BACKGROUND

The global epidemic of cardiovascular disease (CVD) continues to rise, with atherosclerotic CVD remaining the lead cause of morbidity and mortality worldwide, comprising of 29% of all global deaths in 2003. A majority of these deaths were directly caused by coronary artery disease (CAD) or strokes. It is estimated that up to 50% of all deaths and disability due to CAD and strokes could be curtailed by a number of lifestyle and therapeutic approaches that directly target major cardiovascular risk factors.

Atherosclerosis is a systemic disease process involving multiple vascular territories. The presence of established vascular disease, regardless of the territory involved, portends the greatest risk of incident cardiovascular events. The prevalence of asymptomatic coronary stenoses of greater than 50% angiographic severity in non-disabling ischaemic stroke patients has recently been estimated to be 20%, and those patients afflicted with peripheral arterial disease have a probability of death due to CAD and stroke of 55% and 11% respectively. Given the significant systemic plaque burden in these patients coupled with corresponding high event rates, various anti-atherosclerotic and vascular protective therapies have the potential to significantly lower absolute clinical event rates.

PATHOLOGY

Atherosclerosis is a chronic inflammatory condition, characterised by the accumulation of inflammatory cells, lipid and apoptotic material within the arterial wall. The endothelial cell layer, a single cell layer lining the lumen of the vasculature, serves to regulate permeability of the arterial wall, vascular tone and tendency for thrombus formation.

Abstract

Magnesium's role in migraine pathogenesis is well-described, with deficiencies known to promote cortical spreading depression, alter nociceptive processing, and neurotransmitter release and encourage the hyperaggregation of platelets, all major elements of migraine development. Research on magnesium has found it to be a potentially well-tolerated, safe and inexpensive option for migraine prevention, while it may also be effective as an acute treatment option for headaches including migraines, tension- type headaches and cluster headaches, particularly in certain patient subsets. This chapter will review the various aspects of migraine in which magnesium plays a part, as well as numerous studies on the use of magnesium in both headache prophylaxis and in the acute treatment of headaches, offering recommendations in its use in clinical practice.

Magnesium in the Body

Magnesium (Mg), the second most abundant intracellular divalent cation, is a cofactor of many enzymes and is involved in a plethora of cellular functions. It plays a central role in both glucose metabolism and in ATP function. Over 300 enzymes require the presence of magnesium ions for their catalytic action, including all enzymes utilizing or synthesizing ATP, or those that use other nucleotides to synthesize DNA and RNA. ATP exists in cells as a chelate of ATP and a magnesium ion.

In the movie The Net Angela Bennett, played by the actress Sandra Bullock, returns to her hotel in Mexico after being hospitalised for several days following an incident in which her purse, containing her passport and credit cards, was stolen. She goes to the Registration Desk to pick up the key to her room.

Angela: ‘I need my room key for 206 please.’

Clerk: ‘What was the name?’

Angela: ‘Angela Bennett.’

Clerk: (Checking the hotel computer) ‘No, I am sorry, Angela Bennett checked out last Saturday.’

Angela: ‘No, sorry, you don't understand. I am Angela Bennett. I am standing right here. I didn't check out.’

Clerk: ‘I am sorry, it's not on the computer. Let me check my records.’

(Scrolling through information on the computer screen) ‘No. Angela Bennett, she checked out last Saturday.’

Angela: ‘No, I didn't check out. I would know if I checked out. I didn't check out.’

Clerk: ‘According to the computer you checked out. There is nothing I can do for you, ok. I am sorry.’

Introduction

In an environment in which transactions are not based on personal relationships, an individual's identity must be established by providing information that is verified by comparing it to a referent standard. Under a national identity scheme like the NIS, the referent standard is the national identity register, whether it takes the form of a central register as originally planned for the NIR and the ACR, consists of several databases, or uses linked data.

When John Bannon formed his first government in November 1982, he inherited heritage legislation he may not have wanted because of his plan to encourage major building projects for growth in a crane-led recovery from economic recession. Moreover, he would soon learn that debates about historic buildings would not end with the enactment of heritage legislation. Debates about incentives for heritage listing, including compensation for building owners whose properties were heritage listed, were ongoing. Debates also continued about the boundaries of heritage: whether the SA Heritage Act (1978) was intended to protect only iconic buildings of significant architectural merit or whether buildings should also be protected because of their historic or cultural significance, whether historic conservation zones and local heritage registers should be added as a second tier of protection and whether local heritage listing should be voluntary. The debates extended further in the decade as suburban councils gained planning controls through conservation zones and adopted local heritage registers.

