Digital Commons Network^™

Investigation Of Thermal Stress Degradation In Indium-Gallium-Zinc-Oxide Tfts, Prashant Ganesh

Theses

The performance of IGZO TFTs has improved significantly in recent years, however device stability still remains a significant issue. Thermal stability of IGZO TFTs be- comes very crucial to ensure desired performance of end-product. Both bottom-gate (BG) and double-gate (DG) TFTs were observed to degrade with hotplate treatments under 200◦C. Such events are rarely reported in the literature, and thus became the primary focus of this work. The mechanism causing the instability is not completely understood, however experimental results indicate the instability occurs either di- rectly or indirectly due to the influence of H2O within the passivation oxide above the …

Computational Fluid Dynamics Analysis Of Blalock-Taussig Shunt, Thomas Hess, Ramesh K. Agarwal

Mechanical Engineering and Materials Science Independent Study

Blalock-Taussig or BT shunts are a surgical procedure performed on infants suffering from cyanosis or “Blue Baby Syndrome.” Cyanosis refers the purple or blue color of the skin resulting from low blood oxygen saturation. A BT shunt is an artificial vessel placed between the right ventricle and the pulmonary artery to increase lung blood flow and blood oxygen saturation levels.During this independent study, the flow of blood through several different BT shunt configurations was analyzed using ANSYS Fluent, a Computational Fluid Dynamics (CFD) software analysis tool.Data from each shunt analysis was when compared to help determine the shunt parameters and …

Potential Graft Materials For Acl Reconstruction Surgery, Matthew Jenkins, Spencer Lake

Mechanical Engineering and Materials Science Independent Study

No abstract provided.

Expression Of Wnt-Signaling Pathway Genes And Their Associations With Mirnas In Colorectal Cancer, Martha L. Slattery, Lila E. Mullany, Lori C. Sakoda, Wade S. Samowitz, Roger K. Wolff, John R. Stevens, Jennifer S. Herrick

Mathematics and Statistics Faculty Publications

The Wnt-signaling pathway functions in regulating cell growth and thus is involved in the carcinogenic process of several cancers, including colorectal cancer. We tested the hypothesis that multiple genes in this signaling pathway are dysregulated and that miRNAs are associated with these dysregulated genes. We used data from 217 colorectal cancer (CRC) cases to evaluate differences in Wnt-signaling pathway gene expression between paired CRC and normal mucosa and identify miRNAs that are associated with these genes. Gene expression data from RNA-Seq and miRNA expression data from Agilent Human miRNA Microarray V19.0 were analyzed. We focused on genes most strongly associated …

Does Plasticity In Thermal Tolerance Trade Off With Inherent Tolerance? The Influence Of Setal Tracheal Gills On Thermal Tolerance And Its Plasticity In A Group Of European Diving Beetles., W. C.E.P. Verberk, P. Calosi, J. I. Spicer, S. Kehl, D. T. Bilton

School of Biological and Marine Sciences

In the face of global warming, both the absolute thermal tolerance of an ectotherms, and its ability to shift its tolerance level via acclimation, are thought to be fundamentally important. Understanding the links between tolerance and its plasticity is therefore critical to accurately predict vulnerability to warming. Previous studies in a number of ectotherm taxa suggest trade-offs in the evolution of thermal tolerance and its plasticity, something which does not, however, apply to Deronectes diving beetles, where these traits are instead positively correlated. Here we revisit the relationship between thermal tolerance and plasticity in these beetles, paying attention to a …

Migrating Selves: Counteracting An Unwelcoming Ethos Of Reception, Saloshna Vandeyar Phd, Thirusellvan Vandeyar Phd

Societies Without Borders

Utilising the research methodology of narrative inquiry, this study set out to explore how Nigerian immigrant academics counteracted an unwelcoming ethos of reception at a South African university. Data capture comprised a mix of semi-structured interviews, observations, field notes and a researcher journal. Data was analysed utilising qualitative content analysis. Findings reveal that the resiliency process of Nigerian immigrant academics was triggered by ecological sources within the context of the academe and surfaced in the form of resilient qualities. Nigerian immigrant academics drew on specific internal assets and external resources to circumvent the effects of various stressors as well as …

One Community, One Family, Eric F. Spina

President's Blog: From the Heart

While the University of Dayton is a committed Catholic, Marianist university, we recognize that we don't all share the same faith or cultural traditions. Many of us grew up in diverse towns and cultures ? from Chicago and St. Henry to Riyadh and San Juan. Yet, we are one community, one family.

