landscape. Building on this, Chapter Two establishes a theoretical framework underpinning the values and principles driving media activists to create people-oriented radio projects to empower marginalized communities. Chapter Three delves into the documented history of activist radio within the broader context of media activism in Zimbabwe, engaging with each of the five key moments detailed in Chapter One. Chapter Four outlines the research plan for the empirical fieldwork and discusses its implementation. In Chapter Five, I present interviews with radio activists from the 1970s' nationalist radio and those involved in the pirate radio tradition that re-emerged at the turn of the millennium, sharing their practical experiences. Chapter Six focuses on interviews with community radio advocates, detailing their involvement in radio activism during the first decade of the millennium. Finally, Chapter Seven examines the activities of community radio practitioners, exploring their experiences with unlicensed radio projects and highlighting their creative endeavours. , Thesis (PhD) -- Faculty of Humanities, Journalism and Media Studies, 2024
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Date Issued: 2024-10-11

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Border crossing, collecting, gravitating: small narratives of three ordinary collectors in the Chinese diaspora in South Africa since the late 1980s

- Grobbelaar, Binjun

Authors: Grobbelaar, Binjun
Date: 2024-10-11
Subjects: Chinese diaspora , Art Collectors and collecting South Africa , Autobiography in art , Art History , Knowledge, Sociology of , Proximity
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/467039 , vital:76809 , DOI https://doi.org/10.21504/10962/467039
Description: Shifting away from the conventional viewpoint that confines art collecting predominantly to established structures like art institutions, markets, and exclusive collector networks, a trajectory historically influenced by Western collecting traditions and museology, this thesis takes a radical turn by delving into the small narratives of three ordinary Chinese collectors, namely Shengkai Wu, Yiyuan Yang and Shudi Li, who immigrated to South Africa since the late 1980s. The focus on Chinese collectors and migration resonates with my positionality as a recent Chinese immigrant in South Africa and aligns with Boaventura de Sousa Santos’s approach to proximity in knowledge-making, which emphasises ‘knowing with’ and ‘walking alongside’ the subjects of study. The selected immigrant collectors were chosen based on their current low-to-middle economic status in South Africa. These three individuals have decades of living and artcollecting experience in the country, having held professional backgrounds in China prior to their immigration. The number of collectors was determined through an in-depth qualitative biographical research method, taking into account the niche field of art collecting and the relatively small Chinese population within the broader South African demographic. It approaches collecting as a method of pursuing clues and explores it as a socio-cultural practice by collaging the biographies of three ordinary collectors as micro-histories. Details of these ordinary lives are entangled with the lives of objects that traverse China and South Africa. The use of non-official data, at times fragmented and partially obscured, is employed to craft a narrative that weaves together diverse and complex perspectives. The aim of this thesis is to attempt to shift from elite collecting narratives to a more diverse understanding of the global circulation and appropriation of art and cultural objects in relation to grassroots migration. This shift is explored through the unique insights derived from recovering the personal narratives of ordinary immigrant collectors and their associated objects in overlooked geographical locations and states of transformation within the context of China– Africa relations. I engage China–Africa relations within the framework Global South, seeks to address the limitations of describing the multi-dimensional interweaving of low-profile individual and objecthood, unofficial and official, historical and ephemeral relationships in the burgeoning field of China-Africa relations. The investigation unfolds through two interconnected aspects embedded in the development of each collector’s biography. Firstly, it delves into how the collecting practices of these three Chinese collectors are interwoven with their experiences in both China and South Africa. Secondly, it examines the agencies of the collectors and the relationships they establish with the objects they collect. I approach these collectors as curators of their autobiographical exhibitions in the process of preliminary data collection and subsequent thematic and object-oriented interviews. Through the analysis of collectors’ oral, visual and written narratives, as well as the biographies of objects, this PhD thesis in Art History uncovers a multilayered influx of crossways of knowledge-making by the collectors on the ground. Inspired by practical material re-ordering and personal interests, these collectors engage in configuring the border-crossing process within the Chinese diaspora in South Africa. Recurring narratives of critical socialist experiences in Maoist China are linked to their suppressed agency and subsequent recovery through emigration to South Africa. They negotiate a complex diasporic terrain marked by engaging with socialist philately materials, persistently gravitating towards China. Concurrently, they transcend conventional nation-state framework, accentuating the convergent aesthetic qualities inherent in transnational artefacts and community-based art practices. The collectors’ engagement with exported Chinese “specialised arts and crafts”, and unconventional artefacts, such as philately materials, creates a bottom-up fresh interpretation of what constitutes collecting Chinese art in the context of South Africa. Fragments of British colonial history on the Rand, Chinese semi-colonial history, and contemporary printmaking in both China and South Africa, embedded in tangible material artefacts and in intangible visual connection, become visible through their logics of collecting and affective approach from the bottom up. Highlighting the often-overlooked Chinese agency in the creation of these objects, this research illustrates how individual mobility between China and Africa can contribute to the nuanced role of aesthetics through collecting, redefining what is visible and meaningful in the context of the Chinese diaspora and art collecting in South Africa. Specifically, discourses on the border poetics of Zheng He, colonial postcards and notices on the Rand, visual connection in printmaking, and Chinese semi-colonial artefacts of a converged “Chinese–British” aesthetic and a controversial Tang blue-and-white dish are instances where ordinary Chinese collectors in the Global South strategically mobilise collecting as a means to migrate towards an alternative politics of hope, as conceptualised by Chiara Brambilla. This hope presents a “strategic Southerness,” cultivates an “alter-geopolitics of knowledge” (Simbao 2017) that, pushing against the often-dominant representation of spectacle within the structured frameworks of art institutions, markets and networks of elite collectors. I argue that these emerging themes and objects in the collectors’ narratives represent a grounded, localised knowledge-making from below, unfolding practices underpinned by the material conditions of ordinary collectors of art and material culture in the Global South, aspects that have not been given adequate attention in history. In the process of encountering, reassembling, and appropriating these material objects and associating people in South Africa, I argue that collecting becomes not only an act of diasporic agency in constructing memories of the past, but also offers insight into the complex Chinese diaspora within the dynamics of a rising Chinese presence in Africa. On the one hand, these ordinary collectors employ collecting as an act of resistance against the aftermath of political turmoil and the epistemological inequality imposed on grassroots communities. Their emergence has contributed to transforming the residual colonial culture of the “othering” in the landscape of art collecting in South Africa. On the other hand, their agency intersects with Chinese diasporic nationalism, which lingers in the tension between internalised Eurocentric exploitation and romanticised appreciation and cultural preservation, a question that awaits for further investigation. , Thesis (PhD) -- Faculty of Humanities, Fine Art, 2024
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Date Issued: 2024-10-11

