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The Genetic Architecture And Evolution Of Brain Cortical Folding In A Pedigreed Primate Population, Elizabeth Grace Atkinson

Arts & Sciences Electronic Theses and Dissertations

Elevated neurological faculty, related to the dramatic increase in brain volume, is a hallmark of the primates. Cognitive capacity, the processing power and speed of the brain, is directly related to the number of neurons in the cerebral cortex and the connectivity network underlying information processing in the brain. Increased cortical folding (gyrification) allows for more neurons to be contained within the volume of the braincase and the arrangement of folds and ridges across the cerebral cortex is an indication of the underlying neural network connecting regions. The goal of this dissertation is to develop a better understanding of the …

The Enhancing Effect Of Retrieval On Subsequent Encoding: Understanding Test-Potentiated Learning, Kathleen Marie Arnold

Arts & Sciences Electronic Theses and Dissertations

Retrieval practice directly enhances later memory of tested material, a robust effect known as the testing effect (Roediger & Karpicke, 2006b). Numerous experiments have provided support for this effect. However, another important effect of retrieval practice has received far less attention. Retrieval practice can also indirectly enhance learning by potentiating subsequent encoding of tested material, an effect known as test-potentiated learning (Izawa, 1966). Although introduced over four decades ago, little is known about how and when tests enhance subsequent encoding, information that has both practical and theoretical importance. The aim of this dissertation was to enhance understanding of test-potentiated learning …

Type 1 Diabetes And The Male Reproductive Axis, Erica Schoeller

Arts & Sciences Electronic Theses and Dissertations

Glucose regulation is important in both spermatogenesis as well as mature sperm function. The impact of diabetes on sperm function is becoming increasingly clear, though much work is still needed to elucidate the mechanism by which diabetes impairs spermatogenesis. Diabetes causes disruptions in the hypothalamic pituitary gonadal (HPG) axis, the regulatory system that controls reproduction. The HPG axis functions by secreting GnRH pulses from the hypothalamus, which bind to receptors on the pituitary and cause secretion of follicle stimulating hormone and luteinizing hormone, which then bind to receptors in the testes and facilitate spermatogenesis. Type 1 diabetes can severely impact …

Structural And Functional Study Of The Diheme Cytochrome C Subunit Of The Cytochrome Bc Complex In Heliobacterium Modesticaldum, Hair Yue

Arts & Sciences Electronic Theses and Dissertations

This dissertation is focused on the structural and functional study of the unique diheme cytochrome c subunit of the cytochrome bc complex in H. modesticaldum, and its application in determining the stoichiometry between H. modesticaldum's cytochrome bc complex and its reaction center. Heliobacterium modesticaldum is a gram positive, anaerobic, anoxygenic photoheterotrophic bacterium. Its cytochrome bc complex (Rieske/cyt b complex) has some similarities to cytochrome b6f complexes from cyanobacteria and chloroplasts, and also shares some characteristics of typical bacterial cytochrome bc1 complexes. One of the unique features of the heliobacterial cytochrome bc complex is the presence of a diheme cytochrome c …

Quantification Of Conformational Heterogeneity And Its Role In Protein Aggregation And Unfolding, Nicholas J. Lyle

Arts & Sciences Electronic Theses and Dissertations

Proteins can exhibit significant conformational heterogeneity either under denaturing conditions or in aqueous solutions. The latter is true for a class of proteins whose sequences predispose them to form heterogeneous ensembles of conformations. Characterization of conformational heterogeneity in a protein ensemble requires the quantification of the amplitudes of spontaneous fluctuations in conjunction with information regarding coarse grain measures that report on the average sizes, shapes, and densities. This often demands multiplexed experimental approaches whose readouts are interpreted or annotated using ensembles drawn from atomistic or coarse grain computational simulations. Efforts to characterize conformational heterogeneity contribute directly to our understanding of …

Biological Applications Of Extraordinary Electroconductance And Photovoltaic Effects In Inverse Extraordinary Optoconductance, Lauren C. Tran

Arts & Sciences Electronic Theses and Dissertations

The Extraordinary Electroconductance (EEC) sensor has been previously demonstrated to have an electric field sensitivity of 3.05V/cm in a mesoscopic-scale structure fabricated at the center of a parallel plate capacitor. In this thesis, we demonstrate the first successful application of EEC sensors as electrochemical detectors of protein binding and biological molecule concentration. Using the avidin derivative, captavidin, in complex with the vitamin biotin, the change in four-point measured resistance with fluid protein concentration of bare EEC sensors was shown to increase by a factor of four in the presence of biomolecular binding as compared to baseline. Calculations for approximate field …

Post-Translational Regulation Of Fas-Mediated Pparα Activation, Anne Patricia Louise Jensen-Urstad

Arts & Sciences Electronic Theses and Dissertations

The liver is a central organ to whole-body metabolism and mediates many of the adaptive responses to changes in nutrient availability, such that the appropriate energy sources are used and blood glucose levels maintained, whether directly after a meal or after a twelve-hour fast. The adaptive responses to fasting in liver are largely mediated by the nuclear receptor peroxisome proliferator-activated receptor α, or PPARα.

