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Acceptance of synthetic speech in South African languages: A comparative study of Afrikaans, isiZulu, and Sepedi in healthcare contexts

(2025-11) Louw, Johannes A; Wilken, Ilana

While text-to-speech technologies have made significant advances in recent years, ques tions remain about how synthesised speech is accepted in culturally and linguistically di verse settings such as South Africa. This study explores how South Africans perceive synthetic speech in comparison to human recorded speech across three official languages: Afrikaans, isiZulu, and Sepedi, with healthcare as the application context. Using a blind and randomised listening test, 65 participants rated audio prompts across four acceptance metrics: trust, knowledgeability, lik ability, and relatability. Statistical analysis us ing the Wilcoxon signed-rank test revealed no significant difference between natural and syn thesised speech perception among Afrikaans speakers. However, low participation rates pre vented meaningful analysis of speech percep tion for isiZulu and Sepedi speakers. When combining data from all participants, a medium effect size favouring natural speech was ob served, though this difference was not statisti cally significant. These findings suggest that synthetic speech adapted from natural recordings may be suit able for certain applications in South Africa, though larger and more linguistically represen tative samples are needed to confirm these re sults.

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B31D-09: Phytoplankton community composition in inland waters from airborne and satellite hyperspectral data

(2025-12) Sharp, SL; O’Shea, RE; Guild, LS; Cortés, A; Forrest, AL; Kravitz, J; Lain, L; Mpapane, S; Mudzielwana, R; Smith, Marie E

This presentation covers the basis of aquatic food webs, loss of biodiversity and the negative impact on the ecosystem.

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Photonic-biosensing towards drug-resistant tuberculosis diagnosis

(2025-07) Chauke, Sipho H; Tjale, Mabotse A; Maphanga, Charles P; Dube, F; Ombinda-Lemboumba, Saturnin; Mthunzi-Kufa, P

Early detection and treatment of tuberculosis (TB) remain key strategies to reduce transmission and disease progression. However, this is hampered by time-consuming, insensitive diagnostic methods, particularly for the detection of drug-resistant forms and in patients with human immunodeficiency virus infection (HIV). Several genes, such as the RpoB and InhA genes, contain mutations that are responsible for drug resistance. This study aimed to use an SPR-based biosensor platform to detect RpoB and InhA genes. DNA probes, specific to RpoB and InhA, were used as biorecognition elements to capture the corresponding target DNA sequences. The RpoB and InhA gene-specific thiolated DNA probes were immobilized on a gold-coated glass substrate before the target DNA was introduced for detection. As a negative control, a non-specific target to both genes was used to confirm the binding of the specific target. The shifts in the resonance angles indicated the binding properties associated with DNA hybridization between the specific target and the capture probe. The results obtained from this study demonstrated the use of a simple SPR setup and its potential for identifying genes associated with drug-resistant TB.

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Valorization of invasive water hyacinth for nutrients removal from eutrophic waterbodies and biochar production

(2025-10) Tshikovhi, NA; Mudzanani, K; Phadi, T; Masindi, Vhahangwele; Foteinis, S

Among many plights caused by eutrophication, the overabundance of algae and aquatic plants constitutes external pressures and stresses mounted on aquatic ecosystems. Of the aquatic plants known to infest rivers and dams, water hyacinth is considered the most problematic due to its invasiveness that disrupts waterways and pose detrimental environmental and health risks. This non-native (alien or exotic) species is already impairing aquatic ecosystems in South Africa, while vast harvested quantities, currently considered a waste, further exacerbate the problem. However, when viewed under the circular economy and waste valorization lenses, water hyacinth can be an important resource. Here, this was used for biochar production, by examining different temperatures, with 500 °C providing high carbon content. HR-SEM-EDS, HR-TEM-EDS, and XRF revealed varying biochar compositions, all enriched with notable phosphorus levels. This reflects the highly degraded state of freshwater bodies in South Africa since water hyacinth is a known phosphorus hyperaccumulator. Thermal analysis revealed that the raw water hyacinth mainly (96 %) comprises water, while weight losses for biochar at 167–990 °C correspond to moisture and volatile matter removal. Finally, biochar yield decreased from 32.5 % at 300 °C to 24.7 % at 700 °C, confirming progressive devolatilization and carbon enrichment at higher temperatures. Overall, results suggest that water hyacinth, an invasive species that wreaks havoc in aquatic ecosystems, can be sustainably managed to improve freshwater quality through nutrients removal and then used for biochar production. The produced biochar could be a good candidate for (waste)water treatment (adsorption) and particularly soil amelioration, given its high phosphorus content, and carbon dioxide removal (CDR) capabilities.

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Assessment of the interventions required to enable participation of South African SMMEs in renewable energy Global Value Chains

(2025-10) Rakaibe, Tshwanelo K; Mbam, Vuyo

In the second quarter of 2022, the then Small Enterprise Development Agency (SEDA) reported that small, micro, and medium enterprises (SMMEs) accounted for 59% of total employment in South Africa. Some of these enterprises are attempting to, and or aspire to, localise the production and assembly of components in the renewable energy value chains given the increasing demand for renewable energy in South Africa, which can contribute to the reduction of unemployment, poverty and inequality. However, they do so in the context of these components being manufactured in global value chains dominated by east-Asian countries, particularly China. This paper provides a detailed analysis of how South African SMMEs can participate in the renewable energy global value chains (GVCs), highlights the benefits that SMMEs can derive by participating in GVCs and the challenges that they, in general, encounter when trying to participate in GVCs. The insights presented herein are drawn from a review of international literature and a survey questionnaire that was sent out to South African SMMEs involved in the renewable energy industry. Drawing from the literature review and SMME survey responses, a case is made for why it would be beneficial for South African SMMEs to be integrated into renewable energy GVCs and, most importantly, what actions would need to be taken by both the SMMEs and the government - whose responsibilities would include, among others, creating an enabling and supportive environment for SMME integration into GVCs. The interventions recommended in this paper are aligned with the South African Renewable Energy Masterplan (SAREM) vision of industrialising the renewable energy value chain in South Africa to enable participation in the energy transition, serve the needs of society and contribute to economic revival. Furthermore, these interventions relate directly to the SAREMs objectives, such as “growing the industrial capacity in the renewable energy and battery storage value chain”; “building the capabilities needed for the industry”, and “contributing to a just energy transition” in which SMMEs could play an integral role in democratising the energy sector, creating employment and contributing to economic growth.