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A house accursed: reconsidering Sophocles’ sisters, Antigone & Ismene

- Fox, Peta Ann, Sophocles

Authors: Fox, Peta Ann , Sophocles
Date: 2024-10-11
Subjects: Ismene (Greek mythology) , Antigone (Greek mythological figure) , Electra (Greek mythological figure) , Chrysothemis , Greek tragedy , Sisters in literature
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/467028 , vital:76808 , DOI https://doi.org/10.21504/10962/467028
Description: Traditionally, Ismene’s refusal to help Antigone bury their brother in Sophocles’ Antigone tends to be regarded only in relation to Antigone’s own remarkable bravery. Antigone exists on the heroic level, Ismene on the ordinary; Antigone is courageous, Ismene is timid and submissive; Antigone is an idealist and an individualist, Ismene is convention and herd-bound. Ismene is, in many ways, presented as the antithesis of Antigone and Sophocles does indeed make use of her character as a foil to Antigone, but this thesis will argue that the relation between the two sisters is far more complicated than a dichotomous contrast between ‘extraordinary heroine’ and ‘average woman’. Like Antigone, Ismene is very much a character in her own right, and her emotions, motivations and impulses are every bit as realised and compelling as Antigone’s own. Both sisters have been deeply affected by the tragic misfortunes of their family, but their sad history affects each sister quite differently. Whereas Antigone’s instinctive reaction to Creon’s edict is a furious determination not to tolerate any further dishonour, Ismene’s equally instinctive reaction is to avoid the pattern of self-destructive inwardness that has plagued their family for generations. By offering a comprehensive re-examination of the key passages that have informed our critical reception of Ismene and the nature of her relationship with Antigone, this study aims to disrupt the established, and largely prejudiced, reading of Ismene as a model of feminine timidity and submission. Although Ismene is certainly no grand tragic heroine, titling the theoretical focus away from the death-oriented extremism of Antigone towards a more balanced consideration of the so-called ‘weaker sister’ not only allows for new insights into the nature of Sophoclean tragedy, but also challenges the very basis on which Ismene has so often been dismissed in favour of her more intrepid sister: the pervasive assumption that Sophocles has only given us one sister who is willing to risk her life for a principle. , Thesis (PhD) -- Faculty of Humanities, School of Languages and Literatures, 2024
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Date Issued: 2024-10-11

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Biology and management of the fruit piercing moth Serrodes partita in citrus orchards

