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The In Silico Prediction of hotspot residues that contribute to the structural stability of subunit interfaces of a Picornavirus Capsid:

- Upfold, Nicole, Ross, Caroline J, Tastan Bishop, Özlem, Knox, Caroline M

  • Authors: Upfold, Nicole , Ross, Caroline J , Tastan Bishop, Özlem , Knox, Caroline M
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149970 , vital:38919 , https://doi.org/10.3390/v12040387
  • Description: The assembly of picornavirus capsids proceeds through the stepwise oligomerization of capsid protein subunits and depends on interactions between critical residues known as hotspots. Few studies have described the identification of hotspot residues at the protein subunit interfaces of the picornavirus capsid, some of which could represent novel drug targets. Using a combination of accessible web servers for hotspot prediction, we performed a comprehensive bioinformatic analysis of the hotspot residues at the intraprotomer, interprotomer and interpentamer interfaces of the Theiler’s murine encephalomyelitis virus (TMEV) capsid.
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The in vitro antiplasmodial and antiproliferative activity of new ferrocene-based α-aminocresols targeting hemozoin inhibition and DNA interaction:

- Mbaba, Mziyanda, Dingle, Laura M K, Swart, Tarryn, Cash, Devon, Laming, Dustin, de la Mare, Jo-Anne, Taylor, Dale, Hoppe, Heinrich C, Biot, Christophe, Edkins, Adrienne L, Khanye, Setshaba D

The incidence of musculoskeletal disorders and stakeholder perceptions of work challenges in South-Eastern Nigerian quarry mining industry

- Egwuonwu, Victor Afamerfuna

  • Authors: Egwuonwu, Victor Afamerfuna
  • Date: 2020
  • Subjects: Quarries and quarrying -- Health aspects -- Nigeria , Musculoskeletal system -- Diseases -- Nigeria , Miners -- Health and hygiene -- Nigeria
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/141263 , vital:37957
  • Description: Musculoskeletal disorders (MSDs) are very common among industrial labourers, leading to sick leave absence, disability and low productivity at work. MSDs have multifactorial causes, thereby making it difficult to pinpoint the extent of the contributions of the various risks regarding the mechanism of its pathophysiology. Previously, attempts were made to study regional pain symptoms in varying occupational groups, disregarding the particularities of the different workplace situations. It is important to highlight, that quantifying physical exposure factors that contribute to MSDs occurrence using quantitative approach alone could be inadequate. It is therefore imperative to incorporate qualitative approach to unmask accompanying psychosocial stressors, which are mostly explanatory variables. The study investigated the following: 12-month retrospective prevalence of MSDs, prospective incidence, risk factors and pattern of MSDs in a 6-month follow-up survey of selected quarry mineworkers, who reported MSDs complaints at the mine clinic. The study also determined the level of psychosocial stress associated with working in the mine by understanding stakeholders’ perception of work challenges, and how it influenced recurrence of MSDs. The study utilised a mixed method design with two phases: phase 1 was an initial baseline retrospective prevalence and a prospective cohort-control incidence survey. The Cultural and Psychosocial Influence on Disability (CUPID) questionnaire was translated into an Igbo-language version, cross-culturally adapted and utilized. The instrument was administered via oral interview and sought information on the following: demographic characteristics; pain in different anatomical sites and associated disability for tasks of daily living; as well as information on any change of job and reason during the study period, recent pain in different anatomical sites and associated disability for tasks of daily living; distress from common somatic symptoms; mental health status, sickness absence in the past 5-months for musculoskeletal pain. Phase 2 was a qualitative focus group discussion that engaged mine stakeholders on their perceptions of work challenges. Descriptive statistics of mean and standard deviation was utilised to analyse sociodemographic characteristics of participants. MSD incidence rates were estimated and the patterns of MSD incidence at different anatomical sites were also determined. The Cox proportional regression analyses were utilised to compare hazard ratios of MSD risks between the exposed cohorts and unexposed cohorts in the phase one incidence survey, alpha level was set at 0.05. Transcription, thematic and content analyses with the aid of Nvivo version 11 for windows was used to interpret stakeholders’ perception of work challenges. The incidence of MSD was 6.2 per 1000, with shoulder pain being the most reported complaint (40% prevalence). This was followed by back pain with the distribution of back pain presented as follows: upper back (20.37%), lower back (45.50%) and both (34.13%). All participants reported previous medical history of back, shoulder and neck pain. The relative risk ratio of mineworkers to MSDs was 4.57, which implies that the mineworkers were approximately 5 times more at risk of developing MSDs compared to the recruited unexposed cohorts. Meanwhile, wrist pain (43.58%) was the highest MSD complaints which lead miners to be absent from work, followed by knee and back with 35.42% and 21% respectively. Physical job risks, such as III working underground and squatting or kneeling at work were all significantly associated with MSDs recurrence in all six body parts (HR: 1.12-1.92, 95%CI). Similarly, time pressure to complete task, low decision latitude, poor job satisfaction, somatisation and mental disorder, job insecurity, poor incentive system (HR: 1.01-1.75, 95%CI) were perceived by stakeholders’ and participants alike in the study to be significantly associated with MSDs incidence. Quarrymen are exposed to high MSD risks associated with elevated psychosocial stress from their difficult work situations. The South Eastern Nigerian mine stakeholders believed that the high incidence of MSDs may have a substantial impact on health and productivity in the near future. Necessitating a clear need for the promotion of stakeholder’s engagement concerning safe work policy implementation initiatives in the sector.
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The influence of citrus orchard age on the ecology of entomopathogenic fungi and nematodes

