The temporary slowdown in large-scale surface warming during the early 2000s has been attributed to both external and internal sources of climate variability. Using semiempirical estimates of the internal low-frequency variability component in Northern Hemisphere, Atlantic, and Pacific surface temperatures in concert with statistical hindcast experiments, we investigate whether the slowdown and its recent recovery were predictable. We conclude that the internal variability of the North Pacific, which played a critical role in the slowdown, does not appear to have been predictable using statistical forecast methods. An additional minor contribution from the North Atlantic, by contrast, appears to exhibit some predictability. While our analyses focus on combining semiempirical estimates of internal climatic variability with statistical hindcast experiments, possible implications for initialized model predictions are also discussed.

Litopenaeus vannamei or Pacific white shrimp is the most widely farmed crustacean in the world. Shrimp are commonly fed feed containing 30-40% soybean meal or other plant-based feeds that are more economically and environmentally sustainable than animal-based feed. However, plant-based pellets are less palatable and less chemically attractive compared to animal material. Based on that, current research and practice includes the addition of specific marine animal meals in order to enhance palatability and attractability of plant-based shrimp feed. Yet, it is not sustainable or economically achievable to continue relying on marine animal meal. In the herein study, the effect of proprietary chemical mixtures designed by our research group as feed additives was examined based on their attractability and palatability in comparison to krill meal, a highly attractive and palatable supplement for shrimp feed. In palatability assays, total amount of pellets was measured before and after one-hour and three-hour periods of feeding in group-housed animals. In attractability assays, responses of shrimp were measured based on the number of probes and grabs on the source (airstone) of the stimulus being released. Each diet-set used contained different concentrations of krill meal and synthetic chemical mixtures. Results demonstrated these chemical mixtures enhance attractability and palatability of soybean based feed in L. vannamei when compared to krill meal. Furthermore, the addition of a proprietary mixture (= “premix”) improved responses in the attractability assays when compared to stimuli that did not contain the premix. Overall, results support the hypothesis that synthetic chemical mixtures can improve palatability and attractability of soybean meal based shrimp feed. This work could provide a reference for the development of synthetic chemoattractants and chemopallatants for the aquaculture of shrimp.

Thesis (MSc)--Stellenbosch University, 2013. / No abstract available.

This dissertation has two objectives: one, to dispel the “myth” and assumption that China holds on to an “absolute” view of sovereignty, and has arguably acted in accordance to this view; and two, to forward an alternative view of sovereignty as seen through Beijing’s eyes. This dissertation argues that China’s sovereignty is one which flexibly accommodates, at times voluntarily concedes, different mix of de facto rights according to each respective context and issue. This is attributed to China’s historical experiences with the concept, as well as its discourses. When “sovereignty” was introduced into Chinese thinking, the result is a “view” of sovereignty which juxtaposed Chinese previous understanding of “supreme authority” with an interpretation of the Western concept of sovereignty. “Sovereignty,” in this view, is essentially a de jure construct as its de facto component (or “right of governance”) is purposely and effectively detached from the concept to serve the political needs of the regime. It thus approximates one grounded on graded rings of sovereignty, where authority emanates from the core, but each “level of sovereignty” is entrusted to exercise different “right of governance.” As long as no overt challenge is posed to the idea that a single, de jure sovereignty— more specifically understood as a nominal “supreme authority”—resides in Beijing, this Chinese view of sovereignty is upheld. A “light” constructivist approach which explores the relationship between norms, ideational structures, agency and “discursive formations” is applied to the case studies of Hong Kong (and Macao) and Taiwan to support the arguments in this dissertation. Chinese discourses on “sovereignty” were examined in details through analysing a large sample size of Chinese academic writings from 1980 till 2008, in addition to policy documents and announced official positions of the Chinese leadership. This is further augmented by analyses of Beijing’s policy behaviours towards, in particular, Hong Kong’s autonomy and Taiwan’s international space.

This thesis engages in the debates on Japan’s foreign policy objectives and direction in the post-Cold War era by examining the case of Japan’s Myanmar policy with a particular focus on the question as to why Japan maintained its engagement policy line, although shifting to a more critical one, toward the Myanmar military government which was established in 1988. This thesis employs the analytical framework of neoclassical realism, recognizing international structure as the primary determinant of a state’s foreign policy while at the same time shedding light on domestic level factors, namely policy-makers’ perceptions, the government’s resource mobilization and the domestic policy-making system as intervening variables that incorporate international structural incentives into a state’s actual conduct of foreign policy. In conclusion, the empirical study reveals that Japan adhered to an engagement policy primarily because of Japanese policy-makers’ perceptions that it was the most practical and effective policy to promote Myanmar’s political and economic development, which would eventually contribute to regional stability and progress. This indicates a persistent feature of Japan’s foreign policy which can be described as ‘problem-driven pragmatism’, or Japan’s behavioural pattern of taking actions in response to concrete problems and pursuing practical problem-solving for bringing about incremental and pragmatic improvements in the problems by making necessary compromises with structural pressures and existing systems. This thesis makes a distinctive contribution from three aspects: providing new empirical evidence which fills the gap in conventional debates on Japan’s Myanmar policy objectives; proposing ‘problem-driven pragmatism’ as a new model of Japan’s foreign policy which addresses the shortcomings of existing arguments; and, affirming the applicability and efficacy of neoclassical realism for foreign policy analysis with the implication that it is necessary to examine multiple foreign policy agendas and multi-dimensional international structure in comprehending the critical tradeoffs that a state often faces.

