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Room Temperature Ferroelectricity In Fluoroperovskite Thin Films, Ming Yang, Amit Kc, A C Garcia-Castro, Pavel Borisov, E Bousquet, David Lederman, Aldo H. Romero, Cheng Cen Jan 2017

Room Temperature Ferroelectricity In Fluoroperovskite Thin Films, Ming Yang, Amit Kc, A C Garcia-Castro, Pavel Borisov, E Bousquet, David Lederman, Aldo H. Romero, Cheng Cen

Faculty & Staff Scholarship

The NaMnF3 fluoride-perovskite has been found, theoretically, to be ferroelectric under epitaxial strain becoming a promising alternative to conventional oxides for multiferroic applications. Nevertheless, this fluoroperovskite has not been experimentally verified to be ferroelectric so far. Here we report signatures of room temperature ferroelectricity observed in perovskite NaMnF3 thin films grown on SrTiO3. Using piezoresponse force microscopy, we studied the evolution of ferroelectric polarization in response to external and built-in electric fields. Density functional theory calculations were also performed to help understand the strong competition between ferroelectric and paraelectric phases as well as the profound influences of strain. These results, …

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Sulfide Generation By Dominant Halanaerobium Microorganisms In Hydraulically Fractured Shales, Anne E. Booker, Mikayla A. Borton, Rebecca A. Daly, Susan A. Welch, Carrie D. Nicora, David W. Hoyt, Travis Wilson, Samuel O. Purvine, Richard A. Wolfe, Shikha Sharma, Paula J. Mouser, David R. Cole, Mary S. Lipton, Kelly C. Wrighton, Michael J. Wilkins Jan 2017

Sulfide Generation By Dominant Halanaerobium Microorganisms In Hydraulically Fractured Shales, Anne E. Booker, Mikayla A. Borton, Rebecca A. Daly, Susan A. Welch, Carrie D. Nicora, David W. Hoyt, Travis Wilson, Samuel O. Purvine, Richard A. Wolfe, Shikha Sharma, Paula J. Mouser, David R. Cole, Mary S. Lipton, Kelly C. Wrighton, Michael J. Wilkins

Faculty & Staff Scholarship

Hydraulic fracturing of black shale formations has greatly increased United States oil and natural gas recovery. However, the accumulation of biomass in subsurface reservoirs and pipelines is detrimental because of possible well souring, microbially induced corrosion, and pore clogging. Temporal sampling of produced fluids from a well in the Utica Shale revealed the dominance of Halanaerobium strains within the in situ microbial community and the potential for these microorganisms to catalyze thiosulfate-dependent sulfidogenesis. From these field data, we investigated biogenic sulfide production catalyzed by a Halanaerobium strain isolated from the produced fluids using proteogenomics and laboratory growth experiments. Analysis of …

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Characteristics Of Successful Puma Kill Sites Of Elk In The Black Hills, South Dakota, Chadwick P. Lehman, Christopher T. Rota, Mark A. Rumble, Joshua J. Millspaugh Jan 2017

Characteristics Of Successful Puma Kill Sites Of Elk In The Black Hills, South Dakota, Chadwick P. Lehman, Christopher T. Rota, Mark A. Rumble, Joshua J. Millspaugh

Faculty & Staff Scholarship

Elk Cervus canadensis nelsoni in the Black Hills, South Dakota, have been declining since 2006 and there is concern by resource managers and hunters that puma Puma concolor predation may be contributing to declining herds. We evaluated characteristics at sites where puma successfully killed elk in the Black Hills of South Dakota. We evaluated characteristics at coarse (79-ha plots) and fine (0.2-ha plot) scales across the landscape. Our primary objective was to obtain a better understanding of vegetation and terrain characteristics that may have facilitated greater susceptibility of elk to predation by puma. We evaluated effects of road density, terrain …

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Modified Lipid Extraction Methods For Deep Subsurface Shale, Rawlings N. Akondi, Ryan V. Trexler, Susan M. Pfiffner, Paula J. Mouser, Shikha Sharma Jan 2017

Modified Lipid Extraction Methods For Deep Subsurface Shale, Rawlings N. Akondi, Ryan V. Trexler, Susan M. Pfiffner, Paula J. Mouser, Shikha Sharma

