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Geologic Setting Of The Phoenix Lander Mission Landing Site, Tabatha Heet

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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 …

Engineering The Optical Properties Of Gold Nanostructures For Biomedical Applications, Leslie Au

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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 AuCl_{2 …}

Design And Synthesis Of Nanomaterials For Surface-Enhanced Raman Scattering, Fuel Cell Technology, And Photonics, Pedro Camargo

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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 …

Genomic Approaches For Pathway Identification In Regenerating Sensory Epithelia Of The Inner Ear, David Alvarado

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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

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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 …

Substance Abuse, Marginalization, And Homelessness: Bayesian Perspectives On A Persisting Problem, Ben Alexander-Eitzman

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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 …

Asset Trajectories And Child Outcomes: Implications For Asset-Based Policies, Vernon Loke

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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 …

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

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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 …

Evaluation Of Pbr In Breast Cancer, Stephany Shockley

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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 …

A New Quantitative Method For The Taxonomic Identification Of Tetrapods, Stephanie Kuster

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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 …

Growth Factor Delivery From Fibrin Matrics Containing Affinity-Based Delivery Systems To Treat Peripheral Nerve Injury, Matthew Wood

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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 …

Uropathogenic E. Coli Employ A Conserved Intracellular Infection Pathway That Can Be Inhibited By Novel Anti-Virulence Therapeutics, Corinne Cusumano

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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 …

Dissecting The Molecular Mechanisms Underlying Synpase Development And Neuronal Functions In Caenorhabditis Elegans, Shuo Luo

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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 …

Genetic And Biochemical Properties Of Arabidopsis Rna Polymerases Iv And V, Jeremy Haag

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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. …

Probing The Early Stages Of Polyglutamine Aggregation With Computational Methods, Andreas Vitalis

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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 …

A Comparison Of Natural And Synthetic Speech: With And Without Simultaneous Reading, Krista Taake

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No abstract provided.

Test Expectancy And Transfer Of Knowledge With Open-Book And Closed-Book Tests, Pooja Agarwal

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Two experiments examined the testing effect with open-book tests, in which students view notes and textbooks while taking the test, and closed-book tests, in which students take the test without viewing notes or textbooks. In the first experiment, subjects studied GRE passages and then took an open- or closed-book test. Open-book testing led to better initial performance than closed-book testing, but this benefit did not persist and both types of testing produced equivalent retention on GRE comprehension questions and transfer questions after a two-day delay. In the second experiment, subjects were informed in advance of the type of immediate or …

Nature And Environment In Nineteenth-Century Austrian Literature, Bartell Berg

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This dissertation illuminates the void of what Christopher Manes refers to in "Nature and Silence" as the "realm of silences, a world of "not saids" called nature, obscured in global claims of eternal truths about human difference, rationality, and transcendence." With the help of ecocriticism, my research explores the development of ecological themes in the writings of four nineteenth-century Austrians from deforestation to industrialization to the growth of gardening culture. In addition, I investigate the nexus between the philosophical and scientific origins of ecology as a discipline and its representation in Austrian literature.

Improving The Cathode Conditions By Pressurizing And Carbon Dioxide Addition To Enhance The Practicality Of Mfc Treatment Of Wastewater, Jeffrey Fornero

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An increasing global energy demand coupled with a more rigorous governmental regulatory environment: including identifying carbon dioxide as a pollutant) is becoming more and more incompatible with engineering practices that were developed in an era of lower energy costs and less regulation. It is, therefore, not a surprise that researchers are looking towards bioelectrochemical systems: BESs) as a potential superior technology to produce environmentally-benign and sustainable energy, replace energy intensive processes, and/or produce chemical products. The overall tenet of my thesis-based research was to understand the important mechanisms that limit the power output for BESs during wastewater treatment and to …

A Framework For Temperature Imaging Using The Change In Backscattered Ultrasonic Signals, Yuzheng Guo

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Hyperthermia is a cancer treatment that elevates tissue temperature to 40 to 43oC. It would benefit from a non-invasive, safe, inexpensive and convenient thermometry to monitor heating patterns. Ultrasound is a modality that meets these requirements. In our initial work, using both prediction and experimental data, we showed that the change in the backscattered energy: CBE) is a potential parameter for TI. CBE, however, was computed in a straightforward yet ad hoc manner. In this work, we developed and exploited a mathematical representation for our approach to TI to optimize temperature accuracy. Non-thermal effects of noise and motion confound the …

The Nonexistence Of Shearlet-Like Scaling Multifunctions That Satisfy Certain Minimally Desirable Properties And Characterizations Of The Reproducing Properties Of The Integer Lattice Translations Of A Countable Collection Of Square Integrable Functions, Robert Houska

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In Chapter 1, we introduce three varieties of reproducing systems—Bessel systems, frames, and Riesz bases—within the Hilbert space context and prove a number of elementary results, including qualitative characterizations of each and several results regarding the combination and partitioning of reproducing systems.

In Chapter 2, we characterize when the integer lattice translations of a countable collection of square integrable functions forms a Bessel system, a frame, and a Riesz basis.

