4. Electronic Theses and Dissertations (ETDs) - Faculties submissions
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Item Bypassing the union: An Employer's Right to Negotiate Directly with Striking Employees(University of the Witwatersrand, Johannesburg, 2016-08) Nkosi, Thulani Gift; Mahomed, ShahedaSouth African labour law influenced by the Constitution and notions of equity and fairness has undergone a total change and will, without doubt, continue to change to meet the ever changing nature of employment it seeks to regulate. It is after all in the nature of all laws to change with the society they seek to regulate and our labour law is no exception. Recently, focus has shifted to the institution of collective bargaining and the questions posed are whether our labour laws as they currently stand are capable of adequately regulating the process of collective bargaining in such a way that the main objective of collective bargaining which is to bring about industrial peace is promoted and maintained at all times. These questions are posed on the back of the unprecedented spates of prolonged violent strikes that have resulted in the destruction of property and loss of life as well as unimaginable financial losses not only for the employers affected but also for the economy as a whole. These unprecedented prolonged violent strikes have caused employers to engage in bargaining conduct that could erode the participation of trade unions from the collective bargaining process which bargaining conduct takes the form of employers bypassing trade unions and negotiating with striking employees directly. But do employers have a right to bypass trade unions in this way? This paper investigates this question against the background of the case of Amcu v Lonmin where the Labour Court on application by a trade union had to decide whether to grant an urgent interdict restraining employers from negotiating directly with striking employees. The employers considering themselves to be acting within their rights opposed the application. The Labour Court unfortunately dismissed the application on technical grounds relating to the lack of urgency without considering or deciding this question. This paper accordingly picks up the debate; considers the historical evolution of collective bargaining in our labour law including the voluntarist argument that is said to be embodied by the Labour Relations Act (LRA), and concludes that when all things considered employers in fact do not have a right to bypass trade unions. If employers had this right certain provisions of the LRA that guarantee trade union participation would be rendered nugatory and the whole collective bargaining process would become unworkable. The LRA envisions that once parties have voluntarily embarked on collective bargaining they bargain in good faith and do not bypass each other.Item The perceptions of social workers on the implementation of the Occupation Specific Dispensation policy (OSD) within the Department of Social Development in the Johannesburg Region(University of the Witwatersrand, Johannesburg, 2020) Mathebula, Sipho Sol; Masinga, PoppyThe Occupation Specific Dispensation (0SD) policy was introduced in the public service for social workers in 2009 as a strategy to recruit and retain social workers with the introduction of new salary scales, career pathing, pay and grade progression and recognition of appropriate experience. The perceptions of social workers on the implementation of the OSD policy have not been established and this lack of knowledge leaves a gap in understanding the perceived impact this policy has had on social workers. The aim of the study was to explore the perceptions of social workers on the implementation of the Occupation Specific Dispensation policy within the Department of Social Development in the Johannesburg Region. Since implementation of the policy, there has been research studies conducted on the outcomes of the OSD policy within the public health sector yet no studies have been conduct that focus on the challenges encountered by social workers in the implementation of the policy. The study utilised the qualitative research approach which was exploratory and descriptive in nature. The collective case study design was adopted. A sample of ten social workers and three key informants were selected using purposive sampling. Data was collected using semi-structured interviews and analysed using thematic content analysis. The key finding was that the OSD policy was not effective in recruitment since it is rigid and inflexible. Another concern raised was the long period it took to move from one occupational level to the next resulting in a demotivated and demoralised workforce. The study also found that there was management bias in the implementation of the performance management and development system. The study contributes to our understanding of the perceptions about the unintended consequences of the OSD policy and how these are perceived to have impacted negatively on the recruitment and retention of social workers.Item Design and development of a bioactive-loaded polymer-engineered neural device