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2010

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Optical-Resolution Photoacoustic Microscopy, Song Hu Jan 2010

Optical-Resolution Photoacoustic Microscopy, Song Hu

All Theses and Dissertations (ETDs)

Optical microscopy, providing valuable biomedical insights at the cellular and organelle levels, has been widely recognized as an enabling technology. Mainstream optical microscopy technologies, including single-/multi-photon fluorescence microscopy and OCT, have demonstrated extraordinary sensitivities to fluorescence and optical scattering contrasts, respectively. However, the optical absorption contrast of biological tissues, which encodes essential physiological/pathological information, has not yet been fully assessable. The emergence of biomedical photoacoustics has led to a new branch of optical microscopy--OR-PAM. As a valuable complement to existing optical microscopy technologies, OR-PAM detects optical absorption contrasts with exquisite sensitivity: i.e., 100%). Combining OR-PAM with fluorescence microscopy or optical-scattering-based …

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Parallelization Of Dynamic Programming Recurrences In Computational Biology, Arpith Jacob Jan 2010

Parallelization Of Dynamic Programming Recurrences In Computational Biology, Arpith Jacob

All Theses and Dissertations (ETDs)

The rapid growth of biosequence databases over the last decade has led to a performance bottleneck in the applications analyzing them. In particular, over the last five years DNA sequencing capacity of next-generation sequencers has been doubling every six months as costs have plummeted. The data produced by these sequencers is overwhelming traditional compute systems. We believe that in the future compute performance, not sequencing, will become the bottleneck in advancing genome science. In this work, we investigate novel computing platforms to accelerate dynamic programming algorithms, which are popular in bioinformatics workloads. We study algorithm-specific hardware architectures that exploit fine-grained …

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Nmr Search For Mobile, Aluminum-Bearing Species During Reactions Of Sodium Alanate, Timothy Ivancic Jan 2010

Nmr Search For Mobile, Aluminum-Bearing Species During Reactions Of Sodium Alanate, Timothy Ivancic

All Theses and Dissertations (ETDs)

NaAlH4 has become the archetypal complex: ionic-covalent) hydrogen storage solid, since the discovery in 1997 that titanium and some other metals catalyze the reaction in both directions. Given that spatially separated NaH and Al under excess H2 pressure can form NaAlH4, we have hypothesized a mobile Al- or Na- bearing intermediate species in the reaction scheme. 27Al in situ NMR has been used to discover such a new species during dehydriding of NaAlH4. Importantly, the new species can also be formed under excess H2 pressure without net evolution of Al and H2 …

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Front End Specifications And The Propagation Of Construction Claims, Sidney Hymes Jan 2010

Front End Specifications And The Propagation Of Construction Claims, Sidney Hymes

All Theses and Dissertations (ETDs)

Front End Specifications represent the administrative, organizational, performance and payment requirements for construction projects. The vast majority of construction contracts use Front End Specifications, either from an independent source or prepared in-house. In spite of the crucial role of Front End Specifications, little is known regarding whether Front End Specifications increase or decrease claims in construction. Further, no published reports to date have investigated whether construction claims are systematically related to Front End Specification complexity, partnering, business size or document authorship. In the present quantitative study, participants: n = 150) from the construction industry, including contractors, subcontractors, designers and owners, …

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Piezoelectric Control Of Structures Prone To Instabilities, Sunjung Kim Jan 2010

Piezoelectric Control Of Structures Prone To Instabilities, Sunjung Kim

All Theses and Dissertations (ETDs)

Thin-walled structures such as stiffened panels fabricated out of high strength materials are ubiquitous in aerospace structures. These are prone to buckle in a variety of modes with strong possibility of adverse interaction under axial compression and/or bending. Optimally designed stiffened panels, at an appropriate combination of axial compression and suddenly applied lateral pressure undergo large amplitude oscillations and may experience divergence. Under aerodynamic loading, they can experience flutter instability with the amplitudes of oscillations attaining a limit: LCO) or escalating without any limit. Control of structures prone to these forms of instability using piezo-electric actuators is the theme of …

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The Pursuit Of Accreditation In Children's Mental Health Care: Motivations, Experiences, And Perceptions, Madeline Lee Jan 2010

