Extended performance solar electric propulsion thrust system study. Volume 1: Executive summary

Several thrust system design concepts were evaluated and compared using the specifications of the most advanced 30 cm engineering model thruster as the technology base. The extensions in thruster performance required for the Halley's comet mission were defined and alternative thrust system concepts were designed. Confirmation testing and analysis of thruster and power-processing components were performed, and the feasibility of satisfying extended performance requirements was verified. A baseline design was selected from the alternatives considered, and the design analysis and documentation were refined. A program development plan was formulated that outlines the work structure considered necessary for developing, qualifying, and fabricating the flight hardware for the baseline thrust system within the time frame of a project to rendezvous with Halley's comet. An assessment was made of the costs and risks associated with a baseline thrust system as provided to the mission project under this plan. Critical procurements and interfaces were identified and defined. Results are presented

Participatory GIS for growth management in the Cheat Lake planning district of Monongalia County, West Virginia

Participatory Geographic Information Systems (PGIS) can be an effective methodology for collecting public input in local land use planning and smart growth management. PGIS-based approaches provide residents with an opportunity to discuss and map their priority land use issues and to identify land use hotspots in a way that is not typically possible in a general public meeting. This thesis research explores how community qualitative information about land use can be incorporated into a PGIS for the Cheat Lake Planning District of Monongalia County, West Virginia. The research presented in this thesis demonstrates how qualitative information strengthens land use planning and improves communication about smart growth management options at the local level. Multimedia information, such as community narratives, mental maps, and geo-referenced photographs are collected using qualitative research methods and combined with existing geo-spatial information in order to shape future political discussions about land use planning in the case study area

Epidemiological models of rabies in domestic dogs: dynamics and control

Epidemiological models are frequently used to estimate basic parameters, evaluate alternative control strategies, and set levels for control measures such as vaccination, culling, or quarantine. However, inferences drawn from these models are sensitive to the assumptions upon which they are based. While many simple models provide qualitative insights into disease dynamics and control, they may not fully capture the mechanisms driving transmission dynamics and, therefore, may not be reasonable approximations of reality. This thesis examines how the predictions made by simple models are influenced by assumptions regarding the dispersion of the transition periods, alternative infection states, and transmission heterogeneity resulting from population structuring. More realistic models of rabies transmission dynamics among domestic dogs in Serengeti District (Tanzania) are developed and applied to the problem of assessing vaccination efficacy, and designing pulsed vaccination campaigns. Several themes emerge from the discussion of the models. First, the characteristics of outbreaks can be strongly influenced by the dispersion of the incubation and infectious period distributions, which has important implications for parameter estimation, such as the estimation of the basic reproductive number, R0. Similarly, alternative infection states, such as long incubation times, can substantially alter outbreak characteristics. Second, we find that simple SEIR models fail to accurately capture important aspects of rabies disease outbreaks among domestic dog populations in northern Tanzania, and therefore may be a poor basis for assigning control targets in this system. More complex models that included the role of human intervention in limiting outbreak severity, or that included population structure, were able to reproduce the observed outbreak size distribution. We argue that there is greater support for the structured population model, and discuss the implications of the three models on the evaluation of vaccination efficacy. Third, at a more regional scale, we build metapopulation models of rabies transmission among domestic dog sub-populations. We use a Bayesian framework to evaluate competing hypotheses about mechanisms driving transmission, and sources of reinfection external to the dog population. The distance between sub-populations, and the size of the sub-populations receiving and transmitting infection are identified as important components of transmission dynamics. We also find evidence for a relatively high rate of re-infection of these populations from neighbouring inhabited districts, or from other species distributed throughout the study area, rather than from adjacent wildlife protected areas. We use the highest ranked models to quantify the efficacy of vaccination campaigns that took place between 2002-2007. This work demonstrates how a coarse, proximate sentinel of rabies infection is useful for making inferences about spatial disease dynamics and the efficacy of control measures. Finally, we use these metapopulation models to evaluate alternative strategies of pulse vaccination in order to maximize the reduction in the occurrence of rabies. The strategies vary in both the way in which vaccine doses are allocated to sub-populations, and in the trade-off between the frequency and intensity of vaccination pulses. The most effective allocation strategy was based on a measure of the importance of sub-populations to disease dynamics, and it had 30-50% higher efficacy than the other strategies investigated. This work demonstrates the strong potential for the role of metapopulation models in optimizing disease control strategies

