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Meat and milk from sub Saharan African cattle systems tend to have high greenhouse gas emissions intensities; this is largely due to low levels of productivity. There is a need to increase production to meet an increasing demand for livestock commodities; driven by growing populations, and growing diet variation, as incomes and urbanisation increase. Without measures to reduce the emissions intensity of production, there will be significant increases in total greenhouse gas emissions. Therefore, cost-effective ways of reducing emissions intensity, whilst increasing productivity should be identified. This thesis looks to support this by providing an assessment of low-input to semi-intensified cattle production systems in Senegal, West Africa; where cattle populations are growing and efforts are being made to increase domestic milk production. The emissions intensity of protein from current production systems is calculated using a version of the Food and Agriculture Organization’s Global Livestock Environmental Assessment Model (GLEAM). Variation in emissions intensity is observed between current systems, which can be largely linked to feed ration quality and levels of protein productivity. Productivity improving interventions suitable for the study systems are identified, and their application to current systems modelled by altering input parameters within GLEAM. It is suggested that production systems could reduce emissions intensities by applying nutritional and health related intervention packages; through which the varying production systems could abate between 10% and 20% of their total greenhouse gas emissions whilst also making financial savings. A comparison between the current systems of production also suggests that changing the lower productivity systems to match higher producing systems would also offer substantial cost-saving emissions abatement. The thesis considers the key limitation to the use of GLEAM for modelling the application of nutritional mitigation measures, in that when nutritional improvements are made animal performance does not currently increase. Predicting how animals will respond to improved nutrition is challenging. However, a methodology is discussed, and is shown to have an important effect on the emissions abatement results. Subsequently, the thesis advocates further research to experimentally substantiate animal performance responses when nutritionally limited cattle are given improved feed regimes. Despite the study livestock keepers showing aspiration to improve the productivity of their herds, with subsequent potential to reduce greenhouse gas emissions, the thesis recognises that the abatement potentials suggested by modelling would be restricted by the reality of production system context and constraints. Key barriers to a realisation of the productivity improvements include: a lack of financial means, limitations to resource access and affordability, and requirement for information and training concerning productivity improving options. For realisation of productivity improvements the current barriers would require further investigation, the thesis helps identify what form interventions should take.

Cell therapy is a progressively growing field that is rapidly moving from preclinical model development to clinical application. Outcomes obtained from clinical trials reveal the therapeutic potential of stem cell-based therapy to deal with unmet medical treatment needs for several disorders with no therapeutic options. Among adult stem cells, mesenchymal stem cells (MSCs) are the leading cell type used in advanced therapies for the treatment of autoimmune, inflammatory and vascular diseases. To date, the safety and feasibility of autologous MSC-based therapy has been established; however, their indiscriminate use has resulted in mixed outcomes in preclinical and clinical studies. While MSCs derived from diverse tissues share common properties depending on the type of clinical application, they markedly differ within clinical trials in terms of efficacy, resulting in many unanswered questions regarding the application of MSCs. Additionally, our experience in clinical trials related to critical limb ischemia pathology (CLI) shows that the therapeutic efficacy of these cells in different animal models has only been partially reproduced in humans through clinical trials. Therefore, it is crucial to develop new research to identify pitfalls, to optimize procedures and to clarify the repair mechanisms used by these cells, as well as to be able to offer a next generation of stem cell that can be routinely used in a cost-effective and safe manner in stem cell-based therapies targeting CLI.

