The caudal fin of zebrafish (danio rerio) is often used to study regeneration thanks to its extraordinary regenerative ability, easy access, and relative simplicity in structure. Branching morphogenesis is observed in many organs, including lungs and salivary glands in mammals, as well as the fin rays in zebrafish and is thought to follow unifying principles. An important developmental gene, sonic hedgehog a (shha), has been shown in other studies to play an essential role in the branch formation. Previous studies in our lab have shown that the transient depletion of the shha-expressing cells following laser ablation of the shha-expressing cells in the regenerating caudal fin results in a delay of fin rays branch formation. In order to study the long-term effect of ablating the shha-expressing cells, I generated a new zebrafish transgenic line (Tg)(2.4shha:CFP-NTR-ABC) to perform a conditional cell ablation using the Metronidazole/Nitroreductase (Mtz/NTR) system. Preliminary data suggest that cell ablation using the Mtz/NTR system is successful in the Tg(2.4shha:CFP-NTR-ABC) embryos. In addition, short-term ablation of the shha-expressing cells through Mtz/NTR system delays branch formation during caudal fin regeneration of the Tg(2.4shha:CFP-NTR-ABC) adult fish. Further work will involve the analysis of the effects of the long-term ablation of the shha-expressing cells and the involvement of other signaling pathways in the ray branching formation during zebrafish caudal fin regeneration. This study can provide insights into understanding of the molecular mechanisms underlying branching morphogenesis in various organs. During the course of the above project, I have observed an organ-wide response to local injury in the zebrafish caudal fin. In this study, I have shown, for the first time, an immediate organ-wide response to partial fin amputation characterized by the damage of blood vessels, nerve fibers and the activation of inflammatory response in the non-amputated tissues. I established that the adult zebrafish caudal fin serves as an excellent model for the study of the organ-wide response to local injury, and such study may provide new insights into the field of regenerative medicine in which stimulating regeneration locally may trigger responses in unintended locations.   Résumé La nageoire caudale du poisson zèbre (danio rerio) est souvent utilisée pour étudier les mécanismes de régénération à cause de son extraordinaire capacité de régénération, son accès facile, et sa relative simplicité structurale. La morphogenèse de branches est observée dans plusieurs organes incluant les poumons et les glandes salivaires chez les mammifères ainsi que les rayons des nageoires du poisson zèbre et est supposée suivre des principes communs. Un important gène de développement, sonic hedgehog a (shha), joue un rôle essentiel dans la formation des branches. Des études précédentes effectuées dans notre laboratoire ont montré que l’absence transitoire des cellules exprimant shha dans des expériences d’ablation au rayon laser induit un délai de la formation des branches dans les rayons au cours de la régénération de la nageoire caudale. Afin d’étudier les effets de l’ablation à long terme des cellules exprimant shha, j’ai fait un nouvelle lignée transgénique de poisson zèbre Tg(2.4shha:CFP-NTR-ABC) pour effectuer une ablation cellulaire conditionnelle à l’aide du système Métronidazole / Nitroréductase (Mtz/NTR). Mes données préliminaires suggèrent que l’ablation cellulaire à l’aide du système Mtz/NTR fonctionne sur les embryons Tg(2.4shha:CFP-NTR-ABC). De plus, l’ablation à court terme des cellules exprimant shha à l’aide du système Mtz/NTR induit un délai de la formation des branches au cours de la régénération des rayons la nageoire caudale des poissons adultes Tg(2.4shha:CFP-NTR-ABC). Des études supplémentaires incluront l’analyse des effets de l’ablation à long terme des cellules exprimant shha et le rôle d’autres cascades de signalisation dans la formation des branches des rayons au cours de la régénération de la nageoire caudale du poisson zèbre. Cette étude pourrait fournir des informations concernant la compréhension des mécanismes moléculaires sous-jacents à la formation de branches dans des organes variés. Au cours de l’étude décrite ci-dessus, j’ai fait l’observation d’une réponse globale de toute la nageoire caudale à une blessure locale. Dans cette étude, j’ai montré pour la première fois, une réponse immédiate et globale après amputation partielle de la nageoire. Cette réponse est caractérisée par des lésions des vaisseaux sanguins, des fibres nerveuses et par l’activation d’une réponse inflammatoire dans les tissus non-amputés. J’ai établi que la nageoire caudale du poisson zèbre adulte est un excellent modèle pour l’étude de la réponse globale d’un organe à une lésion locale. Une telle étude pourrait fournir de nouvelles informations pertinentes à la médecine régénérative qui, en visant à stimuler la régénération de façon locale, peut entraîner des réponses dans des domaines non voulus.

