The objective of this project was to evaluate methods to remediate a wood I-joist with a single, circular hole in the web while leaving utilities in place. The methods were experimentally evaluated with a full-scale bending test using four equally spaced point loads. There were three depths of joists with varying flange widths and two span lengths (4.88 m & 2.44 m). Failure modes for the long span joists without holes were in the flanges in either tension, compression or lateral buckling; but once a hole was introduced the majority were classified as shear failures. Effectiveness of the remediation was evaluated based on three criteria: strength, stiffness, and ease of installation/cost. The OSB collar patch was effective for 8 out of the 12 series tested. A maximum reduction of load from a joist with no hole to one with a hole was 49% for the long span and 58% for the short span. The OSB collar was not as effective in returning stiffness to the joists, but was easier to install and less expensive than the LSL patch. / Graduation date: 2013

Graduation date: 1999

This dissertation traces the historical transformation of the Canada-UK commodity chain for wheat-bread as a lens on processes of local and global change in agrofood relations. During the 1990s, the Canadian Wheat Board (Canada’s monopoly wheat seller) and Warburtons, a British bakery, pioneered an innovative identity-preserved sourcing relationship that ties contracted prairie farmers to consumers of premium bread in the UK. Emblematic of the increasing importance of quality claims, traceability, and private standards in the reorganization of agrifood supply chains, I argue that the changes of the 1990s cannot be understood outside of historical legacies giving shape to unique institutions for regulating agrofood relations on the Canadian prairies and in the UK food sector. I trace the rise, fall, and re-invention of the Canada-UK commodity chain across successive food regimes, examining the changing significance of wheat- bread, inter-state relations between Canada, the UK, and the US, and public and private forms of agrofood regulation over time. In particular, I focus on the way in which changing food regime relations transformed the CWB, understood as the nexus of institutions tying prairie farmers into global circuits of accumulation. When in the 1990s, the CWB and Warburtons responded to structural crises in their respective industries by re-inventing the Canada-UK wheat trade, the result was significant organizational and industry change. On the prairies, the CWB has shown how – contrary to expectations -- centralized marketing and quality control may help prairie farmers adapt to the demands of end-users in the emerging ‘economy of qualities’. In the UK, Warburtons has led the ‘premiumisation’ of the bread sector, traditionally defined by consumer taste for cheap bread, over the last 15 years. The significance of the shift towards quality chains in the wheat-bread sector is analyzed in light of conflicts over the proposed introduction of genetically engineered (GE) wheat to the Canadian prairies.

This research project examines the degree of transparency of the Canadian Federal Government’s decision-making processes and institutions with respect to the human consumption of animals produced through modern biotechnology (biotechnology-produced animals). It provides a timely study of the Federal Government’s decision-making process; as of January 2013 the government has yet to determine whether, and how, biotechnology-produced animals are to be approved for human consumption. Foods that contain genetically modified organisms (GMOs) are already commercially widely available in Canada. Research is well underway to see if biotechnology-produced animals may also be developed and introduced into the food system. Government decisions regarding the human consumption of biotechnology-produced animals have the potential to revolutionize food systems globally and nationally. This thesis offers an analysis of primary and secondary data focusing on the degree of federal transparency with respect to regulating GMO foods generally and, more specifically, the emerging policy issues around biotechnology-produced animals. This exploration sets the stage for the following investigation of barriers as well as opportunities to fostering federal transparency with respect to policy and regulatory decisions regarding GMO foods. Findings are directed towards members of the communities of interest who are interested in questions relating to the degree of federal transparency and government approaches to foods that contain material produced through modern biotechnology.