In all fields of wildlife research and management, fundamental biodiversity and species distributional data are required. Yet, the difficulty that wildlife researchers face detecting small and cryptic species, in particular snakes and lizards (squamates), has led to gaps in fundamental knowledge. The lack of fundamental ecological data limits our understanding about the role many squamates perform in ecosystems and diminishes our ability to manage potential threats. Indeed, the dearth of squamate data is so pervasive that the global threat to squamates in 2015 could not be assessed. This situation is of great concern since squamates are a particularly speciose vertebrate group. Collecting fundamental data on squamates is ordinarily achieved with capture, trapping, or visual encounter methods. These methods are often costly, since researchers need to remain in the field for protracted periods, and are ethically questionable due to direct and indirect impacts on target and non-target fauna. Thus, developing survey methods that can effectively, efficiently, and ethically provide fundamental data are paramount for squamate research and management. The most direct solution to ameliorate data deficiency is to improve detection methods and the most direct solution to improve detection methods is to adopt new technologies. In recent decades camera-traps have become a valuable tool for monitoring mammals, fish, and to a lesser extent birds. For example, camera-traps are both more effective and more cost-effective than labour-intensive methods, such as live-trapping, for detecting numerous mammal species. However, the use of camera-traps to monitor squamates hitherto has been limited. While camera-traps have real limitations, their use for detecting squamates has been limited due to misconceptions about camera-trapping technology. It might be that camera-traps are as useful for monitoring squamates as they have been for other taxa, but considerable research might be required to develop an effective method. Hence, this thesis addresses the following question: Is camera-trapping a cost-effective and ethical method for monitoring terrestrial squamates? As camera-traps had not been used to monitor a squamate assemblage, a suitable method needed to be developed. The method would need to detect the range of squamate species occurring in an area, including small species (snout-vent length ≤ 50 mm), and generate ecologically meaningful data. By reviewing how camera-traps function at a technical level, and assessing attempts to use camera-traps for detecting ectothermic species, the Camera Overhead Augmented Temperature (COAT) method was developed. The COAT method positions the camera-trap so as to take overhead images of squamates as they pass under the camera-trap. In the first field trial, the COAT method detected the majority of squamate and mammal species known to occur on the study area. Detections included small squamates with a SVL ≤ 50 mm. Most species could be identified to species-level, and several species could be identified to individual-level. While the results were encouraging, the pilot study did not address the main question of the thesis. With development of the COAT method, the next logical step was to compare the COAT method to existing standard squamate-survey methods to assess whether camera-traps were effective. As a first comparison, the COAT method was compared to cage and Elliott traps and artificial refuges. These labour-intensive methods had been used on the study area since 2011 as part of a long-term monitoring program. The COAT method was found to be more effective and more cost-effective than the labour-intensive methods for detecting squamates and mammals simultaneously, and mammals alone. The COAT method was no more, but importantly, no less effective than the labour-intensive methods for detecting squamates alone. There was weak evidence that the COAT method was more cost-effective than the labour-intensive methods for squamates alone. Importantly, given that several mammal and squamate individuals perished in the labour-intensive methods survey, the COAT method was ethically superior. Despite the encouraging results, six aspects of Version 1 of the COAT method were identified as areas requiring improvement or further analysis. Three aspects related to the instrument (i.e., camera-trap) and three related to the concentration methods. To improve the COAT method the time-lapse trigger, a more sensitive passive infrared (PIR) trigger, and adjusted camera focal length were examined. Both the time-lapse trigger and more sensitive PIR trigger increased squamate detections. Unfortunately, regardless of sensitivity the PIR sensor resulted in biased detections, which the time-lapse trigger did not. It was also revealed that by adjusting the camera’s focal length all squamates, including small species, could be identified to species-level. Thus, the second version of the COAT method dictated that both time-lapse and PIR triggers be used simultaneously, and camera focal length be adjusted. When first designed, two concentration methods were included in the COAT method. Bait, specifically peanut butter and oats, was included to attract mammals, and drift fences were included to channel fauna to the detection zone. Additionally, a cork floor tile was positioned in the detection zone of the camera-trap. It was included to create a thermal contrast between fauna and the background substrate, necessary for the camera-trap to trigger. However, the tile appeared to function as a concentration method. While inclusion of each component was logical, their effects on squamate detections were not empirically tested. Thus, three further field experiments were conducted. The presence of bait and drift fences did not affect squamate detections. Both the presence and material of the tile affected