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Stereoselective Radical Transformations by Co(II)-Based Metalloradical Catalysis:
No full textThesis advisor: X. Peter ZhangChapter 1. Co(II)-Based Metalloradical Catalysis for Stereoselective Radical Cyclopropanation of Alkenes
This Account summarizes our group’s recent efforts in developing metalloradical catalysis as a one-electron approach for catalytic radical cyclopropanation of alkenes with diazo compounds.
Chapter 2. Asymmetric Radical Process for General Synthesis of Chiral Heteroaryl Cyclopropanes
We have developed a Co(II)-based metalloradical system that is highly effective for asymmetric radical cyclopropanation of alkenes with in situ-generated heteroaryldiazomethanes. Through fine-tuning the cavity-like environments of newly developed D2-symmetric chiral amidoporphyrins as the supporting ligand, the optimized Co(II)-based metalloradical system is broadly applicable to pyridyl and other heteroaryldiazomethanes for asymmetric cyclopropanation of a wide range of alkenes, providing general access to valuable chiral heteroaryl cyclopropanes in high yields with excellent diastereoselectivities and enantioselectivities.
Chapter 3. Enantioselective Metalloradical 1,6-C–H Alkylation of In Situ-Generated Alkyldiazomethanes for Synthesis of Chiral Piperidines
We have disclosed an effective Co(II)-based metalloradical system as a fundamentally different approach to harness the potential of 1,6-HAA radical process, enabling asymmetric 1,6-C–H alkylation of in situ-generated alkyldiazomethanes to construct chiral piperidines. Supported by an optimal D2-symmetric chiral amidoporphyrin ligand, the Co(II)-catalyzed alkylation system is capable of activating a wide array of alkyldiazomethanes containing C(sp3)–H bonds with varied steric and electronic properties, providing access to chiral piperidines in good to high yields with high enantioselectivities from readily accessible 4-aminobutanal derivatives. In addition to practical attributes, such as operational simplicity and mild conditions, the metalloradical system is highlighted by its tolerance to different functional groups as well as compatibility with heteroaryl units.
Chapter 4. Design and Synthesis of A Novel D2-Symmetric Chiral Porphyrin for Co(II)-Based Metalloradical Catalysis
A novel D2-symmetric chiral amidoporphyrin derived from chiral cyclopropanecarboxamide containing diphenyl units has been effectively constructed based on Co(II)-catalyzed asymmetric cyclopropanation of alkenes.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Chemistry
Three Essays in Corporate and Entrepreneurial Finance:
Get PDFThesis advisor: Thomas J. ChemmanurMy dissertation consists of three chapters. In the first chapter, I study the impact of a place-based tax credit policy, the Opportunity Zone program created under the Tax Cuts and Jobs Act of 2017, on local private investments and entrepreneurship. Using a difference-in-differences approach and comparing census tracts designated as Opportunity Zones and other eligible but non-designated tracts, I find that the policy has drawn significantly more private investments to economically distressed areas. Surprisingly, however, these private investments have led to decreases in local new business registration. The decrease in entrepreneurship was mainly in the non-tradable sector, which is more sensitive to local conditions than the tradable or construction sector. Further robustness tests suggest that the above results are causal. I provide one explanation for the above findings that more private investments went to existing and older firms in Opportunity Zones, discouraging potential entrepreneurs from competing with the better-financed firms locally.
In the second chapter, I examine how changes in investor protection regulations affect local entrepreneurial activity, relying on the heterogeneous impact of a 2011 SEC regulation change on the definition of accredited investors across U.S. cities. Using a difference-in-differences approach, I show that cities more affected by the regulation change experienced a significantly larger decrease in local angel financing, entrepreneurial activity, innovation output, employment, and sales. I find that small business loans and second-lien mortgages became entrepreneurs’ partial substitutes for angel investment. My cost-benefit analysis suggests that the costs of protecting angel investors through the 2011 regulation change outweigh its benefits.
