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Correlated electronic structure theory for interfacial chemistry and excited states of extended systems
No full textI begin by discussing the fundamentals of wave function theory, focusing on Hartree–Fock as the foundation of most quantum chemistry methods. I then provide details on basis sets and the formalism of second quantization, followed by an overview of configuration interaction. Building on this, I present the formalism of coupled-cluster theory and equation-of-motion coupled-cluster theory, and finally, I describe how these methods can be extended to treat periodic systems.
In Chapter 2, I explore valence excitations of semiconductors and insulators with correlated wave function theory. I calculate the band gaps of 12 inorganic semiconductors and insulators composed of first- through third-row elements using periodic equation-of-motion coupled-cluster theory with single and double excitations (EOM-CCSD) and atom-centered triple-zeta basis sets with up to 64 k-points. I analyze convergence with respect to orbital and k-point sampling, applying composite corrections and extrapolations to obtain final values. At the end of this chapter, I discover the performance of EOM-CCSD relative to workhorse methods in the community and how it fares against approximate excited state wave function methods.
Chapter 3, I report core binding energies for K-edge and L-edge transitions in simple semiconducting and insulating solids using periodic EOM-CCSD. My all-electron calculations employ triple-zeta basis sets with core correlation and Brillouin zone sampling of up to 4 x 4 x 4 k-points. Final values are obtained through composite corrections and extrapolation to the thermodynamic limit, yielding errors comparable to the accuracy of CCSD for molecular systems. The low-scaling approximation to EOM-CCSD achieves slightly reduced accuracy, but at significantly lower computational cost.
In the final chapter, I apply density functional theory and coupled cluster theory to investigate electrolyte decomposition on lithium metal surfaces, a key phenomenon in energy materials science. To enable the use of mature molecular quantum chemistry methods, I segment the adsorbed molecule–lithium system into molecular clusters. I find that even small, computationally tractable clusters, when combined with composite corrections from basis set and method refinements, can serve as an effective tool for identifying high-performing functionals and for parameterizing machine-learned force fields
The Early Buddhist Art of Phaṇigiri: Innovation and Ideology in the Riverine Deccan, ca. 1st-4th centuries CE
No full textThe early Buddhist site of Phaṇigiri, located on a hill in the ancient Āndhradeśa region of the eastern Deccan, and bounded by the Kriṣna and Godāvarī river systems, has yielded a fragmentary and limitedly understood architectural and sculptural corpus from at least the first to the fourth centuries CE. The early evolution of the site coincides with the proliferation of stone construction in Deccan or south India, and predates its Hindu monuments and Islamic structures by several centuries. The site’s later development corresponds to the decline of active construction of ancient Buddhist complexes in Āndhradeśa, and the rise of Brahmanism in the region, the scholarship on which is limited by the “Deccan gap,” or absence of contemporaneous textual sources.
In five chapters, ṇ studies the architecture, sculpture, coins, and inscriptions at the site alongside a presentation of new photographs and maps. It shows that the monastic program of Phaṇigiri, bookended by a landscape dotted with megaliths and a memorial stone, was transformed by a long history of donation for construction, expansion, and repair. The vitality of the early Buddhist site was reflected in narrative reliefs and free-standing sculpture which drew upon, and extended beyond, canonical artistic traditions. The material basis of Phaṇigiri’s architectural program and sculptural corpus was a system of patronage that was non-royal in nature, reflecting local ideologies and broader cross-cultural concerns, thereby challenging the applicability of dynastic labels, such as “Ikṣvāku,” typically used to describe the site. This distinctive art was mobilized by an active network of production—comprising itinerant supervisors and sculptors—along the interlacing rivers of the Deccan as they flowed into the eastern Indian Ocean. Through a close reading of the art on site despite, and through, its fragmentation, The Early Buddhist Art of Phaṇigiri highlights the relationship between the early Buddhist site and stonework to establish that Phaṇigiri was a dynamic local idiom of the Deccan school of early Buddhist art in premodern South Asia
A Blank Canvas: Natural Disaster Relief and the Climate Gentrification of Black Neighborhoods
