Doctoral Dissertations (Winter 2014 to Present)

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Celtic nationalism, identity, and ethnicity in Wales and Ireland, 1870-1925
(University of Delaware, 2014) De Barra, Caoimhín
In this dissertation I examine how Irish and Welsh cultural and political nationalists created movements in their respective countries that were based in part upon an idealized notion of similar developments across the Irish Sea. I also explore the extent to which nationalists in both countries embraced the idea that Ireland and Wales should have a special relationship based on their shared Celtic heritage. In chapter one, I demonstrate that efforts to revive the Irish language in the late nineteenth century were heavily influenced by the idea that the Welsh language had once been revived. I show that members of the Gaelic League adopted Welsh tactics to promote Irish, but believed Ireland was superior to Wales in terms of nationality. In chapter two I argue that the development of a distinct Welsh political consciousness was influenced by Irish political nationalism. Welsh political nationalists, I show, wanted to borrow strategies from the Irish Home Rule party and Irish Land League without being accused of importing Irish violence into the principality. In chapter three I demonstrate that Irish nationalists rejected Pan-Celticism in part because the use of Welsh bardic rituals by the Pan-Celts suggested the movement was of an antiquarian, rather than modern, nature. In chapter four I highlight how Pan-Celticism proved to be more popular in Wales than Ireland, partly because the movement championed the Welsh as role models for other Celtic nations to aspire to. In chapter five, I argue that Irish nationalists became more aggressive in asserting Irish nationalist supremacy over Wales, in response to the taunts of David Lloyd George during the Irish War of Independence. At the same time, the conflict in Ireland marked a transition in Welsh nationalist politics, away from championing Welsh Home Rule on liberal principles, toward demanding self-government based on the need to preserve Welsh culture, modeled on the example of Sinn Féin. I conclude that Ireland and Wales each played an important role in the evolution of nationalism in their respective neighbor's country, but that nationalists in each nation believed they were superior to the other in terms of true Celtic nationality.
Just security or a secure justice?: mapping the transitional justice-human security nexus
(University of Delaware, 2014) Balasco, Lauren Marie
This dissertation studies the relationship between transitional justice and human security. Examples of transitional justice include truth commissions, special prosecutions, amnesties, lustration policies, security sector and judicial reforms, as well as memorial and memory projects. Human security refers to the critical (severe) and pervasive (widespread) human threats and situations that could destabilize a state and society. Because I argue that, ultimately, the security of justice is predicated on the actualization of human security, this dissertation examines the extent to which human security - as a claim to justice - is advanced by the implementation of transitional justice mechanisms. Understanding how transitional justice informs human security practices may lead scholars and practitioners to reflect on the widespread assumption that security must be first in place in order for justice to be enacted. My research question problematizes that very assumption and investigates if and how the practice of justice is used to further the work of human security advocates and their agendas. I explore this impact on the three subfields of human security: safety of peoples, development, and rule of law/human rights. Chapter 3 explores the relationship between transitional justice and the safety of peoples by examining the displacement crisis in Colombia. Chapter 4 discusses how transitional justice relates to development by studying the impact of international courts on reparations programs in Guatemala and Uganda. Chapter 5 addresses the impact of transitional justice on rule of law/human rights by discussing the successes and failures of transitional justice in reforming the state to establish the rule of law in Kenya and Peru. In each of these substantive chapters I explore the conceptual and empirical connections between transitional justice and human security by introducing specific analytical frameworks to organize the evidence. My analysis reveals that, unfortunately, the empirical impact of transitional justice on human security initiatives is rather tenuous despite their strong conceptual connections. There is little coordinated effort between transitional justice and human security epistemic communities, despite the fact that victim testimony and claims to justice are often framed around the human insecurities people face in their daily lives. While many countries are adopting TJ mechanisms, these mechanisms rarely take into account persistent human insecurities that could undermine their ultimate goals to prevent the repeat of a violent and authoritarian past and restore the dignity and rights of individuals.
Hydrodynamics, sediment transport and morphodynamics at inlets and river mouths: a numerical investigation
(University of Delaware, 2014) Chen, Jialin
Inlets and river mouths are among the most important coastal zones in terms of their economic, ecological and societal values. However, our current predictive capability on the hydrodynamics, sediment delivery and morphological evolution of inlets and river mouths remains qualitative. The overarching goal of this study is to enhance the physical understanding and model development of inlet/river mouth dynamics. The newly developed nearshore circulation model, SHORECIRC, using a hybrid finite-difference finite-volume TVD-type scheme, is coupled with the wave model SWAN and several sediment transport model. This new nearshore modeling system is called NearCoM-TVD. The capability and limitation of NearCoM-TVD for several coastal applications, including tidal inlet hydrodynamics, nearshore wave-current interaction and sandbar migration are evaluated. ☐ The interactions between waves, tidal currents, and bathymetry near New River Inlet, NC, USA are then investigated to understand the effects on the resulting hydrodynamics and sediment transport. Using NearCoM-TVD, the model is validated with observations of waves and currents at 30 locations, including in a recently dredged navigation channel and a shallower channel, and on the ebb tidal deltas, for a range of flow and offshore wave conditions during May 2012. Model results reveal the existence of a sharp transition of flow field, which coincides with the location of the breaker zone over the ebb tidal deltas. This region is modulated by semi-diurnal tides and by wave intensity. The modeled tidally averaged residual flow patterns show that waves play an important role in generating vortices and landward-directed currents near the inlet entrance. Numerical experiments suggest that these flow patterns are associated with the channel-shoal bathymetry near the inlet, similar to the generation of rip currents. Model results further show that wave intensity and direction play a critical role in controlling the morphological evolution of the ebb tidal deltas. ☐ To further understand the dominant mechanisms controlling the delivery of sediment in a stratified river mouth, a numerical study is carried out using Regional Ocean Modeling System (ROMS) with an idealized river mouth domain. Motivated by a recent multi-institutional study at the mouth of Columbia River (MCR), we first apply the idealized model similar to the high discharge flow condition of MCR during the month of May 2013 when the field observation was conducted. Field observation reveals an interesting asymmetry of near bed turbidity with significantly higher turbidity observed during flood, which follows the landward migrating front. The numerical model captures the observed high turbidity region during flood. Model results further reveal that the high turbidity is associated with significantly higher turbulent kinetic energy (TKE) following the landward-migrating front during flood. An analysis of model results shows that the predicted high near bed TKE level is associated with the stratified two-layer flow established during flood, which is absent during ebb. The newly established idealized river mouth system is quantified by two nondimensional parameters and hence it can be used as an analytical tool to study the flow structures and the resulting turbulent mixing and sediment transport processes for different river mouth systems.
