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Successful establishment of riparian vegetation on riverbanks and bedforms depends on river hydrology and related flow and sediment erosion processes. Extreme flow-induced erosion events can uproot vegetation, leading in some cases to failure of bank protection and river restoration schemes. This thesis uses experimental, analytical, and numerical approaches to examine key aspects of the mechanisms of vegetation uprooting by flow. First, the ability of riparian vegetation to respond to different water table regimes is investigated in terms of root growth and resistance. To this purpose, small-scale Salix cuttings were allowed to grow under different water level regimes. At the end of the growing period, extracted samples, obtained through pullout tests, were analysed in terms of root biomass distribution and resistance to external forces. The results demonstrate the driving influence of water and oxygen availability on the vertical configuration of below-ground biomass and thence on uprooting resistance. Second, a free-body model is derived to predict the critical rooting length - a key parameter that determines the probability of flow-induced uprooting of flexible plants at different erosion stages. Model validation is achieved using laboratory and field-scale data. Third, the dynamics of mobilization of stranded living wood logs from alluvial bedforms is investigated experimentally. Pullout test results are used to assess the root resistance of small-scale wood logs at several stages of growth. Trends in below- and above-ground biomass, together with the free-body model, enable detection of 'biological time windows' within which re-mobilization becomes possible. The results illustrate that uprooting occurs within two time-lapses, which coincide with particular growth stages of the plant. Finally, a combined analytical and numerical model is derived. This model uses the probability of flow-induced plant uprooting as a proxy to study how perturbations to the natural flow regime may drive riparian ecosystem dynamics towards new and potentially irreversible statistical equilibrium states. The model is applied to an actual case study, in which dam impoundment of a reach of the Maggia River, Switzerland, has led to intense riparian vegetation encroachment with consequent river narrowing. The output of the model sheds light on the type of irreversibility that may arise in riverine ecosystems of severely impounded river basins. The theoretical and experimental results presented in the thesis should be useful to river engineers and managers responsible for river restoration projects, natural flood management schemes, and optimal dam regulation strategies.

This dissertation uses tools from economics to study three different aspects of educational markets in the developing world. In chapter 1, I analyze how competition among private schools in Pakistan affects student outcomes when (1) the match between a school and a student matters for learning, and (2) poorer students may be less informed about their match when they make enrollment decisions. I find that greater competition may lead schools to compete more intensively for wealthier, better-informed students, lowering learning for poorer students in the average private school and increasing learning for wealthier students. In chapter 2, I examine how cultural norms that encourage children to care for their parents when they reach adulthood affect human capital investment in children in Ghana, Indonesia, Rwanda, and Mexico. I find that children targeted by these norms receive more educational investments. Finally, in chapter 3, I study the labor market for public school teachers in Pakistan by analyzing the effect of a policy shock that changed both teacher salaries and accountability on student learning. I find that simultaneously lowering teacher salaries and increasing accountability lowered the cost of providing education and improved students’ learning., Public Policy

Improving our understanding of the anatomy of spinal locomotor networks, how they physiologically interact with proprioception to execute locomotion in vivo, and how ES combined with physical training mechanistically reorganizes spinal networks will provide crucial information in how to use ES optimally to improve clinical outcomes along with inspiring future design of epidural electrodes and training programs. This thesis aims to adapt an engineering and big data workflow to answer these pressing biological problems, namely finding a way to generate large sets of data from current immunohistochemistry (IHC) techniques known to generate very little and to find a way to analyze this large amount of data in a time efficient manner when the current gold standard has been manual analysis.

