Graduate Theses and Dissertations

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Development of New Catalysts and Concepts for Enantioselective Synthesis of Amines and Alcohols
Chapter 1: Ag-Catalyzed Enantioselective Vinylogous Mannich Reactions of Ketoimines Few catalytic methods have been reported for the enantioselective synthesis of N-substituted quaternary carbon stereogenic centers, typically the low reactivity of the electrophilic partner cannot be overcome. Herein, a silver-based catalyst is described which promotes highly site-, diastereo-, and enantioselective additions of siloxyfurans to ansidine-derived ketoimino esters. Mechanistic investigations, undertaken to elucidate the nature of the active silver-phosphine complex, supported the proposed origin for the anti-selective Mannich-type additions. Chapter 2: New Catalysts for the Enantioselective Cu-Catalyzed Additions of Allyl Groups to Phosphinoylaldimines The deficiencies in modern organic synthesis regarding the preparation of chiral molecules bearing amines, despite their incredible significance, are addressed. The development of a new method and catalyst for the preparation of enantiomerically enriched allyl-substituted alpha-chiral amines is described. Copper based catalysts bearing chiral C1-symmetric N-heterocyclic carbenes promote reactions between diphenylphosphinoyl aldimines and allyl boronic acid pinacol ester affording the homoallylic amines with high levels of efficiency and selectivity. Furthermore, the mechanistic rationale describing the selectivity patterns of the designed catalysts is analyzed. Chapter 3: NHC-Cu-Catalyzed Enantioselective Propargyl Group Additions to Phosphinoylaldimines The copper complex of a chiral N-heterocyclic carbene is found to be uniquely effective at promoting highly selective reactions of a commercially available allenylboron reagent and diphenylphosphinoyl aldimines. The enantiomerically enriched homopropargylic amines are exclusively afforded within an hour in the presence of as low as 0.25 mol % catalyst. The utility of the method is further demonstrated through the elaboration of the appended alkyne to difficult-to-access functionalities, highlighted by the synthesis of a key fragment for the preparation of the aza-epothilones, macrocyclic lactams which exhibit acute cytotoxicity. Chapter 4: Metal-Free Catalysts for Enantioselective Synthesis of Allenic Carbinols A metal-free catalyst, unique in structure and mechanism, is developed to address the remaining deficiencies in allyl addition chemistry, an area dominated by metal catalysis. The key organizational and enabling feature of the catalyst is a proton, a simple point charge which affects the facility of the C-C bond formation through electrostatic interactions. The unique alpha-selectivity delivered by the boron-based catalyst, a product of a catalytic cycle characterized by two gamma-selective allyl transfer processes, allows for the unprecedented synthesis of enantiopure allenyl-substituted tertiary alcohols. Moreover, the described transfomations can be performed in a matter of minutes with ˂0.5 mol % catalyst.
"Be angry, but do not sin"
From its earliest days, Christianity has debated about when and how force can be used to repel harm without incurring sin. Although moderation and restriction have often been advocated both on a personal and on a social level, strict passivity has rarely been the proposed solution in mainstream Christianity when individuals or nations are confronted with harm. The Just War tradition, in its many variations, was born precisely out of this desire to make sense of how force can be used in a Christian way. And it soon became the prevalent theory throughout Christianity to address issues of violence, war, and force in general. What this thesis intends to argue is that Just War theory, despite all its pervasiveness, is flawed in some crucial aspects when scrutinized from a Christian viewpoint. Three such aspects seem to be especially relevant: Just War tradition is not grounded enough in Scripture; its jus ad bellum and jus in bello criteria do not protect in a satisfactory way the innocent who face harm; and it is a theory that is only reactive to force being imposed upon others. Because of these three flaws, it will be claimed that in the process of giving its support to Just War theory Christianity has largely forgotten an older, broader tradition. The “be angry, but do not sin” tradition has Scriptural and philosophical roots that, when combined, can bring a Christian virtue ethics to a much better understanding of when and how forceful intervention in the social sphere is required. At the very least, this anger tradition does not fall prey to the three criticisms that are addressed towards Just War – and that seems to make it especially valuable. Righteous anger, then, and not Just War, should be what guides Christianity in its thinking about how and when force can be used without incurring sin. That is the contention of this thesis.
