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Description
Coal bed natural gas (CBNG) production has become a significant contribution to the nation's energy supply. Large volumes of water are generated as a byproduct of CBNG extraction, of which this "product water" is relatively high in sodium. High sodicity reduces water quality and limits environmentally compliant disposal options for

Coal bed natural gas (CBNG) production has become a significant contribution to the nation's energy supply. Large volumes of water are generated as a byproduct of CBNG extraction, of which this "product water" is relatively high in sodium. High sodicity reduces water quality and limits environmentally compliant disposal options for producers. Crop irrigation with CBNG product water complies with state and federal laws and is a disposal method that also provides a beneficial use to private landowners. However, this disposal method typically requires gypsum and sulfur soil amendments due to the high levels of sodium in the water, which can reduce soil infiltration and hydraulic conductivity. In this study, I tested a new product called Salt Extractor that was marketed to CBNG producers to ameliorate the negative effects of high sodicity. The experiment was conducted in the Powder River Basin of Wyoming. I used a random block design to compare the soil and vegetation properties of plots following application with CBNG product water and treatments of either Salt Extractor, gypsum and sulfur (conventional), or no treatment (control). Data was analyzed by comparing the amount of change between treatments after watering. Results demonstrated the known ability of gypsum and sulfur to lower the relative sodicity of the soil. Plots treated with Salt Extractor, however, did not improve relative levels of sodicity and exhibited no favorable benefits to vegetation.
ContributorsAdams, Shelly (Author) / Hall, Sharon (Thesis advisor) / Chew, Matt (Committee member) / Stromberg, Juliet (Committee member) / Arizona State University (Publisher)
Created2011
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Description
Infections caused by the Hepatitis C Virus (HCV) are very common worldwide, affecting up to 3% of the population. Chronic infection of HCV may develop into liver cirrhosis and liver cancer which is among the top five of the most common cancers. Therefore, vaccines against HCV are under intense study

Infections caused by the Hepatitis C Virus (HCV) are very common worldwide, affecting up to 3% of the population. Chronic infection of HCV may develop into liver cirrhosis and liver cancer which is among the top five of the most common cancers. Therefore, vaccines against HCV are under intense study in order to prevent HCV from harming people's health. The envelope protein 2 (E2) of HCV is thought to be a promising vaccine candidate because it can directly bind to a human cell receptor and plays a role in viral entry. However, the E2 protein production in cells is inefficient due to its complicated matured structure. Folding of E2 in the endoplasmic reticulum (ER) is often error-prone, resulting in production of aggregates and misfolded proteins. These incorrect forms of E2 are not functional because they are not able to bind to human cells and stimulate antibody response to inhibit this binding. This study is aimed to overcome the difficulties of HCV E2 production in plant system. Protein folding in the ER requires great assistance from molecular chaperones. Thus, in this study, two molecular chaperones in the ER, calreticulin and calnexin, were transiently overexpressed in plant leaves in order to facilitate E2 folding and production. Both of them showed benefits in increasing the yield of E2 and improving the quality of E2. In addition, poorly folded E2 accumulated in the ER may cause stress in the ER and trigger transcriptional activation of ER molecular chaperones. Therefore, a transcription factor involved in this pathway, named bZIP60, was also overexpressed in plant leaves, aiming at up-regulating a major family of molecular chaperones called BiP to assist protein folding. However, our results showed that BiP mRNA levels were not up-regulated by bZIP60, but they increased in response to E2 expression. The Western blot analysis also showed that overexpression of bZIP60 had a small effect on promoting E2 folding. Overall, this study suggested that increasing the level of specific ER molecular chaperones was an effective way to promote HCV E2 protein production and maturation.
ContributorsHong, Fan (Author) / Mason, Hugh (Thesis advisor) / Gaxiola, Roberto (Committee member) / Chang, Yung (Committee member) / Chen, Qiang (Committee member) / Arizona State University (Publisher)
Created2011
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Description
Two nearly homogenous 60 acre watersheds near Heber, Arizona, within the Apache-Sitgreaves National Forest, were burned at moderate and high severities during the 2002 Rodeo-Chediski wildfire. Each watershed had 30 permanent plots located on it from earlier studies. In 2011, nearly 10 years following the fire, the plots were re-measured

