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Many techniques have been developed in computer vision to recover three-dimensional shape from two-dimensional images. These techniques impose various combinations of assumptions/restrictions of conditions to produce a representation of shape (e.g. surface normals or a height map). Although great progress has been made it is a problem which remains far from solved. In this thesis we propose a new approach to shape recovery - namely `mutual illumination photometric stereo'. We exploit the presence of colourful mutual illumination in an environment to recover the shape of objects from a single image.

The polyphenolic pigments of black tea include the theaflavins (TF), the flavonol glycosides (FG) and a group of uncharacterised brown pigments referred to as thearubigins (TR). The TR are shown to be a complex, heterogeneous group of compounds, the majority of which are unresolvable by reverse phase HPLC. Fractionation procedures have been modified, developed, combined and applied to black tea liquor, to improve the separation of black tea components and to allow fractions of less complexity be obtained. A degree of resolution has been achieved for TR fractions, unresolvable with reverse phase HPLC, using size exclusion HPLC. Calibration of the column suggested there may be little material above 2,000 daltons associated with the TR. Two heterogeneous TR fractions have been subjected to Porter's autoxidative assay for proanthocyanidins. The resulting solutions were analysed by reverse phase HPLC and shown to contain proanthocyanidins (9.4 and 16.1 %) and galloyl ester (7.1 and 7.4 %), some 73 and 84 % remains uncharacterised. A novel group of yellow pigments has been isolated for which the name theacitrins (TC) has been proposed. Data are presented that suggest the TC are possibly derived from the TF by oxidative opening of the dihydroxybenzene ring associated with the benztropolone structure. The contribution of the phenolic pigments to tea cream was investigated using reversed phase HPLC and found to be ? 86 % TR, 12 % TF and 2 % FG. Evidence is also presented for a synergistic interaction between TF and TR during cream formation. A method has been developed, using caffeine precipitation, for the isolation of TR material that is free from TF and FG Tea pigments have been stored in aqueous solutions to evaluate their potential for use as commercial colourants. The TF and TC were found to possess poor stability. The FG exhibited greater stability but possess low tinctoral power and poor water solubility. Many of the stability trials exhibited a darkening of colour associated with an increase in unresolvable TR material. Storage of an aqueous solution of a TF enriched fraction at 37 °C resulted in the production of unresolvable (TR-like) material. This material was found to possess molecular weights in excess of 2,000, indicating polymerisation. Evidence is presented to suggest the involvement of galloyl groups in the formation of non-hydrolysable bonds within this polymeric material.