squamate detections. Whether the tile functioned as a concentration method was not clear and could not be explored within the scope of this thesis. Although these experiments did not directly improve the COAT method, they deepened the understanding of how the COAT method functions, and highlighted future research directions. Given the improvements made to the COAT method, a final comparison was required to provide a definitive answer to the main question of the thesis. The COAT method was compared to artificial refuges and pitfall traps. Version 2 of the COAT method was both more effective and more cost-effective than the labour-intensive methods examined for inventorying the squamate assemblage. More squamate species on average were detected per transect with camera-traps than with artificial refuges or pitfall traps. Over the entire survey, all 10 squamate species were detected with camera-traps, yet only seven and six squamate species were detected with artificial refuges and pitfall traps respectively. Again, camera-traps had less impact upon fauna as several squamates and amphibians perished in pitfall traps. With this final comparison, the central question of the thesis could be confidently answered in the affirmative. Development of the COAT method has several important implications. First, this is the first camera-trapping method that can be used to monitor a squamate assemblage. This provides wildlife researchers with a new tool to address both existing and new types of questions. Camera-traps have been used to great effect in mammology, and the COAT method should provide herpetologists those same benefits. Second, by being more cost-effective, the COAT method will save precious research funds and should increase data collection overall. Lastly, the COAT method detects both squamates and mammals simultaneously. Wildlife researchers currently using camera-traps to monitor small-mammals can use the COAT method and include squamates as target fauna. Results from this research are encouraging and provide a critical first chapter in how camera-traps can be utilised to monitor squamates.

As watersheds are urbanized, most of their surfaces will be paved. The impervioussurfaces will reduce water infiltration, thereby, increasing the volume of surface runoff.Best Management Practices (BMPs) are used to mitigate these effects of urban land use byretaining large volumes of stormwater runoff.With continued urban development and the impending changes in our climate, it isessential to have a better knowledge of the effectiveness of BMPs in reducing surfacerunoff under different climate conditions. As construction and implementation of BMPs isoften very expensive, this information will be especially useful in planning long-termdevelopment projects and in devising appropriate mitigation strategies to combat futurechanges in our environment.In this study, the main objective was to explore the most cost-effective arrangementof BMPs in reducing stormwater quantity under current and future climate regimes. TheLudlow watershed in Kenton County, northern Kentucky, was selected as a case study. Adecision-support system, System for Urban Stormwater Treatment and AnalysisIntegration (SUSTAIN) (US EPA 2009b), developed by U.S. Environmental ProtectionAgency, was used as an assessment tool. A SUSTAIN model for the study area was firstdeveloped, calibrated, and validated. It was then used to identify the most cost-effectiveBMPs arrangement under the current land use and climate conditions. To ensure that these BMPs will still be appropriate in alleviating future water resources problems, this study also simulated the hydrologic conditions under future climate conditions. The future climate scenarios were developed based on the Intergovernmental Panel on Climate Change (IPCC) Annual Report 4 (AR4) B1 climate scenario (IPCC AR4 2007).The results of this study reveal the most cost-effective configuration of BMPs in the Ludlow watershed. By simulating the effectiveness of the BMPs in 2030 and 2050 under future climate change scenarios, the findings shed lights on the most appropriate BMPs design. This information may be useful to resource managers and planners in deriving sound water management policies.

Data on the web is increasingly being made available in a semi-structured format which presents some challenges for effective extraction of information [ABS00]. Semi-structured data is not rigidly formatted, i.e., it is not strictly table-oriented as in a relational model or other conventional database systems [A97]. The structural or hierarchical relationship between elements in semi-structured data typically needs to be preserved. In traditional databases, the records do not bear any inherent ordering or structural relationships. Moreover, traditional database schemas are not contained within the data itself. Owing to these reasons, one challenge is to store semi-structured data efficiently and another is to query this data effectively. A data model for representing such data is the XML data model [XML]. It supports modeling both the structure and the data contained within it.There are several methods of querying XML data. While some methods use XML data in its native format, others transform it into another format before it can be queried. However, there is an absence of a common ground where an informed decision can be made about the selection of the best query method. There is a need to make this decision based on the comparison of significant factors or parameters for each query method in order to confirm that the selection of a query technique is expected to perform better than another technique. Based on Richardson's algorithm [R09], our work focuses on implementing this recommendation in a cost-effective manner to result in the selection of an appropriate query technique pertaining to the given scenario.

