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I) Synthesis of Spiroindenes by Enolate-Directed Ruthenium-Catalyzed Oxidative Annulation of Alkynes with 2-Aryl-1,3-dicarbonyl Compounds The synthesis of carbocycles by the ruthenium-catalyzed oxidative annulation of alkynes with 2-aryl cyclic 1,3-dicarbonyl substrates is described. Proceeding by the functionalization of C(sp3)–H and C(sp2)–H bonds, and the formation of all-carbon quaternary centers, the reactions provide a diverse range of spiroindenes in good yields and high levels of regioselectivity. II) Synthesis of Benzopyrans by Pd(II)- or Ru(II)-Catalyzed C–H Alkenylation of 2-Aryl-3-hydroxy-2-cyclohexenones We have explored the 2-aryl-3-hydroxy-2-cyclohexenones as competent substrates for palladium- and ruthenium-catalyzed C–H alkenylation reactions with terminal alkenes. This process affords benzopyrans, in most cases, with good functional group tolerance. III) Synthesis of Spiroindanes by Palladium-Catalyzed Oxidative Annulations of 1,3-Dienes Involving C–H Functionalization 1,3-Dienes have been an underexplored class of substrates in catalytic oxidative annulation reactions involving C‒H functionalization. The synthesis of spiroindanes by the palladium-catalyzed oxidative annulation of 1,3-dienes with 2-aryl cyclic 1,3-dicarbonyl compounds is described. Several examples of the dearomatizing oxidative annulation of 1,3-dienes with 1-aryl-2-naphthols are also presented. IV) Enantioselective Spiroindene Formation via C‒H Functionalization Using Chiral Cyclopentadienyl Rhodium Catalysts A chiral cyclopentadienyl rhodium ligand with an atropchiral biaryl backbone enables an asymmetric synthesis of spiroindenes from 2-aryl-1,3-dicarbonyl compounds and alkynes. The process affords a range of products with all-carbon quaternary center in high yields and excellent enantiselectivities. The good functional group tolerance and broad substrate generality are the advantages of this reaction.

This thesis discusses the adaptation and convergence in corporate governance to international norms in Pakistan. Pakistan is an underdeveloped but an emerging market with inefficient legal, regulatory, judicial, institutional and governance norms. In recent times there have been some reforms in the corporate sector of Pakistan but lack of infrastructure and a dearth of research were barriers to reform generally. Therefore, this thesis seeks to identify corporate governance issues in Pakistan, and discusses analytically the possibility and effectiveness of convergence in corporate governance to international norms in Pakistan. To this end, it focuses on three aspects of convergence in corporate governance in Pakistan. First, it discusses the prospects and application of convergence in corporate governance in Pakistan. Second, it analyses critically, from a comparative perspective, three core corporate governance issues in Pakistan. The corporate sector in Pakistan is highly concentrated with an underdeveloped capital market and inefficient enforcement mechanisms. The conflict between shareholders and management, and shareholders inter se are major issues of corporate governance in Pakistan. The former conflict is addressed by reducing agency cost and the latter by ensuring minority protection. These conflicts are analysed comprehensively through comparative studies. Furthermore, the market and judiciary in Pakistan have failed to provide investors with protection. This thesis discusses the reform process in the market and judiciary in order to improve enforcement mechanisms. In addition, it discusses the possibility of convergence and effectiveness of adaptation in these issues. Third, as Pakistan is an ideological country whose constitution prescribes Islam as the state religion which, in turn, prescribes Islamic injunctions as basic norms, convergence to any foreign corporate governance feature will have to pass the litmus test of Islamic norms. Therefore, the thesis also identifies the possibility of filtration of foreign governance features through Islamic norms. The thesis concludes that the corporate sector in Pakistan is underdeveloped with weak investor rights and enforcement mechanisms. There is, therefore, a need to enhance investor protection in order to improve corporate governance which, in turn, will improve the economy of the country. In addition, the conclusion is reached that in convergence to Western corporate governance features in Pakistan, Islamic norms may act as a litmus test which may not be as problematic as it appears at first sight.

