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Geologic Setting Of The Phoenix Lander Mission Landing Site, Tabatha Heet
Geologic Setting Of The Phoenix Lander Mission Landing Site, Tabatha Heet
All Theses and Dissertations (ETDs)
The Phoenix Lander touched down on the northern distal flank of the shield volcano Alba Patera in a ~150 km wide valley underlain by the Scandia Formation. The geomorphology and geology of the landing site is dominated by the ~0.6 Ga, 11.5 km wide, bowl-shaped impact crater, Heimdal, and its areally extensive ejecta deposits. The Lander is located ~20 km to the west of the crater and is sitting on a plains surface underlain by partially eroded Heimdal ejecta deposits. Heimdal was produced by a hypervelocity impact into fine-grained, ice-rich material and is inferred to have produced high velocity winds …
Genomic Approaches For Pathway Identification In Regenerating Sensory Epithelia Of The Inner Ear, David Alvarado
Genomic Approaches For Pathway Identification In Regenerating Sensory Epithelia Of The Inner Ear, David Alvarado
All Theses and Dissertations (ETDs)
The inner ear utilizes sensory hair cells as mechano-electric transducers for sensing sound and balance. In mammals, these sensory hair cells lack the capacity for regeneration and if damaged lead to hearing or balance disorders. However, non-mammalian vertebrates such as birds maintain their regenerative abilities throughout their life. We completed a gene expression profiling time course of regenerating sensory epithelia: SE) in avian cochlea and utricle on a custom transcription factor microarray following damage by laser and chemical ablation and identified genes from known signaling cascades differentially expressed during SE regeneration. In the second study, we selected 27 of these …
Integrated Genomics Of Susceptiblity To Therapy-Related Leukemia, Patrick Cahan
Integrated Genomics Of Susceptiblity To Therapy-Related Leukemia, Patrick Cahan
All Theses and Dissertations (ETDs)
Therapy-related acute myeloid leukemia t-AML is a secondary, generally incurable, malignancy attributable to the chemotherapeutic treatment of an initial disease. Although there is a genetic component to susceptibility to therapy-related leukemias in mice, little is understood either about the contributing loci, or the mechanisms by which susceptibility factors mediate their effect. An improved understanding of susceptibility factors and the biological processes in which they act may lead to the development of t-AML prevention strategies. In this thesis work, we identified expression networks that are associated with t-AML susceptibility in mice. These networks are robust in that they emerge from distinct …
Design And Synthesis Of Nanomaterials For Surface-Enhanced Raman Scattering, Fuel Cell Technology, And Photonics, Pedro Camargo
Design And Synthesis Of Nanomaterials For Surface-Enhanced Raman Scattering, Fuel Cell Technology, And Photonics, Pedro Camargo
All Theses and Dissertations (ETDs)
In the first part of my dissertation, I developed two approaches for selectively probing the SERS activities of individual hot spots, i.e., experimentally detect the SERS signals only for the molecules that are trapped within the hot-spot region in individual Ag nanoparticle dimers. Then, I performed a systematic investigation on the SERS activity of individual dimers composed of two closed spaced Ag nanoparticles. By utilizing Ag nanoparticles displaying a variety of well-defined shapes, sizes and orientations to construct the dimers, I were able to precisely correlate the detected SERS signals to the specific geometry of individual hot spots. In the …
El Arte De La Resistencia: Música, Literatura Y Tradición Oral En La Región Andina Desde El Período Pre Moderno Hasta El Siglo Xvii, Catalina Andrango-Walker
El Arte De La Resistencia: Música, Literatura Y Tradición Oral En La Región Andina Desde El Período Pre Moderno Hasta El Siglo Xvii, Catalina Andrango-Walker
All Theses and Dissertations (ETDs)
This dissertation addresses the construction of Andean subjectivity through the use of musical depictions in 16th and 17th century texts in which European chroniclers characterize the natives based on aspects of sonority, on rudimentary instruments or on musical practices that they considered as paganistic. Music classified as diabolical does not pass out of the category of noise in order to express savagery and disorder. In the grip of a fervent desire for the evangelization of the Andeans the Spaniards translated many sermons into native languages, and adapted the indigenous melodies dedicated to local deities by changing the lyrics so as …