No full textThis thesis explores the intersection of climate gentrification, disaster relief, and urban renewal practices in Black communities across the United States. Beginning with a historical analysis of the ways public and private interest groups have systematically disenfranchised Black neighborhoods through the disinvestment of infrastructure and racialized zoning, these practices became commonplace across the country with the entrapment of Black residents in neighborhoods located near flood zones, toxic waste disposal plants, and contaminated with poor air quality. Using three (3) case studies including New Orleans and Hurricane Katrina (2005), Brooklyn and Hurricane Sandy (2012), and Houston and Hurricane Harvey (2017), this research examines how natural disasters have served as catalysts for urban renewal policies that often exclude or displace long-term Black residents. While federal disaster relief is intended to promote recovery and resilience, in practice funds are frequently distributed in ways that prioritize large-scale redevelopment and private investment over equitable rebuilding for vulnerable communities. This study interrogates the structural and historical forces that shape such outcomes, including redlining, racialized zoning practices, benign neglect strategies, and the longstanding devaluation of Black neighborhoods. Employing a mixed-methods approach, the research incorporates census and economic data analysis alongside qualitative interviews with residents, community leaders and stakeholders, and government officials. The findings aim to illuminate the mechanisms through which disaster capitalism accelerates gentrification and deepens racial inequities, while also considering community-led resilience strategies that offer more just and sustainable alternatives. Ultimately, this thesis seeks to answer whether disaster relief and urban renewal planning can be reimagined to foster equity, sustainability, and inclusion in Black communities most at risk of the impacts of climate change.
Keywords: climate gentrification, disaster capitalism, urban renewal, emergency management, community developmen
Which Community College Awards Are Likely to Prepare Students for Post-Completion Success?
No full textThis report uses IPEDS and College Scorecard data to classify the credentials awarded by community colleges in 2022-23 and to assess which credentials are and are not likely to enable students to secure a living-wage job or transfer efficiently in a major
Discussion Guide for More Essential Than Ever: Community College Pathways to Educational and Career Success
No full textThis discussion guide for More Essential Than Ever is designed to help community college faculty, staff, and administrators discuss ideas presented in the book and consider which might be most helpful for improving student success at their institutions
Towards Operational UAS-Based Landmine Detection: Vegetation, Validation, and Geophysical Application
No full textThis dissertation addresses the decades old humanitarian crisis of landmine and unexploded ordnance contamination by applying modern advances in unmanned-aerial vehicles (UAV), geophysical sensors, and computer vision.
Chapter 1 focuses on quantifying the effect of vegetation on detecting surface ordnance. Potentially the most important consideration for UAV-based object detection in the natural environment is vegetation height and foliar cover, which can visually obscure the items a machine learning model is trained to detect. Hence, the accuracy of aerial detection of objects such as surface landmines and UXO is highly dependent on the height and density of vegetation in a given area. In this study, we develop a model derived from an area's digital surface model that estimates the detection accuracy (recall) of an object detection model as a function of occlusion due to vegetation coverage. This methodology has significant implications for determining the optimal location and time of year for UAV-based object detection tasks and quantifying the uncertainty of deep learning object detection models in the natural environment.
Chapter 2 develops the physical infrastructure required to advance landmine detection research by designing and creating a comprehensive and realistic seeded minefield with 143 diverse types of explosive ordnance. The field is designed to accelerate research in the field of humanitarian mine action by providing an accessible, diverse testing area located at OSU’s Center for Fire and Explosives, Forensic Investigation, Training and Research range in Pawnee, Oklahoma to address the lack of realistic accessible test sites for mine action researchers.
Chapter 3 introduces the anomaly (A), identifiable anomaly (I), and unique identifiable anomaly (U) AIU Index, which is an object detection disambiguation framework, that enables the comparison of different geophysical and imagery-based detection modalities while taking into account the detection fidelity and corresponding false positive rate. The AIU index prescribes essential context for false-positive-sensitive or resolution-poor object detection tasks such as landmine detection with applications in modality comparison, machine learning, and remote sensing data acquisition.