"Beyond the screen"
As an emergent form of internationalization that incorporates the use of digital technology, virtual exchange offers students the possibility to transcend national borders and connect with other students entirely within a virtual learning environment. Participants in virtual exchange mediate between the physical and virtual worlds, and a sense of place allows them to connect with peers, actively engage with their environment, and achieve learning outcomes. Despite a growing interest in virtual exchange in higher education, however, there is limited research on how students navigate their online learning environment and develop a sense of place. This thesis addresses this gap by exploring how students construct and experience a sense of place while participating in virtual exchange. Focus group interviews were conducted with 29 students participating in virtual exchange through the non-profit provider, Soliya. Using grounded theory, a number of emergent themes were explored, revealing how students understood and situated themselves within both their physical and virtual spaces before, during, and after their virtual exchange. The findings of this study suggest that sense of place is impacted by the environment as well as both individual and communal identity. The results of this study will provide higher education institutions and virtual exchange providers with a better understanding of the construct of sense of place within virtual learning environments and, consequently, how to foster a strong sense of place among virtual exchange participants.
"Crowded Churches and Empty Stomachs"
The title of this essay is deliberately provocative. It aims at drawing attention on the reality of Christian churches full everyday – not only on sundays – with people who everyday die from hunger. In the Congo-Zaire. Behind the image of crowded churches, I see the complex reality of Christianity, and behind the image of empty stomachs, I have in view the complex reality of poverty, oppression, violence and death. It is paradoxical that those two realities grow together. This essay explores the sources of that paradox, going back to the first encounter of the people of the old Kongo Kingdom, and later on Congo-Zaire, with Christianity. It analyzes the relationships between Christianity and the poor throughout the history of the Congo-Zaire. It examines the message of salvation brought by Christianity and how it is related to the people’s conditions of life. The conclusion is tough, but unavoidable. First, Christianity during colonial times – which I call missionary Christianity – in the Congo-Zaire did not side with the poor. It served the interests of the powerful, to safeguard its own interests. It despised the way of life of the autochthonous and destroyed their identity. Second, Christianity today in the Congo-Zaire – which I call postindependence Christianity – struggles with the heritage of the colonial past, but it basically continues to function following the same model. We still live in the colonial settings. Therefore, this for me is the key to resolving the paradox. Following the insights of postcolonial theories, turn the page of colonial Christianity, move towards what I call a “postcolonial Christianity.” That postcolonial Christianity should be informed by the African way of life (hence re-appropriating the values of the autochthonous) and rooted in the preferential option for the poor, which is the main principle at the heart of liberation theology. There lies a great challenge: how to actualize that postcolonial Christianity in the Congo-Zaire?
"From 'the exclusion from' to 'the sharing of' God's Baraka"
Reconciliation is based on a change in the attitude of humans toward one another and toward God. Jacob returns to Canaan to obey an order of God and to fulfill his promise. His encounter with God upsets him. His deference to Esau shows a change of attitude that produces a reciprocal effect on his brother. By sharing his wealth, Jacob recognizes the goodness of God who has filled him, accompanied him on his return and touched Esau to welcome him. Esau, also beneficiary of God's generosity, knows how to forget the past and to show himself in favor of his brother. The two brothers are blessed, and they bless each other. This mutual blessing goes beyond the sharing of material wealth. The forgiveness granted and received constitutes a central piece where each protagonist feels lifted up: Jacob recovers his status of a brother (no longer a target to be destroyed), and Esau’s face reminds the loving face of God. And I think, this is the moment when reconciliation happens between the two brothers. The account of Genesis 32-33 provides us with the (historical) example of a process of reconciliation anchored in a spiritual vision, with the participation of God and human beings. These features of Jacob-Esau process of reconciliation can be built upon to foster reconciliation among the estranged individuals and groups in the Congolese and African context.
1,2-Oxaborines
Despite extensive research in B–N-containing aromatic systems (most notably 1,2-azaborines) for their potential use in biomedicine and materials science, development of their oxygen counterparts, 1,2-oxaborines, remains underdeveloped. Presented herein is a straightforward route to access 1,2-oxaborines via a ring-closing metathesis strategy. Attempts to utilize the 1,2-oxaborine as a 1,3-diene in the Diels–Alder cycloaddition for potential application as a 4C + 1O synthon are also presented. Lastly, investigations regarding the aromaticity of the B–O heterocycles is probed using computations and isothermal reaction calorimetry.