Objects and anxiety in late medieval English writing
(University of Delaware, 2014) Parkin, Gabrielle
In this study I demonstrate that medieval goods were active and often animated participants in the daily lives of medieval individuals. My project demonstrates how, rather than merely giving voice to dead objects, these lively "things" speak about the emotional, sensual, and experiential lives of late medieval men and women. By bringing together a group of seemingly disparate goods--Books of Hours, stone idols and invisible flowers, clothing, and skull cups--I argue that each object provides a spectrum of possible readings for users, who simultaneously interpreted objects as essential to a spiritual and communal existence, while also fearing that goods might inhibit the soul's relationship with the divine. All matter was, in some way, linked with creation and the divine, and as a result objects inherently possessed degrees of agency that might affect the human user. ☐ Chapter One considers how Books of Hours combine animal, plant, and stone matter and join them with prayers and illuminated images to instruct women in proper touching in this life and the next. In Chapter Two I consider worldly and mystical matter in Chaucer's "Second Nun's Tale" to demonstrate how looking at and touching manmade objects can ultimately limit knowledge of the divine. Though Chaucer provides an exemplum in the form of St. Cecile, who requires no contact with goods to realize her destiny of becoming an early Christian martyr, he ultimately concludes that, for less saintly individuals, it is impossible to ignore the senses, and particularly vision, when forming belief. Chapters Three and Four discuss Margery Kempe's worldly and religious attire. I argue that Margery's clothes and tears become a form of livery that reinforces her relationship with the Heavenly household. As a result, her text itself is actually a narrative of cloth, in which she employs a sartorial vocabulary to understand her transition from mother to mystic. In Chapter Five, I focus on the tale of "Albinus and Rosemund" in John Gower's Confessio Amantis and consider how the substance or matter of an object has inherent power, even if it cannot be perceived immediately though senses. In that tale, the central object, a golden and bejeweled cup that was crafted from a human skull, controls the destiny of all the characters.
Optimization and application of proteomic methods for characterization of host cell protein impurities from Chinese hamster ovary cells
(University of Delaware, 2014) Valente, Kristin
Biopharmaceuticals, including monoclonal antibodies (mAbs) and other therapeutic proteins, are typically secreted by Chinese hamster ovary (CHO) cells along with hundreds of endogenous host cell protein (HCP) impurities that must be removed from the therapeutic product for patient safety. Identification and characterization of these extracellular CHO HCPs by proteomic techniques, such as two-dimensional electrophoresis (2DE) and shotgun methods, can aid process design, resulting in improved biopharmaceutical manufacturing operations. ☐ Sample preparation protocols that maximize total protein recovery are fundamental to increasing the utility of proteomic methods and extracellular CHO HCP recovery is particularly challenging due to the relatively low protein concentration. In this work, design of experiment (DOE) methods are presented for optimizing sample preparation parameters, and favorable conditions are demonstrated to vary across different sample types. Additionally, we developed protocols that improve extracellular CHO HCP capture to facilitate analysis by 2DE and shotgun workflows, with optimized precipitation conditions demonstrated to differ between the two techniques. ☐ As biopharmaceutical manufacturing moves towards continuous bioprocessing, it is important to consider the impact of extended culture of CHO cells and therefore this work monitors the extracellular CHO HCP impurity profile over 500 days of culture. Many extracellular CHO HCPs evade clearance during downstream purification due to product association with mAbs or by exhibiting similar retention characteristics to mAbs on chromatographic media. This work characterizes the methods by which specific HCP impurities co-purify with mAbs by exploring mAb association in varied solution conditions and evaluating the retention characteristics of extracellular HCPs across polishing chromatography operations. ☐ In this work, difficult-to-remove HCPs are defined as impurities that exhibit (1) variable expression with cell age, (2) product association with mAbs, or (3) similar retention to mAbs on chromatographic media. In total, 116 difficult-to-remove HCPs were identified, with 10 of these HCPs challenging purification by all three methods. Short interfering RNA (siRNA) technology was applied to reduce expression of one of these HCPs. Because the difficult-to-remove HCPs presented here may persist across purification operations into the final drug product, further investigation is needed to ensure their removal during bioprocessing and improve the safety of biopharmaceuticals.