Two nearly homogenous 60 acre watersheds near Heber, Arizona, within the Apache-Sitgreaves National Forest, were burned at moderate and high severities during the 2002 Rodeo-Chediski wildfire. Each watershed had 30 permanent plots located on it from earlier studies. In 2011, nearly 10 years following the fire, the plots were re-measured to determine how fire severity affects the long term vegetative recovery of this ecosystem; specifically herbaceous production and tree regeneration and density. Canopy cover, litter depth, herbaceous weight, herbaceous cover and shrub cover are vital indicators of herbaceous production, and were found to be significantly different between the sites. Canopy cover and litter depth were found to be significantly higher on the moderate site while herbaceous weight, herbaceous cover and shrub cover were found to be significantly higher on the high site. Tree densities of the three present tree species, ponderosa pine, alligator juniper, and gambel oak, were measured and divided into five size classes to distinguish the diversity of the communities. The mean densities for each species and size class were analyzed to determine if there were any statistically significant differences between the sites. Ponderosa pine saplings (regeneration) were found to have no significant differences between the sites. Juniper and oak saplings were found to be significantly higher on the high site. The remaining four ponderosa pine size classes were found to be significantly higher on the moderate site while the remaining four size classes for juniper and oak were found to have no statistical differences between the sites. Further analysis of the tree proportions revealed that the ponderosa pine species was significantly higher on the moderate site while juniper and oak were significantly higher on the high site. Species specific proportion analysis showed that the ponderosa pine size classes were significantly different across the sites while the juniper and oak size classes showed no significant differences between the sites. Within the ponderosa pine size classes, saplings were found to be significantly higher on the high site while the remaining four classes were significantly higher on the moderate site.
ContributorsNeeley, Heidi L (Author) / Alford, Eddie (Thesis advisor) / Pyne, Stephen (Committee member) / Brady, Ward (Committee member) / Arizona State University (Publisher)
Created2012
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Description
The advent of advanced reproductive technologies has sparked a number of ethical concerns regarding the practices of reproductive tourism and commercial gestational surrogacy. In the past few decades, reproductive tourism has become a global industry in which individuals or couples travel, usually across borders, to gain access to reproductive services.

The advent of advanced reproductive technologies has sparked a number of ethical concerns regarding the practices of reproductive tourism and commercial gestational surrogacy. In the past few decades, reproductive tourism has become a global industry in which individuals or couples travel, usually across borders, to gain access to reproductive services. This marketable field has expanded commercial gestational surrogacy--defined by a contractual relationship between an intending couple and gestational surrogate in which the surrogate has no genetic tie to fetus--to take on transnational complexities. India has experienced extreme growth due to a preferable combination of western educated doctors and extremely low medical costs. However, a slew of ethical issues have been brought to the forefront: the big ones manifesting as concern for reduction of a woman's worth to her reproductive capabilities along with concern for exploitation of third world women. This project will be based exclusively on literature review and serves primarily as a call for cultural competency and understanding the circumstances that gestational surrogates are faced with before implementing policy regulating commercial gestational surrogacy. The paper argues that issues of exploitation and commodification hinge on constructions of motherhood. It is critical to define and understand definitions of motherhood and how these definitions affect a woman's approach to reproduction within the cultural context of a gestational surrogate. This paper follows the case study of the Akanksha Infertility Clinic in northern India, a surrogacy clinic housing around 50 Indian surrogates. The findings of the project invokes the critical significance of narrative ethics, which help Indian surrogates construct the practice of surrogacy so that it fits into cultural comprehensions of Indian motherhood--in which motherhood is selfless, significant, and shared.
ContributorsMoorthy, Anjali (Author) / Robert, Jason S (Thesis advisor) / Hurlbut, Benjamin (Committee member) / Ellison, Karin (Committee member) / Arizona State University (Publisher)
Created2011
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Description
Studies have demonstrated that anthocyanins can function as antioxidants, reduce inflammation, and improve dyslipidemia. Tart cherries are anthocyanin-rich, making them particularly attractive as a functional food to improve cardiovascular disease (CVD) risk. There have been few published studies to date examining the impact of tart cherries on biomarkers of dyslipidemia

Studies have demonstrated that anthocyanins can function as antioxidants, reduce inflammation, and improve dyslipidemia. Tart cherries are anthocyanin-rich, making them particularly attractive as a functional food to improve cardiovascular disease (CVD) risk. There have been few published studies to date examining the impact of tart cherries on biomarkers of dyslipidemia and inflammation, particularly in overweight and obese individuals at high risk for these conditions. This study evaluated the effect of consuming 100% tart cherry juice daily on blood lipids including total cholesterol, low-density lipoprotein cholesterol (LDL-C), calculated very low density lipoprotein cholesterol (VLDL-C), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), and the CVD risk ratios, as well as the inflammatory biomarkers interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), monocyte chemotactic protein-1 (MCP-1), and erythrocyte sedimentation rate (ESR) following a 4-week period. Based on the high anthocyanin content of tart cherries, it was hypothesized that the lipid and inflammatory profiles would be significantly improved following the intervention. A total of 26 men and women completed this 4-week randomized, single-blind, placebo-controlled, crossover study. Participants were randomized to drink either 8 ounces of placebo beverage or tart cherry juice daily for 4 weeks. Following a 4-week washout period, the alternate beverage was consumed. Ultimately, this investigation demonstrated no statistically significant alterations in any of the lipid or inflammatory biomarkers when analyzed across time and between interventions (p > 0.05). As expected, glucose and insulin parameters remained stable over the duration of the study, as well as self-reported physical activity level, total calorie consumption, and macronutrient intake. However, trans-fat was reported to be significantly higher during the cherry arm of the study as compared to the placebo arm (p < 0.05), potentially confounding other results. Although the results of this study were equivocal, it is feasible that a higher dose, longer treatment duration, or more susceptible target population may be required to elicit significant effects. Consequently, further investigation is necessary to clarify this research.
ContributorsColes, Katie (Author) / Martin, Keith R. (Thesis advisor) / Traustadottir, Tinna (Committee member) / Vega-Lopez, Sonia (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Once considered an abundant species in the eastern United States, local populations of red-shouldered hawks, Buteo lineatus, have declined due to habitat destruction. This destruction has created suitable habitat for red-tailed hawks, Buteo jamaicensis, and therefore increased competition between these two raptor species. Since suitable habitat is the main limiting

