Now showing items 1-20 of 14574

    • Participatory Democracy, Pluralism, and the Rational Model in Natural Resource Planning: A Case Study of the San Pedro River Initiative Process, Arizona, U.S.A.

      Evans, Luke T. (The University of Arizona., 2002)
      An analysis and critique is conducted of pluralism, the rational model, and participatory democracy in relation to public participation in natural resource planning and policy development. Each theory is evaluated in terms of efficacy, representation and access, information exchange and learning, continuity of participation, and decision-making authority. A case study is used to assess elements of each theory in an actual public participation process, utilizing the above criteria. The study indicates that the need for efficiency precludes the use of practices that would more thoroughly involve the public in decision making processes, and that policy making tends to revert to more traditional, expert-dominated, and exclusive public processes despite efforts to the contrary. Finally, the analysis questions the utility of comprehensive public involvement in natural resource policy making and planning given the constraints of existing legal mandates, polarized public opinions, and the need for decisions made in the larger public interest.
    • Genetic Analysis of Mountain Lion (Puma concolor) Feces from Kofa National Wildlife Refuge, Arizona

      Naidu, Ashwin (The University of Arizona., 2009)
      Investigations on recent records of mountain lions (Puma concolor) and concurrent declines in desert bighorn sheep (Ovis canadensis mexicana) on Kofa National Wildlife Refuge have necessitated the determination of the number of mountain lions and their diet on the refuge. Using genetic analysis, we identified mountain lion feces/scats (n=53) from the Kofa and Castle Dome Mountains in southwestern Arizona. We identified 11 individual mountain lions that included at least 6 males and 2 females. We also identified prey species from bone and connective tissue remains inside the mountain lion scats. Our data suggest that a majority of mountain lion diet (62 %) on the refuge is mule deer (Odocoileus hemionus). These estimates greatly enhance our knowledge of mountain lions in an area where, historically, their presence was considered transient. Additionally, recognizing the need for reliable species identification and to improve species identification from non-invasive samples, we developed a Polymerase Chain Reaction (PCR) primer set that would enable the amplification of the complete cytochrome b gene from a large number of mammalian species. DNA sequence information obtained from the use of this primer set can be used for the development of mammalian species’ databases and referencing. Overall, this project demonstrates the efficacy of genetic techniques and their potential to provide reliable and necessary information on elusive species to wildlife managers.
    • HCMV Manipulation of Host Cholesteryl Ester Metabolism

      Dahlmann, Elizabeth Alan (The University of Arizona., 2019)
      Human cytomegalovirus (HCMV) is a β-herpesvirus that infects over 50% of people above the age of 40. Once infected, HCMV establishes a lifelong latent infection with periodic reactivation. Most infections are asymptomatic. However, infection in immunocompromised patients may result in fatal HCMV-related complications. Further, congenitally-acquired HCMV infection is the leading cause of birth defects in the United States. The HCMV virion contains a large double-stranded DNA genome encapsidated by a protein shell that is surrounded by a lipid membrane. Like all enveloped viruses, HCMV steals host lipids to generate its envelope membrane. While previous studies demonstrate that HCMV replication requires lipid metabolism, the details of virally-induced lipid changes remain poorly defined. We performed an untargeted lipidomic screen using liquid chromatography high resolution tandem mass spectrometry to identify and quantitatively measure how infection alters the lipidome of cells. We found that HCMV increases cholesteryl esters (CE) by 24 hours post infection. CE lipids are synthesized by sterol O-acyltransferase 1 (SOAT1) attaching a fatty acyl-CoA to a cholesterol molecule. I hypothesized that early stages of HCMV replication induce CE biosynthesis and that CE are required for viral replication. In support of our hypothesis, we found HCMV induces SOAT1 gene expression. Further, HCMV immediate early pUL37x1 is partially responsible for virally-induced CE accumulation. We found that treating infected cells with a SOAT1 inhibitor blocked CE production and infection. Overall, our findings suggest that HCMV induces CE synthesis that can be targeted to block infection.
    • Development and Evaluation of Habitat Suitability Criteria for Native Fishes and Assessment of the Relationship Among Riparian Areas and Stream Macrohabitats Type and Fish Presence in Four Central Arizona Streams