- Albertyn ,Sonnica, Moore, Sean D, Marsberg, Tamryn, Coombes, Candice A, Hill, Martin P

  • Authors: Albertyn ,Sonnica , Moore, Sean D , Marsberg, Tamryn , Coombes, Candice A , Hill, Martin P
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/417545 , vital:71462 , xlink:href="https://hdl.handle.net/10520/ejc-cristal-v10-n1-a7"
  • Description: A three-year survey of the ecology of entomopathogenic nematodes (EPN) and entomopathogenic fungi (EPF) was undertaken on soils from citrus orchards of different ages to determine the influence of orchard age on the ecology of entomopathogenic fungi and nematodes. The influence of mulch and irrigation method on the occurrence of EPN and EPF was also determined. Most of the isolates recovered (n = 810) were Beauveria sp. (87.88% of all isolates), followed by Metarhizium sp. (11.87% of all isolates). Only 0.24% of soil samples collected during this study tested positive for EPN. All EPN isolates recovered were Heterorhabditis bacteriophora. No significant differences in EPF occurrence were recorded between orchards under drip and micro-sprinkler irrigation. EPF occurrence was significantly lower (P = 0.016) in orchards covered by mulch (31.85% ± 2.07% occurrence) than in orchards with no covering (38.57% ± 1.57% occurrence). EPF occurrence of 40.33 ± 2.13% was highest in non-bearing orchards, followed by mature orchards (nine years or older) (36.76 ± 2.05% of samples) with the lowest EPF occurrence of 25.30 ± 2.02% reported in juvenile orchards (four to eight years old). Juvenile orchards sustain significantly less EPF than mature and non-bearing orchards because of the combined negative impact of less favourable environmental conditions (lower shade density) and fungicide applications.
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The Influence of Life Orientation Sexuality Education on Attitudes to Sex and Sexuality in South Africa: A Systematic Review

- Groth, Michelle

The influence of the integration of local knowledge during chemistry hands-on practical activities on grade 8/9 learners’ attitude towards science

- Ngqinambi, Akhona

  • Authors: Ngqinambi, Akhona
  • Date: 2020
  • Subjects: Science -- Study and teaching (Secondary) -- South Africa , Science teachers -- South Africa , High school students -- Attitudes , Communities of practice -- South Africa , Science clubs -- South Africa , Science projects -- South Africa , Constructivism (Education) -- South Africa , Educational counseling -- South Africa , Local knowledge
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/144724 , vital:38373
  • Description: With every passing year, there is a decrease in the number of learners pursuing science degrees after completion of grade 12. One of the main reasons for this is the negative attitude that high school learners have towards science learning and science as an entity. The Natural Sciences curriculum suggests the use of local knowledge to introduce the usefulness and the relatability of science to learners. This study is an intervention that seeks to ascertain the influence that local knowledge has on the attitudes of grade 8/9 learners when integrated into their chemistry hands-on practical activities. The study was informed by Vygotsky’s social constructivist theory and Wenger’s community of practice theory. Grade 8/9 learners from four high school science clubs did three local knowledge integrated experiments based on acids and bases. The learners completed pre- and post- surveys and were interviewed about their experiences. Volunteers at the science clubs were also interviewed. Excel was used to deductively analyse quantitative data. On the other hand, an inductive-deductive thematic approach was used to analyse the qualitative data. The findings of the study showed a divergence of qualitative and quantitative methods. The quantitative data showed that there was a slight decrease (but not statistically significant) in the attitude of the learners after engaging in chemistry hands-on practical activities into which local knowledge had been integrated. On the other hand, the qualitative data showed that there was a positive shift in the learners’ attitudes after they had been engaged in the chemistry hands-on practical activities. Additionally, the findings of the study revealed that the integration of local knowledge promotes conceptual understanding and improves the performance of the learners. This study thus recommends that local knowledge should be integrated into the grade 8 and 9 learners’ curriculum to enrich and promote contextualized science for learners. Additionally, the integration of local knowledge would promote conceptual understanding and spark interest and motivation in learners to pursue science-related careers.
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The Integration of Personally-owned Information and Communication Technologies (PICTs) for Teaching and Learning in Resource-Constrained Higher Education Environments – The Case of a Nigerian University

