Digital Commons Network^™

Drinking Motives Underlying Internalizing And Externalizing Pathways To Alcohol Misuse In College Students, Jeanne Savage

Theses and Dissertations

Alcohol misuse, including heavy episodic use and negative consequences, is a major public health concern and a particular problem among college students. The etiology of alcohol misuse is not well resolved, with multiple and often contradictory factors implicated in its development. Genetic factors influence alcohol misuse but few specific genes have been identified. A potential reason for these challenges is that alcohol misuse is phenotypically and genetically heterogeneous; that is, there are multiple causal pathways underlying its development. Previous typologies have suggested that distinct internalizing and externalizing pathways are involved, with corresponding differences in profiles of personality, temperament, and comorbid …

Accurate Acoustic Ranging System Using Android Smartphones, Mohammadbagher Fotouhi

Theses and Dissertations

ACCURATE ACOUSTIC RANGING SYSTEM USING ANDROID SMARTPHONES

By Mohammadbagher Fotouhi, Master of Science

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University

Virginia Commonwealth University 2017

Major Director: Dr. Ruixin Niu, Associate Professor of Department of Electrical and Computer Engineering

In this thesis, we present the design, implementation, and evaluation of an android ranging system, a high-accuracy acoustic-based ranging system which allows two android mobile phones to learn their physical distance from each other.

In this system we propose a practical solution for accurate ranging based on acoustic communication …

Cooperative Wideband Spectrum Sensing Based On Joint Sparsity, Ghazaleh Jowkar

Theses and Dissertations

COOPERATIVE WIDEBAND SPECTRUM SENSING BASED ON JOINT SPARSITY

By Ghazaleh Jowkar, Master of Science

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University

Virginia Commonwealth University 2017

Major Director: Dr. Ruixin Niu, Associate Professor of Department of Electrical and Computer Engineering

In this thesis, the problem of wideband spectrum sensing in cognitive radio (CR) networks using sub-Nyquist sampling and sparse signal processing techniques is investigated. To mitigate multi-path fading, it is assumed that a group of spatially dispersed SUs collaborate for wideband spectrum sensing, to determine whether or not …

Development Of General Purpose Liquid Chromatography Simulator For The Exploration Of Novel Liquid Chromatographic Strategies, Lena N. Jeong

Theses and Dissertations

The method development process in liquid chromatography (LC) involves optimization of a variety of method parameters including stationary phase chemistry, column temperature, initial and final mobile phase compositions, and gradient time when gradient mobile phases are used. Here, a general simulation program to predict the results (i.e., retention time, peak width and peak shape) of LC separations, with the ability to study various complex chromatographic conditions is described. The simulation program is based on the Craig distribution model where the column is divided into discrete distance (Δz) and time (Δt) segments in a grid and is …

Validation Study Of The Science Literacy Assessment: A Measure To Assess Middle School Students' Attitudes Toward Science And Ability To Think Scientifically, Tammy Mckeown

Theses and Dissertations

This study investigated validity evidence for the Science Literacy Assessment, an instrument designed to assess middle school students’ ability to think scientifically as well as their motivation and beliefs about science (Fives, Huebner, Birnbaum, & Nicolich, 2014). Specifically, three sources of evidence were considered; internal structure, concurrent criterion-related, and predictive criterion-related. Exploratory factor analysis was utilized to examine the underlying factor structure of each of the instrument’s two components, motivation and beliefs related to science and demonstrated scientific literacy. Pearson product-moment correlations were calculated to determine the relationship between scores on the motivation and belief component of the Science Literacy …

Public Perceptions And Practices Of Solid Waste Recycling In The City Of Laramie In Wyoming, U.S.A., Upendra B. Bom, Shashidhar Belbase, Reni Bibriven Lila

All Works

© 2017 by the authors. Licensee MDPI, Basel, Switzerland. Managing household solid waste is a growing challenge for many cities. To tackle this problem, cities are turning to recycling, which is an effective tool for solid waste management. This research seeks to understand the public perceptions and practices of recycling in the City of Laramie, Wyoming. Recycling in Laramie began in 1983 with the establishment of the Ark Recycling Center. Laramie officially started its curbside recycling services in September 2011, and in April 2012 the city declared its long-term goal to achieve a 40% diversion rate by 2030. The study …

