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>Magister Scientiae - MSc / Antimicrobials are chemical compounds that destroy or inhibit the growth of microorganisms. The majority of these antimicrobials are actually natural products or natural product derived with key examples being the pioneer antibiotics penicillin and cephalosporin. Antimicrobials are an extremely important class of therapeutic agents; however, the development of drug resistance and slow pace of new antibiotic discovery is one of the major health issues facing the world today. There is therefore a crucial need to discover and develop new antibacterial agents. In this study, the potential of marine algae as a source of new antibiotics was explored. Crude organic extracts and chromatographic fractions obtained from small-scale extraction of 17 different marine algae were used to prepare a pre-fractionated library that would be tested against several disease causing microorganisms. The activity of the pre-fractionated library and purified compounds was determined against a panel of drug resistant microorganisms namely Acinetobacter baumannii ATCCBAA®-1605™, Enterococcus faecalis ATCC® 51299™, Escherichia coli ATCC® 25922™, Staphylococcus aureus subsp. aureus ATCC® 33591™ and Candida albicans ATCC® 24433™. Finally, cytotoxicity tests of 50 selected library extracts and isolated compounds were done against two cell lines namely MCF-7 (breast cancer) and HEK-293 (kidney embryonic).

Thesis (M.Dev.) --University of Limpopo, 2013 / Small-scale farmers in the land reform programme are faced with many challenges which affect their operations adversely that they cannot maintain a sustainable farming momentum and grow into competitive farming enterprises. Instead they are failing and recently some are already selling the land back. Some of the challenges facing them include lack of access to the markets, lack of finance, poor business planning and lack of business know-how. This study assesses the business management competencies among the small-scale farmers on the land reform programme. The central desire of this study is to establish whether or not small scale farmers have the necessary business management competencies to drive and grow their farms into competitive commercial farms that can contribute to employment creation, rural poverty alleviation, rural food security and economic growth. Outcomes from this study reflect that small-scale farmers do not have capacity on the critical functional areas of business management and as a result their business operations are on the brink of collapsing, and thus directly failing the intentions of land reform programme. With all other factors held constant, this study has revealed that business management competency is a huge vacuum amongst the small-scale farmers, and if business oriented training is not prioritized as a post-settlement support, the land reform’s small-scale farming performance is heading towards a complete collapse.

Thesis (M.Dev.) --University of Limpopo, 2011 / Agricultural development programs under the former apartheid homeland system which was dissolved in 1994 could not successfully achieve their objectives. The current democratic government reviewed the policies and programs put in place during apartheid era which eventually led to the implementation of the Revitalisation of Smallholder irrigation Schemes (RESIS) in line with the Reconstruction and Development Program (RDP) and Growth, Employment and Redistribution (GEAR) programs. It was anticipated that RESIS would among others improve agricultural productivity, play a role in local economic development, improve food security, provide improved benefits and the livelihoods of the rural communities where the schemes are situated. The aim of the study is to assess whether the RESIS program has had an impact so as to make recommendations for future similar programs. The objective of the study is to assess the impact of RESIS program on the livelihoods of the participants and to shed light on whether such programs can be used for poverty reduction, which is a key objective in the programs of LDA. Tšwelopele irrigation scheme in Greater Tubatse Municipality within Sekhukhune District Municipality was selected as the area at which the study was conducted. A random sample of 50 beneficiaries was selected from a total of 75 RESIS beneficiaries and divided into two strata, namely, full-time farmers (both male and female) and part-time farmers (male and female) farmers. Interviews were conducted through completion of questionnaires responded to by the selected participants and key informants in the scheme. Qualitative and quantitative methods were used to obtain the responses from the scheme participants and the data processed using SPSS. Based on the analysis of respondents‟ perceptions of the farmers, the study concludes that RESIS is perceived to have had a positive impact on the livelihoods of the beneficiaries. Gross margin analysis supports the farmers‟ perceptions.

