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2015

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Characterization Of The Function Of The Dead-Box Rna Helicase Dbp2, Wai Kit Ma Jan 2015

Characterization Of The Function Of The Dead-Box Rna Helicase Dbp2, Wai Kit Ma

Open Access Dissertations

In eukaryotes, there are highly coupled mechanisms that require RNA-binding proteins to facilitate gene expression. Proper RNA structure and ribonucleoprotein (RNP) complex formation are critical for gene expression. DEAD-box proteins are the largest class of RNA helicases that play fundamental roles in RNA and RNP structure remodeling. However, the precise biological role of the vast majority of the ~ 40 members in this family has not been completely described. Therefore, my research focused on characterizing the role of the DEAD-box RNA helicase Dbp2 during gene expression in S. cerevisiae.

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Second Language Writing Instructor Written Feedback Practices In An Esl Freshman Composition Class: A Complexity Theory Perspective, Masakazu Mishima Jan 2015

Second Language Writing Instructor Written Feedback Practices In An Esl Freshman Composition Class: A Complexity Theory Perspective, Masakazu Mishima

Open Access Dissertations

This case study investigated second language writing instructors’ written feedback practices from a complexity theory perspective. The purpose of the research was to explore and examine contextual factors and their impact on instructor written feedback practices. Data were collected from two ESL writing instructors and two ESL writers through surveys, interviews, and classroom observations. Based on the results, a complexity theory-based model of second language writing instructor written feedback practices was developed to represent the complexity of written feedback practice situated in the specific instructional context. The findings suggest that the instructors were under constant influence of five different contextual …

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Manganese Toxicity: Accumulation In Bone, Effect On Brain Neurochemistry, And Impact On Adult Neurogenesis, Stefanie O'Neal Jan 2015

Manganese Toxicity: Accumulation In Bone, Effect On Brain Neurochemistry, And Impact On Adult Neurogenesis, Stefanie O'Neal

Open Access Dissertations

O’Neal, Stefanie L. Ph.D., Purdue University, December 2015. Manganese Toxicity: Accumulation in Bone, Effect on Neurochemistry, Impact on Adult Neurogenesis. Major Professor: Wei Zheng.

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Proteogenomic Insights Into The Nature Of Chemoresistance In Chronic Myelogenous Leukemia, Brett Noel Jan 2015

Proteogenomic Insights Into The Nature Of Chemoresistance In Chronic Myelogenous Leukemia, Brett Noel

Open Access Dissertations

Chronic Myelogenous Leukemia (CML) is a hematopoietic cancer caused by the formation of the Philadelphia chromosome, a reciprocal translocation of the ABL1 oncogene on chromosome 9, and the breakpoint cluster region gene (BCR) chromosome 22, resulting in the BCR-ABL oncoprotein. BCR-ABL is a constitutively active tyrosine kinase that regulates cell growth and differentiation, leading to uncontrolled cell proliferation by deregulating downstream signaling pathways.

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Investigation Of Noise Sources And Propagation In External Gear Pumps, Timothy John Opperwall Jan 2015

Investigation Of Noise Sources And Propagation In External Gear Pumps, Timothy John Opperwall

Open Access Dissertations

Oil hydraulics is widely accepted as the best technology for transmitting power in many engineering applications due to its advantages in power density, control, layout flexibility, and efficiency. Due to these advantages, hydraulic systems are present in many different applications including construction, agriculture, aerospace, automotive, forestry, medical, and manufacturing, just to identify a few. Many of these applications involve the systems in close proximity to human operators and passengers where noise is one of the main constraints to the acceptance and spread of this technology.

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Associations Between The Built Environment And Physical Activity From Analyses Of Spatial Clusters, Trail Use, And Locations Where Physical Activity Occurs, Kosuke Tamura Jan 2015

Associations Between The Built Environment And Physical Activity From Analyses Of Spatial Clusters, Trail Use, And Locations Where Physical Activity Occurs, Kosuke Tamura

Open Access Dissertations

Over the past two decades, an increasing number of scientific studies have examined associations between the built environment and physical activity and obesity. These studies have documented positive associations between environmental variables, such as population density, street connectivity, and composite measures of neighborhood walkability and physical activity. Studies have also shown inverse relationships between the presence of neighborhood grocery stores and recreational facilities and obesity. Despite this evidence, there continues to be limitations in built environment studies conducted to date. The three dissertation studies described here were designed to address several different aspects of built environment research that warrant greater …

