MSc, School of Chemistry, Faculty of Science, University of the Witwatersrand, 2011 / In this work, a detailed study of the evaluation of gold-based catalysts supported on manganese oxides for the oxidation of volatile organic compounds (VOCs) has been undertaken. Model catalysts were prepared by deposition-precipitation methods to establish the effect of the support on the catalytic activity of the gold catalysts. The catalysts were characterised by X-ray diffraction, transmission electron microscopy, N2–physisorption measurements and temperature programmed reduction techniques. The activity of the catalysts for VOC oxidation reactions were tested in a continuous flow fix bed glass reactor. The products were analysed by GC/TCD and GC/FID. The catalysts Au/TiO2, Au/Al2O3, Au/ZnO and Au/MnO2 were used for the VOC oxidation reaction. 2-propanol, 2-butanol and toluene were used as VOCs for the study. These were chosen because they are important indoor pollutants given their wide laboratory use and high volatility. Toluene was found to be the most difficult to oxidise, followed by 2-propanol. The effect of calcination temperature and preparation procedure was evaluated for the gold/manganese oxide catalysts. Au/b-MnO2 catalysts prepared by deposition-precipitation showed some catalytic performance which was less than the performance shown by Au/MnOx, prepared by co-precipitation. g-MnO2 proved to be more efficient in the oxidation of 2-propanol than pyrosulite phase MnO2. The addition of gold to any metal oxide support was found to enhance the oxidation of VOCs. Gold-based catalysts were more active than the Ce/MnO2 catalyst. Catalytic tests showed that Au/CeO2 was the superior catalyst for the total oxidation of toluene, 2-propanol and 2-butanol. Ceria is a highly reducible oxide and the formation of gold–ceria interactions produced an even more easily reduced material. University of the Witwatersrand, Johannesburg ii

This study is a qualitative enquiry into the experiences of grade 12 Business Studies educators in the process of compiling school-based assessment portfolios for learners in 2009. It answers the question: “What are the primary challenges in the process of compiling School Based Assessment (SBA) portfolios for FET Business Studies? The literature review covers the strengths and limitations of portfolio-based assessment as a strategy for combining formative and summative assessment purposes, the complexities of curriculum change and implementation, and bureaucratic and professional forms of accountability. In order to understand what is involved in the portfolio assessment implementation processes, I analyzed six assessment policy documents, two circulars and two Chief Moderators’ reports. I also interviewed four teachers and four principals, two each from more and less advantaged schools in Johannesburg. Findings from the document analysis illustrate the incomplete and at times contradictory nature of the assessment policies and circulars, while the interviews highlighted a lack of communication and mutual adaption between stake holders in the compilation of SBA portfolios. The key recommendation is that the concept of mutual adaptation may be useful to overcoming the challenges encountered in SBA portfolio compilation.

Thesis (M.Com. (Development Theory and Policy))--University of the Witwatersrand, Faculty of Commerce, Law and Management, School of Economic and Business Sciences, 2014. / Mozambique is currently moving from an aid dependent country to mineral dependent given the mining boom happening there thanks to the discoveries of huge reserves of coal, mineral sands and natural gas. The country is set to become one of the world's twenty top producers of natural gas and top ten largest producers of coal. This research is a case study focusing on coal-based linkages that can foster broad economic growth and development in Mozambique. Using a political economy perspective, the research investigates the question about how the country can optimise the mining boom through coalbased economic linkages to foster broader socio-economic development. The research finds that under the combination of its current fiscal and mineral regime with infrastructure problems plus the inexistence of a coal-based linkage policy, Mozambique will get negligible benefit from the exploitation of its finite coal resources. A major overhaul of these regimes is needed for it to make use of its coal to catalyse wider growth and development, before it is left with little other than large holes in the ground.