- Lewis, Oláñrewájú Olúrotimi

  • Authors: Lewis, Oláñrewájú Olúrotimi
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/163582 , vital:41050 , doi:10.21504/10962/163582
  • Description: Thesis (PhD)--Rhodes University, Faculty of Commerce, Information Systems, 2020
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The international community’s implementation of the Responsibility to Protect (R2P) Principle: a Comparative Study of Sudan and Libya

- Nizeimana, John Bosco

  • Authors: Nizeimana, John Bosco
  • Date: 2020
  • Subjects: Responsibility to protect (International law) , Humanitarian intervention -- Libya , Libya -- Foreign relations -- 1969- , Libya -- Politics and government -- 1969- , Humanitarian intervention -- Sudan , Sudan -- Foreign relations , Sudan -- Politics and government -- 1985-
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/162631 , vital:40962
  • Description: In the history of international relations, the adoption of the R2P principle in 2005 was widely understood to be a break-through in the international community’s efforts to respond to massive human rights violations and atrocities. Despite this, the international community’s implementation of the R2P has been widely contested, including in relation to its application in Sudan and Libya. There is agreement in the literature that, in both cases, the implementation of the R2P failed to achieve its intended purpose of protecting civilian populations. This thesis addresses the question of why the R2P failed in Sudan and Libya. Most explanations concerning the failure of the R2P in Sudan and Libya tend to focus on the politics of big power countries. The study argues that the failure to implement the R2P is related to the interactions between regional organisations and the international community (global organisations like UN) in attempting to solve large-scale human rights violent conflict. The study is firmly embedded in scholarly debates about humanitarian intervention so as to demonstrate the fact that this study is part of efforts to advance knowledge of scholarly debates on humanitarian intervention in this contemporary world order. The study combines a case study approach and qualitative research approach to achieve a nuanced understanding of the reason why the R2P failed in Sudan and Libya. The study relied on the use of documentary reviews and in-depth interviews of experts to collect data which was analysed using critical discourse analysis. The thesis demonstrated that the implementation of the R2P was characterised by a breakdown of the relationship between regional actors like the AU and global institutions like the UN. This breakdown contributed to the failure of the R2P in Sudan and Libya. The lack of financial and operational capacity for rapid deployment, the internal divisions with the AU, and the lack of political will within the AU members states were also cited as obstacles to the realisation of the R2P efforts in Sudan. To establish in-depth knowledge the study revealed other factors related to the politics of big power countries and how they played a part in the failure of the R2P in Sudan and Libya. Among these factors include implementation inconsistencies, the ICC factor, the absence of UNSC consensus in the response over Darfur and Libya, and the veto power factor and its implications in the efforts of the international community in both cases. This study also showed that the implementation of the R2P may not work effectively if left only to international actors to implement. Regional and sub-regional actors are important stakeholders of the R2P, and their interactions with the international community in actualising the implmementation of the R2P on the ground are essential. The manner in which the R2P was applied in Sudan and Libya is an indication its implementation requires improved interaction between regional actors and the international community at all level of collaboration including at global, regional and sub-regional level. This can build a strong foundation to drive the effective implementation of the R2P in future interventions. The findings of this thesis will significantly improve the available literature on the reason why the R2P failed in Sudan and Libya, particularly by paying much attention to the role of regional and sub-regional actors.
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The invasive grass genus Nassella in South Africa: A synthesis