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Mental Health And Human Minds: Some Theoretical Criteria For Clinical Psychiatry, Natalia Washington Jan 2015

Mental Health And Human Minds: Some Theoretical Criteria For Clinical Psychiatry, Natalia Washington

Open Access Dissertations

When it comes to the topic of mental illness, there are three broad areas of concern that are of interest to all of us as human beings—and to the theorists, researchers, and clinicians who wish to offer help—besides knowing what our symptoms are. First, we might be interested in finding out some normative facts about ourselves as individuals, such as whether or not we are mentally healthy, perhaps to what extent, and how this should affect our motivations. A second area of concern involves descriptive facts our minds. In what ways do we deviate from typical human psychological nature, and …

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The World Become Image: Nonrepresentational Discussions Of Film And The Natural World, Gary Matthew Varner Jan 2015

The World Become Image: Nonrepresentational Discussions Of Film And The Natural World, Gary Matthew Varner

Open Access Dissertations

This dissertation investigates the relationships between film and the natural world. Building upon extant work in the burgeoning field of Ecocinema, this project attempts to move beyond the scholarly work on Ecocinema that satisfies itself with questions of representation. The issues and arguments taken up here tend to be more programmatic. This work is interested in ecological exchanges, encounters, and relationships, not representations. The first chapter introduces the project, its origins, and the philosophical motivations for working outside the mode of representation. The second chapter excavates a concern for animals and the environment within the margins and subtext of classical …

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A General Purpose Programmable Microfluidic Platform For Screening And Optimization Of Biological Assays, Raviraj Thakur Jan 2015

A General Purpose Programmable Microfluidic Platform For Screening And Optimization Of Biological Assays, Raviraj Thakur

Open Access Dissertations

Screening is a fundamental process in today’s medicine and clinical diagnostics, comprising of several processes ranging from finding new target molecules having the desired therapeutic potential to identifying biomarkers for accurate diagnosis of a spectrum of diseases. Current high throughput screening (HTS) platforms leverage sophisticated robotics to perform a large number of experiments very quickly, an otherwise unmanageable task with manual labor. However, these systems are capital intensive which limit their use to large pharmaceutical companies or larger research labs. Additionally, reagent consumption is of the order of 10-100 µL per assay, which leads to substantial consumables cost. Recently proposed …

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Framework For Incorporating Network Connectivity In Transportation Systems Evaluation, Wubeshet Woldemariam Jan 2015

Framework For Incorporating Network Connectivity In Transportation Systems Evaluation, Wubeshet Woldemariam

Open Access Dissertations

In transportation investment evaluation, agencies often do not consider the impact of proposed projects in terms of the increased connectivity of the parent network. Thus, agencies may be inadvertently omitting a key and critical goal of transportation investment evaluation and decision making, particularly in regions and countries with sparse networks. This dissertation develops a framework for measuring network connectivity performance for use as an input for the evaluation process and is applicable to existing or proposed networks in any mode of transportation. The steps for the framework include selection of network performance measures (PMs), scaling the PMs, determining the level …

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Design, Synthesis, And Biological Evaluation Of Novel Indenoisoquinolines As Potential Anticancer Agents, Daniel Edward Beck Jan 2015

Design, Synthesis, And Biological Evaluation Of Novel Indenoisoquinolines As Potential Anticancer Agents, Daniel Edward Beck

Open Access Dissertations

The research in this thesis is focused on the design, synthesis, and biological evaluation of indenoisoquinolines that inhibit the human topoisomerase IB enzyme (Top1). At present, there are only two FDA-approved cancer chemotherapeutic drugs that target this enzyme. These agents bind to a covalent Top1-DNA cleavage complex intermediate that is formed when Top1 relaxes supercoiled DNA. The effect of this stabilization is that a DNA replication fork can “collide” with the cleavage complex, which produces cytotoxic DNA damage products. Although the present arsenal of Top1 inhibitors is effective in the treatment of solid tumors, their common camptothecin-based structure is plagued …

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Miniature Mass Spectrometer System With A Sampling Probe, Chien-Hsun Chen Jan 2015

Miniature Mass Spectrometer System With A Sampling Probe, Chien-Hsun Chen

Open Access Dissertations

This thesis focuses on the development of miniature mass spectrometry systems and the sampling probes. Mass spectrometers are usually installed and used in the analytical laboratory. It requires complex sample preparation before the analysis. Use of miniature mass spectrometer enables the chemical analysis outside the lab and a sampling probe provides convenience for real-time analysis. Two miniature mass spectrometer systems have been developed in this work.