Asset Trajectories And Child Outcomes: Implications For Asset-Based Policies, Vernon Loke
Asset Trajectories And Child Outcomes: Implications For Asset-Based Policies, Vernon Loke
All Theses and Dissertations (ETDs)
Wealth is increasingly recognized as an important determinant in children's human capital trajectories, and a number of countries have proposed or implemented asset-building policies targeting children. Much of the research on assets, however, has focused on the predictors of asset holding, and little is known about asset accumulation trajectories. This is especially so for families with young children. In addition, while studies have demonstrated the positive effects of assets on children's outcomes, few have examined the effects of different asset accumulation patterns and trajectories. This dissertation uses structural equation modeling techniques, including growth mixture models, to further clarify and specify …
Growth Factor Delivery From Fibrin Matrics Containing Affinity-Based Delivery Systems To Treat Peripheral Nerve Injury, Matthew Wood
Growth Factor Delivery From Fibrin Matrics Containing Affinity-Based Delivery Systems To Treat Peripheral Nerve Injury, Matthew Wood
All Theses and Dissertations (ETDs)
This thesis work sought to develop a biomaterial to further the understanding of affinity-based delivery and to serve as a potential treatment for peripheral nerve injury. The use of an affinity-based delivery system: ABDS) with growth factors in a nerve guidance conduit: NGC) was hypothesized to promote nerve regeneration and functional recovery following a critical nerve defect. Evaluation of affinity-based delivery using peptides with varying binding affinity for heparin determined that peptide binding affinity for heparin affected the release rate and biological activity of nerve growth factor: NGF) in vitro. The ABDS presented biologically active NGF, which promoted neurite extension …
Evaluation Of Pbr In Breast Cancer, Stephany Shockley
Evaluation Of Pbr In Breast Cancer, Stephany Shockley
All Theses and Dissertations (ETDs)
The utility of Positron Emission Tomography: PET) in the detection of cancer began with the radiopharmaceutical 2-[18F]fluoro-2-deoxyglucose: FDG) used for measuring altered cellular metabolism. Specific radioligands are being developed to allow non-invasive analysis of protein expression to further characterize tumors. One protein that has been identified as a promising target is the Peripheral Benzodiazepine Receptor: PBR). PBR expression is up-regulated in several cancers, and in many there has been a correlation drawn between increased malignancy and protein expression levels. Therefore, developing PET methodologies to apply for PBR imaging could be an important step in understanding individual tumors as we move …
Probing The Early Stages Of Polyglutamine Aggregation With Computational Methods, Andreas Vitalis
Probing The Early Stages Of Polyglutamine Aggregation With Computational Methods, Andreas Vitalis
All Theses and Dissertations (ETDs)
Exonic CAG repeat diseases are a class of neurodegenerative age-of-onset diseases caused by an unstable trinucleotide expansion in a coding region of a gene. The most prominent example is Huntington's disease: HD) whose symptoms are characterized by loss of motor control and cognitive deficits. For all nine of the known CAG repeat diseases, pathology is ascribed to the mutant proteins which carry expanded stretches of glutamine residues: polyglutamine). The length of the polyglutamine segment is inversely correlated with the disease age-of-onset. Protein aggregates are routinely found in postmortem tissue samples of brains of HD patients. These findings suggest a prominent …
Substance Abuse, Marginalization, And Homelessness: Bayesian Perspectives On A Persisting Problem, Ben Alexander-Eitzman
Substance Abuse, Marginalization, And Homelessness: Bayesian Perspectives On A Persisting Problem, Ben Alexander-Eitzman
All Theses and Dissertations (ETDs)
This dissertation study examined what role substance abuse plays in the marginalized status of homeless adults and how the combined effects of marginalization and substance abuse impact service use and housing status changes over time. The concept of marginalization is used to describe how isolated an individual is from basic needs such as supportive social contact, a safe environment, and legal income options. Thus, the specific aims of this project were to 1) describe longitudinal patterns of substance abuse and marginalization in a homeless population, 2) examine the combined effects of substance abuse and marginalization on housing status changes over …