Pattern Matching Of Signature-Based Ids Using Myers Algorithm Under Mapreduce Framework, Monther Aldwairi, Ansam M. Abu-Dalo, Moath Jarrah

All Works

© The Author(s). 2017. The rapid increase in wired Internet speed and the constant growth in the number of attacks make network protection a challenge. Intrusion detection systems (IDSs) play a crucial role in discovering suspicious activities and also in preventing their harmful impact. Existing signature-based IDSs have significant overheads in terms of execution time and memory usage mainly due to the pattern matching operation. Therefore, there is a need to design an efficient system to reduce overhead. This research intends to accelerate the pattern matching operation through parallelizing a matching algorithm on a multi-core CPU. In this paper, we …

Perfectionism In Occupational Science Students: Occupational Therapy Implications, Mary Elizabeth Wagner, Renee Causey-Upton

EKU Faculty and Staff Scholarship

Purpose

The purpose of this study is to categorize perfectionism and determine how perfectionism impacts the occupations and perceived health of students in a Bachelor of Science in Occupational Science program.

Design/methodology/approach

A descriptive study with a survey component was conducted. Participants were categorized as perfectionists or non-perfectionists using the Almost Perfect Scale-Revised (APS-R). Time logs were collected to compare categories of time-use between groups over a one-week period. An online survey was conducted with a sub-sample of the perfectionists.

Findings

More students were categorized as perfectionists (N = 41) than non-perfectionists (N = 3). Both groups spent …

Flipped Learning In Synchronously-Delivered, Geographically-Dispersed General Chemistry Classrooms, Michael A. Christiansen, Louis Nadelson, Lianna K. Etchberger, Marilyn M. Cuch, Trish A. Kingsford, Leslie O. Woodward

Chemistry and Biochemistry Faculty Publications

In synchronously-delivered, multi-site classrooms, the physical separation between distance students and instructors may create a perceived divide that negatively affects learning. Building on prior experience in flipping organic chemistry in single-site face-to-face (F2F) classes, we decided to extend our approach to multi-site, synchronously-delivered general chemistry courses. Our thought was to narrow the perceived instructor-student divide in distance teaching by using the flexible in-class time that flipping affords to increase the number of positive teacher/distance-student interactions. In this effort, we gradually developed a technique called “bridging questions,” through which the instructor becomes more familiar with student interests and then connects those …

St. Louis Area Earthquake Hazards Mapping Project: Seismic And Liquefaction Hazard Maps, Chris H. Cramer, Robert A. Bauer, Jaewon Chung, J. David Rogers, Larry Pierce, Vicki Voigt, Brad Mitchell, David Gaunt, Robert A. Williams, David J. Hoffman, Gregory L. Hempen, Phyllis J. Steckel, Oliver Salz Boyd, Connor M. Watkins, Kathleen B. Tucker, Natasha S. Mccallister

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We present probabilistic and deterministic seismic and liquefaction hazard maps for the densely populated St. Louis metropolitan area that account for the expected effects of surficial geology on earthquake ground shaking. Hazard calculations were based on a map grid of 0.005°, or about every 500 m, and are thus higher in resolution than any earlier studies. To estimate ground motions at the surface of the model (e.g., site amplification), we used a new detailed near-surface shear-wave velocity model in a 1D equivalent- linear response analysis. When compared with the 2014 U.S. Geological Survey (USGS) National Seismic Hazard Model, which uses …

Natural Recession Of The Eastern Margin Of The Leofnard Salt In Western Canada, Neil Lennart Anderson, Robert James Sidford Brown, Dale A. Cederwall

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Lloydminster area (T35-65, R15W3M-10W4M) of east-central Alberta and west-central Saskatchewan, Canada, is dissected by the north-northwest trending updip active dissolution margin, of the Devonian Leofnard Member rock salt. West of this margin, up to 150 m of rock salt is preserved; updip and to the east, the salt has mostly been leached from the rock record. The margin is up to 40 km wide and characterized by extreme local variations in net salt thickness. The dissolution of the Leofnard rock salt in the Lloydminster area has resulted in the entrapment of significant hydrocarbon accumulation. Stratigraphic traps, for example, have …

