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Washington University in St. Louis

Theses/Dissertations

2018

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Full-Text Articles in Life Sciences

Singing As A Therapeutic Technique To Improve Gait For People With Parkinson Disease, Elinor Harrison Dec 2018

Singing As A Therapeutic Technique To Improve Gait For People With Parkinson Disease, Elinor Harrison

Arts & Sciences Electronic Theses and Dissertations

Abstract of the Dissertation

Singing as a Therapeutic Technique to

Improve Gait for People with Parkinson Disease

by

Elinor Clare Harrison

Doctor of Philosophy in Movement Science

Neurosciences

Washington University in St. Louis, 2018

Professor Gammon Earhart, Chair

Gait impairment is common in older adults and even more prevalent for people with Parkinson disease (PD). Gait dysfunction is often characterized by reductions in speed, step frequency, and step length. In addition, decreased ability to regulate step length and step frequency may contribute to increased gait variability, making walking less stable and increasing risk for falls. As gait deficits are often …


Freezing Of Gait: Mechanisms, Mechanics, And Management, Peter S. Myers Dec 2018

Freezing Of Gait: Mechanisms, Mechanics, And Management, Peter S. Myers

Arts & Sciences Electronic Theses and Dissertations

Parkinson disease (PD) is a neurodegenerative disease with multiple motor and non-motor symptoms, including postural instability, gait impairments, and cognitive deficits. More than 50% of individuals with PD experience a symptom called freezing of gait (FOG), described as a transient inability to take another step forward. Individuals with PD who experience FOG (freezers) have further postural, gait, and cognitive impairments compared to individuals with PD without FOG (non-freezers). While degeneration of the dopaminergic neurons in the substantia nigra is accepted as the primary etiology of the disease, research shows that the disease has a global impact on the brain, accounting …


Grammar And Variation: Understanding How Cis-Regulatory Information Is Encoded In Mammalian Genomes, Dana Michele King Dec 2018

Grammar And Variation: Understanding How Cis-Regulatory Information Is Encoded In Mammalian Genomes, Dana Michele King

Arts & Sciences Electronic Theses and Dissertations

Understanding how genotype leads to phenotype is key to understand both the development and dysfunction of complex organisms. In the context of regulating the gene expression patterns that contribute to cell identity and function, the goal of my thesis research is to how changes in genome sequence may impact impact gene expression by determining how sequence features contribute to regulatory potential. To accomplish this goal, I first leveraged the key regulatory role of pluripotency transcription factors (TFs) in mouse embryonic stem cells (mESCs) and tested synthetically generated and genomic identified combinations of binding site for four TFs, OCT4, SOX2, KLF4, …


Kcnq1/Kcne1 Interaction In The Cardiac Iks Channel And Its Physiological Consequences, Jiajing Xu Dec 2018

Kcnq1/Kcne1 Interaction In The Cardiac Iks Channel And Its Physiological Consequences, Jiajing Xu

McKelvey School of Engineering Theses & Dissertations

Dynamic conformational changes of ion channel proteins during activation gating determine their function as carriers of current. The relationship between these molecular movements and channel function over the physiological timescale of the action potential (AP) has not been fully established due to limitations of existing techniques. We constructed a library of possible cardiac IKs protein conformations and applied a combination of protein segmentation and energy linearization to study this relationship computationally. Simulations reproduced the effects of the beta-subunit (KCNE1) on the alpha-subunit (KCNQ1) dynamics and function, observed in experiments. Mechanistically, KCNE1 increased the probability of “visiting” conducting pore conformations on …


The Splice Is Not Right: Splice-Site-Creating Mutations In Cancer Genomes, Reyka Glencora Jayasinghe Dec 2018

The Splice Is Not Right: Splice-Site-Creating Mutations In Cancer Genomes, Reyka Glencora Jayasinghe

Arts & Sciences Electronic Theses and Dissertations

Accurate interpretation of cancer mutations in individual tumors is a prerequisite for precision medicine. Large-scale sequencing studies, such as The Cancer Genome Atlas (TCGA) project, have worked to address the functional consequences of genomic mutations, with the larger goal of determining the underlying mechanisms of cancer initiation and progression. Many studies have focused on characterizing non-synonymous somatic mutations that alter amino acid sequence, as well as splice disrupting mutations at splice donors and acceptors. Current annotation methods typically classify mutations as disruptors of splicing if they fall on the consensus intronic dinucleotide splice donor, GT, the splice acceptor, AG. Splice …