In the third chapter, which is co-authored with Thomas Chemmanur and Harshit Rajaiya, we address three important research questions by using a large sample of angel and venture capital (VC) financing data from the Crunchbase and VentureXpert databases and private firm data from the NETS database. First, we analyze the relative extent of value addition by angels versus VCs to startup firms. We show that startups financed by angels rather than VCs are associated with a lower likelihood of successful exit (IPO or acquisition), lower sales and employment growth, lower quantity and quality of innovation, and lower net inflow of high-quality inventors. We disentangle selection and monitoring effects using instrumental variable (IV) and switching regression analyses and show that our baseline results are causal. Second, we investigate the complementarity versus substitution relationship between angel and VC financing. We find that a firm that received a larger fraction of VC or angel financing in the first financing round is likely to receive a larger fraction of the same type of financing in a subsequent round; however, when we include other non-VC financing sources such as accelerators and government grants into the analysis, a firm that received angel (rather than other non-VC) financing in the first round is also more likely to receive VC financing in a subsequent round. Third, we analyze how the financing sequence (order of investments by angels and VCs across rounds) of startup firms is related to their successful exit probability. We find that firms that received primarily VC financing in the first round and continued to receive VC financing in subsequent rounds (VC-VC) or those that received primarily angel financing in the first round and received VC financing in subsequent rounds (Angel-VC) have a higher chance of successful exit compared to those with other financing sequences (VC-Angel or Angel-Angel).Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Carroll School of Management.Discipline: Finance
Prioritized memory consolidation over sleep: Do psychological and physiological markers at encoding set the stage?
Get PDFThesis advisor: Elizabeth A. KensingerEmotion enhances memory longevity and vividness. Perceiving an experience as emotional, as well as the autonomic and functional brain responses involved in initially encoding an emotional experience, have been theorized to “tag” these memories. Tagged memories may then be prioritized for consolidation during sleep. However, direct evidence supporting this theory is sparse. The aim of the present study was to determine which encoding-related indicators of memory tagging interact with post-encoding sleep oscillations to promote emotional memory retention and vividness. To test this, participants incidentally encoded positive, neutral and negative multisensory stimuli during 3T fMRI scanning with concurrent heart rate monitoring. Participants provided emotional intensity ratings after each stimulus presentation. Following a 120-min post-encoding nap opportunity recorded with polysomnography, participants completed a surprise memory test. Memory for emotional and neutral stimuli was equivalent, though emotional stimuli tended to be remembered more vividly. Perceived emotional intensity, but not heart rate deceleration (HRD) magnitude or functional brain activity, was diagnostic of later successful retrieval of emotional, but not neutral stimuli. Higher REM sleep theta power during the nap was associated with a greater emotional intensity (EI) subsequent memory effect (i.e., higher EI for later remembered compared to forgotten stimuli) for positive stimuli, which were also remembered more vividly. Higher NREM spindle density was associated with a greater EI subsequent memory effect for neutral stimuli and lesser EI subsequent memory effect for negative stimuli. Lastly, higher numbers of NREM spindle-slow oscillation coupling events predicted a negative relationship between perceived emotional intensity at encoding and memory vividness for negative stimuli. Taken together, the present findings suggest that subjective, rather than objective, encoding-related arousal responses acted as emotion “tags”. How subjective arousal impacted later memory varied as a function of the memory’s emotion category and REM and NREM-specific oscillations. Future work is needed to clarify the underlying mechanisms for these observed effects.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Psychology
Buried Under Interpretation: George Eliot's Early Heroines