      Nemec, Zach (The University of Arizona., 2018)
      Habitat loss is an important reason for fish fauna declines in the southwestern U.S. Several studies have defined habitat conditions for selected native fish species in Arizona, yet habitat use can vary across streams due to a variety of biological and physical factors. In addition, previous studies have focused on effects of instream habitat characteristics and less on how riparian areas structure aquatic communities of the Southwest. Riparian areas affect aquatic communities in a variety of ways, including structuring instream habitat. Macrohabitat (riffle, run, pool) is an important determinant of fish use, and little is known about the effect of riparian vegetation and associated land use activities on the formation of macrohabitat. Therefore, the objectives of my study were to 1) evaluate suitable habitat for native Arizona species, and 2) to investigate the relationships among riparian vegetation and stream macrohabitats type and fish presence in four central Arizona streams. Fish and habitat data were collected in four streams along the Mogollon Rim in Arizona during the 2017 summer field season at base flow conditions. I used the National Hydrography Dataset (NHD) and National Agricultural Imagery Program (NAIP) aerial imagery to estimate the amount of vegetation cover within the riparian areas of each stream. I developed habitat suitability criteria for four native species in three streams. Most generalized criteria did not transfer among study streams, similar to finding from past studies suggesting that stream-specific criteria were more accurate. I found that Smallmouth Bass and Red Shiner had a negative relationship to canopy cover, possibly explained by high temperature tolerances of both species. Desert Sucker and Speckled Dace presence were positively related to presence of riffle habitat, as has been noted in previous habitat studies. Riffle habitat was positively related to increases in riparian vegetation cover. These results can inform researchers, agencies and stakeholders who study and manage Arizona’s riparian areas and instream habitat.
    • Role for Selective Sphingosine 1-Phosphate Receptor 1 Modulation During Acute Ischemic Injury in an Experimental Male and Female Mouse Stroke Model

      Shi, Samuel (The University of Arizona., 2018)
      Acute ischemic stroke (AIS) is a neurological disease caused by cessation of blood flow to the brain. Globally, AIS is the second leading cause of death in addition to being the leading cause of long term disability. Effective treatment strategies for ischemic stroke are limited; novel effective therapies are in great demand. Stroke pathophysiology is characterized by an initial ischemic event followed by a deluge of typical secondary responses including inflammation and vascular endothelial dysfunction. Recently the endogenous sphingolipid pathway has emerged as possible therapeutic target for attenuating ischemic brain damage. The sphingosine signaling pathway comprises of sphingosine-1-phosphate as well as its associated receptors that regulate a wide variety of physiological mechanisms, some of which are involved in AIS pathophysiology. In this thesis I will review the sphingosine signaling pathway biology as well as relevant effects on vascular function and inflammation. In addition, I will present and discuss data gathered during my thesis studies investigating sphingosine 1-phosphate receptor modulation in an experimental male and female mouse model of ischemic stroke and reperfusion.
    • Prevalence and Comorbidity Burden Among Adults with Psoriasis in the United States

      Margraf, David James (The University of Arizona., 2018)
      Background: Information is sparse concerning the prevalence and associated comorbidities of psoriasis in the United States (U.S.) civilian noninstitutionalized population. The objectives of this study were to determine the national proportion of patients who self-report psoriasis diagnosed by a physician and to explore the comorbidity burden of these patients. Methods: This study used ten years of retrospective, cross-sectional data from the Medical Expenditure Panel Survey (MEPS) (2006–2015). The study population included adults (age≥18 years) who did not die during the calendar year the survey was completed and had an ICD-9-CM code of 696.xx (psoriasis and similar disorders) based on individual self-reports of illness. Subtypes were categorized as those with and without joint involvement to assess the number of persons who had skin-only psoriasis, and those who may have psoriatic arthritis via reporting joint pain in the last 12 months. Bivariate, multivariate, and propensity score matched methods using logistic regression were performed, accounting for multiple comparisons, to appraise the association of diseases between the psoriasis case and control groups. Results: The self-reported prevalence of previously diagnosed psoriasis was found to be 0.80% (n=719, 95% CI=0.73-0.88%) of the population on average over the ten year study period. Psoriasis patients with skin-only manifestations accounted for 0.30% (n=269, 95% CI=0.25-0.34%) of the population versus those who may have psoriatic arthritis 0.51% (n = 450, 95% CI=0.44-0.57%). Analyses showed psoriasis patients were more than twice as likely to report other autoimmune diseases than those without psoriasis. The bivariate [Odds Ratio (OR)=2.72], multivariate [Adjusted Odds Ratio (AOR)=2.50], and propensity score method (AOR=2.62) produced approximately similar magnitudes of association at the P<0.00125 level. Similar findings were seen with rheumatoid arthritis, mood disorders, gastroesophageal reflux disease (GERD), and COPD. Conclusions: These study findings are some of first analyses of prevalence and comorbidity patterns of psoriasis based on a nationally representative survey of the U.S. civilian noninstitutionalized population. The prevalence of psoriasis is low, but there are several associated comorbid conditions and clusters of diseases such as other autoimmune diseases like rheumatoid arthritis that may benefit from future analyses to appropriately plan for treatment, and insurance needs. These associations may help assess healthcare expenditures, healthcare use, and provide context to disease etiology.
    • Habitat Suitability Criteria for Nonnative Species and Relationships between Fish Populations and Flow Regime in Four Arizona Streams