PPARα can be activated by a de novo synthesized lipid ligand—16:0/18:1- glycerophosphocholine (16:0/18:1-GPC)—the synthesis of which is dependent on fatty acid synthase (FAS), but little is known about the regulation of this pathway. My thesis focused …

Assessing Optic Neuritis In A Mouse Model Of Multiple Sclerosis With Diffusion Mr Imaging, Chia-Wen Chiang

Arts & Sciences Electronic Theses and Dissertations

Optic neuritis (ON) is an early manifestation in patients of multiple sclerosis (MS), typically resulting in visual dysfunction. The inflammatory demyelination of the optic nerve in ON closely resembles pathologies of the rest of central nervous system (CNS) white matter in MS. Since accumulated axonal degeneration in MS was considered as the potential cause leading to permanent disability, correlating optic nerve pathology and visual function in ON could be a model system to investigate the relationship between functional outcome and neuropathology. It may also present a new way to reflect the disease progression in MS. Various MR techniques have been …

The Natural Variants Of The Streptococcus Nad+-Glycohydrolase Spn Modulate Divergent Host Cell Signaling Pathways And Death, Sukantha Chandrasekaran

Arts & Sciences Electronic Theses and Dissertations

Streptococcus pyogenes has an arsenal of virulence factors that promote its ability to cause a broad range of diseases and fight host defenses. One of these factors is the S. pyogenes NAD+-glycohydrolase (SPN), which is secreted from the bacterial cell and translocated into the host cell cytosol where it contributes to cell death. Every strain examined to date has SPN and recent studies suggest that SPN is continuing to evolve diverging into two variants that correlate with tissue tropism, one of which lacks the signature NADase activity. SPN's roles in both cytotoxicity and niche selection are unknown. To gain insight …

Various Geometric Aspects Of Condensed Matter Physics, Zhenyu Zhou

Arts & Sciences Electronic Theses and Dissertations

Geometric aspect of condensed matter has arouse a lot of interests in recent years. The idea of Berry phase is highly appreciated in various systems. We explored the geometric features of two specific electron systems, fractional quantum Hall (FQH) states and d-wave superconducting states. For FQH states, we propose a two body operator which generates the geometric change of Laughlin state in the guiding center degrees of freedom on torus. This operator therefore generates the adiabatic evolution between Laughlin states on regular tori and the quasi-one-dimensional thin torus limit. For d-wave superconducting model, we study the local and topological features …

Development Of Polarizable Force Field Models For Transition Metal Ions, Jin Yu Xiang

Arts & Sciences Electronic Theses and Dissertations

This dissertation focuses on the development of polarizable molecular mechanics (MM) force field models for the third-row transition metal (TM) ions. These TM ions perform important structural and chemical functions in a wide range of organic and biological environments because of the unique properties of the 3d orbitals. Being able study these systems in silico can provide a tremendous amount of information that is difficult to obtain through experiments. However, the standard treatment of ions in traditional MM models has shown to be insufficient for describing the d-shell electronic effects. In this work, empirical models for TM electronic effects are …

A Study On The Structure And Photodetachment Dynamics Of Copper Based Molecular Anions Using Photoelectron Spectroscopy, Nicholas Stephen Holtgrewe

Arts & Sciences Electronic Theses and Dissertations

This dissertation represents a study of the effects of electron molecule interactions in the detachment and dissociation dynamics of copper based molecular anions. Results are presented on the photodetachment of small copper oxide CuO_n⁻ (n = 1, 2) and copper fluoride CuF _n⁻ (n = 1, 2) molecular anions. Effects of different resonances are explored using the photoelectron angular distributions (PADs) and the relative intensity variations in vibrational channel cross sections. The specific resonances studied include dipole bound resonances, in which the electric dipole moment of the neutral molecule captures the outgoing electron, and electronic Feshbach resonances, …

Dysfunctional Gene Regulation Of The Meiotic Program In An Interspecific Yeast Hybrid, Devjanee Swain Lenz

Arts & Sciences Electronic Theses and Dissertations

Speciation, the evolutionary process by which species arise, is a fundamental biological concept. One of the major goals of evolutionary genetics is to understand the genetic basis of reproductive isolation (RI), a collection of barriers that prevents two species from forming viable or fertile hybrids. Given the lack of viable or fertile hybrid progeny, identifying genes that impact RI as well as their functions has been difficult. Thus we lack a view of the total genetic contribution to RI. Recently the budding yeast Saccharomyces has served as an evolutionary model, as abundant sequence, expression, and phenotypic data exist for the …

An Investigation Into Peripersonal Space Representations In Older Adults, Emily K. Bloesch

Arts & Sciences Electronic Theses and Dissertations

Peripersonal space is the space immediately surrounding one's body. This space is believed to have a unique representation in order to facilitate successful interaction with the surrounding environment. Supporting this theory, there are consistent findings of changes in cognition within as compared to beyond peripersonal space, including differences in visual attention and perception. However, research on peripersonal space in healthy populations has largely focused on young adults. Representations of peripersonal space take place in multimodal brain regions, areas that show structural and functional changes during senescence. Because of this, there is reason to suspect that older adults represent peripersonal space …