"Methinks i am not what I was, my soul too is all man": breeches and travesty roles in English comedy, 1660-1737
(University of Delaware, 2014) Knauss, Elizabeth Patricia
By combining the fields of literary analysis, rhetorical studies, gender studies, and theatre history, this project argues for a comprehensive understanding of breeches and travesty roles in Restoration and Early 18th Century comic drama. The majority of the past scholars on this topic, from John Harold Wilson (1958) to Pat Rogers (1982) to Elizabeth Howe (1992), have argued that breeches and travesty characters of this time were one-dimensional roles whose only purpose was to sexually excite male audience members and thereby increase paid audience attendance. A closer examination of the theatrical costuming practices of this time, in conjunction with the persuasive language and actions of these characters and the actresses who played them, reveals a far more complicated situation. When dressed as women, these actresses and characters are frequently rhetorically impotent, unable to affect those around them in a way conducive to their own happiness. But when dressed as men, these women, both the actresses and the characters they play, become powerfully persuasive, thereby taking control of their own lives to ensure their future happiness. ☐ Chapter One reviews current scholarship on this topic to demonstrate the serious lack of judicious evaluation of these roles. Further, Chapter One explains the rationale for a sophistic frame for rhetorical analysis, as well as the rationale for focusing on theories of gender performance. Chapter One also details the theatrical costume history of the period and hypothesizes potential costuming choices for these characters. Chapter Two explores ten plays of this time period that feature unmarried virgins who cross-dress; typically, these heroines disguise themselves to ensure their domestic happiness and secure marriages of their choosing. An analysis of these roles reveals the importance of establishing a male friendship before a romantic attachment for these women. Chapter Three takes a similar approach as Chapter Two, but focuses on nine plays with women who have been seduced or women who are already married. In these instances, the societal constraints that were designed to protect these women have failed them, resulting in loss of reputation or desperately unhappy and sometimes dangerous marriages. These women cross-dress in order to regain control over their own lives despite their precarious positions. Finally, Chapter Four examines historically significant instances of travesty roles (roles that are male characters but have been performed by actresses, whether intended by the playwright or not). In addition to these travesty roles, Chapter Four also explores instances of all-female productions of plays; there is evidence of at least four all-female productions in London during this time, and speculation of more. Chapter Four argues that the decision to stage these plays with only actresses significantly impacts the production and meaning of these plays. Through analysis of cross-dressed casting, Chapter Four recovers the power the actresses had in the theater and their impact on London theatre history. By taking an interdisciplinary approach, this project corrects the historical narrative and asserts the possibilities of gender questioning and female empowerment on the Restoration and early 18th Century stage.
Studies of QSOX, a medically important flavoenzyme: mechanistic insights, searching for inhibitors, and a potential new diagnostic assay
(University of Delaware, 2014) Israel, Benjamin A.
The Quiescin sulfhydryl oxidase (QSOX) enzymes are facile catalysts of disulfide bond formation in reduced, unfolded proteins. They are a family of flavoenzymes with emerging, medically-relevant biological roles. Recent studies have demonstrated the utility of QSOX as a diagnostic biomarker for pancreatic cancer and certain types of heart failure, and several reports have begun to characterize the roles of QSOX in promoting the invasiveness of a number of different cancers. In the first portion of this work we explore an in-depth understanding the catalytic mechanism of the simplest of the QSOX enzymes, from Trypanosoma brucei. After developing a novel substrate analog, we obtained results that suggest that QSOX does not have a significant prototypical substrate binding site. Methods were also developed to measure, for the first time, the redox potentials of all three redox centers of QSOX. This study revealed an unexpected redox potential mismatch in the mechanism. Mutagenesis studies provided data suggesting a novel mechanism that QSOX and the unrelated DsbA/B system use to bypass apparent thermodynamic barriers to catalysis. Next, work toward the discovery and development of QSOX inhibitors is discussed. Two new, sensitive assays for the enzymes are developed and utilized for high-throughput screening of small molecule libraries. The negative results of this screening effort, combined with our earlier mechanistic studies led to our pursuance of antibody-based inhibitors. Early achievements toward this collaborative project are presented. Finally we adapt and implement the new, sensitive, fluorescence-based assay for QSOX activity in biological samples. This study found, surprisingly, that QSOX activity is relatively abundant in normal adult blood, and provides implications for the utilization of our assay for diagnostic purposes.
Imagining a borderlands south: literature from Mexico and the United Utates, 1845-1950
(University of Delaware, 2014) Hasler-Brooks, Kerry
Imagining a Borderlands South: Literature from Mexico and the United States, 1845-1950 grounds study of the global south in the too often neglected southern space of the borderlands. Building on recent scholarship to restore neglected political, economic, and literary exchanges between Mexico and the U.S., this study considers a group of writers who transcended the geopolitical, cultural, lingual, and racial borders dividing the nations. In the years surrounding the U.S.-Mexican War, U.S. Civil War, and Mexican Revolution, rhetorics of racial singularity, specifically U.S. whiteness and Mexican mestizoness, dominated national politics and public opinion. Against all of this, writers like James Russell Lowell, María Amparo Ruiz de Burton, Katherine Anne Porter, Anita Scott Coleman, Xavier Villaurrutia, Langston Hughes, Jovita Gonzalez, and Margaret Eimer represent a group of intellectuals and artists who rejected the strict national and racial identities imposed by Mexico and the U.S. and in their writing pursued multiple and flexible expressions of identity in the borderlands south. This project revises the traditional landscape of southern studies as it explores a south defined by constantly shifting boundaries, peoples, and histories; restores the historical relationship between Mexico and the U.S. South; and transcends the national, regional, and racial boundaries of traditional Southern literature to include often neglected Mexican, Mexican-American, and African-American voices.
Development of the silyl-heck reaction: preparation of organosilanes via the transition metal-catalyzed silylation of alkenes
(University of Delaware, 2014) Schwanger Martin, Sara Evelyn
Vinyl and allyl silanes are highly useful reagents in organic synthesis. Due to their nucleophilicity, vinyl and allyl silanes stand out as particularly useful synthetic intermediates that can be applied in many transformations, including Hiyama cross-coupling, Fleming-Tamao oxidation, and Hosomi-Sakurai crotylation. There are a number of routes to access these valuable intermediates. However, prior to our work, few routes could access allyl and vinyl silanes directly from stable, widely available, inexpensive alkenes. We sought to use alkenes as a starting point for vinyl and allyl silane formation, and we have used Heck arylation as our conceptual platform to accomplish this goal. ☐ This dissertation will describe the discovery and development of transition metal-catalyzed methods to form unsaturated organosilanes from simple alkene starting materials and silyl halides. We have developed the first high yielding silyl-Heck reactions of alkenes with silyl halides (X= I, Br, Cl, OTf) to form vinyl silanes, using palladium- and nickel-based catalysts. We have also developed a silyl-Heck reaction to form allyl silanes using palladium catalysis. Additionally, we have developed a synthesis of vinyl silyl ethers from alkenes and silyl ditriflates. Finally, we are working toward developing silyl-Heck-like multi-component reactions of silyl triflates, dialkylzinc reagents, and 1,2- and 1,3-dienes and alkynes to form chiral vinyl and allyl silanes and trisubstituted vinyl silyl ethers.