Neural Mechanisms Of Drosophila Circadian Rhythms, Xitong Liang Dec 2018

Neural Mechanisms Of Drosophila Circadian Rhythms, Xitong Liang

Arts & Sciences Electronic Theses and Dissertations

Animals show circadian rhythms in a variety of physiological functions and behaviors. In Drosophila melanogaster, behavioral rhythms are driven by circadian clock genes that are oscillating in ~150 circadian pacemaker neurons. To explain how circadian neurons encode time and regulate different behavioral rhythms, I performed 24-hour in vivo whole-brain calcium imaging using light-sheet microscopy. First, I found that different groups of circadian neurons show circadian rhythms in spontaneous neural activity with diverse phases. The neural activity phases of the M and E pacemaker groups, which are associated with the morning and evening locomotor activities respectively, occur ~4 hours before their …


Combining Footprinting Mass Spectrometry And Molecular Dynamics Simulation For Structural Studies In Membrane Proteins, Fengbo Zhou Dec 2018

Combining Footprinting Mass Spectrometry And Molecular Dynamics Simulation For Structural Studies In Membrane Proteins, Fengbo Zhou

Arts & Sciences Electronic Theses and Dissertations

Membrane proteins are essential in many cellular processes and represent ~60% of all current drug targets. Due to technical limits, membrane proteins of various types were not studied extensively in the past and the biochemistry and functionality of them remain unclear. The structural biology methodologies require pure isolated protein samples for us to resolve their structure and study their biochemical functions. For such in vitro studies, however, membrane proteins often become unstable when isolated from their native lipid bilayer environment. To overcome the challenge, I employed a novel methodology of solubilizing membrane proteins in solution without detergent. I reconstituted ferroportin, …


The Essential Roles Of The Chromatin Factor Gon4l In Heart Development, Terin Elise Budine Dec 2018

The Essential Roles Of The Chromatin Factor Gon4l In Heart Development, Terin Elise Budine

Arts & Sciences Electronic Theses and Dissertations

Heart development and the genetic pathways underlying it are highly conserved among vertebrates. During heart development, an embryo must induce mesoderm formation, pattern the mesoderm, specify cardiomyocytes, increase the population of cardiomyocytes through proliferation, and pattern the cardiac chambers. It is becoming increasingly clear that chromatin modifications help mediate the complex processes of heart development by providing spatiotemporal regulation of gene expression. My thesis work focuses on characterizing functions of the chromatin factor Gonad-4-like (Gon4l), encoded by the gene ugly duckling (udu), in zebrafish heart development. Previous works established a requirement for Gon4l in the formation of many mesoderm derivatives …


Protein Structure-Guided Approaches To Identify Functional Mutations In Cancer, Sohini Sengupta Dec 2018

Protein Structure-Guided Approaches To Identify Functional Mutations In Cancer, Sohini Sengupta

Arts & Sciences Electronic Theses and Dissertations

Distinguishing driver mutations from passenger mutations within tumor cells continues to be a major challenge in cancer genomics. Many computational tools have been developed to address this challenge; however, they rely heavily on primary protein sequence context and frequency/mutation rate. Rare driver mutations not found in many cancer patients may be missed with these traditional approaches. Additionally, the structural context of mutations on tertiary/quaternary protein structures is not taken into account and may play a more prominent role in determining phenotype and function. This dissertation first presents a novel computational tool called HotSpot3D, which identifies regions of protein structures that …


Sequence Analysis Methods For The Design Of Cancer Vaccines That Target Tumor-Specific Mutant Antigens (Neoantigens), Jasreet Hundal Dec 2018

Sequence Analysis Methods For The Design Of Cancer Vaccines That Target Tumor-Specific Mutant Antigens (Neoantigens), Jasreet Hundal

Arts & Sciences Electronic Theses and Dissertations

The human adaptive immune system is programmed to distinguish between self and non-self proteins and if trained to recognize markers unique to a cancer, it may be possible to stimulate the selective destruction of cancer cells. Therapeutic cancer vaccines aim to boost the immune system by selectively increasing the population of T cells specifically targeted to the tumor-unique antigens, thereby initiating cancer cell death.. In the past, this approach has primarily focused on targeted selection of ‘shared’ tumor antigens, found across many patients. The advent of massively parallel sequencing and specialized analytical approaches has enabled more efficient characterization of tumor-specific …


