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Endocrine Disruption of Levonorgestrel in Early-life Stages of Fathead Minnows, Pimephales Promelas

Description: Pharmaceuticals have routinely been detected in the environment resulting in a growing concern about whether these drugs could elicit effects on aquatic organisms. The concerns are centered on the highly conserved nature of mammalian therapeutic targets in fish. These pharmaceuticals are found at very low levels in the environment, which can result in sub-lethal effects in aquatic organisms. Therefore, 28 d early-life stage studies were conducted on six pharmaceuticals to assess their impacts on survival and growth fathead minnow larvae. Two pharmaceuticals tested, carbamazepine and fenofibrate, resulted in no alterations to survival and growth. However, amiodarone, clozapine, dexamethasone, and levonorgestrel (LNG) reduced survival at concentrations tested with LNG being the most potent at 462 ng/L. Survival was increased with amiodarone and clozapine; however LNG significantly decreased growth at 86 ng/L. Therefore, the most potent pharmaceutical tested was the synthetic progestin LNG with survival and growth impacts at concentrations less than 1 μg/L. Further analysis was conducted by measuring specific endocrine related mRNA transcript profiles in FHM larvae following the 28 d ELS exposure to LNG. Transcripts of 3β-HSD, 20β-HSD, and FSH were significantly down-regulated following 28 d exposure to both 16.3 and 86.9 ng/L LNG. Also, CYP19a expression was significantly down-regulated at 86.9 and 2392 ng/L LNG. Subsequently, a second study examined time periods that may be most sensitive (e.g., windows of sensitivity) for FHM larvae exposed to LNG. Larvae were exposed to a single concentration of LNG (i.e. LOECgrowth of 86.2 ng/L as determined in the 28 d ELS study) for different time periods starting with fertilized egg through 28 dph. Growth and mRNA expression of the four differentially expressed transcripts from the first study were measured. Regardless of the duration of exposure, LNG significantly decreased growth in fathead minnow larvae at day 28. For both 20β-HSD and CYP19a, ...
Date: August 2013
Creator: Overturf, Matthew D.

Endogenous Constructivist Implications for Methodology : Focus on Young Children with Developmental Delay in the Social and Emotional Domains

Description: The Ecologically-Based Activity Plan (EBAP) is proposed as a method to create a transition between special education and general education. It serves as a tool to help classroom teachers assess the environment of the class and as a method for embedding instruction within the naturally occurring context of the endogenous constructivist classroom. In this study the EBAP was used to reduce aggressive behavior and increase prosocial behavior among five children who displayed developmental delays in the social and emotional domains.
Date: December 1998
Creator: McCrary, Donna E. (Donna Evelyn)

Endogenous Information and Inter-state War Expansion

Description: Scholars have long debated the causes of late third party state joining in ongoing inter-state wars. This research has generally concluding that peace-time conditions, measured in terms of: third party capabilities; proximity to warring states; and inter-state alliances, are determining factors in the decision to join. However, these studies utilize theories derived from static pre-war measures of capabilities and motivation to explain late joining; indeed, the same measures that fail to predict participation at war's outset. Further, extant research has no explanation for why weak and non-proximate states every participate. Existing theory thus fails to provide a comprehensive explanation of joining behavior. This project contends that a resolution lies the interaction between pre-war conditions and intra-war events. Intra-war events that are allowed to vary on a per battle basis, including change in combat location and alliance entry and exit from combat, reveal new information about the war and its progress, thereby forcing third party states to recalculate their initial decision to abstain in relation to their pre-existing situation. Incorporation of intra-war processes helps to better explain decisions by third party states to join ongoing inter-state wars late in their development, and why states that frequently choose to abstain (e.g., weak states) ever choose to participate. This project is executed using a combination of ex post facto historical case studies, a theory of joining based on pre and intra-war environments, and large-N empirical analysis on all inter-state wars 1823-1988, conducted utilizing a novel collection of event-level data based on inter-state war battles.
Date: December 2012
Creator: Liebel, Steven R.