Evaluating The Effectiveness Of Two Teaching Strategies On Nursing Students Knowledge Skills And Attitudes Of Quality Improvement And Safety, Karen Maxwell

Dissertations

In 1999, the Institute of Medicine published a report To Err Is Human: Building a Safer Health System, which found that 44,000-98,000 people die as a result of preventable medical errors each year. Following this report in 2005, the Quality and Safety for Nurses (QSEN) project was established which defined a set of six core competencies that all nursing students should possess at graduation. Since the IOM report and the establishment of QSEN, nurse educators have been challenged with discovering effective teaching strategies to infuse the QSEN competencies into the nursing curricula. The purpose of the quantitative, pretest/post-test control group …

Wind Is Nebraska’S Future, With Or Without The Clean Power Plan, Megan Pamperin

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

The Clean Power Plan was issued in October 2015. President Trump called for a review of the plan this March and on October 16^th, 2017 the EPA released a proposal to repeal it. The Clean Power Plan would have reduced Nebraska’s state emissions to 22,250,000 tons of carbon dioxide by 2024, down by about 5 million tons compared to 2012 emissions.¹ The new projection for 2020 without the plan is 34 million tons of CO₂ emitted.

Coal and other fossil fuel energy sources are the main culprits of these carbon emissions, and here in Nebraska coal …

Modifications To Commercial Printers To Enable Multi-Material Fabrication Of 3d Cellular Scaffolds, Lucas D. Albrecht

Theses - ALL

The scarcity of organs for patients that need transplants has led to exceedingly

lengthy waits for organ transplants for sick patients. Fabrication of tissues and organ

constructs in-vitro has potential to end the shortage, however many of the machines

used to create these tissues and organs are expensive, not easy to use, and do not

have any further practical applications. Bioprinting technology has the potential to

revolutionize the fabrication of biological constructs that can be used as in vitro model

tissues and vivo substitutes. Bioprinting is the process of using conventional 3D printing

methods and computer-aided-design (CAD) to create patient …

Coast Guard Public Affairs Middle Management And The Excellence Study, Stephen Bailey Lehmann

Theses - ALL

As is the nature of any organization, the U.S. Coast Guard is constantly seeking to improve its functions, operations, policies and procedures. In terms of communications, the service’s Public Affairs Program has instituted a number of different competencies and qualifications to better prepare candidates as they approach the next rank. This study sought to provide an outline of the middle-management component as it exists within the public affairs element and compare the findings to those published in the Excellence Study to assist the service by providing a basis from which additional policy recommendations could be made.

The study was conducted …

Cell Laden Hydrogel Microspheres Using 3d Printed Microfluidics, Sanika Nitin Suvarnapathaki

Theses - ALL

Cell laden hydrogel microspheres using 3D printed microfluidics

Abstract

By

Sanika Suvarnapathaki

Current tissue engineering therapies use macro-scale three dimensional (3D) scaffolds to treat tissue defects surgically. Uneven cell seeding and oxygen and media perfusion cause low cell viability in these macro-scale scaffolds. Microencapsulation, a technique of encapsulating cells in biocompatible polymers or hydrogels, has the potential to address these key issues, and therefore this technology has been used for numerous healthcare applications over the last two decades. Cell microencapsulation in hydrogels that mimic the tissue physiology and biochemistry has made it possible to use natural hydrogels like gelatin methacrylate …

The Political Economy Of Resource Conflicts And Forced Migration: Why Afghanistan, Colombia And Sudan Are The World's Longest Forced Migration, Tarique Niazi Phd, Jeremy Hein Phd

Societies Without Borders

Afghanistan, Colombia, and Sudan are the world’s three longest producers of refugees and internally displaced persons (IDPs). Why? To answer this question, we evaluate the conventional and dominant geopolitical model of forced migration, as well as alternative models that focus on resource-based conflicts and political economy. We demonstrate that in each of the three cases, natural resources are at the heart of the conflicts that precede the involuntary movement of people both across international borders (refugees) and within national borders (IDPs). But the presence of resources by itself does not cause conflicts or forced migration. In Afghanistan, Colombia and Sudan, …