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High Pressure Micro-Scale Studies Of Fast-Hydropyrolysis And Catalytic Hydrogenation Of Biomass And Related Model Compounds, Harshavardhan Choudhari Jan 2015

High Pressure Micro-Scale Studies Of Fast-Hydropyrolysis And Catalytic Hydrogenation Of Biomass And Related Model Compounds, Harshavardhan Choudhari

Open Access Dissertations

Biomass is a major source of renewable carbon which can be converted to hydrocarbon fuel with the aim of reducing the dependence on fossil based sources. Fast pyrolysis of biomass followed by catalytic hydrodeoxygenation of bio-oil is considered a promising biomass conversion route to produce drop in hydrocarbon fuels. The H2Bioil process was proposed as an integrated high pressure fast hydropyrolysis and catalytic vapor phase hydrodeoxygenation (HDO) pathway for utilizing biomass to produce high energy density fuel. During fast hydropyrolysis biomass is rapidly heated to generate a complex mixture of compounds with high oxygen content (35-40 wt %). In the …

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Influence Of Social Cognitive Variables On The Career Exploratory Behaviors Of African American Undergraduate Stem-Intensive Agricultural Sciences Majors At Historically Black Land-Grant Institutions, Qi Ding Jan 2015

Influence Of Social Cognitive Variables On The Career Exploratory Behaviors Of African American Undergraduate Stem-Intensive Agricultural Sciences Majors At Historically Black Land-Grant Institutions, Qi Ding

Open Access Dissertations

Without question, racial and ethnic minority groups are playing more significant roles in American society. However, there still remains a lack of diversity within the STEM workforce, especially within agricultural sciences disciplines. More problematic is the fact that low numbers of African Americans are employed in the agricultural sciences workforce. This study extends the use of Social Cognitive Career Theory by exploring how person, contextual and cognitive factors interplay to influence the career goals and career exploratory behaviors of African American college students pursuing STEM-intensive agricultural sciences majors. Instruments were selected to measure various components of the SCCT framework, focusing …

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Physical Chemistry Of Colloidal-Nanoparticle Interactions, Necla Mine Eren Jan 2015

Physical Chemistry Of Colloidal-Nanoparticle Interactions, Necla Mine Eren

Open Access Dissertations

Following the advances in the design and characterization of engineered nanoparticles, biomaterials came into contact with the nano-world. Among many implementations of bio-nanotechnology, there is an increasing scientific and industrial interest in designing complex/hybrid structures (micro/macro) by merging the advantageous of inorganic colloidal particles (fixed shape, hard matter) with organic biopolymers (flexible shape, soft matter).In the current dissertation, nanostructured silica suspensions with tunable rheological characteristics were designed via steric and electrostatic interactions. Perturbation of short range interactions, protein bridging and silica re-dispersion were reported to play key roles in the macro-structure formation as determined by light scattering, steady state shear …

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Functional Study Of Mammary Epithelial Cell Architecture, Yunfeng Bai Jan 2015

Functional Study Of Mammary Epithelial Cell Architecture, Yunfeng Bai

Open Access Dissertations

Cell organization confers cellular identity and guides cellular functions. Here, the

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A Comparison Of Functionally Divergent Forms Of The Purine Biosynthesis Enzyme Pure., Kelly L. Sullivan Jan 2015

A Comparison Of Functionally Divergent Forms Of The Purine Biosynthesis Enzyme Pure., Kelly L. Sullivan

Open Access Dissertations

Purines are the basic building block for essential biomolecules such as DNA, RNA, NADH, CoA, and several essential vitamin cofactors. Most organisms have the ability to synthesize purines through the de novo purine biosynthesis pathway.

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Genetic Regulation Of Maize And Sorghum Under Abiotic Stress, Alexandar Lewis Renaud Jan 2015

Genetic Regulation Of Maize And Sorghum Under Abiotic Stress, Alexandar Lewis Renaud

Open Access Dissertations

Climate extremes of temperature, drought and flooding continue to challenge global agricultural production and food security. If modeling studies are accurate, climate variability and drought will be a more prevalent occurrence in the future, not only inhibiting grain yield but also stressing water resources. Thus, it is critical to breed for improved climate resilience in agronomic crops and understand the genetic mechanisms conferring adaptation to water-limited environments.