The Pursuit Of Accreditation In Children's Mental Health Care: Motivations, Experiences, And Perceptions, Madeline Lee

All Theses and Dissertations (ETDs)

Accreditation is a growing, worldwide phenomenon and thousands of mental health organizations spend considerable amounts of money and resources towards achieving and maintaining accreditation. Despite its widespread use, the empirical and theoretical literature on accreditation is sparse. This study is the first step towards examining accreditation's potential as an organizational intervention to improve the quality of mental health services. Using a mixed methods multiple case study design, this exploratory study aimed to 1) understand agencies' motivations to pursue accreditation, 2) explore agencies' experiences with the accreditation process, 3) identify mental health care workers' perceptions of how the accreditation process may …

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Pattern Formation And Magnetism In Pulsed Laser-Induced Self-Organized Nanostructures From Single And Bilayer Metallic Films, Hare Krishna Jan 2010

Pattern Formation And Magnetism In Pulsed Laser-Induced Self-Organized Nanostructures From Single And Bilayer Metallic Films, Hare Krishna

All Theses and Dissertations (ETDs)

Self-organization via nanosecond pulsed laser melting of thin metal films is attractive as a reliable and low cost method to create surface metallic nanostructures. The potential applications of these resulting structures are related to their magnetic, optical, plasmonic, and magneto-optical properties, such as in high density magnetic storage, energy harvesting, and sensing. In this dissertation experimental and theoretical mechanisms of nanoscale patterning by dewetting self-organization was explored in nanoscopic thickness single and bilayer metal films. Magnetism in the resulting nanostructures was also explored. Experimental techniques included thin film deposition, laser irradiation, scanning and transmission electron microscopy, atomic force and magnetic …

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Essays On Accounting Conservatism, Bong Hwan Kim Jan 2010

Essays On Accounting Conservatism, Bong Hwan Kim

All Theses and Dissertations (ETDs)

I examine the role of accounting conservatism in the debt market and equity market. In the first essay I examine whether post-borrowing accounting conservatism is related to initial debt-covenant slack. I find firms with low debt-covenant slack display a smaller increase in conservatism after borrowing compared to firms with high debt-covenant slack. I further find that this relation is more pronounced when the cost of debt-covenant breach is greater and is less pronounced when lenders have stronger monitoring incentives. This study supports the debt covenant hypothesis. The second essay investigates the impact of financial market competition on a firm's choice …

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Predictors Of Intercultural Competence Among International Volunteers, Benjamin Lough Jan 2010

Predictors Of Intercultural Competence Among International Volunteers, Benjamin Lough

All Theses and Dissertations (ETDs)

International volunteering and service: IVS) has the potential to promote intercultural competence, or "the ability to communicate effectively and appropriately in intercultural situations based on one's intercultural knowledge, skills, and attitudes": Deardorff, 2008: 33). Although conditions of IVS vary greatly across program models, nearly all claim that volunteering will increase intercultural competence. Contact theory, transformative learning theory, and various stage theories of intercultural learning all suggest, however, that cultural contact will only improve a volunteer's intercultural competence under certain conditions. This dissertation builds on previous scholarship by isolating four characteristics that vary across institutional models, and testing how these variations …

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Cultural Anxieties And Institutional Regulation: "Specialized" Mental Healthcare And "Immigrant Suffering" In Paris, France, Stéphanie Larchanché Jan 2010

Cultural Anxieties And Institutional Regulation: "Specialized" Mental Healthcare And "Immigrant Suffering" In Paris, France, Stéphanie Larchanché

All Theses and Dissertations (ETDs)

This dissertation looks at "specialized" mental healthcare expertise in France as a lens through which to address the institutional management and representations of cultural difference in France today. By "specialized" mental healthcare centers, I refer structures that provide culturally-sensitive mental health services to immigrants specifically. I identify and explore three contemporary expert approaches: namely, transcultural psychiatry, clinical medical anthropology, and ethnoclinical mediation. By providing a genealogy of specialized mental healthcare institutions, and by construing them as "meta-discursive nodes"--that is, as points of encounter between state, institutional, and individual ideologies--I provide an analysis of the cultural anxieties, contradictions and double-binds that …