- Mapaura Anthony, Canavan, Kim N, Richardson, David M, Clark, Vincent R, Steenhuisen, Sandy-Lynn

  • Authors: Mapaura Anthony , Canavan, Kim N , Richardson, David M , Clark, Vincent R , Steenhuisen, Sandy-Lynn
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/424842 , vital:72188 , xlink:href="https://doi.org/10.1016/j.sajb.2020.08.031"
  • Description: Three species of Nassella have naturalized in South Africa. Nassella trichotoma and N. tenuissima are declared weeds under category 1b of the National Environmental Management: Biodiversity Act (NEM:BA) and occur mainly in the montane grasslands of the Western and Eastern Cape provinces. Nassella neesiana is not listed in NEM:BA but is naturalized in the Eastern Cape, Western Cape and Free State provinces. Research conducted in the 1970s and 1980s led to vigorous government-funded awareness and control campaigns which ended in 2000. No research on Nassella distribution or control has been undertaken since then. Despite this hiatus, Nassella remains a dangerous genus in southern Africa, given the serious impacts of these species in similar social-ecological systems in Australia and New Zealand. This paper presents a synthesis of available information about Nassella invasions in South Africa and identifies research gaps. It specifically addresses these questions: What identification issues exist? What is the current spatial distribution of Nassella? What is the autecology of the genus? What are the social-ecological impacts of Nassella? What control measures are currently applied and what are their strengths and limitations? What do we know about Nassella distribution and its response to climate change? This paper highlights many knowledge gaps about Nassella, such as the species’ current distribution range, field identification and detection difficulties, and the uncoordinated control efforts that require urgent research to inform an effective management response.
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The Islamic Bloc at the United Nations Human Rights Council

- Rist, Duncan Graham

  • Authors: Rist, Duncan Graham
  • Date: 2020
  • Subjects: United Nations Human Rights Council , Organisation of Islamic Cooperation , International relations , International relations -- Moral and ethical aspects , Political leadership -- Moral and ethical aspects , Power (Social sciences) -- United States , Human rights -- International cooperation , Liberalism -- International cooperation
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/142759 , vital:38114
  • Description: Uncertainty as to the future of the liberal international order and the position of the United States within an international system in which it is not the hegemon remains a topic of debate amongst scholars of International Relations (Acharya: 2017; Duncombe and Dunne: 2018; Ikenberry: 2009, 2011, 2014; Nye: 2012 and Monteiro: 2011/2012). Fukuyama’s (1989: 4) “end of history” has not happened and a resurgence of populist leaders within established liberal democratic countries has contributed to a rapid decline of moral and ethical leadership and has further compromised the future of the liberal international order (Duncombe and Dunne, 2018: 27). As the relative power of the United States declines and the future of the liberal international order becomes increasingly uncertain, support for its future must be sought from outside the West (Duncombe and Dunne, 2018: 25 and Ikenberry: 2009). This thesis seeks to locate where potential non-Western support for the future liberal international order may be found. It does so through an analysis of how Islamic states who are part of the Organisation of Islamic Cooperation vote on the United Nations Human Rights Council (UNHRC). The OIC has a significant presence at the UNHRC and can influence the direction of the liberal international human rights regime. The evidence examined in this research project suggests that the future liberal international order and human rights regime can indeed expect some form of cooperation from the OIC. However, the OIC, and by extension Islamic states, would likely offer more support at least for human rights, if a more common understanding were to be found.
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The Legacy Effects of Colonial and Apartheid Imprints on Urban Greening in South Africa: Spaces, Species, and Suitability

- Shackleton, Charlie M, Gwedla, Nanamhla

  • Authors: Shackleton, Charlie M , Gwedla, Nanamhla
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/176296 , vital:42682 , https://doi.org/10.3389/fevo.2020.579813
  • Description: Colonialism is a significant legacy across most aspects of urban form, the nature and distribution of public green spaces, and tree species composition in many cities of the Global South. However, the legacy effects of colonialism on urban green infrastructure and the uses thereof have only recently come under scrutiny. Here we collate information from South Africa on urban greening and interpret it through a colonial and apartheid legacy lens in relation to the distribution and types of urban nature found and their resonance with contemporary needs as an African country.
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The lived experiences of women with human immunodeficiency virus (HIV) in Malawi: an interpretative phenomenological analysis (IPA)

