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Impacts Of Physical Transport On Estuarine Phytoplankton Dynamics And Harmful Algal Blooms, Qubin Qin Jan 2019

Impacts Of Physical Transport On Estuarine Phytoplankton Dynamics And Harmful Algal Blooms, Qubin Qin

Dissertations, Theses, and Masters Projects

The spatial and temporal variability of phytoplankton biomass in estuaries is determined by both local processes and transport processes. Local processes include biological processes (e.g., photosynthesis, respiration/excretion, and grazing) and settling, whereas transport processes include advective and diffusive transports. Transport processes have been demonstrated to regulate phytoplankton dynamics significantly by distributing both phytoplankton and other dissolved and particulate substances (e.g., nutrients, salts, sediments, and chromophoric dissolved organic matter). Yet, these transport properties lack a framework that unifies the pieced description of their various effects, and quantification of their importance under various environmental conditions. This dissertation highlights the role of horizontal …


An Action Research Study: Inclusive Culture Formation In A New High School, David Wayne Parrish Jan 2019

An Action Research Study: Inclusive Culture Formation In A New High School, David Wayne Parrish

Dissertations, Theses, and Masters Projects

The culture of a school community is critical to every aspect of its existence, including academic expectations, degree of inclusiveness, safety, and overall well-being of students and staff. While culture can be an abstract, elusive concept, it makes itself known upon entering the school. School culture can exist on multiple levels, exerting a cohesive impact on relationships and interactions and opportunities. Adding to its complexity, a school culture can be perceived differently by individuals, depending on their unique experiences. Further, a school culture is inevitable and difficult to change; a culture will form and once formed, is resistant to even …


When A Man Loves A Woman: The Lived Experiences Of Male Sober Partners In Romantic Relationships With Women Who Struggle With Addiction, Katharine Rose Sperandio Jan 2019

When A Man Loves A Woman: The Lived Experiences Of Male Sober Partners In Romantic Relationships With Women Who Struggle With Addiction, Katharine Rose Sperandio

Dissertations, Theses, and Masters Projects

The purpose of the phenomenological study was to explore the experiences of male sober partners who are in romantic relationships with women who struggle with addiction. The theoretical framework of the study was social constructivism given the impact of social gender roles on experiences. Five male sober partners were identified as meeting the criteria for the study. Data collection consisted of a semi-structured interview. The interview entailed demographic and open-ended questions that highlighted the participants’ experiences. The primary questions of the study were: What does it mean to be a sober male who is in a relationship with a woman …


Student Interactions, Connectedness, And Retention In An Online Mba Program: An Exploratory Study, Karen G. Conner Jan 2019

Student Interactions, Connectedness, And Retention In An Online Mba Program: An Exploratory Study, Karen G. Conner

Dissertations, Theses, and Masters Projects

The market for online education is competitive, especially for graduate programs such as the Master of Business Administration (MBA). Attrition rates vary widely, and educators must understand the needs of online students and create engaging quality programs to be competitive. Social interaction and student connectedness are particularly important in online MBA programs where one of the expected benefits is the opportunity for students to build strong professional networks. This mixed methods study explores the student interactions, connectedness, and retention in the Online MBA Program at William & Mary. While previous research has explored building community in an online educational environment, …


On Enhancing Security Of Password-Based Authentication, Yue Li Jan 2019

On Enhancing Security Of Password-Based Authentication, Yue Li

Dissertations, Theses, and Masters Projects

Password has been the dominant authentication scheme for more than 30 years, and it will not be easily replaced in the foreseeable future. However, password authentication has long been plagued by the dilemma between security and usability, mainly due to human memory limitations. For example, a user often chooses an easy-to-guess (weak) password since it is easier to remember. The ever increasing number of online accounts per user even exacerbates this problem. In this dissertation, we present four research projects that focus on the security of password authentication and its ecosystem. First, we observe that personal information plays a very …


Additive Manufacturing Of Nanomaterial Based Hierarchical Structures, John Michael Gardner Jan 2019

Additive Manufacturing Of Nanomaterial Based Hierarchical Structures, John Michael Gardner