published_or_final_version / Business Administration / Master / Master of Business Administration

Expanding groundfish production on the West Coast and in the United States in total, over the past decade, has increased competition in the groundfish market. During the same period, regulations have evolved to control production in the groundfish industry for the purpose of conserving the resource. Other regulations exist to control certain aspects of the market for groundfish. Such regulations are generally expected to have local impacts. However, little consideration is usually given to the impact regulations may have outside a local area. Indeed, since market competition has increased so significantly in this industry, the geographical distribution area has expanded considerably in recent years. Inter-regional impacts should be considered when regulations are established. The purpose of this research was to examine the impact selected regulations may have on markets for groundfish. The hypothesis tested by this research is stated as the following: regulations intended to impact local regions have no more than a local affect. Stated another way, regulatory authorities at state or regional levels generally intend to impose regulations that do not impact regions other than those under their jurisdiction. The test, then, is to determine if other regions are affected by "localized" regulations. The regulations to be examined include restriction or alteration of production in a limited region and established intra-state transportation rates (for seafood) that limit competition in the state transportation market. Specifically, alternative distribution patterns were generated in response to postulated changes in: (1) the availability of groundfish in the Oregon region and (2) California intra-state transportation rates to reflect more competition in the seafood transportation market (lower rates). The hypothesis was tested by estimating demand equations for groundfish, employing these in a spatial equilibrium model, and subjecting the results to a sensitivity analysis. The hypothesis testing consists of four parts, each independently insufficient to reject the hypothesis. As a whole, however, the four parts should provide enough evidence (although not a statistical test) to reject the hypothesis. The results of the research indicate rejection of the hypothesis was acceptable. Indeed, several of the regions where no affect was expected in response to the postulated changes showed significant impacts. This research was a pioneering attempt. The results are not conclusive, in part because of the absence of appropriate data. However, the results were significant enough to indicate promising possibilities for future research. In fact, a major contribution of the work was to point out how this research technique can be improved by refining inputs to the model and increasing its complexity to reflect more of the available routes associated with different product forms, product transport techniques and different species. The major result of the research was to indicate the need to consider impacts which extend beyond the local market in establishing regulations. / Graduation date: 1986

Pacific whiting and its by-products were good raw materials for high quality fish sauce production. Heat stable and salt activated enzymes were responsible for autolytic activity in Pacific whiting and by-products. According to temperature profiles of raw materials at various salt concentrations, two fermentation temperatures, 35°C and 50°C, were selected and compared at 25% salt under static atmospheric condition. Higher yields and faster production rate were obtained from samples incubated at 50°C. Therefore, the apparent optimum condition for fish sauce fermentation using Pacific whiting and its by-products was at 50°C with 25% salt under static atmospheric condition. All physicochemical characteristics, except color and browning color, reached the level of commercial fish sauce within 20 days. Nitrogen contents in all samples reached the level of commercial fish sauce (16.3 g-N/mL) within 112 days. Predominant microorganisms found during fermentation were Staphylococcus, Bacillus and Micrococcus. Alpha-amino acid content appeared to be identified as a good parameter to estimate total nitrogen content during fermentation (adjusted R²=0.84). Soluble solid was a good index for protein degradation in fermentation (adjusted R²=0.71). Proteolytic activity in Pacific whiting and its by-products were investigated using hemoglobin as substrate. Specific substrates and specific inhibitors were also used to classify the types of enzymes responsible for protein degradation in fish sauce fermentation. Serine proteases, cathepsin L-like enzymes and metalloproteases were active at 50°C in whole fish. However, trypsin-like enzymes, and cathepsin L-like enzymes were responsible for protein degradation in by-products at 50°C. At 35°, whole fish was degraded by serine proteases, cathepsin B-like enzymes, trypsin-like enzymes, and metalloproteases. Cysteine proteases were mainly responsible for the degradation of proteins in by-products, and serine proteases and trypsin-like enzymes had a minor role in hydrolyzing of by-products during fermentation. / Graduation date: 2000