- Nkhalamba, Mathero Michelle

  • Authors: Nkhalamba, Mathero Michelle
  • Date: 2020
  • Subjects: HIV-positive women -- Malawi , HIV infections -- Sex factors -- Malawi , HIV infections -- Social aspects -- Malawi , HIV-positive women -- Malawi -- Social conditions , HIV-positive women -- Malawi -- Economic conditions , Poverty -- Malawi , Antiretroviral agents -- Malawi , Phenomenological psychology
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/145291 , vital:38425
  • Description: Research on African women and HIV, particularly research that investigates their experiences of living with the virus, has been relatively peripheral. As a response to the apparent knowledge and research gaps, this project is a qualitative study involving women living with human immunodeficiency virus (WLHIV) and attending an anti-retroviral treatment (ART) clinic at Zomba Central Hospital in Southern Malawi. The study utilised an interpretative phenomenological analysis (IPA) approach, which informed all aspects of the data-collection and data-analysis processes. Using purposive sampling, 12 women were recruited and interviewed on three occasions over a period of six months. The interviews were conducted in Chichewa and audio recorded and later transcribed into English. Fourteen superordinate themes emerged from the analysis representing the women’s prominent life experiences, how they received their diagnosis, and how they contained the trauma of their diagnosis. The analysis also developed themes regarding how they coped with the challenges of living with the human immunodeficiency virus (HIV) and made sense of their experiences. The results showed that the women struggled with multiple challenges experienced through their various identities as WLHIV. The findings also pointed to interlocking disadvantages that put the women at risk of infection, and which were present from childhood. This has implications for more structural and multidisciplinary interventions for WLHIV.
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The long road to Rhodes University: narratives of African first-generation students whose mothers are/were domestic workers

- Mapele, Nomonde

  • Authors: Mapele, Nomonde
  • Date: 2020
  • Subjects: Household employees -- Children -- South Africa , Women household employees , Rhodes University -- Students , Black people -- Education (Higher) -- South Africa , Students, Black -- South Africa -- Personal narratives , First-generation college students
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/150530 , vital:38982
  • Description: First-generation African students contend with psychosocial, structural, educational background and financial struggles to gain access to university. The first-generation students exercised their available resources and power, agency and acquired skills to negotiate their journey and entrance to university. They had to figure out for themselves how to navigate a daunting and complex path to university without relying on the knowledge and informative engagement with previous older familial generations who had the experience of attending university. They are a testimony of a generation of young people who have the resilience and grit to compensate for the structural deficits they have and experienced through their disadvantaged educational systems and their financially disadvantaged backgrounds. Although one would expect that teachers would automatically be the first encounter a high school student has of acquiring information on how to gain access to university, many of the previously disadvantaged school teachers are simply too inundated with work to be able to facilitate this process. First-generation students found themselves mostly having to look beyond the parameters of the classroom to acquire these resources. Following a qualitative approach of narrative enquiry, five African students with life experience of being first-generation Rhodes University students whose mothers were or are domestic workers, narrated their personal stories. A first-generation student’s agency, negotiation and navigation through obstacles, struggles and setbacks in the backdrop of having mothers who were/are domestic workers who socialised their children in a specific ideology to value and pursue education are the foundations for this narrative enquiry. This research provides a framework for investigating the concept of adequate and appropriate university preparedness to address the inadequate resources that previously disadvantaged schools have in terms of preparing their students to compete (in often times with more advantaged students) to gain access to university. These first-generation students did not come from educational environments where career counselling or aptitude tests are done to better equip them for entrance into university and appropriate subject and degree choice. Several common traits emerged that give perspective to the narrative of the journey that first-generation students’ had to endure and overcome to gain access to university.
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The management of lions (Panthera Leo) in small, fenced wildlife reserves