Information literacy (IL) is recognized as the overall critical literacy for the 21st Century. Although large amounts of digital information are available, there is concern within higher education that students lack the competencies to assess and analyse sources in terms of relevance to their courses. Information literacy skills are of critical importance in teaching medical students to engage with evidence-based medicine (EBM), often within a problem-based learning (PBL) curriculum. Information practices that underpin academic and professional life should be embedded into the learning experience of the subject, and not taught extraneously in isolated silos. Attitudes of teaching staff at the Faculty of Health Sciences, University of the Witwatersrand towards embedding evidence-based information literacy skills into the Graduate Entry Medical Programme 1 and 2 curriculum were examined. Existing integration of IL skills into the curriculum was shown to be limited, and not as high as perceived by educators. Five barriers against the integration of IL skills, and six opportunities for embedding information literacy, were identified in the curriculum. Awareness of evidence-based practice was found to be high, and collaborative teaching of IL skills with librarians was accepted by a large majority of educators. Dynamic Purposeful Learning (DPL) was proposed as a constructivist framework into which collaborative teaching of IL skills could be placed. DPL draws on active and collaborative learning, as well as cognitive scaffolding and apprenticeship, and is suited to PBL in the context of medical education.

This thesis explores the role of youth workers who utilize the arts in Soacha, Colombia. Through a historical and anthropological lens the findings reveal the objectives of the workers and the impact the work has as an intervention with the children. Through the case study of nine youth workers and two administrators of the local NGO, La Fundación Proyecto de Vida, I show how a comprehensive approach strengthens youth's social and personal capacities. This Colombian model of intervention includes workshops that cover areas such as music, visual arts, movement, physical health, and the environment. In addition to the workshops the organization provides psychological resources through family counseling, art and psychodynamic therapy, along with onsite cafeteria service. Ultimately I illustrate how this comprehensive, arts-based approach to support the youth can break the cycle of violence that is otherwise perpetuated by the lack of governmental social programs.

Thesis advisor: Amir H. Hoveyda / Chapter 1. Exploring Ligand Effects in Ruthenium Dithiolate Carbene Complexes. Ruthenium dithiolate metathesis catalysts discovered in the Hoveyda group have been a valuable addition to the field of olefin metathesis. While the catalyst shows unique selectivity and reactivity, quantifying and mapping key interactions in the catalyst framework to elucidate and explain causes is difficult. We, therefore, decided to use the neutral chelating or monodentate ligand, controlling initiation, as a structural probe. By altering its properties and observing changes in the catalyst, we sought to deepen our understanding of these complexes. We established a trans influence series with over 20 catalysts and correlated the impact on catalyst initiation. Further, we show that in the case of strongly σ-donating and π-accepting ligands such as phosphites and isonitriles, the complex exhibits fluxional behavior. The catalysts ground state is elevated to such a degree that thiolate Ruthenium bonds become labile and rapidly exchange. While Ruthenium dithiolate catalysts were readily applied to metathesis polymerization, their use in the synthesis of small molecules was initially less forthcoming. Specifically, reactions involving terminal olefins lead to rapid catalyst deactivation and only low conversion. We were able to determine that the potential energy stored in the trans-influence between the thiolate ligand and the NHC can be released in a sulfur shift to reactive Ruthenium methylidene species. Since methylidenes are formed by reaction with terminal olefins, use of an excess of internal olefins can prevent their formation. Chapter 2. Harnessing Catalyst Fluxionality in Olefin Metathesis. Depending on its use, material requirements can vary significantly. Materials that can easily be adapted to a given application, for example by varying tensile strength, melting point or solubility, are desirable. Controlling the polymers tacticity (the adjacent stereocenters in a polymer chain) is a straight forward way to achieve just that. Ru dithiolate catalysts should give highly syndiotactic polymers due to their single stereocenter undergoing inversion during every metathesis step. The fluxional nature of the catalyst allows for control of polymer tacticity from 50% (atactic) to ≥95% syndiotacticity by changing monomer concentration. We determined the factors which are responsible for fluxionality and synthesized complexes that give either high or low levels of tacticity over a broader range of monomer concentration. Chapter 3. Harnessing Catalyst Fluxionality in Olefin Metathesis. The importance of fluorine-containing molecules is hard to understate, keeping in mind the surge of new methodologies for their synthesis and the medical breakthroughs they enable. However, efficient and practical syntheses of stereodefined alkenyl fluorides are rare. In this context, we have developed enantioselective boryl allylic substitution of allylic fluorides, which yield enantioenriched γ-alkenyl fluoride substituted allyl boronate esters. The reaction is catalyzed by Cu-based catalysts that are prepared in-situ and delivered as products with high yield and enantioselectivity. Mechanistic inquiry shows the reaction is not a concerted allylic substitution. An intermediate Cu alkyl complex is formed after the Cu boron addition is made to the double bond, which only slowly undergoes β-fluorine elimination in the presence of a Lewis acid. / Thesis (PhD) — Boston College, 2019. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Real-time embedded systems can be found in a large number of devices we use, including safety-critical systems. Useful for their small size and low power consumption, they are also harder to protect against state-of-the-art attacks than general purpose systems due to their lack of hardware features. Even current defenses may not be applicable since instrumentation added to defend real-time embedded systems may cause them to miss their deadlines, rending them inoperable. We show that the static properties obtained by the scheduling policies can be used as security guarantees for the tasks composing the program. By completely securing a subset of the tasks of the program only using the scheduler policy, we remove the need to add external instrumentation on these tasks, reducing the amount of extra instructions needed to entirely protect the system. With less instrumentation, the overhead added by the defenses is reduced and can therefore be applied to a larger number of systems.