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Characterization Of Streptolysin O As The Translocator For The Cytolysin-Mediated Translocation Process In Streptococcus Pyogenes, N'Goundo Magassa Jan 2010

Characterization Of Streptolysin O As The Translocator For The Cytolysin-Mediated Translocation Process In Streptococcus Pyogenes, N'Goundo Magassa

All Theses and Dissertations (ETDs)

Secretion of toxins into host cells is an important component of microbial pathogenesis. In order to gain access to the host cell cytosol, toxins must cross the plasma membrane, traverse the membrane of endocytic vesicles, or cross the membrane of organelles. The process cytolysin-mediated translocation: CMT) in Streptococcus pyogenes uses the pore-forming protein streptolysin O: SLO) to translocate the S. pyogenes NAD+-glycohydrolase: SPN) effector into the cytosol of eukaryotic host cells. Although, the fundamentals of this protein translocation process are established the details of the mechanism remain elusive. The current studies illustrate that the translocation process is more complex than …

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Enhancing Nonlinear Ultrasonic Methods For Laboratory And Clinical Applications, Christopher Lloyd Jan 2010

Enhancing Nonlinear Ultrasonic Methods For Laboratory And Clinical Applications, Christopher Lloyd

All Theses and Dissertations (ETDs)

This thesis addresses the underlying physics associated with nonlinear ultrasonic field propagation, measurements of the nonlinear properties of materials, and mechanisms contributing to the observed systematic variation of backscattered ultrasonic energy from the heart over the heart cycle. Studies were performed to address the reliability of the methods of measurement used for the quantitative characterization of nonlinear phenomena and to explore the utility of these methods. This thesis examines the measurement of nonlinear acoustic properties of materials using several methods, including the transmission of ultrasound through the material, as well as the backscattered signal from a region of interest within …

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Synthesis, Structure And Spectroscopy Of Heteropentadienyl-Cobalt Complexes, Bryn Lutes Jan 2010

Synthesis, Structure And Spectroscopy Of Heteropentadienyl-Cobalt Complexes, Bryn Lutes

All Theses and Dissertations (ETDs)

A heteropentadienyl ligand is a molecule in which the terminal carbon of a pentadienyl ligand has been replaced with a heteroatom: O, PR, NR, S, SiR2). The study of heteropentadienyl-transition metal complexes has been an active area of research in the last decade, and has recently received significant attention in the chemical literature. These molecules can now be synthesized by generalized methods, allowing their unique reactivity to be the focus of current research. These molecules have shown the ability to adopt and shift between a variety of bonding modes, opening coordination sites at the metal center and showing promise for …

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Functional Genomic Examinations Of Interactions Between Common Members Of The Human Gut Microbiota, Michael Mahowald Jan 2010

Functional Genomic Examinations Of Interactions Between Common Members Of The Human Gut Microbiota, Michael Mahowald

All Theses and Dissertations (ETDs)

The adult human gut microbiota consists of hundreds to thousands of bacterial species, the majority belonging to the Bacteroidetes and the Firmicutes. Differences in the balance between these phyla has been linked to obesity in mice and humans. However, little is known about their interactions in vivo. I have used comparative and functional genomics, proteomics and biochemical assays to identify the ways they marshal their genomic resources to adapt to life together in the distal gut. I first annotated the complete genome sequences of two human gut Bacteroidetes (Bacteroides vulgatus and Parabacteroides distasonis) and two Firmicutes (Eubacterium rectale and E. …

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Modeling Aerial Refueling Operations, Allen Mccoy Jan 2010

Modeling Aerial Refueling Operations, Allen Mccoy

All Theses and Dissertations (ETDs)

Aerial Refueling: AR) is the act of offloading fuel from one aircraft: the tanker) to another aircraft: the receiver) in mid flight. Meetings between tanker and receiver aircraft are referred to as AR events and are scheduled to: escort one or more receivers across a large body of water; refuel one or more receivers; or train receiver pilots, tanker pilots, and boom operators. In order to efficiently execute the Aerial Refueling Mission, the Air Mobility Command: AMC) of the United States Air Force: USAF) depends on computer models to help it make tanker basing decisions, plan tanker sorties, schedule aircraft, …