Dissertations, Theses, and Masters Projects

Aerospace systems demand high performance materials that minimize weight while functioning under extreme environmental conditions. One way to meet these requirements is by incorporating hierarchical structures into part design. These structures are known to impart unique mechanical properties not characteristic of the bulk material such as high strength and toughness. It is difficult, however, to manufacture these structures due to the inherent trade-off between part size and feature resolution in traditional manufacturing processes. Additive manufacturing offers a potential solution to these issues by allowing material placement directly at desired locations. This loosens geometric constraints and allows for multiple contiguous materials …


A Phenomenological Study Of Student Engagement In An Urban K-8 School, David Joseph Gesualdi Jan 2019

A Phenomenological Study Of Student Engagement In An Urban K-8 School, David Joseph Gesualdi

Dissertations, Theses, and Masters Projects

Student engagement is an indicator of student achievement. For students living in poverty it is difficult to engage in a school that is not relatable to their own cultural norms and values. This phenomenological study sought to understand the lived experiences of these students and their teachers related to student engagement. The purpose of this study was to provide insights and perspectives of students’ and teachers’ personal experiences within a mathematics classroom. The key research questions targeted understanding student perceptions of their own level of engagement—behaviorally, emotionally, and cognitively; teacher perceptions of their students’ levels of engagement; instructional factors that …


Giant Steps: Toward A Developmental Trajectory Of Creative Talent As A Jazz Improviser, Anthony Michael Washington Jan 2019

Giant Steps: Toward A Developmental Trajectory Of Creative Talent As A Jazz Improviser, Anthony Michael Washington

Dissertations, Theses, and Masters Projects

Expert jazz improvisers follow a developmental trajectory that is useful to understanding creative ability. Because this domain uses creativity as a fundamental part of its performance, its development naturally includes techniques for developing one’s creativity. This study explored the development of expert and eminent jazz improvisers' creative abilities and delineated critical experiences, skills, dispositions, and activities associated with developing elite talent in this domain. I conducted interviews with expert jazz improvisers to gain retrospective accounts of their talent development process in addition to exploring autobiographical and biographical accounts of developmental activities of selected eminent jazz improvisers. I employed grounded theory …


An Evaluation Of An Online High School Summer Credit Recovery Program To Maintain Virginia On-Time Graduation, Melissa Luanne Bentley Jan 2019

An Evaluation Of An Online High School Summer Credit Recovery Program To Maintain Virginia On-Time Graduation, Melissa Luanne Bentley

Dissertations, Theses, and Masters Projects

In an attempt to maintain on-time graduation rates and reduce dropout rates, school districts, such as the one in this study, implement credit recovery programs. In an effort to improve student graduation rates and address graduation disparities, the Virginia school district in this study implements a summer credit recovery program that utilizes accelerated online learning as opposed to traditional direct instruction. This study sought to evaluate the effectiveness of the summer program as it relates to the success of student credit recovery and verified credit achievement to determine if there is a correlation to program participation and remaining on-track for …


Interfacial Forces Of 2d Materials At The Oil–Water Interface, William Winsor Dickinson Jan 2019

Interfacial Forces Of 2d Materials At The Oil–Water Interface, William Winsor Dickinson

Dissertations, Theses, and Masters Projects

Two-dimensional (2D) materials, including graphene and graphene oxide (GO), are a subject of interest for many researchers due to their exceptional properties (strength, conductivity, etc.). These materials, comprised of atomically-thin sheets, may naturally occur stacked together like sheets of paper, but their most interesting properties emerge when separated into individual layers. However, scaling up the processes used to isolate single sheets of some of these materials, particularly graphene, has proven problematic. They can be fiercely resistant to exfoliation, difficult to disperse, and have a worrying propensity to restack. All these problems contribute to the great difficulty these fascinating materials have …


"It's Not Meant For Us": Exploring The Intersection Of Gentrification, Public Education, And Black Identity In Washington, D.C., Shea Winsett Jan 2019

"It's Not Meant For Us": Exploring The Intersection Of Gentrification, Public Education, And Black Identity In Washington, D.C., Shea Winsett