Faculty & Staff Scholarship

Growing interest in the utilization of black shales for hydrocarbon development and environmental applications has spurred investigations of microbial functional diversity in the deep subsurface shale ecosystem. Lipid biomarker analyses including phospholipid fatty acids (PLFAs) and diglyceride fatty acids (DGFAs) represent sensitive tools for estimating biomass and characterizing the diversity of microbial communities. However, complex shale matrix properties create immense challenges for microbial lipid extraction procedures. Here, we test three different lipid extraction methods: modified Bligh and Dyer (mBD), Folch (FOL), and microwave assisted extraction (MAE), to examine their ability in the recovery and reproducibility of lipid biomarkers in deeply …

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Periodontal Status And Quality Of Life: Impact Of Fear Of Pain And Dental Fear, Casey D. Wright, Daniel W. Mcneil, Cierra B. Edwards, Richard J. Crout, Katherine Neiswanger, John R. Shaffer, Mary L. Marzita Jan 2017

Periodontal Status And Quality Of Life: Impact Of Fear Of Pain And Dental Fear, Casey D. Wright, Daniel W. Mcneil, Cierra B. Edwards, Richard J. Crout, Katherine Neiswanger, John R. Shaffer, Mary L. Marzita

Faculty & Staff Scholarship

Background. Oral health-related quality of life (OHRQoL) is impacted by periodontal disease and orofacial pain. There is a limited research examining the impact of avoidance of care or physiological arousal related to the fear of pain response on periodontal-related OHRQoL. Methods. Data are from the Center for Oral Health Research in Appalachia family-based study focusing on 1,339 adults. Measures included a modified Periodontal Screening and Recording Index across sextants of dentition, dental fear survey, Fear of Pain Questionnaire-9, and Oral Health Impact Profile-14. Structural equation modeling was used to estimate the effects of periodontal disease screening indicators on OHRQoL including …

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The Infrared And Radio Flux Densities Of Galactic H Ii Regions, Z. Makai, L. D. Anderson, J. L. Mascoop, B. Johnstone Jan 2017

The Infrared And Radio Flux Densities Of Galactic H Ii Regions, Z. Makai, L. D. Anderson, J. L. Mascoop, B. Johnstone

Faculty & Staff Scholarship

No abstract provided.

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Tunneling Conductance In Semiconductor-Superconductor Hybrid Structures, John Stenger, Tudor D. Stanescu Jan 2017

Tunneling Conductance In Semiconductor-Superconductor Hybrid Structures, John Stenger, Tudor D. Stanescu

Faculty & Staff Scholarship

No abstract provided.

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Unusual Enhancement Of Effective Magnetic Anisotropy With Decreasing Particle Size In Maghemite Nanoparticles, K. L. Pisane, Sobhit Singh, M. S. Seehra Jan 2017

Unusual Enhancement Of Effective Magnetic Anisotropy With Decreasing Particle Size In Maghemite Nanoparticles, K. L. Pisane, Sobhit Singh, M. S. Seehra

Faculty & Staff Scholarship

In magnetic nanoparticles (NPs), the observed increase in the effective magnetic anisotropy Keff with the decrease in particle size D is often interpreted, sometimes unsuccessfully, using the equation Keff = Kb + (6KS/D), where Kb is the bulk-like anisotropy of the core spins and KS is the anisotropy of spins in the surface layer. Here, we test the validity of this relation in γ-Fe2O3 NPs for sizes D from 15 nm to 2.5 nm. The samples include oleic acid-coated NPs with D = 2.5, 3.4, 6.3, and 7.0 nm investigated here, with results on 14 other sizes taken from literature. …

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Probing Microplasticity In Small-Scale Fcc Crystals Via Dynamic Mechanical Analysis, Xiaoyue Ni, Stefanos Papanikolaou, Gabriele Vajente, Rana X Adhikari, Julia R. Greer Jan 2017

Probing Microplasticity In Small-Scale Fcc Crystals Via Dynamic Mechanical Analysis, Xiaoyue Ni, Stefanos Papanikolaou, Gabriele Vajente, Rana X Adhikari, Julia R. Greer

Faculty & Staff Scholarship

In small-scale metallic systems, collective dislocation activity has been correlated with size effects in strength and with a steplike plastic response under uniaxial compression and tension. Yielding and plastic flow in these samples is often accompanied by the emergence of multiple dislocation avalanches. Dislocations might be active preyield, but their activity typically cannot be discerned because of the inherent instrumental noise in detecting equipment. We apply alternate current load perturbations via dynamic mechanical analysis during quasistatic uniaxial compression experiments on single crystalline Cu nanopillars with diameters of 500 nm and compute dynamic moduli at frequencies 0.1, 0.3, 1, and 10 …