- McEvoy, Orla

  • Authors: McEvoy, Orla
  • Date: 2020
  • Subjects: Lion -- Behavior -- South Africa , Spatial behavior in animals -- South Africa , Animal populations -- South Africa , Game reserves -- South Africa -- Management
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/143471 , vital:38249
  • Description: Reintroduced lion (Panthera leo) populations pose several ecological and management challenges in small (< 1,000 km2), fenced wildlife reserves. Changes in the natural socialecological conditions of reintroduced lion populations may lead to rapid population growth and a breakdown of natural predator-prey relationships. Reduced competition with other lions also likely reduces the potential for reintroduced lions to naturally form groups. My study used a combination of questionnaire surveys with tourists, existing lion demographic data from 16 wildlife reserves across South Africa and a controlled lion social experiment to address these ecological and management issues. Tourism was the primary reason for lion reintroductions. Tourists scored lions highly in terms of preference for viewing on safari, in particular, lions in larger, natural groups and adult males. Viewing lions also enhanced a tourists’ overall safari experience. The breakdown of natural social behaviour may likely therefore reduce tourist satisfaction related to lions. The number of resident prides and male coalitions in a reserve affected lion vital rates. Lion population growth rate was highest in reserves that contained a single resident pride, and the presence of unknown adult males significantly reduced cub survival and lioness birth intervals. The ratio of male cubs born also increased in reserves with a higher density of unknown adult males. Fertility control measures (deslorelin implants and unilateral hysterectomy) were effective at limiting lion population growth. Deslorelin treatment increased the age of first reproduction or the birth interval and decreased the subsequent litter size of treated lionesses to closer reflect natural vital rates in larger (> 10, 000 km2) systems. However, there was variability in infertility response between lionesses including adverse reactions in a small proportion of treated individuals. The number of resident prides and male coalitions in a reserve affected lion social behaviour. Lionesses formed larger groups in reserves with a higher density of unknown adult female neighbours, likely driven by territory defence. Lion prides with resident cubs were generally more fragmented, likely in response to reduced competition from unknown adult males. However, in areas with a high density of unknown adult female neighbours, prides with cubs formed larger groups likely in response to heightened territory defence. Therefore, with smaller foraging group sizes, predation rate was increased in reserves with reduced competition from unknown lions. My study supports a metapopulation approach for the management of lions in small, fenced reserves, and the standardisation of lion management procedures and database management. Endorsed by the Biodiversity Management Plan for lions in South Africa, this will enhance the long-term conservation potential of isolated populations.
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The meanings selected Rhodes University student-fans of hip-hop make of the gendered scenarios portrayed in designated South African commercial hip-hop music videos

- Mtengwa, Tamuka Phumelela Msawenkosi Misheck

  • Authors: Mtengwa, Tamuka Phumelela Msawenkosi Misheck
  • Date: 2020
  • Subjects: Hip-hop -- South Africa , Misogyny -- South Africa -- Makhanda , Rap (Music) -- South Africa , Rap (Music) -- Social aspects -- South Africa , Hip-hop -- Influence , Violence in music , Women -- Violence against -- South Africa , Rape culture -- South Africa , Rap music fans-- South Africa -- Makhanda , Misogyny in music , #RapeCultureMustFall , #RUReferenceList
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/148305 , vital:38728
  • Description: Hip-hop is frequently linked to misogyny and other forms of violence. This link, in many instances, is often presented outside of a critical understanding of complex underlying societal and gender dynamics. South Africa’s high rates of violence against women make it necessary to understand how hip-hop videos interact with society, as hip-hop, in its commercial form, has become a growing music genre in South Africa. Rhodes University, which has a notable student following of hip-hop, has experienced concerning levels of gender-based tensions as evidenced by the rise of the “fallist” movement’s #RapeCultureMustFall, #RUReferenceList and the suicide of Khensani Maseko, at the instigation of an alleged incident of rape, perpetrated by her boyfriend and fellow student. It is therefore of interest to investigate how a select group of Rhodes University student-fans of hip-hop make meaning out of selected South African commercial hip-hop music videos. The hip-hop music videos chosen for the study, hence Pitbull Terrier (Die Antwoord), Pearl Thusi (Emtee), Dlala ka yona (L’Tido), All eyes on me (AKA featuring Burna Boy, Da L.E.S and JR) and Ragga Ragga (Gemini Major featuring Casper Nyovest, Riky Rick and Nadia Nakai), were selected on the strength of their popularity and uniquely gendered scenarios. This study draws on qualitative research methods, thus qualitative thematic content analysis, focus group and in-depth interviews. The study establishes that despite gender being a contentious issue at Rhodes University, students make meaning out of the gendered portrayals based on their own experiences, socialisation, cultural values and level of submission to the discourse of hip-hop. This study seeks to understand how selected student-fans of hip-hop read the gendered portrayals of the music videos, based on their own experiences, socialisation, cultural values, and level of submission to the discourse of hip-hop.
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The modulation of the photophysical and photodynamic therapy activities of a phthalocyanine by detonation nanodiamonds: Comparison with graphene quantum dots and carbon nanodots