Surimi is a seafood product which is used to manufacture restructured products such as artificial crab and lobster. Surimi is produced from fish fillets by washing to remove sarcoplasmic proteins and increase the concentration of myofibrillar proteins, and mixing with cryoprotectants. A valuable attribute of surimi is its ability to form an elastic gel, the gel network being formed by the myofibrillar proteins of fish muscle. It is generally accepted that the quality of surimi gels is influenced by the activity of endogenous protease which acts on the myofibrillar proteins. The proteases in Pacific whiting surimi (Merluccius productus) are particularly problematic due to their high catalytic activity on muscle myosin. The addition of whey protein concentrate (WPC) to Pacific whiting surimi has been shown to enhance the gel strength of the corresponding products produced from this surimi. The mechanism through which WPC enhances the gel strength of Pacific whiting surimi has not been determined, but it has been suggested that WPC acts to inhibit surimi autoproteolysis. The objective of this study was to determine whether the incorporation of WPC into Pacific whiting surimi inhibits autoproteolysis and/or protects the myosin fraction from proteolytic degradation. The effect of supplementing surimi with WPC, beef plasma protein (BPP) and bovine serum albumin (BSA) on its apparent autoproteolysis activity was determined. Three WPC preparations were tested, WPC 34, 34% protein; WPC 80, 80% protein; and WPC 95, 95% protein. Each of the additives was incorporated at the 1, 2, 3 or 4% level. Proteolysis of surimi and supplemented surimi samples was allowed to occur at 55°C. Proteolytic reaction mixtures were terminated by the addition of trichloroacetic acid (TCA). Proteolytic activity was estimated by measuring the difference in TCA-soluble peptides present in reaction mixtures of paired (identical) samples, one having been incubated at 55°C while the paired sample was kept on ice. Peptides were quantified by the bicinchoninic acid, Lowry, dye-binding and trinitrobenzenesulfonic acid methods. Results based on the different peptide assays were compared in order to asses the reliance of results on specific assay methods. BPP was found to have the most inhibitory activity in the autoproteolysis assays, followed by the WPC preparations and then BSA. Autoproteolysis was completely inhibited by the incorporation of 1% BPP, 3% WPC 80 and 2% WPC 95. The extent of inhibition by the WPC preparations was related to their protein content, the higher the protein content the greater the extent of inhibition per unit weight added to surimi. BSA was not an inhibitor of autoproteolysis under the conditions used in this study. The relative extents of inhibition observed for the different additives were independent of the method used to quantify the soluble peptide products. Each of the additives was also tested for their ability to protect the myosin component of surimi from proteolytic degradation. These experiments were done as described above for the autoproteolysis assays with the exception that following the incubation period a portion of the sample, either surimi or a surimi/additive mixture, was completely solubilized in detergent solution, subjected to SDS-PAGE electrophoresis and visualized by protein staining. In these experiments the additives were incorporated at the 4% level. No apparent degradation of myosin could be detected over a 60 min reaction period for surimi samples that were supplemented with BPP, WPC 80 and WPC 95. In contrast, surimi samples incubated without additive clearly showed a loss of myosin after 15 min reaction period. Some myosin degradation was apparent following the 60 min incubation period for the WPC 34-supplemented surimi. A further experiment was conducted to determine the mechanism through which WPC protects myosin and inhibits autoproteolysis. In this experiment WPC 95 and BPP were separately incubated at 55°C with a crude fish protease preparation, i.e. the reaction mixture approximates that used in the autoproteolysis assays except that it contains no surimi. The results indicate that BPP and WPC 95 behave in a similar manner. However, the results were inconclusive with regard to explaining the additive's mechanism of action. Plausible mechanisms which are consistent with the results are discussed. / Graduation date: 1994

Environment, safety and health (ESH) research has a strong tradition of conducting research in manufacturing to improve workplace ESH conditions and has tied its management strategy and technical practices to many significant priorities: illness and injury prevention, environmental sustainability, corporate social responsibility, compliance with regulatory and insurance requirements, and dealing with NGO (non-governmental organization) pressures. ESH research rarely examines ESH management strategy in the broader context of business/operations. This oversight makes it difficult to make accurate recommendations for practice and regulation because ESH researchers and business/operations researchers tend to function as if the other does not exist with the very great possibility that key relationships remain undiscovered. In this study, case study methods were used with five manufacturing facilities in the Pacific Northwest to evaluate the usefulness of the Development Levels Rating System (DLRS). Data were collected using interviews, site tours, and publicly available records. Within case and cross-case analysis were used to analyze the data. Consistent patterns were found in how the facilities structured, organized, and financed the ESH function. Moreover, important insights were found regarding the facilities' levels of ESH management strategy and their levels of risk. The results support the DLRS model as being useful in assessing ESH management strategy in relation to a facility's level of risk. Moreover, several new pathways were uncovered including: the significance of multi-stakeholder approaches in EHS and operations research; the importance of joint management strategies; and the faulty nature of compliance-based ESH management strategies. Future research should be considered to test the DLRS tool using focus groups and quantitative methods. This study was approved by the Institutional Review Board (IRB). / Graduation date: 2012