A Mouse Model Of Börjeson-Forssman-Lehmann Syndrome Reveals A Potential Link With Autism Spectrum Disorder, Cheng Cheng Dec 2018

A Mouse Model Of Börjeson-Forssman-Lehmann Syndrome Reveals A Potential Link With Autism Spectrum Disorder, Cheng Cheng

Arts & Sciences Electronic Theses and Dissertations

ABSTRACT OF THE DISSERTATION

A Mouse Model of Börjeson-Forssman-Lehmann Syndrome reveals a potential link with Autism Spectrum Disorder

By

Cheng Cheng

Doctor of Philosophy in Biology and Biomedical Sciences

Developmental, Regenerative and Stem Cell Biology

Washington University in St. Louis, 2018

Dr. Azad Bonni, Chair

Intellectual disability (ID) is a prevalent neurodevelopmental disorder that affects 1% to 3% of the general population. ID is characterized by developmental deficiencies in cognitive function and adaptive behaviors. Lacking effective treatments, ID currently presents an immense burden to affected families and the economy. Therefore, there is an urgent need to elucidate the pathogenesis of …


Mechanistic Characterization Of Resistome And Microbiome Dynamics Across Diverse Microbial Habitats, Andrew John Gasparrini Dec 2018

Mechanistic Characterization Of Resistome And Microbiome Dynamics Across Diverse Microbial Habitats, Andrew John Gasparrini

Arts & Sciences Electronic Theses and Dissertations

Increasing antibiotic resistance in pathogens is a serious public health challenge, with over two million antibiotic resistant infections in the United States leading to at least 23,000 deaths and an estimated $55 billion in excess healthcare and societal costs. Antibiotic resistance has risen steadily in both pathogenic and benign bacteria since antibiotics’ introduction to agriculture and medicine 70 years ago. A dramatic reduction in the number of antibiotics approved for human use has accompanied this rise in antibiotic resistance, leading to the alarming prospect of a post-antibiotic era. Understanding the evolutionary origins, genetic contexts, and molecular mechanisms of antibiotic resistance …


Genetic Basis Of Thermal Divergence In Saccharomyces Species, Xueying C. Li Dec 2018

Genetic Basis Of Thermal Divergence In Saccharomyces Species, Xueying C. Li

Arts & Sciences Electronic Theses and Dissertations

The genetic architecture of phenotypic divergence is a central question in evolutionary biology. Genetic architecture is impacted by whether evolution occurs through accumulation of many small-effect or a few large-effect changes, the relative contribution of coding and cis-regulatory changes, and the prevalence of epistatic effects. Our empirical understanding of the genetic basis of evolutionary change remains incomplete, largely because reproductive barriers limit genetic analysis to those phenotypes that distinguish closely related species. In this dissertation, I use hybrid genetic analysis to examine the basis of thermal divergence between two post-zygotically isolated species, Saccharomyces cerevisiae and S. uvarum. S. cerevisiae is …


The Role Of Fibrillin-1 In Eye Development And Disease, Wendell Brooks Jones Dec 2018

The Role Of Fibrillin-1 In Eye Development And Disease, Wendell Brooks Jones

Arts & Sciences Electronic Theses and Dissertations

The ciliary zonule of the human eye consists of a circumferential array of fibers that connect the ocular lens to the nonpigmented ciliary epithelium (NPCE) located at the inner wall of the eye. Zonular fibers consist of bundles of beaded filaments called microfibrils. Microfibrils are major structural elements of the extracellular matrix and are present in pure form in the ciliary zonule. Microfibrils are composed principally of fibrillin-1 (FBN-1); a large extracellular matrix glycoprotein. In humans, mutations in FBN1 underlie Marfan syndrome; a pleiotropic connective tissue disorder that profoundly affects the eye. Ocular manifestations include ectopia lentis (dislocated lenses), cataracts, …


A Recombinant Virus And Reporter Mouse System To Study Chronic Chikungunya Virus Pathogenesis, Alissa Roxanne Young Dec 2018

A Recombinant Virus And Reporter Mouse System To Study Chronic Chikungunya Virus Pathogenesis, Alissa Roxanne Young

Arts & Sciences Electronic Theses and Dissertations

Chikungunya virus (CHIKV) is an arthritogenic alphavirus that during acute disease causes fever as well as severe joint and muscle pain. Chronic joint and muscle pain persists in a significant subset of patients, yet we still have a poor understanding of what drives this chronic disease. While replicating virus has not been detected in the joints of patients with chronic arthritis or in various animal models at chronic time points, persistent viral RNA can be detected for months after acute infection.

