Digital Commons Network^™

A Self-Organized Approach For Detecting Communities In Networks, Ben Collingsworth

Theses and Dissertations

The community structure of networks reveals hidden information about the whole network structure that cannot be discerned using other topological properties. Yet, the importance of identifying community structure in networks to many fields such as medicine, social sciences and national security, calls for better approaches for performing this identification. The prevalent community detection algorithms, such as the one proposed by Girvan and Newman, utilize a centralized approach that is unlikely to scale to very large networks and does not handle dynamic networks. Further, existing algorithms provide limited information regarding community overlap, where an individual participates in multiple communities. We propose …

Regulating The Void: In‐Orbit Collisions And Space Debris, Timothy G. Nelson

Journal of Space Law

No abstract provided.

Discrete Mutations In Colorectal Cancer Correlate With Defined Microbial Communities In The Tumor Microenvironment, Michael B. Burns, Emmanuel Montassier, Juan Abrahante, Timothy K. Starr, Dan Knights, Ran Blekhman

Biology: Faculty Publications and Other Works

Variation in the gut microbiome has been linked to colorectal cancer (CRC), as well as to host genetics. However, we do not know whether genetic mutations in CRC tumors interact with the structure and composition of the microbial communities surrounding the tumors, and if so, whether changes in the microbiome can be used as a predictor for tumor mutational status. Here, we characterized the association between CRC tumor mutational landscape and its proximal microbial communities by performing whole exome sequencing and microbiome profiling in tumors and normal colorectal tissue samples from the same patient. We find a significant association between …

Exploring The Role Of Biofilms In The Transport And Establishment Of Invasive Marine Macrofoulers, Lynn Holly Sweat

Theses and Dissertations

Biofilms dominated by bacteria and diatoms universally colonize submerged surfaces and mediate larval recruitment in benthic marine systems. The ability for macrofoulers to be transported by vessels and become globally established is likely affected by cues from the biofilm organisms they encounter. This study investigates how macrofoulers respond to biofilms shaped by local geography, transport processes and relocation. Biofilm assemblages in neighboring ports were largely unique to the site at which they were developed. Bacteria were primary drivers of variations among sites, and overall bacterial richness was an order of magnitude higher than has been reported for other marine environments. …

Depressive Symptoms As A Longitudinal Predictor Of Sexual Risk Behaviors Among African American Adolescents: Findings From Project Imppacs, Jacklyn Babowitch

Dissertations - ALL

Research that clarifies individual level factors associated with sexual risk behavior among African American adolescents remains an important public health priority. The current study examined the longitudinal association of depressive symptoms to sexual risk behaviors, and determined whether the association of depressive symptoms to risky sex varies as a function of gender in a sample of African American adolescents. A secondary aim was to examine whether self-efficacy for sex refusal and condom use mediate the depression-sexual risk relationship. Data analyses focused on baseline and three-month assessments of depressive symptoms and sexual behaviors assessed for the previous three-months, including: (a) engagement …

Long-Term Biofilm Tests With Silver Contained Electrospun Polymer Mats, Bo Peng

Dissertations - ALL

It has been reported that wounds heal faster and better in a moist, enclosed environment. Wound dressings are designed to fulfill such demands. In addition, wound dressings protect wounds from subsequent physical harm and bacterial infection. Among various types of wound dressings, electrospun wound dressings are widely marketed due to desired properties. For instance, electrospun polymers are highly porous. Water and oxygen that are necessary for cells are permeable through the porous structure. Moreover, electrospun polymers have high surface area to volume ratio. This property allows polymers to absorb extra exudate from wounds efficiently. In this study, several silver-releasing electrospun …

Development Of Multicomponent Coupled-Cluster Theory And Its Application To Nanoclusters And Molecular Systems, Benjamin Harrison Ellis