- Matshitse, Refilwe, Managa, Muthumuni, Nyokong, Tebello

  • Authors: Matshitse, Refilwe , Managa, Muthumuni , Nyokong, Tebello
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/186690 , vital:44525 , xlink:href="https://doi.org/10.1016/j.diamond.2019.107617"
  • Description: A positively charged phthalocyanine (2,9,16,23-tetrakis[4-(N-methylpyridyloxy)]-phthalocyanine (ZnTPPcQ)) was non-covalently linked to carbon based nanoparticles: detonation nanodiamonds (DNDs), carbon dots (CDs) and graphene quantum dots (GQDs) to form nanosembles of DNDs-ZnTPPcQ, GQDs-ZnTPPcQ and CDs-ZnTPPcQ, respectively. Irrespective of its small size and the least number of Pcs (41.67 μg loading per milligram of DNDs), DNDs-ZnTPPcQ gave the highest singlet oxygen quantum yield (0.62) in dimethyl sulfoxide compared to the rest of the conjugates. This resulted in superior PDT activity against MCF7 breast cancer lines, with the lowest cell viability of 28% compared to ZnTPPcQ-CDs and ZnTPPcQ-GQDs at 30.1 ± 0.02% and 31.4 ± 0.23%, respectively.
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The Northern Cross fast radio burst project–I: overview and pilot observations at 408 MHz

- Locatelli, Nicola T, Bernardi, Gianni, Bianchi, Germano, Chiello, Riccardo C, Magro, Alessio, Naldi, Giovanni, Pilia, Maura, Pupillo, Giuseppe, Ridolfi, Alessandro, Setti, Giancarlo, Vazza, Franco

The novobiocin-induced turnover of fibronectin via low density lipoprotein receptor-related protein 1 alters matrix morphology with physiological consequences on cell growth and migration

- Boёl, Natasha Marie-Eraine

  • Authors: Boёl, Natasha Marie-Eraine
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/114778 , vital:34034 , 10.21504/10962/114778
  • Description: Fibronectin (FN), an extracellular matrix protein, is secreted as a soluble dimer which is assembled into an insoluble extracellular matrix. The dynamics of FN matrix assembly and degradation play a large role in cell migration and invasion thereby contributing to the metastatic potential of cancer cells. Previous studies have shown the direct binding of Heat Shock Protein 90 kDa (Hsp90) and FN in vitro, and that inhibition of Hsp90 with novobiocin (NOV) caused internalisation of the FN matrix. Low density lipoprotein receptor-related protein 1 (LRP1) is a ubiquitous receptor known to bind both Hsp90 and FN. Using an LRP1 expressing Hs578T breast cancer cell line and an isogenic mouse embryonic fibroblast (MEF) model system of differential LRP1 expression we demonstrate that LRP1 is involved in turnover of FN in response to C-terminal Hsp90 inhibition. The first objective of this study was to identify the mechanism of NOV-induced LRP1-mediated FN turnover. Our data show that NOV-mediated FN turnover via LRP1 did not require the activity of matrix metalloproteinases (MMPs), which play an important role in processing and degradation of the extracellular matrix and FN. In addition, the levels of the main FN receptor responsible for its extracellular assembly, β1-integrin, did not change in response to NOV. LRP1 is known to undergo regulated intramembrane proteolysis (RIP) which generates smaller fragments that may translocate to the nucleus and modulate gene transcription. Using inhibitors of LRP1 cleavage and nuclear fractionation we determined that LRP1 processing was not required for the NOV-induced FN response suggesting that a mechanism unrelated to LRP1 RIP is involved. A possible mechanism may be in altered Hsp90-LRP1 cell signalling as we observed disruption of the FN-Hsp90-LRP1 complex at the cell surface in NOV treated cells. How this affects downstream eHsp90-LRP1 signalling is still to be determined but may be related to a significant increase in phospho-AKT and loss of phospho-ERK upon NOV-treatment; two key signalling proteins involved in FN matrix regulation and which are downstream of LRP1 signalling. The second objective of this study was to determine the physiological consequences associated with FN turnover in response to NOV treatment. Using migration assays we demonstrated that levels of insoluble matrix-associated FN and FN concentration are not solely responsible for migratory capacity of cells on decellularized extracellular matrices, but rather that structural composition and integrity of the matrix plays a bigger role. Using confocal and scanning electron microscopy, we identified NOV treated matrices to be flatter, less mature and contain thicker, rope-like FN fibrils to which cells adhered better but were generally less proliferative. Comparatively, cells adhered less to the more mature and 3-dimensional untreated matrices but exhibited increased spreading and cell growth, which may in part be due to the thinner fibrils and web-like matrix. In summary, this study substantiates the role of LRP1 in NOV-mediated FN turnover, and provides new insights into the possible mechanisms of the Hsp90-LRP1 mediated loss of FN matrix. This is the first study to demonstrate some of the functional consequences related to FN turnover by NOV at the ECM level. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2020
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The past meets the present: exploring the biogeography of extant plecoptera of South Africa with reference to ancient middle permian fossil forms from the Onder Karoo locality near Sutherland

