No description available.

No description available.

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One of the most common pairs of co-occurring psychological disorders in children and adolescents is anxiety and depression. This high frequency of co-occurrence has led to research examining the structure of anxiety and depression, specifically the shared and unique aspects of these syndromes. The tripartite model accounts for the overlap between the disorders by suggesting that they are related because they share the feature of negative affect or general psychological distress. The model further proposes that they can be differentiated by their unique features of physiological hyperarousal (anxiety) and low positive affect (depression). Factor analytic research has shown that anxious symptoms and depressive symptoms can be structurally distinguished and research on the tripartite model has suggested their conceptual distinction. However, research has not shown that anxiety and depression cluster as distinct symptoms in samples of youth. The current study used cluster analysis to examine the grouping of individuals based on their levels of anxiety and depression. It was hypothesized that four groups would emerge-- anxiety only, depression only, comorbid anxiety and depression, and low/no symptoms. Further analyses using the tripartite model variables provided support of the accurate classification of individuals and this model was shown to be a useful tool in differentiating anxious symptoms from depressive symptoms. Exploratory analyses regarding developmental differences in the structure of anxiety and depression provided mixed support.

by Wong Wing Hung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves [70]). / Acknowledgments --- p.iii / Abstract --- p.iv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- The Coupled-cluster Method --- p.3 / Chapter 2.1 --- Background / Chapter 2.2 --- Basic Idea of the Method / Chapter 2.3 --- Discussion / Chapter Chapter 3 --- Spin-one Heisenberg Antiferromagnet --- p.8 / Paper enclosed： Coupled-cluster / approximation for spin-one / Heisenberg antiferromagnet / Chapter Chapter 4 --- Easy-plane Spin-one Antif erromagnet --- p.10 / Paper enclosed： Coupled-cluster / approximation for the easy-plane / spin-one antif erromagnet / Chapter Chapter 5 --- Conclusion --- p.11 / References --- p.12 / Appendix --- p.13

Catherine Theresa Desmarais

published_or_final_version / Physics / Master / Master of Philosophy

No description available.

Westphalian non-marine bivalves in Nova Scotia inhabited fresh to brackish temporary lakes. A series of lacustrine facies are identified on the basis of the faunas. Myalinid genera including the probably pseudoplanktonic Curvirimula, and Naiadites dominate the middle Westphalian A to early Westphalian B. Carbonicola occurs rarely in the late Namurian to early Westphalian A and is the only reported Anthracosiid. Anthraconauta dominates the upper Westphalian C to early Stephanian occurring in a wide range of sediments. The elongate Anthraconaia arenacea group range through the Westphalian D and occur in coarser lithologies. Small-shell Anthraconaia inhabited ephemeral lake margins. Cluster and principal components analysis are used to classify the faunas. The method requires the measurement of a small number of linear and relatively uncorrelated morphological variables and allows the construction of reproducable pictographs. Three new morphospecies are described. Principal components analysis is used to study morphological variation with respect to palaeoenvironment. Consistent morphological trends occur in Naiadites and Anthraconauta and are considered to have been the product of spat selection and phenotypic changes. With increased turbulence and sedimentation rates, the shell's centre of gravity is shifted towards the anter-umbonal region and the bivalves adopt a semi-infaunal mode of life thus, the morphological changes offer increased stability. Evolution was inhibited by the absence of marine incursions and progressive environmental change. Such palaeoenvironmental changes that did occur were local. Competition may have been of evolutionary importance in younger communities of Anthraconaia. The bivalves are of limited stratigraphical use as compared to the British faunas. In conjuction with micro- and macrofloral work, the Namurian/Westphalian A and Westphalian C/D boundaries are lowered and a possible Cantabrian stage recognised. A correlation with the British Chronozones is attempted.