Showing items 41 - 60 of 17726

A scoping review on problematic Internet use and Substance Use Disorder among men

  • Authors: Adolph, Miché Tania
  • Date: 2024-10-11
  • Subjects: Internet addiction , Substance abuse , Men Mental health , Scoping review protocol , Compulsive behavior Sex differences
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/465788 , vital:76653
  • Description: Problematic Internet Use (PIU) and Substance Use Disorder (SUD) interact in complex ways that influence the current mental health landscape. Concurrently, the advent of the digital era has presented new difficulties, one of which is the emergence of problematic internet use as a significant issue that negatively impacts mental health. The increasing popularity of internet use has led to an increasing number of reports highlighting the potential negative consequences of overuse, such as substance use. Thus, the study aimed to synthesise literature on problematic internet use and substance use disorder, including the way in which they affect men, given that prior research has predominantly focused on women. The methods employed follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) which is largely based on a PRISMA statement and checklist, the JBI methodological guidance, and other approaches for undertaking scoping reviews. A total of 16 studies were eligible for final review, and the themes identified from the reviewed studies were obtained using Braun and Clarke’s thematic analysis. An analysis of the articles showed a large focus on gender differences in addiction patterns, vulnerability to problematic internet use across age groups, associations between substance use and behavioural addictions, problematic internet use and mental health disorders, the psychological consequences of problematic internet use and substance use disorders, and the various risk factors associated with the development of problematic internet use and substance use disorder. A clear understanding and conceptualisation of this behavioural addiction is vital, including the development and utilisation of appropriate and validated diagnostic and screening tools to measure its presence and, in turn, address it as an emerging mental health disorder. Focus should be given to the assessment of problematic internet use by distinguishing the two different forms, namely the generalised and specific forms of problematic internet use. Additionally, given that there were very few to no qualitative studies conducted on the topic of problematic internet use, much less addressing the possible association with substance use disorder, an assessment of the individual’s experience, especially that of men, is lacking. Future research could therefore aim to incorporate more qualitative studies to address the above. Further research is also needed to clarify the nature of the relationship between problematic internet use and substance use disorder for the purpose of establishing possible causality, including the neurobiological substrates involved. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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  • Date Issued: 2024-10-11

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

  • 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

A social realist analysis of the professional identity formation of lecturers emerging from completing professional development at a South African research-intensive university

  • Authors: Adams, Anthea
  • Date: 2024-10-11
  • Subjects: Identity (Psychology) in education , Academic development , Staff development , Social realism , Critical realism , Scholarship of teaching and learning , Education, Higher South Africa
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/466372 , vital:76722 , DOI https://doi.org/10.21504/10962/466372
  • Description: This doctoral study is part of a Department of Higher Education and Training (DHET) capacity development project, Phakamisa. Using Margaret Archer's Social Realism as a substantive theory and methodological tool and Roy Bhaskar's Critical Realism as a meta-theory, I was able to identify and explain the interplay between the structural, cultural and agential mechanisms within a professional development course that enabled or constrained the emergence of lecturers' professional academic identities. My research participants are fourteen lecturers who completed the Postgraduate Diploma in Higher Education (PGDip HE) at Rhodes University between 2007 and 2017. Social Realism's explanatory methodologies, analytical dualism, and the morphogenetic cycle allowed me to provide causal explanations and account for the historicity of the emergence of lecturers' professional academic identities as teachers. A qualitative research design involving case study research allowed me to search for generative mechanisms to understand and explain the conditioning influence of often unobservable phenomena and underlying mechanisms in developing lecturers' identities as teachers in a research-intensive university. As strong social actors imbued with power and material resources, university leadership should consider the constraining influence of contextual conditions, such as the hegemony of disciplinary research versus research in the Scholarship of Teaching and Learning (SoTL). The socio-cultural (S-C) interactions of the fourteen lecturers (agents) signal the possibilities for structural, cultural and agential morphogenesis when agents choose to exercise their agency, i.e., their personal emergent properties (PEPs) to mediate prevalent structural and cultural emergent properties (SEPs and CEPs) enabling or constraining their personal projects. Lecturers' personal projects are the courses of action they intentionally engage in as they strive to establish sustainable yet evolving practices as teachers in their disciplines. This thesis shows that exercising their PEPs involves subjective reflexivity and transforming from primary agents to corporate agents due to collective action and alliances with like-minded peers and colleagues to shape the teaching and learning agenda in their respective departments and the broader higher education context. Triple morphogenesis of lecturers' agency occurred through their realisation as social actors. It signified the formation of their professional identities as teachers and how they uniquely embodied and enacted their teacher roles. , Hierdie doktorale studie is deel van 'n Departement van Hoër Onderwys en Opleiding (DHOO) kapasiteitsontwikkelingsprojek, naamlik Phakamisa. Deur gebruik te maak van Margaret Archer se Sosiale Realisme ("Social Realism") as 'n substantiewe teorie en metodologiese instrument, en Roy Bhaskar se Kritiese Realisme ("Critical Realism") as 'n metateorie, was ek in staat om die wisselwerking tussen die strukturele, kulturele en agentiese meganismes binne 'n professionele ontwikkelingskursus te identifiseer en te verduidelik wat die ontstaan van dosente se professionele akademiese identiteite moontlik gemaak of beperk het. Die deelnemers in my navorsing is veertien dosente wat die Nagraadse Diploma in Hoër Onderwys (NGDip HO) aan Rhodes Universiteit tussen 2007 en 2017 voltooi het. Sosiale Realisme se verklarende metodologieë, analitiese dualisme en die morfogenetiese siklus het my toegelaat om oorsaaklike verklarings te verskaf en die historisiteit van die ontstaan van dosente se professionele akademiese identiteite as onderwysers te verantwoord. ’n Kwalitatiewe navorsingsontwerp wat gevallestudienavorsing behels het, het my toegelaat om na generatiewe meganismes te soek om die kondisionerende invloed van dikwels onwaarneembare verskynsels en onderliggende meganismes in die ontwikkeling van dosente se identiteit as onderwysers in ’n navorsingsintensiewe universiteit te verstaan en te verduidelik. As sterk sosiale rolspelers deurdrenk met mag en materiële hulpbronne, behoort universiteitsleierskap die beperkende invloed van kontekstuele toestande, soos die hegemonie van dissiplinêre navorsing versus navorsing in die Akademieskap van Onderrig en Leer (AvOL, of in Engels "Scholarship of Teaching and Learning", afgekort na SoTL) in ag te neem. Die sosiokulturele (S-K) interaksie van die veertien dosente (agente) dui op die moontlikhede vir strukturele, kulturele en agentiale morfogenese wanneer agente doelbewus kies om hul agentskap uit te oefen, dit wil sê hul persoonlike ontluikende eienskappe (in Engels "personal emergent properties", afgekort na PEPs) om heersende strukturele en kulturele ontluikende eienskappe te bemiddel (in Engels "cultural emergent properties", afgekort na CEPs) wat hul persoonlike projekte moontlik maak of beperk. Dosente se persoonlike projekte is die aksies wat hulle doelbewus aangepak het terwyl hulle daarna gestreef het om volhoubare dog ontwikkelende praktyke as onderwysers in hul dissiplines te vestig. Hierdie tesis dui aan dat die uitoefening van hul persoonlike ontluikende eienskappe ("PEPs") behels subjektiewe refleksiwiteit en transformasie van primêre agente na korporatiewe agente as gevolg van kollektiewe optrede en alliansies met eendersdenkende eweknieë en kollegas om die onderrigen leeragenda in hul onderskeie departemente en die breër hoëronderwyskonteks te beïnvloed. Drievoudige morfogenese van dosente se agentskap het plaasgevind deur hul verwesenliking as sosiale rolspelers. Dit het die vorming van hul professionele identiteite as onderwysers aangedui en die unieke manier hoe hulle hul onderwyserrolle interpreteer en uitleef. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning, 2024
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  • Date Issued: 2024-10-11