Endogenous Nucleotide Pools in Growing Cells of Azotobacter Vinelandii

Description: The objective of this investigation was to examine the changes in the nucleotide pools of Azotobacter vinelandii during the growth cycle. Endogenous ribonucleotides were extracted from A. vinelandii using trichloroacetic acid (TCA; 12% w/v). The 5' mono-, di- and triphosphates of adenine, guanine, uracil and cytosine were separated and quantified by anion-exchange high performance liquid chromatography. Results indicated that the adenylate energy charge of A. vinelandii paralleled the growth rate during exponential phase and that it declined rapidly as the stationary phase was reached. In addition, the amount of each nucleotide in A. vinelandii tended to increase in the logarithmic phase and decrease in the stationary phase in a similar manner to the energy charge.
Date: August 1987
Creator: Lee, Yick-Shun

The Enemy of My Enemy: International Alliances Against Transnational Terrorist Organizations

Description: A dearth of pre-existing research in the field prompted this thesis on whether traditional econometric analyses of war deterrent alliances are applicable to modern alliances for counter terror purposes. Apparent foundational and contextual differences between the two types of alliances and the costs and benefits member nations derive from each lead the author to theorize that factors contributing to the formation of each alliance are fundamentally similar. Multiple types of statistical models are used to measure variables from the Correlates of War and Polity datasets combined with custom variables in a new dataset concerning major transnational terrorist attacks and the resultant alliances in testing the effect of traditionally contributing formation factors on alliances against terrorism. The results indicate that some contributing factors are similar, extant analysis tools have utility and that further investigation is justified.
Date: December 2010
Creator: Berthume, Joshua Guy

The Enemy of My Enemy Is What, Exactly? the British Flanders Expedition of 1793 and Coalition Diplomacy

Description: The British entered the War of the First Coalition against Revolutionary France in 1793 diplomatically isolated and militarily unprepared for a major war. Nonetheless, a French attack on the Dutch Republic in February 1793 forced the British to dispatch a small expeditionary force to defend their ally. Throughout the Flanders campaign of 1793, the British expeditionary force served London as a tool to end British isolation and enlist Austrian commitment to securing British war objectives. The 1793 Flanders campaign and the Allied war effort in general have received little attention from historians, and they generally receive dismissive condemnation in general histories of the French Revolutionary Wars. This thesis examines the British participation in the 1793 Flanders campaign a broader diplomatic context through the published correspondence of relevant Allied military and political leaders. Traditional accounts of this campaign present a narrative of defeat and condemn the Allies for their failure to achieve in 1793 the accomplishments of the sixth coalition twenty years later. Such a perspective obscures a clear understanding of the reasons for Allied actions. This thesis seeks to correct this distortion by critically analyzing the relationship between British diplomacy within the Coalition and operations in Flanders. Unable to achieve victory on their own strength, the British used their expeditionary force in Flanders as diplomatic leverage to impose their objectives on the other powers at war with France.
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Date: August 2012
Creator: Jarrett, Nathaniel W.

Energy and Archetype: A Jungian Analysis of The Four Zoas by William Blake

Description: The purpose of this study is to examine the parallels between the tenets of Carl Jung's psychology and the mythopoeic structure of Blake's poem, The Four Zoas. The investigation is divided into three chapters. The first deals with the major conceptual parallels between the intellectual systems of the two men. The second is a detailed analysis of the poem, and the third concludes the study by discussing the originality of Blake's thought. Blake anticipated much of Jung's psychology. The parallels between the two are so strong that each man seems to corroborate and validate the opinions and insights of the other. The extent to which he foreshadows Jung reveals Blake to be one of the most original thinkers of any period of time.
Date: August 1974
Creator: Hamilton, Lee T.