Dissertations, Theses, and Masters Projects

This dissertation discusses themes of racial identity, meaning of space, and class through an exploration of the intersection of gentrification and public education in Washington, D.C. Through analysis of middle-class responses to gentrification I argue, 1) that the public education system is a site of gentrification, as it has become a site of capitalistic development and Black displacement; 2) that the American concept of race, including race relations, is not an aberration of typical American society, but a defining cultural feature; and 3) the best way to understand race and class in America is to use theory constructed from the …


Age-Related Differences In Inhibitory Function: Investigation Of Simon And Flanker Conflicts In Erps, Rachel Scrivano Jan 2019

Age-Related Differences In Inhibitory Function: Investigation Of Simon And Flanker Conflicts In Erps, Rachel Scrivano

Dissertations, Theses, and Masters Projects

It is unclear whether or not older adults experience more difficulty managing cognitive conflict by inhibiting distracting stimuli and/or ignoring irrelevant information than younger adults. A common procedure used to measure inhibitory function is through the use of congruent and incongruent stimuli. Specifically, past literature that used tasks like the Simon and flanker have found differing effects on reaction times and various event-related potential (ERP) amplitudes and latencies, suggesting that either inhibitory function is a unitary mechanism or multifaceted. Moreover, research exhibits uncertainty for whether or not age influences deficits to inhibitory function. Another way to measure inhibitory deficits with …


Fluxes, Drivers, And Composition Of Carbon Exchanged At The Taskinas Creek, Va Coastal Marsh Creek-Estuarine Interface, Amanda Knobloch Jan 2019

Fluxes, Drivers, And Composition Of Carbon Exchanged At The Taskinas Creek, Va Coastal Marsh Creek-Estuarine Interface, Amanda Knobloch

Dissertations, Theses, and Masters Projects

Among the most valuable natural ecosystems, estuaries and marshes are areas of high productivity, have high economic value, and provide numerous ecosystem services. However, there is still uncertainty in marsh and estuarine carbon budgets and in our overall understanding of the drivers, composition, and fluxes of organic matter in these habitats. Part of this uncertainty is due to high spatial and temporal variability within these habitats and the range of methods used in previous studies. While the number of studies is increasing, there are still large gaps in our knowledge of marsh-estuarine interface dynamics. This study examined the concentrations, fluxes, …


A Community Of Practice For School Leaders: Its Impact On Their Perceptions Of Collaborative Practice, Levels Of Trust, Self-Awareness, And Self-Efficacy, Richard Michael Smith Jan 2019

A Community Of Practice For School Leaders: Its Impact On Their Perceptions Of Collaborative Practice, Levels Of Trust, Self-Awareness, And Self-Efficacy, Richard Michael Smith

Dissertations, Theses, and Masters Projects

“There is a marked difference between possessing knowledge and skills and being able to use them well under taxing conditions. Personal accomplishments require not only skills but self-beliefs of efficacy to use them well” (Bandura, 1993, p. 119). Low school leader self-efficacy leads to the poor performance of school leaders and declining climates in their schools (Versland, 2013). The purpose of this qualitative action research study was to examine the influence of the use of a collaborative community of practice (LCoP) on school leaders’ perceptions of their levels of trust, self-awareness, and self-efficacy. Measurement instruments included semi-structured interviews, unstructured interviews, …


The Lived Experiences Of Poor And Working-Class Students At A Wealthy University, Dane A. Pascoe Jan 2019

The Lived Experiences Of Poor And Working-Class Students At A Wealthy University, Dane A. Pascoe

Dissertations, Theses, and Masters Projects

There are several universities in the US that are highly selective and attended by students from very wealthy backgrounds. In recent years, many of these selective, wealthy universities have faced public pressure to enroll higher numbers of poor and working-class students. Not much is known, however, about the experiences of poor and working-class students who attend these universities. My research sought to shed light on this by asking, “What are the lived experiences of poor and working-class students who attend a wealthy university?” I answered this question with a hermeneutic phenomenological study of poor and working-class students who attended a …


Animal Waste And Antibiotic Impacts On Microbial Denitrification In Terrestrial And Aquatic Ecosystems, Miguel Albergaria Furtado Semedo Jan 2019

Animal Waste And Antibiotic Impacts On Microbial Denitrification In Terrestrial And Aquatic Ecosystems, Miguel Albergaria Furtado Semedo