Genetic And Biochemical Properties Of Arabidopsis Rna Polymerases Iv And V, Jeremy Haag
Genetic And Biochemical Properties Of Arabidopsis Rna Polymerases Iv And V, Jeremy Haag
All Theses and Dissertations (ETDs)
RNA Polymerases IV and V: Pol IV and Pol V) are plant-specific enzyme complexes with subunit homology to RNA Polymerase II: Pol II). The largest subunits in Pol IV and Pol V, NRPD1 and NRPE1 respectively, share a second largest subunit, NRPD2/NRPE2. The evolutionarily conserved Metal A and Metal B binding sites are required for Pol IV and V in vivo function fitting the prediction that these are functional polymerases. The Defective Chloroplast and Leaves-like: DeCL) domain at the C-terminus of both NRPD1 and NRPE1 is also required for complementation but other domains in the NRPE1 CTD are largely dispensable. …
A New Quantitative Method For The Taxonomic Identification Of Tetrapods, Stephanie Kuster
A New Quantitative Method For The Taxonomic Identification Of Tetrapods, Stephanie Kuster
All Theses and Dissertations (ETDs)
The rarity of good fossil samples throughout geologic time frequently makes fossil identification difficult. This dissertation presents a new, multivariate, statistically validated method to identify tetrapods based on quantification of the shapes of microstructural features in cortical bone of the postcranial skeleton. The ultimate goal is to reduce the reliance on rare, near-complete fossil skeletons. The method is validated on a set of 15,745 mammalian microstructural features from eleven diverse species. An additional set of 21,122 microstructural features from one species serve to examine microstructural variation within a single skeleton. Microstructural measurements were made on thin-sections using optical microscopy. Initial …
Dissecting The Molecular Mechanisms Underlying Synpase Development And Neuronal Functions In Caenorhabditis Elegans, Shuo Luo
All Theses and Dissertations (ETDs)
The development and function of the nervous system is under delicate regulation of diverse tissue-derived signals in multi-cellular organisms. In Dr. Nonet's lab, I am using the model organism Caenorhabditis elegans to ask two basic questions: 1) How do different tissues in an organism coordinate to regulate neural functions and behaviors? 2) What controls the development of synapse, the basic unit of the nervous system? These questions divide my dissertation into three parts, with the first two parts related to the first question and the third part to the second question. In the first part of this dissertation, I present …
Engineering The Optical Properties Of Gold Nanostructures For Biomedical Applications, Leslie Au
Engineering The Optical Properties Of Gold Nanostructures For Biomedical Applications, Leslie Au
All Theses and Dissertations (ETDs)
This research investigated the synthesis and optical properties of Au nanostructures with an aim to use them as imaging agents and photothermal transducers for the diagnosis and treatment of cancer. I have produced Au nanocages with hollow interiors and porous walls using the galvanic replacement reaction between Ag nanocubes and AuCl4-. I have engineered these Au nanocages to have localized surface plasmon resonance: LSPR) peaks in the near-infrared region with strong absorption. These optical properties allow for the imaging of biological tissues at deeper penetration and the photoablation of cancer. By replacing AuCl4- with AuCl2 …
Uropathogenic E. Coli Employ A Conserved Intracellular Infection Pathway That Can Be Inhibited By Novel Anti-Virulence Therapeutics, Corinne Cusumano
Uropathogenic E. Coli Employ A Conserved Intracellular Infection Pathway That Can Be Inhibited By Novel Anti-Virulence Therapeutics, Corinne Cusumano
All Theses and Dissertations (ETDs)
Urinary tract infections: UTIs) affect 13 million women annually in the United States and are predominately caused by uropathogenic Escherichia coli: UPEC). In a murine cystitis model, UPEC utilize a multistep pathogenic pathway in which they invade and form intracellular bacterial communities: IBCs) within bladder facet cells. Type 1 pili expressing the adhesin, FimH, are necessary for UPEC binding and invasion of urothelial cells and formation of IBCs. UPEC ultimately disperse from the IBC, many with filamentous morphology, and infect other host urothelial cells. Using a panel of UPEC clinical isolates, this work evaluates the conservation of the IBC pathway …