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The Nonhomogeneous Poisson Process For Fast Radio Burst Rates, Earl Lawrence, Scott Vander Wiel, Casey Law, Sarah Burke Spolaor, Geoffrey C. Bower Jan 2017

The Nonhomogeneous Poisson Process For Fast Radio Burst Rates, Earl Lawrence, Scott Vander Wiel, Casey Law, Sarah Burke Spolaor, Geoffrey C. Bower

Faculty & Staff Scholarship

This paper presents the non-homogeneous Poisson process (NHPP) for modeling the rate of fast radio bursts (FRBs) and other infrequently observed astronomical events. The NHPP, well-known in statistics, can model changes in the rate as a function of both astronomical features and the details of an observing campaign. This is particularly helpful for rare events like FRBs because the NHPP can combine information across surveys, making the most of all available information. The goal of the paper is two-fold. First, it is intended to be a tutorial on the use of the NHPP. Second, we build an NHPP model that …

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Puncture Initial Data For Black-Hole Binaries With High Spins And High Boosts, Ian Ruchlin, James Healy, Carlos O. Lousto, Yosef Zlochower Jan 2017

Puncture Initial Data For Black-Hole Binaries With High Spins And High Boosts, Ian Ruchlin, James Healy, Carlos O. Lousto, Yosef Zlochower

Faculty & Staff Scholarship

We solve the Hamiltonian and momentum constraints of general relativity for two black-holes with nearly extremal spins and relativistic boosts in the puncture formalism. We use a non-conformally-flat ansatz with an attenuated superposition of two Lorentz-boosted, conformally-Kerr or conformally-Schwarzschild 3-metrics and their corresponding extrinsic curvatures. We compare evolutions of these data with the standard Bowen-York conformally-flat ansatz (technically limited to intrinsic spins \(\chi=S/M^2_{\text{ADM}}=0.928\) and boosts \(P/M_{\text{ADM}}=0.897\)), finding, typically, an order of magnitude smaller burst of spurious radiation and agreement with inspiral and merger. As a first case study, we evolve two equal-mass black-holes from rest with an initial separation of …

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Evolutions Of Nearly Maximally Spinning Black Hole Binaries Using The Moving Puncture Approach, Yosef Zlochower, James Healy, Carlos O. Lousto, Ian Ruchlin Jan 2017

Evolutions Of Nearly Maximally Spinning Black Hole Binaries Using The Moving Puncture Approach, Yosef Zlochower, James Healy, Carlos O. Lousto, Ian Ruchlin

Faculty & Staff Scholarship

No abstract provided.

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A Radio Relic And A Search For The Central Black Hole In The Abell 2261 Brightest Cluster Galaxy, Sarah Burke-Spolaor, Kayhan Gültekin, Marc Postman, Tod R. Lauer, Joanna M. Taylor, T. Joseph W. Lazio, Leonidas A. Moustakas Jan 2017

A Radio Relic And A Search For The Central Black Hole In The Abell 2261 Brightest Cluster Galaxy, Sarah Burke-Spolaor, Kayhan Gültekin, Marc Postman, Tod R. Lauer, Joanna M. Taylor, T. Joseph W. Lazio, Leonidas A. Moustakas

Faculty & Staff Scholarship

We present VLA images and HST/STIS spectra of sources within the center of the brightest cluster galaxy (BCG) in Abell 2261. These observations were obtained to test the hypothesis that its extremely large, flat core reflects the ejection of its supermassive black hole. Spectra of three of the four most luminous "knots" embedded in the core were taken to test whether one may represent stars bound to a displaced massive black hole. The three knots have radial velocity offsets dV < ~150 km/s from the BCG. Knots 2 and 3 show kinematics, colors, and stellar masses consistent with infalling low-mass galaxies or larger stripped cluster members. Large errors in the stellar velocity dispersion of Knot 1, however, mean that we cannot rule out the hypothesis that it hosts a high-mass black hole. A2261-BCG has a compact, relic radio-source offset by 6.5 kpc (projected) from the optical core's center, but no active radio core that would pinpoint the galaxy's central black hole to a tight 10 GHz flux limit 48 Myr ago, with an equipartition condition magnetic field of 15 uG. These observations are still consistent with the hypothesis that the nuclear black hole has been ejected from its core, but the critical task of locating the supermassive black hole or demonstrating that A2261-BCG lacks one remains to be done.