A sociological study of women’s lived experience of menopause and understanding of menstruation in Mthatha and Makhanda, Eastern Cape Province

  • Authors: Makalima, Buthanani Vuyokazi
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466210 , vital:76707
  • Description: This qualitative study explored different sociocultural factors that influence and inform women’s menopause experience and perceptions. The aim of the study was to investigate the cultural beliefs about menstruation and menopause, with a focus on embodied experiences of menopause, as well as the perceptions of the transition from menstruation to menopause. Six in-depth interviews were conducted with women in their 60s and 70s in the Eastern Cape Province: four in-depth interviews were conducted in Umtata/Mthatha and two in Makhanda. Data was analysed thematically. A key study finding is that women’s definition and experience of menopause is significantly influenced by their sociocultural context. This also shapes their experience of menopause, and in the case of the women in this study, menopause is experienced as a natural process. Regardless of the participants’ acceptance of menopause, some women still need to be equipped with information on severe menopause symptoms, what they mean, and how they can be treated or managed. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

A study exploring women’s experiences, knowledge, attitudes, and perceptions of fibroids in Diepsloot, South Africa

  • Authors: Nwanamidwa, Moreblessing Itani
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466071 , vital:76682
  • Description: This study is an exploration of women’s experiences, knowledge, attitudes, and perceptions of fibroids. It is underpinned by social constructionism and the common-sense model of self- regulation theoretical frameworks. Eight in-depth semi-structured interviews were conducted with women in Diepsloot, South Africa. The study aimed to include diverse perspectives, thus participants included women who consulted biomedical and cultural practitioners or both. The findings of the research reveal that women’s experiences with fibroids are complex because of the many decisions they have to make about the diagnosis and treatment options and the multiple, and sometimes intersecting temporary disruptions, caused by fibroids. Furthermore, the low levels of awareness about fibroids and the prevailing culture of silence surrounding women’s reproductive health have negative consequences for women living with fibroids as this can result in delayed diagnosis and treatment. The findings highlight the importance of raising awareness about fibroids in communities such as Diepsloot where awareness initiatives are insufficient, given the high prevalence of fibroids among reproductive age black women. , Thesis (MA) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

A systematic revision of Aprionyx Barnard, an endemic South African genus of Leptophlebiidae (Ephemeroptera)