Surplus Production And Socio-Political Change During The Viking/Medieval Transition: A Paleoethnobotanical Investigation Of Quoygrew Farm, Orkney, Catrina Adams
All Theses and Dissertations (ETDs)
In this dissertation, I examine the process of state formation during the Viking/Medieval transition: c. 1050 A.D.) as it took place in the North Atlantic region. Specifically, I use paleoethnobotanical analysis of remains from Quoygrew farm, an archaeological site located on Westray in the Orkney Islands, to examine the reciprocal relationship between farm production and changes associated with state formation and the Viking/Medieval transition. Towards this goal, I analyzed carbonized plant remains from midden contexts as well as from floor deposits, hearths, pit fills, and dumps. Seed densities and distributions reveal a closely integrated system of farm production including cereal …
Electrocorticographic Neural Correlates Of Arm Movements And Associated Goal Orientation In Humans, Nicholas Anderson
Electrocorticographic Neural Correlates Of Arm Movements And Associated Goal Orientation In Humans, Nicholas Anderson
All Theses and Dissertations (ETDs)
This thesis analyzed the cortical representation of arm kinematics, target encoding, and goal encoding using subdural electrocorticographic: ECoG) recordings in humans. Using a joystick-based visuomotor task, subjects performed both a standard, delayed match-to-sample center-out task as well as a circular tracing task. Spectral analyses of the ECoG signals clearly showed significant cosine tuning for hand velocity, direction, position and speed throughout the cortex. In particular, velocity tuning was best represented spectrally in a high gamma band from around 90-150 Hz in the primary motor cortical regions. In dorsolateral prefrontal cortex: DLPFC), cortical activity in the 150-250 Hz band of the …
Fear And Death In Plato, Emily Austin
Fear And Death In Plato, Emily Austin
All Theses and Dissertations (ETDs)
Plato argues that a perfectly virtuous individual will not fear her own death, nor will she fear or grieve the death of a loved one. In Plato's ideal society, citizens are taught not to fear death and are prohibited from public manifestations of grief. It is by no means self-evident, however, that ridding oneself of the fear of death, even if possible, is ethically or psychologically beneficial. This dissertation examines why Plato thinks that the fear of death is morally inappropriate, why he believes it is nevertheless difficult to overcome, and why he thinks acquiring and sustaining the appropriate attitudes …
Discovery Of Inactive E* Conformations In Thrombin And Other Vitamin K- Dependent Clotting Proteases, Alaji Bah
Discovery Of Inactive E* Conformations In Thrombin And Other Vitamin K- Dependent Clotting Proteases, Alaji Bah
All Theses and Dissertations (ETDs)
Serine proteases of the chymotrypsin family play important roles in the regulation and function of numerous biological processes including digestion, blood coagulation, fibrinolysis, development, fertilization, apoptosis and immunity. For many of these proteases, activity unfolds when a zymogen is activated by limited proteolysis and the associated conformational changes result in the formation of a proper active site and oxyanion hole, both of which are required for efficient hydrolysis of peptide bonds. The transition from zymogen to active enzyme, E, thus provides critical temporal and spatial regulatory mechanism of protease function. Catalytic activity of serine proteases belonging to Vitamin K-dependent clotting …
Essays On The Role Of Law In Judicial Decision Making, Ryan Black
Essays On The Role Of Law In Judicial Decision Making, Ryan Black
All Theses and Dissertations (ETDs)
Forty years ago C. Herman Prichett: 1969) observed that "[P]olitical scientists who have done so much to put the `political' in `political jurisprudence' need to emphasize that it is still `jurisprudence.'" In this dissertation project I seek to help correct this imbalance by providing three fresh approaches to understanding how legal factors influence the choices judges and justices make. Essay 1 focuses on the U.S. Supreme Court's agenda setting decisions. Drawing from the archival papers of Justice Harry A. Blackmun, I analyze the extent to which considerations such as legal conflict among the circuit courts motivate justices to deviate from …