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Unifying The Visible And Passive Infrared Bands: Homogeneous And Heterogeneous Multi-Spectral Face Recognition, Nnamdi C. Osia Jan 2017

Unifying The Visible And Passive Infrared Bands: Homogeneous And Heterogeneous Multi-Spectral Face Recognition, Nnamdi C. Osia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Face biometrics leverages tools and technology in order to automate the identification of individuals. In most cases, biometric face recognition (FR) can be used for forensic purposes, but there remains the issue related to the integration of technology into the legal system of the court. The biggest challenge with the acceptance of the face as a modality used in court is the reliability of such systems under varying pose, illumination and expression, which has been an active and widely explored area of research over the last few decades (e.g. same-spectrum or homogeneous matching). The heterogeneous FR problem, which deals with …

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An Evaluation Of The Effects Of Treatment Integrity Errors On Skill Acquisition During Discrete-Trial Instruction, Jennifer M. Owsiany Jan 2017

An Evaluation Of The Effects Of Treatment Integrity Errors On Skill Acquisition During Discrete-Trial Instruction, Jennifer M. Owsiany

Graduate Theses, Dissertations, and Problem Reports (ETD)

Previous research has demonstrated that delivering controlling prompts and reinforcers with low-levels of treatment integrity may interfere with the acquisition of skills during discrete-trial instruction. However, implementing certain components of discrete-trial instruction with varying levels of low integrity may influence skill acquisition differently. In Experiment 1, we evaluated the effects of delivering a prompt following participants' incorrect responses with 25%, 50%, 75%, and 100% integrity on skill acquisition with two children with autism spectrum disorder. In Experiment 2, we evaluated the effects of delivering a reinforcer following participants' correct responses with 25%, 50%, 75%, and 100% integrity on skill acquisition …

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Geotechnical Laboratory Testing For 2-D Fem Analysis Of Geomorphic And Planar Sloped Caps And Covers For Sustainable Mine Refuse Deposition, Sun Hee Park Jan 2017

Geotechnical Laboratory Testing For 2-D Fem Analysis Of Geomorphic And Planar Sloped Caps And Covers For Sustainable Mine Refuse Deposition, Sun Hee Park

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis reports the findings of the application of Geomorphic Landform Design principles to the Royal Scot abandoned coarse coal refuse (CCR) pile located in Greenbrier County, West Virginia. The Royal Scot facility has many environmental concerns including severe erosion, acid-mine/rock drainage, and sediment transport. A cap and cover system is proposed to be implemented which incorporates the GLD principles. A two-layer cap and cover system will be used to reclaim the site and return it back to a stable state and reduce the production of acid-mine drainage. The system is composed of a hydraulic barrier composed of compacted CCR, …

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Finite Element Simulation Of Large-Scale Confined Inflatable Structures, Iole Pecora Jan 2017

Finite Element Simulation Of Large-Scale Confined Inflatable Structures, Iole Pecora

Graduate Theses, Dissertations, and Problem Reports (ETD)

The protection of transportation tunnels is one of the top priorities of transportation and government entities. Transportation tunnels have been identified as particularly vulnerable to different threats such as propagation of toxic gasses, or smoke originated by human activities or flooding originated by extreme climatic events such as hurricanes and severe weather. Finding solutions to minimize the consequences of disastrous events has become critical to increase the resiliency of tunnel systems. The implementation of large-scale inflatable structures at specific locations of the tunnel system for containing the propagation of flooding or gases is now possible. When a threat happens, a …

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Historical Phenology Of West Virginia: 130 Years Of Spring Avian Migration And Wildflower Blooming, Lori M. Petrauski Jan 2017

Historical Phenology Of West Virginia: 130 Years Of Spring Avian Migration And Wildflower Blooming, Lori M. Petrauski

Graduate Theses, Dissertations, and Problem Reports (ETD)

Phenology, or the study of biological cycles in relation to the seasons, is a useful approach to study climate change and its effects on species. Analyzing historical records of phenology can give clues to understanding the future of ecosystems in relation to climate change. Specifically, using untapped sources of historical phenological data such as museum specimens, journals written by nature-minded citizens, and dated photographs can expand our temporal range of phenology data and provide a baseline with which to compare current phenology observations.;There is no central database for historical phenology data in West Virginia and there has been little research …

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Three Essays On State And Federal Regulations, Shree Baba Pokharel Jan 2017