In Chapter 3, we introduce composite wavelet systems and generalize several well-known classical wavelet system results—including those regarding pointwise values of the Fourier transform of the wavelet and scaling function …

Plume Formation In Strongly Temperature-Dependent Viscosity Fluids: Application To Early Mars, Yun Ke

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One of the most prominent features of Mars is the hemispherical dichotomy. The Martian surface consists of a heavily cratered elevated southern hemisphere and a resurfaced depressed northern hemisphere. The dichotomy seems to have formed very early in the history of the planet. Another interesting feature is a remnant magnetization of the crust, which suggests that early Mars had a magnetic field. Investigation of the origin of these features provides insights into the early history of Mars as well as other terrestrial planets including Earth. We develop a hypothesis that the dichotomy is caused by an early transient superplume produced …

Solar Wind Helium, Neon, And Argon In Genesis Aluminum Collectors, Jennifer Mabry

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The Genesis mission collected samples of solar wind: SW) for 853 days and returned them to Earth for analysis. There are several processes that have the potential to significantly alter the composition between the time when SW ions are accelerated away from the sun, to the time the laboratory measurements are made. This work attempts to constrain these sources of fractionation and present the best estimate of the isotopic composition of SW helium, neon, and argon implanted into two different aluminum SW collectors on board the Genesis Mission. We have conducted a diffusion experiment on a similar time scale as …

Zeolites For Cleaner Processes: Alkylation Of Isobutane And N-Butene, Subramanya Nayak

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Large pore beta zeolite with straight and zig-zag channels and USY zeolite with super cages have shown potential to replace toxic and hazardous mineral acids as catalysts in alkylation processes. However, due to rapid deactivation of these zeolites, their acceptance in industrial alkylation has been delayed. In this study we seek a deeper understanding of the kinetics, transport, and sorption of organic molecules used in alkylation processes in nano-porous zeolites. A six lump kinetic model that considers the key reactions for the zeolite catalyzed alkylation process is presented. The influence of different reactions and rate limiting steps on catalyst, and …

Age Differences In Prospective Memory: An Examination Of The Role Of Fluctuations In Executive Control, Shannon Robertson

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Prospective memory: ProM)-remembering to carry out intended actions at appropriate times-is a cognitive function that relies on controlled or automatic processing to various degrees. Age differences in ProM are most likely to be observed on tasks that rely heavily on controlled processes. This is consistent with certain frontal lobe theories of cognitive aging that also make predictions regarding age differences in performance variability on speeded components of ProM tasks that vary in the extent to which controlled processes are required. This study consisted of two experiments designed to test those predictions. In the first experiment, the degree to which controlled …

Improving Biocompatibility By Controlling Protein Adsorption: Modification And Design Of Biomaterials Using Poly(Ethylene Glycol) Microgels And Microspheres, Evan Scott

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Guided by the clinical needs of patients and developments in biology and materials science, the primary focus of the biomaterials field remains at the solid/liquid interface between biomaterial surfaces and biological fluids. For blood-contacting devices, biological responses are initially elicited and directed by proteins that adsorb from this multicomponent solution to form thin films on their surfaces. The identity, conformation, and quantity of adsorbed proteins are related to the properties of a material's surface. For example, hydrophobic surfaces tend to be thrombotic via interactions between platelets and adsorbed fibrinogen, while surface-activation of specific enzymes initiates the coagulation cascade on hydrophilic …

Metal Oxide Semiconductors For Solar Energy Harvesting, Elijah Thimsen

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The correlation between energy consumption and human development illustrates the importance of this societal resource. We will consume more energy in the future. In light of issues with the status quo, such as climate change, long-term supply and security, solar energy is an attractive source. It is plentiful, virtually inexhaustible, and can provide more than enough energy to power society. However, the issue with producing electricity and fuels from solar energy is that it is expensive, primarily from the materials: silicon) used in building the cells. Metal oxide semiconductors are an attractive class of materials that are extremely low cost …

Open Collaborative Mechanical / Product Design - User As Developer A New Design Methodology For Internet Era Business Innovations And Entrepreneurship, Jing Zheng

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In product design and development projects, the most important part is identifying user needs. Traditional methods such as surveys, focus group studies and interviews are expensive and sometime inaccurate in identifying those needs. Inspired by the open source software development, along with the research that has been done on the "lead user" method, the method of using collective customer wisdom to modify old products or even develop new products has become an emerging new design method and is starting to get popularity and success. However, the effectiveness of such method comparing to the traditional face to face "close" development method …

In The Voices Of Men, Beasts, And Gods: Unmasking The Abject Persona In Postwar And Contemporary Japanese Women's Poetry, Lee Friederich

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This dissertation examines the dramatic use of personae of abjection in the works of contemporary and postwar Japanese women poets Ishigaki Rin: 1920-2004), Tomioka Taeko: b. 1935), Yoshihara Sachiko: 1932-2002), It├┤ Hiromi: b. 1955), and Isaka Yok├┤: b. 1949). Recognizing the strong sense of abjection that permeates postwar and contemporary Japanese poetry in general, I explore the ways in which women poets embody the abject--the fantastically grotesque, the deviant and the mortally wounded--in their poetry. Turning away from the dictates of twentieth century critics that women poets write in a transparently autobiographical mode: primarily about their experiences as wives and …

A Comparison Of Iddingsite Alteration In Two Terrestrial Basalts And The Alha 77005 Martian Meteorite Using Raman Spectroscopy And Electron Microprobe Analyses., Karla Kuebler

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The objective of this study is to document the secondary mineral assemblages in two occurrences of terrestrial iddingsite and compare these with the iddingsite in the ALHA 77005 martian meteorite: a lherzolitic shergottite). Short laser Raman spectroscopic traverses: hundreds of μm long) across olivine alteration fronts provide information about changes in the mineral assemblage with alteration. Data from the Raman traverses are combined with data from electron microprobe traverses at the same locations to provide information regarding element mobility near the zones of alteration and to confirm mineral identifications made by Raman spectroscopy. This information is used along with petrographic …