Placing Federal District Courts In The Judicial Hierarchy, Christina Boyd
Placing Federal District Courts In The Judicial Hierarchy, Christina Boyd
All Theses and Dissertations (ETDs)
Over forty years after Richardson and Vines: 1967) complained that federal courts have seldom been investigated as a system of interactions," the same problem continues to plague judicial scholarship, particularly concerning federal district courts. Viewed as the sum of its three essays, this dissertation project seeks to remedy this deficit. The project relies on the collection and coding of thousands of case dockets, opinions, and other court documents across multiple years: 2000-2006 for essay 1, 2000-2004 for essays 2 and 3), nearly 30 district courts, and numerous issues areas that together account for about 40 percent of federal district court …
Quality Of Life And Affect Across The Adult Lifespan, Patrick Brown
Quality Of Life And Affect Across The Adult Lifespan, Patrick Brown
All Theses and Dissertations (ETDs)
The premise of this dissertation is based on the work of M. Powell Lawton, in particular his theories of Environmental Press: Lawton and Nahemow, 1973) and the Dual-Channel Hypothesis: Lawton, 1996; Lawton, Winter, Kleban, & Ruckdeschel, 1999). Study 1 used a correlational approach to test Lawton and colleagues: 1999) model in a community sample of people across the adult lifespan, thereby expanding previous findings to individuals under age 60. Study 2 used an experimental approach to determine if individuals are affectively susceptible to differing environmental conditions based on their performance on a cognitive task. Whereas Study 1 provided a naturalistic …
Using Repeated Testing And Variable Encoding To Promote Transfer Of Learning, Andrew Butler
Using Repeated Testing And Variable Encoding To Promote Transfer Of Learning, Andrew Butler
All Theses and Dissertations (ETDs)
Within the literature on transfer of learning, relatively few studies have investigated how the conditions of initial learning can be arranged to increase the likelihood of successful transfer. The present research investigated whether test-enhanced learning can be used to promote transfer. More specifically, four experiments examined how repeated testing and repeated studying affected retention and transfer of facts and concepts. Subjects studied prose passages and then either repeatedly re-studied or took tests on the material. One week later, they took a final test that either had the same questions: Experiment 1), new inferential questions within the same knowledge domain: Experiments …
Chinese Spirit, Russian Soul, And American Materialism: Images Of America In Twentieth-Century Chinese And Russian Travelogues, Rumyana Cholakova
Chinese Spirit, Russian Soul, And American Materialism: Images Of America In Twentieth-Century Chinese And Russian Travelogues, Rumyana Cholakova
All Theses and Dissertations (ETDs)
Chinese Spirit, Russian Soul, and American Materialism: Images of America in Twentieth-Century Chinese and Russian Travelogues This study is concerned with the process of understanding and representation of the Other in travel narratives and the role of the traveler's cultural tradition and ideological beliefs in this process. I explore the images of the United States in some of the most influential twentieth-century Chinese and Russian travelogues. There are deep cultural differences between China and Russia, yet their relationships with the West show certain similarities. The first important parallel is that the contacts with the West was a catalyst in the …
An Investigation Of Acetobacter Aceti N5-Carboxyaminoimidazole Ribonucleotide Mutase And Its Pure-Purk Operon, Charles Constantine
An Investigation Of Acetobacter Aceti N5-Carboxyaminoimidazole Ribonucleotide Mutase And Its Pure-Purk Operon, Charles Constantine
All Theses and Dissertations (ETDs)
Acetobacter aceti oxidizes ethanol to acetic acid. While the membrane-permeable acetic acid is toxic to many bacteria, A. aceti survives exposure to acetic acid by tolerating cytoplasmic acidification. The ability to tolerate an acidic cytoplasm suggests that proteins from A. aceti are unusually suited to function in an acidic environment. The ability to tolerate an acidic cytoplasm raises additional questions about biosynthetic pathways that employ acid-labile intermediates. To examine how A. aceti metabolism may have adapted to function under acidic conditions, a biosynthetic conversion involving an acid-labile metabolite has been selected for study. The enzyme N5-carboxyaminoimidazole ribonucleotide mutase: PurE) catalyzes …