Perceptions Of Contributions Of Business Coaches To Female Entrepreneurial Success, Tracy I. Timberlake

Theses and Dissertations

Although coaching has seen tremendous growth and success, it is still regarded as controversial because there is no governing body that oversees coaches or the coaching industry. In this manner, the industry has not achieved uniformity, therefore is under much scrutiny with regards to the validity of the industry as a whole. With female entrepreneurship on the rise, many industry personnel are hiring business coaches to teach them the business building skills they need to start their solo ventures. This study aimed to understand the perceptions of the one-on-one business coaching experience from the perspective of the client. Because there …

Analysis Of Ior Pilots In Bakken Formation By Using Numerical Simulation, Dheiaa Alfarge, Mingzhen Wei, Baojun Bai, Mortadha Alsaba

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Bakken is the most productive formation among unconventional plays in North America. This formation has 7.4 billion barrels of recoverable oil. However, the primary oil recovery is still low as 5-10%. Miscible natural gas and carbon dioxide (CO₂) might be the most two potential strategies to improve oil recovery in such complex play. In this study, some of the IOR pilots which have been conducted in Montana, North Dakota, and South Saskatchewan have been presented. The performance results of these pilots in US-Bakken versus Canadian-Bakken have been compared. Moreover, the reasons beyond the successful IOR pilots in Canadian-Bakken …

The Effects Of Disturbance And Species Specific Interactions On Diversity In An Agent Based Forest Simulation, Matthew E. Mills

Theses and Dissertations

In ecology literature, there is much data which suggests that conspecific negative density dependence (CNDD) and abiotic disturbances increase biodiversity in forests. This thesis elucidates the notion that not only do these two forces increase diversity, but they may also interact with one another in order to achieve higher levels of biodiversity. Abiotic disturbances, like fires and hurricanes, can indirectly impact conspecific effects because when these forces remove individuals from the landscape, the role of the conspecific effects will change. The interaction of these two factors in biodiversity are explored in an agent based forest simulation through a resource surface. …

Investigating The Relationship Between Emotional Intelligence And Cultural Intelligence To Attitudes Towards Team-Based Learning In Undergraduate Pre-Health Profession Students, Kevin A. Harris

Theses and Dissertations

Improving patient outcomes has long been the rationale supporting calls to reform health care delivery systems and health profession education programs (Greiner, 2002; Institutes of Medicine, 2001, 2004; O’Neil & Pew Health Professions Commission, 1998). In 2003, the Institute of Medicine shared its vision statement for health professions education, asserting that “[a]ll health professionals should be educated to deliver patient-centered care as members of an interdisciplinary team, emphasizing evidence-based practice, quality improvement approaches and informatics” (Knebel & Greiner, 2003, p. 3).

Despite the importance placed on teamwork in health sciences education, little attention has been devoted to understanding underlying factors …

Comparing The Structural Components Variance Estimator And U-Statistics Variance Estimator When Assessing The Difference Between Correlated Aucs With Finite Samples, Anna L. Bosse

Theses and Dissertations

Introduction: The structural components variance estimator proposed by DeLong et al. (1988) is a popular approach used when comparing two correlated AUCs. However, this variance estimator is biased and could be problematic with small sample sizes.

Methods: A U-statistics based variance estimator approach is presented and compared with the structural components variance estimator through a large-scale simulation study under different finite-sample size configurations.

Results: The U-statistics variance estimator was unbiased for the true variance of the difference between correlated AUCs regardless of the sample size and had lower RMSE than the structural components variance estimator, providing better type 1 error …

Upper Elementary Reading Instruction In The Age Of Accountability: Balancing Best Practices With Pressures To Achieve On High-Stakes Tests, Christina H. Saunders

Theses and Dissertations

The present study identifies reading instructional practices used in upper elementary classrooms during the age of high-stakes test accountability and compares reading practices among schools of varying accreditation status and socio-economic status (SES). The current study partially replicates and extends a study conducted by Baumann, Hoffman, Duffy-Hester, and Ro in 2000. The Baumann et al. (2000) study provides a frame of reference to compare instructional practices prior to high stakes testing with those used in the current high stakes testing environment. Third- through fifth-grade teachers in seven school districts in central Virginia were asked to complete an electronic survey. Descriptive …

Weighted Quantile Sum Regression For Analyzing Correlated Predictors Acting Through A Mediation Pathway On A Biological Outcome, Bhanu M. Evani

Theses and Dissertations

Abstract

Weighted Quantile Sum Regression for Analyzing Correlated Predictors Acting Through a Mediation Pathway on a Biological Outcome

By

Bhanu M. Evani, Ph.D.