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Immunotherapy Of Folate Receptor Expressing Cancers, Nimalka Achini Bandara Jan 2015

Immunotherapy Of Folate Receptor Expressing Cancers, Nimalka Achini Bandara

Open Access Dissertations

The folate receptor (FR) is a GPI anchored cell surface glycoprotein that functions to facilitate folic acid uptake and mediate signal transduction. With the introduction of multiple folate-targeted drugs into the clinic, the question has arisen regarding how frequently a patient can be dosed with a FR-targeted drug or antibody, and whether dosing frequency exerts any impact on the availability of FR for subsequent rounds of FR-mediated drug uptake. Although the rate of FR recycling has been examined in murine tumor models, little or no information exists on the impact of FR occupancy on its rate of endocytosis. The studies …

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Notch Signaling Regulates Adipogenesis And Energy Metabolism, Pengpeng Bi Jan 2015

Notch Signaling Regulates Adipogenesis And Energy Metabolism, Pengpeng Bi

Open Access Dissertations

Evolutionarily unprepared for high caloric diets and sedentary lifestyles, humans are now unprecedentedly susceptible to obesity and its associated metabolic disorders. Obesity is resulted from malfunction of the overloaded white adipocytes, which are the primary default storage sites of energy surplus. Another two types of adipocytes can also be found in human: beige and brown adipocytes. In opposite to white adipocytes, beige and brown adipocytes ameliorate obesity by burning lipids for thermogenesis. Thus, an increase in beige/brown adipocyte content in adipose tissue, termed browning would raise energy expenditure and reduce adiposity.

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Enabling New Functionally Embedded Mechanical Systems Via Cutting, Folding, And 3d Printing, Wei Gao Jan 2015

Enabling New Functionally Embedded Mechanical Systems Via Cutting, Folding, And 3d Printing, Wei Gao

Open Access Dissertations

Traditional design tools and fabrication methods implicitly prevent mechanical engineers from encapsulating full functionalities such as mobility, transformation, sensing and actuation in the early design concept prototyping stage. Therefore, designers are forced to design, fabricate and assemble individual parts similar to conventional manufacturing, and iteratively create additional functionalities. This results in relatively high design iteration times and complex assembly strategies.

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A Bio-Inspired Self-Healing Polymer System For Sustainable Plastics, Michael Laird Johnston Jan 2015

A Bio-Inspired Self-Healing Polymer System For Sustainable Plastics, Michael Laird Johnston

Open Access Dissertations

Studying how marine organisms make tough biologic materials that autonomously heal allows us to integrate this biological self-healing motif into synthetic biomimetic polymers. These types of polymers will be used to develop components with greater fatigue life and toughness, promoting greater resource sustainability by reducing plastic consumption. The amino acid 3,4-dihydroxyphenylalanine (DOPA) grants marine mussels the ability to strongly affix themselves to the rocks under water by forming strong reversible bonds with their environment. Poly[(3,4-dihydroxystyrene)-co-styrene)] (P[3,4-DHS-S]) is a synthetic polymer mimic of DOPA with chemical structure similar to polystyrene (PS) with a potential self-healing mechanism. This intrinsic self-healing mechanism works …

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Smart Cities: Inverse Design Of 3d Urban Procedural Models With Traffic And Weather Simulation, Ignacio Garcia Dorado Jan 2015

Smart Cities: Inverse Design Of 3d Urban Procedural Models With Traffic And Weather Simulation, Ignacio Garcia Dorado

Open Access Dissertations

Urbanization, the demographic transition from rural to urban, has changed how we envision and share the world. From just one-fourth of the population living in cities one hundred years ago, now more than half of the population does, and this ratio is expected to grow in the near future. Creating more sustainable, accessible, safe, and enjoyable cities has become an imperative.

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Finite Element Analysis Of The Equine Distal Limb Transfixation Cast, Timothy B. Lescun Jan 2015

Finite Element Analysis Of The Equine Distal Limb Transfixation Cast, Timothy B. Lescun

Open Access Dissertations

Lescun, Timothy B. Ph.D., Purdue University, December 2015. Finite Element Analysis of the Equine Distal Limb Transfixation Cast. Major Professors: Gert Breur and Eric Nauman.