This dissertation traces the historical transformation of the Canada-UK commodity chain for wheat-bread as a lens on processes of local and global change in agrofood relations. During the 1990s, the Canadian Wheat Board (Canada’s monopoly wheat seller) and Warburtons, a British bakery, pioneered an innovative identity-preserved sourcing relationship that ties contracted prairie farmers to consumers of premium bread in the UK. Emblematic of the increasing importance of quality claims, traceability, and private standards in the reorganization of agrifood supply chains, I argue that the changes of the 1990s cannot be understood outside of historical legacies giving shape to unique institutions for regulating agrofood relations on the Canadian prairies and in the UK food sector. I trace the rise, fall, and re-invention of the Canada-UK commodity chain across successive food regimes, examining the changing significance of wheat- bread, inter-state relations between Canada, the UK, and the US, and public and private forms of agrofood regulation over time. In particular, I focus on the way in which changing food regime relations transformed the CWB, understood as the nexus of institutions tying prairie farmers into global circuits of accumulation. When in the 1990s, the CWB and Warburtons responded to structural crises in their respective industries by re-inventing the Canada-UK wheat trade, the result was significant organizational and industry change. On the prairies, the CWB has shown how – contrary to expectations -- centralized marketing and quality control may help prairie farmers adapt to the demands of end-users in the emerging ‘economy of qualities’. In the UK, Warburtons has led the ‘premiumisation’ of the bread sector, traditionally defined by consumer taste for cheap bread, over the last 15 years. The significance of the shift towards quality chains in the wheat-bread sector is analyzed in light of conflicts over the proposed introduction of genetically engineered (GE) wheat to the Canadian prairies.

A series of pilot-scale granular media filtration experiments was conducted to examine the effect of media roughness on filter performance and to evaluate the applicability of spherical, rough engineered ceramic filter media for use in granular media filters used for drinking water treatment. Filter media performance was assessed using turbidity and particle count reductions, Cryptosporidium oocyst and oocyst-sized microsphere removal, head loss and stability of operation. Experiments were designed to allow related facets of current filtration research to be examined. These included: effect of loading rate, coagulant type and dosage, and suitability of latex microspheres as surrogates for Cryptosporidium oocyst removal by granular media filtration. This study indicated that increased filter media roughness consistently improved turbidity and particle count reduction under the conditions investigated. As well, the engineered media also consistently achieved greater stability of operation during non-ideal operational periods (e.g. sudden change in filter influent turbidity).Oocyst removals were generally improved by media roughness, though this improvement was reliant on operating conditions, such as coagulant dose and type of coagulant used. The surrogate relationship between oocyst-sized latex microspheres and oocyst removal by filtration was also dependent on coagulant dose and type of coagulant. During trials with no coagulant addition, contrasts in oocyst removal were not significant, suggesting that neither surface roughness nor the size of media used were significant factors impacting oocyst removal by filtration during those periods of impaired operation. When pre-treating raw water with PACl, the engineered ceramic media achieved up to 1.25 log10 higher oocyst removals than conventional media. This improvement in oocyst removal relative to conventional media was not observed when alum was used as the primary coagulant, however. Future studies should directly compare engineered and conventional media filtration performance, using other raw water sources and different operating conditions. Biologically active filtration should also be included in future performance studies because the rough, highly porous surface of the engineered ceramic media is likely to provide excellent biofilm support.

A series of pilot-scale granular media filtration experiments was conducted to examine the effect of media roughness on filter performance and to evaluate the applicability of spherical, rough engineered ceramic filter media for use in granular media filters used for drinking water treatment. Filter media performance was assessed using turbidity and particle count reductions, Cryptosporidium oocyst and oocyst-sized microsphere removal, head loss and stability of operation. Experiments were designed to allow related facets of current filtration research to be examined. These included: effect of loading rate, coagulant type and dosage, and suitability of latex microspheres as surrogates for Cryptosporidium oocyst removal by granular media filtration. This study indicated that increased filter media roughness consistently improved turbidity and particle count reduction under the conditions investigated. As well, the engineered media also consistently achieved greater stability of operation during non-ideal operational periods (e.g. sudden change in filter influent turbidity).Oocyst removals were generally improved by media roughness, though this improvement was reliant on operating conditions, such as coagulant dose and type of coagulant used. The surrogate relationship between oocyst-sized latex microspheres and oocyst removal by filtration was also dependent on coagulant dose and type of coagulant. During trials with no coagulant addition, contrasts in oocyst removal were not significant, suggesting that neither surface roughness nor the size of media used were significant factors impacting oocyst removal by filtration during those periods of impaired operation. When pre-treating raw water with PACl, the engineered ceramic media achieved up to 1.25 log10 higher oocyst removals than conventional media. This improvement in oocyst removal relative to conventional media was not observed when alum was used as the primary coagulant, however. Future studies should directly compare engineered and conventional media filtration performance, using other raw water sources and different operating conditions. Biologically active filtration should also be included in future performance studies because the rough, highly porous surface of the engineered ceramic media is likely to provide excellent biofilm support.