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[Abstract]: In this dissertation, the author has undertaken research involving the executive of the United Firefighters’ Union - Queensland Branch (UFUQ) to develop a practical definition and application for the emerging concept of ‘human security’ and its potential application to the needs of the Union and its membership.The central research questions start by considering the Australian trade union movement’s focus on ‘job security’, before asking whether ‘human security’ represents an evolutionary move that is worthy of their consideration. Subsequent questions examine the Federal Government’s view of globalisation, as a ‘top-down’ approach, and the relationship between trade, security, and ‘the national interest’, before considering the merits of constructing a ‘bottom-up’ approach from the base of civil society, through bodies such as unions. Human security, as a recent addition to security thinking, seeks to empower‘ordinary’ people as active actors in their quest for ‘real’ security, as they seek freedom from both ‘fear’ and ‘want’. This reverses the Realist tradition that demandssecurity be derived ‘from above’, organised within the realm of sovereign states as they fulfil their task of protecting ‘the national interest’. Emerging post-Cold War,human security has been used to argue that the Realist approach to security, involving balance-of-power mechanisms, may be usurped by a more holisticapproach. One that invests people as central actors rather than states, favouring individuals above the territorial entities they inhabit. The current phase ofglobalisation poses various challenges to states’ security, as the physical bordersecurity erodes through technological advance, and new modes of business. The proposed Australia-China Free Trade Agreement (FTA) carries both potentialbenefits and disruptions to the lives of ordinary Australians. But, the debate is unbalanced, largely flowing downwards from the international sphere to individualsbelow. Alternatives generated within civil society struggle for legitimacy, failing the dominant ‘commonsense’ paradigm, as the current hegemony ensures that the mostpowerful tools in the ‘toolbox of power’ are held firmly in the grip of those better positioned to dictate policies.The search for a new definition of human security faltered, as research revealed a lower level of awareness in issues further removed from the firefighter’s control.From this finding emerged a web-based self-education research tool, and later, a simple pictorial tool, the ‘Orbits of Security’. Both instruments were inspired byGramsci’s notion of ‘cultural hegemony’. Both are intended to show the UFUQ membership how, through education, they can begin to assert greater ownership over their personal human security ‘orbit’ by comprehending the nature of ‘cultural hegemony’. The study concludes by arguing that the rightful place of ‘ordinary people’ is atsociety’s core, not at the periphery. In this way, ‘human security’ becomes a useful counter-hegemonic tool for the UFUQ, and a valuable addition to their ‘toolbox ofpower’.

Thesis (M.S.)--State University of New York at Binghamton, Geological Sciences and Environmental Studies of Department, 2007. / Includes bibliographical references.

Techn. University, Diss., 2006--Darmstadt.

Thesis (Ph. D.)--University of New South Wales, 2002. / Also available online.

Zugl.: Darmstadt, Techn. University, Diss., 2008.

Thesis (D. Min.)--Nazarene Theological Seminary, 1989. / Includes bibliographical references (leaf 33).

Thesis (M.S.)--University of Nevada, Reno, 2008. / "May, 2008." Includes bibliographical references (leaves 63-64). Online version available on the World Wide Web.