There is a disconnect between information technology (IT) and information systems (IS) that lies at the foundation of frequent failure in cost, schedule, and/or performance of IT/IS. This disconnect can perhaps be reconciled through a focus on the socially constructed and emergent nature of IT as it enters and is used by an organization. The argument is that IT investment is not working with the right knowledge for evaluation and justification and does not reflect human nature in decision-making. The hypothesis is that a structured dialog technique, by focusing on properly perceiving human felt needs rather than exclusively technological aims, improves the process of IT project evaluation and justification. This breaks the requirements development process into multiple, time-efficient steps in order to properly acquire and convert tacit knowledge into explicit and then embedded knowledge. The research questions include: What are the foundations of IT/IS failure, and how do they relate to the absence or presence of structured dialog? What are the dimensions of structured dialog that help fulfill the gap between users' felt needs and IT specifications? Finally, what are the aspects of tools and methods applied in early investment lifecycle activities that can, or seem to, fulfill these dimensions? This study posits a conceptual decision framework using structured dialog to perhaps prevent IT failure. The research starts with an analysis of IT/IS failure factors using a metaevaluation approach tailored for qualitative, interpretive analysis as a metainterpretation with respect to IT case studies and a synthesis of those factors. Then, a pilot of a survey approach is performed to profile and test elements of structured dialog and associated early lifecycle tools with the business/mission process community and technologists. This is then made practical by creating a conceptual decision framework for management to use in framing complex investment decisions such as IT investment. The framework includes obtaining early clarification of the purpose of the new IT/IS system, improving team dynamics to enable better collaboration, making a specific, shared decision as the basis of collaboration, and focusing on structured dialog. The elements of structured dialog found to underlie this decision framework are the production and use of shared meaning, creation and use of common language, repetition and continuation of dialog, and facilitation of shared experience. These elements achieve an organizational epistemology, or knowledge framework, that can potentially facilitate more accurate acquisition and development of IT (that is, the system-as-created), and perhaps lay the foundation for subsequent transition into IS (that is, the system-as-used) that an organization should use in the manner needed and intended. In addition, this epistemology underlies the process, and products, of successful IT/IS architecture. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The pathogenesis of renal lesions induced by two types of papillotoxin was examined in male laboratory rats. The compounds used were halogenated alkylamines such as 2 bromoethanamine, or aromatic amines such as diphenylamine (DPA) and N-phenylanthranilie acid (N-PAA) - the latter of which was studied as a model of the fenamate nonsteroidal antiinflammatory drugs. Structure activity studies with haloalkylamines identified three new papillotoxins: 2-chloroethanamine, NN dimethyl 2-chloroethanamine and 3-bromopropanamine. The biological alkylating activities of these compounds (as measured by direct acting mutagenicity) correlated directly with papillotoxicity strongly implicating direct alkylation of papillary tissue in the mechanism of renal papillary necrosis (RPN). DPA and N-PAA induced RPN and proximal straight tubular necrosis after a single dose (lg/kg) or with more protracted administration (250 mg/kg for several weeks). A time course experiment with DPA demonstrated degeneration of the papillary vascular endothelium within three hours and RPN within nine hours. DPA also induced a marked Heinz body haemolytic anaemia, which developed independently of the renal lesions. Two hydroxylated derivatives of DPA were not papillotoxic, but did induce proximal tubular necrosis suggesting that an intermediate of oxidative metabolism is responsible for papillotoxicity. It is hypothesised that RPN results from co-oxygenative metabolism of aromatic amines in the vascular endothelium, during the synthesis of PGI2, and that benzoquinoneimine or semiquinone-type radicals are the proximate toxins. It is further hypothesised that proximal tubular necrosis may result from Cytochrome P-450 mediated epoxidation. The role of Tamm-Horsfall glycoprotein in relation to RPN and interstitial nephritis was examined in animals with ureteral obstruction. The present results, and a reexamination of the tissues from an earlier two year feeding experiment with DPA, strongly implicate RPN in the genesis of so called polycystic renal lesions.

The purpose of the qualitative multi-case study design study is to add to the body of knowledge by exploring how MNCs in the United Kingdom, Ireland, France, Germany, Belgium, and Switzerland (a) employ global approaches in their foreign market operations and (b) differ in their outcomes in international activities compared with their corresponding domestic operations. Findings from the study have shown that cultural differences between the home and host companies have a profound effect on the internationalization strategy. Most of the managers included in the study reported that their organizations encourage diversity and cultural competencies. They also recommended conducting a feasibility study to gain an in-depth understanding of the cultural influences that affect the internationalization plan for their respective MNCs. Feasibility studies and adequate planning allow MNC leadership/management to prepare adequately to navigate the complexities of the foreign culture being aware of the cultural norms and values. Second, the study has also highlighted the need of aligning the strategic plan of the MNC with the local culture. The alignment is necessary to ensure that MNCs develop strategic plans and goals that are responsive to the underlying cultural norms and values of the host country. The greatest challenge for MNCs is merging the local and global internationalization plans to achieve strategic goals.

This dissertation explores the fundamental characteristics of a system of geometry and proportion currently used by Maya house builders and shamans to design vernacular architecture in indigenous Maya communities. An extensive examination of Pre-Columbian Maya art and architecture demonstrates how this system of geometry and proportion was also used by the Maya of the Classic and Post-Classic periods. The dissertation concludes with a brief discussion of how Maya geometry was, and is, an expression of Maya cosmology and religion.