Get PDFThesis advisor: Maia McAleaveyThis thesis examines the layers of interpretation that encase the female characters of George Eliot’s early fiction, and work through the seemingly contradictory ways in which Eliot intends for their status as created objects to be understood. Chapter 1 focuses on Caterina Sarti, Dinah Morris and Hetty Sorrel, and their depiction as both artists and art objects. Chapter 2 examines Maggie Tulliver and the way being a controlled object is embedded into her character, despite the appearance of freedom. What is puzzling about Eliot’s portrayal of these characters is that it is never clear how their attempts to be objects are meant to be understood. Eliot’s characterization of these young women is best understood in light of the association between becoming an object and “coming of age” as an adult woman. She sees no escape from this association, so these characters must be presented through layers of interpretation and objectification.Thesis (BA) — Boston College, 2022.Submitted to: Boston College. College of Arts and Sciences.Discipline: Departmental Honors.Discipline: English
An Intra-National Borderland: Regional Conflicts & Affinities Across the Austro-Bavarian Border, 1918-1955
No full textThesis advisor: Devin O. PendasThis dissertation studies the cooperation and competition amongst various right-wing paramilitaries in the southeastern portions of German-speaking Europe. My work overturns stereotypical, teleological narratives that presume any far-fight German extremism inherently meant “the rise of Nazism.” Instead, I reveal a complex mosaic of far-right paramilitary men, whose allegiances to and rivalries with each other oscillated with shifting situational contexts across one of the most contested and chaotic borders in interwar Europe. Consequently, my research results open new possibilities for conceptualizing volatile twentieth-century borderlands as stemming not just from international conflicts but also from intra-national infighting. Paramilitary men on both sides of the Austro-Bavarian border considered themselves German, but they conceived of their “Germanness” in very specific terms: southeastern, Catholic, and Alpine in contrast to the northern, Protestant, and Prussian variant of Germandom. How did right-wing groups blend greater German nationalism with their southeastern German regionalism? The hybridization of these two loyalties created an intoxicating affective brew that brought together right-wing agents on both sides of this border in fraternal solidarity but also instigated fratricidal violence, all as these German groups sought to settle the question of what it meant to be German. National identities founded on southeastern regional impulses thus formed a constitutive contradiction of greater German nationalism. The intersectionality of regionalism and nationalism generated internecine right-wing violence, as these groups disagreed over how to implement disparate versions of unification.
The result was twenty years of street brawls, assassinations, terror, Putsch attempts, mobilizations, and transborder smuggling of munitions, troops, and funds. This region was thus a paragon of borderlands conflict. The crux was that it was an intra-national borderland: to these activists, national union should have been so simple, making it all the more frustrating when it eluded them. The assumed common nationality meant any perceived dissident was not simply a political opponent but something far worse: a traitor. Paradoxically, the supposedly “agreed-upon” national identity exacerbated borderland chaos and violence. Historians of Eastern and Central Europe have falsely conflated borderlands with spaces between nations in which multi-national populations struggle among each other for hegemony. My work overturns such assumptions by offering the first analysis of European borderlands violence stemming from a perceived communal nationality. This project thus serves as a needed corrective to the scholarship, offering a richly informed regional analysis with significant interventions in the broader fields of borderlands and right-wing extremism.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: History
What Counts as Family Engagement in Schools?: Raced, Classed, and Linguicized Relations Between Families and a Two-Way Dual Language Bilingual Program
No full textThesis advisor: C. Patrick ProctorDominant conceptualizations for family-school relations across U.S. educational research, policy, and practice continue to privilege the behaviors, experiences, and practices of white, upper- and middle-class families, while failing to address the race and class power-relations that permeate educational institutions and their neighborhoods. In the field of bilingual education, there is an emergent body of research that examines issues of language, race, and class within the experiences of families in two-way dual language bilingual education, where children from multiple racial, cultural, and economic groups are educated together with the goals of bilingualism and biliteracy. However, this scholarship has not related the experiences and relations in bilingual programs to the broader issue regarding the dominant and deficit discourse of family-school relations in the U.S. In response, this dissertation situates families’ experiences in a two-way dual language bilingual program within