Dissertations, Theses, and Masters Projects

The global increase in livestock and poultry production observed in the last decades has led to an increase in animal waste generated. The animal waste contains high levels of nitrogen and may carry antibiotics that can disturb important microbial activities such as denitrification in terrestrial and aquatic ecosystems. Disturbances of microbial denitrification can have detrimental consequences to environmental health. In the terrestrial environment, denitrification is an important source and sink of N2O, a potent greenhouse gas in the atmosphere. In aquatic ecosystems, denitrification is a dominant NO3- removal pathway, contributing to prevent eutrophication. The overall goal of this dissertation is …


Unexplored Aspects Of The Biotic Filter To Seedling Recruitment In Aquatic Environments, Andrew James Johnson Jan 2019

Unexplored Aspects Of The Biotic Filter To Seedling Recruitment In Aquatic Environments, Andrew James Johnson

Dissertations, Theses, and Masters Projects

Sexual reproduction provides submerged aquatic vegetation (SAV) populations unique opportunities for dispersal, genetic mixing, and resilience in the event of catastrophic population declines. Relative to asexual reproduction, sexual reproduction is a risky resource investment and can have a lower probability of success. A wide variety of abiotic and biotic interactions common in both terrestrial and aquatic environments can lead to significant mortality of seeds and seedlings. The goal of this dissertation is to explore the diversity of biological interactions that influence seed and seedling survival in SAV that drive the population dynamics and restoration success of SAV species. A combination …


Improving Wifi Sensing And Networking With Channel State Information, Yongsen Ma Jan 2019

Improving Wifi Sensing And Networking With Channel State Information, Yongsen Ma

Dissertations, Theses, and Masters Projects

In recent years, WiFi has a very rapid growth due to its high throughput, high efficiency, and low costs. Multiple-Input Multiple-Output (MIMO) and Orthogonal Frequency-Division Multiplexing (OFDM) are two key technologies for providing high throughput and efficiency for WiFi systems. MIMO-OFDM provides Channel State Information (CSI) which represents the amplitude attenuation and phase shift of each transmit-receiver antenna pair of each carrier frequency. CSI helps WiFi achieve high throughput to meet the growing demands of wireless data traffic. CSI captures how wireless signals travel through the surrounding environment, so it can also be used for wireless sensing purposes. This dissertation …


“It's Not About Us": The Erasure Of African American Heritage And The Rehistoricization Of The First Africans On Jamestown Island, Virginia, Lamarise C. Reid Jan 2019

“It's Not About Us": The Erasure Of African American Heritage And The Rehistoricization Of The First Africans On Jamestown Island, Virginia, Lamarise C. Reid

Dissertations, Theses, and Masters Projects

This thesis explores the complex relationship between making African Diaspora history and culture visible at Historic Jamestowne, a setting that has historically been seen as "white". The four hundredth anniversary of the forced arrival of Africans in Virginia has created a fraught space to examine African American collective memories of shared history, community and commemoration. This thesis operationalizes Page and Thomas's (1994) "white public space" which describes the utilization of "locations, sites, patterns, configurations or devices that routinely discursively, and sometimes coercively privilege Euro-Americans over nonwhites" (1994: 111). When this concept is applied to the construction of heritage and production …


A Program Evaluation Of Student And Teacher Perceptions Of An Online Edgenuity High School Course Program In An Urban High School, Titinesha Llewellyn Jan 2019

A Program Evaluation Of Student And Teacher Perceptions Of An Online Edgenuity High School Course Program In An Urban High School, Titinesha Llewellyn

Dissertations, Theses, and Masters Projects

Abstract This program evaluation is concerned with the value of online learning for academic student achievement as perceived by teachers and students. Online learning programs are becoming commonplace within traditional educational settings. These types of programs resolve a variety of educational issues related to equal access of curricula, funding, and quality. The current issue lies with educational institutions’ ability to implement these types of programs using research-based methods and strategies that enhance academic student achievement. This study initiates the research by identifying the perceptions of the stakeholder participants in the Edgenuity online learning program regarding graduation rates and other comparisons …


Teaching Along The Way: An Ethnographic Study Of Faculty Growth And Sensemaking On The Camino De Santiago, Benjamin Boone Jan 2019