Electromyography Exposes Heterogeneity In Muscle Co-Contraction Following Stroke, Caitlin L. Banks, Helen J. Huang, Virginia L. Little, Carolynn Patten

PT Faculty Publications

Walking after stroke is often described as requiring excessive muscle co-contraction, yet, evidence that co-contraction is a ubiquitous motor control strategy for this population remains inconclusive. Co-contraction, the simultaneous activation of agonist and antagonist muscles, can be assessed with electromyography (EMG) but is often described qualitatively. Here, our goal is to determine if co-contraction is associated with gait impairments following stroke. Fifteen individuals with chronic stroke and nine healthy controls walked on an instrumented treadmill at self-selected speed. Surface EMGs were collected from the medial gastrocnemius (MG), soleus (SOL), and tibialis anterior (TA) of each leg. EMG envelope amplitudes were …

Concise Review: Translating Regenerative Biology Into Clinically Relevant Therapies: Are We On The Right Path?, Jennifer Simkin, Ashley W. Seifert

Biology Faculty Publications

Despite approaches in regenerative medicine using stem cells, bio-engineered scaffolds, and targeted drug delivery to enhance human tissue repair, clinicians remain unable to regenerate large-scale, multi-tissue defects in situ. The study of regenerative biology using mammalian models of complex tissue regeneration offers an opportunity to discover key factors that stimulate a regenerative rather than fibrotic response to injury. For example, although primates and rodents can regenerate their distal digit tips, they heal more proximal amputations with scar tissue. Rabbits and African spiny mice re-grow tissue to fill large musculoskeletal defects through their ear pinna, while other mammals fail to regenerate …

Detection, Diagnosis And Mitigation Of Malicious Javascript With Enriched Javascript Executions, Xunchao Hu

Dissertations - ALL

Malicious JavaScript has become an important attack vector for software exploitation attacks and imposes a severe threat to computer security. In particular, three major class of problems, malware detection, exploit diagnosis, and exploits mitigation, bring considerable challenges to security researchers. Although a lot of research efforts have been made to address these threats, they have fundamental limitations and thus cannot solve the problems.

Existing analysis techniques fall into two general categories: static analysis and dynamic analysis. Static analysis tends to produce inaccurate results (both false positive and false negative) and is vulnerable to a wide series of obfuscation techniques. Thus, …

Gas Phase Oxidation Of Levulinic Acid For The Production Of Maleic Anhydride Over Supported Vanadium Oxide Catalysts, Anargyros Chatzidimitriou

Dissertations - ALL

With continued depletion of fossil carbon, there is a need to utilize renewable sources of energy and consumer end products. In this context, we examine the aerobic oxidation of levulinic acid, a bio-based platform chemical derived from lignocellulosic biomass, to produce maleic anhydride, a valuable commodity chemical. This process is carried out over supported vanadium oxide catalysts. Yields as high as 71% of the theoretical maximum were achieved at 573 K over a vanadium oxide catalyst supported on SiO2. The exact mechanism underlying this transformation is complex, but our results suggest that maleic anhydride forms by the oxidative cleavage of …

Oxygen Transport Membrane Reactors For Oxy-Fuel Combustion And Carbon Capture Purposes, Ryan Falkenstein-Smith

Dissertations - ALL

This thesis investigates oxygen transport membrane reactors (OTMs) for the application of oxy-fuel combustion. This is done by evaluating the material properties and oxygen permeability of different OTM compositions subjected to a variety of operating conditions. The scope of this work consists of three components: (1) evaluate the oxygen permeation capabilities of perovskite-type materials for the application of oxy-fuel combustion; (2) determine the effects of dual-phase membrane compositions on the oxygen permeation performance and membrane characteristics; and (3) develop a new method for estimating the oxygen permeation performance of OTMs utilized for the application of oxy-fuel combustion.

