Improving water efficiency is and will continue to be a top concern to meet the world food production demands for a growing population. By having a clear understanding of water efficiencies, communities will be able to address these concerns from an economic standpoint and use more productive methods to grow food and limit water consumption. This study examines the water efficiencies of three irrigation methods over a single growing season in southeastern Oklahoma. Two crops, tomatoes and cucumbers, were grown using drip irrigation, a self-wicking container, and a non-circulating hydroponics barrel. Results at the end of the season showed the drip irrigation method had the highest water efficiency in terms of yield of product over water applied for both crops. The drip irrigation method also had the lowest associated set up costs and second lowest time requirements after the hydroponics method. These results were found to be consistent with other studies that compared drip irrigation to other irrigation methods and showed drip to have the highest water efficiencies.

In order to meet emissions targets under the UN Paris Agreement, every nation must decarbonize its energy production. The US isn't reducing energy-related emissions fast enough to meet its targets for keeping overall warming under 2°C above pre-industrial levels. This constitutes a grave injustice to the most vulnerable populations of the world, who are suffering the ill effects of climate change already. The challenge of eliminating fossil fuels from the US energy system is not simply one of technological limitations, however. The aim of this dissertation is to provide an analysis of historical, political, and, most importantly, conceptual barriers to decarbonization of energy in the US. I believe not just our policies and our markets, but our thinking has to change if we are to avoid recapitulating the injustices of the fossil fuel energy system. I argue that energy policy in the US over time has ossified around a narrow conception of energy as fossil energy—as a substance, rather than as a service. I call this the fossil conception of energy (FCE). I follow historical traces of the FCE in three key areas: political discourse in the US, the relationships between the US dollar and OPEC oil (a complex web …

The Romans were known for taking technology and advancements from other peoples they encountered and making them their own. This pattern holds true in military affairs; indeed, little of the Roman military was indigenously developed. This dissertation looks at the origins of the Roman's mainline weapons systems from the beginning of Roman Republic expansion in the fourth century BC to the abandonment of Western-style armaments in favor of Eastern style ones beginning in the late-third century AD. This dissertation determines that the Romans during that time relied predominately on the Celtic peoples of Europe for the majority of their military equipment. One arrives at this conclusion by examining at the origins of the major weapons groups: armor, shields, spears, swords, and missile weapons. This determination is based on the use of ancient written sources, artistic sources, and archaeological sources. It also uses the large body of modern scholarship on the individual weapons. The goal is to produce a unified work that addresses the origins of all weapons in order to see if there is an overarching impact on the Roman military from outside cultures. When one studies whence the weapons that ended up in Romans hands originated, a decided Celtic …

The physical characteristics (i.e., nanostructure and stiffness) of the extracellular matrix where cells reside have been shown to profoundly affect numerous cellular events in vivo and also been employed to modulate cell behavior in vitro, yet how these physical cues regulate cell behavior is still elusive. Therefore, we engineered a variety of nanotopographies with different shapes and dimensions, and investigated how the nanotopographical cue, through focal adhesions-cytoskeleton-nucleus pathway, affected cell phenotype and function. We further designed and fabricated well-defined substrates which had either identical biochemical cue (adhesive ligand presentation) but different nanotopographical cues or identical nanotopography but different biochemical cues, and dissected the roles of these cues in cell modulation. In addition, we revealed that the human mesenchymal stem cells (hMSCs) could obtain nanotopographical memory from the past culture environment, and the nanotopographical memory influenced the future fate decision of the hMSCs. Moreover, we evaluated the effects of substrate nanotopographical and stiffness cues on the fibrogenesis of human lung fibroblasts in response to carbon nanotubes and highlighted the significance of these physical cues in the development of physiologically relevant in vitro models for nanotoxicological study. The mechanistic understanding of the physical regulation of cell behaviors will provide important insight into …

In 1873, a financial crisis plunged the United States into a deep economic depression that exacerbated a number of post-war economic issues. By the late 1870s, political dissent centered primarily on financial issues merged into the Greenback movement, which represented a loose coalition of reformers calling for economic relief based on the expanded use of greenbacks (paper currency issued by the United States Treasury during the Civil War). The Greenback Party emerged as a direct response to federal financial policies, but in Texas, it also provided a broad political platform for those opposed to the policies of "Redeemer/Bourbon" Democrats. The Greenback Party of Texas brought together a wide range of dissenters, including disgruntled Democrats, ousted Republicans, and many different economic and social reformers. From 1876, when the first Greenback clubs appeared in Texas, to the Greenback Party's virtual disappearance after the election of 1884, the Texas Greenbackers reached across boundaries of section, race, class, and sometimes gender; brought together farmers, workers, and professionals; Southerners and Northerners, white and black; former Confederates and former Unionists; native-born Americans and immigrants; and received sizable support from multiple counties in the northern, eastern, and central part of the state. In spite of its short …