- Kirkaldy, Benjamin Puleng

  • Authors: Kirkaldy, Benjamin Puleng
  • Date: 2020
  • Subjects: Stoneflies, Fossil -- South Africa -- Northern Cape , Palaeopteron -- South Africa -- Northern Cape , Stoneflies -- Evolution , Insects, Fossil -- South Africa -- Northern Cape , Paleoentomology , Paleoentomology -- South Africa -- Northern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/165755 , vital:41278
  • Description: The Onder Karoo fossil locality near Sutherland, Northern Cape, recently yielded an unprecedented diversity of middle Permian insects, which were preserved in deposits of an aquatic lake margin system, in the Lowermost Abrahamskraal Formation. A large number of Plecoptera (stonefly) specimens were found, and this study represents an in-depth analysis of these species in the context of plecopteran evolution. A significant contribution to current knowledge of the Plecoptera from the middle Permian to the present has been made, utilizing a combination of fossil and phylogenetic evidence to better understand the origins, evolution, diversity and biogeography of the stoneflies. Three new plecopteran species have been described from the Onder Karoo locality, which is recognized here as the first Lagerstätte of its kind in Gondwana. Possible ecological links and relationships with the plecopterans described here have been suggested, using extant Plecoptera as analogues. An in-depth, fossilcalibrated, dated phylogeny of the Plecoptera was completed, using representatives from all three dominant lineages, the Antarctoperlaria, Systellognatha and the Euholognatha. This provides strong support for the monophyly of the Notonemouridae and the Antarctoperlaria, however the monophyly of Systellognatha and Euholognatha was not supported. The Notonemouridae were found to represent an earlier divergence than previously believed, forming a sister group to the remaining Plecoptera. Through a combination of fossil and molecular evidence, strong support was found for the current distribution of the Plecoptera worldwide being attributable to vicariance caused by the rifting of Pangea, and subsequently Gondwana and Laurasia, and long range dispersal. The focussed effort to include Southern Hemisphere stoneflies throughout this study has been a valuable step in reducing the Northern Hemisphere bias which currently dominates plecopteran research and has assisted in opening the way for future research into this important group on a global scale.
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The photodynamic antimicrobial chemotherapy of Stapphylococcus aureus using an asymmetrical zinc phthalocyanine conjugated to silver and iron oxide based nanoparticles

- Mapukata, Sivuyisiwe, Nwahara, Nnamdi, Nyokong, Tebello

  • Authors: Mapukata, Sivuyisiwe , Nwahara, Nnamdi , Nyokong, Tebello
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/186078 , vital:44461 , xlink:href="https://doi.org/10.1016/j.jphotochem.2020.112813"
  • Description: The synthesis and characterisation of asymmetrical zinc(II) 2(3)-mono-isophthalic acid-9(10),16(17),23 (24)-tri (tert-butylphenoxy) phthalocyanine (complex 4) are reported. The phthalocyanine is conjugated to cysteamine capped silver nanoparticles (Cys-Ag NPs), amine functionalised iron oxide magnetic nanoparticles (NH2-Fe3O4 NPs) and a core-shell composite of the two (Cys-Fe3O4@Ag) via amide bonds. The photo-physico-chemical properties of complex 4 and its respective nanoconjugates (4-Ag, 4-Fe3O4 NPs and 4-Fe3O4@Ag NPs) are also reported. The nanoconjugates showed improved triplet and singlet oxygen quantum yields compared to complex 4. The antibacterial activity of complex 4 and its nanoconjugates were also evaluated on S. aureus wherein their activity was found to be mainly visible light driven with the best catalyst being 4-Fe3O4@Ag. The work therefore demonstrates the feasibility of phthalocyanine-nanoparticle based compounds as potential agents in real life antibacterial treatment
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