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Item Lock-out, lock-in, and networked sovereignty: resistance and experimentation in Africa's trajectory towards AI(Brazilian Institute of Information in Science and Technology, 2024) Gagliardone, IginioThe conception of digital sovereignty has been associated, especially in the early stages of the diffusion of the Internet, with efforts to keep specific data and information outside of a state’s jurisdiction. AI sovereignty responds to an almost opposite logic, indicating the ability of a state to access and make use of data that are produced within its jurisdiction. These two strategies –which I refer to as lock-out and lock-in sovereignty –share some common roots (e.g. the attempt to protect and enhance specific cultural attributes recognised as important by a national community), but they also point to different technical, economic, and political characteristics needed to enforce one or the other type of sovereignty. The article examines key elements that set these concepts, and their implementation, apart and how they intersect with both existing and potential articulations of national sovereignty in Africa. In particular it opposes a negative –and still pervasive –definition of sovereigntyapplied to African states, based on the Westphalian ideal and “measuring the gap between what Africa is and what we are told it ought to be” (Mbembe 2019, p.26); and the possibilities disclosed by re-appropriating practices of “networked sovereignty” (Mbembe, 2016).Item Precipitation gradients drive high tree species turnover in the woodlands of eastern and southern Africa(Wiley, 2023-07) Davies, Robert W.; Ryan, Casey M.; Harrison, Rhett D.; Dexte, Kyle G.; Ahrends, Antje; te Beest, Mariska; Benitez, Lorena; Brade, Thom K.; Carreiras, Joao M. B.; Druce, Dave J.; Fayolle, Adeline; Finckh, Manfred; Godlee, John L.; Gonclaves, Francisco M.; Grundy, Isla M.; Hoche, T.; Holdo, Ricardo M.; Makungwa, Steve; McNicol, Iain M.; Mograbi, Penelope J.; Muchawona, Anderson; Muhate, Aristidies; Muledi, Jonathan; Pritchard, Rose; Revermann, Rasmus; Ribeiro, Natasha S.; Siampale, Abel; Staver, A. Carla; Syampungani, Stephen; Williams, Mathew; Swemmer, Anthony M.; Edwards, David P.Savannas cover one-fifth of the Earth’s surface, harbour substantial biodiversity, and provide a broad range of ecosystem ser-vices to hundreds of millions of people. The community composition of trees in tropical moist forests varies with climate, butwhether the same processes structure communities in disturbance-driven savannas remains relatively unknown. We investigatehow biodiversity is structured over large environmental and disturbance gradients in woodlands of eastern and southern Africa.We use tree inventory data from the Socio-Ecological Observatory for Studying African Woodlands (SEOSAW) network, cov-ering 755 ha in a total of 6780 plots across nine countries of eastern and southern Africa, to investigate how alpha, beta, andphylogenetic diversity varies across environmental and disturbance gradients. We find strong climate-richness patterns, withprecipitation playing a primary role in determining patterns of tree richness and high turnover across these savannas. Savannaswith greater rainfall contain more tree species, suggesting that low water availability places distributional limits on species,creating the observed climate-richness patterns. Both fire and herbivory have minimal effects on tree diversity, despite theirrole in determining savanna distribution and structure. High turnover of tree species, genera, and families is similar to turnoverin seasonally dry tropical forests of the Americas, suggesting this is a feature of semiarid tree floras. The greater richness andphylogenetic diversity of wetter plots shows that broad-scale ecological patterns apply to disturbance-driven savanna systems.High taxonomic turnover suggests that savannas from across the regional rainfall gradient should be protected if we are tomaximise the conservation of unique tree communities.Item Computer-based cognitive training for cognitive development of alcohol-exposed children in South Africa: a feasibility randomised control trial(Sage Publications, 2023) Louw, Jacobus; van