SrSc0.1Co0.9O3-δ (SSC) is …

Investigating The Interaction Of A Supersonic Single Expansion Ramp Nozzle And Sonic Wall Jet, Matthew Berry

Dissertations - ALL

For nearly 80 years, the jet engine has set the pace for aviation technology around the world. Complexity of design has compounded upon each iteration of nozzle development, while the rate of fundamental fluids knowledge struggles to keep up. The increase in velocities associated with supersonic jets, have exacerbated the need for flow physics research. Supersonic flight remains the standard for military aircraft and is being rediscovered for commercial use. With the addition of multiple streams, complex nozzle geometries, and airframe integration in modern aircraft, the flow physics rapidly become more difficult. As performance capabilities increase, so do the noise …

Ensemble Methods For Anomaly Detection, Zhiruo Zhao

Dissertations - ALL

Anomaly detection has many applications in numerous areas such as intrusion detection, fraud detection, and medical diagnosis. Most current techniques are specialized for detecting one type of anomaly, and work well on specific domains and when the data satisfies specific assumptions.

We address this problem, proposing ensemble anomaly detection techniques that perform well in many applications, with four major contributions: using bootstrapping to better detect anomalies on multiple subsamples, sequential application of diverse detection

algorithms, a novel adaptive sampling and learning algorithm in which the anomalies are iteratively examined, and improving the random forest algorithms for detecting anomalies in streaming …

Design, Synthesis And Study Of Thermomechanically Active Polymer Networks Based On Latent Crosslinking Of Semicrystalline Polymers, Wenbin Kuang

Dissertations - ALL

Demand has arisen rapidly for smart materials in the world of the need to develop and understand new functional products like plastics, rubber, adhesives, fibers, and coatings. Such products are essentially composed of polymers, large molecules of high molecular weight with homogeneous or various repeating units, which researchers term “macromolecules” that engender specific structural, morphological, and physical and mechanical properties. Those polymers with the capacity to change their configuration in accordance with environmental alteration are specifically referred to as shape memory polymers (SMPs), attracting much interest of study both academically and industrially. Herein, this dissertation aims at design, fabrication, and …

Adsorption Of Iodine And Water On Silver-Exchanged Mordenite, Yue Nan

Dissertations - ALL

The reprocessing of used nuclear fuel to recover the fissile materials generates off gases including radioactive nuclides namely 3H (tritiated water, H3HO), 129I, 85Kr, 135Xe, and 14C. Due to its high quantity in off-gas streams and long half-life (1.59 million years), 129I removal from the off-gas streams is a significant objective of off-gas treatment.

129I retention by solid adsorbents was recognized a better strategy in comparison to liquid scrubbers due to the simplicity of system design and low cost. Among the studied adsorbents, reduced silver-exchanged mordenite (Ag0Z) was widely recognized as the state-of-art adsorbent for iodine removal. It has been …

Vortex Detection And Tracking In Massively Separated And Turbulent Flows, Yangzi Huang

Dissertations - ALL

The vortex produced at the leading edge of the wing, known as the leading edge vortex (LEV), plays an important role in enhancing or destroying aerodynamic force, especially lift, upon its formation or shedding during the flapping flight of birds and insects. In this thesis, we integrate multiple new and traditional vortex identification approaches to visualize and track the LEV dynamics during its shedding process. The study is carried out using a 2D simulation of a flat plate undergoing a 45 degree pitch-up maneuver. The Eulerian 𝛤1 function and 𝑄 criterion are used along with the Lagrangian coherent structures (LCS) …

Catalytic Synthesis Of Biodiesel Fuel Under Sub/Supercritical Conditions: Kinetics And Phase Behavior, Jiuxu Liu

Dissertations - ALL

In this thesis, transesterification of triglycerides and esterification of free fatty acids were executed under subcritical and supercritical alcohol conditions, and discussed in Chapter 2-5. The project was initiated by studying the phase behavior and kinetics of transesterification reactions under severe reaction conditions (T: 300-400 oC, P=200 bar), since those conditions were suggested and commonly used in the literature. At these conditions, triglycerides reacted with alcohol within minutes, and the oil-alcohol mixture formed a homogeneous phase which minimized the boundary mass transfer resistance. The composition change of the reaction mixture made the critical point of the system approach supercritical region …

Design Of Tribologically Enhanced Polymeric Materials For Biomedical Applications, Allen Osaheni

Dissertations - ALL

Anytime two surfaces are in normal contact, accompanied by tangential motion, there is potential for deterioration of one or both surfaces. Gradual wear, or the removal of surface material, is typically an undesirable event. Therefore, the need for lubrication arises to minimize the amount of shear stress that develops between opposing surfaces. This reduction in shear stress is characterized by the coefficient of friction (COF). Friction is one of the primary subjects of interest in tribology, the science of the friction and wear of articulating surfaces.

