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Hotspot detection in spatial analysis identifies geographic areas with elevated event rates, facilitating more effective policy interventions aimed at reducing such incidents. In the current literature, several methods have been used to detect hotspots such as measures for local spatial association and spatial scan methods. However, the performance of these methods is limited for small-scale hotspots as well as spatial domains where the number of areas is small. In this work, we propose a new approach, making use of the Discrete Pulse Transform (DPT) to decompose spatial lattice data along with the multiscale Ht-index and the spatial scan statistic as a measure of saliency on the extracted pulses to detect significant hotspots. The proposed method outperforms the well-used local Getis-Ord statistic in a simulation study, especially on small-scale hotspots. The method is also illustrated on South African COVID-19 cases and South African crime data. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the root and canal morphology of mandibular second molars, including anatomical variations, in a Black South African population using two classification systems. Methods: Cone-beam computed tomography images of 386 teeth were evaluated. The number of roots and canal configurations were categorized using the classifications of Vertucci (with modifications by Sert and Bayirli) and Ahmed et al. (including the modified Melton classification). Relationships between variables were assessed using Fisher’s exact test (P < 0.05). Results: Mandibular second molars were predominantly two-rooted (91.7%). The majority of teeth had three canals including Type IV mesial (41.2%) and Type I (75.1%) distal (Ahmed et al. configuration: ²MDM M² D¹). Three or more canals were present in almost one-fifth of mesial (n = 72/386, 18.6%) and a small number of distal (n = 21/386, 5.4%) roots. Males displayed additional canals more frequently in the distal root (P = 0.02). C-shaped anatomy was found in 5.7%. Among the C-shapes, the most common was Melton’s Type III in the coronal (50%), middle (81%) and apical (72%) thirds. Conclusion: In this population, mandibular second molar teeth exhibited diverse morphology, which would have clinical significance for endodontic practitioners. The Ahmed et al. classification provided a better description than the Vertucci classification. [ABSTRACT FROM AUTHOR]

This study investigated the root and canal morphology of maxillary second molars in a Black South African population using high‐resolution cone‐beam computed tomography. In total, 386 maxillary second molar teeth were evaluated and described according to the classifications of Vertucci (with the additions of Sert and Bayirli), as well as Ahmed et al. Root number, fusions and canal morphology were recorded. Relationships between morphology, sex and age were assessed using Fisher's exact test (p < 0.05). Maxillary second molars were predominantly three‐rooted (96.1%), with root fusion observed in 14%. No relationships between sex, age and canal morphology were found. Additional canals were observed in 67.4% of mesiobuccal roots. The Ahmed et al. classification provided a better overall description of the morphology. In this population, maxillary second molar teeth exhibited a diversity of root and canal morphology. Complex variations may render endodontic management more difficult and increase the possibility of missed anatomy. [ABSTRACT FROM AUTHOR]

Apartheid laws resulted in racial residential segregation that became entrenched into the urban morphology of South Africa. When apar-theid ended in the 1990's, the new South African democratic government was resolved to bring about social and spatial justice, address inequalities and promote social cohesion. To determine progress towards racial residential integration, aspatial indices of segregation are widely employed despite their shortcomings and limi-tations. This study employs two spatial indices of segregation: the spatial information theory index and the spatial exposure/isolation index in order to measure and quantify the levels of racial residential segregation that individuals living in Gauteng province (South Africa) would experience on average within radii of 500m, 4km and 8km of their respective residential locations. The analysis is based on the 1996, 2001 and 2011 Census data. The results indicate that the levels of racial residential segregation have steadily declined between 1996 and 2011. The levels of exposure of Whites to Black Africans continue to increase while the levels of exposure of Black Africans to Whites have remained unchanged over the same period. These observations are true for the different geographic scales (i.e. within radii of 500m, 4km and 8km) of analysis considered in this study. [ABSTRACT FROM AUTHOR]