With an ever increasing concern for the environment, different methods of managing organic waste on dairy farms have been explored and analyzed. Anaerobic digestion has long been a popular method of managing organic waste. Its popularity stems from the potential to decrease greenhouse gases, improve air quality and provide a source of additional revenue for the farm. Problems with implementing anaerobic digestion arise from high failure rates, high start-up costs and continuous maintenance and equipment replacement. Subsidies for the initial investment and improved technology have increased the possibility of large-scale dairy farms to adopt anaerobic digestion. Due to economies of scale large-scale dairy farms are more able to adopt anaerobic digestion, but small-scale dairies struggle to finance the investment, maintain the digester system and provide sufficient organic waste to continuously feed the microorganisms inside the digester system. The increasing impact of urbanization greatly impacts the demand for anaerobic digestion on small-scale farms to mitigate the negative effects of organic waste produced by dairy farms. Dr. Conly Hansen at Utah State University suggested we use an IBR digester model to analyze the feasibility of adopting anaerobic digestion on small-scale farms. The IBR digester system is more conducive to small-scale dairies located in regions with varying temperature (i.e., Utah), and may be the solution to mitigate the negative effects of organic farm waste. Dr. Donald McMahon also suggested we analyze the potential of implementing a digester on a dairy farm that produces artisan cheese. We predicted that this would improve the feasibility due to the need to dispose of whey from the cheese production. To determine the feasibility of implementing a digester system on a small-scale dairy farm the net present value and the internal rate of return were calculated to estimate the success of the investment. These financial measures were calculated from equipment price quotes, estimations from the literature review and from using estimated annual receipts and costs for a dairy farm, artisan cheese plant and anaerobic digester system. The feasibility also depends on the success of marketing the products produced from the digester system and the farmer’s participation in incentive programs for digester systems. The products produced vary from electricity to waste disposal services, and marketing an array of diverse products and services is important to the success of the digester system. The feasibility determined by this study was estimated using generalized assumptions from various sources and should be analyzed by individual operations to determine specific farm feasibility.

How to solve a multivariate quadratic polynomial equation system is believed to be one of the key points to beark AES. But to solve the MQE problem is NP-hard, so it's very important to develop a good algorithm to solve it. In such a situation, the XL algorithm is claimed to be the method to solve the MQE problem, and the cryptographers pay a lot of attetion to it. But the XL algorithm works only when the equation system is overdefined, for this reason cryptographers are looking for some ways, such as BES, to increase the numbers of equations. In practice we know that the process of solving MQE, the system will extend very fast, therefore if we input too many equations and variates, we usually using out of memory before finding out the solution. In the paper we use multiple plaintext-ciphertext to increase the number of equations and try to do some pre-computing work to reduce the size of a problem, and make it work better in pratice.

Thesis (M.A.) - Simon Fraser University, 2005. / Theses (Dept. of Geography) / Simon Fraser University. Also issued in digital format and available on the World Wide Web.

The number of farmers markets in the United States increased from 3,706 in 2004 to 8,268 in 2014 (Agriculture Marketing Service, 2014). Often times, small-scale agricultural producers do not harvest enough goods to be sold in large grocery store corporations and thus have turned to farmers' markets, roadside stands, you-pick operations, and community supported agriculture (CSA) shares as pathways for reaching customers directly (Chase & Winn, 1981; Payne, 2002). The purpose of this study was to explore and describe how such small-scale producers who participate in farmers' markets gain and develop business-related information and business skills. A single case study design developed and applied to explore the entrepreneurial learning environment relevant to small-scale agricultural producers in Cochise County, Arizona. The current study is framed conceptually by Politis's (2005) entrepreneurial learning model. The data was collected through semi-structured interviews, observations, and relevant documents. Data was organized and analyzed both ideographically and nomothetically. The findings indicate that some small-scale agricultural producers who reside in Cochise County, Arizona participate in Southern Arizona farmers' markets for economic viability and/or lifestyle reasons. The producers who participate in Southern Arizona farmers' markets as their sole means of generating income and/or to continue to be able to afford their engagement in agricultural activities were categorized under the economic viability theme. Those producers who participate in Southern Arizona farmers' market primarily to socialize and to exchange knowledge with community members and other farmers or ranchers were categorized under the lifestyle theme. The data also revealed that the participants engaged in entrepreneurial learning primarily within informal settings and through corresponding channels. While, informal learning is likely to remain the primary method of knowledge sharing across the small-scale agricultural producer community in Cochise County, Arizona. However, by providing such producers with greater opportunities to develop deeper and more robust knowledge and skills specific to entrepreneurship and small business development and management through non-formal learning opportunities (e.g., innovative Extension program), the number of producers with enhanced training capacities and cutting edge knowledge will increase across Cochise County.

