UWCScholar
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Towards a suitable regulatory framework for the effective performance of municipalities in South Africa
(Universty of the Western Cape, 2025) Stevens, Curtly Keagan; Steytler, Nicolaas
This thesis explores whether and how the regulatory framework for local government in South Africa is hampering the ability of municipalities to discharge their constitutional mandate. The study specifically explores whether the phenomenon of over-regulation has manifested itself in South Africa, and what steps can be taken to address it. Claims of over-regulation and poorly designed rules are not new in regard to municipalities. However, until now, scholars in South Africa have often mentioned misgivings about rules, but there is no empirical evidence to back them up, particularly in the context of municipalities. The study begins by reviewing the comprehensive literature on decentralisation and regulatory design, which includes law-making, and finds that no universal model exists for designing a regulatory system applicable to local government. Much of the current literature focuses on general law-making principles without direct link to local government. The study further finds that several regulatory pathologies documented in the literature, such as duplication and complexity (cumulative load of laws and costly regulatory systems that do not consider the capacity constraints of regulators), have all manifested themselves within local government, particularly in Australia and South Africa. With particular reference to South Africa, the study examines the evidence and arguments by means of desktop analysis and empirical data gathered through open-ended interviews. In South Africa, various initiatives have been taken to address the pathologies above by government, including the courts. The study, however, establishes that these initiatives have failed to yield any results in the absence of a clear guiding framework and the institutions necessary to ensure implementation.
High-quality genome assembly and annotation of Thalassiosira rotula (synonym of Thalassiosira gravida)
(Nature Research, 2025) Trindade Marla; Di Costanzo F; Di Marsico M
Diatoms are unicellular eukaryotic microorganisms thriving in most aquatic environments thanks to the expression of biosynthetic pathways for secondary metabolites involved in defence and adaptation to environmental changes. The sequencing of the transcriptome of the cosmopolitan diatom Thalassiosira rotula Meunier 1910 (synonym of Thalassiosira gravida Cleve 1896) and of the metagenome of its associated microbiome revealed the presence of biosynthetic pathways synthesising molecules and compounds useful for the algae survival and with potential biotechnological applications. Here we present the genome of a Neapolitan T. rotula strain, which is 672 Mbp in size due to a high proportion of repetitive elements (63.59%) and segmental duplications (14%), while the number of predicted genes resulted to be comparable to that of smaller diatom genomes. DNA methylation was predominantly located in transposable elements.
Flexible feature engineering using a network flow approach
(Universty of the Western Cape, 2024) Bodenstein, Gerhardus; Blignaut, Renette
Feature engineering, a critical part of the data preparation and exploration phase in predictive modelling, involves transforming predictor variables to enhance interpretability and better understand their relationship with the response variable. In some cases, it also offers automatic handling of outliers and missing values. Many machine learning and data mining techniques perform better with discretised continuous variables or clustered levels of categorical variables, making feature engineering essential for improving the accuracy and robustness of predictive models. Furthermore, the feature engineering process often needs to incorporate business, operational, or best-practice constraints applicable to the final transformed predictor variables or newly created features. This thesis addresses two significant challenges in feature engineering. The first is the supervised discretisation of continuous predictors, which involves partitioning a predictor's domain into disjoint intervals while preserving a specified trend in the relationship with the response variable and adhering to side constraints.
Genome-wide characterization of DREB transcription factors in Medicago truncatula: Insights into their roles in development and abiotic stress response
(Elsevier Inc, 2025) Ndiko, Ludidi; Haddoudi, Loua; Ayadi, Mariem
Dehydration-responsive-element binding (DREB) proteins play a crucial role in drought, salt, and environmental stress tolerance. In this study, we identified and annotated fifty-four DREB genes from the Medicago truncatula genome. These genes were analyzed at the molecular level, focusing on gene classification, genomic organization, phylogeny, synteny, structural features, and expression profiles. Phylogenetic analysis revealed that MtDREB proteins are categorized into six subgroups (A1–A6), with highly conserved motif compositions among them. Expression profiling showed that MtDREB genes are differentially expressed in various plant organs and under abiotic stresses (cold, salinity, and dehydration), with 30 % exhibiting high expression during flowering and development. Data from RNA-seq and microarrays demonstrated that 76 % of MtDREB genes are differentially expressed under at least one stress condition, indicating their involvement in various signaling pathways activated by abiotic stresses. Notably, MtDREB05, primarily induced under osmotic stress, appears to be a promising candidate for improving abiotic stress tolerance. These findings will enhance our understanding of the DREB family and aid in functional validation of DREBgenes in M. truncatula and related forage species.
BRAF p.V600E-negative langerhans cell histiocytosis associated with a periapical cyst: a case presentation with broad review of the differential diagnosis and disease pathophysiology
(Springer, 2025) Odendaal, Anneze; van Rensburg, Leon Janse; Afrogheh, Amir H
Background: Langerhans cell histiocytosis (LCH) rarely presents in the oral and maxillofacial region, and while isolated and small collections of Langerhans-type cells have been found in periapical cysts, there have been no reported cases of LCH arising in periapical cysts. Methods: A 58-year-old female presented with isolated erythematous dry skin lesions and a radiolucent lesion of the anterior maxilla. Microscopic examination of the enucleation specimen revealed a periapical cyst with large collections of atypical cells with grooved folded nuclei with eosinophils consistent with LCH. Immunohistochemistry (IHC) was performed to confirm the diagnosis. BRAF mutation status was evaluated with the BRAF p. V600E antibody and the automated real-time PCR-based Idylla™ assay, capable of qualitative detection of 5 mutations in codon 600 of the BRAF gene. Results: The LCH cells were positive for S100, CD1a, and Langerin (CD 207) and negative for BRAF p. V600E mutations. Ki-67 was 45%. Conclusion: The association of LCH with a periapical cyst could be explained by the active surveillance and migration of neoplastic Langerhans-type cells in blood to the site of apical chronic inflammation, in a patient with LCH. Careful attention to morphologic features in conjunction with Langerin IHC, helps exclude other closely-related dendritic tumours. BRAF p. V600E testing, ideally with real-time PCR assays, can help identify patients who may benefit from BRAF inhibitor therapies. New generations of sequencing that cover a large panel of genetic alterations beyond the frequent BRAF p. V600E mutations (e.g. rare in-frame BRAF deletions), could provide valuable information about the extent, prognosis and treatment of LCH patients. © The Author(s) 2025.