Angiogenesis, the formation of new blood vessels from pre-existing vasculature, is important in post-injury scar formation but its role in scar-free regeneration remains relatively unexplored. This study investigates vascular regeneration during tail regeneration in the leopard gecko (Eublepharis macularius). It is hypothesized that blood vessel regeneration follows a conserved sequence of events similar to physiological angiogenesis. To test this hypothesis the onset and pattern of expression of common vascular and angiogenic proteins (von Willebrand factor, α-smooth muscle actin, vascular endothelial growth factor, thrombospondin-1 and cluster differentiation 36) was investigated. The effect of the anti-angiogenic peptide ABT-510 on tail regeneration was also explored by documenting changes in vascular morphology and histology of regenerate tails. Results show that the proteins of interest are expressed in a conserved sequence consistent with physiological angiogenesis. ABT-510 did not consistently prevent tail regeneration, but did have some small-scale effects. These results provide the basis for further investigations into the importance of angiogenesis during multi-tissue regeneration.

Transmission impairments degrade the quality of optical signals, ultimately limiting the achievable transmission distance. Optical 3R regenerators provide an effective means of coping with transmission impairments by restoring the quality of optical signals through reamplification, reshaping, and retiming (3Rs), thereby enabling reliable transmission over long distances. Beyond the 3Rs, however, regenerators must also be able to operate within the practical constraints of the network. The specific network of interest in this thesis is referred to as an agile all-photonic network (AAPN). In AAPNs, traffic consists of optical packets that are routed through the core of the network without undergoing optical-to-electrical conversion for signal processing (e.g., 3R regeneration). As a result, 3R regeneration must be performed all-optically, otherwise known as all-optical 3R regeneration (AO-3R). Although a variety of AO-3R techniques have been demonstrated, none have been specifically designed to operate within the practical constraints of AAPNs. In this thesis, a 10 Gb/s all-optical 3R regeneration (AO-3R) technique is proposed, specifically designed to operate within the practical constraints of AAPNs. The technique performs AO-3R in a novel 2-stage design. In the first stage, all-optical retiming is achieved using a self-pulsating distributed feedback laser (SP-DFBL) for all-optical clock recovery and cross-phase modulation (XPM) in highly nonlinear fiber (HNLF) with offset spectral slicing for the retiming. In the second stage, all-optical reshaping (and reamplification) is achieved using self-phase modulation (SPM) in HNLF with offset spectral slicing. Experimental assessment of the AO-3R system performance yields excellent results. In particular, AO-3R is shown to improve the performance of input signals degraded by transmission impairments, such as amplified spontaneous emission (ASE) noise, while providing low sensitivity to input signal properties, such as the state-of-polarization. Furthermore, AO-3R is shown to successfully achieve its ultimate goal for AAPNs – the regeneration of optical packets. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2007-08-09 16:31:25.462

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Neuronal regeneration in the mammalian central nervous system (CNS) is severely compromised due to the presence of extrinsic inhibitory signals and a reduced intrinsic regenerative capacity. Understanding the cellular and molecular processes underlying injury and regeneration in the CNS is necessary for the development of effective therapeutic strategies. Lymnaea stagnalis, a freshwater pond snail, has proven to be a powerful model for studying the fundamental mechanisms underlying neurite outgrowth and regeneration. In this study I designed the first custom L. stagnalis microarray gene chip and carried out microarray analysis to profile gene expression changes following CNS injury. From a pool of significantly regulated genes, I provided the first evidence that C/EBP, a transcription factor, plays an integral role in regeneration by maintaining the viability of the distal neurite. We also proposed a novel signaling network and demonstrated that BCL 7 regulates neurite regeneration, an effect that may be mediated through Ca2+-dependent growth cone formation.

Neuronal regeneration in the mammalian central nervous system (CNS) is severely compromised due to the presence of extrinsic inhibitory signals and a reduced intrinsic regenerative capacity. Understanding the cellular and molecular processes underlying injury and regeneration in the CNS is necessary for the development of effective therapeutic strategies. Lymnaea stagnalis, a freshwater pond snail, has proven to be a powerful model for studying the fundamental mechanisms underlying neurite outgrowth and regeneration. In this study I designed the first custom L. stagnalis microarray gene chip and carried out microarray analysis to profile gene expression changes following CNS injury. From a pool of significantly regulated genes, I provided the first evidence that C/EBP, a transcription factor, plays an integral role in regeneration by maintaining the viability of the distal neurite. We also proposed a novel signaling network and demonstrated that BCL 7 regulates neurite regeneration, an effect that may be mediated through Ca2+-dependent growth cone formation.

The research project studies the impact of urban regeneration in the historic centre of Naples during the 1990s. It examines how the centre-left administration, elected in 1993, harnessed the city's cultural and architectural heritage with the view to encouraging tourism, attracting inward investment and fostering among Neapolitans a sense of civic pride and a greater participation in urban life. It is argued that the reimaging of the built environment during the 1990s entailed re-definitions of citizenship, public space and urban history and the construction of a consensual vision about a 'new' Naples, but that this process was at the same time renegotiated and contested by residents and city users. The research focuses on three key urban sites - two piazzas and a park built after the 1980 earthquake - in order to analyse how the material and discursive consequences of regeneration led to conflicts over meanings and uses of public space. These case studies involved extensive periods of observation and interviews as well as consultation of newspapers and historical material. The study of Piazza Plebiscito, a former car park pedestrianized in 1994 and since officially adopted as the city's new symbol, examines disparate notions of heritage and urban decorum. Piazza Garibaldi, located in front of the main railway station and reconceived during the 1990s as the 'gateway' to the historic centre, analyses the relationship between immigrants and the piazza and the representation of such groups in debates about the regenerational city. Lastly, DAMM, an occupied centro sociale ('social centre') situated in an abandoned neighbourhood park, examines both the representation of the central popular quarters in debates about the city's renovation and the attempts by a group of local residents and young people to organize an alternative public space.

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Public spaces, which have been one of the integral components of cities for centuries, have become subject to broad concern for more than two decades. Particularly under the shadow of globalisation and privatisation, attractive and alluring public spaces have been placed at the centre of the major world cities and the old-industrial cities competing as part of a search for new niches in the competitive urban markets. Starting from the late-1970s, the significance of public spaces has also been increasingly recognised by the central and local governments in Britain. A number of `well-designed' public spaces were developed especially through the regeneration and revitalisation schemes of the derelict lands of industrial estates, declining waterfronts and city centres. The recent interest in British public spaces is a promising sign, as the decline and decay had lately become their predominant characteristics. Nevertheless, it raises major questions about their `publicness'. As an outcome of these questions, this thesis focuses on the problem of the `publicness' of the 1990s public spaces in Britain. It concentrates on the two recently developed public spaces in the city centre of Newcastle upon Tyne. By employing the case study method as a research strategy, this research, first, examines the history of the two public spaces, as well as their physical, psychological, social, political, economic and symbolic roles and problems just before the recent redevelopment schemes began. Then, it analyses the `publicness' of the recent development schemes of both public spaces through i) planning and design, ii) construction, iii) management and maintenance, iv) use phases with regard to the criteria of `access', `actors' and `interest'. Here, it mainly tries to see whether the `publicness' of the public spaces has reduced or increased with the recent development schemes. Finally, comparing one case to another, it seeks to show the similarities and differences of both public spaces in terms of the change in their `publicness' with the recent development schemes. The findings of the research lead us to draw the conclusion that, with the recent development schemes, both cases turned into `good-looking' and `well-maintained', but `less' public spaces than they used to be.

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