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PURPOSE: We describe a novel approach to analyze fluorescein angiography to investigate fluorescein flow dynamics in the rat posterior retina as well as identify abnormal areas following laser photocoagulation. METHODS: Experiments were undertaken in adult Long Evans rats. Using a rodent retinal camera, videos were acquired at 30 frames per second for 30 seconds following intravenous introduction of sodium fluorescein in a group of control animals (n = 14). Videos were image registered and analyzed using principle components analysis across all pixels in the field. This returns fluorescence intensity profiles from which, the half-rise (time to 50% brightness), half-fall (time for 50% decay) back to an offset (plateau level of fluorescence). We applied this analysis to video fluorescein angiography data collected 30 minutes following laser photocoagulation in a separate group of rats (n = 7). RESULTS: Pixel-by-pixel analysis of video angiography clearly delineates differences in the temporal profiles of arteries, veins and capillaries in the posterior retina. We find no difference in half-rise, half-fall or offset amongst the four quadrants (inferior, nasal, superior, temporal). We also found little difference with eccentricity. By expressing the parameters at each pixel as a function of the number of standard deviation from the average of the entire field, we could clearly identify the spatial extent of the laser injury. CONCLUSIONS: This simple registration and analysis provides a way to monitor the size of vascular injury, to highlight areas of subtle vascular leakage and to quantify vascular dynamics not possible using current fluorescein angiography approaches. This can be applied in both laboratory and clinical settings for in vivo dynamic fluorescent imaging of vasculature.

Most plant species have a range of traits that deter herbivores. However, understanding of how different defences are related to one another is surprisingly weak. Many authors argue that defence traits trade off against one another, while others argue that they form coordinated defence syndromes. We collected a dataset of unprecedented taxonomic and geographic scope (261 species spanning 80 families, from 75 sites across the globe) to investigate relationships among four chemical and six physical defences. Five of the 45 pairwise correlations between defence traits were significant and three of these were tradeoffs. The relationship between species' overall chemical and physical defence levels was marginally nonsignificant (P = 0.08), and remained nonsignificant after accounting for phylogeny, growth form and abundance. Neither categorical principal component analysis (PCA) nor hierarchical cluster analysis supported the idea that species displayed defence syndromes. Our results do not support arguments for tradeoffs or for coordinated defence syndromes. Rather, plants display a range of combinations of defence traits. We suggest this lack of consistent defence syndromes may be adaptive, resulting from selective pressure to deploy a different combination of defences to coexisting species., CODEN: NEPHA

Most plant species have a range of traits that deter herbivores. However, understanding of how different defences are related to one another is surprisingly weak. Many authors argue that defence traits trade off against one another, while others argue that they form coordinated defence syndromes. We collected a dataset of unprecedented taxonomic and geographic scope (261 species spanning 80 families, from 75 sites across the globe) to investigate relationships among four chemical and six physical defences. Five of the 45 pairwise correlations between defence traits were significant and three of these were tradeoffs. The relationship between species’ overall chemical and physical defence levels was marginally nonsignificant (P = 0.08), and remained nonsignificant after accounting for phylogeny, growth form and abundance. Neither categorical principal component analysis (PCA) nor hierarchical cluster analysis supported the idea that species displayed defence syndromes. Our results do not support arguments for tradeoffs or for coordinated defence syndromes. Rather, plants display a range of combinations of defence traits. We suggest this lack of consistent defence syndromes may be adaptive, resulting from selective pressure to deploy a different combination of defences to coexisting species.

Systems integration is a major endeavor in the development of a system. The goal of integration is to bring separately developed components to create the required system within both the defined schedule and the allocated budget. An entropic approach to assessing the success in attaining the goal, i.e., systems integration success, involves representing the system as a network, whose nodes are the elements of the system and whose links are the connections among the elements, and determining and tracking system network entropy. The work in this thesis considers more than two possible states for each link, explicitly assigning probabilistic measures to systems development and integration activities, and applying it to the integration of a robot used in the detection and destruction of improvised explosive devices. This work demonstrates the feasibility of applying this entropic approach to assessing systems integration success and, specifically, the feasibility of using network entropy as a metric to aid in systems integration., The original document contains color images.

The environmental performance and management disclosure of organisations has over the past decade come under increased scrutiny due to a number of factors including, in particular, the impact organisations have had on the world’s environment and the corresponding rapid change in the world’s climate. These concerns have made organisations, including financial institutions, review the level of their environmental performance and management disclosures to demonstrate, amongst other objectives, their level of social responsibility. Financial institutions due to the nature of their business are not generally seen to contribute directly to the degradation of the environment however they do provide the funds for many organisations’ projects which do directly impact on the environment. This paper will review the environmental performance and management disclosures of two note issuing banks in Hong Kong; the Hongkong and Shangihai Banking Corporation (HSBC) and Bank of China (Hong Kong) Limited (BOCHK) from 2003 to 2006. This review will be conducted with reference to the Equator Principles, a voluntary environmental performance framework, which were developed specifically for financial institutions. The second purpose of this paper is to contribute to the literature on legitimation theory with specific reference to the social constructionalist perspective of legitimation.

The increasing public concern on the state of the world’s environment and the impact of mankind on the ecology of the world has lead to the increased scrutiny of the operations and performance of organisations. Organisations are now expected to be able to demonstrate that they are aware and are addressing the impact of their operations, both direct and indirect, on the environment and society in general. Financial institutions due to the nature of their business generally do not contribute directly to the degradation of the environment however they do provide the funds for many organisations’ projects which do directly impact on the environment. The purpose of this paper is twofold. First, this paper will review the environmental reporting practices of the three note issuing banks in Hong Kong; the Hongkong and Shangihai Banking Corporation (HSBC), the Standard Chartered Bank (SBC) and Bank of China (Hong Kong) Limited (BOCHK) for the period of 2003 to 2006. The evaluation of their environmental reporting practices will be based on the voluntary Equator Principles, first introduced in 2003, which outline how financial institutions can reflect the current environmental and social concerns associated with project funding. Secondly, this paper will add to the literature on the social constructionalist perspective of legitimation theory upon which this study is based. Unlike legitimacy theory, which focuses on the result [legitimacy], this paper will focus on the processes these three banks use to establish a relationship between their actions and their values through the use of environmental performance reports [legitimation].