  • Authors: Ferreira, Ina Susan
  • Date: 2024-10-11
  • Subjects: Biogeography , Leptophlebiidae Geographical distribution , Leptophlebiidae Morphology , Leptophlebiidae Phylogeny , Leptophlebiidae Classification
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/466770 , vital:76777 , DOI https://doi.org/10.21504/10962/466770
  • Description: Aprionyx Barnard, 1940 is the most speciose genus of Leptophlebiidae in South Africa and endemic to the southern region. Like the other African Leptophlebiidae, Aprionyx has received limited research. The earliest described Aprionyx species were based only on adults that were then placed in Atalophlebia Eaton, 1881. The first descriptions of nymphs were contributed by Barnard (1932), with the smooth claws of the nymphs being the distinctive feature that allowed him to create Aprionyx for all of the South African species placed in Atalophlebia at that time. This research aimed to improve knowledge of Aprionyx species by revising its molecular and morphological systematics. Molecular phylogenetic analysis of the COI, 16S and 28S genes generated a species tree illustrating the species’ relationships within Aprionyx. Species delimitation analyses (bPTP and GMYC methods) were generally congruent with the molecular phylogenetic species composition. The phylogeny identified up to ten potentially new species, a substantial increase in the species diversity of Aprionyx. Review of the descriptions of the eight named Aprionyx species resulted in major nomenclatural changes concerning A. tabularis (Eaton, 1884), A. phoeocera (Lestage, 1924) stat. rev. and A. intermedius Barnard, 1932 n. syn. With the redescriptions of all currently known species, the nymph of A. rubicundus Barnard, 1932 was described for the first time. An identification key to the species of Aprionyx was compiled from newly recognized descriptive characteristics and, for the first time, includes both imagos and nymphs. Molecular and morphological phylogenetic analyses recovered Aprionyx as monophyletic, although this was poorly supported morphologically. The phylogenies were topologically congruent and identified two clear geographically separated clades, a western and eastern Aprionyx group. Molecularly, morphologically and geographically, these two clades were recovered as two clearly distinct groups within the genus. The analyses further identified three lineages in Aprionyx: rubicundus, pellucidulus and eastern Aprionyx. The estimated age of Aprionyx indicated that initial diversification occurred during the Cretaceous (approximately 100 ma). Aprionyx peterseni (Lestage, 1924) was shown as the oldest of the analysed species, and the main drivers to species diversification were possibly the glacial cycles of the Quaternary period, through the mechanism of river anastomosis during fluctuating sea levels. Further research is needed to strengthen the support for the hypothesis identified in this study, but a substantial foundation has been laid by this work for future research, conservation and environmental decision-making. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
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  • Date Issued: 2024-10-11

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

  • 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

An analysis of the precarious livelihoods of Zimbabwean migrants in the informal economy in Makhanda, South Africa

  • Authors: Nderere, Nompumelelo Agnes
  • Date: 2024-10-11
  • Subjects: Precarious employment , Informal sector (Economics) South Africa Makhanda , Foreign workers, Zimbabwean South Africa Makhanda , Sustainable livelihood , Gig economy
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466262 , vital:76712
  • Description: The movement of people across borders is a complex phenomenon that has far-reaching social, political, and economic implications. In recent years, Zimbabwean migrants have become increasingly visible in the informal economy across South Africa. Through qualitative data collection methods, this study sought to broaden our understanding of the precarious livelihoods of Zimbabwean migrants working in the informal economy in South Africa. This study examined Zimbabwean migrants in the informal economy in Makhanda, Eastern Cape in South Africa. Underpinned by the Sustainable Livelihoods Approach (SLA) as the theoretical anchor, this thesis offers a comprehensive examination of not only the challenges but also the opportunities faced and presented to Zimbabwean migrants in the informal economy in Makhanda. The Sustainable Livelihoods Approach was used as a framework to guide the analysis aimed at understanding the precarious livelihoods of Zimbabwean migrants working in the informal economy in terms of the vulnerability context they find themselves in, the assets they use, the organizations or institutions that affect their activities and the results they get out of their efforts in the informal economy. Data was collected from a sample of 10 participants, consisting of 4 self-employed participants and 6 “employed” in the informal economy. Through in-depth interviews and thematic analysis, this thesis examined the strategies that the migrants adopt to cope with the challenges they face and the impact that these strategies have on their livelihoods. The findings suggest that working in the informal economy evolves as a sustainable livelihood strategy, which depends on external support for it to flourish. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

An assessment of the status of psylloid species (Hemiptera: Psylloidea) as potential pests of commercial citrus in southern Africa: implications for pest management