Teaching Along The Way: An Ethnographic Study Of Faculty Growth And Sensemaking On The Camino De Santiago, Benjamin Boone

Dissertations, Theses, and Masters Projects

This study examined the experiences of faculty members from U.S. universities who led students on a short-term summer study abroad program that incorporated the Camino de Santiago, a medieval pilgrimage route in Spain. The study sought to understand how faculty leaders engaged in sensemaking (Weick, 1995) of these experiences in the context of their faculty roles on their home campuses. The ethnographic methods included six years of field work in Spain, participant observation as faculty program director, and in-depth interviews with faculty leaders. The findings show that participants engaged in sensemaking through three theoretical constructs. The construct of family addresses …


Examining Persistence: The Influence Of Joining Of Pan-Hellenic Black Greek Letter Organizations On African-American Male Students Attending Predominantly White Institutions, Charles R. Smith, Jr. Jan 2019

Examining Persistence: The Influence Of Joining Of Pan-Hellenic Black Greek Letter Organizations On African-American Male Students Attending Predominantly White Institutions, Charles R. Smith, Jr.

Dissertations, Theses, and Masters Projects

The retention of African-American male students at predominantly White institutions is an issue that continues to plague colleges and universities in the United States. African-American men have the lowest college graduation rate of any segment of the population. Pointedly, two-thirds of African-American male students who attend public four-year schools do not graduate within six years. Yet, research highlights how social engagement supports many minority students who find themselves on the campuses of predominantly White institutions. Establishing social connections builds a support system for these students and can prevent social isolation. One manner of social engagement steeped in history is the …


Scattering A Bose-Einstein Condensate Off A Modulated Barrier, Andrew James Pyle Jan 2019

Scattering A Bose-Einstein Condensate Off A Modulated Barrier, Andrew James Pyle

Dissertations, Theses, and Masters Projects

A quantum pump is a device that transports particles through a circuit with localized time-varying potentials, and without the need for an external applied voltage or chemical potential. Quantum pumping was originally proposed in the context of electron transport in nanowires, but has proven difficult to implement. The ultracold atom approach represents a possible route around the current experimental bottleneck. We present an experiment to study 1D quantum mechanical scattering by an amplitude-modulated barrier. This experiment represents a first step toward implementing a quantum pump for ultracold atoms based on two such barriers modulated out of phase with one another. …


Beyond The Standard Model: Flavor Symmetry, Nonperturbative Unification, Quantum Gravity, And Dark Matter, Shikha Chaurasia Jan 2019

Beyond The Standard Model: Flavor Symmetry, Nonperturbative Unification, Quantum Gravity, And Dark Matter, Shikha Chaurasia

Dissertations, Theses, and Masters Projects

Despite the vast success of the Standard Model of particle physics, it is no secret that is also has its shortcomings, thus providing incentive to look beyond the Standard Model for solutions. In this thesis we focus in particular on a model of horizontal flavor symmetry, unification via a universal Landau pole, emergent gravity, and dark matter. First we explain the observed hierarchies in the elementary fermion mass spectrum via a model based on the double tetrahedral group, the smallest discrete subgroup of SU(2), while relaxing previous assumptions of supersymmetry. A sequential symmetry breaking process results in a hierarchy in …


Electronic Properties Of Two-Dimensional Van Der Waals Systems, Yohanes Satrio Gani Jan 2019

Electronic Properties Of Two-Dimensional Van Der Waals Systems, Yohanes Satrio Gani

Dissertations, Theses, and Masters Projects

In this dissertation we study the electronic structure of van der Waals systems. A van der Waals systems is a heterostructure in which the different constituents are held together by van der Waals forces. We study two different types of van der Waals systems: van der Waals systems formed by graphene and a monolayer of NbSe2, van der Waals systems obtained by placing graphene nanoribbons on a two-dimensional crystal. For the first type of systems we build a continuous low-energy effective model that takes into account the presence of a twist angle between graphene and NbSe2, and of spin-orbit coupling …


Investigating The Molecular Choreography Of Atmospherically Relevant Molecules: A Dynamics Study, Kenneth Jacob Blackshaw Jan 2019