Dissertations - ALL

Many theoretical and computational methods are based upon the Born-Oppenheimer approximation. This approximation greatly simplifies the search for a wave function that describes all electrons and nuclei in a chemical system. This is accomplished by assuming that the motion of nuclei and electrons are vastly different; the motion of the two particle types is decoupled. While the BO approximation is ubiquitous in computational and theoretical studies, it is not always justifiable. There are two main cases where this approximation is not valid. The first is when nuclear and electronic motion cannot be decoupled. Decoupling the motion leads to incorrect observations …

Laboratory Investigations Into The Fate Of Aromatic Pollutants In Natural Waters, Jarod Nathaniel Grossman

Dissertations - ALL

Condensed phases in the atmosphere, such as cloud droplets and aerosols, often contain both water and organic matter (OM). Reactivity can differ significantly between aqueous and organic phases. We have measured photolysis kinetics of the polycyclic aromatic hydrocarbons (PAHs) anthracene and pyrene in several organic solvents and in water, in miscible and phase-separated aqueous-organic mixtures, in the presence of halide salts (NaCl, NaBr, and NaI), and in simulated seawater. Moreover, the roles of singlet oxygen and pH were investigated on the kinetics at atmospherically-relevant wavelengths. Photolysis rate constants generally increased with increasing solvent polarity. Our results suggest that OM could …

Identification Of Key Players In Networks Using Multi-Objective Optimization And Its Applications, R Chulaka Gunasekara

Dissertations - ALL

Identification of a set of key players, is of interest in many disciplines such as sociology, politics, finance, economics, etc. Although many algorithms have been proposed to identify a set of key players, each emphasizes a single objective of interest. Consequently, the prevailing deficiency of each of these methods is that, they perform well only when we consider their objective of interest as the only characteristic that the set of key players should have. But in complicated real life applications, we need a set of key players which can perform well with respect to multiple objectives of interest.

In this …

Structure, Dynamics And Rheology Of Surfactant Micelles And Micelle-Nanoparticle Solutions: A Molecular Dynamics Study, Abhinanden Sambasivam

Dissertations - ALL

Surfactant micelles are widely used in a number of industrial, commercial and household products and processes. Understanding flow-microstructure coupling in micellar systems can benefit applications ranging from targeted drug delivery and detergency to enhanced oil recovery and hydrofracking. Amongst micellar fluids, wormlike micelles (WLMs) are extremely interesting due to their structural similarity to polymers and their ability to constantly undergo scission and recombination at equilibrium. More recently, much has been generated in studying the effect of adding colloidal particles to WLMs. Colloidal particles can not only add functionality to the fluid but also act as viscosity modifiers. Such solutions can …

“My Training Wheels Are Off:” How First Generation College Students Made Meaning Of The Influence Of Their College Access And Support Programs, Staci Weber

Dissertations - ALL

This research explored how 47 first generation college students at a private university in the Northeast used non-profit and government-funded college access and support programs to make meaning of their college-going journeys. The participants used college access programs to prepare themselves for, gain access to, and persist at a selective postsecondary institution directly after high school. This research asked what skills and knowledge do first generation college students learn through their college access and support programs? How do first generation college students use the skills and knowledge they obtained through their college access and support programs to help navigate their …

The Bg News December 01, 2016, Bowling Green State University

BG News (Student Newspaper)

The BGSU campus student newspaper. December 01, 2016. Volume 96-Issue 30.

Senior Grateful For Generous Aid At Illinois Wesleyan, University Communications

News and Events (Discontinued Series)

No abstract provided.