for potential application in reducing neurological deficits after spinal cord injuries and neuro-regeneration(University of the Witwatersrand, Johannesburg, 2017) Kumar, Pradeep; Choonara, Yahya Essop; Modi, Girish; Naidoo, Dinesh; Pillay, VinessTraumatic Spinal Cord Injuries (SCI), due to their devastating nature, present several interventional challenges (extensive inflammation, axonal tethering, scar formation, neuronal degeneration and functional loss) that need to be addressed before even a slight neuronal recovery can be achieved. Recent post-TSCI investigational approaches include support strategies capable of providing scaffold architecture to allow axonal growth and conformal repair. This research provided detailed insight towards the development and fabrication of six specialized Polymer-Engineered Neural Devices (PENDs): 1) poly(lactic-co-glycolic acid)-gliadin (PLGA-GLDN) nanofibrous mats, 2) polyacrylamidated chitosan (PAAm-g-HT) scaffold, 3) functionalized chitosan methoxypolyethylene glycol (CHT-mPEG) cryosponges, 4) polyacrylonitrile-elastin-collagen (PANi-EC) neurosponge, 5) methylcellulose-alginate-polyethylene glycol (MAP) thermogel, and 6) chitosan-luronic F127-β glycerophosphate (CHT-PF127-βGP) composite thermogel for potential restriction, repair, regeneration, restoration and reorganization post-SCI. The latest trends in biomaterials-based SCI intervention were reviewed, discussed and analyzed in detail throughout the thesis. The research also involved an in silico analytico mathematical interpretation of multi(biomed)material assemblies wherein quantification of energy surfaces and molecular attributes via atomistic, dynamic, and docking simulations was carried out. The in silico experimentation additionally confirmed the potential of curcumin as a bioactive of choice for SCI intervention. Curcumin and dexamethasone were incorporated into the compact scaffolds and the bioactive release was determined over a period extending up to 60 days. The PLGA-GLDN nanofibrous mats demonstrated the formation of a compatible blend among the component polymers at equal weight ratios (PG55) as confirmed by quantitative physicochemical characterizations. Image processing analysis (DiameterJ plug-in of ImageJ) was performed on the SEM images of nanofibers to quantify the size, porosity, and orientation of the samples. Nanofibers within the size range of 10nm and 250nm were obtained in case of compatible blend and the nano stack was used for in vivo implantation post-SCI. Polyacrylamidated chitosan (PAAm-g-CHT) was synthesized via a unique persulfate-mediated polymer slicing and complexation as determined by static lattice atomistic simulations. The graft copolymer so obtained was fabricated into an anisotropic neurodurable scaffold. The CHT/mPEG cryosponges showed unique morphological features such as fringe thread-like structures (CHT alone); hemispherical, pebble-like structures (CHT-mPEG); curved quartz crystal-like or crystal-flower-like structures (CHT-mPEG-CHO); and grouped, congealed, steep-sided canyon-like structures (CHT-mPEG COOH). A novel image processing protocol involving DiameterJ and ND plugins of ImageJ software was employed for analyses of the SEM micrographs in terms of % porosity, pore wall thickness and % xiiehaviorxii of the porous scaffolds. The PANi-EC interpenetrating polymer network neurosponges were synthesized employing free radical polymerization under acidic conditions wherein first-in-the-world spinomimetic scaffolds were obtained. The unique feature of the PANi-EC neurosponge was the formation of a fibrous neurotunnel architecture mimicking the native spinal cord. The physicochemical characterization revealed that the secondary structure of the peptide molecules (elastin and collagen) rearranged in the presence of PANi to their native extracellular matrix (ECM) form confirming the self-assembling nature of the polymer-peptide architecture. Furthermore, the PANi-EC neurosponge provided a perfect balance of matrix resilience and matrix hardness similar to the native collagen-elastin complex in vivo. Two very interesting tri-component thermogels were reported here viz. a simple blend thermogel comprising methylcellulose, sodium alginate and poly(ethylene glycol) and a complex thermogel incorporating chitosan, Pluronic F127 and β-glycerophosphate. Both the thermogels solidified at physiological temperature confirming their applicability in vivo. The outstanding feature of MAP thermogels was the formation of hydrogen bonded O-H…C=O which only formed in the tripolymeric blend while the bipolymeric blends showing no such interaction. We proposed that the MAP thermogel self-assembled into a repeating network structure represented by “PEG400-ALG-hydrophillicMChydrophobic}-{hydrophobicMC-hydrophilic}-ALG-PEG400” and the physical “compression” might have led to the formation of hydrogen bonded O-H…C=O among MC/alginate or PEG/alginate in the presence of PEG or MC, respectively. In case of the complex CHT/PF127/βGP thermogel, a unique triphasic gel-sol-gel transition xiiehavior was observed with the thermogel forming a gel-phase at lower temperatures (T<20°C), a