Finally, Chapter 4 builds on the efforts of Chapters 1, 2, and 3 by comparing UAV-based geophysical techniques for landmine detection with the AIU Index on the seeded minefield. This chapter encompassed the largest ever multi-modal remote sensing datasets on a seeded minefield and assessment on the state-of-art UAV-based explosive ordnance detection methods. Across 34 distinct datasets and 143 explosive ordnance items, we systematically assess state-of-the-art UAV-based remote sensing methods spanning visual, thermal, multispectral, hyperspectral, LiDAR, synthetic aperture radar, magnetometry, and ground-penetrating radar (GPR), alongside handheld and cart-based electromagnetic induction (EMI) metal detection, spectroscopy, and GPR. In conclusion, we found UAV-based RGB imagery was the most cost effective, scalable, and highest accuracy method for detecting surface targets, and the traditional handheld EMI-based metal detector was the most effective way to detect subsurface targets. This work aims to advance UAV-based landmine detection toward achieving tangible humanitarian impact in conflict and post-conflict regions
Evaluating a Community-Based Intervention to Advance Food Equity and Climate Resilience in the South Bronx: Findings from the LEAF Program
No full textAccess to ecologically grown, nutritious food remains limited in low-income U.S. communities due to cost, structural inequities, and the dominance of industrial food systems. Stone Barns Center’s Leading an Ecological and Accessible Food System (LEAF) program—developed through a community-based participatory partnership in the South Bronx—aims to address these challenges through biweekly distributions of regeneratively grown produce, seasonal gardening kits, and culturally responsive nutrition education. This study presents findings from the first two years (2023 and 2024) of a multi-timepoint repeated cross-sectional evaluation using six household-level surveys (n = 79–80 families per round). The surveys captured changes in fruit and vegetable consumption, gardening comfort, emotional well-being, participation in SNAP and WIC programs, food purchasing behaviors, and unmet needs. Statistically significant (p < 0.05) improvements were observed across key outcomes: mean fruit and vegetable intake increased from 3.8 to 4.5 (1–5 scale), comfort with growing food increased from 3.1 to 4.6, emotional response to gardening from 4.1 to 4.6. SNAP participation increased from 15% (12 of 79 households) to 33% (26 of 79 households), and purchasing shifted toward local access points. Notably, 99% (79 of 80 households) of Year 1 families returned for Year 2, reflecting strong engagement and trust. These results highlight the potential of integrated, community-partnered, and climate-aligned interventions to advance health equity, ecological literacy, and food justice. The LEAF program offers a replicable model that may support pathways towards more sustainable and community-aligned food systems in other under-resourced settings.
Keywords: food access; nutrition equity; urban agriculture; regenerative agriculture; community-based participatory research; SNAP and WIC; home gardening; health disparities; sustainable food systems; climate resilienc
Cloth-gestures on Roman sarcophagi
No full textThis dissertation sheds light on manipulations of drapery to express emotions and moral dispositions in Greek and Roman art. Using Roman sarcophagi reliefs as the main database but also reaching beyond it to other earlier or contemporary visual media, including rhetorical performances and theatre, it does so by identifying a series of recurring “cloth-gestures”, an art historical term coined to detect and analyze recurring gestures in art and life involving the manipulation of drapery for the nonverbal communication of a variety of signals.
Within the wide array of uses of drapery in ancient art, it identifies two main tendencies: one is to manipulate veiling patterns to amplify emotions and to extend the expressive range of the body, especially through windswept drapery motifs (part I), where the drapery is shown waving to suggest and elicit pathos, from eros to panic to elation. This tendency, starting in Greek art, and becoming more pronounced and codified in Roman art, crystalizes into two ubiquitous “cloth-gestures” : the semi-circular swollen veil known as velificatio, signaling an heightened emotional state most often associated with women (chapter 1), and the fluttering cape of heroes signaling a rush of courage strongly characterized as masculine, akin to concepts of virtus (chapter 2).
In part II, I explore the almost opposite tendency presented by the ancient evidence: to manipulate drapery to inhibit the expressive range of the body, communicating ideas of emotional restraint. My case-study (chapter 3) for this part is the cloth-gesture of veiling the face and body to communicate aidos in Greek art, and in Roman art, pudicitia, sexual restraint and marital faithfulness–a gesture strongly coded as feminine. The use of the same cloth-gesture as a “pathos formula” to communicate extreme forms of grief, however, challenges rigid codification, as well as the clear distinction between part I and part II, revealing that the two tendencies are manifestations of the same ancient strategy of veiling emotions, rather than displaying them more directly (for instance, on the face).