Plasma Processes And Polymers Third Special Issue On Plasma And Cancer, Mounir Laroussi, Annemie Bogaerts, Nazir Barekzi

Electrical & Computer Engineering Faculty Publications

(First paragraph) This issue of Plasma Processes and Polymers is the third in a series on the applications of low temperature plasma (LTP) against cancer, or “plasma oncology.” The papers in this issue are inspired from the talks given at the third International Workshop on Plasma for Cancer Treatment (IWPCT) which took place on April 11–12, 2016 in Washington, DC, USA. IWPCT is an international workshop that was created in 2014 as a venue to share cutting edge plasma oncology research. The first IWPCT was held in Washington DC, under the co-chairmanship of Prof. Mounir Laroussi (Old Dominion University) and …

Minority Middle And High School Students' Interest In Science: An Exploration Of Teachers' Perceptions, Caroline Makere

Dissertations

A high school teacher conducted a study about minority middle and high school students’ interest in science. The problem was to find out why African American and Hispanic students were showing very little interest in science. The researcher used four middle school science teachers and nine high school science teachers, all from inner city schools in a big city of the Midwest United States except for one middle school teacher from a nearby suburb. The participants answered a survey questionnaire followed with a face-to-face recorded interview. The findings of the study confirmed that students showed little interest in science due …

Investigation Of Dynamic Biological Systems Using Direct Injection And Liquid Chromatography Mass Spectrometry, Adam Clayton Swensen

Theses and Dissertations

In biological systems, small changes can have significant impacts. It is, therefore, very important to be able to identify these changes in order to understand what is occurring in the organism. In many cases, this is not an easy task. Mass spectrometry has proven to be a very useful tool in elucidating biological changes even at a very small scale. Several different mass spectrometry based techniques have been developed to discover and investigate complex biological changes. Some of these techniques, such as proteomics, have been through years of development and have advanced to the point that anyone can complete complex …

The Effects Of L-Cysteine On Alzheimer's Disease Pathology In Apoe2, Apoe3, And Apoe4 Homozygous Mice, Stephen Gerard Cieslak

Theses and Dissertations

The APOE gene is of profound importance regarding the onset of Alzheimer's disease (AD). From the small physical differences among the protein products of the isoforms of this gene arises a profound difference in their physiologies. For example, the APOE2 isoform confers resistance to AD, the APOE3 isoform confers neutral susceptibility to AD, and the APOE4 isoform confers proneness to AD. L-cysteine is an amino acid that has several anti-AD properties, among which are its ability to sequester iron and form glutathione – a powerful antioxidant – and therefore may be a promising potential dietary supplement for ameliorating AD …

Effect Of Exotic Invasive Old World Climbing Fern (Lygodium Microphyllum) On Soil Properties, Pushpa G. Soti, Krish Jayachandran

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Old World climbing fern (Lygodium microphyllum) has become one of the most serious ecological threats to the integrity of the greater Everglades ecosystem of south Florida. In this study, we analyzed the effects of Old World climbing fern on surfacesoil characteristics at invaded sites in Florida. We compared soil characteristics of six invaded and adjacent uninvaded plots at three different locations. Our results show that the fern can grow and thrive in a wide range of soil types and the impact on the soil was site specific with effects being more prominent in sites with low nutrient status. Additionally, there …

Managing The Spread Of Alfalfa Stem Nematodes (Ditylenchus Dipsaci): The Relationship Between Crop Rotation Periods And Pest Re-Emergence, S. Jordan, Claudia Nischwitz, R. Ramirez, Luis F. Gordillo

Mathematics and Statistics Faculty Publications

Alfalfa is a critical cash/rotation crop in the western region of the United States, where it is common to find crops affected by the alfalfa stem nematode (Ditylenchus dipsaci). Understanding the spread dynamics associated with this pest would allow growers to design better management programs and farming practices. This understanding is of particular importance given that there are no nematicides available against alfalfa stem nematodes and control strategies largely rely on crop rotation to non-host crops or by planting resistant varieties of alfalfa. In this paper we present a basic host-parasite model that describes the spread of the …

A Pes Study Of Factors Influencing Metal Partitioning In Aquatic Systems: “Design Of Experiment As, Cd, Co, Cr, Cu, Pb, Ni, And Zn”, Eid A. Alkhatib, John Rapaglia, Leon Theim