Energy-Aware Time Synchronization in Wireless Sensor Networks

Description: I present a time synchronization algorithm for wireless sensor networks that aims to conserve sensor battery power. The proposed method creates a hierarchical tree by flooding the sensor network from a designated source point. It then uses a hybrid algorithm derived from the timing-sync protocol for sensor networks (TSPN) and the reference broadcast synchronization method (RBS) to periodically synchronize sensor clocks by minimizing energy consumption. In multi-hop ad-hoc networks, a depleted sensor will drop information from all other sensors that route data through it, decreasing the physical area being monitored by the network. The proposed method uses several techniques and thresholds to maintain network connectivity. A new root sensor is chosen when the current one's battery power decreases to a designated value. I implement this new synchronization technique using Matlab and show that it can provide significant power savings over both TPSN and RBS.
Date: December 2006
Creator: Saravanos, Yanos

Energy Distribution of Sputtered Neutral Atoms from a Multilayer Target

Description: Energy distribution measurements of sputtered neutral particles contribute to the general knowledge of sputtering, a common technique for surface analysis. In this work emphasis was placed on the measurement of energy distribution of sputtered neutral atoms from different depths. The liquid Ga-In eutectic alloy as a sample target for this study was ideal due to an extreme concentration ratio gradient between the top two monolayers. In pursuing this study, the method of sputter-initiated resonance ionization spectroscopy (SIRIS) was utilized. SIRIS employs a pulsed ion beam to initiate sputtering and tunable dye lasers for resonance ionization. Observation of the energy distribution was achieved with a position-sensitive detector. The principle behind the detector's energy resolution is time of flight (TOF) spectroscopy. For this specific detector, programmed time intervals between the sputtering pulse at the target and the ionizing laser pulse provided information leading to the energy distribution of the secondary neutral particles. This experiment contributes data for energy distributions of sputtered neutral particles to the experimental database, required by theoretical models and computer simulations for the sputtering phenomenon.
Date: August 2000
Creator: Bigelow, Alan W.

Energy for a Sustainable Future

Description: This report provides a high-level overview and specific recommendations for governments to help achieve universal energy access and reduce energy intensity. The report recommends that energy access be achieved through a combination of grid extension, mini-grid access, and off-grid access approaches. The need for government targets, access to financing, capacity building, and improved utility performance are also discussed.
Date: April 2010
Creator: UN Secretary-General’s Advisory Group on Energy and Climate Change (AGECC)

Energy Harvesting Wireless Piezoelectric Resonant Force Sensor

Description: The piezoelectric energy harvester has become a new powering option for some low-power electronic devices such as MEMS (Micro Electrical Mechanical System) sensors. Piezoelectric materials can collect the ambient vibrations energy and convert it to electrical energy. This thesis is intended to demonstrate the behavior of a piezoelectric energy harvester system at elevated temperature from room temperature up to 82°C, and compares the system’s performance using different piezoelectric materials. The systems are structured with a Lead Magnesium Niobate-Lead Titanate (PMN-PT) single crystal patch bonded to an aluminum cantilever beam, Lead Indium Niobate-Lead Magnesium Niobate-Lead Titanate (PIN-PMN-PT) single crystal patch bonded to an aluminum cantilever beam and a bimorph cantilever beam which is made of Lead Zirconate Titanate (PZT). The results of this experimental study show the effects of the temperature on the operation frequency and output power of the piezoelectric energy harvesting system. The harvested electrical energy has been stored in storage circuits including a battery. Then, the stored energy has been used to power up the other part of the system, a wireless resonator force sensor, which uses frequency conversion techniques to convert the sensor’s ultrasonic signal to a microwave signal in order to transmit the signal wirelessly.
Date: December 2013
Creator: Ahmadi, Mehdi

Energy Losses of Protons Projected through a Plasma Due to Collisions with Electrons of the Plasma for a Variety of Non-Maxwellian Electron Velocity Distributions