To identify the cells that could be contributing to chronic CHIKV pathogenesis, we developed recombinant viruses that express Cre …


The Role Of Apolipoprotein E In Regulating Tau Pathogenesis And Neurodegeneration In A Tauopathy Mouse Model, Yang Shi Dec 2018

The Role Of Apolipoprotein E In Regulating Tau Pathogenesis And Neurodegeneration In A Tauopathy Mouse Model, Yang Shi

Arts & Sciences Electronic Theses and Dissertations

APOE4 is the strongest genetic risk factor for late-onset Alzheimer's disease (AD). APOE4 increases brain amyloid-β (Aβ) pathology relative to other APOE isoforms. However, whether APOE independently influences tau pathology, the other pathological hallmark of AD and other tauopathies, or tau-mediated neurodegeneration, is not clear. By generating P301S tau transgenic mice on either a human APOE knock in (KI) or APOE knockout (KO) background, we show that the presence of human APOE, regardless of APOE isoforms, leads to various degrees of brain atrophy in 9-month old P301S mice, whereas APOE ablation strongly protects against neurodegeneration. In particular, P301S/E4 mice develop …


Fast Objective Coupled Planar Illumination Microscopy, Cody Jonathan Greer Dec 2018

Fast Objective Coupled Planar Illumination Microscopy, Cody Jonathan Greer

Arts & Sciences Electronic Theses and Dissertations

Among optical imaging techniques light sheet fluorescence microscopy stands out as one of the most attractive for capturing high-speed biological dynamics unfolding in three dimensions. The technique is potentially millions of times faster than point-scanning techniques such as two-photon microscopy. This potential is especially poignant for neuroscience applications due to the fact that interactions between neurons transpire over mere milliseconds within tissue volumes spanning hundreds of cubic microns. However current-generation light sheet microscopes are limited by volume scanning rate and/or camera frame rate. We begin by reviewing the optical principles underlying light sheet fluorescence microscopy and the origin of these …


A Tail Of Two Pancancer Projects: Somatic Variant Identification And Driver Gene Discovery Using Tcga, Matthew Hawkins Bailey Dec 2018

A Tail Of Two Pancancer Projects: Somatic Variant Identification And Driver Gene Discovery Using Tcga, Matthew Hawkins Bailey

Arts & Sciences Electronic Theses and Dissertations

The implementation of next-generation genomic sequencing has exploded over the past dozen years. Large consortia, such as The Cancer Genome Atlas (TCGA); the International Cancer Genetics Consortium (ICGC); and the Pediatric Cancer Genome Projects (PCGP), made great strides in democratizing big data for the scientific community. These data sets provide a rich resource to build tools for somatic variant discovery and exploratory analysis. Public repositories hold the answer to many novel biological and clinical revelations i.e., the discovery of complex indels, splice creating mutations, alternative super enhancer binding sites, machine learning models to predict mutation impact, and cancer subtype classification …


Acetylation Profiles Of Histone And Non-Histone Proteins In Breast Cancer, Alla Karpova Dec 2018

Acetylation Profiles Of Histone And Non-Histone Proteins In Breast Cancer, Alla Karpova

McKelvey School of Engineering Theses & Dissertations

This study evaluates the impact of protein acetylation on breast cancer gene expression and the regulation of metabolism. Acetylation is the second abundant post-translational modification after phosphorylation, regulating protein activity and function. The alterations in acetylation of both histone and non-histone proteins is known to be related to many human diseases, including cancer. Acetylation and deacetylation of histones is closely associated with the regulation of gene expression, while acetylation of non-histone proteins may have a broad effect on major cellular processes, such as proliferation, metabolism, cell cycle and apoptosis, imbalanced regulation of which is essential for cancer development. Therefore, it’s …


Effects Of Resistance Exercise On Postprandial Metabolism In Obese Men With Prediabetes, Adam Bittel Aug 2018

Effects Of Resistance Exercise On Postprandial Metabolism In Obese Men With Prediabetes, Adam Bittel

Arts & Sciences Electronic Theses and Dissertations

Prediabetes is a metabolic condition defined by elevated fasting (impaired fasting glucose (IFG)) and/or postprandial (impaired glucose tolerance (IGT)) glucose. Prediabetes affects nearly 86 million adults in the United States, with most (up to 70%) progressing to type 2 diabetes within as little as one year. Recent studies have indicated that elevated post-prandial glycemia and hypertriglyceridemia are early indicators of prediabetes, and are major risk factors for complications of prediabetes, including cardiovascular disease (CVD), stroke, elevated blood pressure, and obesity. Resistance exercise is a central component of exercise recommendations for individuals with type 2 diabetes and prediabetes, but the effect …