Sometimes it feels as though everybody has an opinion on how you should bring up your child – and no two people seem to agree on how it should be done for the best! Parenting with Reason cuts through the masses of confusing and often contradictory advice about parenting by providing hard evidence to back up the tough decisions all parents face. Unlike many self-help guides to parenting which are based on the opinion of one author, this book is based on many findings from scientific research, giving you a trustworthy, ‘evidence-based’ guide to help see your way through parenting dilemmas. Written by a clinical psychologist, a developmental psychologist and a doctor of family medicine, the book looks at pressing questions such as: 'What should I do when my child acts up?', 'How can I get my baby to sleep through the night?' and 'How do I begin to toilet-train my child?' The authors, who are also parents themselves, debunk common myths about parenting, such as the notion that a healthy baby needs to be able to breastfeed at will throughout the night, or the idea that children who are adopted need specialized counselling. They also cover issues such as how children might be affected by seeing violence on television, how a parent’s psychological health can affect their child, what the scientific evidence is for and against circumcision, and how divorce and adoption affect a child’s development. The end of each chapter gives you 'The Bottom Line', a handy summary of the key points of each issue. This book is ideal for new or prospective parents, and paediatricians, family health providers and anyone who works with children and their parents will also find the book’s objective, scientific approach useful in their work. / https://dc.etsu.edu/etsu_books/1208/thumbnail.jpg

College requires students to read strategically in order to be academically successful (Caverly, Nicholson, & Radcliffe, 2004). Strategic readers utilize a variety of strategies, including metacognitive reading strategies (Mokhtari & Reichard, 2002; Pressley & Afflerbach, 1995). However, not all students use the same strategies when reading academic text. The purpose of this study was to explore whether students enrolled in a developmental reading course report using different metacognitive reading strategies than students who are enrolled in a college-level English course. The Metacognitive Awareness of Reading Strategies Inventory (Mokhatari & Reichard, 2002) was administered to 423 students at a community college in the southeastern United States. The results of the Tests of Between-Subjects Effects indicated that the main effect for group membership was not significant. The results of the Tests of Within-Subjects Effects indicated that problem solving was reportedly used relatively equally by the two groups, but global and support reading strategies were used less by the English group,with the interaction effect even stronger for support strategies. The implications of this study on teaching and further research were also explored. / by Sophia Munro. / Thesis (Ph.D.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.

Despite growing interest in sustainable operations and supply management (SOSM) from both academics and practitioners, literature examining the area remains fragmented. This thesis presents the findings of a study investigating the influence of exogenous pressures and endogenous capability-building, independently and interactively, on sustainable operations and supply management practice adoption. Exogenous pressures, such as regulation and consumer demands, may influence the decision to adopt specific SOSM practices. For example, within the fashion industry, media exposés have heightened consumer awareness of unethical practices creating pressure for fashion retailers to address these concerns within their supply chains more fully. Endogenous pressures, in this case relating to capability-building, may also influence the SOSM practices that organisations choose to adopt, such as the implementation of recycling strategies or energy efficiency initiatives which can reduce both the cost and environmental impact of the focal organisation.