................................................................................................................................... ii DEDICATION ............................................................................................................................... iv ACKNOWLEDGEMENTS ............................................................................................................ v TABLE OF CONTENTS ............................................................................................................... vi LIST OF TABLES ......................................................................................................................... xi LIST OF FIGURES ..................................................................................................................... xiii LIST OF ABBREVIATIONS ...................................................................................................... xiv CHAPTER ONE ............................................................................................................................. 1 1.0. GENERAL INTRODUCTION ............................................................................................ 1 CHAPTER TWO ............................................................................................................................ 6 2.0. LITERATURE REVIEW .................................................................................................... 6 2.