sol-phase at intermediate temperatures (20°C35°C). The MTT proliferation studies indicated that all polymer engineered neural devices (PANi-alone matrix) were capable of efficiently supporting the growth of PC12 cells compared to the control over a period of 72 hours. The fundamental objective of this thesis was to test the applicability and capability of various biomaterial composites towards the repair and regeneration of neuronal tissue after traumatic spinal cord injury. Although drug-loaded scaffolds were also developed, only drug-free scaffolds (PLGA-Gliadin 5:5 electrospun nanofibers; PANi-Elastin-Collagen neurosponge; and Chitosan/Pluronic F127/β-glycerophosphate thermogel) were tested in vivo for the proof-of-concept. The 21-point scale BBB locomotor rating analysis demonstrated that PEND I (14), PEND II (19) and PEND III (18) provided significant motor recovery as compared to the lesion-control (5) group 28 days post-SCI and –implantation. The immunohistochemistry confirmed that reparative changes were accompanied by marked upregulation of iNOS, a notable influx of ED1-positive chronic inflammatory cells, the appearance of multinucleate cells characteristic of presumptive regenerative neuroblasts and near-complete loss of GFAP and NF-200 protein/structural integrity. Almost complete functional and neurostructural recovery was observed with post-SCI implantation of PEND II and III. In conclusion, the composite scaffolds tested in this research demonstrated immense potential in improving the neurological, neurochemical, and behavioral outcome after implantation post-SCI.Item Co-gasification of Coal and Solid Waste to Hydrogen Enriched-Syngas in a Fixed Bed Gasifier(University of the Witwatersrand, Johannesburg, 2020-10) Ozonoh, Maxwell; Daramola, Michael O.; Oboirien, Bilainu O.The economic growth of every nation around the globe is centred on energy. Energy can be harnessed from different sources using different conversion systems, but such systems should be sustainable. Liquid fuels such as petroleum and solid fuels (e.g. coal & biomass) are largely used for energy production. Energy recovery from these fuels is usually carried out using thermal chemical processes such as combustion, pyrolysis, and gasification systems. Out of the three technologies, gasification is considered the most attractive based on its efficiency and other qualities. In the gasification process, syngas is produced. It is necessary to produce syngas of high quality such as hydrogen-enriched syngas. Hydrogen-enriched syngas can be used in fuel cells, gas turbines and engines for electricity production. This type of gas burns with little gaseous emissions to the atmosphere, but its production is dependent on the type of fuel and process conditions, and energy conversion system employed. In South Africa, around 95 % of electric power production comes from coal, and the current reserve is projected to last not more than a century [8]. Secondly, the coal is fast depleting and generates a lot of gaseous emissions (e.g. CO2, NOX & SOX) that pose a huge threat to the environment. The emission of the aforementioned gases is a very serious issue in South Africa. Presently, some Carbon Capture and Storage (CCS) projects are on-going in the country, although the CCS is not the fuse of this study. The gasification of biomass waste and coal could assist in gaseous emission reduction. Similarly, large amounts of agricultural wastes (e.g. sugarcane bagasse, corn cob & pine saw dust) and other solid waste such as tyre are in abundance in SA. It is detailed in chapter 2. Majority of the wastes are disposed indiscriminately, hence resulting in environmental pollution. Importantly, the solitary gasification of biomass is very expensive considering the prices of biomass. Besides that, biomass produces large amount of tar hence, resulting in operational difficulties in the gasifier and end user facilities. In this study, co-gasification of coal and solid wastes is considered as a crucial alternative to addressing the aforementioned problems. Particularly, the feedstocks used for this study were coal, biomass (corn cob (CC), pine sawdust (PSD), sugarcane bagasse (SCB)) and waste tyre (WT) and were pre-treated by drying, milling, sieving, and torrefaction (coal was not torrefied). The fuel samples were blended with coal at different ratios as detailed in the thesis and used for the study. For the torrefaction process, the most viable torrefaction process conditions and feedstock were determined, while the torrefaction process model for the feedstocks were developed, using Response Surface Methodology (RSM) and Artificial Neural Network (ANN), respectively. The Performance efficiency of gasification systems was evaluated using experimental data obtained from a few gasifiers (e.g. entrained, fluidised, and fixed bed) operated at varied experimental conditions using blends of feedstocks (e.g. biomass, coal, waste tyre etc.). A backpropagation Levenberg Marquardt (L-M) and Bayesian Regularisation (BR) algorithms of ANN model with Multiple Input- Multiple Output (MIMO) and Multiple Input-Single Output (MISO) layer networks