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- ItemOpen AccessGenetics of Waardenburg Syndrome in Africa: A Systematic Review(2025-12-22) Aboagye, Elvis Twumasi; Wonkam, Ramses Peigou; de Kock, Carmen; Dandara, Collet; Wonkam, AmbroiseWaardenburg syndrome (WS) represents a group of genetic conditions characterized by auditory and pigmentation defects. Pathogenic variants in PAX3, MITF, SOX10, EDN3, EDNRB, SNAI2, and KITLG genes have been associated with WS across multiple populations; a comprehensive study of WS in Africa has not yet been reported. We conducted a systematic review of clinical expressions and genetics of WS across Africa. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed, and the study protocol was registered on PROSPERO, the International Prospective Register of Systematic Reviews (2025 CRD420250655744). A literature search was performed on Google Scholar, PubMed, Scopus, Directory of Open Access Journals (DOAJ), Global Index Medicus, African-Wide Information, ScienceDirect, Connecting Repositories (CORE), and the Web of Science databases. We reviewed a total of 15 articles describing 84 WS cases, which showed no gender bias and a mean age at reporting of 17.5 years. Congenital, sensorineural, and profound hearing loss was described in most cases (66.7%; n = 56/84). WS type 2 (WS2), with characteristically no dystopia canthorum, is the predominant subtype (36.9%; n = 31/84). Pathogenic variants in four WS known genes, i.e., PAX3 (13 families), SOX10 (7 families), EDNRB (4 families), and EDN3 (1 family), were reported in Morocco, Tunisia, and South Africa. One candidate gene (PAX8) was described in one family in Ghana. Two non-syndromic hearing loss (NSHL) genes (BDP1 and MYO6) were reported in two separate families in South Africa, suggesting a possible phenotypic expansion. The highest number of WS cases was described in South Africa (38.1%; n = 32/84) and Tunisia (26.2%; n = 22/84). Gene variants were missense (27/43), deletion (7/43), splicing (5/43), nonsense (2/43), indel (1/43), and duplication (1/43), chiefly segregating in an autosomal dominant inheritance mode. There was no functional data to support the pathogenicity of putative causative variants. This review showed that WS2 is the most common in Africa. Variants in PAX3 and SOX10 were the predominant genetic causes. This study emphasizes the need to further investigate in-depth clinical characterization, molecular landscape, and the pathobiology of WS in Africa.
- ItemOpen AccessDevelopment of a Prototype Embedded 3D Printer with Dual Ink-Gel Extrusion Capability(2025-12-12) Van Driel, Adrian; Govender, Reuben A.3D printing has advanced significantly, enabling new applications such as embedded 3D printing for materials that solidify slowly. This method prints liquid materials into a support gel that holds their shape while curing. This project developed the dual ink-gel extruder (DIGEX) to address the limitations in the print volume seen in previous projects and to enable the simultaneous extrusion of material and support gel. Various sub-assemblies and deposition techniques were tested to optimise performance. While DIGEX successfully demonstrated the concept, difficulties remain in scaling for large-format printing, requiring further refinement in hardware, software, and process configurations.
- ItemOpen AccessThe Application of Taguchi Experiments in Developing Gecko-Inspired Dry Adhesive for Macro-Handling Applications(2026-12-12) Nyanga, Lungile; Govender, Reuben A.; Matope, StephenSynthetic dry adhesives have been developed to mimic the gecko’s adhesion using lithography and micro-machining of a mould to cast a suitable elastomer. Previous international studies used nano-manufacturing processes, which are expensive and are not readily available in South Africa. In this study, a simple micro-machining method was used using a three-axis milling machine and Vytaflex 30 to develop an adhesive pad. The Taguchi method to design experiments was used to determine the optimum machining conditions to create micro-wedges. The results show that, although a maximum adhesion pressure of 1,924 Pa was obtained with a preload pressure of 1,323 Pa, the adhesion force produced might not be suitable for macro-handling applications.
- ItemOpen AccessBwanya v Master: A Softening of the Doctrine of Precedent(2024) Osman, FatimaBwanya v Master of the High Court [2021] ZACC 51, 2022 (4) BCLR 410 (CC), 2022 (3) SA 250 (CC) provided the Constitutional Court with the opportunity to reconsider its previous judgment of Volks v Robinson [2005] ZACC 2, 2005 (5) BCLR 446 (CC) and its implications for the inheritance rights of opposite-sex partners. The Court in Bwanya, in a much-anticipated decision, declared the Intestate Succession Act 81 of 1987 and the Maintenance of Surviving Spouses Act 27 of 1990 unconstitutional to the extent that the legislation did not provide for partners in a permanent life partnership in which the partners have undertaken reciprocal duties of support. The article argues that while Bwanya may be distinguishable from Volks, it would be an artificial—rather than meaningful—distinction that seeks to avoid a confrontation with Volks. The Bwanya and Volks cases raise the same substantive issue, being the rights of unmarried partners, and the Court should be applauded for confronting the issue directly rather than skirting the issue through superficial distinctions. Unfortunately, the Court’s approach in confronting and departing from Volks without declaring the previous judgment wrong is confusing and unconvincing. The judgment appears to represent a softening of the doctrine of stare decisis and a shift in the Court’s approach regarding the rights of unmarried parties, as legislative intervention in this area is not forthcoming.
- ItemOpen AccessLeft in Limbo The Status of the Handing Over of the Bride in Customary Marriages Post Sengadi v Tsambo(2025-03-25) Osman, Fatima; Kruger, Sky; Bebington, Micaela Lara; Uranovsky, Jaime LilleenCourts are regularly tasked with determining the validity of a customary marriage using the requirements stipulated in the Recognition of Customary Marriages Act. This entails an assessment of whether certain fundamental rituals and practices occurred. One such ritual that appears frequently in recent jurisprudence is the handing over of the bride to the bridegroom’s family, although courts have differed on whether this is a necessary requirement for a valid customary marriage. In the case of Sengadi v Tsambo, the High Court conceptualised the handing over ritual as an extraneous requirement additional to the Recognition of Customary Marriages Act that could be imposed on an otherwise valid marriage, and ruled it unconstitutional to this extent. This article argues that the High Court's declaration of unconstitutionality, while peculiar for positioning the practice of handing over as extraneous to the statutory provisions, was within its powers, effective without further confirmation, and binding on lower courts within its jurisdiction. Upon appeal, rather than clarifying the matter, the Supreme Court of Appeal did not substantively deal with the High Court’s peculiar conception of handing over and ruled that the High Court should not have pronounced on its constitutionality. In doing so, we argue that the Supreme Court of Appeal may have tacitly overturned the High Court’s declaration of constitutional invalidity.