  • Authors: Moagi, Raynold
  • Date: 2024-10-11
  • Subjects: Citrus Diseases and pests South Africa , Candidatus Liberibacter , Psylloidea , Polymerase chain reaction , Insect trapping Equipment and supplies , Pests Control
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/464417 , vital:76509
  • Description: Psylloids (Hemiptera: Psylloidea), constitute a group of plant sap-sucking insects, some of which are economically significant pests in different ecosystems due to their potential to transmit Gram-negative bacteria, such as the Candidatus Liberibacter species. The African citrus triozid (ACT), Trioza erytreae (Del Guercio), which transmits African citrus greening and the Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, which transmits Asian citrus greening are significant threats to citrus. Asian citrus psyllid poses a global economic threat due to its ability to vector “Candidatus Liberibacter asiaticus” (CLas), which can rapidly kill citrus trees. However, both ACP and CLas are currently not present in southern Africa but are present in East and West Africa. In the Afrotropical region, 71 triozid species are known to occur and approximately 41 described Diaphorina species in southern Africa. Currently, two indigenous Diaphorina species, Diaphorina punctulata and Diaphorina zebrana have been documented to feed on citrus. There is a significant knowledge gap regarding the ecological roles of other indigenous psylloid species occurring within the citrus environments. Therefore, this study aimed to: (i) determine the diversity and community structure of psylloid species in citrus environments, and (ii) their host ranges through DNA analysis of gut contents to determine if they fed on citrus. Field surveys were carried out across 12 distinct commercial citrus environments across Limpopo and Mpumalanga provinces between 2022 and 2023. Psylloids were collected using yellow sticky traps and an insect sweep-net. Collected psylloid specimens were preserved in 70% ethanol vials and identified to the lowest possible taxonomic level (i.e. genus or species) using both published and unpublished dichotomous identification keys. Furthermore, citrus leaf samples were collected from the same plants on which psylloids were found in the orchards. Genomic DNA (gDNA) was extracted from both leaf and psylloid samples using two different DNA extraction methods. To confirm if citrus DNA could be detected in the psylloid guts, all leaf gDNA samples were initially amplified using the rbcLaF/R primer pair, targeting a 530-bp region of the chloroplast rbcL gene through the polymerase chain reaction (PCR). Lastly, gut content analysis was performed on 11 psylloid species using the same primer pair through PCR to detect citrus DNA. A total of 4,900 psylloids belonging to five families (i.e. Aphalaridae, Carsidaridae, Liviidae, Psyllidae and Triozidae), 19 genera and 47 species, were collected in citrus environments. More psylloids were recorded in Limpopo (3,754) than in Mpumalanga (1,146). The most abundant species were Pauropsylla trichaeta (1,680), followed by Diaphorina punctulata (466), Trioza erytreae (426), Diaphorina virgata (371), Euryconus sp. (358), Cacopsylla sp. (311), Retroacizzia mopanei (263), Acizzia russellae-group (240), Acizzia sp.3 (216) and Acizzia sp.2 (140). Yellow sticky traps captured 3,265 psylloids in citrus orchards, while an insect sweep-net collected 1,635 psylloids (477 from citrus orchards and 1,158 from adjacent natural vegetation). Data from the insect sweep-net revealed that 22 psylloid species were recorded on citrus. In comparison, nine psylloid species were found on Vachellia spp. and unidentified plant species separately, whereas six, three and two psylloid species were recorded on marula, Ficus sp. and mopane, respectively. The abundance, richness and community structure of psylloids differed significantly between the collection methods, provinces and among plant species. The rbcLaF/R primer pair amplified all citrus leaf gDNA samples, producing amplicons of the targeted 530-bp size. The PCR analysis of 11 psylloid species showed that the rbcLaF/R primer pair amplified plant DNA, with PCR-amplified plant DNA samples producing amplicons between 500-bp and 750-bp in the gut contents of five psyllid species: Diaphorina punctulata, Diaphorina virgata, Diaphorina zebrana, Euryconus sp. and Trioza erytreae. However, the targeted 530-bp plant DNA region was only amplified from the gut contents of Euryconus sp. and Diaphorina punctulata. This study documented psylloid diversity and community structure within commercial citrus environments. The findings indicate that the community of psylloids was diverse in citrus environments, with yellow sticky traps being more effective in monitoring different psyllid species within these environments. Furthermore, the PCR analysis detected citrus DNA in the gut contents of Euryconus sp. and Diaphorina punctulata, suggesting that they could be nibbling on citrus when their specific or main host-plants adjacent to citrus orchards are depleted. However, these insects do not lay their eggs or complete their life cycle on citrus, further confirming that citrus is not their host-plant. Thus, further studies, including Sanger sequencing of PCR-amplified plant DNA, are recommended to confirm the ingested plant species, and host-specific testing including infection trials needs to be conducted. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
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  • Date Issued: 2024-10-11

An evaluation study of the climate change adaptation plans for a provincial conservation authority in South Africa

  • Authors: Van den Berg-McGregor, Eleanor Charmell
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/461930 , vital:76252
  • Description: While there are natural changes in climate over time, the climate change phenomenon of global warming that the Earth is currently experiencing is human-induced. The impact of human-induced climate change has led to unprecedented global warming and has become evident as there have been increases in the frequency and intensity of extreme weather events such as inter alia, heatwaves, droughts and floods. This climate change trajectory poses a risk to the Earth’s ability to continue providing sustainable ecosystem services necessary to sustain life on Earth. Therefore, considering the risks and impacts of climate change, there is a need to strengthen the global response to the threat of climate change, and hence, there is a need for climate change adaptation (CCA). Some benefits of CCA include the reduction of risks to nature and people, biodiversity conservation, food security, livelihoods and human well-being. Through a CCA lens within the biodiversity and conservation sector, underpinned by Resilience Theory, this research study sets out to identify and evaluate the CCA plans of a provincial conservation authority. By reviewing the current literature for CCA, the insights gained allowed for the emergence of key characteristics for good CCA in the biodiversity and conservation sector, and the evaluation of CapeNature’s (a provincial conservation authority situated in the Westen Cape of South Africa) CCA plans against these key characteristics that emerged for CCA and resilience planning in protected areas and ecosystems. Qualitative data was gathered via focus groups and individual semi-structured interviews with seven key knowledge holders of CapeNature’s CCA planning processes, plans and management approaches, and through document analysis of the entity’s CCA plans, whereafter it was evaluated against the key characteristics. Challenges towards CCA and opportunities that can be explored for CCA were identified as well. This research study has revealed that CapeNature does not have a single all-encompassing CCA plan but has various CCA approaches that consider the key characteristics necessary for good CCA. However, the entity faces various challenges regarding its intention to implement these approaches over the long term. Challenges ranged from a fragmented approach to CCA to compromised capacity and capability to implement their CCA plans over time. A recurring challenge was the lack of financial resources, and this, combined with the entity’s current inability to secure sustainable financing, was emphasised as the key factor to be addressed towards facilitating the success of the entity’s CCA plans. It also emerged that CCA approaches are interdependent and linked as in various instances, when one key CCA characteristic was compromised, it had a detrimental effect on other CCA approaches. The study concludes by making recommendations to enhance CapeNature’s CCA and resilience planning, noting that these may be of relevance to other conservation agencies as well. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
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  • Date Issued: 2024-10-11

An exploration of the influence of gender dynamics on the experience of NGO staff members in Makhanda