      Lee, Larissa N. (The University of Arizona., 2018)
      Nonnative species invasions and streamflow alteration are two of the primary causes of native fish depletion in the southwestern U.S. Previous research in Arizona has focused on the habitat needs of native species, without understanding the habitat selection of nonnative species. Additionally, fish populations and streamflow can vary significantly throughout a single Arizona stream, so it is important to understand how spatially variable flows affect fish assemblages. This research has two objectives: 1) to define suitable habitat for nonnative species, and 2) to explore the relationships between the distributions of various fish species throughout time and space in four Arizona streams. Four streams in the Mogollon Rim region of Arizona were sampled during summer base flow conditions (May – October) of 2017 to collect information on fish distributions and habitat conditions. A 20-year dataset from fish sampling in the Verde River by the Arizona Game and Fish Department was used to examine temporal shifts in fish assemblages as they relate to streamflow. Streamflow data from USGS stream gages, the USGS StreamStats application, and the National Hydrography Dataset (NHD) provided metrics to characterize streamflow throughout the study sites. These metrics included estimates of 2-year flood flows, 10-year flood flows, 100-year flood flows, mean annual flows, mean channel velocity, stream power at mean flow, and stream power at 2-year flood flow. I defined suitable habitat for seven nonnative species across these four streams, and results indicated that nonnative species were generally using warmer temperatures and shallower depths compared to available habitat, but many habitat results varied by species. Relationships between streamflow characteristics and species assemblages also varied by species. I found that certain native species, like Sonora Sucker, consistently demonstrated positive relationships with spatial flow characteristics across all four streams, demonstrating a preference for areas with higher velocities, flow, and power. Results for other species were more variable by stream, and differences often split the four study streams into similarities among Tonto Creek and the Verde River, the two larger systems dominated by nonnative species, as opposed to the Blue River and Eagle Creek, the two smaller systems dominated by nonnative species. These results can inform decision-makers and fisheries managers in streamflow allocation, habitat restoration, and nonnative species removals.
    • The Status and Vitality of Moroccan Tamazight and Darija

      Graybill, Aaron James (The University of Arizona., 2019)
      Various social and political factors determine language status and vitality. These factors are fluid and change over time, making status harder to measure. However, through an overview of the recent political and educational history, and current events in Morocco, I chart the status changes of Darija (Moroccan Arabic) and Tamazight (Berber) using the UNESCO language vitality framework. The results show that Tamazight is shifting in its respective status and vitality. In contrast, Darija, while maintaining linguistic vitality demographically and historically, lacks institutional support. This lack of institutional support has implications for key vitality factors and stems from its subordinate place in relation to Standard Arabic. Tamazight, after the recent history of marginalization, is beginning to enjoy increased institutional support. The result is an increase in Tamazight broadcasting and textbooks as well as the appointment of an Amazigh Prime Minister. However, despite this support, Tamazight is still in a demographic decline, and it remains to be seen whether government interventions will slow or reverse this language shift.
    • Using High-Definition Underwater Videography and Social Psychology to Increase Public Interest in Rare Fishes