The podium in print: the popular lecture in American literary culture, 1865-1914
(University of Delaware, 2014) Garnett, Virginia L.
The popular lecture and the industry that supported it played a vital role in postbellum authorship and American literary culture. The lecture platform often served as an agent for the promotion, dissemination, and critical evaluation of printed works, at once complementing and rivaling the publishing industry in its defining of authorial celebrity and literary forms. Supported by a print-based network of advertisements, transcriptions, and reviews, the lecture platform not only gave authors another forum for promoting their books, but it also gave readers more direct access to literary figures—a point of contact that provided readers with additional opportunities to influence the literary market. My project, The Podium in Print, examines the resulting shift in author-reader relations from the perspective of lecture bureaus, the popular press, and authors such as Edith Wharton, Henry James, and Mark Twain to determine to what extent contemporary debates about the social value of lecture culture—which often pitted oratory against print—were motivated by self interest. In short, I argue that these media were only at odds in the minds of those invested in creating, maintaining, or challenging intellectual hierarchies. ☐ Despite the prevalence of literary speakers and the broad range of literary topics on the circuit, literary scholars tend to overlook the platform’s centrality to nineteenth-century authorship and the literary marketplace. The popular lecture, when discussed by literary scholars, is generally considered a supplement to literary history, a vehicle through which to examine an individual author’s larger body of work or biography. With the exception of Mark Twain, whose platform career has generated fruitful discussion in many book-length studies, lectures by the likes of Louisa May Alcott, William Dean Howells, and Jack London are read as mere essays, collapsed into the author’s oeuvre, with their tours examined as historical events unto themselves. And while such readings are valuable, their focus on individual authors often highlights the author’s exceptionalism without considering the degree to which his or her experience was dictated by a vast commercial structure within (and against) which all postbellum authors had to operate. ☐ In the introductory chapter, “Nineteenth-Century Platform Culture and American Literary Studies,” I outline the major claims and parameters of this study, engaging with current scholarship on lecture culture, authorship, print culture, and media studies, while asserting the need for a closer attention to the interconnectedness of orality and print in the postbellum literary marketplace. Chapter two, “The Author on Stage: James Redpath and the Promotion of the ‘Literary’ Lecture,” describes the means by which the Redpath Lyceum Bureau created new opportunities for readers to connect with authors such as Mark Twain and Charles Dickens through dramatic readings, personal reminiscences, historical readings, or literary criticism. These platform performances, I argue, defined future readers’ expectations of literature and authorship. Travel writer and widely popular lecturer on the Adirondacks Rev. William H. H. Murray capitalized especially on the access afforded by the platform; my third chapter, “With Press and Paddle,” draws on Murray’s career to demonstrate the platform’s role in negotiating tensions between print and oratory, private study and lived experience. Chapters four and five examine literary representations of lecture culture and discuss the ways authors fought for literary dominance. In “Fixed in Print: The Legible Lecturer in Henry James’s The Bostonians,” I read James’s novel as a site for tracing concerns about the commercial platform, public exposure, and the fixity of print. My reading draws parallels between printed and oratorical space, positing that success on the platform necessarily results in an imprinting of that profession on both the speaker’s body and subsequent printed personas. In my final chapter, “‘Doing It for the Baby’: Edith Wharton and the Trouble with Women on the Platform,” I situate Wharton’s short stories “The Pelican” and the “Legend” in an ongoing conversation about the relative value of useful over abstract knowledge, in which the lecture was considered a lesser intellectual enterprise. ☐ A century after the supposed death of the lecture, we are still drawn to related educative forms. TED Talks, short for Technology, Entertainment, and Design, which strives to bring the most authoritative and dynamic speakers before the public, serves as a sort of modern lyceum, seeking to educate, inspire, and entertain its audience. Functioning much in the same way that nineteenth-century lectures did, the TED forum provides audience members opportunities to engage with speakers like Isabel Allende, Steve Jobs, and J. J. Abrams, thereby tapping into a rich tradition of public speaking and showmanship. Questions about the relative merits of oratory and print have expanded to include aural and visual media, and the formally print-based means of promotion and dissemination have been replaced with a multimodal interface. I conclude my dissertation by arguing that our twenty-first century ambivalence about competing media and lamentations for the death of the printed word reflect an intellectual struggle ongoing since the nineteenth century.
An investigation of strategies to improve under-enrolled programs
(University of Delaware, 2014) Harrison, Chad Edward
This report describes strategies that I implemented as an assistant principal at a Technical High School (henceforth referred to as "The Technical High School"), which provides specific vocational/technical training in sixteen different Career & Technical Education (CTE) programs. The problem I addressed was how to successfully compete for students with other magnet schools that offer CTE programs. Business Technology, a CTE program for which I had administrative responsibility is one of the lowest subscribed CTE programs in the State. ☐ As a newly appointed assistant principal and supervisor of the CTE programs at The Technical High School, I had limited time to make a difference and chose several approaches. One was to survey all students in the school about their satisfaction with their current program, the factors that led to their choice of program, and what about their program they would recommend to a friend who was considering the same program. I considered two alternative programs, the National Academy Foundations (NAF) curriculum model and Project-Based Learning. The latter was selected as a better fit for the school. Professional development and instructional technology were also allocated to support the teacher and instruction. I implemented a better marketing strategy to attract students to the Business Technology program. ☐ When I looked more closely at the Business Technology program, I discovered a number of complaints about the instructor from parents and students, and also that it received relatively low survey satisfaction scores. Furthermore, the program was distinctive in that the majority of students in the program had not selected it as their first choice. The surveys revealed, overall, that students who were enrolled in their second choice program gave less favorable ratings and rankings to the survey items and had lower GPAs, DCAS levels, higher absentee rates and disciplinary incidents. Prior to this work, the faculty and staff of the school were unaware of the adverse effects of placing students into program areas that were not their first choice. ☐ I further reflected on the improvement effort results and learned that adequate planning time should be allocated before adopting and implementing a new program. Additionally, professional development is necessary to successfully train an instructor in facilitating a career program using Project-Based Learning. Expertise from industry is also necessary to fully implement a CTE program model with diverse areas of learning, such as the model selected for Business Technology. A review of the survey results suggests that the school district in which I am employed (henceforth referred to as "The Technical School District") should review other CTE programs that may be more problematic than Business Technology.