were considered. The results of the MIMO and MISO layer networks obtained from the L-M algorithm were better than that of BR algorithm which is in affirmation with some of the results found in the literature. For model result improvement, Input Variables Representation Technique-by-Visual Inspection Method (IVRT-VIM) and Output Variables Representation Technique-by-Visual Inspection Method (OVRT-VIM) were developed from the study. Estimation of the gaseous emissions and profits from biomass, tyre, and coal fired co-gasification CHP Plant using Artificial Neural Network (ANN) was carried out for 20-year investment period using South Africa (SA) and Nigeria as cases studies via Artificial Neural Network (ANN). Higher profits were obtained from South African feedstocks than that of Nigerian feedstocks due to cheaper price of SA coal WFO and WOFC, but the gaseous emissions (CO, NOX, & SO2) from the Nigerian fuels were lower than that of SA because of differences in compositions of the fuels. The potentials of biomass torrefaction in terms of profitability in a co-gasification CHP plant for a 20-year-investment period was carried out using blends of Coal + SCB, Coal + CC, and Coal + PSD with coal-to-biomass ratio of 50:50, 71:29, and 80:20, respectively. The two financial cases mentioned earlier were considered. Four investment terms including: (A) 1st–5th, (B) 5th– 10th, (C) 10th– 15th & (D) 15th– 20th and two operational cost models; with feedstock costing (WFC) and without feedstock costing (WOFC) were employed. An estimated profit of between USD5.9 million - USD6.5 million and USD7.8 - USD7.9 million was earned at the end of investment plan using WFC and WOFC, respectively. The Internal Rate of Return (IRR) was 5 ± 1 %/yr. and 7 ± 4 %/yr. based on South African electricity price of 0.14 $/c kWh, respectively. The parametric effect of process variables during torrefaction of coal/biomass/waste tyre blends using ANN and RSM models were studied. The variables considered were Higher Heating Value (HHV), Enhancement Factor (EF), and Sold Yield (SY). The most effective operating process conditions (in terms of blending ratio, temperature and torrefaction time: input variables) is of the order: 50:50 at 300 OC and 45 min > 50:50 at 250 OC and 30 min >50:50 at 200 OC and 45 min. Similarly, the most viable fuel follows the order of Coal + Torrefied PSD > Coal + Torrefied SCB > Coal + Torrefied CC and > Coal + Torrefied WT. Coal + Torrefied PSD has HHV of 28.27 % and an EF of 1.41. This corresponded to around 10 % increase in the HHV of the torrefied fuel when compared to the raw fuel and about 25.23% higher than the EF of Coal + Torrefied WT of 1.03. Based on the result of the EF of Coal +Torrefied waste tyre, upgrading of the fuel quality via torrefaction is not recommended. Furthermore, a comprehensive study on tar treatment techniques was carried out using tars produced from biomass and blends of biomass and coal employing biochar based and Ni-biochar based catalysts. Box Behnken Design of Experiment (DoE) method was used. A full quadratic regression model was used to develop a mathematical model for tar treatment based on the feedstocks studied. The Pine Sawdust-Biochar Catalyst (PSD-BC) and Nickel Pine Sawdust-Biochar Catalyst (Ni-PSD-BC) were the most effective in terms of tar treatment and with an average percentage amount of tar conversion of 89.76 and 96.73%, respectively. Ni-PSD-BC was more efficient for tar cracking than PSD-BC, but PSD-BC (waste base) may be more attractive if sustainability and cost effectiveness of precursors are considered. Co-gasification of coal and pine sawdust (PSD) to hydrogen enriched syngas in a fixed bed gasifier was carried out with catalyst (WCAT) at 900 OC and without catalyst (WOCAT), at 700, 800, and 900 OC, respectively. Coal-to-PSD ratio of 1:1 was used, while Nickel-pine sawdust-biochar (Ni-PSD-BC) and pine sawdust-biochar (PSD-BC) were employed as catalysts. The gases produced at 700, 800 & 900 OC using WOCAT cannot be used in fuel cells and gas turbines due to poor quality, while others produced at 900 OC WCAT, can be used in internal combustion engines and gas turbines, but unfortunately, have lower quality to be employed in fuel cells for electricity production. However, the study provides a method of beneficiation of the high ash content South African coal for energy production. The outcome of this study is also instrumental to energy security, efficiency and sustainability as well as waste management in South Africa, Nigeria and other parts of the globe. An assessment of the economic, energy and environmental viability of a 5 MW co- gasification power plant was carried out, using blends of coal and biomass, and two financial cases were considered namely: with feedstock costing (WFC) and without feedstock costing (WOFC). Feedstock profitability in the plant for energy production was evaluated. Equipment consisting was not considered. The power plant used 20,473,451.41 kg, 20,986,049.96 kg, 18,251,806.49 kg, and 15,276,277.85 kg of Coal + SCB, Coal + CC, Coal + PSD, and Coal + WT to produce the 5 MW and 5.56 MW electric and thermal power, annually. Coal + Torrefied PSD was the most profitable of the fuels studied. The use of Coal-to-PSD ratio of 4:1 for the power generation as against Coal-to-PSD blend ratio of 1:1 resulted to an annual loss of about ZAR6, 461,301.77 ($90,458,224.70) and ZAR123,782.47 ($1,732954.58) WFC and WOFC, respectively.Item Maternal death at Leratong Regional Hospital: a six-year retrospective review, South Africa(University of the Witwatersrand, Johannesburg, 2021-11) Motau, Tumelo Ngaka; Chauke, LawrenceBackground: The aim of the study was to systematically examine the main causes of maternal deaths and contributing factors at Leratong Regional Hospital in order to recommend strategies that can assist in reducing maternal mortality at this level of healthcare. Objectives: The objectives of the study were to: determine the institutional maternal mortality rate at Leratong Regional Hospital between 2012 to 2017, compare the trend (year on year) in the iMMR over the study period, describe the profile of women who died during the period under study, describe the clinical and surgical management of the women who died, and to determine the leading causes of maternal deaths, contributing factors and avoidable factors. Methods: A hospital based retrospective study based on patient clinical records at Leratong hospital. It included all the maternal deaths that occurred at Leratong Regional Hospital during the six-year study period (2012-2017). Results: There was a total of 78 maternal deaths with 32441 live births giving the MMR of 240 per 100 000 live births. However only 74 files could be analysed. The results showed that there was a rise in the maternal mortality rate over a six years period. The majority (70, 94.5%) of the women who died were African, aged between 20-35 years (56, 76%), multigravida (54,73%) with a parity of three or more (23, 31%). Obstetric haemorrhage was the leading cause of maternal death particularly postpartum haemorrhage (11.14%) followed by non-pregnancy related infections, sepsis and eclampsia. Conclusion: Maternal mortality has decreased according to recent confidential enquiry into maternal death in South Africa (2017-2019) However our study did not demonstrate a decline but rather an increase in the maternal mortality rate at Leratong. It showed that most of the maternal deaths were avoidable and the need for urgent interventions in terms of education, improving access to health care facilities, intensifying health care worker skills training and better transport systems between health care facilities is important.Item Interactional Dynamics During Residential Robbery: Victims’ Accounts and Reflections(University of the Witwatersrand, Johannesburg, 2021) Quinn, Caroline; Eagle, GillianSeveral studies highlight the importance of documenting interactional elements of violent crime. While a range of studies focus on perpetrators’ accounts of what transpired during the commission of robberies and other forms of violent crime, there has been a notable oversight in establishing victims’ narratives surrounding such events. This study had a broad over- arching focus on establishing what appeared to either escalate or deescalate violence during a residential robbery from the survivors/victims’ perspective. In addition to this focus, it was further aimed to establish the cognitive appraisals that victims/ survivors reported as salient during the incident, as well as their reported motivations for behaviours they exhibited. Moreover, the study aimed to highlight any socio-demographic features that the victims perceived to be significant in their interaction with perpetrators. An exploratory approach to the research study was undertaken whereby semi-structured interviews were conducted with eight adult South African participants. The data was processed and presented by means of a thematic analysis and contextualized from a primarily realist paradigm. Five superordinate themes were identified across participants’ accounts, including: (1) Comprehending the Nature of the Interpersonal Interaction, (2) Negotiation of Dominance and Submission, (3) Cognitive Processing and Evaluation during the Event, (4) Awareness of Demographic and Socio-Cultural Aspects of the Interchange, and (5) Advice & Post Hoc Observations. These main themes were elaborated through subthemes that aimed to capture nuances across participants’ narratives. The findings suggested that although positioned in a subjugated role participants attempted to moderate or affect the interaction between themselves and the perpetrators. This was mainly achieved by verbally and behaviorally demonstrating compliance in order to mitigate further risk. In addition, participants described more complex ways of responding to perpetrators which appeared to be based on idiosyncratic evaluations of their particular situation. Participants were aware of limited agency but appear to have negotiated some means of retaining or displaying agency within situational constraints. Across all eight participants’ accounts, it was evident that participants acted in accordance with an assessment of their situation and responded in a manner that was perceived