These debates began to trouble the SA Heritage Committee, in recommending entries on the Register of State Heritage Items, and the Adelaide City Council as it considered nominations for listing on its register and later during its townscape campaign. While parliament and ACC were committed to protecting the built heritage by 1986, the boundaries of heritage listing remained contested and they divided ACC into pro-heritage and pro-development factions for the remainder of the millennium and beyond.

INTRODUCTION

The introduction of prosthetic grafts has revolutionised the management of vascular disease but graft infection although uncommon, remains a dreaded complication With associated significant morbidity and mortality. Mortality occurs in approximately one third of all vascular graft infections, with mortality highest when an aortic prosthesis is involved. As many as 75% of survivors of an infected aortic prosthesis require amputation of a limb, with the incidence of amputation highest when the infection involves more distal prosthetic grafts. The incidence of graft infections is difficult to quantify as infection may manifest many years after implantation with many reports being isolated or as part of case series. Nevertheless, the reported incidence is in the order of 5%, varying according to the site of operation, being higher when a groin incision is used, or if the procedure is an emergency or a redo procedure. Infection following endovascular stent deployment has been reported although its incidence is considered to be very low.

NATURAL HISTORY OF PROSTHETIC VASCULAR GRAFT INFECTIONS

Early prosthetic vascular graft infections typically occurring in the first four months following placement are relatively uncommon (approximately 1%) and are usually caused by the more virulent micro-organisms, such as S. aureus, E. Coli, Pseudomonas, Klebsiella, Proteus and enterobacter. Late prosthetic vascular graft infections are the result of two possible mechanisms. Firstly, by haematogenous seeding from a septic focus elsewhere or by the prosthetic graft becoming infected with enteric contents following a graft-enteric erosion.

Global imperatives for coastal management

The above quote clearly illustrates the international importance of coastal and marine management. This is one of the major program areas dealt with in Chapter 17 of Agenda 21 (UNCED 1992), which is essentially the United Nations' blueprint for sustainable development (see page 207 for definition and discussion). At the United Nations Conference on Environment and Development (UNCED), often referred to as the ‘Earth Summit’, held in Rio de Janiero in 1992, there was a recognition that the world was beginning to live beyond its ecological means and that rapid action was necessary to avert future disaster (UNCED 1992). In this global context, the coast is particularly important for three reasons.

First, most of the world's population lives around the coast. There have been various estimates for just how many people live around the coast, and these estimates will differ depending on what definitions of ‘the coast’ are used. Agenda 21 (17.3) stated that in 1992 more than half of the world's population lived within 60 km of the coast, and that by the year 2020 this proportion could rise to two thirds. Hinrichsen (1998) quotes a figure of 3.2 billion people living within 200 km of the coast, on about 10% of the Earth's land area, and two thirds of the world's population already living within 400 km of the coast.

The dynamics of coastal systems

The previous chapter noted the difficulty of finding a single definition for the Australian coast. This becomes more complex when we realise that the modern coast is not a static line, even though it is often used as boundary marker. While some changes are very visible to the human eye, more subtle changes that may be just as important are occurring all the time. For this reason it is necessary to consider the time context for any coastal processes so that we can provide useful information that is relevant to coastal management.

At time scales of hundreds of millions of years, continental evolutionary processes have less influence on the coast, although many coastal forms may have resulted from older geological processes. For example, the occurrence of large granite erratic boulders along the South Australian gulf coastline does not relate to modern coastal processes but to glacial processes 250 million years ago. Since that time, Australia has split away from Antarctica and is currently drifting north at a rate of approximately 6 cm per year. A coastal classification based on the longer time scale processes of plate tectonics is discussed below.

At time scales of millions of years there have been major changes, such as the rapid climatic and associated sea-level changes of the last two million years during the Quaternary period.

The first chapter of this book examined some of the global imperatives for coastal management, pointing out that (1) most people live on or close to the world's coast, (2) the global population has a high dependency on coastal resources, and (3) human impact on the coast is already at significant levels and is increasing. The second chapter used a number of Australian coastal examples to stress the need to understand coastal processes in order to formulate effective coastal management strategies. The third chapter then illustrated various forms of human impact on the Australian coast, and noted that many of our coastal problems related to either increased human pressure, a poor understanding of coastal processes and/or inadequate planning and management.

This chapter turns to coastal management principles and practices, and examines how these operate within the complexity of the different roles of Australian governments and interactions with different community and interest groups. This is further complicated by the range of different legislative mechanisms and instruments for dealing with coastal management in each jurisdiction.