      Ulrich, Taylor (The University of Arizona., 2018)
      Generating public interest in fish and their biology is often challenging. Many aquatic species are cryptic and largely invisible to the public. Therefore, it is important to be innovative in attempts at increasing public awareness of fish and in elevating the visibility of fisheries topics to broad audiences. Technological innovations now provide fisheries biologists, managers, and researchers with improved means for documenting fish in their natural habitat via underwater videography. I investigated such means to identify cost efficient and easy to use methods for capturing and creating high quality, high definition, and informative underwater videos. I tested 1) a variety of filming equipment including cameras and camera recording settings, lenses, batteries, and memory cards; 2) active and passive camera deployment techniques; and 3) a variety of free and paid postproduction software. The highest quality footage, i.e., the highest resolution, clearest, and most stable footage, was obtained using a GoPro action camera deployed underwater in a stationary position mounted to a metal base plate using a combination of stock and macro lenses, and filming in 4K resolution at 30 frames per second. The final production videos were created using Adobe Premiere Pro. Furthermore, apathy of the public toward these fishes and their ecosystems hinders their conservation. After I filmed using the described methods, I then used that video footage and created low-cost, educational video presentations featuring the unique and rare desert fishes of Nevada and Death Valley, California. Using these videos, I tested the inclusion of various widely recognized social psychology principles (anthropomorphic [Chan 2012]; authority, commitment, rarity, reciprocity, similarity and liking, social proof [Cialdini, 2009]) in these videos to test their effectiveness at increasing presentation effectiveness when displayed to an audience that was apathetic towards the environment. Social psychology additions were screened by panels of university faculty, graduate students, undergraduate students, and human subjects’ experts to ensure they were ethical and truthful, not altering the accuracy of the information presented. I used text-only treatments surveyed through Qualtrics in the first round of treatment videos; enhanced text and different background image treatments surveyed through Qualtrics in the second round of treatment videos and enhanced text and different background image treatment videos surveyed through Mturk in the third round of treatment videos. In all three rounds of testing, regardless of control/treatment group, viewers' knowledge significantly improved post-viewing (Round 1: t = 37.809, df = 473, P < 0.001; Round 2: t = 45.256, df = 431, P < 0.001; and Round 3: t = 43.860, df = 352, P < 0.001). However, no significant differences in change in knowledge scores were found among groups in Round 1, 2, or 3. In addition, post-viewing New Ecological Paradigm (NEP) score, a measure of environmental attitude, was significantly higher than the pretest score, regardless of group (Round 1: t = 7.805, df = 498, P < 0.001; Round 2: t = 3.459, df = 451, P < 0.001; Round 3: t = 5.824, df = 352, P < 0.001). Significant differences in change in NEP scores among groups were only found in Round 3 (F = 2.967; df = 7, 345; P = 0.00493) with the reciprocity group scores significantly higher than similarity and anthropomorphic group scores (adjusted P-values of 0.0223 and 0.0336 respectively). These results indicate that all types of underwater videos, no matter the treatment type, have a positive effect on previously-apathetic viewers’ knowledge and ecological attitude. In addition, adding specific social psychology elements in videos had a subtle, but positive effect on viewers’ learning outcome and ecological attitude. Videos are a powerful tool to increase knowledge and ecological attitude among apathetic viewers. Research on the further development of ethical social psychological methods to help educate the public on conservation subjects is an important avenue of future investigation.
    • Sedimentary Megasequences of Colombian Basin, Offshore Colombia