to result in ensuring the greatest likelihood of survival. References to race, gender, age and socioeconomic status did not feature as strongly in participants’ accounts as anticipated.Item Financial inclusion in South Africa: An analysis of the financial sector regulatory framework and proposals for reform(2018-09) Duma, Amanda; Kawadza, HerbertAbstract Not Available.Item COVID-19 and health care worker exposure at Chris Hani Baragwanath Academic Hospital(University of the Witwatersrand, Johannesburg, 2021-12-05) Glatt, Sara Chaya; Menezes, Colin; Winchow, Lai ling; Tsitsi, MerikaBackground: Health care workers (HCWs) are at an increased risk of acquiring coronavirus disease 2019 (COVID-19). Appropriate risk assessments and testing are essential to reduce transmission and avoid workforce depletion. Objective: Investigate the risk of COVID-19 infection among HCWs at Chris Hani Baragwanath Academic Hospital who fulfil the Person Under Investigation (PUI) case definition or had exposure to a confirmed COVID-19 contact. Methods: A retrospective review of HCW records was conducted over a two month period. Data collected included demographics, exposure type, risk level, and COVID-19 test result. Frequency distribution tables, bivariate analyses and univariate and multivariate analyses were conducted. Results: Among the 1111 HCWs reviewed, 643 were tested with 35.6% positive results. PUI’s accounted for 62.4% of positive cases. Symptomatic HCWs with no known contact were at a greater risk of infection than those with a patient exposure (p=0.000). Risk of testing positive was higher after a patient exposure (p=0.000) compared to a co-worker contact. Conclusion: There is a higher positivity rate among HCWs than the general population. The presence of symptoms warrants testing. Nosocomial transmission was derived from patient more than co-worker contacts.Item Landscape, Rock Art Recording, Narrative: A Biography of The Harald Pager Archive(University of the Witwatersrand, Johannesburg, 2019) Moodley, Lemishka; Wintjes, JustineIn the early days of the discipline of archaeology, the archaeologist Sir Charles Thomas Newton stated, in a lecture at Oxford University in June 1880, that “the subject-matter of Archaeology is threefold – the Oral, the Written and the Monumental” (Newton 1880, p.3–7). By ‘oral’, he meant expressions of spoken language as a form of patterned communication passed down from the past, which he considered to be as significant as written texts and traces of the built environment. Newton’s statement also resonates with ongoing attempts to make sense of the fragmentary remains of the past by including living sources with links to those remains, often referred to as ‘oral traditions’. I argue that the domain of ‘oral’ could be extended in the contemporary context to refer to the realm of the ‘spoken word’. The spoken word is mobilised in the telling of personal histories of researchers engaged in making sense of the past, consistent with a move towards the study of the production of archaeological knowledge, and the broader context of the history of science. The past, and the investigation of that past, can be easily lost or erased with time, unless it is documented in some form. For as long as I can remember, I’ve had a keen interest in knowing about the world that preceded me. So naturally, movies like Raiders of the Lost Ark (1981), The Mummy (1999), Lara Croft: Tomb Raider (2001), 10 000 BC (2008), The Prince of Egypt (1998), Brother Bear (2003) and many others, fascinated and triggered my overactive imagination. These points of inspiration even prompted many crazy shenanigans and adventures that took place in my back yard. Needless to say, my mother was never impressed because her garden was in constant danger of being destroyed through micro-excavations (as I had to find the treasure I buried the previous evening!). However, it was a Pixar animated film — The Croods (2013) — that recently re-ignited my interest in deeper human history. Despite its status as a relatively mainstream commercial animated film, The Croods sparked my curiosity to find ways to visit the past and bring yesterday’s stories into our lives today. After their cave collapses, the first Crood family has to undertake a journey to find a new home. The father, provider and leader of his pack, recounts multiple stories that urge and caution his children to follow the rules described on the cave wall and to not try anything “new”, or generally be curious for that matter. He sees newness as dangerous, with potentially serious repercussions like death. He prefers for them to dwell in the “safe” compounds of the cave in which they live. He develops “cautionary” narratives through visual means by drawing pictures on the cave walls using pigment and dirt he scoops off the ground. The animated film highlights the ways in which a pictorial expression in the form of rock markings could be enlivened in its original context of performance and story-telling, and, also, the ways in which history is forged through personal experience. The film also prompted me to reconsider the academic realm in which rock art is