Description: The purpose of this thesis is to study energy losses suffered by protons in traversing a plasma through collision with the electrons of the plasma. For these electrons a variety of non-Maxwellian velocity distributions are assumed.
Date: August 1961
Creator: Kregel, Mark Douglas

Energy Paths and Political Commitments: Their Roles in Environmental Inequality

Description: Decentralized renewable energy procurement has gained traction in recent years for its potential to alleviate rural energy poverty and environmental degradation in developing countries. Hence, this study investigates if deploying renewable energy can mitigate rural energy poverty in developing countries as often claimed. Because any energy regime cannot be initiated or sustained without the conviction of local political leaders, the study also evaluates the extent to which government investments in the development of renewable energy technologies and the energy sector, affect the environmental quality (i.e. greenhouse gas emissions) of developing countries. Energetic theory and environmental inequality constitute the key conceptual premises guiding this study. Ordinary least squares regression is utilized to analyze the relationship between key variables. The results reveal that as of 2010, use of renewable energy can indeed support rural electrification. Higher GNI per capita and use of conventional fuels are also positively related to rural electrification, all else equal. As for environmental degradation in 2005 and 2008, R&D investments actually tend to increase GHG emissions; procuring energy from either renewable or non-renewable sources is however, found to be environmentally detrimental, net of all other variables. Finally, some evidence is found for the role of aid funds and multilateral debt in abating GHG emissions.
Date: May 2014
Creator: Ong, Corinne

Energy Policy Act

Description: The Energy Policy Act (EPA) addresses energy production in the United States, including: (1) energy efficiency; (2) renewable energy; (3) oil and gas; (4) coal; (5) Tribal energy; (6) nuclear matters and security; (7) vehicles and motor fuels, including ethanol; (8) hydrogen; (9) electricity; (10) energy tax incentives; (11) hydropower and geothermal energy; and (12) climate change technology. For example, the Act provides loan guarantees for entities that develop or use innovative technologies that avoid the by-production of greenhouse gases. Another provision of the Act increases the amount of biofuel that must be mixed with gasoline sold in the United States.
Date: January 4, 2005
Creator: United States. Congress

Energy Policy in the Republic of China and Japan, 1970-1985: A Comparative Examination of Energy Politics and Policies

Description: The impact of the energy crises in the 1970s hit all oil-importing countries much harder than it hit countries endowed with domestic supplies of energy. Energy politics and policies for the oil-importing countries have become vital issues that need to be examined. The purpose of this dissertation is to examine and compare the energy politics and policy processes in the Republic of China (ROC) and Japan during the period of 1970-1985. The study focuses on the politics of energy policies, using a policy analysis or systems framework for examining the policy processes in the two countries. A comparison is made of energy environments, the political actors, the institutions, and finally the substance of energy policy. An assessment is then made of the effects or consequences of energy policies on these two countries. In attempting to study energy politics and policies in these two Asian countries, the researcher began with a policy model or conceptual schema of energy politics from which the researcher raised a number of research questions. These questions were used to guide the direction of the study. A comparison was first made of energy systems, and then the major actors in the energy resources field were identified by comparing the political systems. Comparison of the political systems in energy politics helped to explain the differences in the political outcomes of energy policy. An assessment was made by using a series of multiple regression models to assess and compare the consequences of energy policies in these two countries. The final purpose of this dissertation is to develop a conceptual model or framework, for understanding the complexity, uncertainty, and interrelatedness of energy policies. The researcher concludes that comparative policy studies are useful and provide insights which otherwise would be missed.
Date: August 1987
Creator: Wang, Han-Kuo