Uncorrected refractive error (URE) is the leading cause of vision impairment globally. URE, particularly uncorrected presbyopia (resulting in near vision impairment), has been a poorly recognised, poorly researched and a poorly prioritised area. This thesis explores the impact and cost-effectiveness of URE correction. In the health sector, cost-utility analysis is a form of cost-effectiveness evaluation that considers a person’s Quality of Life (QoL) outcomes. These types of evaluations assist governmental resource allocation decisions. A utility value is an indirect measure of a person’s QoL. Utilities have been derived for a variety of ocular and medical conditions but not previously reported for URE. Cross-sectional research involving 406 refractive error participants was conducted at a university based eye clinic in Sydney. Eye examinations and utility interviews and questionnaires were administered on all participants. Utilities were elicited using the Time-Trade-Off (TTO), Visual Analogue Scale (VAS) and AQol-7D methods. URE was found to be associated with measurable reductions in QoL using utility analysis. Unaided visual acuity (VA) was found to be a strong predictor of utility with little influence of socio-demographic and lifestyle factors. This suggests results may be generalised to other populations based on the level of VA loss. Reductions were similar irrespective of whether near or distance vision was impaired but worse when both aspects of vision were affected. This thesis therefore argues for the inclusion of near vision impairment to current global definitions of vision impairment. Until now, cataract surgery was believed to be one of the most cost-effective interventions globally. Data estimates from this study suggest that intervention aimed at alleviating URE is 40 times more cost-effective than cataract surgery. Given that URE is the leading cause of vision impairment, the utility values reported here will assist and improve current vision and eye health care prioritisation. These measures provide a basis to more accurately estimate the relative impact and economic consequences of this condition, determine how this compares to other conditions (medical and ocular) and determine the most cost-effective ways to alleviate the unnecessary blindness and impaired vision that results from avoidable causes.

According to the American Diabetes Association (ADA), over 21 million individuals in the United States have diabetes mellitus. Of those affected by the disease, most (between 90-95%) have the type 2 variety. It is estimated that nearly three-fourths of individuals with diabetes also suffer from hypertension. Hypertension is an insidious disease that can have devastating long-term consequences. Hypertension in patients with diabetes contributes to approximately 75% of all diabetes-related complications. Thus, the comorbidities of type 2 diabetes and hypertension are identified as being responsible for a myriad of vascular problems in affected patients. According to both the JNC 7 Report and the ADA guidelines, patients with diabetes and hypertension have demonstrated observable clinical benefit from use of the following antihypertensive drug classes: diuretics, beta-blockers, ACE Inhibitors, angiotensin-receptor blockers, and calcium-channel blockers. However, despite identification of the negative relationship between arterial hypertension/type 2 diabetes and vascular complications, uncertainty remains as to which pharmacological treatment would best prevent the frequent and costly complications in patients with these comorbidities. A Markov model utilizing both 1 st and 2 nd order Monte Carlo simulation was created to simulate the effects of each recommended drug class on the complications of stroke, myocardial infarction, the microvascular complication of nephropathy, and patient mortality. The present research was conducted with the belief that appropriate selection of an antihypertensive agent for the treatment of high blood pressure in patients with type 2 diabetes will minimize the occurrence of important cardiovascular and microvascular complications, thereby reducing the economic toll and increasing the life expectancy of patients plagued by these two disease states. The findings of the present work illustrate the cost and effectiveness of each therapeutic class of agents advocated for use in patients with type 2 diabetes and hypertension. Furthermore, the value of ACE Inhibitors compared to the other four drug classes espoused for use in this patient population clearly emerged. Ideally, the results of the current work will have the added benefit of partially eliminating the subjective value judgments that clinicians are required to make when deciding which pharmacotherapeutic alternative to initiate in a patient with both clinical conditions.