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Analysis Of Models For Curvature Driven Motion Of Interfaces, Drew Swartz Jan 2015

Analysis Of Models For Curvature Driven Motion Of Interfaces, Drew Swartz

Open Access Dissertations

Interfacial energies frequently appear in models arising in materials science and engineering.

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Influence Of Architecture Design On The Performance And Fuel Efficiency Of Hydraulic Hybrid Transmissions, Michael Wayne Sprengel Jan 2015

Influence Of Architecture Design On The Performance And Fuel Efficiency Of Hydraulic Hybrid Transmissions, Michael Wayne Sprengel

Open Access Dissertations

Hydraulic hybrids are a proven and effective alternative to electric hybrids for increasing the fuel efficiency of on-road vehicles. To further the state-of-the-art this work investigates how architecture design influences the performance, fuel efficiency, and controllability of hydraulic hybrid transmissions. To that end a novel neural network based power management controller was proposed and investigated for conventional hydraulic hybrids. This control scheme trained a neural network to generalize the globally optimal, though non-implementable, state trajectories generated by dynamic programming. Once trained the neural network was used for online prediction of a transmission’s optimal state trajectory during untrained cycles forming the …

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On Computational Synthesis And Dynamic Analysis Of Nonlinear Resonant Systems With Internal Resonances, Astitva Tripathi Jan 2015

On Computational Synthesis And Dynamic Analysis Of Nonlinear Resonant Systems With Internal Resonances, Astitva Tripathi

Open Access Dissertations

This work is concerned with synthesis methods for nonlinear structures and the

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Indices And Ecoinformatics Tools For The Study Of Soundscape Dynamics, Luis Javier Villanueva-Rivera Jan 2015

Indices And Ecoinformatics Tools For The Study Of Soundscape Dynamics, Luis Javier Villanueva-Rivera

Open Access Dissertations

The study of the new field of soundscape ecology presents several research avenues to explore. In the chapters in this dissertation, I have followed several of the technical and methodological areas of the study of soundscapes. In Chapter 1, I presented the current status of the study of soundscapes as well as an overview of the contributions made in this dissertation to the field. These contributions were framed in the definition of ecological informatics (Michener and Jones 2012). In Chapter 2, I developed a web-based system to manage audio archives. This system organizes thousands of audio files while collecting the …

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Design And Control Of A Hummingbird-Size Flapping Wing Micro Aerial Vehicle, Jian Zhang Jan 2015

Design And Control Of A Hummingbird-Size Flapping Wing Micro Aerial Vehicle, Jian Zhang

Open Access Dissertations

Flying animals with flapping wings may best exemplify the astonishing ability of natural selection on design optimization. They evince extraordinary prowess to control their flight, while demonstrating rich repertoire of agile maneuvers. They remain surprisingly stable during hover and can make sharp turns in a split second. Characterized by high-frequency flapping wing motion, unsteady aerodynamics, and the ability to hover and perform fast maneuvers, insect-like flapping flight presents an extraordinary aerial locomotion strategy perfected at small size scales. Flapping Wing Micro Aerial Vehicles (FWMAVs) hold great promise in bridging the performance gap between engineered flying vehicles and their natural counterparts. …

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Understanding The Determinants For Substrate Recognition, Regulation Of Enzymatic Activity And The Development Of Broad-Spectrum Inhibitors Of Coronavirus 3-Chymotrypsin-Like Proteases, Sakshi Tomar Jan 2015

Understanding The Determinants For Substrate Recognition, Regulation Of Enzymatic Activity And The Development Of Broad-Spectrum Inhibitors Of Coronavirus 3-Chymotrypsin-Like Proteases, Sakshi Tomar

Open Access Dissertations

Coronaviruses include lethal human pathogens like severe acute respiratory syndrome coronavirus (SARS-CoV) and the recently emerged Middle-east respiratory coronavirus (MERS-CoV). Coronavirus also impact global economy by infecting farm animals like pigs (porcine epidemic diarrhea virus, PEDV), cows (bovine coronavirus, BCoV) and poultry (avian infectious bronchitis virus, IBV). Moreover, the global distribution of bats that naturally harbor one or more coronavirus strains heightens the likelihood of emergence of a novel highly pathogenic coronavirus in the near future. To combat infections of existing and emerging coronaviruses, it is important to identify coronavirus drug targets that can be utilized for the development of …

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