Managing Surface Ambiguity in the Generation of Referring Expressions (Imtiaz Hussain Khan) Most algorithms for the Generation of Referring Expressions tend to generate distinguishing descriptions at the semantic level, disregarding the ways in which surface issues can affect their quality. This thesis explores the role of surface ambiguities in referring expressions and how the risk of such ambiguities should be taken into account by an algorithm that generates referring expressions. This was done by focussing on the type of surface ambiguity which arises when adjectives occur in coordinated structures (as in the old men and women). The central idea is to use statistical information about lexical co-occurrence to estimate which interpretation of a phrase is most likely for human readers, and to avoid generating phrases where misunderstandings are likely. We develop specific hypotheses, and test them by running experiments with human participants. We found that the Word Sketches are a reliable source of information to predict the likelihood of a reading. The avoidance of misunderstandings is not the only issue to be dealt with in this thesis. Since the avoidance of misunderstandings might be achieved at the cost of very lengthy (or perhaps very disfluent) expressions, it is important to select an optimal expression (i.e., the expression which is preferred by most readers) from various alternatives available. Again, we develop specific hypotheses, and recorded human preferences in a forced-choice manner. We found that participants preferred clear (i.e., not likely to be misunderstood) expressions to unclear ones, but if several of the expressions were clear then brief expressions were preferred over their longer counterparts. The results of these empirical studies motivated the design of a GRE algorithm. The implemented algorithm builds a plural distinguishing description for the intended referents (if one exists), using words; applies transformation rules to the distinguishing description to construct a set of distinguishing descriptions that are logically equivalent. Each description in the set is realised as a corresponding English noun phrase (NP) using appropriate realisation rules; the most likely reading of each NP is determined. One NP is selected for output. A further experiment verifies that the kinds of expressions produced by the algorithm are optimal for readers: they are understood accurately and quickly by readers.

The cell cycle, with its highly conserved features, is a fundamental driver for the temporal control of cell growth and proliferation in tissues - while abnormal control and modulation of the cell cycle are characteristic of cancer cells, particularly in response to therapy. A central theme in cancer biology is to resolve and understand the origin and nature of innate and induced heterogeneity at the cell population level. Cellular heterogeneity - comprising structural, temporal and functional dimensions - is a confounding factor in the analysis of cell population dynamics and has implications at physiological, pathological and therapeutic levels. There is an exceptional advancement in the applications of imaging and cell tracking technologies dedicated to the area of cytometric research, that demand an integrated bioinformatics environment for high-content data extraction and interrogation. Image-derived cell-based analyses, where time is the quality parameter also demand unique solutions with the aim of enabling image encoding of spatiotemporal cellular events within complex cell populations. The perspective for this thesis is the complex yet poorly understood nature of cancer and the opportunities offered by rapidly evolving cytometric technologies. The research addresses the intellectual aspects of a bioinformatics framework for cellular informatics that encompass integrated data encoding, archiving, mining and analysis tools and methods capable of producing in silico cellular fingerprints for the responses of cell populations to perturbing influences. The overall goal is to understand the effects of anti-cancer drugs in complex and potentially heterogeneous neoplastic cellular systems by providing hypothesis testing opportunities. Cell lineage maps encoded from timelapse microscopy image sequences sit at the core of the proposed bioinformatics infrastructure developed in the current work. Through a number of data mining, analysis and visualisation tools the interactions and relationships within and between lineages have provided dynamic patterns for the modulation of the cell cycle in disease and under stress. The lineage data, accessible through databases implemented during the current study, has provided a rich repository for pharmacodynamic (PD) modelling and validation and has thus laid the foundation for fabricating a comprehensive knowledge base for linking both cellular and molecular behaviour patterns. These provide the foundation for meeting the aspirations of systems biology and drug discovery.