In communication for social change, a catalyst (individual or organisation) plays an important role in creating dialogue within the community, leading to collective action and providing solutions for common problems. In urban communities of developing countries, this role is more essential because of the complexities in population and social issues. This research aimed to evaluate the impact of such a catalyst on urban community development in Ho Chi Minh city [HCMC], one of the largest cities in East Asia (World Bank, 2015) through the case study of LIN Center for Community Development (LIN is an acronym for „Listen, Inspire, Nurture‟). LIN‟s activities focus on enabling local non-profit organisations [NPOs] through different programmes, all of which engage a participatory communication approach. In evaluating LIN‟s work, this research project employed the „Integrated model for measuring social change processes and their outcomes‟ by Figueroa, Kincaid, Rani & Lewis (2002). Data was collected through ethnographic non-participant observation, in-depth semi-structured interviews and secondary data. This research shows that LIN is considered as a catalyst in the community development of HCMC. Due to LIN‟s work, NPOs have altered their self-perception from being „charity organisations‟, to being a part of the community development process in HCMC. NPOs are more confident in their own capacities and have more stable financial support. NPOs have also started collaborating with the corporate sector and the public. In the meantime, the corporate sector (skilled volunteers and donors) have developed a better understanding of the non-profit sector and have made stronger contributions to the development of NPOs in HCMC. Throughout the whole process, LIN applies the participatory communication approach through interpersonal communication, encouraging the dialogue among LIN‟s stakeholders in most of its activities. LIN also provides robust information to the community though social media, mass media and public events. However, LIN‟s catalyst role still faces challenges, particularly in applying Western concepts in the Vietnamese context. Firstly, LIN does not emphasise the importance of a leader‟s role for LIN staff and NPOs and the environment lacks understanding of what it means to be an independent leader due to the Marxist-Leninist foundations and Confucianism influence underlying Vietnamese society and politics. Secondly, LIN assumes that all NPOs understand the Western community development terms LIN brings to Vietnam (community fund, non-profit organisation and skilled volunteering), while there are still NPOs that do not understand these concepts correctly. Thirdly, due to barriers of power-distance in an Asian society such as Vietnam, it is difficult for all NPOs to achieve an equitable dialogue when working together. As a result, this research will contribute an emerging catalyst model for urban community development in Vietnam, which is suggested through three crucial elements: l) a leadership strategy for a catalyst and NPOs; 2) context understanding (local context and stakeholders‟ characteristics) and; 3) an impact evaluation framework based on the local context. These elements need to be taken into consideration in both interpersonal communication and media activities. When these elements are executed carefully, activities organised by the catalyst will be more effective, leading to the stakeholders‟ individual changes, who then become catalysts for their own communities and provide positive social change impact.

Abstract: As the developing world industrializes, humanity needs to produce a greater fraction of its energy via renewable resources in order to alleviate the scarcity of fossil fuels as well as environmental damage from the exhaust of these fuels. However, renewable sources of energy tend to be intermittent in nature and therefore require a method to store generated energy for use at a later time. Hydrogen gas is a promising potential fuel because it can be produced from water with oxygen gas as a byproduct, resulting in an environmentally-friendly production-consumption cycle with water as the product upon combustion. This thesis presents two different approaches to hydrogen generation from water – using light and electricity – with earth-abundant metal oxide catalysts. A dual-semiconductor photocatalyst consisting of α-Fe2O3 and CuFe2O4 semiconductor materials in close contact was prepared by first templating iron oxide precursors on sugarcane leaf followed by functionalization of the resulting α-Fe2O3 surface with copper nanoparticles and high-temperature annealing. Nanoparticle catalysts were further loaded onto the surface of the combined α-Fe2O3/CuFe2O4 heterostructure. Investigation of the CuFe2O4 material revealed that it was a poor semiconductor that could evolve hydrogen independently but at low rates. A novel nickel-iron oxide phase with rock-salt structure was synthesized via thermal decomposition of mixed nickel and iron oleate complexes. Despite the natural instability of bivalent iron in rock-salt crystal structures, the single-crystal [Ni,Fe]O nanoparticles were stable even under ambient conditions for long periods of time, even upon thermal treatment at 200 °C. Shape control of the nanoparticles could be achieved via modification of the synthetic conditions, resulting in a variety of shapes including cubes, stars, and spheres. The composition of the nanoparticles could also be controlled yielding a wide composition range of nickel iron oxide rock-salt nanocrystals. The surface of the nanoparticles was determined to contain trivalent iron and an amorphous structure unique from the bulk. The nickel-iron oxide nanoparticles were applied for water oxidation after integration onto tin-doped indium oxide and fluorine-doped tin oxide electrode surfaces. The functionalization was accomplished using UV light irradiation, which resulted in the formation of durable nanoparticle films that withstood the stresses of water oxidation. Electrochemical studies suggested that catalytic activity arose from the surface of the nanoparticles, suggesting that the [Ni,Fe]O phase did not participate in water oxidation. Nonetheless, by giving rise to the catalytic surface layer, [Ni,Fe]O was found to be important for water oxidation as activity was reduced when the phase was lost via heating.