Three Essays On State And Federal Regulations, Shree Baba Pokharel

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation consists of three essays on state and federal regulations in the US. Each paragraph below refers to the three abstracts for the three chapters in this dissertation, respectively.;Given the growing importance of the wine industry in the US, wine special interests are on the rise. Data shows that campaign contributions from the wine industry to officials running for state offices have increased over time. Given this reality, one can expect wine excise tax to remain low in states that receive higher campaign contributions. In addition, there are theoretical and empirical reasons to believe that these tax rates are …

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Improving Seeding And Mulching Specifications In West Virginia And Creating A Materials Estimate Tool, Forrest N. Pritt Jan 2017

Improving Seeding And Mulching Specifications In West Virginia And Creating A Materials Estimate Tool, Forrest N. Pritt

Graduate Theses, Dissertations, and Problem Reports (ETD)

Vegetation is established following construction through various seeding and mulching practices. Environmental permits in West Virginia require a minimum of 70% of ground cover by area for release of a construction site. The West Virginia Division of Highways (WVDOH), like many other states, has specifications for temporary and permanent seeding and mulching practices. This research critically evaluated the best management practices (BMPs) utilized in the WVDOH specifications, developed recommended revisions to the specifications, and created supplemental materials for future application.;Recommended revisions to the WVDOH include: topsoil, improved soil tests, rolled erosion control products (RECPs), biological growth stimulants (BGSs), hydraulic growth …

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Prediction Of Maximum Scour Depth Using Scaled Down Bridge Model In A Laboratory, Rupayan Saha Jan 2017

Prediction Of Maximum Scour Depth Using Scaled Down Bridge Model In A Laboratory, Rupayan Saha

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recently, United States faced catastrophic flooding in West Virginia, Texas, Louisiana, Oklahoma, and Arkansas, and the flooding resulted in several bridge failures. Among them, Bridge scour is one of the main causes of many bridge failures, and leads to financial losses as well as loss of life. Since 1960, a lot of scour research has been completed and several estimation methods were already in the hand of hydraulic engineers. However, scouring is still a challenging topic. Currently, the issues of scour are once again rising because the occurrence of extreme weather events are expected to increase in frequency. Furthermore, current …

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Three Essays On Corruption, Sumi Sharma Jan 2017

Three Essays On Corruption, Sumi Sharma

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation examines the link between market competition and corruption for developing countries and top income inequality and corruption in the US. The first two chapters explore the link between firm-level markup and corruption for a global dataset. I test the hypothesis that high-markup firms are less likely to engage in corruption. To investigate this relationship, I use firm-level data from World Bank Enterprise Survey (WBES) for 95 developing countries from 10 manufacturing industries. I find that high markup firms that operate in less competitive environments are less likely to bribe. These results are robust across three other measures of …

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Cardiac And Mitochondrial Dysfunction During Diabetes Mellitus: Examination Of Mitochondrial Import Mechanisms, Danielle Lee Shepherd Jan 2017

Cardiac And Mitochondrial Dysfunction During Diabetes Mellitus: Examination Of Mitochondrial Import Mechanisms, Danielle Lee Shepherd

Graduate Theses, Dissertations, and Problem Reports (ETD)

Approximately 9% of the United States population is diagnosed with diabetes mellitus (DM), which is comprised of 2 distinct pathologies: type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). T1DM, which is caused by insufficient insulin production, affects approximately 5% of diabetic patients, while T2DM results from insulin resistance and affects 95% of all diabetic patients. Within diabetic patients, cardiac complications, such as diabetic cardiomyopathy, are the leading cause of morbidity and mortality. The mitochondrion has been implicated as an underlying factor in the etiology and progression of the cardiac contractile deficits and cardiac failure that accompany DM. …

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Subspace Representations And Learning For Visual Recognition, Farzad Siyahjani Jan 2017

Subspace Representations And Learning For Visual Recognition, Farzad Siyahjani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pervasive and affordable sensor and storage technology enables the acquisition of an ever-rising amount of visual data. The ability to extract semantic information by interpreting, indexing and searching visual data is impacting domains such as surveillance, robotics, intelligence, human- computer interaction, navigation, healthcare, and several others. This further stimulates the investigation of automated extraction techniques that are more efficient, and robust against the many sources of noise affecting the already complex visual data, which is carrying the semantic information of interest. We address the problem by designing novel visual data representations, based on learning data subspace decompositions that are invariant …

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Design, Construction, And Analysis Of A Pilot-Scale Automated Drilling Platform, Cody Smith Jan 2017

Design, Construction, And Analysis Of A Pilot-Scale Automated Drilling Platform, Cody Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