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University.

Virginia Commonwealth University, 2017.

Major Director: Robert A. Perera, Asst. Professor, Department of Biostatistics

This work examines mediated effects of a set of correlated predictors using the recently developed Weighted Quantile Sum (WQS) regression method. Traditionally, mediation analysis has been conducted using the multiple regression method, first proposed by Baron and Kenny (1986), which has since …

Efficient Integration Of Plasmonic And Excitonic Properties Of Metal And Semiconductor Nanostructures Via Sol-Gel Assembly, Dilhara Liyanage

Theses and Dissertations

Research in nanoscience has gained noteworthy interest over the past three decades. As novel chemical and physical properties that are vastly different from extended solids are realized in nanosized materials, nanotechnology has become the center of attention for material in research community. Much to our amazement, investigations in the past two decades revealed that the nanocrystalline semiconductors are “THE PRIME CANDIDATES” to meet the growing energy demand, sensor development, cellular imaging and a number of other optoelectronic applications. Nonetheless, synthesis of nanostructures with control over physical parameters is not sufficient, yet assembling them into functional nanoarchitectures with unique and tunable …

Low-Temperature Fabrication Process For Integrated High-Aspect Ratio Metal Oxide Nanostructure Semiconductor Gas Sensors, William Paul Clavijo

Theses and Dissertations

This work presents a new low-temperature fabrication process of metal oxide nanostructures that allows high-aspect ratio zinc oxide (ZnO) and titanium dioxide (TiO₂) nanowires and nanotubes to be readily integrated with microelectronic devices for sensor applications. This process relies on a new method of forming a close-packed array of self-assembled high-aspect-ratio nanopores in an anodized aluminum oxide (AAO) template in a thin (2.5 µm) aluminum film deposited on a silicon and lithium niobate substrate (LiNbO₃). This technique is in sharp contrast to traditional free-standing thick film methods and the use of an integrated thin aluminum film …

Sol-Gel Chemistry: An Advanced Technique To Produce Macroscopic Nanostructures Of Metal And Semiconductor Colloids, Lamia Nahar

Theses and Dissertations

The fascinating physical properties that arise in materials limited to dimensions of 1-100 nm have gained noteworthy interest from the scientific community. Accordingly, there has been a lot of attention paid to the synthesis of discrete nanoparticles (NPs) and they are being investigated for a range of advanced technologies. Nonetheless, efficient use of nanomaterials in device applications require them to be assembled into solid state macro-structures while retaining their unique, nanoparticulate properties. To date, most commonly investigated assembling techniques include: covalent coupling of NPs surface groups, control evaporation of the solvent to produce ordered supercrystals or non-ordered glassy films, and …

A Multi-Method Exploration Of The Genetic And Environmental Risks Contributing To Tobacco Use Behaviors In Young Adulthood, Elizabeth K. Do

Theses and Dissertations

Tobacco use remains the leading preventable cause of morbidity and mortality in both the United States and worldwide. Twin and family studies have demonstrated that both genetic and environmental factors are important contributors to tobacco use behaviors. Understanding how genes, the environment, and their interactions is critical to the development of public health interventions that focus on the reduction of tobacco related morbidity and mortality. However, few studies have examined the transition from adolescent to young adulthood – the time when many individuals are experimenting with and developing patterns of tobacco use. This dissertation thesis seeks to provide a comprehensive …

Gravitational Microlensing, Wesley M. Barnes

Theses and Dissertations

A gravitational microlensing event occurs when a foreground star passes near our line of site to a background source star. The foreground star acts as a lens, perturbing the image of the source star and amplifying the apparent intensity. Because the lens is in motion relative to the source star, the amplification is a function in time, resulting in a characteristic microlensing light curve. If the lens happens to have a planetary companion, the resulting light curve will be perturbed due the planet and the characteristics of the binary system can be ascertained.