Finite volume (FV) numerical solvers to the two-dimensional shallow water equations are the foundation of the current state-of-the-practice, industry-standard flood models. The second-order Discontinuous Galerkin (DG2) alternative show a promising way to improve current FV-based flood model formulations, but is yet under-studied and rarely utilised to support flood modelling applications. This is contributed by the mathematical complexity constructed within the DG2 formulation that could lead to large computational costs and compromise its stability and robustness when used for practical modelling. Therefore, this PhD research aims to develop a new flood model based on simplified DG2 solver that is improved for flood modelling practices. To achieve this aim, three objectives have been formed and addressed through analyses involving academic and experimental test cases, as well as test cases that are recommended by the UK Environment Agency to validate 2D flood model capabilities, whilst benchmarking the simplified DG2 solver against four FV-based industrial models. Key research findings indicate that the simplified DG2 solver can equally retain conservative properties and provide second-order accurate predictions as the standard DG2 solver whilst offering around 2.6 times runtime speed up. Additionally, the simplified DG2 solver can be reliably efficient to provide predictions close to the outputs of the industrial models, in simulating flood scenarios covering large catchment-scale areas and at a grid resolution greater or equal than 5 m, particularly when the local limiting is disabled. However, the local limiting is still needed by the simplified DG2 solver when modelling detailed velocity fields at sub-metre grid resolutions, particularly in regions of highly active wave-structure interactions as commonly encountered in urban flooding around steep-sloped building structures.

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The beef industry in South Dakota is an important component of the state's agricultural economy. South Dakota beef producers market approximately 2.0 million head of cattle and calves annually with value in excess of 1.2 billion dollars in 1984. This revenue represents over 60 percent of total livestock receipts for the state and over 35 percent of total agricultural sales. In 1985, South Dakota cattle gross income was over $1,336 million. The significance of South Dakota cattle production is further demonstrated by a national ranking of fifth in beef cows that calved and ninth in total production of cattle and calves in 1985. Cattle numbers are declining both on a national and state level, declining from a national total of 114.4 million head at the end of 1980 to 105.5 million head at the end of 1985. South Dakota cattle numbers declined from 4.1 million head to 3.6 million head over the same five year period. Consumption of beef per capita has held fairly constant since 1978 at 77-80 retail pounds and is presently around 77 pounds per capita. Even with the declining numbers of cattle and consumption remaining constant, price has not increased enough to stop the reduction phase of the present cycle. In fiscal year 1985, 1,499,489 head of cattle were shipped out of South Dakota with only 477,167 head of cattle coming in, leaving a net out flow of 1,022,322 head. State inventories were down slightly. This leaves the South Dakota cattle producer dependent on out-of-state cattle demands to absorb the net flow of cattle out of South Dakota. The total number of packing plants in the United States decreased from a peak in 1976 of 6,255 plants to 5,558 at the end of 1983. Average plant size is increasing, reflecting closings of small plants through the last decade. U.S. beef slaughter is shifting west and south. The West North Central and Southern Plains regions reported a 12 percent increase in the proportion of cattle slaughtered there between 1972 and 1982. This indicates a shirt in slaughter away from plants located near large urban areas in East North Central and Eastern regions of the nation to plants located close to cattle production areas. This shift in slaughter plant location parallels the westward movement of cattle feeding. Today, plants are increasing the production of boxed beef and decreasing the production of whole carcass beef. Processing beef into boxed beef increased from 44 percent to 58 percent of all steer and heifer slaughter between 1979 and 1982. This study was conducted to update existing information on the South Dakota cattle industry at the producer, feeder, slaughter, and processor levels and to examine construction and operating costs of South Dakota beef slaughter plants.