This project and the associated research investigates automation techniques for drilling operations, along with the analysis involved in building an automated pilot-scale drilling platform. The outcome from this research investigates feasible technologies and techniques that can be used to automate a pilot-scale drilling rig, with the intent that these practices may provide insight into the construction or procedures of full scale rigs. Both the theory and lab exercise components of this research were completed in association with the Drillbotics competition sponsored by the Drilling Systems Automation Technical Section (DSATS) committee of the Society of Petroleum Engineers (SPE). This study includes …

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A New Compactification For Celestial Mechanics, Daniel Solomon Jan 2017

A New Compactification For Celestial Mechanics, Daniel Solomon

Graduate Theses, Dissertations, and Problem Reports (ETD)

This is an exposition of a new compactification of Euclidean space enabling the study of trajectories at and approaching spatial infinity, as well as results obtained for polynomial differential systems and Celestial Mechanics. The Lorenz system has an attractor for all real values of its parameters, and almost all of the complete quadratic systems share an interesting feature with the Lorenz system.;Informed by these results, the main theorem is established via a contraction mapping arising from an integral equation derived from the Celestial Mechanics equations of motion. We establish the existence of an open set of initial conditions through which …

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Clarifying Resource Dependence: A Multi-Dimensional Approach To Dependence And Autonomy In Entrepreneurial Firms, Curtis R. Sproul Jan 2017

Clarifying Resource Dependence: A Multi-Dimensional Approach To Dependence And Autonomy In Entrepreneurial Firms, Curtis R. Sproul

Graduate Theses, Dissertations, and Problem Reports (ETD)

Entrepreneurial firms face dependence on other firms in the external environment to access resources critical for the development and survival of the firm. While substantial research has examined resource dependence and how firms may remedy such dependencies, the literature often fails to acknowledge key factors that can predict and explain firm behavior and outcomes in such situations. Firms are shown to enter into inter-organizational relationships in order to remedy resource dependencies, but studies typically evaluate such relationships according to their structure, rather than the resource being sought. Research also frequently ignores the role of autonomy in resource dependence. As gaining …

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Endoplasmic Reticulum Stress Is Transmissible Among Cells Of The Central Nervous System, Neil T. Sprenkle Jan 2017

Endoplasmic Reticulum Stress Is Transmissible Among Cells Of The Central Nervous System, Neil T. Sprenkle

Graduate Theses, Dissertations, and Problem Reports (ETD)

Improper protein folding and trafficking are common pathological events observed in various cell types in neurodegenerative diseases. If the protein quality control mechanisms of the endoplasmic reticulum (ER) fail to re-establish proteostasis, misfolded proteins accumulate within the lumen of the ER and perturb normal cellular processes. While low-level stimulation of the unfolded protein response (UPR) is considered a beneficial physiological response to transient protein misfolding stress, or ER stress, sustained UPR activation resulting from prolonged ER stress can promote neurotoxicity. The cell-autonomous mechanisms of the UPR have been extensively characterized in the context of neuropathology. Nevertheless, there still remain unanswered …

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Comparing The Hydrodynamic Response Of Fracture Shearing In Marcellus And Eau Claire Shales, Matthew A. Stadelman Jan 2017

Comparing The Hydrodynamic Response Of Fracture Shearing In Marcellus And Eau Claire Shales, Matthew A. Stadelman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Three samples of Marcellus and Eau Claire shales were sheared in a modified Hassler style core holder. Before testing and after each shear step, the hydraulic transmissivity was measured and a high-resolution 3-D image taken using a computer tomography (CT) scanner, resolution ranged from 26.7 to 27.6 microns. Each sample was sheared four to eight times during a test providing a total of 37 fracture geometries. The 3-D binary images of each fracture were processed based on a voxel connectivity graph, removing any clusters that were not connected to the main fracture. Two-dimensional aperture maps were then generated by flattening …

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Radial Growth Patterns In Trees Surviving Canopy Gap Disturbances, Ruth A. Stetler Jan 2017

Radial Growth Patterns In Trees Surviving Canopy Gap Disturbances, Ruth A. Stetler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Forest disturbance regimes in eastern North America have long been conceptualized as localized gap disturbances, but recent studies suggest that more widespread, infrequent disturbance events may also be important. However, uncertainties in tree-ring methods used to detect disturbance, and in the factors that drive growth release of trees, limit the conclusions that can be drawn from regional disturbance analyses. I designed a study to further elucidate forest disturbance dynamics in eastern North America by using two approaches: 1) a case study examining the sensitivity of the radial growth averaging method of detecting disturbance and the factors influencing detection of a …

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