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This study focuses on the nest site of a poorly known endemic subspecies of orange-crowned warbler (Vermivora celata sordida). The research took place during 2006 on Santa Catalina Island, part of the Channel Island archipelago in Southern California. As one of the first detailed descriptions of the nest site characteristics of this subspecies, this study has revealed that nest placement is highly variable, particularly when compared to mainland populations. Nest height on Catalina ranges from ground to 5m, whereas mainland subspecies nest predominately on or close to the ground. This research also provides an extremely comprehensive analysis of materials used in nest construction and reveals surprising plasticity in the types and amounts of materials used.
Measurements of the nest site uncovered a significant preference to place the ...
A fast and efficient synthetic route was developed for the synthesis of a novel class of enone-containing alpha-amino acid. An amino acid-derived beta-ketophosphonate ester was subjected to Horner-Wadsworth-Emmons conditions using a variety of aldehydes to produce a diverse library of alpha,beta-unsaturated amino acids. E-Configured enone-containing amino acids were also deprotected using a two-stage approach to give the parent alpha-amino acids. A minor modification to the route enabled the synthesis of Z-configured enones via the Still-Gennari reaction. A small library of Z-enones was produced using various aldehydes.
Enone-functionalised alpha-amino acids were employed as substrates for an intramolecular cyclisation reaction to generate 6-substituted-4-oxopipecolic acids. A diastereoselective one-pot reductive amination/cyclisation...
Quasi-brittle failure is characterised by material degradation, fracturing and potential interaction of fragmented parts. The computational description of this behaviour has presented significant challenges to the mechanics community over the past few decades, driven by the development of technology, the increasing social and economical constraints for safer and more complicated engineering designs and consequently by the increasing requirements for more accurate understanding of macro- and micro-structural processes.
Finite element methods have been pushed to their limits in an attempt to resolve strain localisation and ultimately fracturing in a unified and objective manner, while discrete methods have been utilised by artificial connection of discrete bodies which are identified a priori to act as continua. Neither of these attempt...
The incidence of neoplasia at the gastroesophageal junction has increased markedly over the past 20 years, but the mutagen responsible for this remains unknown. Human saliva contains substantial quantities of nitrite and is the main source of nitrite entering the stomach. It is derived from the enterosalivary recirculation of dietary nitrate and its reduction by buccal bacteria. Carcinogenic N-nitrosocompounds may be formed from the nitrite in swallowed saliva by bacterially-catalysed nitrosation in the achlorhydric stomach or acid-catalysed nitrosation in the healthy acid secreting stomach. Protection against luminal acid-catalysed nitrosation is provided by the ascorbic acid content of human gastric juice which reduces nitrite to nitric oxide (NO). A high luminal concentration of NO generated from salivary nitrite has been shown...
We consider the character of several finite deformations of compressible isotropic, nonlinear hyperelastic materials, specifically azimuthal shear of a thick-walled circular cylindrical tube, the bending deformation of a rectangular block and axial shear of a thick-walled circular cylindrical tube. For each problem the equilibrium equations are applied to the special case of isochoric deformation, and explicit necessary and sufficient conditions on the strain-energy function for the material to admit such a deformation are obtained. These conditions are examined for several strain-energy functions and in each case complete solutions of the equilibrium equations are obtained. The predictions of the shear response for different strain-energy functions are compared using numerical results to show the dependence of the applied shear stress...
The problem of what, if anything, brings continuity of thought to the exhortations found in the New Testament Letter of James has perplexed, and continues to perplex interpreters of this letter. Indeed, for Martin Dibelius the literary character of this letter provided no opportunity for the development, or elaboration of religious ideas. In view of this fact, Dibelius concluded that the Letter of James has no theology. In this present consideration of James, it is demonstrated that Dibelius' view of James as lacking a developed theology is quite mistaken. In contrast to Dibelius' opinion, James' employment and development of convenant thought provides the letter with continuity of thought, as the author uses it to challenge the 'defective' theology of the implied audience, whilst establishing his own alternative theology.
The thesis ...
The aim of this work was to explore an alternative to existing methods of detection for Human African Trypanosomiasis (also known as sleeping sickness). A new approach to diagnostics for sleeping sickness is needed, since the existing methods of detection employed in the field have significant shortcomings in terms of sensitivity, cost or ease of operation.
In this work, the enrichment of trypanosomes from blood using travelling electric fields and the selective lysis of cells using optoelectronic tweezers will be presented. Both techniques allow for the enrichment of trypanosomes from blood samples but the first is more suited for an application as a point-of-care device, while the latter is also applicable to other cell types and offers greater flexibility.
Besides demonstrating and quantifying the experimental results the work inc...
Tackling health inequalities is a policy priority. Research on cancer and particularly oral cancer aetiology has somewhat overlooked this area, in favour of pursuing genetic and 'lifestyle' risk factors. The over-arching aim of this thesis was to investigate the epidemiology of oral cancer in relation to individual socioeconomic status (SES), area-based socioeconomic circumstances, and socioeconomic inequalities. Descriptive epidemiology studies undertaken demonstrated that the burden of oral cancer was increasing across the UK, especially in Scotland, and a socioeconomic gap was widening with those from more deprived communities having significantly greater and increasing incidence of the disease. A systematic review and meta-analysis of the world literature showed that low compared to high SES was associated with significantly elevat...
This study can be regarded as the first study that has focused on exploring citizenship and citizenship education in initial teacher education not only in the Omani context but also in Arabic contexts. Specifically, the main purpose of the present study was to identify the perceptions and practices relating to citizenship education within the initial teacher education programmes for social studies in the seven Colleges of Education. In particular, the research considers the following three issues: (a) the policy context of citizenship education in the educational system in general and in teacher education in particular; (b) the perceptions of stakeholders: the policy-makers, the tutors and the student teachers about citizenship and citizenship education. The perceptions about citizenship education were explored in terms of the rational...
The Scottish Government has highlighted the important role of personal and social development in primary education to promote the social inclusion of children who have poor life experiences (Scottish Office, 1999a). HMIE reports however suggest that there are few opportunities in primary schools in Scotland for pupils with social difficulties to develop personal and social skills (HMIE, 1999, 2001a, 2001b). This study explored the historical development of provision for personal and social development in primary education in Scotland, and carried out a survey of current perceptions and provision for pupils with personal and social needs in primary schools in Scotland. Following this, an investigation of the organisation and impact of three personal and social development initiatives for pupils with personal and social difficulties w...