Farm leasing arrangements are important in eastern South Dakota. In 1954, 48 percent of all farm land in that area was farmed by tenants. In the entire state, 46 percent of all agricultural land was rented and 68 percent of the operators leased all or part of the land they operated. Between 1880 and 1940 the trend in farm tenancy was steadily increasing. While there has been a decline in the percentage of tenancy since 1940, this appears to be due to the very favorable period of production and prices. Because of the present price-cost squeeze, the percentage of tenants may soon be increasing. Federal legislation has largely concentrated on helping farm families achieve ownership and much of the research that has been done is concerned with land credit, supervised loans, and contract buying. While owner-operatorship may well be a desirable goal, the large proportion of tenancy suggests that more attention directed toward improvement of leasing arrangements might be desirable. Obviously there are many facets to leasing that could be explored and improved upon; but basically, the problem for the tenant is one of security of possession on the land which he operates. Short-term leases do not give the tenant enough security to make it possible for him to farm like an owner would. The tenant does not know that he will be able to remain on the farm long enough to reap the benefits of a soil improvement program and he is reluctant to invest his time and money in repairing buildings and fences. The one-year crop share lease is most commonly used in South Dakota. Landlords feel that a one-year lease is necessary to keep a share tenant on his toes and to make sure he does a good job of farming. Surveys conducted in 1950 and 1952 revealed that 83 percent of the landlords used one-year leases, but that 66 percent of the tenants preferred leases for a three-year term or longer. Since landlords say they cannot rent for periods longer than one year under crop share arrangements, the problem then becomes one of seeking alternative leases that are adaptable to agreements for periods of three years or longer. Cash leases or flexible cash leases are more suitable to long term agreements since the rent to be paid is clearly specified in the lease and cannot be affected by the managerial ability of either the landlord or the tenant after the lease is signed. The value of the produce delivered to the landlord under share rents depends to a considerable extent on the tenant’s ability as a farmer. Hence, share rent landlords tend to discriminate against beginning farmers who have not had a chance to prove their managerial ability. When the landlord’s income depends upon the quantity of crops produced, he is reluctant to rent to a beginning farmer. Thus, landlords with the better farms tend to get the older, more experienced farmer while the beginning farmer frequently has to settle for an inferior or inadequate unit. Both the tenant’s lack of experience and the inadequate unit tends to increase his insecurity. More objective fixed produce or cash leases would provide greater security for such tenants since their management would not affect the landlord’s rent. The increased security might allow many beginning farmers to expand their livestock and machinery inventory more rapidly and allow them a better level of living than is possible under uncertain share crop tenure or when a tenant is forced to buy in order to have security. Because objective leases tend to reduce landlord-tenant disagreement and lease terminations, they help lend stability to the population of a community. When people have secure tenure, they can take a more active part in rural organizations such as churches, schools, and local government. Hurlburt found that under cash leases people in selected areas of South Dakota, Iowa, and Minnesota remained on the same farm longer than they did under any other type lease even though the cash leases were frequently made for one year at a time. Such results seem reasonable because the landlord and tenant do not have as many things about which to disagree when cash rentals are paid. Obviously tenants cannot rent for cash if landlords prefer to use a crop share lease. While there has been some work done to determine what kind of lease the landlords prefer, little has been done to determine what the tenants desire. There is some evidence that many tenants want longer term leases and greater security. But little or nothing has been done to determine how much more rent, if any, tenants would be willing to pay in return for greater security of tenure. In undertaking this study, it seemed logical to first determine the strength of tenants’ preference for longer term leases by asking them how much they would be willing to pay for various alternatives. If their responses indicate that landowners could make long-term cash agreements that would yield net returns of 6 to 8 percent, with less risk than crop-share leases afford, then there is a possibility of attracting new capital into farm lands on a cash rental basis.