      Basabe Triana, Yeison Daniel (The University of Arizona., 2018)
      The Colombian Basin is located in the northern Colombian Caribbean Sea and overlies a large portion of the Caribbean plate. It is the largest of several Caribbean basins with an average depth of about 3.5 km. The tectonics of the Caribbean region are complex and the Caribbean Plate itself has been interpreted both as an oceanic plate that migrated from the Pacific and as having evolved “in situ” after the separation of South and North America. Given its location, insights into the geology of the Colombian Basin play an essential role in informing our understanding of these controversies. Previous geophysical studies such as gravimetric, refraction and reflection studies showed that the basin is partly underlain by anomalously thickened oceanic crust that corresponds to the Caribbean Oceanic Plateau, adjacent to areas of typical oceanic crust as occurs in the Eastern Venezuela basin. However, previous data acquired does not cover most of the central and eastern parts of the Colombia basin. This thesis evaluates a total of 6390 km of newly available multichannel 2D seismic reflection data acquired in the deep-sea Colombian Basin by the Colombian Agency of Hydrocarbons (ANH); the seismic data cover most of the central and eastern parts of the Colombian Basin and permit expansion of earlier studies that focused on the western Colombian Basin. The seismic reflection data was tied to well DSDP 153 from the Deep Sea Drilling Project and seven horizons were tracked throughout the area, and three main mega-sequences were identified, which record the evolution of the basin. Two different types of basement crust (thickened oceanic plateau or thin oceanic crust) were mapped, and it is apparent that the differential nature of oceanic crust controls overlying thicknesses of Late Cretaceous to Middle Miocene sedimentary rocks and the subduction angle beneath the South Caribbean Deformed Belt. Initial increases in the thickness of trench-filling sedimentary units in the Eocene confirms the initiation of subduction by this time. Since the Middle Miocene, sedimentary rock units of the Magdalena fan have had a dominant role in the sediment supply of the basin and these sedimentary rocks record the eastward migration of the Caribbean Plate and avulsion processes of the Magdalena river. After the late Miocene, channel-levee complexes (CLC) and very large mass-transport complexes (MTC) are identified and mapped in the study area. A Pleistocene mass transport complex has been mapped, and its area and calculated volume showed that it is larger than 95% of the mass-transport complexes compiled from the geological record around the world.
    • Examining Depressive Symptoms and Academic Satisfaction among Latino Youth: Associations between Boundary Ambiguity of Family Relationships and Familism

      Rodas, Jose Miguel (The University of Arizona., 2018)
      Guided by the theory of ambiguous loss, this study examined how youth options of potential change in family relationships (i.e., ambiguous loss) and their perceptions of this loss (i.e., boundary ambiguity) are associated with depressive symptoms and academic satisfaction. Further, I also examined how familism is associated with depressive symptoms and academic satisfaction. This was a cross-sectional self-report survey study of low-income Latino youth (N = 123, age 14-18 years). Results demonstrate that boundary ambiguity from the ambiguous loss of family relationships was positively associated with depressive symptoms; whereas familism behaviors were negatively associated with depressive symptoms. In comparison, only higher familism behaviors were associated with higher academic satisfaction. These findings illuminate how familism behaviors are a positive and protective factor for both depressive symptoms and academic satisfaction for Latino adolescents. However, when Latino youth report higher boundary ambiguity about ambiguous loss of family relationships, they report more depressive symptoms. These findings demonstrate that family relationships can have both positive and negative associations for well-being of Latino youth.
    • Creating Amitabha: The Deification of Yongming Yanshou From the Wuyue to the Ming

      Baldry, T. Adam (The University of Arizona., 2018)
      Yongming Yanshou (904-975) was an influential Buddhist figure during the Wuyue Period (907-978) known for his writings, teachings, and tenure as abbot at Lingyin Temple 靈隱寺 and Yongming Temple 永明寺 (later known as Jingci Temple 淨慈寺). A look at his early biographies, such as his biography included in the Song gaoseng zhuan 宋高僧傳 [Song Biographies of Eminent Monks] (988), indicates that he was an eminent monk worthy of veneration. Yet, by the Ming Dynasty (1368-1644) the narrative surrounding his life had changed significantly. He was being claimed as an incarnation of Amitabha Buddha and was worshiped as such. This study attempts to discover how this drastic change to Yanshou’s narrative developed. By tracing through Yanshou’s biographies it is evident his narrative was manipulated, growing his spiritual powers and abilities, slowly deifying him in the process. By the time of the Ming Dynasty these changes to Yanshou’s narrative had been fossilized. Three individuals named Yuanjin Dahuo (1576-1627), Yu Chunxi (jinshi 1583), and Huang Ruheng (1558-1626) were deeply influenced by the Yanshou they knew in the Ming. After rediscovering Yanshou’s relics, these three individuals produced a new biography of Yanshou, the Yongming daoji 永明道蹟 [Traces of Yongming’s Path] (1607), as an effort to raise funds to build a new stupa for Yanshou at Jingci Temple. Within the Yongming daoji, and in later records surrounding the building of Yanshou’s stupa that are collected in the Chijian jingci sizhi 勅建淨慈寺志 [Officially Built Jingci Temple Monastic Gazetteer] (1805), Dahuo, Yu, and Huang claimed Yanshou was an incarnation of Amitabha Buddha, Dahuo being the first to do so. Yu and Huang later interpolated Yanshou’s narrative by including four known figures as other incarnations of Yanshou and Amitabha (two having lived before Yanshou’s birth and two living after his death). By placing Yanshou within a series of incarnations Yu and Huang were able to solidify their claim of Yanshou as an incarnation of Amitabha. Yanshou was thereby fully deified into Amitabha during the Ming Dynasty.
    • Electrochemical Measurement of Lead Levels in Drinking Water