The need for management

Given that there is clearly a need for effective coastal management in Australia, how do we go about it? What is coastal management, and what is the difference between that and coastal planning? Are there well-defined methodologies or guidelines for coastal management, and what is considered ‘best practice’ in coastal management?

The answers to these questions are not simple, since coastal management is not just about dealing with coastal impacts from identified coastal resource uses.

The previous chapter focused on the importance of understanding coastal processes in order to better inform coastal management. Although the emphasis was on the processes themselves, the eight coastal examples linked the understanding of coastal processes to the management issues for each of the respective examples. This chapter, however, attempts to place a focus on the human impact rather than the processes but, as will become apparent, it is necessary to place this in context of the coastal processes that are being affected by the impact.

Coastal impacts from our cities

The great majority of Australians live on or near the coast (see figure 3.1) in the east of the continent, in Queensland, New South Wales and Victoria. To a lesser extent there is a population concentration at the south-western tip of the continent. Australia has been an urban country for 200 years, and at the start of the 21st century about 70% of its population lives in urban centres of more than 100 000 people. Almost all these centres are at the coast. This includes all capital cities (except Canberra) and large urban centres such as Cairns, Townsville, Sunshine Coast, Gold Coast, and Wollongong. Smaller towns and cities are also mainly at the coast, and today more than 80% of Australians live within the coastal zone.

The RAC Coastal Zone Enquiry showed that more than half of the total population growth in Australia between 1971 to 1991 (see table 3.1) took place in capital cities, and that growth rates were most rapid in the immediate coastal divisions (RAC 1993b).

This book provides an introduction to Australian coastal management, primarily for university students. It will also be of use to government employees and coastal planning consultants in drawing linkages between coastal processes and management. The book will give a better understanding of Australian coastal issues in a global context and also provide an overview of current Australian coastal management practices. It draws heavily on case studies from different states in order to make the text as relevant and practical as possible.

The first chapter of this book attempts to place Australian coastal management in a global context by outlining the importance of the world's coasts for humans and illustrating the international concern for unsustainable coastal resource use and development-related pressure on coastal ecosystems. This chapter clearly outlines how there is a growing international consensus of the need for integrated coastal management as the most effective way forward for the sustainable use of coastal resources. The factors influencing the recent reform of Australian coastal management are then examined. It is noted that there have been significant international influences, such as global change, integrated resource management, sustainable development, and a call for greater community participation. This chapter then outlines some of the major changes to Australian coastal management that have taken place in the 1990s and notes the complexity of management responsibilities and legislative mechanisms between the Commonwealth, state and local governments. This introductory chapter of the book then asks the question ‘What is the coast?’ and illustrates the diversity of scientific and management definitions, concluding with management definitions of the Australian coastline.

This chapter attempts to take stock of what has happened in Australian coastal management up to the end of 2001, particularly the major changes that took place in the 1990s, and comment on the prospects for managing the coast in the 21st century. The book has, so far, focused on four themes:

1. global imperatives for integrated coastal management and the Australian response

2. the need to understand biophysical coastal processes before attempting to find solutions for anthropogenic coastal problems in Australia

3. the scale and magnitude of human impact on the Australian coast which raises a number of generic management issues together with the need for localised or regional approaches to specific pressures on coastal resources

4. the complexity of coastal management in Australia, involving different roles for the Commonwealth, state, territory and local governments, together with community participation.

First, this chapter of the book examines the current state of coastal management in Australia and comments on selected recent international and national discussions which could produce further change. Some of these are global initiatives such as the Rio + 10 Coastal Conference which took place in Paris in December 2001, or national developments such as recent political discussions of the coastal elements of the future National Heritage trust (Mark II) Program for 2002 onwards. By the time this book hits the shelves, there should also be further comment on coastal management from the UNCED 2002 Conference in Johannesburg, as a follow-up to the significant ‘Earth Summit’ held in Rio de Janiero 10 years earlier.

The Australian coast and its thousands of beaches have an iconic status in the Australian culture and way of life. Most Australians live on or near the coast where there is continuing population and development pressure, particularly along non-metropolitan coastlines. There is also a heavy use of coastal resources and added pressure from recreational users. We need to understand how these activities affect coastal processes so that we can limit our impacts. If we can avoid changing the natural balance of processes as far as possible we are more likely to maintain the iconic status of the Australian coast.

There are some good examples where human impact on the Australian coast has been managed quite successfully but the mechanisms for coastal management vary considerably between the various state and territory governments. There have also been numerous coastal inquiries into how we manage the coast but by the turn of the century there was still no single comprehensive overview of Australian coastal management. In order to fill that void, this book was published in 2003. It has had favourable reviews and has been popular as a text.