  • Authors: Hove, Taguma Florence
  • Date: 2024-10-11
  • Subjects: Gender inequality , Non-governmental organizations South Africa Makhanda , Black feminism , Corporate culture South Africa Makhanda , Gender stereotype , Sex role
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466139 , vital:76700
  • Description: This research explores gender dynamics within non-governmental organisations (NGOs) and examines whether, and to what extent women in the NGO sector perceive gender dynamics as playing instrumental roles in NGO organisational processes and structures. In conjunction with this, this research aims to explore the relationship between gender stereotypes and career progression. Black feminism and postcolonial feminism will be implemented as theoretical frameworks to explore how social or gender, age, race, and class interact with the organisational process of NGOs. The concepts of intersectionality and subjectivity are useful in understanding how interactions between race, class, and gender play a role in the subjective experiences of women of all backgrounds in post-apartheid South Africa. A postcolonial feminist approach focuses on the representation of African women, and allows an exploration of the knowledge of South African women within NGOs that will provide more perspectives to organisational studies. Traditional perspectives of gender stereotypes are widespread, but several respondents are indifferent to gender stereotypes while some of them feel that they are non-existent. The findings indicate that gender stereotypes continue to exist with forward movements in social progress, where progress might be stalled because of ingrained patriarchal norms, making it difficult to eradicate gender inequality. The findings from the research also suggest that there are tensions and contradictions involved when it comes to how female NGO staff members perceive gender discrimination, providing nuance to existing research. This research acknowledges the period of transition that society is in and recognises how complexities emerge. The findings capture the present state of gender identity, and applying an intersectional approach has indicated that other factors such as race, ethnicity and age take precedence. The research also recognises the importance of tracking and responding to changing societal attitudes in times of transition. Finally, the research also contributes to a broader understanding of the perceptions of gender identity and equality and ensures that discussions on patriarchy do not depend on established discussions that present reality in a stark way that does not leave space for nuance. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

An investigation into the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of Tulbaghia violacea collected from the Eastern Cape and Gauteng Province

  • Authors: Kader, Tasmeera
  • Date: 2024-10-11
  • Subjects: Tulbaghia violacea , Phytochemicals , Alliaceae Geographical distribution , Diabetes , Alzheimer's disease
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/461819 , vital:76242
  • Description: Introduction: The number of communicable and non-communicable diseases continues to rise and has become more prevalent. While drugs exist to manage and/ or treat majority of the communicable and non-communicable diseases, the rise in disease prevalence puts pressure on researchers to find new drug molecules to treat and manage these ailments. Traditional medicine refers to the knowledge, skills and practices which are based on the beliefs and experiences indigenous to cultures and is used to maintain health. Most of the research into traditional medicine focuses on the medicinal plants used. Medicinal plants are any plants in which one or more of its organs contain substances which are used for therapeutic purposes or for the synthesis of drugs. Tulbaghia violacea is a monocotyledonous genus of herbaceous perennial bulbs which is native to Africa and can be readily found throughout South Africa. It is popular for its antimicrobial, antifungal, anticoagulant, antioxidant and anticancer properties. It has been that ecological factors influence the composition and quantity of phytochemicals present in a plant. Aim of the study: The aim of the study was to investigate the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of T. violacea collected from the Eastern Cape and Gauteng Province. Methods: The leaves of T. violacea were collected from the Eastern Cape and Gauteng Province. The leaves were dried and extracted using serial maceration with solvents hexane, acetone and methanol. The resulting extracts were subjected to qualitative preliminary phytochemical analysis and a quantitative total phenol content test was carried out using gallic acid as the standard. Thin layer chromatography (TLC) was performed to identify classes of compounds present in T. violacea. xix Antioxidant activity of T. violacea was determined qualitatively using a dot-plot and quantitatively using a DPPH radical scavenging activity assay. Ascorbic acid was used as the standard. Anti-diabetic properties of T. violacea were assessed using an α- amylase inhibition assay and an α- glucosidase inhibition assay. Acarbose was used as the standard for these assays. The anti-Alzheimer properties of T. violacea leaf extracts was determined using and acetylcholinesterase (AChE) inhibition assay. Donepezil was used as the standard for this assay. The DPPH radical scavenging activity, the α- amylase inhibition assay, the α- glucosidase inhibition assay and the AChE inhibition assay was combined with linear regression to determine the IC50 values of the T. violacea extracts and the standards. Statistical analysis was conducted to determine any differences between the plant samples and the standards as well as any differences between the EC and GP sample. Results: The results of the qualitative phytochemical analysis revealed the presence of saponins, flavonoids, tannins, alkaloids, steroids, cardiac glycosides and phenolic compounds present in T. violacea collected from EC and GP. However, their presence in the samples were different based on where the plant was cultivated. The results of the total phenolic content test, revealed that the hexane, acetone and methanol extracts of T. violacea contained phenolic compounds with the highest quantity of phenolic compounds being present in the methanol extracts. Significant statistical difference in total phenolic content between the EC and GP samples were seen for the hexane and methanol extracts. The results of the TLC revealed the presence of multiple bands which confirmed the presence of multiple phytochemicals in T. violacea. All of the extracts of T. violacea from EC and GP, showed antioxidant activity using both the dot-plot and the DPPH radical scavenging activity assay. The highest DPPH radical scavenging activity was seen by the hexane extract of the EC sample of T. violacea. The results showed significant statistical difference between the DPPH radical scavenging activity of the EC and GP samples. , Thesis (Msc (Pharmacy)) -- Faculty of Pharmacy, Pharmacy, 2024
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  • Date Issued: 2024-10-11

An investigation of geospatial technologies in precision agriculture: a case study on a citrus orchard in the Eastern Cape