      Feather, John Dekrafft (The University of Arizona., 2018)
      Many metal ions in water pose health and environmental hazards. Electrochemical measurements are simple, inexpensive, and reliable means to find the concentration of such metal ions in water, including lead. The Environmental Protection Agency (EPA) requires corrective action when lead concentrations in drinking water are greater than 15 ppb (7.24∗10−8 M). Even though clean water may be sent out from a central processing facility, there are still possible sources of contamination on the way to the faucet. Lead materials are in service which can corrode and introduce lead ions into residential drinking water. Underpotential deposition (UPD) is an electrochemical method which has been developed for measuring lead ion concentrations relevant to maintaining safe drinking water. UPD uses bonding interactions between a lead ion and electrode to reversibly form up to a monolayer of metal atoms on a surface at electrical potentials more positive than bulk lead reduction. The electrode coverage is proportional to lead ions in water. Gold metal is an electrode for measuring lead ions in water over wide ranges of pH and conductivities typically found in drinking water. When the gold electrode potential is scanned in the UPD potential region, a sharp current peak at a specific potential occurs for levels of lead up to and below 20 ppb in water. UPD offers a good alternative to stripping voltammetry for measuring the concentration of ions, like Pb2+, in water.
    • Kinetics and Mechanism of Energetic Events in Deposition Reactor Systems for Semiconductor Fabrication

      Chang, YenHsun (The University of Arizona., 2018)
      The study of the thesis is about the energetic material that are used in semiconductor industries. A process model is developed to simulate the processes that results in some run-away exothermic reactions involving reactive deposited materials in the downstream of typical deposition reactors used in semiconductor manufacturing, such as chemical vapor deposition(CVD) and atomic level deposition(ALD). The potential sources of energetic material have been pointed out in the study. This model takes into account various transport and reactions involved in the process and reveals the details of the mechanism that trigger these uncontrolled energetic reactions and the potential damaging effects due to formation of hotspots. Using the developed model, a parameter study is conducted to see the effect of various parameters on this process. In particular, the concentration of reactants, the accumulation due to competition between the deposition and reaction, the gas flow rate and the properties of reactants and reactions play the key role in the trigger mechanism as well as the location and time of hot spot formation. Based on the results, a number of techniques are suggested to minimize and mitigate the occurrence of these energetic events.
    • Occurrence of Salmonella in Canals Delivering Irrigation Waters used for Produce Production