Development And Evaluation Of Biocompatible Engineered Nanoparticles For Use In Ophthalmology, Bedia Begum Karakocak Aug 2018

Development And Evaluation Of Biocompatible Engineered Nanoparticles For Use In Ophthalmology, Bedia Begum Karakocak

McKelvey School of Engineering Theses & Dissertations

The synthesis and design of biocompatible nanoparticles for targeted drug delivery and bioimaging requires knowledge of both their potential toxicity and their transport. For both practical and ethical reasons, evaluating exposure via cell studies is a logical precursor to in vivo tests. As a step towards clinical trials, this work extensively investigated the toxicity of gold nanoparticles (Au NPs) and carbon dot (CD) nanoparticles as a prelude to their in vivo application, focusing specifically on ocular cells. As a further step, it also evaluated their whole-body transport in mice. The research pursued two approaches in assessing the toxicity of engineered …


The Role Of Membrane Excitability In Insulin Regulation, Christopher Howard Emfinger Aug 2018

The Role Of Membrane Excitability In Insulin Regulation, Christopher Howard Emfinger

Arts & Sciences Electronic Theses and Dissertations

In mammals, ATP-sensitive K+ (KATP) channels are essential regulators of insulin secretion from pancreatic islet [beta]-cells, illustrated by the finding that gain-of-function mutations in KATP channels (KATP-GOF) cause neonatal diabetes mellitus (NDM). However, variability in symptom severity and effectiveness of treatment is seen in NDM, even for those with the same mutation and in the same family. Short-term treatment of mice expressing KATP-GOF mutations in [beta]-cells (KATP-GOF mice) with the KATP blocker glibenclamide during disease onset results in two outcomes: one subset becomes severely diabetic (non-remitters), whereas the other subset remains below the glucose levels at which significant side effects …


Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler Aug 2018

Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler

McKelvey School of Engineering Theses & Dissertations

The brain connects to, modulates, and receives information from every organ in the body. As such, brain-computer interfaces (BCIs) have vast potential for diagnostics, medical therapies, and even augmentation or enhancement of normal functions. BCIs provide a means to explore the furthest corners of what it means to think, to feel, and to act—to experience the world and to be who you are. This work focuses on the development of a chronic bi-directional BCI for sensorimotor restoration through the use of separable frequency bands for recording motor intent and providing sensory feedback via electrocortical stimulation. Epidural cortical surface electrodes are …


A Mechanism Of Antimicrobial Resistance And A Mitigation Strategy, Christopher Bulow Aug 2018

A Mechanism Of Antimicrobial Resistance And A Mitigation Strategy, Christopher Bulow

Arts & Sciences Electronic Theses and Dissertations

ABSTRACT OF THE DISSERTATION

A Mechanism of Antimicrobial Resistance and a Mitigation Strategy

by

Christopher Bulow

Doctor of Philosophy in Biology and Biomedical Sciences

Molecular Genetics and Genomics

Washington University in St. Louis, 2018

Professor Gautam Dantas, Chair

The ability to treat infections, perform surgery, and administer immunosuppressants and chemotherapy depends on effective antibiotics. The emergence and spread of antimicrobial resistance is far outpacing the development of new therapies1-3 threatening to thrust medicine into a post-antibiotic era4. Many mechanisms of antimicrobial action and of antimicrobial resistance remain poorly understood as drug development struggles to keep pace. As resistance develops, the …


Functional And Skeletal Muscle Impairments In Progressive Diabetic Ckd, Daniel Bittel Aug 2018

Functional And Skeletal Muscle Impairments In Progressive Diabetic Ckd, Daniel Bittel

Arts & Sciences Electronic Theses and Dissertations

1-in-3 persons with type 2 diabetes (T2DM) develop chronic kidney disease (CKD), which is characterized by progressive renal dysfunction leading to end-stage renal disease. In response to elevated blood glucose and systemic inflammation of diabetes, a process of active thickening of the renal glomerular basement membrane ensues with concomitant damage to the structural supports (podocytes) of the kidneyճ filtration barrier. This results in impaired renal filtration. The metabolic sequelea of T2DM and CKD also, synergistically, alter skeletal muscleճ degradative pathways, satellite cell function (muscle reparative cells), and mitochondrial health (muscle energetic machinery) -- resulting in muscle breakdown, poor muscle quality, …