Heerden, Alastair; Broodryk, Mandi; White, Liska; Olivier, Leana; Tomlinson, MarkChildren exposed to alcohol in utero may suffer from cognitive and physical sequelae. The most impactful damage in terms of daily functioning is to higher order cognitive functions involved in planning and goal-directed behaviour, referred to as executive functions. Cognitive training interventions are used as a remedial tool for executive function deficits but require implementation by professionals. For the South African context, where resources are limited, a tablet computer-based cognitive training game was developed. This study aimed to establish the feasibility of implementing and evaluating this intervention in South Africa for children exposed to alcohol prenatally. This was a three-arm feasibility randomised control trial comparing an alcohol exposed intervention arm, to an alcohol exposed control arm, and a non-exposed normative arm. Arm allocation was based on self-reported maternal alcohol use during a structured interview. To assess feasibility, we evaluated participant recruitment and barriers to implementation. Executive functions were measured at baseline and following intervention to evaluate the preliminary impact of the intervention. No significant differences were found between the three arms on the post-intervention assessments. The retention rate was acceptable for a randomised control trial; however, there was significant variance in the length of time spent playing the game overall. The majority of participants learned to play the game quickly and progressed through the difficulty levels. In conclusion, a full randomised control trial using the recruitment, randomisation and implementation method would be suitable in the South African context. The statistical outcomes of this trial do not support a full-scale randomised control trial of this intervention.Item Morphometry of the patellar tendon using a simple tracing method: a gold standard for anterior cruciate ligament reconstruction(Korean Association of Anatomists, 2023-06) Latiff, Sabiha; Olateju, Oladiran IbukunoluThe anterior cruciate ligament (ACL) is mostly damaged in sporting activities. To reconstruct the damaged ACL, a patellar tendon (PT) is often the most preferred graft due to its fast healing and bone integration i.e. bone-patellar tendon-bone graft. Suitability of the PT often depends on the morphometric profile of the tendon. This study reported on the harvestable surface area (SA) of the tendon using a simple tracing method. The PT of 79 adult formalin–fixed cadavers of South Africans of European Ancestry were dissected, and the margins of the PT were traced on a wax paper before the tracings were scanned. The SA, straight proximal width (SPW), curved proximal width (CPW), straight distal width (SDW), curved distal width (CDW) and length of tendon (LOT) from the digitized image of the PT was measured. In addition, the length of the lower limbs was measured to normalize the measurements. The results showed no significant side differences, and the measurements were not sexually dimorphic. A strong correlation was reported for SA vs. LOT, SPW vs. CPW and SDW vs. CDW for both sexes and sides. The presented morphological profile provides additional information on the usability of the graft and with respect to healing and recovery.Item Clinical characteristics and one-year all-cause mortality outcomes in Africans with dilated cardiomyopathy(Elsevier, 2023) Tsabedze, Nqoba; Mpanya, Dineo; Bailly, Claude; Nel, Samantha; Grinter, Sacha; Ramsay, Michele; Krause, Amanda; Wells, Quinn; Manga, PravinAims: Dilated cardiomyopathy (DCM) is a common cause of heart failure in sub-Saharan Africa (SSA). The affected individuals present with new-onset heart failure with reduced ejection fraction and no identifiable primary or secondary aetiology. We aim to describe the clinical characteristics of participants with heart failure of unknown origin. Methods: We screened 161 participants with heart failure of unknown origin and prospectively excluded primary and secondary causes of DCM. All study participants were subjected to laboratory biochemical testing, echocardiography, cardiovascular magnetic resonance (CMR) imaging and invasive coronary angiography. Results: The study comprised 93 participants with a mean age of 47.5 SD 13.1 years. Forty-six (56.1%) participants had evidence of late gadolinium enhancement (LGE) on imaging, and LGE was visualised in the mid wall in 28 (61.0%) of these participants. After a median duration of 13.4 months [interquartile range (IQR): 8.8–28.9 months], 18 (19%) participants died. Non-survivors had a higher median left atrial volume index (44.9 mL/m2 (IQR: 34.4–58.7) compared to survivors [32.9 mL/m2 (IQR: 24.5–47.0), p = 0.017)]. The rate of all-cause rehospitalisation was 29.3%, of which 17 of the 22 re-hospitalisations were heart failure related. Conclusion: Dilated cardiomyopathy in Africans primarily affects young males. In our cohort, this disease was associated with an all-cause mortality of 19% in one year. In SSA, large multicenter studies are required to investigate this disease’s pathogenesis and outcomes.Item Switching from Sucrose-Formulated rFVIII to Octocog Alfa (BAY 81-8973) Prophylaxis Improves Bleed Outcomes in the LEOPOLD Clinical Trials(Dove Medical Press Limited, 2023-06) Mahlangu, Johnny; Kenet, Gili; Moulton, Thomas; Wicklund, Brian M.; Ahuja, Sanjay P.; Escobar, MiguelIntroduction: Previous clinical trials established the efficacy and safety of sucrose-formulated recombinant factor (F) VIII (rFVIIIFS/Kogenate FS®/Helixate FS®) and octocog alfa (BAY 81–8973/Kovaltry®; LEOPOLD trials). Aim: To report the results of a post hoc subgroup analysis assessing efficacy and safety outcomes in patients with hemophilia A who were receiving rFVIII-FS prior to enrolling into the LEOPOLD I Part B and LEOPOLD Kids Part A clinical trials and switching to octocog alfa. Methods: LEOPOLD I Part B (NCT01029340) and LEOPOLD Kids Part A (NCT01311648) were octocog alfa Phase 3, multinational, open-label studies in patients with severe hemophilia A aged 12–65 years and ≤12 years, respectively. Annualized bleeding rate (ABR) was the efficacy endpoint for both studies. Safety endpoints included adverse events (AEs) and development of FVIII inhibitors. Results: Of the 113 patients in both LEOPOLD trials, 40 (35.4%) patients received rFVIII-FS prophylaxis pre-study and had data available for pre-study total ABR. In LEOPOLD I Part B (n = 22, 35.5%), median (Q1; Q3) total ABR decreased from 2.5 (0.0; 9.0) pre-study to 1.0 (0.0; 6.8), and from 1.0 (0.0; 6.0) pre-study to 0.0 (0.0; 6.02) in LEOPOLD Kids Part A (n = 18, 35.3%). Octocog alfa was well tolerated, and no patients had drug-related serious AEs or inhibitors. Conclusion: Treatment with octocog alfa prophylaxis appeared to have a favorable risk–benefit profile compared with rFVIII-FS and thus could be an effective and improved alternative strategy for individualized treatment for children, adolescent and adult patients with severe hemophilia A currently on rFVIII-FS treatmentItem An assessment of the artificial modelling elements approach to the pressure-driven analysis of water distribution networks(IWA Publishing, 2023) Tanyimboh, Tiku T.; Sivakumar, P.; Gorev, Nikolai B.; Nivedita, S.; Suribabu, C. R.; Gupta, RajeshEPANET 2.2 is a newly introduced upgraded version of EPANET 2 that can be used for both pressure-driven analysis (PDA) and demanddriven analysis (DDA) of water distribution networks. Moreover, it has certain limitations concerning the minimum and required pressure head parameters used for PDA, which leads to inaccurate simulation results. Another limitation of the PDA option of EPANET 2.2 is its inability to simultaneously consider pressure-dependent demands with pressure-independent fire demands. In this article, the reason for the spurious convergence is identified, and it is shown that the spurious convergence of EPANET 2.2 can be addressed by extending the energy balance convergence criterion to include the virtual demand links employed in the EPANET 2.2 formulation of PDA. On the other hand, interest in the methods that use artificial modelling elements in EPANET 2 for PDA is increasing rapidly. The implementation of the method presented in this paper (termed the alternative PDA approach) allows an extended period simulation of large networks with complex demand