<p>Engineered nanoparticles (ENPs) are a part of everyday life. They are incorporated into a wide array of products including sunscreens, clothing, electronics, paints, and automobiles. One particular type of ENP, quantum dots (QDs), are fluorescent semi&ndash;conducting nanocrystals, and are touted as the next generation of medical tracers and energy&ndash;efficient light bulbs. The continued development and expansion of commercial applications for QDs ensure that they will enter the aquatic environment following manufacture, use, and disposal. Unfortunately, very little information exists on the bioavailability and sub&ndash;lethal toxicological effects of QDs in aquatic organisms. The studies described in this dissertation focused on determining the toxicological effects of Lecithin&ndash;encapsulated CdSe/ZnS quantum dots in larval and adult <italic>Fundulus heteroclitus</italic> (the mummichog). </p> <p>Quantum dot dispersion is greatly influenced by environmental parameters such as pH, natural organic matter concentration, and ionic strength. Lecithin&ndash;encapsulated core&ndash;shell QDs aggregated and precipitated from suspension in 20 ppt seawater. QD aggregates adhered to the exterior chorion of <italic>Fundulus</italic> embryos in aqueous embryo exposures, but did not traverse the chorion and deposit into the body of the fry. Incidences of developmental abnormalities increased and hatching rates declined in embryos exposed to the highest concentration tested (100 &mu;g/ml). </p> <p>Dietary assessments showed that QDs were bioavailable to adult <italic>Fundulus</italic>. While QDs or their degradation products traversed the intestinal epithelial and were deposited to the liver, less than 0.01% of the cadmium from the QDs was retained in the liver and intestinal tissues. QD uptake did not cause significant changes in hepatic total glutathione or lipid peroxidation levels, nor did it statistically alter the expression of genes involved in metal metabolism and oxidative stress&mdash;metallothionein, glutathione&ndash;s&ndash;transferase, glutathione peroxidase, and superoxide dismutases. There was, however, a clear gender&ndash;specific trend in the level of Cu/Zn&ndash;superoxide dismutase transcription. In addition, QDs did impact fecundity presumably by feminizing male fish. Vitellogenin transcription was elevated and relative gonad size reduced in male <italic>Fundulus</italic> consuming 10 &mu;g QD per day. Lastly, QDs or their degradation products were maternally transferred to the eggs following six to eight weeks of parental exposure, thus posing a risk to <italic>Fundulus</italic> progeny. Based on the results of these studies, it is apparent that chronic exposure to QDs could result in adverse affects in teleosts and other organisms inhabiting estuarine environments.</p> / Dissertation

Implantation of tissue engineered pancreatic constructs can provide for a physiologic regulation of blood glucose levels. A major concern in designing such constructs is ensuring sufficient oxygenation of the cells, as oxygen is usually the limiting nutrient affecting cell viability and function. Furthermore, in vivo factors influencing construct oxygenation often lead to implant failure, and are detected primarily on end physiologic effects. The ability of perfluorocarbons (PFCs) to dissolve large amounts of oxygen and their high fluorine content makes these compounds a potentially valuable oxygen delivery tool and good 19F Nuclear Magnetic Resonance (NMR) markers for dissolved oxygen concentration (DO). Experimental studies and simulations showed that although the addition of 10 vol% PFC increased construct oxygenation, this improvement was minimal and had limited benefits on the growth and function of encapsulated bTC-tet cells under normoxic and hypoxic conditions. A dual PFC method that utilizes 19F NMR spectroscopy was developed to noninvasively monitor DO within a tissue construct and in its surroundings. In vitro studies using an NMR-compatible bioreactor demonstrated the feasibility of this method to monitor the DO within alginate beads containing metabolically active bTC-tet cells, relative to the DO in the culture medium, under perfusion and static conditions. In vivo, the method was capable of acquiring real-time DO measurements in murine models. Measured DO can be correlated with the physiological state of the implant examined post-explantation and was compatible with the therapeutic function of the implant.

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 66-69). Also available on the World Wide Web.