Investigating The Molecular Choreography Of Atmospherically Relevant Molecules: A Dynamics Study, Kenneth Jacob Blackshaw

Dissertations, Theses, and Masters Projects

Investigating and understanding the chemistry of the atmosphere has historically been an important research topic. This importance has only strengthened in the recent decades as technological advancements have drastically increased anthropogenic emissions of hydrocarbons and nitroaromatic compounds. Indeed, we are in an era of unprecedented change of the chemical composition of the troposphere and never before has an in-depth understanding of atmospheric chemical properties been more sought-after. This study seeks to fill that need by probing the molecular dynamics of atmospherically relevant molecules through the use of velocity map imaging (VMI). In particular, we utilize VMI to study the photolysis …


Invasive Species Research In Compensatory Wetland Mitigation: Investigating Plant Community Composition And Environmental Correlates With Three Invasive Plants, Dakota Hunter Jan 2019

Invasive Species Research In Compensatory Wetland Mitigation: Investigating Plant Community Composition And Environmental Correlates With Three Invasive Plants, Dakota Hunter

Dissertations, Theses, and Masters Projects

Invasive plant species can alter natural communities and degrade ecosystem function, yet the factors influencing species invasion are poorly understood. Understanding how environmental factors affect plant invasion on compensatory wetland mitigation sites would allow wetland managers to approach invasive species management using a proactive approach (prior to invasion), thus minimizing the likelihood of invasive plants colonizing the system and degrading ecosystem function. In Chapter 1, I introduce the concepts and relevant literature used repeatedly in my project. In Chapter 2, I examine which key environmental factors are associated with altered plant community structure and invasive species prevalence on compensatory wetland …


His Majesty's Ship Saphire And The Royal Navy In 17th-Century Newfoundland, Erika Elizabeth Laanela Jan 2019

His Majesty's Ship Saphire And The Royal Navy In 17th-Century Newfoundland, Erika Elizabeth Laanela

Dissertations, Theses, and Masters Projects

The English fifth-rate frigate Saphire was set on fire by its commander in Newfoundland during an attack by a French squadron in September 1696. Prior to its untimely sinking, this small warship had served the Royal Navy for over two decades, primarily in the Mediterranean, acting as convoy and escort to English shipping. This study combines multiple lines of evidence, including archaeology and material culture recovered from the wreck and contemporary documents, art, and illustrations, to explore the significance of the Saphire through a series of multi-scalar and diachronic interpretive lenses. The approach is inspired by an analytical framework for …


Distress Tolerance Predicts Day-To-Day Emotion Regulation Behaviors, Maria Alexandra Larrazabal Carrillo Jan 2019

Distress Tolerance Predicts Day-To-Day Emotion Regulation Behaviors, Maria Alexandra Larrazabal Carrillo

Dissertations, Theses, and Masters Projects

Distress tolerance (DT), or the ability to effectively withstand aversive internal experiences, is related to diverse physical and mental health benefits, including resilience to depression, anxiety, and substance misuse. DT might prevent health problems by promoting more adaptive and less maladaptive emotion regulation decisions in the face of stressful events. The present study—a pilot investigation that is the basis for a forthcoming study—tested this hypothesis by examining between- and within-person associations of DT with a repertoire of 12 common emotion regulation strategies. We recruited 25 high-anxiety university students to complete surveys of DT and emotion regulation efforts in response to …


A Program Evaluation Of The Reading Mastery Initiative In A Rural Primary School, Michael J. Daddario Jan 2019

A Program Evaluation Of The Reading Mastery Initiative In A Rural Primary School, Michael J. Daddario

Dissertations, Theses, and Masters Projects

Educational success and attainment, and individual sustainability depend on reading ability. School leaders, especially at the elementary and primary level, have great responsibility ensuring student success in learning to read. In this era of standards-based curriculum and high stakes testing and accountability, school leaders must be certain the programs employed to grow student reading ability are successful. This program evaluation analyzes the effects implementing a scripted, direct instruction reading program has had at a rural, primary school. Specifically, this study investigated the correlation between the Scholastic Reading Inventory and the Virginia Third Grade Reading Standards of Learning Assessment, analyzed the …