the broader ideological, political, and historical dimensions of U.S. family-school relations. A theoretical orientation informed by Critical Race Theory, Critical Poststructuralist Sociolinguistics, and Feminist Poststructuralist frameworks was used to highlight how racialized positionalities of families in schools reverberate beyond individuals’ identity construction, connecting to discourses about families at other societal scales. This study utilized participant observations, semi-structured interviews, and artifact generation. Data was analyzed using discursive and textual analytical approaches. Findings include (a) an investigation of how the legal and institutional contexts related to family-bilingual school relations contribute to the racialization of people and their languaging; (b) an analysis of how raciolinguistic ideologies are deployed to naturalize the designation of linguistic and ethnoracial labels upon families; and (c) a generation of portraits highlighting how families ruptured deficit positionings by reporting on systems of oppression, their dynamic language practices, and their expansive relations across groups of people, places, and temporal scales. Ultimately, this dissertation argues that despite individual efforts of stakeholders in bilingual programs to foster the wellbeing and development of families, the racist and classist foundations of schooling will ensure the reification of oppressive educational experiences for multiply minoritized families. At the same time, these families will continue to find ways to survive, resist their subjugation, and reimagine more liberatory worlds.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Lynch School of Education.Discipline: Teacher Education, Special Education, Curriculum and Instruction
Accounting Standards Updates, Investments in Accounting Information Systems, and Firms’ Internal Information Environments:
Get PDFThesis advisor: Amy HuttonWhile the implementation of new accounting standards requires significant firm resources, the literature is largely silent on how firms allocate resources to comply with new accounting standards. I investigate whether firms make information systems (IS) investments to comply because IS are the primary means through which firms’ economic activities are captured, aggregated, and summarized for managerial decision-making. I use a requirement that firms disclose factors that materially affect their internal controls to identify IS investments. I find that—despite the large direct and indirect costs of IS investments and alternatives to comply with GAAP changes—new accounting standards lead to significant IS investments for the firms most affected by the GAAP changes. Moreover, the IS investments improve firms’ internal information environments. The results suggest that the IS investments and IIE improvements extend beyond the scope of the GAAP changes.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Carroll School of Management.Discipline: Accounting
To Teach Our Daughters Their Importance in the World: An Analysis of Jacqueline Woodson’s Middle Grades and Young Adult Literature with Black Girl Protagonists
No full textThesis advisor: Patrick ProctorJacqueline Woodson has been writing for children, young adults, and adults for thirty-two years. She has won numerous national and international awards for her writing for young people. Her books grapple with topics like teen pregnancy and incarceration with sensitivity and compassion. Her young adult literature deserves closer examination for their potential as instructional tools for English teachers. The purpose of this dissertation was to explore the history of African American children’s literature, the nature of Woodson’s contribution to contemporary African American young adult literature, and to make direct links to teaching Woodson’s YA literature in contemporary high school English classrooms. To these ends, this dissertation has three analytic chapters. In Chapter One, I present a history of African American children’s literature to situate Jacqueline Woodson’s work in the tradition of African Americans writing culturally and racially affirming text for Black children. The chapter highlights Black women who were actively writing during the Harlem Renaissance, the Chicago Black Renaissance, and the Black Arts Movement, and whose work undergirds much of Jacqueline Woodson’s success. Specifically, I highlight the works of Jessie Fauset, Effie Lee Newsome, Gwendolyn Brooks, June Jordan, and Virginia Hamilton.
In Chapter Two, I analyze a set of young adult literature written by Jacqueline Woodson. Specifically, I analyzed 10 of Woodson’s YA texts with Black girl protagonists through the lenses of Black Feminist Thought, Black Queer Theory, and Black English. I identified three themes that ran through Woodson’s work and were related to the theoretical lenses: (1) claiming and naming oneself, (2) finding community and belonging, and (3) remembering.
