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Quantum dot encoded microspheres (QDEMs) offer much potential for bead based identification of a variety of biomolecules via flow cytometry (FCM). To date, QDEM subpopulation classification from FCM has required significant instrument modification or multiparameter gating. It is unclear whether or not current data analysis approaches can handle the increased multiplexed capacity offered by these novel encoding schemes. In this thesis the drawbacks of currently available data analysis techniques are demonstrated and novel classification methods proposed to overcome these limitations. A commercially available 20 code QDEM library with fluorescent emissions at 4 distinct wavelengths and 4 different intensity levels was analysed using flow cytometry. Multiparameter gating (MPG) a readily available classification method for subpopulations in FCM was evaluated. A support vector machine (SVM) and two types of artificial neural networks (ANNs), a multilayer perceptron (MLP) and probabilistic radial basis function (PRBF) were also considered. For the supervised models rigorous parameter selection using cross validation (CV) was used to construct the optimum models. Independent test set validation was also carried out. As a further test, external validation of the classifiers was performed using multiplexed QDEMs solutions. The performance of MPG was poor (average misclassification (MC) rate = 9.7%) was a time consuming process requiring fine adjustment of the gates, classifications made on the dataset were poor with multiple classifications on single events and as the multiplex capacity increases the performance is likely to decrease. The SVM had the best performance in independent test validation with 96.33% accuracy on the independent testing (MLP = 96.12%, PRBF = 94.38%). Furthermore the performance of the SVM was superior to both MPG and both ANNs for the external validation set with an average MC rate for MLP = 6.1% and PRBF = 7.5% whereas the SVM MC rate was 2.9%. Assuming that the external test solutions were homogenous the variance between classified results should be minimal hence, the variance of correct classifications (CCs) was used as an additional indicator of classifier performance. The SVM demonstrates the lowest variance for each of the external validation solutions (average σ 2 = 31479) some 50% lower than that of MPG. As a conclusion to the development of the classifier, a user friendly software system has been developed to allow construction and evaluation of multiclass SVMs for use by FCM practitioners in the laboratory. SVMs are a promising classifier for QDEMs that can be rapidly trained and classifications made in real time using standard FCM instrumentation. It is hoped that this work will advance SAT for bioanalytical applications.

In 1992 the police service of England and Wales introduced basic interviewing training for police officers. Training was based on the mnemonic PEACE (Planning & preparation, Engage & explain, Account, Closure, & Evaluation) providing an interview structure, and the name of a five day experiential course. The course included guidance on interviewing suspects and witnesses, incorporating good practice from research in the fields of social, cognitive and occupational psychology. A pre release evaluation based on pre and post course assessments, found that PEACE training improved interviewing skills and knowledge (McGurk, Carr & McGurk, 1993). However, subsequent unpublished studies found that PEACE training was not having the positive impact that had been found in the initial evaluation (e.g. Jones, 1996; Rigg, 1999). The research reported here set out to clarify whether PEACE training was improving police interviewing skills, and if it was not, identify the skills gaps. Initially a survey was conducted to determine the number of police officers trained to use PEACE. This was followed by an analysis of 177 real interviews with suspects of crime, using a specially constructed rating scale. In addition, a sample of 75 real interviews with witnesses were analysed with a separate rating scale. Further, analysis was then conducted, to examine the interview process with witnesses, on a subset of 10 witness interviews concerning the crime of assault. Finally, a Behaviourally Anchored Rating Scale (Smith & Kendell, 1963) was developed for assessing interviews with suspects. Training had little impact on officers’ interviewing skills for interviews with either suspects or witnesses. Workplace supervision by police officers was found to improve communication skills and interview structure for interviews with suspects. This finding adds to the developing literature on the importance of ongoing supervision for investigative interviewing. However, the checklist use by the police service for assessing such interviews was found to be flawed. Interviews with witnesses were of a poorer quality than those with suspects. It was established that good practice, for example the Cognitive Interview (Fisher & Geiselman, 1992), was not used in real interviews, which seemed instead to follow the Standard Police Interview (George, 1991). Interviewers conducting real witness interviews relating to bulk crime focussed on statement taking rather than interviews. It is hypothesised that officers’ schema for statement taking is stronger than for interviewing.