Synthetic Modeling Of Power Grids Based On Statistical Analysis, Seyyed Hamid Elyas 8045266

Theses and Dissertations

The development of new concepts and methods for improving the efficiency of power networks needs performance evaluation with realistic grid topology. However, much of the realistic grid data needed by researchers cannot be shared publicly due to the security and privacy challenges. With this in mind, power researchers studied statistical properties of power grids and introduced synthetic power grid topology as appropriate methodology to provide enough realistic power grid case studies. If the synthetic networks are truly representative and if the concepts or methods test well in this environment they would test well on any instance of such a network …

The Generalized Monotone Incremental Forward Stagewise Method For Modeling Longitudinal, Clustered, And Overdispersed Count Data: Application Predicting Nuclear Bud And Micronuclei Frequencies, Rebecca Lehman

Theses and Dissertations

With the influx of high-dimensional data there is an immediate need for statistical methods that are able to handle situations when the number of predictors greatly exceeds the number of samples. One such area of growth is in examining how environmental exposures to toxins impact the body long term. The cytokinesis-block micronucleus assay can measure the genotoxic effect of exposure as a count outcome. To investigate potential biomarkers, high-throughput assays that assess gene expression and methylation have been developed. It is of interest to identify biomarkers or molecular features that are associated with elevated micronuclei (MN) or nuclear bud (Nbud) …

The Undergraduate 2017, Saint Mary's College Of California

The Undergraduate Spectrum

No abstract provided.

A Hybrid Nonlinear Vibration Energy Harvester, Wei Yang, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

Vibration energy harvesting converts mechanical energy from ambient sources to electricity to power remote sensors. Compared to linear resonators that have poor performance away from their natural frequency, nonlinear vibration energy harvesters perform better because they use vibration energy over a broader spectrum. We present a hybrid nonlinear energy harvester that combines bi-stability with internal resonance to increase the frequency bandwidth. A two-fold increase in the frequency bandwidth can be obtained compared to a bi-stable system with fixed magnets. The harvester consists of a piezoelectric cantilever beam carrying a movable magnet facing a fixed magnet. A spring allows the magnet …

The Transcriptome Response Of The White-Rot Fungus Phanerochaete Chrysosporium To Maple And Miscanthus, Mashael Rashed Alaradi

Masters Theses

Lignocellulosic biomass is a valuable feedstock for the production of liquid biofuels. However, liquid biofuel production from lignocellulose is economically challenging due to the difficulties associated with separating the cellulosic sugars from lignin. In addition, the current thermochemical methods to deconstruct lignocellulose typically involve hazardous chemicals that can negatively impact the environment. Recent studies have demonstrated the efficacy of white-rot fungi as alternative pretreatment agents that can lower the costs of lignocellulose deconstruction and reduce negative impacts on the environment. However, understanding of the biochemical mechanisms of lignocellulose breakdown used by these fungi is limited, particularly with respect to the …

Behavior Of Different Sizes Of Strontium Titanate Substrates In Electrochemical Modifications, Shuxin Luo

Masters Theses

In our previous atomic force microscopy (AFM) studies of 5 mm x 5 mm single crystal SrTiO₃ (STO(100)) substrates, rutile TiO₂ crystals were found on the substrates surfaces after electrochemical modification. These crystals were found mainly in the area of contact between the substrate and the gold-coated alligator clip that was not supposed to be immersed into the electrolyte and that served as a connection between the STO working electrode and the potentiostat circuit. The size and density of the crystals were found to depend on electrochemical potential, its polarity, the length of modifying time, and the total …

Functionalized Bodipy Dyes For Near-Infrared Emission Of Lanthanide Complexes, Rukshani Wickrama Arachchi

Masters Theses

For many decades, fluorophores have been used to investigate natural systems, but autofluorescence and photobleaching diminish the detection capacity. Recently, BODIPY based lanthanide complexes have been synthesized and their photophysical properties have been investigated. These complexes exhibit higher emission efficiencies at NIR region with longer NIR lifetimes upon exciting at longer wavelength.

In this study, two BODIPY based lanthanide complexes were synthesized and their photophysical properties were evaluated. BODIPY based ligands were synthesized with phenanthroline as the ligand binding group. These ligands exhibit strong absorption at 527 nm and 532 nm, fluorescence at 540 nm and 548 nm with 0.55 …