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This study focused on how and why secondary school mathematics teachers might situate real-world equity issues in their lessons. Real-world equity issues in the context of mathematics education are real-world issues which might be critically examined in the mathematics lesson and so encourage pupils to be democratic citizens who are critically literate through mathematics. The first phase of the study involved data collection through semi-structured interviews with eight teachers to learn about teachers’ mathematical beliefs. Four of the participants had mathematics degrees and the others had degrees in other disciplines. An adapted version of Ernest’s model of mathematics-related belief systems was used as card sort prompts for the interview. The second phase of the study collected data from observing the participants teach a mathematics lesson in which they situated real-world equity issues. It also gathered data on the participants’ reflections of the lesson. The data formed the basis of eight case studies. In order to identify the different ways in which real-world equity issues can be situated in the mathematics classroom, data from the lesson observations and teachers’ reflections were used to address the question: ‘How might secondary school mathematics teachers situate real-world equity issues in their lessons?’. The data was analysed by identifying the areas of the curriculum addressed in the lesson, and Skovsmose’s Milieus of Learning matrix was used as a framework to analyse the structure of the lesson. Data from interviews and teachers’ reflections were used to address the question: ‘Why might secondary school mathematics teachers situate real-world equity issues in their lessons?’. Ernest’s model of mathematics-related belief systems was used to analyse the interview data and identify what motivated teachers to situate real-world equity issues in their lessons in the way they did. As the cohort comprised of mathematics teachers with mathematics degrees and degrees from other disciplines, the study also analysed the data between participants to determine if there is a difference between teachers from diverse academic backgrounds in terms of their mathematical beliefs and practices. By drawing on the analysis, the study arrived at conclusions to provide potential ways in which teachers from diverse beliefs and academic backgrounds might be able to situate real-world equity issues in the mathematics classroom.

Candida albicans is an opportunistic polymorphic fungus that causes clinically important disease candidiasis to humans. Being polymorphic C. albicans can grow in yeast, hyphae, or pseudohyphae forms and the switch from one form to another is required for virulence. The morphological transitions from one phase to another are carefully orchestrated events which are regulated by several signal transduction pathways. Several environmental factors determine the morphology of the fungus C. albicans. For example growth at lower temperature ~30 ºC, in preferred nitrogen sources cause the fungus to grow as yeasts while at higher temperature ~37 ºC and in poor nitrogen sources, in the presence of serum, N-acetyl glucosamine, or high CO2, C. albicans cells grow as hyphae. Under several clinically relevant circumstances, including biofilms, C. albicans cells encounter poor or low nitrogen conditions. In this project utilization of different nitrogen sources by C. albicans was evaluated and their roles in pathogenesis were studied. The aromatic amino acids are metabolized when the C. albicans cells grow under poor nitrogen conditions, and the resulting carbon skeletons are secreted outside the cell. They are well known as fusel oils or aromatic alcohols. The aromatic alcohol biosynthesis is enhanced under anaerobic conditions compared to aerobic conditions, by the presence of precursor amino acids (phenylalanine, tyrosine, or tryptophan), and in alkaline conditions compared to acidic conditions, but it is reduced greatly in the presence of ammonia. Also, aromatic alcohol yield is dependent on the transcription regulators Aro80p and Rim101p. In another project the role of arginine metabolism in the yeast to hypha morphological switch was studied. When C. albicans cells enter the bloodstream, they first encounter macrophages and are engulfed by them. But in four to six hours C. albicans cells form hyphae, penetrate and kill the macrophages, and get out in the bloodstream again. In this series of events at the initial phase, right after engulfment, C. albicans up-regulates arginine biosynthesis. We found that arginine biosynthesis is critical for the fungus because it is metabolized and produces CO2 inside the cell, a signal important for the yeast to hypha switch. C. albicans mutants that either failed to make arginine (arginine auxotrophs) or could not metabolize arginine to CO2 (urea amidolyase mutants) were defective in making germ tubes inside the macrophages. However, wild type C. albicans and C. albicans auxotrophic for other amino acids than arginine can kill macrophages within four to six hours after phagocytosis. So, another project studied if macrophages can induce appropriate cytokines within that short time span before being killed by C. albicans. We found that after engulfing C. albicans, macrophages induce cytokines within one hour. Chief among them were IL-6, IL-23, and TGF-β, important for the development of the Th-17 subset of T cells. Finally, two major components of C. albicans, the quorum sensing molecule farnesol and the cell wall component zymosan, together induced TLR2, a pattern recognition receptor, and both were responsible for the induction of IL-6, IL-23, and TGF-β. Farnesol was ca. 100 times more effective than farnesoic acid at inducing these cytokines. Overall, this body of work has taken a major step towards elucidating farnesol‟s mode of action as a virulence factor and a lipid signaling molecule while at the same time highlighting the magnitude of the gaps remaining our knowledge.