Viral Mhc Class I Evasion Affects Anti-Viral T Cell Development And Responses, Elvin James Lauron Aug 2018

Viral Mhc Class I Evasion Affects Anti-Viral T Cell Development And Responses, Elvin James Lauron

Arts & Sciences Electronic Theses and Dissertations

Cytotoxic CD8+ T cells (CTLs) play a critical role in protective immunity against viruses, a fact underscored by the evolution of viral CTL evasion mechanisms. For instance, many viruses commonly target the major histocompatibility complex class I (MHCI) antigen presentation pathway to prevent CTLs from recognizing infected cells. A striking example of this is cowpox virus (CPXV), which interferes with MHCI antigen presentation through two distinct mechanisms. One mechanism of CPXV-mediated MHCI inhibition is to retain MHCI molecules in the endoplasmic reticulum (ER). The second mechanism is to prevent antigen peptide loading onto MHCI molecules. When combined these mechanisms result …


Methods To Record Transcription Factor Binding And Enhancer Activity Throughout Cellular Differentiation, Zongtai Qi Aug 2018

Methods To Record Transcription Factor Binding And Enhancer Activity Throughout Cellular Differentiation, Zongtai Qi

Arts & Sciences Electronic Theses and Dissertations

The ability to create distinct cell types is fundamental for the development of multicellular organisms. Since all cells in an organism contain the same genes, cellular diversity is achieved through the transcriptional network where transcription factors (TFs) interacts with cis-regulatory elements, leading to the selective transcription of different sets of genes. To better understand the functions of TFs and regulatory elements underlying cell fate decisions, we developed methods that are able to record their activities throughout cellular differentiation. In Chapter 2, we developed a degradation domain based induction system for ҃alling CardsӠmethod which maps the binding sites of TFs using …


The Costs Of A Big Brain: How Region Scaling And Energetic Costs Influence Brain Size Evolution In Weakly Electric African Fishes (Mormyridae), Kimberley Varunee Sukhum Aug 2018

The Costs Of A Big Brain: How Region Scaling And Energetic Costs Influence Brain Size Evolution In Weakly Electric African Fishes (Mormyridae), Kimberley Varunee Sukhum

Arts & Sciences Electronic Theses and Dissertations

Brains control an organismճ ability to sense, remember, and respond to the frequently changing world. Brains are composed of multiple regions and systems, which are associated with different processes. These regions are homologous across all vertebrates yet vary greatly in size and shape across clades. While regions can function independently, they also interact extensively. These characteristics make it difficult to predict whether regions can change in size independently from other regions in response to selection (mosaic evolution hypothesis), or whether the brain evolves as a single concerted organ (concerted evolution hypothesis). Further, many traits such as cognition, behavioral flexibility, and …


Evaluation Of Neurobiological Risk Factors For Alcohol Consumption; Convergent Evidence For Predispositional Effects Of Brain Volume, David Baranger Aug 2018

Evaluation Of Neurobiological Risk Factors For Alcohol Consumption; Convergent Evidence For Predispositional Effects Of Brain Volume, David Baranger

Arts & Sciences Electronic Theses and Dissertations

Alcohol is one of the most widely used psychoactive substances and accounts for 5% of global disease burden. The goal of the present work is to help advance efforts to both identify prognostic markers of risk, and to understand the mechanisms by which alcohol consumption impacts health. Early life stress is one of the strongest predictors of mental illness, including alcohol dependence, and has been hypothesized to impact risk via modulation of striatal reward functions and reward learning. Studies examined the effect of stress on reward learning and processing, and tested for moderation by genetic and environmental risk. Results were …


Preventing Extinction Of At-Risk Plant Species In A Complex World, Holly Lee Bernardo Aug 2018

Preventing Extinction Of At-Risk Plant Species In A Complex World, Holly Lee Bernardo

Arts & Sciences Electronic Theses and Dissertations

Earthճ current biodiversity crisis is now considered a true mass extinction event, with species level extinction rates well above background rates and population level extinction rates orders of magnitude more common that species extinctions. There are many threats driving this loss of biodiversity. How each threat impacts the viability of a species is highly context dependent, but all are anthropogenic in origin and so as the human population continues to increase, so too will the pressure of these threats on our natural systems. Ultimately, how much a threat decreases the viability of a species depends on how that threat influences …