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The application of N-heterocyclic carbenes (NHCs) in organic and organometallic chemistry has been well-established. The utilization of Zr(NMe2)4 for transmetallation has facilitated the synthesis of CCC-NHC pincer transition metal complexes since 2005 by our group, including Fe, Co, Rh, Ir, Ni, and Pt. However, there have been no reports on the synthesis, characterization, and application of CCC-NHC pincer complexes involving Re and Mn to date. This dissertation aims to address this gap by discussing the synthesis and catalytic activities of CCC-NHC pincer Re and Mn complexes in crossed-coupling reactions. Chapter II will focus on the synthesis of the CCC-NHC pincer Re complex. The synthesis involved transmetallation with CCC-NHC pincer Zr complex using Re(CO)5Cl. The Re complex was characterized by 1H and 13C NMR spectroscopy, mass spectroscopy and its structure was determined by X-ray crystallographic methods. Catalytic activities of Re complex were demonstrated through borrowing hydrogen reactions for the crossed-coupling between ketones and primary alcohols, yielding α-alkylated ketones with water as the only by-product. The borrowing hydrogen reaction improved the economic efficiency when it did not require the good leaving group that conversed from primary alcohols. A wide range of substrates yielded yields ranging from 53% to 92%. Chapter III willdiscuss the expanded application of the Re complex, including borrowing hydrogen reactions for coupling between primary and secondary alcohols, as well as one-pot synthesis of quinolines via dehydrogenative/oxidative cyclization reactions. Control experiments support the proposed catalytic cycle of borrowing hydrogen reactions by the Re complex. In Chapter IV, the synthesis and catalytic activities of CCC-NHC pincer Mn complex are examined. The proposed structure of the Mn complex was supported by NMR spectroscopy, mass spectroscopy, and single X-ray diffraction. The Mn complex demonstrates catalytic activities through borrowing hydrogen and dehydrogenative cyclization, yielding α-alkylated ketones, 2-oxindole derivatives, and quinolines. The control experiments were set up and the proposed mechanism of Mn complex for borrowing hydrogen reaction were consistent with Re complex.

Les polyamines sont des intermédiaires industriels très importants, cependant leur production dépend du pétrole, d’un apport en hydrogène et de produits toxiques (HCN, HCl). Il est donc important de changer de matière première. Dans cette optique, nous visons ici à aminer des alcools biosourcés. Nous avons donc réalisé des calculs DFT afin de comprendre les étapes clés de l’amination d’alcools, pour en maitriser les principes et résultats.En particulier, nous avons montré que l’environnement chimique jouait un grand rôle pendant cette réaction : expérimentalement, le Nickel (Ni) est plus actif que le Palladium (Pd). Cependant, les modèles de surfaces nues les prédisent aussi actifs. En prenant en compte un recouvrement de 1/9 monocouche en ammoniaque sur les surfaces, nous avons prédit une réactivité correcte : Ni plus actif que Pd.Nous avons aussi étudié les effets de l’environnement chimique sur l’hydrogénation de l’acide levulinique par l’acide formique, et sur l’isomérisation de l’isosorbide. Nous avons montré qu’il jouait un rôle sur la stabilité d’intermédiaires, modifiant l’activité des catalyseurs. / Polyamines are important industrial intermediates. Their production however relies on petroleum, external hydrogen input and toxic products (HCN, HCl). It becomes therefore important to change the feedstock. In that optic, we aim here at aminate biosourced alcohols.We have performed a DFT study in order to understand alcohols amination key steps, to master its principle and outcomes.In particular, we showed that the chemical environment was playing an important role during that reaction : experimentally, Nickel (Ni) is more active than Palladium (Pd). However bare surfaces models were not predicting that fact. Taking a 1/9-monolayer ammonia coverage into account allowed to retrieve the correct reactivity.We studied the effects of the chemical environment on levulinic acid hydrogenation by formic acid, and on isosorbide isomerization. We showed that it was playing a key role on intermediates stability, modifying the catalysts activity.