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Give Me Your Engineers, Your Ph.D.S, Yearning To Fund My Welfare State. Fiscal Crises And High-Skilled Immigration Policies, Mariana Medina Garciadiego Jan 2010

Give Me Your Engineers, Your Ph.D.S, Yearning To Fund My Welfare State. Fiscal Crises And High-Skilled Immigration Policies, Mariana Medina Garciadiego

All Theses and Dissertations (ETDs)

Points systems, immigration policies in which potential immigrants make an application to enter the country and then are selected on the basis of their skills, age, and occupation, have been proven to be more successful attracting high-skilled immigrants, but very few countries have implemented them. This is particularly paradoxical since high-skilled immigrants are more beneficial in fiscal terms: they are expected to pay more taxes than low skilled immgirants, and not depend heavily on government provided welfare. My core argument is that left of center governments in liberal welfare states implement points systems during a fiscal crisis as a mean …

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The Impact Of Interferon Regulatory Factor 3 On The Immune Response To Herpes Simplex Virus Type I Infection, Vineet Menachery Jan 2010

The Impact Of Interferon Regulatory Factor 3 On The Immune Response To Herpes Simplex Virus Type I Infection, Vineet Menachery

All Theses and Dissertations (ETDs)

The type I interferon: IFN) cascade is critical in control of herpes simplex virus type I: HSV-1) infection and relies on specific recognition molecules to rapidly signal viral infection via interferon regulatory factor-3: IRF-3) -dependent pathways. The absence of these recognition molecules or the loss of IRF-3 would be predicted to render early recognition pathways inoperative and thus impact viral infection. However, previous results had produced contradictory results in terms of the role of IRF-3 during HSV-1 infection. In this study, infected IRF-3-/- immune cells were found to support increased HSV-1 replication compared to control cells. In addition, IRF-3 deficient …

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Exploring Tissue Microstructure In Healthy And Diseased Lung Tissue, Michelle Milne Jan 2010

Exploring Tissue Microstructure In Healthy And Diseased Lung Tissue, Michelle Milne

All Theses and Dissertations (ETDs)

This thesis is divided into two parts. The first part examines diffusion in a number of human lung samples, while the second deals with diffusion in the more simplified environment of a single capillary tube. In the lung study we examine various types of lung samples: healthy and diseased) at a variety of diffusion lengths. Diffusion Magnetic Resonance Imaging: MRI) has been a very useful tool in the study of lungs and lung disease, particularly diffusion MRI using hyperpolarized gases, such as helium or xenon. However, since the polarized gas is difficult to prepare and, once prepared, suffers decay of …

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An Investigation Of The Cognitive And Perceptual Mechanisms Involved In Mania-Proneness, Kimberly Mercer Jan 2010

An Investigation Of The Cognitive And Perceptual Mechanisms Involved In Mania-Proneness, Kimberly Mercer

All Theses and Dissertations (ETDs)

The present research investigates the cognitive and perceptual mechanisms involved in mania-proneness. Building on the work of Depue and colleagues: Depue & Iacono, 1989; Depue & Zald, 1993) and Gray: 1994), which identifies links between the Behavioral Activation System: BAS) and the symptoms observed in mania, this research investigates the hypothesis that people who are prone to mania exhibit cognitive and perceptual biases in information processing when presented with achievement-oriented stimuli both at baseline, and after the receipt of a reward. These hypothesized biases were measured via an affective flanker task, a suboptimal priming task, and a judgment task about …

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Racial Disparities In Hiv Seroprevalence Among Male Street Sex Workers, Larry Morton Jan 2010

Racial Disparities In Hiv Seroprevalence Among Male Street Sex Workers, Larry Morton

All Theses and Dissertations (ETDs)

This dissertation examined whether racial disparities in HIV/AIDS between African American and Caucasian male street sex workers: MSSWs) existed and, if so, what were the possible reasons for these disparities. African American MSSWs were significantly more likely to report being HIV/AIDS-positive. However, when included in binary logistic models, the relationship between HIV risk factors: of syphilis and sexual assault) and HIV status did not significantly vary between African American and Caucasian MSSWs. Mediation of sexual assault and/or syphilis between race and HIV/AIDS could not be tested due to not meeting the assumptions for mediation. African American MSSWs are over twice …