Once considered an abundant species in the eastern United States, local populations of red-shouldered hawks, Buteo lineatus, have declined due to habitat destruction. This destruction has created suitable habitat for red-tailed hawks, Buteo jamaicensis, and therefore increased competition between these two raptor species. Since suitable habitat is the main limiting factor for raptors, a computer model was created to simulate the effect of habitat loss in central Maryland and the impact of increased competition between the more aggressive red-tailed hawk. These simulations showed urban growth contributed to over a 30% increase in red-tailed hawk habitat as red-shouldered hawk habitat decreased 62.5-70.1% without competition and 71.8-76.3% with competition. However there was no significant difference seen between the rate of available habitat decline for current and predicted development growth.
ContributorsMurillo, Crystal (Author) / Whysong, Gary (Thesis advisor) / Alford, Eddie (Committee member) / Miller, William (Committee member) / Arizona State University (Publisher)
Created2011
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Description
Within ethics, a number of scholars advocate an interdisciplinary approach of combining the two traditionally different professions of science and philosophy with the confidence that this collaboration will be a mutually beneficial experience. Current ethicist-scientist interactions include embedded-ethicists and research ethics consultation services. Both methods are employed with the hope

Within ethics, a number of scholars advocate an interdisciplinary approach of combining the two traditionally different professions of science and philosophy with the confidence that this collaboration will be a mutually beneficial experience. Current ethicist-scientist interactions include embedded-ethicists and research ethics consultation services. Both methods are employed with the hope that they will reduce social and ethical problems that could arise from scientific research, and enhance the reflective capacity of investigative teams. While much effort has been put forth in the endeavor of creating ethicist-scientist interactions, there remains opportunity to refine these new interaction models to make them more robust. There is need for ethicists to understand the context of ethical decision-making in the laboratory. By extension, before interacting with scientists in a research lab, research ethicists ought to have the ability to understand the science and also be familiar with the different factors that influence scientific research, such as funding, productivity requirements, time constraints, politics of laboratories and institutional reward structures. Through literature review and the analysis of qualitative data obtained from the ethnographic study in a neuroscience laboratory, this thesis explores the strengths and weaknesses of ethicist-scientist interactions and aims to understand the culture, traditions and values of this community and their perspectives on their role as scientists and their relationship to ethics. This study shows that the quantity and quality of ethics discussions in the lab are limited and dictated by time constraints and minimal incentives. Other influencing factors are the researchers' perspectives on ethics and how they view their role as a scientist in relation to the public.
ContributorsMin, Gyongeun Catherine (Author) / Ellison, Karin (Thesis advisor) / Robert, Jason S (Thesis advisor) / Minteer, Ben A (Committee member) / Arizona State University (Publisher)
Created2012
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Description
The spread of invasive species may be greatly affected by human responses to prior species spread, but models and estimation methods seldom explicitly consider human responses. I investigate the effects of management responses on estimates of invasive species spread rates. To do this, I create an agent-based simulation model of