Recurrent crises due to overexploitation of fishery resources have been among the biggest natural resource management failures of the 20th century. This problem has both biological and socio-political elements and understanding of human dimensions represents a key step toward the formulation of sound management guidelines for natural resources. One of the strategies proposed to understand human dimensions is through the use of local knowledge. Integrating local peoples' knowledge with scientific research and data analysis, could aid in the design of fisheries management strategies in a cost-effective and participatory way.I introduce an approach to incorporating fishers' local knowledge at a large, regional scale. I focused on the spatial and temporal distribution of fishing activities from 17 communities in the Northern Gulf of California, Mexico. Participatory mapping (maps produced by local fishers) through a rapid appraisal (survey methodology) were used to identify the spatial and temporal dimensions of fishing activities. A geographic information system was used to generate 764 map layers used for a preliminary analysis of rapid-appraisal spatial data. Post-survey workshops with fishers were organized to facilitate an internal validation of spatial information using geographic information system software. We characterized the information based on fishing communities, fishing methods, target species and spawning sites. We also applied spatial analysis techniques to understand the relative importance and use of fishing grounds, fishing seasons and the influence that fishing communities have over the region. This dissertation addressed the problem of integrating the human dimensions of small-scale fisheries using geospatial tools and local knowledge (LK) - data collection, integration, internal validation, analysis and access - into a multidisciplinary research to support decision making in natural resource planning for small-scale fisheries management and conservation in the Northern Gulf of California, Mexico.

The independent operators (IOs) are small forest operators with timber allocation volumes in Saskatchewan under 20,000 m³. Due to their scale, this group is characterized by above- average industry wood procurement and transaction costs. In the past, IO’s above average costs were compensated by above average market prices for the products they produce and limited competition. In recent years, increased competition confounded by low demand and low prices, as well as rapidly increasing operating costs have made it necessary for IOs to restructure operations to reduce costs and increase competitiveness. This thesis investigates the benefits of restructuring IOs using a cooperative business model to help reduce costs, eliminate competitive inefficiencies within the industry, and create economies of scope in IO fibre procurement activities and fibre utilization. Within the literature review, numerous cooperative models used in the forest and agriculture industries and the advantages and disadvantages associated with each cooperative type are explored. Next, the potential economic benefits of restructuring IOs under the new generation cooperative model are examined using a comparative economic analysis of the business as usual fibre procurement cost model and IO NGC fibre procurement cost model derived within this study. Data obtained from an IO case study and interviews with IO industry representatives is fitted to the models to generate fibre procurement cost data for each model. The resulting fibre procurement cost values for each model are then compared and further examined using sensitivity and breakeven analysis. The results of this analysis reveal that the new generation cooperative model has the potential to provide significant economic benefits to IOs through the creation of economies of scope in harvesting costs, but has little effect on the six other costs that make are included in fibre procurement costs. The analysis also reveals that so long as the NGC consist of IOs that require both large and small diameter fibre, the IO NGC has the potential to provide significant economies of scope in fibre utilization.