primarily situated in southern Africa, which is archaeology, and the possible perspectives that other disciplines could bring to bear on these materials, such as art history. My understanding of the reasons why rock art (and its copies) can and should also be considered and studied as an art form, ultimately stems from my own experience in art education. The rock art works made by the San people are encoded with “the history and culture of a society” that is “thousands of years old” and “a testament of the displaced ancient African culture and the San presence in the world” (Solomon 2005). By studying these traces as artworks, researchers, historians and archaeologists are reminded to look at the visual features, but also beyond the physical aspects of the work. They begin to consider the processes that contributed to its making, and the various interpretations and meanings that the work had in its context of production, as well as in its subsequent readings. An examination of the process of knowledge production not only draws attention to the development of artmaking and the manner in which different materials were used to create artworks, but also demonstrates the precarious nature of the meaning of rupestrian imagery. An example of this instability of meaning is evidenced by a body of oral histories relevant to the San context, starting with Joseph Orpen’s documentation (1874) of a mountain Bushman called Qing’s account of the meaning behind particular rock art panels. Thereafter, in 1911, Wilhelm Bleek and Lucy Lloyd produced Specimens of Bushmen Folklore, a book of 87 recorded legends, myths and other traditional stories of the |Xam Bushmen in their now-extinct language (Solomon 2005). These resources integrated the “spoken word” with Bushman ethnographic research and laid the foundation for how we read and write about the art today, and they also provide numerous different ways into the question of interpretation. I have utilised my previous first-hand experience as an intern at the Origins Centre, where Simone Opperman and myself worked under the guidance of Steven Sack and Lara Mallen. In working towards the exhibition titled, The Origins of Walter Battiss: “Another Curious Palimpsest”, we worked closely with the Rock Art Research Institute (RARI), and my interest in rock art and its archive grew immensely. Here, I learned of the Harald Pager archive, which is physically located at RARI. After speaking to my supervisor, Dr Justine Wintjes, and listening to the way in which she briefly recounted the story of Harald Pager, who was an active rock art recorder and researcher during the 1960s and 1970s, I wanted to learn more about the man who seemingly died for his craft. Wintjes mentioned that Pager recorded San rock art in the Drakensberg area along with his wife for many years. The Pagers relied heavily on their personal resources in order to keep the recording and documentation process going, and ended up incurring financial debt. Harald Pager was passionate about archaeology and sought to understand the rock paintings he discovered in his travels across the region, which also included what was then South West Africa (now Namibia). In one of the conversations held in the course of my Masters research, Neil Lee explained that Pager dwelled for months on end in a shelter in order to finish the copies of rock paintings he sought to record. Pager’s adamance and determination, and even his belief that he could change his metabolism, apparently led to ill health while recording rock art in the Brandberg in 1985. He died a short time later in Windhoek (Neil Lee 2018, pers. comm.). 7 Given the scale and meticulousness of Pager’s archive, and in light of the conversations I had about him, it seemed strange that his work and story are engaged with so seldom within academia. Nevertheless, Pager’s vast archive lives on in the storerooms of RARI, and now also in the digital world. His recordings were recently digitised during the course of the South African Rock Art Digital Archive (SARADA) project, which sought to scan and make more accessible the content related to southern African rock art at RARI and other institutional and private archives. With the rapid rate at which technology is developing and progressing, physical archives are being turned into digital databases, while also being supplemented by newly created digital materials. However, like all archives, digital archives are not ‘permanent’. They have their own kind of media-specific fragility. The digital archive also has the potential to become obsolete and demonstrates a different kind of limited lifespan. Although digital files are also not physically present in the same way that a physical copy or photograph is, and “lose” a particular kind of materiality and stability, they gain a virtual presence and potentially greater accessibility. As with the ‘original’ archive of rock art that exists in the landscape, the traditional paper archive and the digital archive represent different kinds of longevity and fragility, and have a complex relationship with each other. While being subject to changes and deteriorations of various kinds, the