Alien Registration- Hawthorne, Mildred L. (Blaine, Aroostook County)

https://digitalmaine.com/alien_docs/22637/thumbnail.jp

The relation between cholesterol and haemorrhagic or ischaemic stroke in the Renfrew/Paisley study

Studies have found little association between cholesterol and overall stroke risk, but this could be attributable to different relations for haemorrhagic and ischaemic stroke. Stroke mortality data from prospective studies cannot usually be divided into stroke subtypes. We have therefore analysed stroke based on hospital admissions, obtained by computerised linkage with acute hospital discharges in Scotland for a large prospective cohort study

Cementitious grouts for intermediate level nuclear waste (ILW) encapsulation - effect of compositional changes upon hydration

Grouts containing high levels of replacement by BFS are the preferred route to disposal for a large majority of ILW in the UK. A number of techniques, SEM image analysis, chemical shrinkage, ICC, TGA and XRD, have been applied to assess the rate and degree of hydration of such cementitious grouts. This study forms a base for quantifying the effects of modifications to the physical and chemical composition of both the OPC and the BFS components of the matrix in order to identify the sensitivity or otherwise of the technique to ensure that a continuity of supply is maintained

Where should livestock graze? Integrated modeling and optimization to guide grazing management in the Cañete basin, Peru

Integrated watershed management allows decision-makers to balance competing objectives, for example agricultural production and protection of water resources. Here, we developed a spatially-explicit approach to support such management in the Cañete watershed, Peru. We modeled the effect of grazing management on three services – livestock production, erosion control, and baseflow provision – and used an optimization routine to simulate landscapes providing the highest level of services. Over the entire watershed, there was a trade-off between livestock productivity and hydrologic services and we identified locations that minimized this trade-off for a given set of preferences. Given the knowledge gaps in ecohydrology and practical constraints not represented in the optimizer, we assessed the robustness of spatial recommendations, i.e. revealing areas most often selected by the optimizer. We conclude with a discussion of the practical decisions involved in using optimization frameworks to inform watershed management programs, and the research needs to better inform the design of such programs

Frontiers of change and governance in contractual agreements: The possible role of exploitation - Uniting Reformed Church De Doorns v President of the Republic of South Africa 2013 5 SA 205 (WCC)

In the South African common law of contract there appears to be support for the open norm of public policy as a general clause to ameliorate the effects of unfair contracts and terms which are contrary to public policy. The courts have on several occasions held that contracts or terms would be regarded as contrary to public policy had they come about where the  parties were in an unequal bargaining relationship and this inequality was linked with another factor(s). In this case note it is argued that the  element of unequal bargaining position may be contrary to public policy if it is linked with exploitation as the other factor. The element of exploitation was highlighted in the recent court decision of Uniting Reformed Church, De Doorns v President of the Republic of South Africa 2013 5 SA 205 (WCC). In this case the applicant church owned three properties on which were  three schools under the control of the State. The church and the State had concluded 20-year notarial leases in respect of each of the properties. A term in the contract provided that after the expiration of the lease period the church would transfer the properties to the State free of charge. After the expiration of the leases the State demanded the transfer of the  properties. The church disputed the claim, averring that the term was unenforceable because the parties had been in an unequal bargaining position and that the enforcement of the term constituted expropriation in contravention of the property clause of the Constitution. It is submitted that expropriation without compensation is not only contrary to section 25 of the Constitution but constitutes exploitation. It is suggested that where exploitation results from an unequal bargaining relationship it provides the "further factor" that, together with the inequality in bargaining power, is sufficient to establish that the term or contract is in conflict with public  policy. This contributes to giving meaning to the term "public policy". To support this argument, reference is made to the German Civil Code, the Swiss Civil Code, consumer protection legislation and the philosophy of Wertheimer.   

Structural insights into functional amyloid inhibition in Gram –ve bacteria

Amyloids are proteinaceous aggregates known for their role in debilitating degenerative diseases involving protein dysfunction. Many forms of functional amyloid are also produced in nature and often these systems require careful control of their assembly to avoid the potentially toxic effects. The best-characterised functional amyloid system is the bacterial curli system. Three natural inhibitors of bacterial curli amyloid have been identified and recently characterised structurally. Here, we compare common structural features of CsgC, CsgE and CsgH and discuss the potential implications for general inhibition of amyloid