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The Evolution Of Transposable Elements As Cis-Regulatory Elements In Mammals, Alan Y. Du

Arts & Sciences Electronic Theses and Dissertations

Transposable elements (TEs) are mobile genetic elements that make up a large proportion of mammalian genomes. Although TEs are highly prevalent genomic sequences, they have been understudied as they were once labeled as “junk DNA.” Despite their initial status as simple genomic parasites, recent studies have implicated TEs as cis-regulatory elements, supplying promoters, enhancers, and boundary elements. Functional testing of regulatory activity, however, remains a significant bottleneck. Nonetheless, due to their repetitive nature, TEs provide a unique model to examine the evolution of cis-regulatory elements, which has traditionally been difficult to study due to lack of homology at the sequence …

The Evolutionary History Of Camelina Crantz (Brassicaceae) And Domestication Of The Biofuel Crop, C. Sativa (L.) Crantz, Jordan Brock

Arts & Sciences Electronic Theses and Dissertations

The mustard family, Brassicaceae, is a large and economically important group of plants comprising ~350 genera and ~4060 species. Within the family, one genus, Camelina, has been neglected and nearly forgotten until recent decades. This genus comprises between 7 – 9 species, and includes Camelina sativa, an ancient oilseed crop cultivated for thousands of years in Europe. An allohexaploid, C. sativa contains high levels of omega-3 fatty acids and a seed oil composition amenable for production of aviation jet fuel. With a short generation time and ability to be cultivated on marginal soils with few inputs, C. sativa is set …

Pillars Of The Nutrition Transition: The Global Impacts Of Ultra-Processed Foods And Beverages On Overweight And Obesity And National Nutrient Supplies, Jacob Eaton

Arts & Sciences Electronic Theses and Dissertations

Malnutrition in some form impacts nearly one-third of the global population. Across the world, countries are undergoing the Үutrition transitionӠfrom traditional and largely unprocessed diets to Western-style, energy-dense diets. At the same time, rates of overweight and obesity and diet-related chronic diseases continue to climb. Ultra-processed foods (UPF), sugar-sweetened beverages (SSB), and vegetable oils are three of the foods driving the nutrition transition. This dissertation calculates changes in the global food supply between 1961 and 2013 and quantifies the influence of UPF and SSB (as measured through sales) on national nutrient supplies between 2005 and 2013 and trends in adult …

Robust Algorithms For Detecting Hidden Structure In Biological Data, Roman Sloutsky

Arts & Sciences Electronic Theses and Dissertations

Biological data, such as molecular abundance measurements and protein

sequences, harbor complex hidden structure that reflects its underlying

biological mechanisms. For example, high-throughput abundance measurements

provide a snapshot the global state of a living cell, while homologous

protein sequences encode the residue-level logic of the proteins' function

and provide a snapshot of the evolutionary trajectory of the protein family.

In this work I describe algorithmic approaches and analysis software I

developed for uncovering hidden structure in both kinds of data.

Clustering is an unsurpervised machine learning technique commonly used

to map the structure of data collected in high-throughput experiments,

such …

The Solid & The Shifting: Darwinian Time, Evolutionary Form And The Greek Ideal 
In The Early Works Of Virginia Woolf, Joseph Monroe Kreutziger

Arts & Sciences Electronic Theses and Dissertations

ABSTRACT OF THE DISSERTATION

“The Solid & the Shifting”: Evolutionary Form, Darwinian Time, and the Greek Ideal in the Early Works of Virginia Woolf

By

Joseph Kreutziger

Doctor of Philosophy in English and American Literature

Washington University in St. Louis, 2017

Professors Melanie Micir, Robert Milder, Steven Meyer, Vincent Sherry, Zoe Stamatopoulou

_____________________________________________________________________

“Now is life very solid or very shifting?” Virginia Woolf asks in her diary of 1931, a question she claims haunts her in its contradictions. This dynamism between the solid and the shifting aspects of life and temporality is fundamental to an analysis of Woolf’s writing process. …

Peripheral And Central Mechanisms Of Temporal Pattern Recognition, Christa Ann Baker

Arts & Sciences Electronic Theses and Dissertations

Encoding information into the timing patterns of action potentials, or spikes, is a strategy used broadly in neural circuits. This type of coding scheme requires downstream neurons to be sensitive to the temporal patterns of presynaptic inputs. Indeed, neurons with temporal filtering properties have been found in a wide range of sensory pathways. However, how such response properties arise was previously not well understood. The goal of my dissertation research has been to elucidate how temporal filtering by single neurons contributes to the behavioral ability to recognize timing patterns in communication signals.

I have addressed this question using mormyrid weakly …

Evolutionary Developmental Leaf Morphology Of The Plant Family Araceae, Claudia Liliana Henriquez

Arts & Sciences Electronic Theses and Dissertations

Studying the evolutionary developmental morphology of leaves using next-generation phylogenetics, a candidate gene approach and comparative developmental studies in the plant family Araceae is the overarching theme of the dissertation.

The plant family Araceae is an ancient lineage from the Early Cretaceous and belongs to the monocotyledons. Members of Araceae display striking variation in leaf development; such variation contradicts traditional models of monocot leaf development. Additionally, dissected leaves, which are rare in monocots, seem to have evolved independently multiple times in Araceae by various developmental mechanisms.

Despite extensive efforts to elucidate the evolutionary history of Araceae, phylogenetic ambiguity in the …

The U1a/U2b"/Snf Family Of Rna Binding Proteins: Evolution Of Rna Binding Specificity And Contributions Of Heterotropic Linkage To Snrnp Protein Partitioning, Sandra Gisela Williams

Arts & Sciences Electronic Theses and Dissertations

The U1A/U2B"/SNF is a family of RNA binding proteins that is a highly conserved throughout eukaryotes. These proteins are found in the U1 and/or U2 splicing snRNPs (small nuclear ribonucleoprotein particles). In humans, U1A and U2B" specifically bind to the U1 and U2 snRNAs, respectively. The Drosophila genome codes for SNF, an essential protein that localizes to both the U1 and U2 snRNP. While a specific splicing functions for these proteins have not been determined, their conserved snRNP localization suggests an important splicing-related function.

The difference in protein number and partitioning between Drosophila and humans suggested that these proteins may …

Characterizing The Fitness Landscapes Of Gut Symbionts In Defined Community And Diet Contexts, Meng Wu

Arts & Sciences Electronic Theses and Dissertations

A species' niche is the description of all the environmental conditions required to permit a population of that species to persist, including the effects of the population on those conditions. This definition includes the species' resource requirements, as well as stress tolerances and interactions with other species acting as competitors, predators, parasites, and mutualists. The human gut microbiota serves as a microbial `metabolic organ' tasked in part with the biotransformation of many components of our diet. Relatively little is known about the factors that allow members of the human gut microbiota to persist in a habitat that experiences marked changes …

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 …