The influence of community social institutions on individual disaster recovery: a multilevel analysis
(University of Delaware, 2014) Clay, Lauren A.
Social capital, defined as “the norms and networks that facilitate collective action” or the “resources embedded in social networks and social structure that can be mobilized by actors”, is a critical component of disaster recovery and resilience (R. Dynes, 2006). Social capital is viewed by disaster scholars as essential for responding to the new and unexpected problems that arise in disasters (R. Dynes, 2006) and is distinct from other types of capital that communities maintain. Social capital is less affected than physical and human capital in a disaster as it is not a physical asset that can be damaged in a hazard event. Consequently, social capital is a critical preexisting resource that can be leveraged in a disaster to respond to the novel problems that arise rather than setting up new systems, structures, and norms solely for emergency response purposes (R. Dynes, 2006). Establishing a mechanism where communities can foster collective responsibility, identify community capacities, and become involved in planning increases social capital (R. Dynes, 2006; Norris, Stevens, Pfefferbaum, Wyche, & Pfefferbaum, 2008). Social capital has been viewed as powerful for influencing community recovery, even more important than the level of aid a community receives (Aldrich, 2010). ☐ I hypothesize that communities with greater numbers and diversity of community social institutions provide greater opportunities for individuals to interact to build networks and relationships in their communities. Social institutions are a quantifiable mechanism for building social capital at the community level. This community social capital can be leveraged following a disaster to take the collective action necessary for recovery. ☐ This dissertation examines on the influence of a community’s social fabric on individual disaster recovery by examining the impact of the quantity, types, and diversity of social institutions present in a community on individual disaster recovery. I base this line of inquiry on two assumptions. First, neighborhoods matter. They influence a wide range of community and individual health outcomes, including disaster recovery. Second, community factors such as social capital also influence disaster recovery. ☐ Social and physical neighborhood disorder may act as a barrier to developing social cohesion and social capital, both of which contribute to better social organization and collaboration among community groups, in turn contributing to better disaster recovery outcomes (Bates & Peacock, 1989; P. R. Berke, Kartez, & Wenger, 1993; A. Curtis & Mills, 2011).To further explore the role of community social institutions in the context of disaster recovery this study examines the influence of social institutions on disaster recovery outcomes and on perceptions of social and physical disorder then discusses the results in the context of disaster recovery. ☐ Hierarchical logistic and linear modeling were used to investigate the contextual effects of community social institutions on disaster recovery outcomes and the upstream impact of neighborhood social and physical disorder on community social institutions in a sample of households heavily impacted by Hurricane Katrina. Recovery data was obtained through a collaboration with the National Center for Disaster Preparedness using data from the Gulf Coast Child and Family Health Study conducted between 2006 and 2010. Social institutions data was obtained from the Dun and Bradstreet Million Dollar Database and includes data on institutions such as libraries, schools, medical facilities, and civic, professional, and religious groups. Analyses were conducted using ArcGIS 10.1 and Stata 13.1. ☐ When exploring the influence of community social institutions, a proxy for social capital in the community, we found community level social capital had little impact on individual disaster recovery outcomes. Certain individual level factors are strongly associated with positive disaster recovery outcomes. At the individual level, we found that social support, self-efficacy, income, and food security are important for better recovery outcomes. In general, people recover better following disasters when they have enough food and money and they feel like they have the skills and resources to handle the situation. This study takes an important step to break up the construct of social capital and explore its influence at multiple levels. Additional studies are needed to continue to learn more about the nuances of social capital in communities given the recent focus on it as a potential panacea to disaster recovery. Dynes describes social capital as a community level construct that accumulates at the community level (R. Dynes, 2005; R. Dynes, 2006). Our study finds that this effect does not trickle down to influence individual level disaster recovery outcomes. This raises concerns about overemphasizing social capital as the solution that communities can focus on building prior to a disaster and that will make recovery easier, faster, or result in better outcomes. Given the lack of influence on individual level outcomes, the concern is that those that are most vulnerable in a disaster will not receive the appropriate support – financial, food, or reconnecting with social networks – to recover at the household level. ☐ Of 793 families participating in the Gulf Coast Child and Family Health Study that completed the neighborhood disorder survey in 2010, 385 (48.55 percent) report problems with social disorder and 349 (44.01 percent) report problems with physical disorder in their neighborhoods. Community social institutions are not associated with reports of social and physical neighborhood disorder in this study sample. Individual and community level characteristics, however were found to be associated with reports of neighborhood disorder. An examination of the ecological level community characteristics revealed that male population was statistically significantly associated with social disorder. We also observed that households that have their basic needs met such as sufficient income, stable housing, and home ownership do not live in areas with high levels of social or physical disorder. ☐ These findings expose one of the perpetual tensions in concepts of recovery, that the fates of individuals and households can be very different than that of the community as a whole. The implications of this evidence for policy makers is that they must maintain an ambidextrous approach to disaster recovery planning and activities in terms of what scales they wish to make an impact. At the community level there may be value in community based institutions however individual recovery trajectories are determined by individual level characteristics such as income and employment, housing, and household make up that are not easily manipulated by policy interventions. One implication of this which is suggested by both this study and other literature is that policy makers and emergency managers should orient their recovery planning around how to connect people who are generally underserved with community based organizations to meet their needs in the absence of disaster as it is community development in the absence of disaster that is the path to improving disaster resilience (Norris 2008). Faith in social capital is not going to be the panacea that delivers us to community recovery and resilience at least not without a more nuanced understanding of the scale in which it plays out. ☐ This study builds on the existing disaster science scholarship by adding a novel measure of community social institutions as a mechanism for building social capital that can be aggregated to any meaningful scale of analysis and includes a more comprehensive set of social institutions than previous research studies. Applying a measure of community social institutions to individual level disaster recovery outcomes data using both survey and administrative data to empirically investigate the relationship between factors at different levels of analysis takes an important step towards addressing existing gaps in the literature on disaster recovery, social institutions, and social capital.