archive is important as a record of archaeological materials in the landscape, but is also a site where knowledge is produced, and the practice of science is conducted. Thus, I set out to devise a project that would address some of these interests and problems, to find connections between the present and the past, and to focus on ‘process’ across the rock art archive in the broad sense of the term. I also wanted my project to address absences and silences within the archive, embedded within the documents and copies as well as the rock art itself. I approached the archive as a layered domain that extends beyond the strictly ‘documentary’ archive, and adopted a ‘personal histories’ approach as a way of forging connections across that archive. I explain this working strategy in more detail in the ‘Methodology’ section below, but first I explore some of the conceptual elements that frame the project.Item Surgical aortopulmonary shunts - a thirty-seven year experience in a South African tertiary institution(University of the Witwatersrand, Johannesburg, 2019-11) Dladla-Mukansi, Nontobeko Charity; Cilliers, Antoinette; Mammen, Vijay; Vanderdonk, KathyIntroduction: The surgical aortopulmonary shunt is a valuable palliative procedure in the management of congenital heart diseases. There is a paucity of data regarding aortopulmonary shunts in the developing world, including South Africa. Objectives: The primary objective was to describe the demographic, clinical and echocardiographic characteristics of children between ages 0 and 14 years that underwent surgical aortopulmonary shunts. The secondary objectives were to describe trends in aortopulmonary shunt designs, outcomes in terms of morbidity and mortality, progression to definitive surgery and to assess patency of shunts. Material and Methods: A retrospective clinical audit of patient files who underwent an aortopulmonary shunt between 01 January 1980 to 30 December 2016 was undertaken at Chris Hani Baragwanath Academic Hospital (CHBAH) in Soweto, Johannesburg. The study period was divided into 3 stages and for descriptive purposes as follows: 1980-1991 refers to period 1, 1992-2003 refers to period 2 and 2004-2016 refers to period 3. Results: A total of 177 aortopulmonary shunts were done over the 37-year study period. Of these 177 patients, 165 (93.2%) patient files were available. Fifty-six percent of the patients included in the study were male. The majority of patients were from the Gauteng Province (76.8%). The four most common diagnoses across the entire study period were tricuspid atresia (26.0%), pulmonary atresia with VSD (23.7%), tetralogy of Fallot (23.2%) and complex cardiac lesions (16.9%), with no particular trend in the proportion of these diagnoses presenting across this study period. There was no statistical difference between period 1 and 2 (p-value a=0,328) and between period 1 and 3 (p-value b=0,548). The total number of all surgeries done over the entire study period was 2145, of which 8.3% were aortopulmonary shunts. Period 1 had the highest percentage [35 (10.9%)] of aortopulmonary shunts compared to the total number of surgeries performed. There was a decline in the number of aortopulmonary shunts performed over the study periods 1-3. With no statistical difference across periods as shown in table 1 with p-value a and b. Of the different types of aortopulmonary shunts, most patients [157 (88.7%)] had a modified Blalock-Taussig shunt (BTS). The remainder of the shunts included 3 (1.7%) classic BTS, 12 (6.8%) central shunts and 5 (2.8%) unknown BTS. The percentage of modified BTS done increased from 80% in period 1 to 87.3% in period 2 and to 95.2% in period 3. Period 1 had the most complications (28.6%) compared to 11.4% in period 2 and 19.1% in period 3. Sepsis as a complication following surgery increased over the study period from 2.9% in period 1 to 3.8% and 7.9% in periods 2 and 3 respectively. Early mortality was 17.1%, 26.6% and 25.4% from periods 1-3 respectively. Late mortality declined from 17.0% in period 1 to 11.4% and 0% in periods 2 and 3 respectively. Only 37 (20.9%) patients were documented to have further surgery after the initial aortopulmonary shunt. Across all three study periods, no blocked shunts were documented. Conclusions: This study describes the characteristics and outcomes of aortopulmonary shunts over a 37-year period in a tertiary care resource limited low to middle income country setting. The commonest cardiac lesions for which aortopulmonary shunts are performed are tricuspid atresia, pulmonary atresia with VSD, tetralogy of Fallot and other complex cyanotic cardiac lesions. The frequency of aortopulmonary shunts compared to total surgeries has corrective surgery for these cardiac lesions. The modified BTS is the most frequently performed aortopulmonary shunt used for palliative surgery in our setting, which is a similar trend in developed countries. The morbidity and mortality in this study is higher than developed countries, with sepsis being the most common complication. Attention to infection control practises need to be emphasized peri- and post-operatively in our hospitals.