patterns, multiple tanks, reservoirs, pumps, valves, and thousands of pipes. Two benchmark networks and two real-world networks were analysed by both the alternative PDA approach and EPANET 2.2 and the results were compared.Item Dopamine Transporter Deficiency Syndrome (DTDS): expanding the clinical phenotype and precision medicine approaches(MDPI, 2023-06) Waddington, Simon N.; Ng, Joanne; Barral, Serena; Kurian, Manju A.Infantile parkinsonism-dystonia due to dopamine transporter deficiency syndrome (DTDS) is an ultrarare childhood movement disorder caused by biallelic loss-of-function mutations in the SLC6A3 gene. Advances in genomic analysis have revealed an evolving spectrum of SLC6A3-related neurological and neuropsychiatric disorders. Since the initial clinical and genetic characterisation of DTDS in 2009, there have been thirty-one published cases with a variety of protein-truncating variants (nonsense variants, splice-site changes, and deletions) and missense changes. Amino acid substitutions result in mutant proteins with impaired dopamine transporter function due to reduced transporter activity, impaired dopamine binding, reduced cell-surface expression, and aberrant posttranslational protein modification with impaired glycosylation. In this review, we provide an overview of the expanding clinical phenotype of DTDS and the precision therapies in development, including pharmacochaperones and gene therapy.Item Adaptive-Mode PAPR Reduction Algorithm for Optical OFDM Systems Leveraging Lexicographical Permutations(MDPI, 2023-06) Niwareeba, Roland; Cox, Mitchell A.; Cheng, LingIn direct current optical orthogonal frequency division multiplexing (DCO-OFDM) systems, the high peak-to-average power ratio (PAPR) has been a significant challenge. Recently, lexicographical symbol position permutation (LSPP) using random permutations has been introduced as an efficient solution to reduce high PAPR. In this paper, we aim to evaluate the effectiveness of LSPP by comparing both adjacent and interleaved lexicographical permutation sequences with random lexicographical permutation sequences. Our findings demonstrate that random permutation yields superior PAPR reduction performance results when compared to adjacent and interleaved permutation. However, in scenarios with a limited number of sub-blocks, the use of adjacent and interleaved permutation becomes more favorable, as they can eliminate the possibility of generating identical permutation sequences, a drawback of random permutation. Additionally, we propose a novel algorithm to determine the optimal number of candidate permutation sequences that can achieve acceptable PAPR reduction performance while adhering to computational complexity constraints defined by the system requirements.Item Advancing HIV Drug Resistance Technologies and Strategies: insights from South Africa’s Experience and Future Directions for Resource-Limited Settings(MDPI, 2023-06) Steegen, Kim; Hans, Lucia; van Zyl, Gert U.; Claassen, Mathilda; Khan, Aabida; Pillay, Melendhran; Govender, Subitha; Bester, Phillip A.; van Straaten, Johanna M.; Kana, Vibha; Cutler, Ewaldé; Kalimashe, Monalisa N.; Lebelo, Ramokone L.; Moloi, Mokopi B. H.Monitoring of HIV drug resistance (HIVDR) remains critical for ensuring countries attain and sustain the global goals for ending HIV as a public health threat by 2030. On an individual patient level, drug resistance results assist in ensuring unnecessary treatment switches are avoided and subsequent regimens are tailored on a case-by-case basis, should resistance be detected. Although there is a disparity in access to HIVDR testing in high-income countries compared to low- and middle-income countries (LMICS), more LMICs have now included HIVDR testing for individual patient management in some groups of patients. In this review, we describe different strategies for surveillance as well as where HIVDR testing can be implemented for individual patient management. In addition, we briefly review available technologies for HIVDR testing in LMICs, including Sanger sequencing, next-generation sequencing, and some point-of-care options. Finally, we describe how South Africa has implemented HIVDR testing in the public sector.