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>Magister Scientiae - MSc / Microorganisms of the class Actinobacteria and domain Archaea are interesting from a biotechnological perspective owing to their metabolic attributes as producers of secondary metabolites and resilience under harsh environmental conditions respectively. Lake Magadi is a soda lake well studied in terms of its geology and limnology. Research attention has also been drawn to the microbial populations which thrive in this unique habitat but currently there are no reports on the assessment of its microflora using molecular methods. This study aimed to assess the actinobacterial and archaeal communities within Lake Magadi, Kenya a hypersaline –highly alkaline habitat using metagenomic methods as a preliminary study to identify potential candidates for exploitative biology Samples from two sites dubbed Lake Magadi station 2 (LM2) and Lake Magadi salt pan 4 (LMS4) within the Lake Magadi were analyzed using the 16S rRNA gene as a phylogenetic marker. Cluster analysis of taxon-specific 16S rDNA PCR-DGGE profiles revealed moderately heterogeneous actinobacterial and archaeal populations across the sample sites under investigation which is probably a reflection of the differences in abiotic conditions at the study sites. This observation was also confirmed from the multi-dimensional scaling (MDS) plot. PCR-based clonal libraries of actinobacterial and archaeal communities of both study sites retrieved a total of thirty-two clones (twenty actinobacterial and twelve archaeal) were sequenced. Analysis of the sequences revealed cultured and uncultured signatures of microorganisms typical of hypersaline and or highly alkaline niches. A few (3) sequences presented novelty (<96%) in identities with any previously identified organism. It was concluded that the species dominance at site LMS4 [situated within the salt flats of Lake Magadi and site for exploration of trona and its mineralized extensions (nacholite and gayllusite)] is likely to be dictated by anthropogenic stress since most of the microbial signals associated with the study site are typical of saline and or alkaline environmental samples exposed to especially mining but also agricultural and waste management practices. Isolation studies also revealed previously identified strains peculiar to hypersaline brines and sediments. The strains retrieved were affiliated to the taxonomically diverse genus Bacillus and Halomonas sp. The true applications and potential opportunities these isolates have for biotechnology have been well documented. Observations made from the culture dependent and culture independent methods suggests strongly that study site LMS4 is subjected to environmental conditions more severe than at site LM2. This study is a guide for future studies as it provides primary information on the haloalkaliphilic representatives of the actinobacteria phylum and domain Archaea within the soda lake environment. It can serve as a pedestal for investigation into the molecular machinery that supports the haloalkaliphilic lifestyles of inhabiting microorganisms and consequently give leads as to how they can be commercially exploited.

ABSTRACT This thesis investigates through theoretical analysis and imperative research, how Sepedi is represented on SABC, especially on SABC 2 in accordance to the Independent Communications Authority of South Africa (ICASA). Looking back Sepedi programming before democracy and after democracy, SABC has gone through a major transition. This thesis visits the transitions that SABC went through and how SABC is transforming to serve public interests. This essay will composed of empirical observations to depict whether these aims are in fact pursued and achieved.

The purpose of this study is to understand mineral diagenesis authigenic mineral and the effect of climate on mineral of Pleistocene-Holocene sediment deposits in the Southern Kenya Rift. Lake Magadi unique geologic settings are characterized by extreme alkalinity and high silica activities. The mineralogical analysis was achieved by X-Ray diffraction (XRD) and Scanning Electron Microscopy (SEM) applications. The bulk mineralogy (quartz, halite, calcite) is the same on all localities due to similar volcaniclastics compositions throughout the Kenya Rift Valley. The clay mineralogy significantly differ among the groups of sample localities. The differences reflect different tectonic settings and ambient climate regime. In humid climate at higher elevation detrital clay minerals are abundant (feldspars, phillipsite). At lower elevation like Lake Magadi, the clay fractions dominated by authigenic minerals (zeolites and silicate minerals found with zeolites). These results show the potential of clay minerals as terrestrial climate proxies.

This study aimed to explore how gender is constructed, negotiated and enacted in the customary practice of lobolo. Lobolo, sometimes incorrectly referred to as bridewealth or dowry is a practice that centres around the transference of wealth from the groom or a groom’s family to the bride’s family towards the formalisation of marriage. Framed within an African-centred feminist approach I analyse, through narrative discursive analysis, how 27 men and women ages 27 -71, from Johannesburg and Cape Town account for gender and power dynamics in their narratives of participating in lobolo. The African-centred feminist approach I employ critically engages with historical as well as present-day reproductions of patriarchy, capitalism, heteronormativity and other mechanisms of exclusion that are perpetuated through the cultural practice of lobolo. I show how masculinities and femininities are constituted, negotiated and disputed in the narratives of men and women who have participated in lobolo. By employing an African-centered feminist approach I show how gendered dynamics within the practice are shaped by historical and contemporary social, political and economic factors which enable and constrain the exercise of power in various ways. By exploring lobolo through an African-centered feminist narrative approach I demonstrate how the process is more than simply a transference of wealth but rather a complex practice that is used as an apparatus to exercise and expand power in the different stages of the lobolo process. Within this African-centered feminist approach, I argue that lobolo functions to legitimise particular gender positions that can be adopted through marriage; but it can also be used to challenge and contest these roles. The findings of this study suggested that the different stages and process of lobolo reflect a gendered script, which determines the position that men and women are able to adopt, and that this script sets the parameters for the ways in which these roles may be enacted. I find also that the meanings and descriptions of lobolo are embedded within, and reproduce gendered identities but that these identities are not fixed but rather are constantly renegotiated. I conclude that lobolo is not only a custom for formalising marriages but also a tool used by men and women to perform a range of sometimes contradictory functions, including at times establishing and strengthening hegemonic masculinities and femininities but at other times challenging and dismantling these. / Psychology / Ph. D. (Psychology)