A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg in fulfilment of the requirements for the degree of Master of Science. Johannesburg, 2018 / The morphological variation between populations is shaped by adaptive responses to prevailing environmental conditions and/or not adaptive stochastic effects. Within-population variation is mainly related to age and sexual dimorphism, as well as temporal and spatial variation in environmental conditions. The aim of this study was to investigate patterns of variation in the skull, mandibles, and dentition in a population of the African four-striped mouse Rhabdomys dilectus chakae. Geometric morphometrics was used to assess the variation related to allometry and age, sexual dimorphism, and the inter-annual variation between specimens collected in different years (1975, and 1994-1997). A review of the literature on the application of geometric morphometrics to rodent morphological variation was conducted and landmark morphometrics were concluded to be the most appropriate methods for the skull and the mandible analyses, with a separate analysis using landmarks and semi-landmarks to analyse the variation of mandibular curves, and outline morphometrics with an Elliptic Fourier analysis of the upper molars. Images of the skull (ventral and lateral view at 5x magnification), mandible (at 6.8x magnification), and the three left upper molars (at 10.5x magnification) were captured using a stereoscopic microscope. Landmarks were digitized on the skull and mandible images, with semi-landmarks digitized on mandible images, and outlines were digitized on molars. Multivariate analysis of variance was used to analyse shape and size variation due to age, sex, and year of sampling and a multivariate regression was used to analyse allometry. A PCA was used to visualize shape variation, and boxplots of log-centroid size to visualize size variation between age classes, sexes, and years of sampling. Shape variation was significantly predicted by age and year of sampling, while size was significantly predicted by age, sex, and year of sampling. Size significantly contributed to shape variation, although size alone did not appear to explain much of the variation present. Most age-related variation in shape was due to differences between the first three age classes and age class IV, while size increased with increased age (i.e. growth). Males were larger than females although no sexual shape dimorphism was evident between sexes. Typical of species with male-male competition, Rhabdomys dilectus chakae demonstrated sexual size dimorphism; larger males have greater mating opportunities. Specimens from 1994 and 1997 had more variable shapes and were consistently smaller than those collected in 1975, 1995 and 1996, except for dentition where these latter specimens were smaller than those collected in 1994 and 1997. Annual variation in morphology may be a plastic response to prevailing local climatic conditions (i.e. rainfall and temperature), Masters Dissertation Candice Neves iv resulting in annual variation in diet, affecting the skull and dentition. Further studies should consider more populations in the species to assess the generalizability of the findings, particularly annual variation, and to consider spatial variation across the distribution of a population. / GR2019

Submitted in partial fulfillment for the requirement for the degree of MSc (Nursing) in the Department of Nursing Education in the Faculty of Health Sciences at the University of Witwatersrand / Single parent family structure is becoming prevalent in South Africa as a result of divorce or separation. Venda, as part of South Africa is not immune from divorce, however traditional values have an impact on this issue amongst Venda women. Venda like other African nations that value their culture, is in transition to Westernisation. Marriage is greatly valued and is viewed as an avenue for security, social and emotional fulfillment. Girls are raised to believe that the dignity of the mistress of the house demands concealment of dissension within it. Venda women are expected to stay in and preserve their marriage no matter how difficult it becomes. Modern women who are increasingly better educated and more conscious of their rights, often feel they must challenge their husbands and may seek divorce when the marriage is intolerable. Although women in Venda are seeking divorce more frequently, conflict arises between cultural background and Westernisation. Divorced women are not acceptable, regarded as failures and are denigrated by society. Due to the kind of issues that divorce women in Venda are faced with, a survey assessing their coping skills was conducted on 50 divorced women with children and working in an industrial area at Shayandima in Venda. The demographic questionnaire and translated “Ways of Coping” scale (Revised) by Folkman and Lazarus (1984) as adapted for the purpose of this study was used. The results of the study reflected the different kinds of coping mechanisms used, i.e denial, avoidance, regression, counterphobia, rigidity, projection, self - destructive behavior, inventive behavior and dependency. Most of the women exhibited symptoms of depression, and were not aware of their mental condition. / WHSLYP2016

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No / After an observer adapts to a moving stimulus, texture within a stationary stimulus is perceived to drift in the opposite direction¿the traditional motion aftereffect (MAE). It has recently been shown that the perceived position of objects can be markedly influenced by motion adaptation [1] and [2]. In the present study, we examine the selectivity of positional shifts resulting from motion adaptation to stimulus attributes such as velocity, relative contrast, and relative spatial frequency. In addition, we ask whether spatial position can be modified in the absence of perceived motion. Results show that when adapting and test stimuli have collinear carrier gratings, the global position of the object shows a substantial shift in the direction of the illusory motion. When the carrier gratings of the adapting and test stimuli are orthogonal (a configuration in which no MAE is experienced), a global positional shift of similar magnitude is found. The illusory positional shift was found to be immune to changes in spatial frequency and to contrast between adapting and test stimuli¿manipulations that dramatically reduce the magnitude of the traditional MAE. The lack of sensitivity for stimulus characteristics other than direction of motion suggests that a specialized population of cortical neurones, which are insensitive to changes in a number of rudimentary visual attributes [3], may modulate positional representation in lower cortical areas.

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Two refinement techniques to generate solution adaptive meshes have been developed. Both techniques utilize arbitrary polyhedra (general elements) to constrain the propagation of refinement. A face-based approach that produces isotropic refinement and a combined element- and edge-based approach that produces anisotropic refinement are presented. Refinement is triggered through sensors that use a shock detection algorithm or error estimation based on the smoothness of the reconstructed solution variables. The basic algorithms as well as specific implementation issues are presented. The advantages and disadvantages of the different methods are discussed and illustrated through a set of synthetic and realistic test cases. It is shown that general elements can be employed effectively in solution adaptive meshes generated using refinement.

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