Ab Initio Theory of Thermal Spin-Lattice Disorder in Iron and Invar
Despite its deceptive simplicity and because of its scientific and technological importance, bcc Fe is still the subject of research and debate. We develop an ab initio theoretical framework and apply it to calculate temperature-dependent phonon modes and magnetic interaction parameters in bcc Fe. This framework incorporates realistic thermal disorder in a coupled spin-lattice system. Thermal spin-lattice coupling is found to significantly renormalize the phonon modes and magnetic interaction strength, resulting in significant temperature-dependencies. A method for treating magnetic systems of unknown entropy is developed and applied to calculate phonon modes and investigate the anomalous thermal expansion of the classical invar alloy, Fe0.65Ni0.35. Results over the temperature range 50K to room temperature are consistent with the observed low thermal expansion of this material. Excellent agreement with measured data is achieved for calculated phonon modes in both bcc Fe and the invar alloy.
Accounting Standards Updates, Investments in Accounting Information Systems, and Firms’ Internal Information Environments
While 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.
Addressing the Need for Recognition
Why should any society acknowledge and address recognition as a vital human need? This dissertation primarily sets out to offer a theological ethical response to this opportune and critical question. Fundamentally, it does not attempt to develop a new theory of recognition or, even, correct the existing ones. Rather, in agreement with the Aristotelian eudemonistic principle that the end of ethics is virtuous action and drawing on major theories of recognition, it highlights the necessity of acting virtuously in a manner that properly addresses the human need for due recognition. Its ultimate goal is to highlight the ethical significance of recognition as a vital human need. This goal is premised on the central thesis that all human beings need to be duly recognized and consistently treated as subjects with inherent dignity and fundamental rights; and, that failure to address the need for recognition leads to a catch-22 situation in human society. Therefore, it argues that doing a proper social ethics, especially Catholic Social Ethics, practically demands that we duly address the human need for recognition and explore how to integrate the habit of mutual recognition into the moral schemas of our societies so as to create a thriving culture of recognition – one that normalizes, prioritizes, and sustains mutual recognition as a common ground for negotiating the common good in modern multicultural and pluralistic societies.
Adolescent Girls’ Contributions to Community and Society
Youth contribution is important to the development of a healthy society (Lerner, Dowling et al., 2003; Schmid & Lopez, 2011). As youth develop on positive trajectories, they engage in higher rates of contribution to self, family, community, and civil society (Lerner, 2004). Many youth believe it is important to participate in contribution-oriented activities, but not many are involved in personally meaningful forms of contribution (Hershberg et al., 2014; Zeldin et al., 2013). In order to engage youth in contribution, and thereby increase the likelihood that they will continue to contribute into adulthood, it is important to understand the processes involved in contribution, the ways in which adolescents experience contribution, and how they conceptualize their role in giving back to the community. In the present research, I addressed the following questions: 1) How do adolescent girls experience contribution in their lives? (a) In which contribution-related activities are they involved? (b) What beliefs do they have about contribution? (2) How do adolescent girls direct their contribution goals or efforts? To whom do they contribute, or want to contribute? (3) What motivations are associated with contribution goals or efforts for adolescent girls? Through in-depth semi-structured qualitative interviews, I investigated adolescent contribution in nine adolescent girls in high school. This subsample of participants is drawn from the Connecting Adolescents’ Beliefs and Behaviors (CABB) Study (Lerner & Johnson, 2014), a longitudinal investigation of youth character development in adolescent students in the New England area. I analyzed the interviews using the Listening Guide (Gilligan, Spencer, Weinberg, & Bertsch, 2006), a method for analysis of qualitative texts. I derived many themes from these texts to address my research questions. Youth expressed a range of contribution experiences, including how they conceptualize what counts as making a contribution. Participants directed their contributions in accordance with their personal social identifications, their future career goals, and people seen as generally “less fortunate.” Youth expressed multiple intrinsic and extrinsic motivators for contributing and wanting to contribute in the future. Implications for future research, programming and policy will be discussed.

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Paul Ricoeur's Hermeneutic Detours and Distanciations bc-ir:101183 7,514
Multi-diagnostic Investigations of the Equatorial and Low-latitude Ionospheric Electrodynamics and Their Impacts on Space-based Technologies bc-ir:108001 5,317
Determination of Hydraulic Conductivities through Grain-Size Analysis bc-ir:106982 4,579
Montesquieu on the History and Geography of Political Liberty bc-ir:103616 4,499
Disciples and Discipleship in the Gospel of Mark bc-ir:101384 4,348
Stepping Off The Conveyor Belt bc-ir:104364 4,147
Saint Thomas Aquinas on the Death Penalty bc-ir:101201 3,933
Professional Development for Teaching in Higher Education bc-ir:104134 3,448
Psychologists' Experiences Working with Clients in Poverty bc-ir:103740 3,246
The Impact of Pension Policy on Older Adults' Life Satisfaction bc-ir:101752 3,127

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