Chemistry & Physics Faculty Publications

Mobility and bioavailability of heavy metals are related to their partitioning amongst suspended sediment and water. A Particle Entrainment Simulator (PES) is used to simulate sediment resuspention in natural surface water systems. The simulations were carried out under various conditions of water/suspended solids conditions. Five factors, each at various levels, are tested collectively: the pH of water at two levels (4 and 8), shear stress on bottom sediment at three levels (0.1, 0.3, and 0.5 N/m2 ) salinity of water at two levels (0.01 and 14.0 ppt), organic matter in sediment at three levels (0.50, 1.93, and 3.80%) and temperature …

Spatial Distribution Of Antibiotic Resistance In Soils Receiving Beef Feedlot Runoff, Scott Speicher

Department of Environmental Engineering: Theses and Other Student Research

A study was conducted to provide new insight on the potential contribution to antibiotic resistance from the land application of beef feedlot runoff to soil. This study reports the distribution and quantity of antibiotic resistant bacteria (ARBs), fecal indicator bacteria (FIB), and antibiotic resistance genes (ARGs) in soil from (i) a field receiving long-term application of beef feedlot runoff holding pond effluent and (ii) a cool-season pasture with no history of supplemental manure application.

Soil samples were collected June 2015 at the U.S. Meat Animal Research Center near Clay Center, Nebraska. A response surface sampling design (RSSD) model based on …

Optimal Grading For Strength And Functionality Of Parts Made Of Interpenetrating Polymer Networks: Load Capacity Enhancement, Zhong Chen

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Uniform parts with stress concentrations or singularities are prone to failure under relatively small loads, which motivates researchers to seek methods to enhance the strength of these parts. This dissertation studies the optimization of material grading to design parts made of functionally graded interpenetrating polymer networks (FG-IPNs) to improve their load capacity.

An acrylate/epoxy IPN with variations of elastic Young’s modulus, Poisson’s ratio, and ultimate stress at failure is used for optimization of a plate with stress concentration. The grading is optimized by attaching the finite element method (FEM) solver to a general purpose bound-constrained optimizer. Two examples, a plate …

Illuminating Hopewell Legacy Data: A Case Study Of Mound 23 At Hopewell Mound Group, Margaret Robinson

Department of Anthropology: Theses and Student Research

Digital archives present new opportunities for transparency, context and accessibility by digitizing and publishing limitedly accessible collections of archival documents and artifacts. Due to the destructive nature of archaeological inquiry these datasets are the only remaining materials from which archaeologists can make interpretations about past human behavior. The objective of this thesis was to be a case study for the usability of legacy data from Hopewell Mound Group by examining newly accessible data sources through the Ohio Hopewell digital archive (hopewell.unl.edu). The resulting databases for the burial data and artifacts of Hopewell Mound Group’s Mound 23 are a combination of …

Initiating Race: Fraternal Organizations, Racial Identity, And Public Discourse In American Culture, 1865-1917, John D. Treat

Graduate Theses and Dissertations

Drawing on ritual books, organizational records, newspaper accounts, and the data available from cemetery headstones and census records, this work argues that adult fraternal organizations were key to the formation of civic discourse in the United States from the years following the Civil War to World War I. It particularly analyzes the role of working-class white and African-American organizations in framing racial identity, arguing that white organizations gave up older, comprehensive ideas of citizenship for understandings of Americanism rooted in racism and nativism. Counterbalancing this development, now-forgotten African-American fraternal organizations were among the earliest advocates of Afrocentrism. These organizations, form …

Effect Of Delayed Wrapping And Wrapping Source On Intake And Digestibility Of Alfalfa Silage In Gestating Sheep, Valens Niyigena

Graduate Theses and Dissertations

Baling silage with oxygen can result in dry matter deterioration and reduce silage intake by animals. This study was conducted to investigate the effects of two different wrapping sources and time intervals between baling and wrapping on intake and digestibility of alfalfa silage. The second objective was to assess the correlation of alfalfa silage fermentation parameters with intake and digestibility parameters in gestating sheep. Alfalfa silage was baled in large round bales then wrapped with plastic either with (KURA) or without (SUN) an oxygen-limiting barrier either the day of baling or 1, 2 or 3 d after baling. Beginning in …

Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown

Graduate Theses and Dissertations

AIM: Sarocpenic obesity is a national concern within the United States because this metabolic syndrome is tied with reduced mobility and quality of life. Both obesity and aging are associated with insulin-resistance, chronic low-grade inflammation and muscle weakness. Skeletal muscle regeneration is a process that involves the coordinated effort of myogenic regulatory factors (MRFs), inflammatory signaling, and extracellular matrix (ECM) remodeling for optimal regeneration. It has been demonstrated that obesity and aging have a reduction in muscle regeneration. It has not been examined if sarcopenic obesity will further reduce muscle mass and the regenerative process. The purpose of this study …

Effects Of Acute Heat And Oxidative Stress On The Hepatic Expression Of Orexin And Its Related Receptors, Stephanie Khaldi

Graduate Theses and Dissertations

It is widely known that orexin A and B peptides as well as their receptors are expressed in the hypothalamus and distributed throughout the central nervous system, but there have been few studies regarding its presences in other parts of the body. There is now evidence that orexin (ORX) and its receptors (ORXR1/2) are present in the avian liver; however, their regulation under different environmental conditions is still unknown. In the current study, we sought to determine the effects of heat and oxidative stress using hydrogen peroxide (H2O2) and 4-hydroxynonenal (4-HNE) on the hepatic expression of ORX and ORXR1/2 in …

Theory And Practice Of The Proposed Conceptual Framework: Evidence From The Field, Kevin Ow Yong, Chu Yeong Lim, Pearl Hock-Neo Tan

Research Collection School Of Accountancy

We provide survey evidence of chartered accountants' perspectives on the proposed conceptual framework of the International Accounting Standards Board. Our survey obtains their views on the changes in the definitions of assets and liabilities, recognition criterion, and additional guidance in these areas, as well as issues relating to other comprehensive income, business model-based accounting, and choice of measurement basis. Our field evidence suggests broad consensus with respect to most of these changes. The areas that generate the most disagreement among our respondents relate to the removal of economic benefits in the proposed asset definition, the proposal to remove the minimum …

Examining Denitrification In Agricultural Ditch Sediments Vegetated With Rice Cutgrass (Leersia Oryzoides): Modeling Seasonal Variation Across Increasing Levels Of Nitrate Loading And Model Application To Pre-Existing Datasets, Shannon Lee Speir

Graduate Theses and Dissertations

Nitrogen (N) derived from fertilizer application in agricultural systems may contribute to significant environmental impacts, including eutrophication of fresh and coastal waters. Rice cutgrass (Leersia oryzoides) can significantly enhance denitrification potential in agricultural ditch sediments, but relationships with known drivers are not well understood. To address this, I examined effects of nitrate (NO3-) availability on dinitrogen gas (N2) and NO3- fluxes seasonally in Chapter 2. Denitrification rates were measured as N2 flux from intact vegetated sediment cores using Membrane Inlet Mass Spectrometry (MIMS). Michaelis-Menten models were developed from observations to mathematically describe N2 fluxes across the spring, summer, and fall …

Selection Of Drought-Tolerant Soybean Lines Using A Field Screening Method And Identification Of Qtls For Slow Wilting And Nitrogen Fixation Associated With Drought-Tolerance, Mirta Beatriz Dalzotto

Graduate Theses and Dissertations

Drought causes significant yield reductions in soybean. The development of drought-tolerant cultivars is an effective alternative to overcome this abiotic stress. Slow wilting, prolonged nitrogen fixation, and minimal yield reduction under water stress play an important role in evaluating breeding materials. Despite advances in knowledge about plant responses to drought conditions, there is little information on effective methodologies for phenotype screening in the field, and some QTLs have been identified for drought tolerance. Field screenings under drought and irrigated conditions are necessary to detect drought tolerant lines. In addition, QTLs and molecular makers associated with drought tolerance traits will greatly …