Finally, in Chapter Three I provide four sample unit plans derived from the analyses in Chapters 1 and 2. The first unit plan uses Woodson’s text as a mentor text for student self-reflection. The second unit pairs Woodson’s text with a text written by Virginia Hamilton to understand the impacts of coal mining. The third unit uses Black Feminist Thought to analyze and compare one of Woodson’s texts with an adult text written by a Black woman. In the final unit plan, students study Woodson’s memoir in verse to understand how authors use their own lived experiences to create stories.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Lynch School of Education.Discipline: Teacher Education, Special Education, Curriculum and Instruction
Molecular Beam Epitaxy Synthesis and Nanoscale Characterization of Topological Insulator Thin Films and Their Interface With High-temperature Superconductors:
Get PDFThesis advisor: Ilija ZeljkovicThe discovery of topological phases has ushered in an era of new materials with exotic electronicproperties; one particular area of excitement is realizing and studying topologically superconducting
systems. These topological superconductors are theorized to host exotic excitations that can be applied towards making fault tolerant quantum computations. One way to achieve this is depositing thin films of topological insulators onto superconducting substrates. Molecular beam epitaxy offers precise control for fabricating thin film heterostructures down to the single layer limits. In this thesis I will present my work on the synthesis of thin film topological insulators grown epitaxially on both an iron based superconductor FeT e0.55Se0.45 as well as a cuprate superconductor Bi2Sr2CaCu2Ox+8. Additionally I will cover the scanning tunneling microscopy/spectroscopy characterization of the emergent phenomena on the surface as well as at the interface of these heterostructures. This work presents a viable platform for exploring the emergence of superconductivity in topologically insulating materials, as well as demonstrates the importance of a clean interface.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Physics
TheLove of Truth & The Truth of Love: Retrieving Saints Augustine & Thomas Aquinas on the Relationship of Understanding & Love
No full textThesis advisor: Frederick G. LawrenceJohannine literature explains the meaning of Jesus of Nazareth and our relationship with God in terms of logos and agape: the Logos is Theos (Jn 1) and Theos is Agape (1Jn 4). The goal of this dissertation is to relate these two, understanding and love, to develop a master analogy for the revelation of God to human beings. This is elaborated through close reading and commentary on classic texts by two Doctors of the Church, Augustine and Thomas Aquinas, in an attempt to reconcile voluntarist and intellectualist approaches to the question of God by showing how the act of understanding is analogous with the act of love. Augustine would integrate his understanding of Scripture and philosophy into his theory of the inner word (verbum mentis) as the image of the Triune God. This consummate theological achievement is also a meta-analysis of personal communication by a master of the art of rhetoric, defined as “the good man, skilled in speaking” (vir bonus, dicendi peritus) by Cato the Elder in Quintilian’s Institutio Oratoria. The Bishop of Hippo affirms the words of a wise person as the ideal of communication, as perfected in the life of the Christian evangelist. A systematic exegesis of Augustine’s personal, rhetorical, and theological synthesis, the first part of this dissertation is a study of several key texts to explore how the Doctor of Grace relates love with understanding, the words of Scripture with those of the philosophers.
Thomas Aquinas develops Augustine’s insights in the theological system of his Summa theologiae, expanding the theory of the inner word into a theoretical synthesis uniting reason and
faith, scientia and sapientia, which the Doctor of Grace was not able to achieve. The second part of the dissertation analyzes and complements the reading of Augustine in the first part by testing it in dialogue with Aquinas’ treatment of the same themes—understanding and love—in the First and Second Parts of the Summa as representative of his mature thought.
The study of these two figures is intended as an attempt to apply Lonergan’s Method in Theology. By developing the relationship between knowing the truth and loving it, this project expands upon his efforts to sublate the linguistic phenomenology of Heidegger’s hermeneutic revolution within a theological system. Lonergan formulates his own hermeneutic as four levels of knowing: experiencing, understanding, judging, deciding. Having his insight on the centrality of love late in life, however, he would leave his interpreters with the question of how to integrate knowing with loving. The exigencies of publishing Method would also mean leaving the problem of communication as a challenge for his successors. This dissertation seeks to propose a solution with the retrieval of Augustine’s hermeneutic of caritas as a model for communicating Christian self-appropriation through a phenomenology of how we realize the logos.
We understand the meaning of a whole by recognizing the order in which all its parts fit together. In this way, judgment operates analogically as a determination of the fittingness of a logical proportion. And so, as Logos, God is the order into which all things fit together, revealed to us as a complementary pattern, which is expressed through analogy. In the Catholic tradition, this pattern of grace is consummated by receiving bread and wine sacramentally, and recognizing in them the essence of our relationship with God as well as one another, as we realize this loving relationship as the form of all our acts.Thesis (PhD) — Boston College, 2022.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Theology