Mammalian Postcranial Evolution And Primate Extinction In The Middle Eocene Of North America, Rachel Dunn
Mammalian Postcranial Evolution And Primate Extinction In The Middle Eocene Of North America, Rachel Dunn
All Theses and Dissertations (ETDs)
Primates constituted a dominant part of the mammalian faunas of North America during the early and middle parts of the Eocene: 55-46 ma). Beginning in the Uintan North American Land Mammal Age: 46-42 ma) primates declined in diversity and abundance in the Rocky Mountain region. This decline has been linked to the recession of tropical rain forests out of northern latitudes at that time. Climatic change of this magnitude would presumably have an impact on the contemporary mammalian faunas, with reduction or extinction of forest groups like primates, but perhaps radiation of mammals that preferred more open habitats such as …
Mechanisms Of Feedback In The Visual System, Adam Eggebrecht
Mechanisms Of Feedback In The Visual System, Adam Eggebrecht
All Theses and Dissertations (ETDs)
Feedback is an ubiquitous feature of neural systems though there is little consensus on the roles of mechanisms involved with feedback. We set up an in vivo preparation to study and characterize an accessible and isolated feedback loop within the visual system of the leopard frog, Rana pipiens. We recorded extracellularly within the nucleus isthmi, a nucleus providing direct topographic feedback to the optic tectum, a nucleus that receives the vast majority of retinal output. The optic tectum and nucleus isthmi of the amphibian are homologous structures to the superior colliculus and parabigeminal nucleus in mammals, respectively. We formulated a …
Geoarchaeology Of The Danilo Bitinj And Pokrovnik Sites, Dalmatia, Croatia, Cynthia Fadem
Geoarchaeology Of The Danilo Bitinj And Pokrovnik Sites, Dalmatia, Croatia, Cynthia Fadem
All Theses and Dissertations (ETDs)
This dissertation examines the paleoecology of earliest European agriculture via geological and geochemical analysis of two Neolithic settlements in central Dalmatia, Croatia. The Early Farming in Dalmatia Project, of which this geoarchaeological study is a part, is a case study in the adoption and environmental impact of agricultural technology. Dalmatia served to transmit agriculture from the domestication centers of the Middle East to mainland Europe. The record of neolithization in this region is incomplete - biased toward caves, upland storage locales. The landscape setting of the foraging-to-farming behavioral evolution is missing, even as Neolithic transition research turns to more complex …
Identification And Characterization Of Novel Astroviruses, Stacy Finkbeiner
Identification And Characterization Of Novel Astroviruses, Stacy Finkbeiner
All Theses and Dissertations (ETDs)
Approximately 1.8 million children die from diarrhea annually, and millions more suffer multiple episodes of nonfatal diarrhea. Despite the availability of improved molecular diagnostics to detect the known viral agents, the etiology of a large proportion of diarrheal cases is unknown. In fact, it is estimated that no causative agent can be identified in up to 40% of sporadic cases or in gastroenteritis outbreaks. Detection of novel or unexpected viruses is the first step in identifying agents that could potentially close the diagnostic gap and pave the way for the development of more comprehensive preventative measures and better treatments. This …
Adaptive Middleware For Resource-Constrained Mobile Ad Hoc And Wireless Sensor Networks, Chien-Liang Fok
Adaptive Middleware For Resource-Constrained Mobile Ad Hoc And Wireless Sensor Networks, Chien-Liang Fok
All Theses and Dissertations (ETDs)
Mobile ad hoc networks: MANETs) and wireless sensor networks: WSNs) are two recently-developed technologies that uniquely function without fixed infrastructure support, and sense at scales, resolutions, and durations previously not possible. While both offer great potential in many applications, developing software for these types of networks is extremely difficult, preventing their wide-spread use. Three primary challenges are: 1) the high level of dynamics within the network in terms of changing wireless links and node hardware configurations,: 2) the wide variety of hardware present in these networks, and: 3) the extremely limited computational and energy resources available. Until now, the burden …