This qual-quan case study investigated the role of code-switching (CS) in education in four senior secondary schools in Botswana. CS is a communicative strategy used in many places, including Botswana, during formal and informal social occasions. CS also occurs in education; however, its occurrence is viewed as a somewhat problematical phenomenon – that it signals the speaker’s lack of proficiency in the Language of Learning and Teaching (LoLT). The study also investigated if CS in the classroom contravenes the country’s Language-in-Education Policy (LiEP), which states that English is the medium of instruction throughout the education system (Botswana Government White Paper No.2 of 1994). The study found that CS occurrence in teaching and learning has positive and negative educational effects. However, its use has adverse implications for the LiEP of Botswana. Consequently, recommendations are made on the effective use of CS and on the revision of the LiEP. The study is divided into nine chapters. Chapter One is the introduction and covers: Botswana’s language situation, including the status of English generally and in education in particular, the statement and analysis of the problem, research questions and the importance of the study. Chapter Two gives a comprehensive review of the literature on CS generally and CS in education in particular. The key words are: code-switching, code-mixing, borrowing, nonce-borrowing and re-borrowing / double-plural. Botswana’s LiEP is also discussed with respect to language planning, education and educational development. Chapter Three discusses the research design and the data-collection methods. These include: the research sites, sample selection and sampling procedures, data-collection instruments and their administration, and the independent and dependent variables used in data-collection. The importance of pre-testing the research instruments, ethical aspects observed and problems encountered during the data-collection stage are also highlighted. The role of the University of Pretoria’s Statistics Department is also explained. Hymes’ mnemonic of SPEAKING used in the analysis of the qualitative data is also described. Chapter Four presents the quantitative analysis of the respondents’ demographic details, and highlighting the differences and similarities identified. Chapters Five and Six present the results from the quantitative analysis of the teachers’ and learners’ data. The former presents the teachers’ evaluation of the learners’ language proficiency in class; the latter presents the learners’ subjective self-evaluation of their own English proficiency and their evaluation of teachers’ proficiency in English. Furthermore, both chapters respectively present the teachers and learners’ views on the role of English, Setswana and other indigenous languages in education as LoLT, and their attitude towards CS in education. The significance or the non-significance of the analyzed results is also presented. Chapter Seven presents the results from the qualitative analysis of the data (through the application of Hymes’ mnemonic of SPEAKING) obtained through lesson observations. Chapter Eight deals with the interpretation and discussion of the results through answering the main research questions. Chapter Nine presents the study’s summary, conclusions and recommendations on CS in the classroom and on Botswana’s LiEP. The study’s limitations and implications for further research are also discussed. / Thesis (DPhil)--University of Pretoria, 2011. / Afrikaans / unrestricted

Данная работа посвящена особенностям адаптации англоязычных заимствований общественно-политического дискурса в русском и испанском языках. Теоретическая часть исследования включает в себя определение терминологической базы и особенностей перевода общественно-политических текстов; выявление функций англоязычных заимствований в общественно-политическом дискурсе и формулировку основных способов адаптации англоязычных заимствований общественно-политического дискурса к нормам принимающего языка. В методологической части исследования представлен анализ существующих публикаций и научно-исследовательских работ, посвященных англоязычным заимствованиям, а также определены методы и методологические принципы настоящего исследования. Практическая часть посвящена отбору и интерпретации материала исследования, анализу способов и моделей адаптации англоязычных заимствований общественно-политического дискурса в русском и испанском языках на сформированном материале исследования, а также сравнительному анализу выявленных способов и моделей. В Заключении представлены основные выводы данной исследовательской работы. Результаты исследования могут быть использованы для анализа англоязычных заимствований в других языках-реципиентах и для анализа заимствований из других языков, а также для адаптации новой лексики, заимствованной из английского языка, к нормам русского и испанского языков. / This study is dedicated to English-language borrowings of socio-political discourse in Russian and Spanish and features of their adaptation to the receiving languages. The theoretical part of the study includes the definition of the study terminology and the description of the translation of socio-political texts and its main features; the identification of the functions of English-language borrowings in socio-political discourse and the elaboration on the main ways of English-language borrowing adaptation to the norms of the receiving languages. The methodological part of the study represents an analysis of the existing scientific publications and research papers on English-language borrowings, as well as the methods and methodological principles of the current study. The practical part is devoted to the selection and interpretation of the study material, the analysis of methods and models of English-language borrowing adaptation to the norms of Russian and Spanish languages based on the study material, as well as a comparative analysis of the identified methods and models of English-language borrowing adaptation. The main takeaways of this study are presented in the conclusion. The results of this study can be used to analyze English-language borrowings in other recipient languages and to analyze borrowings from other languages, as well as to adapt new vocabulary borrowed from English to the norms of Russian and Spanish languages.