  • Authors: Nish, Declan Mark
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/465080 , vital:76571
  • Description: Citrus production is an input-intensive farming practice that carries a high cost of production. A multitude of both local and global factors continue to put pressure on farmers to produce enough food for local consumption as well as international exports. Despite these challenges production and exports continue to increase, fighting to meet the growing rise in global demand for citrus (Genis, 2018). Growers are continuously in search of anything that may provide them with the ‘edge’ or an advantage to overcoming some of these challenges (Jupp, 2018). One way in which these issues could be addressed is the use of precision agriculture (PA). Precision agriculture, particularly that of commercial, Unmanned Aerial Vehicle (UAV) based PA, provides growers with solutions to these issues in the form of high quality, near real-time data, and provides access and benefits from technology driven agriculture to growers at all levels (Sishodia et al. 2020). The aim of this research therefore was to investigate the potential of high resolution, multi-spectral UAV, and satellite imagery to help citrus farmers manage their inputs better, save costs and increase their yields in a sustainable manner. Supervised image classification using a support vector machine (SVM) was applied to map and classify a citrus farm in the Eastern Cape. The approach aided the identification of Phytophthora spp in the section of interest and implies that remotely sensed data can be used to detect changes in citrus health. Guidelines for applying geospatial technologies at farm level were developed to provide a framework for enabling growers to enhance data driven farm management strategies. , Thesis (MSc) -- Faculty of Science, Geography, 2024
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  • Date Issued: 2024-10-11

An investigation of the knowledge of and attitudes towards cervical cancer among female students at Rhodes University

  • Authors: Pila, Anastacia Mosima
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466267 , vital:76713
  • Description: South African and African studies on the knowledge of cervical cancer show that there is generally a limited understanding and knowledge of cervical cancer among women. It is for this reason that this qualitative study examines the knowledge of and attitudes towards cervical cancer among female students at Rhodes University, with the aim of determining whether or not this specific group of women (young and educated) has a better understanding and knowledge of cervical cancer. Semi-structured in-depth interviews were conducted with ten female RU students, and two members of staff at RU campus. Using thematic analysis, the study found that there is also a lack of understanding and knowledge of cervical cancer among the participants. Participants were mostly unaware of its causes, preventative methods, screening methods, and they did not know any cervical cancer-based organisations or initiatives in their communities. The two RU members of staff participants confirmed the latter as they stated that the Rhodes University First Thing’s First is the only organisation in Makhanda that deals with cervical cancer awareness and screening. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

Analysing the equity dimensions and governance drivers of water security challenges in Hammanskraal, City of Tshwane, South Africa

  • Authors: Mahlatsi, Malaika Lesego Samora
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/465011 , vital:76565
  • Description: South Africa is faced with a national water security challenge that is increasingly worsening due to a myriad of structural and governance factors. Over the past few years, several municipalities across the country have experience temporary loss of water access, while some have come dangerously close to Day Zero – a day when water levels of the major dams supplying water to residents would become critically low, resulting in households having no running water. But for the people of the township of Hammanskraal in the City of Tshwane metropolitan municipality, water insecurity has reached crisis point. Since 2005, the township has been battling with a chronic lack of access to safe drinking water. The water quality in Hammanskraal has been so dire that in 2019, the South African Human Rights Commission declared it unfit for human consumption and deemed it a violation of human rights. Despite this, the crisis has persisted. In 2023, Hammanskraal became the epicentre of a cholera outbreak that claimed a number of lives in several provinces across the country. Using a qualitative approach, this study analyses the equity dimensions and governance drivers of water security challenges in Hammanskraal. Through interviews with residents in Hammanskraal and government officials in the City of Tshwane metropolitan municipality and the Gauteng Provincial Government, the study explores the lived experiences of those affected by the water insecurity, as well as the governance drivers that inform the crisis. The study, using water justice theory and conflict theory/Marxism, contends that the water security challenges in Hammanskraal are driven by physical, economic and political factors. These factors have their roots in the geo-history of the township as well as contemporary responses to spatial development and water resource management by the post-apartheid government. The study finds that there are equity dimensions to the water security challenges in Hammanskraal. Contextually, the legacy of apartheid’s policy of separate and uneven development, coupled with contemporary failings of the implementation of the National Water Act, impact water access. In terms of water governance, while factors such as climate change and urbanisation are contributing determinants, the water security challenges in Hammanskraal are fundamentally the result of institutional failings that include lack of planning and investment as well as lack of infrastructure maintenance. The implications for South Africa in general is that failure to resolve water inequities and to strengthen water governance will result in the reproduction and persistence of structural inequalities. Key recommendations of the study include the expansion of the Temba Water Purification Plant, strengthening and coordination of institutions for water security, the setting of water allocation ceilings in Gauteng municipalities and investment in alternative water sources and tools for water conservation. The study also recommends further study into the extent to which water security challenges impact social unrest in South Africa. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2024
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  • Date Issued: 2024-10-11

Analysis of saprolite-hosted Rutile-Graphite deposit: a case study of Malingunde saprolite-hosted Rutile-Graphite project in Central Malawi