- Mushore, Tapiwa Gift

Authors: Mushore, Tapiwa Gift
Date: 2024-10-11
Subjects: Baculoviruses , Moths Monitoring , Pests Control , Insect traps , Citrus Diseases and pests South Africa Kat River Valley , Catapult moth
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/466792 , vital:76779 , DOI https://doi.org/10.21504/10962/466792
Description: The fruit-piercing moth, Serrodes partita (Fabricius) (Lepidoptera: Erebidae), is a polyphagous, multivoltine pest of citrus. This insect has a distinct geographical separation between its larval and adult stages, each with different feeding patterns. During the larval stage, it primarily acts as a forest defoliator, feeding mostly on Jacket plum, Pappea capensis Eckl. & Zeyh. (Sapindaceae). In contrast, the adult stage of this moth feeds on both tropical and subtropical fruit, including citrus and can cause serious economic losses. The adult moth uses its sclerotised proboscis to pierce the skin of ripening or ripe fruit, from which it extracts the juice. This piercing action initiates a fermentation process within the fruit, attracting other secondary-feeding moths, commonly referred to as fruit-sucking moths. As a result of the feeding activity, the affected fruit eventually rot, drop to the ground, and become unsuitable for the market. Serrodes partita exhibits an outbreak life strategy, reoccurring every 5 to 10 years. In South Africa's Eastern Cape Province, specifically in the Upper Kat River Valley, citrus growers have expressed concerns about the impact of this moth on soft citrus (Satsumas and Clementines). This raises the possibility of a shift in the population dynamics of S. partita, where these occurrences become more frequent and less sporadic. Such a trend poses a significant threat to fruit arboriculture in the Eastern Cape region. Currently, there are limited management strategies available for managing fruit-piecing moths. The use of pesticides is not a feasible option for ripe or nearly ripe fruit, and is ineffective against the adult moth. Alternative control methods, such as orchard netting and light barriers, either come with high costs or are impractical for large-scale citrus production. Given the limited range of management options, combined with the moth's tendency for sudden outbreaks, citrus growers find themselves without effective means to manage this pest. The objective of this study was, therefore, to investigate the biology of S. partita and explore various control options to effectively manage this pest. Research focused on the biology and laboratory rearing of larval stages of S. partita. The flight behaviour, feeding patterns, and preferences of adult S. partita within citrus orchards were also explored. The aim was to elucidate key fundamental aspects, including whether the same population frequents a particular orchard, and if infestations within orchards exhibit a specific direction. Lure type and lure presentation method trials were conducted to determine the most effective lure and trap design. Seasonal monitoring of S. partita in soft citrus orchards was conducted over three years to determine its outbreak status in the Committee’s Drift area and the role of weather variables in the activity of the moth. Damage assessments were also conducted alongside monitoring to determine the level of damage inflicted by S. partita. Natural enemies associated with S. partita were explored to determine the prevalence and causes of mortality in late instars during laboratory rearing. Rearing S. partita on an artificial diet was unsuccessful despite several modifications. The moth, however, completed its entire life cycle on its natural host, P. capensis in the laboratory. The total life cycle from egg to adult took 80.7 ± 3.6 days, the larval stage lasted 52.3 ± 2.8 days, and the pupal stage lasted 25.8 ± 3.6 days at 21°C. The investigation into the biology of S. partita also brought attention to the most susceptible stages of its growth, with high mortality rates recorded among neonates and late instars. The findings of the study revealed directional patterns of moth infestations, with higher numbers observed at the orchard's periphery leading towards natural vegetation. This raises the prospect of using sacrificial rows on the edge of a citrus orchard to concentrate moth feeding damage during outbreak years. Using a mark and recapture technique, the study showed that a relatively small proportion (4.5 %) of moths tended to revisit the same orchard. The moths strongly preferred damaged fruit (85 %) over undamaged fruit. Visible damage (rotting symptoms) typically became apparent within 3 to 5 days. Satsumas had a higher number of feeding scars (2.1) than Clementines (1.08), highlighting their susceptibility. The study also established that, on average, pierced soft citrus fruit takes about four days to display symptoms of decay. Synthetic proprietary Australian lures were ineffective at attracting the moth, whereas fresh bananas proved to be a successful lure. Furthermore, the addition of both Agar and Super absorbent polymer showed promise as thickening agents to enhance the longevity of fresh bananas in traps. The effectiveness of various trap designs was compared, including the funnel trap, delta trap, bucket trap, and circular trap, in capturing fruit-feeding moths. The funnel trap performed best as it captured the most moths, followed by the delta trap, Lynfield trap and disc trap, respectively. Additionally, an electronic enhancement to the funnel trap, incorporating a zapper element, improved efficiency. However, efforts to exploit both visual and olfactory cues through the inclusion of an Ultraviolet (UV) light component did not improve its effectiveness. No extensive outbreaks were recorded during the study; however, population variations of S. partita populations were recorded. Annual trends showed two population peaks, with the first peak recorded from December to March, while the second peak was recorded from April to July. The activity of the moths also differed across different months, with the highest peaks recorded in May, while no moths were recorded from August to November. Both cultivar type and farm location did not influence the occurrence of the moth. Meanwhile cumulative weather parameters (rainfall, temperature and humidity) from the four months prior to occurrence influenced the activity of S. partita. Temperature determined the timing of the outbreak, while rainfall determined the magnitude of the outbreak. Damage assessment showed very low fruit damage by S. partita throughout the monitoring period. Varying levels of infestation by a tachinid fly, 4 % and 35 %, were recorded for 2021 and 2022, respectively. The tachinid parasitoid could not be identified at the species level. A novel baculovirus, tentatively classified as S. partita NPV (SepaNPV), was identified as the larval mortality causative agent. This study enhanced our understanding of S. partita's biology and population dynamics, providing valuable insights for developing effective management strategies against this economically impactful citrus pest. Future research should focus on refining control measures and addressing the challenges of the adult moth's elusive nature. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
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Date Issued: 2024-10-11

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