The work selected for this portfolio comprises two language-specific case studies (‘Russian and Soviet loanwords and calques in the Czech lexicon since the beginning of the twentieth century’ and ‘Češi a slovenština’ [The Czechs and the Slovak language]), two publications on the critical reception of foreign vocabulary in Czech (‘The legacy and limitations of Czech purism’ and Attitudes to lexical borrowing in the Czech Republic), and a detailed article on the implications of naming practices for perceptions of the self and others (‘The Czech-speaking lands, their peoples and contact communities: titles, names and ethnonyms’). Extensive use is made of original material, including two nationwide quantitative surveys conducted on my behalf by the Public Opinion Research Centre of the Institute of Sociology of the Academy of Sciences of the Czech Republic (CVVM), and two small-scale questionnaires carried out for me by Dr Miroslav Růžička of the Czech University of Life Sciences (Prague), as well as a range of other empirical data, dictionaries, encyclopaedias, electronic corpora, and additional sources of lexical and historical information. My commentary employs a thematic approach, which aims both to acquaint the reader with the main findings of each of my publications, and to indicate the broad direction of my output. Supplementary information is provided in the commentary, where required, to contextualize and synthesize my arguments, to shed light on recent scholarship in cognate fields, and to ensure narrative continuity. The ‘new’ knowledge thus complements and frames the discussion of my selected publications, thereby helping to guide the reader through the exposition of my writings. The principal unifying themes of the chosen pieces are their emphasis on (1) the role of language in the national consciousness and self-perception, (2) the influence of external forces on the shaping of the Czech lexicon, and people’s reactions to those forces, (3) public perceptions of lexical borrowing, and (4) changing attitudes to the notion of ‘foreign’, as reflected in the national idiom. The commentary is divided into eight chapters, as listed in the Table of Contents. My study begins with a general introduction to my academic background, and to the content and themes of this thesis, as summarized above. Chapter 2 is based principally on my article ‘The legacy and limitations of Czech purism’, and provides a combination of historical setting and statistical analysis. The next chapter presents a résumé of the overall impact of foreign languages and cultures on the historical development of Czech, with the aim of contextualizing the findings of subsequent chapters. Chapter 4, which draws mainly on ‘Russian and Soviet loanwords and calques in the Czech lexicon since the beginning of the twentieth century’, reevaluates the impact of Russian and ‘Soviet speak’ on the Czech lexicon. In chapter 5, I consider in detail the asymmetrical nature of Czech–Slovak language relations, with reference to the views of over 1,400 informants interviewed for ‘Češi a slovenština’ and Attitudes to lexical borrowing in the Czech Republic. Chapter 6 compares the results of my survey for the latter publication, referred to as ‘Perceptions’, with a series of other questionnaires, including Tejnor’s groundbreaking 1970 study of foreign words. ‘The Czech-speaking lands, their peoples and contact communities: titles, names and ethnonyms’ provides the substance of much of chapter 7, which focuses on the Czechs’ tendency to see themselves in terms of opposition to outsiders, and on the depiction of ‘foreignness’ in the Czech lexicon. The commentary concludes with a summary of my principal observations relating to aspects of language contact and lexical borrowing in Czech, and to their implications for the self and others. Taken collectively, the eight chapters provide a framework for the discussion of my published work and for the thematic and conceptual links that validate their consideration as a corpus of cognate research activity.

We present in this thesis three distinct models in Financial Economics. In the first chapter we present a pure exchange economy model with collateral constraints in the spirit of Kiyotaki and Moore (1997). As a first result in this chapter we prove the existence of an equilibrium for this type of economies. We show that in this type of models bubbles can exist and provide a bubble example in which the asset containing the bubble pays positive dividends. We also show for the case of high interest rates the equivalence between this type of models and the Arrow-Debreu market structure. In the second chapter we present a model with limited commitment and one-side exclusion from financial markets in case of default. For this type of models we prove a no-trade theorem in the spirit of Bulow and Rogoff (1989). This is done for an economy with and without bounded investment in a productive activity. The third chapter presents a 2 period economy with complete markets, and 250 states of the world and assets. For this economies we generate a sequence of observed returns, and we show that a market proxy containing only 80% of the assets in the economy provides similar results as the true market portfolio when estimating the CAPM. We also show that for the examples we present a vast amount of observations is required in order to reject the CAPM. This raises the question what the driving force behind the bad empirical performance of the CAPM is.

Due to widespread decentralization of spending responsibilities, increasing revenue power and borrowing capacity of sub-national governments, sub-national borrowing has become an increasingly important source of sub-national finance. While there are arguments for and against giving sub-national authorities room for raising their own financial resources, appropriate sub-national borrowing regulatory framework can reduce chances of defaults and fiscal crises. This dissertation investigates the effectiveness of sub-national borrowing regulations in maintaining fiscal sustainability. More precisely, it tests the hypothesis that is sub-national borrowing is restricted to financing capital investments (the “golden rule”), and if the sub-national governments are provided with some measure of revenue autonomy, then the sub-national borrowing should not endanger fiscal sustainability. Based on the sub-national government panel data for 57 countries between 1990 and 2008 and applying the system GMM estimator and the survival analysis, this dissertation provides support for this hypothesis. The results suggest that the “golden rule” is effective in maintaining fiscal sustainability at both general and sub-national government level. Sub-national tax autonomy, however, seems to have positive but very small marginal effect on fiscal sustainability. The obtained results also emphasize the risk of the soft budget constraint and the moral hazard. Significant central government financing may give encouraging signs to the sub-national governments to over-borrow and to expect being bailed out by the central government. The results obtained in this dissertation imply following policy recommendations. First, sub-national government borrowing does not have to endanger fiscal sustainability if the borrowing regulation framework is well designed and according to specific country circumstances. Second, reducing fiscal dependence on central government financing reduces the risk of moral hazard and improves the effectiveness of borrowing control in maintaining fiscal balance at the sustainable level.

The Social Security System is projected to encounter both short-term and long-term financial crises. The economic effectiveness and impacts of alternative solutions to both problems are analyzed. Government projections show the short-term deficit can be solved through interfund borrowing. Solving the long-term deficit will require the generation of new funds. All four solutions analyzed will increase unemployment, inflation, and interest rates, and decrease growth potential. A combination of increased OASI taxation and mandatory coverage is recommended as the most effective solution with the least adverse economic consequences.