  • Authors: Zabula, Ansel Aliko
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/464970 , vital:76562
  • Description: The Malingunde graphite project, owned by Sovereign Metals Ltd (SML), has revealed significant potential for rutile and high-grade graphite in saprolite. This study addresses the complexity of mineral assemblages in the Malingunde area, emphasizing the coexistence of graphite and rutile. SML's exploration activities, including extensive drilling and soil sampling, have uncovered variations in associated minerals, such as muscovite, kyanite, garnets, and ilmenite. Rutile, initially discovered incidentally, has prompted further investigation, impacting the financial model of the project. This research aims to analyse the Malingunde deposit, focusing on understanding its mineralogy, formation, and potential for elements like vanadium. Geological surveys reveal the distribution of graphite in the Precambrian to lower Palaeozoic age basement complex, hosted in saprolite resulting from tropical weathering of graphitic gneisses. Exploration techniques, including remote sensing, and geophysics, are crucial in targeting graphite and rutile deposits. Ground electromagnetic surveys, airborne electromagnetic data, and GIS applications aid in identifying and quantifying mineralised areas. Geochemical analysis and metallurgical tests further contribute to understanding the ore body and processing methods. Results indicate an inverse relationship between graphite and rutile concentrations, influencing the economic viability of different regions within the project area. Correlation matrices and regression analyses reveal distinct geological conditions influencing the association of vanadium and graphite in Lifidzi and Malingunde. The study concludes with exploration potential outside the Malingunde project, highlighting regional prospects and potential byproducts like vanadium pentoxide. The ongoing metallurgical tests and pilot plant design signify the project's evolution toward production. Additionally, neighbouring licenses show potential, emphasizing the need for comprehensive research to define and quantify resources in the region. This research provides valuable insights for the mining industry, informing strategies for exploration, resource assessment, and potential byproduct utilization in similar geological settings. , Thesis (MSc) -- Faculty of Science, Geology, 2024
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  • Date Issued: 2024-10-11

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

  • 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

Application of SWAT+ model to assess the hydrology of irrigated agricultural catchments in Western Cape, South Africa

  • Authors: Mabohlo, Sakikhaya
  • Date: 2024-10-11
  • Subjects: Soil and Water Assessment Tool , Agricultural hydrology , Hydrologic models , Irrigation , Reservoirs , Water-supply, Agricultural South Africa Western Cape
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/464986 , vital:76563
  • Description: Agricultural activities can modify hydrological processes in catchments. An in-depth investigation of the impact of agriculture on hydrological processes is thus crucial for sustainable water management and utilisation planning in agricultural catchments. Hydrological models are widely used as practical tools to estimate and understand hydrological processes at various scales in catchments. However, it is often challenging to represent hydrological processes accurately in agriculture-dominated areas due to their complexity and the structural inadequacy of models. Complexities driven by agricultural developments such as reservoirs, cultivation irrigation, and water transfers are often intricate and difficult to represent in detail. The current study applied the SWAT+ hydrological model to the agriculture-dominated Twee and Leeu catchments in the Western Cape Province of South Africa. The SWAT+ model was preferred because it is versatile in representing multiple reservoirs and irrigation from multiple sources. The model application aimed to enhance the understanding of hydrological processes and the impact of agricultural water use on catchment hydrology, explore the capabilities and performance of this relatively new version of the SWAT in a complex catchment and provide baseline hydrology input for systems models that were used to formulate a water management plan for the catchment. The SWAT+ model was able to represent the significant number of reservoirs in the catchment. In some cases, small farm dams had to be lumped together to deal with the model's structural inadequacy. The model performed well in terms of observed and simulated streamflow comparison. NSE and R2 values above the standard of 0.5 were obtained for both catchments. Moreover, an NSE of 0.7 at a daily time-step simulation was obtained for the Leeu Catchment validation period, indicating a generally impressive SWAT+ performance. The model indicated that hydrological processes in the area were largely dominated by evapotranspiration, which is expected of semi-arid regions. 55% of the total water input into the Twee quaternary catchment is lost through evapotranspiration, while 22% is converted into surface runoff. Interflow and groundwater flow account for 9% and 9% of the catchment water, respectively. The remaining 5% is distributed to soil moisture and groundwater storage. For the Leeu, the model simulated a loss of 67% of the precipitation through evapotranspiration. Interflow and surface runoff were estimated to be 25% and 24%, respectively. Groundwater contribution to the stream accounts for 7%. Therefore, evapotranspiration and surface runoff are the dominant processes from a water balance perspective, whereas groundwater flow is also significant. Agricultural activities impacted the hydrological system significantly, and this is mainly attributed to the construction of numerous reservoirs and the subsequent intensive irrigation in the dry summer periods. The model simulation revealed that the reservoir and irrigation reduced the annual average streamflow by 71% in the Twee Catchment. In the Leeu Catchment, reservoirs and irrigation resulted in an annual average streamflow reduction of 77%. Therefore, agriculture has significantly altered flow patterns in the catchment, particularly downstream areas, during drier years. In conclusion, understanding of hydrological processes, reservoir and irrigation impact on catchment flow dynamics are the key outcomes that support decision-making regarding sustainable water management and utilisation planning. The broader outcomes, including spatially distributed flows and irrigation demand for different crop types, were used as baseline inputs for systems models that explored various water management options. SWAT+ thus played a crucial role in developing a water management plan for the area. Although the model exhibited some structural deficiencies in representing some catchment complexities, it fairly represented and enhanced our understanding of the hydrological dynamics of the Twee and Leeu Catchments. Additionally, the model has proven to be a versatile tool that can be applied for practical catchment water management in the agriculture-dominated catchments of South Africa. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2024
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  • Date Issued: 2024-10-11

Artificial Intelligence (AI) and blockchain technologies in advancing sustainable healthcare development in Kenya: a critique of dependency theory