Energy Usage While Maintaining Thermal Comfort : A Case Study of a UNT Dormitory

Description: Campus dormitories for the University of North Texas house over 5500 students per year; each one of them requires certain comfortable living conditions while they live there. There is an inherit amount of money required in order to achieve minimal comfort levels; the cost is mostly natural gas for water and room heating and electricity for cooling, lighting and peripherals. The US Department of Energy has developed several programs to aid in performing energy simulations to help those interested design more cost effective building designs. Energy-10 is such a program that allows users to conduct whole house evaluations by reviewing and altering a few parameters such as building materials, solar heating, energy efficient windows etc. The idea of this project was to recreate a campus dormitory and try to emulate existent energy consumption then try to find ways of lowering that usage while maintaining a high level of personal comfort.
Date: December 2011
Creator: Gambrell, Dusten

Engaging Lives: a Nomadic Inquiry Into the Spatial Assemblages and Ethico-aesthetic Practices of Three Makers

Description: This research is a nomadic inquiry into the ethics and aesthetics of three makers’ social and material practices. Deleuze’s concept of the nomad operated in multiple ways throughout the process, which was embedded in performative engagements that produced narratives of becoming. Over four months, I built relationships with three people as I learned about the ethico-aesthetic significance of their daily practices. The process started by interviewing participants in their homes and expanded over time to formal and informal engagements in school, community, and agricultural settings. I used Guattari’s ecosophical approach to consider how subjectivity was produced through spatial assemblages by spending time with participants, discussing material structures and objects, listening to personal histories, and collaboratively developing ideas. Participants included a builder who repurposed a missile base into a private residence and community gathering space, an elementary art teacher who practiced urban homesteading, and a young artist who developed an educational farm. The research considers the affective force of normalized social values, the production of desire by designer capitalism, and the mutation of life from neoliberal policies. Our experiences illuminate the community-building potential of direct encounters and direct exchanges. The project generates ideas for becoming an inquirer in the everyday and reveals possibilities for producing pedagogical experiences through collective and dissensual action. Ultimately, the project produces hope for performative and anti-disciplinary approaches to education, rupturing false divisions that fragment the force of thought, to produce, instead, aesthetic experiences that privilege processes and are based in direct and collective engagements with life.
Date: May 2014
Creator: Coats, Cala R.

Engineered Microbial Consortium for the Efficient Conversion of Biomass to Biofuels

Description: Current energy and environmental challenges are driving the use of cellulosic materials for biofuel production. A major obstacle in this pursuit is poor ethanol tolerance among cellulolytic Clostridium species. The first objective of this work was to establish a potential upper boundary of ethanol tolerance for the cellulosome itself. The hydrolytic function of crude cellulosome extracts from C. cellulolyticum on carboxymethyl cellulose (CMC) with 0, 5, 10, 15, 20 and 25% (v/v) ethanol was determined. Results indicated that the endoglucanase activity of the cellulosome incubated in 5% and 10% ethanol was significantly different from a control without ethanol addition. Furthermore a significant difference was observed in endoglucanase activity for cellulosome incubated in 5%, 10%, 15%, 20% and 25% ethanol in a standalone experiment. Endoglucanase activity continued to be observed for up to 25% ethanol, indicating that cellulosome function in ethanol will not be an impediment to future efforts towards engineering increasing production titers to levels at least as high as the current physiological limits of the most tolerant ethanologenic microbes. The second objective of this work was to study bioethanol production by a microbial co-culture involving Clostridium cellulolyticum and a recombinant Zymomonas mobilis engineered for the utilization of oligodextrans. The recombinant Z. mobilis ZM4 pAA1 and wild type ZM4 were first tested on RM medium (ATCC 1341) containing 2% cellobiose as the carbon source. Ethanol production from the recombinant Z. mobilis was three times that observed from the wild type Z. mobilis. Concomitant with ethanol production was the reduction in OD from 2.00 to 1.580, indicating the consumption of cellobiose. No such change in OD was observed from the wild type. The recombinant ZM4 was then co-cultured with C. cellulolyticum using cellobiose and microcrystalline cellulose respectively as carbon sources. Results indicate that the recombinant ZM4 acted synergistically with C. cellulolyticum ...
Date: August 2014
Creator: Anieto, Ugochukwu Obiakornobi