The spread of invasive species may be greatly affected by human responses to prior species spread, but models and estimation methods seldom explicitly consider human responses. I investigate the effects of management responses on estimates of invasive species spread rates. To do this, I create an agent-based simulation model of an insect invasion across a county-level citrus landscape. My model provides an approximation of a complex spatial environment while allowing the "truth" to be known. The modeled environment consists of citrus orchards with insect pests dispersing among them. Insects move across the simulation environment infesting orchards, while orchard managers respond by administering insecticide according to analyst-selected behavior profiles and management responses may depend on prior invasion states. Dispersal data is generated in each simulation and used to calculate spread rate via a set of estimators selected for their predominance in the empirical literature. Spread rate is a mechanistic, emergent phenomenon measured at the population level caused by a suite of latent biological, environmental, and anthropogenic. I test the effectiveness of orchard behavior profiles on invasion suppression and evaluate the robustness of the estimators given orchard responses. I find that allowing growers to use future expectations of spread in management decisions leads to reduced spread rates. Acting in a preventative manner by applying insecticide before insects are actually present, orchards are able to lower spread rates more than by reactive behavior alone. Spread rates are highly sensitive to spatial configuration. Spatial configuration is hardly a random process, consisting of many latent factors often not accounted for in spread rate estimation. Not considering these factors may lead to an omitted variables bias and skew estimation results. The ability of spread rate estimators to predict future spread varies considerably between estimators, and with spatial configuration, invader biological parameters, and orchard behavior profile. The model suggests that understanding the latent factors inherent to dispersal is important for selecting phenomenological models of spread and interpreting estimation results. This indicates a need for caution when evaluating spread. Although standard practice, current empirical estimators may both over- and underestimate spread rate in the simulation.
ContributorsShanafelt, David William (Author) / Fenichel, Eli P (Thesis advisor) / Richards, Timothy (Committee member) / Janssen, Marco (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Human recreation on rangelands may negatively impact wildlife populations. Among those activities, off-road vehicle (ORV) recreation carries the potential for broad ecological consequences. A study was undertaken to assess the impacts of ORV on rodents in Arizona Uplands Sonoran Desert. Between the months of February and September 2010, rodents were

Human recreation on rangelands may negatively impact wildlife populations. Among those activities, off-road vehicle (ORV) recreation carries the potential for broad ecological consequences. A study was undertaken to assess the impacts of ORV on rodents in Arizona Uplands Sonoran Desert. Between the months of February and September 2010, rodents were trapped at 6 ORV and 6 non-ORV sites in Tonto National Forest, AZ. I hypothesized that rodent abundance and species richness are negatively affected by ORV use. Rodent abundances were estimated using capture-mark-recapture methodology. Species richness was not correlated with ORV use. Although abundance of Peromyscus eremicus and Neotoma albigula declined as ORV use increased, abundance of Dipodomys merriami increased. Abundance of Chaetodipus baileyi was not correlated with ORV use. Other factors measured were percent ground cover, percent shrub cover, and species-specific shrub cover percentages. Total shrub cover, Opuntia spp., and Parkinsonia microphylla each decreased as ORV use increased. Results suggest that ORV use negatively affects rodent habitats in Arizona Uplands Sonoran Desert, leading to declining abundance in some species. Management strategies should mitigate ORV related habitat destruction to protect vulnerable populations.
ContributorsReid, John Simon (Author) / Brady, Ward (Thesis advisor) / Miller, William (Committee member) / Bateman, Heather (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Many studies over the past two decades examined the link between climate patterns and discharge, but few have attempted to study the effects of the El Niño Southern Oscillation (ENSO) on localized and watershed specific processes such as nutrient loading in the Southwestern United States. The Multivariate ENSO Index (MEI)

Many studies over the past two decades examined the link between climate patterns and discharge, but few have attempted to study the effects of the El Niño Southern Oscillation (ENSO) on localized and watershed specific processes such as nutrient loading in the Southwestern United States. The Multivariate ENSO Index (MEI) is used to describe the state of the ENSO, with positive (negative) values referring to an El Niño condition (La Niña condition). This study examined the connection between the MEI and precipitation, discharge, and total nitrogen (TN) and total phosphorus (TP) concentrations in the Upper Salt River Watershed in Arizona. Unrestricted regression models (UMs) and restricted regression models (RMs) were used to investigate the relationship between the discharges in Tonto Creek and the Salt River as functions of the magnitude of the MEI, precipitation, and season (winter/summer). The results suggest that in addition to precipitation, the MEI/season relationship is an important factor for predicting discharge. Additionally, high discharge events were associated with high magnitude ENSO events, both El Niño and La Niña. An UM including discharge and season, and a RM (restricting the seasonal factor to zero), were applied to TN and TP concentrations in the Salt River. Discharge and seasonality were significant factors describing the variability in TN in the Salt River while discharge alone was the significant factor describing TP. TN and TP in Roosevelt Lake were evaluated as functions of both discharge and MEI. Some significant correlations were found but internal nutrient cycling as well as seasonal stratification of the water column of the lake likely masks the true relationships. Based on these results, the MEI is a useful predictor of discharge, as well as nutrient loading in the Salt River Watershed through the Salt River and Tonto Creek. A predictive model investigating the effect of ENSO on nutrient loading through discharge can illustrate the effects of large scale climate patterns on smaller systems.
ContributorsSversvold, Darren (Author) / Neuer, Susanne (Thesis advisor) / Elser, James (Committee member) / Fenichel, Eli (Committee member) / Arizona State University (Publisher)
Created2012