Microtubule-associated CAP-Gly domain of dynactin: structure, dynamics, conformational plasticity, and interactions with microtubules and microtubule plus-end tracking proteins by magic angle spinning NMR spectroscopy
(University of Delaware, 2014) Yan, Si
Microtubules and their associated proteins play essential roles in a broad range of physiological functions, including cell migration, mitosis, polarization, differentiation, and vesicle and organelle transport. The malfunctions of microtubule-associated proteins are related to numerous diseases. Despite the importance of this system, the mechanisms of the interactions between microtubules and their associated proteins are still not fully understood, especially on the atomic-resolution level. The assemblies formed by microtubules and their associated proteins are large, insoluble and lack long-range order, which precludes their atomic-level structure and dynamic characterization by the two most prevalent structural biology techniques, X-ray crystallography and solution NMR spectroscopy. ☐ Magic angle spinning (MAS) NMR spectroscopy is an approach uniquely suited for gaining atomic-level information into the structure and dynamics of assemblies of microtubules with their associated proteins, because it does not require solubility or long-range order, and there are no limitations on the molecular weight of the system under investigation. The focus of this dissertation is gaining comprehensive structural and dynamics insights into the p150Glued CAP-Gly domain of mammalian dynactin, and understanding its interactions with microtubules and microtubule plus-end tracking proteins, by MAS NMR spectroscopy. ☐ Using MAS NMR spectroscopy, we have obtained high-quality three-dimensional structures of the CAP-Gly domain in the unbound state (Chapter 3). We have investigated the interactions of the CAP-Gly domain with a microtubule plus-end tracking protein EB1 (Chapter 4). We have solved the first atomic-resolution 3D structure of the CAP-Gly assembled on microtubules (Chapter 5). In addition to the structural studies of the CAP-Gly domain, we have performed internal dynamics studies of free CAP-Gly, CAP-Gly assembled on microtubules and CAP-Gly in complex with EB1 (Chapter 6). With these structural and dynamic investigations of free CAP-Gly and CAP-Gly in complex with microtubules or with its binding partner, we have discovered the unique conformational plasticity of the CAP-Gly domain, which we postulate to be essential for its ability to walk along microtubules and to interact with its various binding partners to regulate microtubule dynamics. ☐ The studies detailed in this dissertation serve as an important step towards our long-term goal, which is to decipher the regulation mechanisms of microtubule-based intracellular transport mechanisms at atomic resolution, using MAS NMR spectroscopy and other biophysical techniques.
Emanuel de witte's sermon paintings: sight, sound and spirituality
(University of Delaware, 2014) Bordeaux, Sara Rachel
This dissertation proposes a revised view of Emanuel de Witte's Calvinist church interior paintings as sites of spirituality that evoke the sensory experience of attending church. Calvin's objection to devotional art precipitated the traditional understanding of these paintings as perspectives, which privileges their architectural elements and diminishes their spirituality. Because paintings by De Witte and his contemporaries represent structures recently stripped of most Catholic accoutrements, art historians have described them as spare spaces fit for a faith based solely on scripture. However, De Witte's sermon paintings assert Calvinist presence by showing the Reformed faithful at worship. De Witte utilizes paint to evoke the experiences of looking and listening, which encourages the viewer-as-congregant to attend the painted service. I suggest that we may identify a distinctly Reformed image in the subject matter, style, and technique of De Witte's paintings, which introduce a new visual and aural vocabulary to represent an aniconic faith. This dissertation fills a lacuna in the scholarship on Emanuel de Witte, whose oeuvre has not been the sole subject of study since Ilse Manke's 1963 monograph. Whereas De Witte's brief career in Delft has received attention in abundant literature on the Delft School, my focus on his Amsterdam paintings enhances our understanding of Calvinist identity and worship in Amsterdam's multiconfessional environment. My exploration of the sensory appeal of De Witte's paintings recasts Calvinism in Early Modern Europe as a profoundly experiential faith. In light of the Calvinist Church's mutability during the seventeenth century, it is possible that De Witte's paintings contribute to the formation of Dutch Calvinist identity by picturing the Reformed congregation practicing their faith. De Witte's paintings may be understood as a fundamentally new kind of religious art that depicts sacred spaces activated by the communities within them. His painted sermons represent the Word made image.