      Torres, Monique A. (The University of Arizona., 2018)
      With the increase in produce consumption in recent years, the risk of foodborne illness increases as well. It is estimated that 1,940 reported cases of foodborne illnesses were associated with the consumption of produce in the United States in 2015. Salmonella enterica is one of the top bacterial foodborne pathogens of concern and causes gastroenteritis estimated to have caused about 1,300 reported produce-borne outbreaks in the US/year. One of the ways Salmonella can travel to produce fields and contaminate produce is via irrigation water. The objective of this study was to detect the presence of Salmonella and indicator organisms of fecal contamination including Escherichia coli, coliforms, and coliphages in constructed canal systems which deliver irrigation waters for produce production. A total of 355 irrigation water samples were collected from various irrigation canals in Southern Arizona from January 2017 to August 2017. All samples were tested for general water quality or physiochemical parameter and analyzed using enrichment media, selective media, and confirmational methods for the presence of Salmonella enterica. This analysis yielded 11.6% (41/355) positive isolates with an average concentration of 4.10 MPN/100 ml. E. coli and coliforms were detected via IDEXX Colilert ®kit and IDEXX Quanti-Tray/2000® resulting in 97% (344/355) and 100% (355/355) positive samples, respectively. F+ and somatic coliphages were detected using the FastPhage™ MPN Quanti-tray method and resulted in 35.4% (62/175) and 60.5% (127/210) positive samples, respectively. The results of this study indicate that Salmonella and fecal indicator organisms were found at detectable levels in irrigation waters used in crop production. This implies the potential to cause foodborne illnesses, if the crops are contaminated with irrigation water that contains pathogens. A quantitative microbial risk assessment analysis was performed, using a Monte Carlo simulation and the exponential dose response model, to determine the spread of Salmonella to lettuce from irrigation water. The probability of causing infection annually was estimated as 2.1x10-7 and 5.1 x 10-5 for concentrations of 4.1MPN/100 ml and 1000MPN/100 ml at day 0 following the irrigation event, respectively. This is lower than the EPA standard of 1 in 10,000 per year, making this concentration of Salmonella in irrigation canal waters relatively safe for produce consumers. However, additional sampling and data would help further determine potential risks of irrigation water and contamination potentials.
    • Reverse Engineering of Ancient Ceramic Technologies from Southeast Asia and South China

      Kivi, Nicholas (The University of Arizona., 2019)
      Ceramic technologies of Myanmar and South China were analyzed in order to determine characteristic traits and technological origins. Given Myanmar’s geographically strategic position between China and Southwest Asia, its ceramic history needs to be reevaluated among the distinct traditions of Southeast Asia. The ceramics of Myanmar show evidence of imitation China and Southwest/Central Asia using locally sourced materials, giving support to Dr. Myo Thant Tyn’s theory of the convergence of the Chinese and Southwest/Central Asian ceramic traditions in Myanmar. Seven ceramic technologies of Myanmar were analyzed: celadons, black-glazed jars (lead-barium and lead-iron-manganese glazes), brown ash glaze ware, green and opaque white-painted glaze ware and turquoise-glazed, coarse-bodied white earthenware. Celadon glazes and brown glazes were made with ash, similar to the Chinese celadon tradition. Green-and-white opaque ware utilized copper-green colorant glaze decoration with tin and lead oxides as opacifying agents on low-fired oxidized bodies. Both these traditions are probably derived from Southwest Asian ceramic and glass traditions. High-soda, copper-turquoise glazes on coarse white earthenware bodies are influenced by Southwest and Central Asian low-fire ceramic and glass traditions. Black-glazed, “Martaban”-style storage jars were variable in body and glaze technology and are still of indeterminable technological origin. A phase-separated glaze was analyzed that had a similar phase-separated appearance to northern Chinese Jun ware. Additionally, two black-glazed ware types from South China with vertical streaking phase separation were analyzed: Xiba kiln of Sichuan and Jianyang kilns of Fujian. The recently discovered and excavated Xiba kiln made experimental and striking stoneware bowls similar to Jianyang “hare’s fur” ware. Reverse engineering the manufacture of Xiba kiln ware determined that Xiba was an innovative site that imitated Jianyang ware aesthetically but not technologically. Xiba and Jianyang do not have any connection to the six Burmese glaze styles, however, future analyses of Southeast Asian ceramics can use the data for comparison and variability research.
    • An 8 Channel Imager/Polarimeter for Astronomical Observations

      Taylor, Brian William (The University of Arizona., 2019)
      Discussion of optical designs and instrument polarization for an Eight Channel Imager/Po- larimeter are presented. The designs will cover the optical and Near Infrared(NIR) wavelengths from 330nm to 2400nm in a simultaneous acquisition mode for eight distinct broad bands. The simultaneous acquisition provides capabilities to study unique events such as supernovae, Gamma Ray Bursts(GRBs), and occultations. It also increases the efficiency of long term monitoring pro- grams such as the study of blazars. The selection of the wavelength bands were specifically chosen to match the Sloan Digital Sky Survey(u′, g′, r′, i′,z′) and the 2MASS(J,H,K) catalogs.
    • Stress in Augmented Reality Human Computer Interfaces