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Essays On Online Browsing And Purchase, Ciju Nair Jan 2010

Essays On Online Browsing And Purchase, Ciju Nair

All Theses and Dissertations (ETDs)

Essay One: Modeling Online Browsing and Purchase of Airline Tickets Online purchases are increasingly becoming a significant portion of total purchases in most product categories. While prior research in marketing has looked at information search and purchase decisions separately, we use a joint framework to study consumers' online browsing and purchase of airline tickets in a unique dataset of household-level dynamic click stream panel data. We use a three-stage model to study: i) the choice of the first website visited,: ii) the duration of browsing on travel websites before making a purchase: iii) the choice of the website where consumers …

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Bodies Of Parchment: Representing The Passion And Reading Manuscripts In Late Medieval England, Sarah Noonan Jan 2010

Bodies Of Parchment: Representing The Passion And Reading Manuscripts In Late Medieval England, Sarah Noonan

All Theses and Dissertations (ETDs)

In a diverse range of late-fourteenth- and fifteenth-century devotional literature, Christ's body is metaphorically related to a book or a document at the moment of his crucifixion. His skin transforms into parchment, whips and scourges become pens, and a steady flow of blood, of ink, covers his body and the written page. And each word written onto his parchment body welcomes sustained study, acting as a potential meditative focal point for the devout reader. Through this metaphor and the accompanying materiality of the texts that include it, medieval authors and audiences could imagine intimately interacting with Christ's body during the …

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The Function And Regulation Of Senescent Stromal-Derived Osteopontin, Ermira Pazolli Jan 2010

The Function And Regulation Of Senescent Stromal-Derived Osteopontin, Ermira Pazolli

All Theses and Dissertations (ETDs)

Our understanding of tumors as complex organs has increased our appreciation for each component of the tumor microenvironment and its respective contribution to tumorigenesis. Fibroblasts found within a tumor actively participate in the growth, progression and metastasis of cancer cells. Senescent fibroblasts, which are permanently arrested yet metabolically active, accumulate in tissue over time where they may promote the proliferation and malignant conversion of preneoplastic cells in older individuals. I have examined the relationship between senescent fibroblasts and preneoplastic keratinocytes and identified the secreted multifunctional protein osteopontin: OPN) as a critical stromal mediating factor. RNAi-directed reduction of stromal OPN leads …

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Genetic Influences On Preterm Birth, Jevon Plunkett Jan 2010

Genetic Influences On Preterm Birth, Jevon Plunkett

All Theses and Dissertations (ETDs)

Preterm birth: PTB) is a leading cause of mortality and disease burden globally; however, determinants of human parturition remain largely uncharacterized, making prediction and prevention of difficult. Genetic studies are one way in which we can attempt to better understand this disorder. We first sought to develop a model for the genetic influences on PTB to facilitate gene discovery. Study of standard measures of familial aggregation, the sibling risk ratio and the sibling-sibling odds ratio, and segregation analyses of gestational age, a quantitative proxy for preterm birth, lend support to a genetic component contributing to birth timing, since preterm deliveries …

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Characterization Of The Role For Nmnat, Kinase Cascades, And Purines In Axonal Degeneration, Craig Press Jan 2010

Characterization Of The Role For Nmnat, Kinase Cascades, And Purines In Axonal Degeneration, Craig Press

All Theses and Dissertations (ETDs)

Axonal degeneration is a prominent feature of many neurological disorders including Parkinson's disease: PD), motor neuron disease, inherited, diabetic, and drug-induced peripheral neuropathies. It is now thought that axonal degeneration is an active process, due in large part to studies of the Wlds mutant mouse, which undergoes delayed Wallerian degeneration in response to axonal injury. Wlds mice have slower disease progression in numerous models of neurodegenerative diseases. The Wlds mutation results in the production of a chimeric protein that containing nicotinamide mononucleotide adenylyltransferase 1: Nmnat1). Increased expression of Nmnat isoforms are sufficient for axonal protection in vitro and in vivo. …