Sparse signal processing for machine learning and computer vision
(University of Delaware, 2014) Zhou, Yin
Signal sparse representation solves inverse problems to find succinct expressions of data samples as a linear combination of a few atoms in the dictionary or codebook. This model has proven effective in image restoration, denoising, inpainting, compression, pattern classification and automatic unsupervised feature learning. Many classical sparse coding algorithms have exorbitant computational complexity in solving the sparse solution, which hinders their applicability in real-world large-scale machine learning and computer vision problems. In this dissertation, we will first present a family of locality-constrained dictionary learning algorithms, which can be seen as a special case of sparse coding. Compared to classical sparse coding, locality-constrained coding has closed-form solution and is much more computationally efficient. In addition, the locality-preserving property enables the newly proposed algorithms to better exploit the geometric structures of data manifold. Experimental results demonstrate that our algorithms are capable of achieving superior classification performance with substantially higher efficiency, compared to sparse-coding based dictionary algorithms. Sparse coding is an effective building block of learning visual features. A good feature representation is critical for machine learning algorithms to achieve satisfactory results. In recent years, unsupervised feature learning has received increasing research interest in various computer vision and pattern recognition problems. Unlike humanengineered feature extractors that typically require domain knowledge and a large amount of labeled data, unsupervised learning algorithms are generic and designed to automatically discover the intrinsic patterns from the abundant unlabeled data that are usually readily available (from Internet) and require no laborious human labeling. In this dissertation, we will explore the capability of feature learning algorithms in automated biomedical image analysis. Specifically, we will present two unsupervised feature learning models for histopathology image classification. We will also introduce a novel convolutional regression model for nuclei segmentation. Experiments on biomedical image classification and segmentation benchmarks demonstrate that the proposed feature learning systems can achieve very competitive results compared to dedicated systems incorporating biological prior knowledge. Finally, we propose a sparse coding based framework for classifying complicated human gestures represented as multi-variate time series (MTS). Specifically, we will present a novel feature extraction strategy, which can overcome the problem of inconsistent lengths among MTS data and is robust to the large variability within human gestures. Moreover, we will introduce a generic approach to kernelize sparse representation, which leads to enhanced classification performance. Extensive experiments verify the effectiveness of the proposed framework.
Information retrieval for reducing manual effort in biomedical and clinical research
(University of Delaware, 2014) Zhu, Dongqing
Medical professionals leverage health-related data to address questions and support decision-makings. However, many of these medical tasks require intensive manual effort in identifying useful information in the noisy data. The rapid growth of data is making these tasks more and more costly and time-consuming. In this thesis, we develop effective medical information retrieval (IR) systems to reduce search-related manual work for three representative medical related tasks, namely electronic medical records (EMR) based cohort identification, Medical Subject Headings (MeSH) indexing, and gene ontology annotation (GOA). For cohort identification, we improve the search precision and recall from three aspects: 1) we design a multi-level evidence aggregation strategy for effective merging and scoring of the distributed evidence in EMR; 2) we develop a novel statistical IR model that significantly alleviates two medical language related issues in medical IR; 3) we further enhance the search performance by effectively incorporating domain knowledge into our system. For MeSH indexing and GOA, we demonstrate how to use IR to address specific needs. In particular, we investigate different query formulation methods and explore various ways in which IR work together with other techniques such as Natural Language Processing and Machine Learning.
Pore-scale considerations of the air-water interface or rough surface on flow in porous media
(University of Delaware, 2014) Zheng, Wenjuan
Understanding flow in porous media is a challenging problem in many fields of fundamental science and engineering. This dissertation focuses on flow behavior at the pore scale, including observation and simulation of flow in microchannels and development of pore-space-based models for unsaturated hydraulic conductivity. Pore-scale flow is strongly influenced by relatively large interfacial areas (per unit volume) where surface tension, viscosity, and diffusion processes dominate gravity and inertia. Consequently, flow regimes may differ markedly from conventional large-scale flows. In Chapter 2, I presented water flow patterns visualized in open capillary channels with various sizes using the μ-PIV technique. I found that a partial-slip, rather than the commonly used stress-free condition, provided a more accurate description of the boundary condition at the air-water interface (AWI). The mechanism for a partial slip boundary condition at the AWI is due to the confinement of adjoining solid walls. In Chapter 3, I demonstrated that assuming a partial-slip AWI for corner flow could improve the prediction of unsaturated hydraulic conductivity at low water saturation conditions compared to that with a shear-free AWI. A roughness triangular pore space model (R-TPSM) for water retention and unsaturated hydraulic conductivity was developed in Chapter 4. The R-TPSM takes into account surface roughness effects where film flow largely increased at low water content. The model was able to significantly improve the prediction of unsaturated hydraulic conductivity for heavier-textured soils (e.g., loam). In Chapter 5, the slip boundary condition at rough surfaces was resolved numerically at the pore scale. Roughness scale, together with interfacial shape and local slip length at the liquid-gas interfaces, and particularly the coupled effect of the last two, affect the effective slip length on the rough surfaces. Improved physical understanding of surface/interface effects on multiphase flow behavior at both the pore scale and the core scale has been achieved in this study. Findings in this study are essential for an accurate quantification of a wide variety of multiphase problems in porous media as well as for design and manipulation of flow in microfluidics.
Transition metal catalysis of acetals and pivalates: enantioselective and enantiospecific methods for C-C & C-B bond formation
(University of Delaware, 2014) Harathi Dwarakanath, Srinivas
This dissertation focuses on the development of transition metal-catalyzed reactions of acetal and pivalate substrates. These new methods enable efficient synthesis of highly enantioenriched organic molecules. The first chapter discusses an enantioselective alkynylation of chromene acetals using copper (I) catalysts. In this method, we have observed wide substrate scope, and high enantioselectivities were observed especially with 4-aryl chromene acetals. Use of dilute conditions, BF 3 OEt2 as Lewis acid and Cy2 NMe as base are critical for achieving high enantioselectivities. In this chapter, a mechanism and stereochemical model are proposed that rationalize the observed substituent effects and enantioselectivities. This method demonstrates the advantage of using transition metal catalysis to facilitate reactions involving oxocarbenium ion intermediates. Chapter 2 discusses enantiospecific, nickel-catalyzed cross-couplings of benzylic pivalates with mild and functional group tolerant arylboroxines as cross-coupling partners. The diarylalkane and triarylmethane products formed were obtained in high yields and levels of stereochemical fidelity. The success of this method depends on the use of Ni(cod) 2 as catalyst and NaOMe as base. In this method, we have shown broad substrate scope and wide functional group tolerance. Chapter 3 discusses an enantiospecific, nickel-catalyzed cross-coupling of 1,3-disubstituted secondary allylic pivalates with mild and functional group tolerant arylboroxines. The 1,3-diaryl allyl products are obtained with high levels of stereochemical fidelity and yields. Excellent regioselectivity and E/Z selectivity are also observed in this method. A wide variety of functional groups are tolerated, and the utility of this method is demonstrated in the synthesis of the anti-inflammatory drug (S )-ketoprofen. Chapter 4 discusses an enantiospecific, nickel-catalyzed cross-coupling of 1,3-disubstituted secondary allylic pivalates and bis(pinacolato)diboron (B2 Pin2 ) to form γ-aryl allyl boronates in high yields and ee's. In this method, the absolute configuration of the allylboronate product depends on the ligand and the solvent used. Thus, either enantiomer of allyl boronate is available from the same enantiomer of pivalate starting material. The optimized conditions for obtaining both retention and inversion products are discussed.