A number of fascinating tribological systems can be found in nature. One example which …

Rectangular Waveguide Filled With Uniaxial Medium And Negative Resistance Enhanced Composite Right/Left-Handed Transmission Line, Kepei Sun

Dissertations - ALL

Two wave-guiding problems are treated in this work. The first part addresses the problem of a rectangular waveguide filled with a uniaxially anisotropic or uniaxial medium. Different orientations of the optic axis of the uniaxial medium are considered and the wave transmission and modal behaviors are investigated. When the optic axis is aligned with one of the coordinate axes, i. e., x, y, or z axis, the method of wave decomposition with respect to the optic axis orientation is proposed and the complete analytic solutions are presented and compared with conventional transverse-to-z solutions. When the optic axis is tilted but …

Legal Studies Offers 3+3 Option With School Of Law, Sarah Sapp

University of Mississippi News

Paralegal studies enhances program, adds new fast-track to Juris Doctorate

Development And Evaluation Of A Connective Tissue Phantom Model For Subsurface Visualization Of Cancers Requiring Wide Local Excision, Kimberly S. Samkoe, Brent D. Bates, Niki N. Tselepidakis, Alisha V. Dsouza, Jason R. Gunn, Dipak B. Ramkumar, Keith D. Paulsen, Brian W. Pogue, Eric R. Henderson

Dartmouth Scholarship

Wide local excision (WLE) of tumors with negative margins remains a challenge because surgeons cannot directly visualize the mass. Fluorescence-guided surgery (FGS) may improve surgical accuracy; however, conventional methods with direct surface tumor visualization are not immediately applicable, and properties of tissues surrounding the cancer must be considered. We developed a phantom model for sarcoma resection with the near-infrared fluorophore IRDye 800CW and used it to iteratively define the properties of connective tissues that typically surround sarcoma tumors. We then tested the ability of a blinded surgeon to resect fluorescent tumor-simulating inclusions with ∼1-cm margins using predetermined target fluorescence intensities …

Growing Pains: The Transformative Journey From A Nascent To A Formal Not-For-Profit Venture, Avery C. Edenfield, Fredrik O. Andersson

English Faculty Publications

This article examines how a social venture transitions from nascent to formal status and argues that the transformation of the organization set in motion by establishing formal boundaries is a deeply profound one. Drawing from the nonprofit and social entrepreneurship literature on what prompts and energizes individuals to initiate new not-for-profit ventures, and linking it to a notion of revolutionary crisis as organizations emerge and develop, we seek to illuminate and explore the tension, and its consequences, between nonprofit entrepreneurs and the organization they create as the new venture transitions from nascent to formal. We do this by presenting the …

Structural Evidence Of A Major Conformational Change Triggered By Substrate Binding In Dape Enzymes: Impact On The Catalytic Mechanism, Boguslaw Nocek, Cory Reid, Anna Starus, Tahirah Heath, David Bienvenues, Jerzy Osipiuk, Robert Jedrzeczak, Andrzej Joachimiak, Daniel P. Becker Ph.D., Richard C. Holz

Chemistry: Faculty Publications and Other Works

The X-ray crystal structure of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase from Haemophilus influenzae (HiDapE) bound by the products of hydrolysis, succinic acid and l,l-DAP, was determined at 1.95 Å. Surprisingly, the structure bound to the products revealed that HiDapE undergoes a significant conformational change in which the catalytic domain rotates ∼50° and shifts ∼10.1 Å (as measured at the position of the Zn atoms) relative to the dimerization domain. This heretofore unobserved closed conformation revealed significant movements within the catalytic domain compared to that of wild-type HiDapE, which results in effectively closing off access to …