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Phylogenetics And Phylogeography Of Moray Eels (Muraenidae), Joshua Reece Jan 2010

Phylogenetics And Phylogeography Of Moray Eels (Muraenidae), Joshua Reece

All Theses and Dissertations (ETDs)

This dissertation describes the evolutionary history of Moray eels: Muraenidae). Moray eels are apex predators on coral reefs around the world, but they are not well studied because of their cryptic habitats and occasionally aggressive behaviors. I provide the first molecular phylogeny of moray eels with widespread taxonomic and geographic coverage, including 44 species representing two subfamilies, eight genera, and all tropical ocean basins. Phylogenetic relationships among these taxa are estimated from portions of mitochondrial loci cytochrome b and cytochrome oxidase subunit 1, and portions of the nuclear loci RAG-1 and RAG-2. I test four sets of contrasting phylogenetic hypotheses …

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Reducing False Hearing In The Elderly: Variability Training In Meta-Audition, Chad Rogers Jan 2010

Reducing False Hearing In The Elderly: Variability Training In Meta-Audition, Chad Rogers

All Theses and Dissertations (ETDs)

A large body of work supports the conclusion that older adults derive more benefit than young adults from the addition of contextual information in speech perception: Hutchinson, 1989; Pichora-Fuller, Schneider, & Daneman, 1995; Pichora-Fuller, 2008). More recent work by Rogers, Jacoby, and Sommers: in prep) showed that when contextual information and sensory information favored competing responses, older adults were more likely to falsely "hear" the word favored by context. The current research describes two experiments that attempt to mitigate this age-related increase on contextual reliance. Experiment 1 assessed whether the effects of context in Rogers, Jacoby, & Sommers: in prep) …

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A Processing Approach To The Working Memory/Long-Term Memory Distinction: Evidence From A Levels-Of-Processing Span Task, Nathan Rose Jan 2010

A Processing Approach To The Working Memory/Long-Term Memory Distinction: Evidence From A Levels-Of-Processing Span Task, Nathan Rose

All Theses and Dissertations (ETDs)

Recent studies have raised questions about the extent to which working memory: WM) is dissociable from secondary or long-term memory: LTM). Although many similarities may exist between immediate retrieval on WM span tasks and delayed retrieval on LTM tests, important differences exist as well. To illustrate this point, Craik and Tulving's classic levels-of-processing paradigm was adapted for use in a WM span task: Participants made visual, phonological, or semantic judgments about 33 words using the same stimuli and instructions as Craik and Tulving: 1975), but were to recall words immediately after every 3 or 8 words: rather than after all …

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The Role Of The Clock Gene Bmal1 In Female Fertility And Parturition, Christine Ratajczak Jan 2010

The Role Of The Clock Gene Bmal1 In Female Fertility And Parturition, Christine Ratajczak

All Theses and Dissertations (ETDs)

Successful reproduction is essential for survival of species. For humans, reproductive problems can cause large emotional and medical burdens. Evidence in both humans and rodents indicates that circadian rhythmicity is important for supporting reproductive function. A molecular clock orchestrates circadian rhythmicity. Impairment in fertility and parturition are observed in female mice expressing a mutant form of Clock, suggesting critical roles for clock genes in reproduction. Since the clock gene Bmal1, but not Clock, is necessary for the generation of circadian rhythmicity, exploring the role of Bmal1 in reproduction may yield a better understanding of the importance of the molecular clock …

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Conservation Of The Intracellular Bacterial Community Pathogenic Pathway In Urinary Tract Infection, David Rosen Jan 2010

Conservation Of The Intracellular Bacterial Community Pathogenic Pathway In Urinary Tract Infection, David Rosen

All Theses and Dissertations (ETDs)

Urinary tract infections: UTIs) affect 13 million women annually in the United States. Uropathogenic Escherichia coli: UPEC) is the predominant etiologic agent of UTI; however, several other uropathogens, including Klebsiella pneumoniae, are also significant causative agents. 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, adhesive fimbriae, 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 proceed to infect other host urothelial cells. This work …

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