      Elbishari, Yunes M Y (The University of Arizona., 2019)
      The ability of a user to control their attention within an Augmented Reality (AR) Human Computer Interaction (HCI) is an unreliable quality for the design of an AR system. An alternative design approach is to adopt adaptive HCIs that adapt to specific user needs. One user need is to manage stress levels. Stress is an issue because it affects user performance. Often users are not aware of their stress levels, therefore a User Interface (UI) that independently identifies stress and automatically adapts to it would be very beneficial. The present study examines the research questions: how would a UI adapt to stress and what would be the utility of such be? The study included both descriptive and experimental elements. The descriptive element reasons from fundamental neuroscience and psychology that stress is an important factor in user performance and that a UI that reduced excessive stress would have utility, namely it would enable improved user performance. The experimental element proved a means to measure stress via a proxy. The experiment utilized a situation demanding an AR UI, that is both real world and computer created data were required to complete the required tasks: one “performance” task for which user performance mattered and a “distraction” task to ensure the user’s cognitive engagement was saturated. The experiment demonstrated that stress (measured by proxy) is directly correlated to stimuli complexity of the AR UI and that user performance in an AR UI is inversely correlated to stress. These facts together provide a strong indication that an AR UI that adapts to the stress proxy would provide significant value to the user.
    • PARP Activation, NAD+ Depletion, and Energy Dysregulation Following Traumatic Brain Injury

      Schmidt, Julian Christopher (The University of Arizona., 2018)
      Traumatic brain injury (TBI) is characterized by a sudden concussive (direct force or shock wave) blow to the head, in which traumatic biomechanical forces are transferred throughout the head and neck. Damage to neural tissue occurs due to rapid acceleration and deceleration forces of the brain, culminating upon impact of the brain with the interior of the skull. At the molecular level, TBI generates a host of physiological responses, which manifest in many different ways. The focus of this thesis will be on the trajectory that progresses through 1) brain acceleration forces, 2) force-induced DNA damage in neurons and glia, 3) activation of DNA repair mechanisms (specifically, poly ADP-ribose polymerase (PARP)), 4) nicotinamide adenine dinucleotide (NAD+) depletion via PARP assembly, 5) the effect of NAD+ depletion on energy metabolism, and 6) the potential value of an NAD+ modulator (nicotinamide riboside chloride, NR-Cl) in modulating this effect. Pathologically, reactive oxygen species (ROS) and other free radicals are generated following TBI. The generation of these radicals leads to DNA damage in affected regions of the brain. In response to DNA damage, PARP, a molecule responsible for initiating DNA repair, is activated and begins to polymerize. The assembly of PARP is directly dependent upon nicotinamide adenine dinucleotide (NAD+) cannibalization, in which the ADP-ribosyl subunit of NAD+ is used to build the large poly ADP-ribose (PAR) polymer. One PAR assembly can consume up to 200 ADP-ribose subunits derived from NAD+. This leads to depleted cellular NAD+ and diminished energy metabolism, the severity of which is dependent upon the extent of injury and degree of PARP activation. In this thesis, I will summarize the molecular mechanisms associated with PARP activation, NAD+ depletion, energy dysregulation, and the potential value of NR-Cl as a potential therapeutic agent in mild and moderate TBI.
    • CC16 Depletion in the Lung Due to Early Life Biomass Exposures

      Calderon, Stephanie Marie (The University of Arizona., 2019)
      Millions of people across the globe are affected by respiratory diseases that include chronic obstructive pulmonary disease (COPD), asthma, emphysema, as well as cancer. COPD is the third leading cause of death worldwide due to the increase in global air pollution and smoking. Currently, there is no treatment that can change the outcome of the disease. The clinical manifestations of COPD are lung function decline and recurrent episodes of exacerbations (Knabe, 2015). Many pollutants that can lead to COPD come from sources such as wood and coal burning, cigarette smoke, and industrial air pollution. Many people across the world rely on the combustion of biomass for fuel as energy for heating and cooking. Biomass smoke exposures are recognized as a significant public health issue due to respiratory health implications. This paper will provide a review and synthesis of human and mice studies of lung insults that cause inflammatory diseases such as COPD and explore the role of club cell protein 16 in the development of disease following exposure to biomass smoke.