Developing learning outcomes for Resident Assistant training
(University of Delaware, 2014) Diesner, Michael R.
Outcomes have not been defined for the Resident Assistant (RA) position at Towson University. The absence of these learning outcomes contributes to the RAs' inability to articulate what knowledge and skills they gained from the job. Consequently, many students may be falling short of their potential for learning and growth. To define said outcomes, various approaches to learning outcomes in higher education, leadership development, and self-authorship were explored, including the work of Warren Bennis, George Kuh, and Marcia B. Baxter Magolda. In addition, Towson University Housing and Residence Life artifacts and documents related to the Resident Assistant position were collected and analyzed. Interviews and a focus group were conducted with select members of the Housing and Residence Life staff to determine the various perspectives on what a Resident Assistant should be learning from their experience. Professional staff members and Resident Assistants were included in the study. Several inconsistencies were found among the collected documents and artifacts, but the interviews and focus group provided many points of agreement about what knowledge and skills the Resident Assistant position should provide for students. An ability to work with and communicate with others, specifically individuals different from oneself, emerged as the most valuable skills a student can gain. Nineteen learning outcomes for first-year Resident Assistants and eight learning outcomes for second- and third-year Resident Assistants are proposed in the following domains: communication, diversity, administrative skills, teamwork, conflict and crisis management, and community building. An online portfolio to collect individual Resident Assistant artifacts and reflections, a revised Resident Assistant course syllabus, and an outcome-driven training schedule are also proposed to introduce and reinforce the learning outcomes throughout the Resident Assistant experience.
Synthesis and reactivity of acetyl coenzyme A synthase active site analogues
(University of Delaware, 2014) Shalaida, Megan P.
Acetyl coenzyme A synthase (ACS) produces acetyl coenzyme A (acetyl-CoA) by combining CH3 from a methylated corrinoid iron-sulfur protein (CH3 -CoFeSP), CO from carbon monoxide dehydrogenase (COdH) and coenzyme A (CoA). Biologically unprecedented nickel-methyl, nickel-carbonyl, and acetyl-nickel intermediates are proposed to occur during catalysis. To probe the feasibility of Ni(II)Ni(I) or Ni(II)Ni(0) intermediates during catalysis, the synthesis of a dinucleating thiol macrocycle with asymmetric coordination sites was targeted. En route to this ligand, a series of mononuclear nickel thiol-based Schiff base complexes, N,N '-bis(3-methoxycarbonylthiosalicylidene)-R-diaminonickel(II) (Ni(3-MOC-tsalR)) where R = 1,2- diaminoethane (en), 1,3-diaminopropane (pr), 1,4-diaminobutane (but), 1,2-phenylenediamine (phen), and 4,5- dimethyl-1,2-phenylenediamine (dimph), were synthesized. The resultant square-planar complexes were characterized spectroscopically and crystallographically. Cyclic voltammetry studies of Ni(3-MOC-tsalR) (R = en, pr, but) showed one reversible cathodic wave, assigned as the Ni(II)/Ni(I) reduction. Studies of Ni(3-MOCtsalR) (R = phen, dimph) exhibited an irreversible cathodic peak assigned as a ligand reduction. Attempts to synthesize the asymmetric dinucleating thiol macrocycle using various starting diamines and starting materials at different temperatures and reaction times all failed to produce the desired product. The tridentate ligand bis[2-(isopropylthio)ethyl]phenylphosphine (S iPr PSi Pr , (PhP(CH2 CH2 SPri ) 2 )) with two thioether donors has been used to investigate the mechanism of methyl transfer. Reaction of Si Pr PSiPr with Ni(cod) 2 (cod = 1,5-cyclooctadiene) and two equivalents of triphenylphosphine (PPh3 ) generated (κ2 - Si Pr PSiPr )Ni(PPh 3 )2 . The resultant tetrahedral complex was characterized spectroscopically and crystallographically. (κ2 - S iPr PSi Pr )Ni(PPh3 )2 was found to decompose over time in solution to (κ2 -Si Pr PS)2 Ni. The alkyl transfer reactivity of (κ 2 - SiPr PS iPr )Ni(PPh3 )2 was assayed through reactions with alkylcobaloximes, i.e., methyl, methyl-d3 , ethyl, isopropyl and neopentyl. The reaction of methyl and methyl-d3 derivatives of RCo(dmgBF2 )2 py (dmgBF2 = (difluoroboryl)dimethylglyoximato, py = pyridine) with (κ2 - SiPr PS iPr )Ni(PPh3 )2 proceeded in quantitative spectroscopic yields forming the respective alkyl species, [(κ2-SiPr PS iPr )Ni(PPh3 )R]+ (R = Ch3 or CD3 ) and [Co(dmgBF2 )2PPh 3 ]- . Reactions of (κ2 - S iPr PSi Pr )Ni(PPh3 )2 with RCo(dmgBF2 ) 2 py, where R = Ch3 CH2 or CH(Ch3 ) 2 , yielded ethylene and propylene, respectively, rather than the corresponding Ni-alkyl complex, implicating successful alkyl transfer followed by facile β-hydrogen elimination for these nickel complexes. Kinetics data obtained for the transfer of alkyls (Ch 3 , Ch3 CH2 ) to (κ2- S iPr PSi Pr )Ni(PPh3 )2 supports an SN 2 mechanism similar to that found in the enzyme.

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