Winning The Waiting Game: Senatorial Delay In Executive Nominations, Ian Ostrander

Arts & Sciences Electronic Theses and Dissertations

Presidents have a strong incentive to control executive agencies through the nomination of like-minded and responsive individuals to leadership posts. The Senate, however, must provide its advice and consent for appointments to these key positions. While most nominees are successfully confirmed, this success rate tends to mask wide variation in the length of time it takes the Senate to make a decision. Delay of critical nominees can influence the character of an agency while hampering the policy ambitions of a president. In this way the power to delay can be as important as the power to reject a nominee. Building …

Photosynthetic Chromophore Analogs And Biohybrid Antenna For Light Harvesting, Joseph William Springer

Arts & Sciences Electronic Theses and Dissertations

Photosynthetic chromophore analogs are studied, starting with simplified structures and systematically building complexity to elucidate overarching design principles. The general goals are to achieve an artificial light-harvesting system that exhibits broad spectral coverage, including extension well into the photon rich red and near-infrared portions of the solar spectrum. For example, the spectral properties of chlorophylls are primarily a consequence of the 13¹-oxophorbine base macrocycle, with further tuning provided by the dramatic difference in auxochromic effects of a given substituent at the 7- versus 3-position, consistent with Gouterman's four-orbital model.

While light-harvesting antennas in photosynthetic bacteria generally have near-quantitative …

The Uropathogenic Escherichia Coli Effector Ybcl Modulates The Innate Immune Response In The Urinary Tract, Megan Elizabeth Lau

Arts & Sciences Electronic Theses and Dissertations

Uropathogenic Escherichia coli (UPEC) are the primary etiology of urinary tract infections (UTIs), one of the most common bacterial infections afflicting the human population. While UPEC cause disease throughout the urinary tract, bladder infection, or cystitis, is most prevalent. A key aspect of UPEC pathogenesis in the bladder is the modulation of the host inflammatory response. At acute time points, UPEC delay the arrival of immune cells, such as neutrophils, to the bladder. The lack of neutrophils in the bladder lumen enables UPEC to replicate freely in the urine and invade the bladder epithelium, a requirement for bacterial persistence, in …

Essays On Dynamic Pricing, Koray Cosguner

Arts & Sciences Electronic Theses and Dissertations

In empirical marketing literature, it is well documented that most of the frequently consumed packaged good categories are governed by inertia that is the phenomenon of consumers often repeat-purchasing the same brand on successive purchase occasions. Under such inertial behavior, market-level demand becomes to be correlated over time, i.e., if the demand of a brand is high in a given week, it is likely to remain high in the ensuing weeks. The pricing implication of such inertia is, for instance, a current retail price cut for a brand not only increase its demand in the current week, but also increase …

Urine Trouble: A Molecular And Anatomical Examination Of Bladder Pain, Lara Wiley Crock

Arts & Sciences Electronic Theses and Dissertations

Interstitial cystitis or painful bladder syndrome (IC/PBS) is a chronic pain syndrome affecting 3-6% of women in the US. Some evidence suggests urothelial injury may cause some cases of IC/PBS. To examine how urothelial injury modulates bladder pain, three injury models were used: Infection with uropathogenic Escherichia coli (UPEC, inflammatory), Protamine sulfate (PS, non-inflammatory chemical), and lipopolysaccharide (LPS, non-infectious and inflammatory) treatment. Surprisingly, injury with PS decreased, while UPEC alone increased the pain response to bladder distention. These data suggest that changes in the urothelium may modulate some forms of IC/PBS. However, in most cases, patients with IC/PBS have no …

Essays On Quantitative Methods For Consequences Of Political Institutions, Tsung-Han Tsai

Arts & Sciences Electronic Theses and Dissertations

In this dissertation, I develop and apply sophisticated Bayesian models to the analysis of institutional effects on electoral and legislative behavior in the policy making process. Leveraging the flexibility of Bayesian methods for statistical modeling, I deal with several methodological problems encountered by political scientists, and social scientists in general, in some established research agenda. This dissertation shows the improvement of the ability to evaluate the success of conflicting theories when these methodological issues are properly dealt with.

The consequences of political institutions are investigated at three different levels in this dissertation: countries, political parties, and individual legislators. First of …

The Development Of The Architectural Styles Of New France, Jennifer Brazier

Arts & Sciences Electronic Theses and Dissertations

In this paper, I will explore the impact of multiple cultures, climate and available resources on the architecture of New France. I will begin with early settlements of Nova Scotia and Québec, and follow the Mississippi River down to New Orleans. These early French settlements in the new world struggled to retain their identities in the face of English and Spanish control. Although Canadian territories were affected by English possession, they were the most successful in retaining a French influence. Even today, French is the official language of Québec, and the Catholic religion remains an important part of everyday life …