Negotiating with insurgents can be a perilous endeavor and talks do not always succeed in ending the conflict. A comprehensive review of the counterinsurgency (COIN, henceforth) literature reveals an emphasis on “how to win” in COIN, in addition to an overrepresentation of the same handful of case studies—Algeria, Malaya, Vietnam—with little to offer in the way of concrete policy prescriptions regarding conflict resolution. By examining four more recent insurgencies (Northern Ireland, Lebanon, Sri Lanka, and South Africa) and the operational and organizational capacities of each group, this dissertation identifies several factors related to an insurgent group’s likelihood of negotiating with the host-nation government, including sanctuary, financing, group composition, popular support, and a military stalemate. After completing a cross-case comparative analysis of the four groups, policy implications and recommendations are provided for the Afghan Taliban. This research relies on archived documents, books, journal articles, semi-structured interviews with subject matter experts, media accounts, and other open sources in order to outline specific conclusions and recommendations while also providing decision-makers with a foundation for related policy on how to approach negotiations with insurgents, both now and in the future.

Kingston is a city facing serious environmental challenges. In common with other Third World cities, these have usually been documented from the perspective of affluent and powerful urban residents. Very little research has explored the spatial and social distribution of environmental problems in the city, or has examined the ways that individual citizens from a variety of backgrounds understand the urban environment. These problems have often been packaged as discrete issues, when in fact they cannot be understood or alleviated without knowledge of their economic, political, and cultural aspects. Urban environmental problems require political solutions that address uneven power relations and ineffective structures of urban governance. In this thesis, I address these issues in Kingston through an application of the themes of nature, power and participation. A mixture of qualitative and quantitative methods were used to explore the ways in which urban residents from different age, gender and class backgrounds construct the city and its environmental problems. The knowledge of marginalised individuals and groups is placed in the foreground and is used to provide an alternative analysis of Kingston’s ecology. These understandings are then used to assess critically the structures of urban governance, and to suggest possible changes that could be made to these. The research confirms that there are significant environmental problems in Kingston, and that these have serious negative impacts on many urban residents. It shows that these problems are understood differently by the various social groups within the city, and that the burdens of environmental problems vary socio-spatially across the Kingston Metropolitan Area. Despite this, there is a general consensus that environmental improvement is desirable. However, for this to be achieved there need to be fundamental alterations in the social structures and political organisation of the city.

This thesis is a study of free people of colour during the era of emancipation in Barbados, with a particular focus on their relationships with and attitudes towards slaves. It examines the period between the 1816 slave rebellion and the 1854 cholera epidemic, encompassing the apprenticeship period of 1834-1838. The thesis argues that differences of class, political ideology, gender and the specific nature of their relationships with slaves determined emancipation's impact on free people of colour. At the same time, the thesis illustrates that pre-emancipation free people of colour as a group remained economically and politically marginal after emancipation, much as they had been during slavery. Reforms to the island's slave laws during the 1820s and early 1830s undermined the legal distinction between free people of colour and slaves. The abolitionism debate and increasing racial tension in the island led free non-whites to challenge openly the principle of racial subordination for the first time. After 1834, elite free people of colour forged a sense of "race consciousness", and adopted emancipation as the key to their battle against racial inequality, asserting themselves as the legitimate protectors of ex-slaves' interests. However class differences and disagreements over emancipation policy led to political factionalism among people of colour. The absence of fundamental change in the distribution of land and wealth after emancipation left most pre-1834 free people of colour and ex-slaves with little hope of political enfranchisement or socio-economic betterment. By the early 1850s, many came to see emigration as the solution to their difficulties. This thesis is the first study of pre-1834 free people of colour in post-emancipation Barbados, and one of few to examine both the periods of slavery and postemancipation. By focussing on the intricate relations between free people of colour and slaves/ex-slaves, this thesis shows how emancipation transformed many aspects of social relations in Barbados ― particularly with regard to race, class, labour and gender.