An art historical study of ancient emotions and dispositions on the folds of their drapery reveals to what extent these concepts were gendered in antiquity, as well as a blurry zone in ancient categorizations between what we distinguish as psychological and ethical phenomena. After my attempt to pin down the meaning of each cloth-gesture, I conclude that what marks out cloth-gestures from bodily gestures is their wider semantic openness and even volatility, explaining perhaps why they become such a privileged resource for the communication of emotions and dispositions, intrinsically ambivalent and shifty phenomena
Dolly’s Laugh: a meditation on recorded excess
No full textThis creative response is an attempt to understand our long-standing obsession with the moments that shouldn’t be in song recordings but somehow remain. Written while we were physically apart over the course of a few months, our dialogue responds to a desire to understand whether there is any meaning in these obsessions, whether they can teach us about sound and the musicians that produce them. We want to call attention to what is usually discarded – what happens before, after or in-between, what happens on top of – moments in excess of the track which break the performative bargain and reveal the multiple possibilities always contained within performance. The piece is accompanied by a soundpiece putting some of the recorded moments mentioned in dialogue with each other.
Notes on Contributors
Ruari Paterson-Achenbach is an interdisciplinary artist and researcher, currently undertaking their PhD in Music at the University of Cambridge. Their work thinks about sound and performance as vehicles for memory, resistance and temporal antagonism. Through a critical engagement with ‘Outsider Music,’ their PhD uncovers radical potential for creativity within and through non-normative social life. More broadly, their research interests include queer temporality, critical listening, and creative anarchism. Ruari was also a ‘New Creative’ and has produced works with and for the Institute of Contemporary Arts in London, the BBC and NTS Radio.
Sophie Marie Niang is a black feminist researcher from Paris, working at the intersection of cultural studies, black studies, and queer theory. She is currently a Junior Research Fellow in European Cultural Studies at Magdalene College, University of Cambridge. Her first book project explores black refusal and worldmaking in contemporary France, through a focus on rap, black women’s self narratives in film and literature, afrofeminist performance, and literary fiction. Her work is published in Sociology Compass, Feminist Review, and Modern & Contemporary France
Discontinuous Galerkin Methods for Nonlinear and Nonlocal Wave Equations
No full textThis dissertation develops and analyzes discontinuous Galerkin (DG) methods for two wave propagation problems: the nonlinear Schrodinger equation with wave operator (NLSW) and the nonlocal wave equation (NLW). These models arise in diverse physical and engineering contexts ranging from plasma physics to peridynamic solid mechanics, and pose significant numerical challenges due to their dispersive, nonlinear, and nonlocal behavior. Efficient numerical algorithms for these problems are essential for accurately simulating phenomena such as soliton dynamics and long-range interactions.
For the NLSW model, we propose an energy-based DG formulation that preserves discrete energy properties and admits optimal convergence in the L2 norm. A key component of the method is the introduction of an auxiliary variable along with the careful design of mesh-independent numerical fluxes. We establish rigorous stability and error estimates for the semi-discrete scheme. To handle the time dimension, we employ a strong-stability-preserving Runge–Kutta (SSPRK) scheme, ensuring robust and accurate temporal integration. The method is validated through extensive numerical simulations in one and two spatial dimensions.
For the NLW model, we construct and analyze a DG method that accommodates spatial nonlocality and is capable of capturing the asymptotic transition to local models. We discretize in time via a Crank–Nicolson scheme, combining second-order accuracy with favorable stability properties. The method preserves energy at the fully-discrete level and exhibits optimal convergence rates for a broad class of nonlocal kernels. We further establish asymptotic compatibility, ensuring that the scheme recovers the classical wave equation in the vanishing-horizon limit.
In addition to standard numerical analysis of the schemes, we demonstrate, through extensive numerical simulations, the accuracy and effectiveness of the proposed methods. This dissertation offers some new insights on developing advanced DG-type methods for nonlinear and nonlocal wave equations, especially in second order form