  • Authors: Monethi, Tlhokomelo Brigette Rethabile
  • Date: 2024-10-11
  • Subjects: Artificial intelligence , Blockchains (Databases) , Dependency theory , Sustainable development , Health care reform Kenya
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466016 , vital:76677
  • Description: This thesis explores the transformative potential of artificial intelligence (AI) and blockchain technologies in advancing healthcare delivery in Kenya through a critique of Dependency Theory. It investigates how these technologies contribute to improving accessibility, efficiency, and quality of care—particularly in underserved regions, while also addressing the structural dependencies that limit Kenya’s healthcare autonomy. Using a qualitative methodology, this study examines five case studies—Sophie Bot, Ilara Health, Tambua Health, AfyaRekod, and PanaBIOS—to highlight both the opportunities and challenges AI and blockchain present in reducing external reliance. Although AI-powered diagnostics and blockchain-based patient data management systems have revolutionised healthcare in Kenya, these technologies remain dependent on foreign capital and expertise for their development and maintenance. The research finds that while AI and blockchain technologies offer a path to leapfrog traditional barriers in healthcare delivery, their implementation critiques traditional notions of dependency theory. Nonetheless, the thesis identifies significant ethical considerations—including digital inequality, data privacy, and AI biases—that must be addressed to ensure equitable, self-sufficient healthcare provision. This study concludes with recommendations for fostering technological autonomy in Kenya's healthcare system, focusing on building local capacity, addressing infrastructural challenges, and aligning AI and blockchain integration with ethical and socio-cultural contexts. By doing this, this research contributes to the broader discourse on technology and healthcare in developing nations, offering pathways for reducing dependency and achieving sustainable healthcare development in Kenya. , Thesis (MA) -- Faculty of Humanities, Political and International Studies, 2024
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  • Date Issued: 2024-10-11

Aspects of the sustainability of the wild honeybush industry

  • Authors: McGregor, Gillian Kathleen
  • Date: 2024-10-11
  • Subjects: Cyclopia intermedia , Renewable natural resources South Africa , Sustainability , Local ecological knowledge , Harvesting
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/464266 , vital:76493 , DOI 10.21504/10962/464266
  • Description: Honeybush products are uniquely South African, derived from plants of the fynbos genus, Cyclopia. Cyclopia intermedia is the most widespread species, distributed across 11 496 km2 of the Cape Fold Mountains, and provided the bulk of supply for the industry until 2022. While the industry is small, it is a locally significant industry affecting the livelihoods of harvesters, farmers and processors in the greater Langkloof region of the Eastern and Western Cape provinces of South Africa. The industry has evolved from a cottage one, to a commercial scale, and concerns have been raised over the sustainability of the wild resource specifically, and the industry in general. The research aimed to improve our understanding of aspects of the sustainability of the wild honeybush industry. A mixed methods design was adopted, which allowed for the inclusion of data collection approaches and analysis which tell a richer story than one with a singular modus. Four objectives were identified, which entailed: (i) mapping the resource to establish the distribution range of C. intermedia; (ii) recording of local ecological knowledge (LEK) and traditional ecological knowledge (TEK) around best practice harvesting; (iii) assessing the sustainability of harvest enterprise types through analysis of yield history and harvester loads; (iv) identifying differences between harvested and unharvested C. intermedia populations. Mapping of the resource drew on a variety of existing data sources, field mapping, GIS-based analysis, species distribution modelling and expert mapping to create a comprehensive and accurate map of the species distribution. The species is estimated to occupy a distribution range of 11 496 km2, 49% of which occurs in formally protected areas. Based on local scale mapping by experts, 100km2 is estimated to be in use for wild harvesting in the production area of the Langkloof. Information on best practice harvesting was collected through in-depth interviews with harvesters, harvest managers, processors and farmers (in the field at harvest events) and through questionnaire surveys and focus group discussions at a honeybush stakeholder workshop. In combination with harvest event surveys at which harvester practice was observed and recorded, and surveys were conducted of the harvest yield and of plants in the harvested population, the information was used to produce the first formal account of best practice for sustainable harvesting of wild honeybush. To assess the sustainability of harvest enterprises and associated harvester livelihoods, harvester managers were interviewed to create profiles of typical harvesting enterprises based on their practices and harvest yield histories. Of the three harvest enterprises considered, two showed sustained yields over time, while those of a large contract type enterprise were less sustainable with declining yields on three out of six farms. From a statistical analysis of the records it was found that the most effective team size was 10 or less harvesters in terms of livelihood sustainability. They could earn a fair livelihood (ZAR67 680.00) per annum, based on a 94 kg load per daily harvest event, sold to the processor at ZAR 5.00, for nine months of the year, working a four-day week. For a team to operate sustainably, it was found that it should consist of experienced harvesters harvesting conservatively, at intervals of at least four years, and be responsive to local environmental conditions. Detailed field surveys of C. intermedia plants at 38 sites representing harvested and unharvested populations were carried out to understand the impact of harvesting on the plants. A statistical analysis of the plant's dimensions related to the physical environment, fire and harvest history using generalised linear models revealed that while unharvested plants were slightly larger, only crown diameter and stem counts were significantly so. Seedlings were noticeably scarce at all sites, including recently burnt sites. A significant finding of the research was that in a fecundity survey, unharvested plants produced significantly more pods. The impact of this is unknown, but it has implications for management and the sustainable use of wild resources in the long term. Further understanding of the impact of harvesting came from surveys of cultivated stands of C. intermedia (different ages and harvest histories, but all harvested at three-year intervals) and surveys of a wild population, which was subjected to unregulated harvesting. For the cultivated stand: after 12 years, plants declined in all measured dimensions, while in the wild population, 45% of the plants died over a seven-year period. The surveys proved that a three-year interval or frequent, unregulated harvest is unsustainable. The research was used to produce the wild harvesting guidelines, which have become the accepted standard for the industry. It has demonstrated that under the right circumstances, harvesting of the wild C. intermedia resource is broadly sustainable. However, there needs to be informed management of the use of the resource in terms of harvest team types and their protocols, particularly with regard to harvest intervals and possible interventions to improve seed production to achieve sustainable use of the resource in social, economic and ecological terms. , Thesis (PhD) -- Faculty of Science, Geography, 2024
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  • Date Issued: 2024-10-11
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