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Control Data: American Power and the Global Assembly Line, 1957-1992
No full textThis dissertation provides a history of Control Data Corporation from the company’s founding in 1957 to its dissolution thirty-five years later with the end of the Cold War. The project argues that the company’s management, responding to changing US industrial policy in the mid-1960s, pioneered a defining feature of US political economy in the post-Cold War era—global assembly—as a form of Cold War governance. Control Data’s global assembly line exploded the Fordist self-contained, vertically-integrated factory and strategically placed the constituent phases of manufacturing—research and development (R&D), marketing, assembly, and subassembly—around the world. Geographically segregating “high”-value production from “low”-value assembly work allowed management to optimize the price of basic manufacturing and internalize research costs. Reorganizing business also reordered the structure of American political and social power at home and abroad.
In making these points, the dissertation takes the reader from the establishment of the company in 1957 through initial attempts to build manufacturing capacity before globalizing production. The analysis, from there, follows corporate leadership as they constructed the company’s global assembly line in the mid-1960s and 70s—tracing their journey through rural assembly works in the Upper Midwest, right-to-work-states, War on Poverty-era “poverty plants,” expanding industrial parks in East Asia, and even behind the Iron Curtain. The dissertation thereafter analyzes a failed attempt to export this business model to computer services in the 1980s. The narrative highlights how, at each step along the way, Control Data management targeted female workers, and, in doing so, transformed the social base of manufacturing at home and abroad in a way that challenges standard narratives of “deindustrialization” and “post-Fordism.” The analysis closes with a discussion of how global assembly lines of the 1960s and 70s persisted past Control Data’s own dissolution at the end of the Cold War and gave way to the “global value chains” of the 1990s-2010s.
The project draws on a wide source base and uses a range of qualitative and quantitative methods to tell this history. These materials include a plethora of corporate archival papers as well as government documents ranging from local business licenses to white papers, diplomatic cables, field reports, trade and labor statistics, and beyond. In addition to this written record, the dissertation brings the voices of not only Control Data executives but also middle managers and line workers into the company’s history, through both discovery and invitation
Rescuing Experience from the Hard Problem of Consciousness
No full textHow do we explain consciousness (defined, as it standardly is, in terms of phenomenal experience) in scientific terms? This problem is one central strand in what is known as the mind-body problem, a problem generated routinely by the dichotomy of the physical and the mental, viewing these as fundamental and exhaustive metaphysical categories with which to understand the world. Conceiving of the world in these terms leaves two core approaches to explaining consciousness. One is monist, according to which the world is either fundamentally physical or fundamentally mental.
On this view, consciousness is either something that infuses all of nature, everything in the world being in some sense ‘mental’, or consciousness is entirely reducible to the physical, everything in the world (including consciousness) being in some sense ‘physical’. By contrast, the dualist approach views the world as containing two sets of properties, the mental and the physical. On this view, consciousness is explained as fundamentally mental, but also as metaphysically distinct from the physical and therefore in need of unifying with the physical in some way.
I develop an alternative approach to understanding consciousness, drawing on Noam Chomsky’s work and his argument that we cannot formulate a ‘mind-body’ problem because we have no adequate conception of ‘the body’ with which to formulate it. According to Chomsky, the only conception of ‘the body’ that the sciences have known was to be found in the Early Modern conception of the world as a large-scale mechanism or ‘machine’ . This was the concept of ‘the body’ taken for granted by the ‘mechanical philosophy’, a scientific framework that viewed the world as operating in causal terms, made up of nothing but inanimate matter, whose essence was fixed by the properties of shape, size, and motion.
To explain the world physically meant demonstrating that every phenomenon and event (thus, every body) in it is mechanistically conceived in this sense. Chomsky points out that Newton undermined this worldview when he explained motion by a theory that gave a central place to a force (‘gravity’) that the theory itself cannot explain. Gravity is a force that acts on bodies at (often great) distances from each other, thus transcending the mechanistic idea that direct contact must be the condition of influence.
When Newton transformed physics into a discipline that mathematically characterizes the world in terms of a system of laws that explain every seemingly contingent feature in it, he produced a deterministic theory of all events that occur in the career of bodies in nature, without telling us what the nature of body, matter, or the physical is, in the sense that earlier mechanical natural philosophy sought to do. I use this dissolution of the notion of mechanism to ground my claim that monist-versus-dualist approaches to consciousness are unnecessarily restrictive to understanding consciousness, and in particular, its relation to the unconscious. My argument, further, will crucially turn on my claiming that endemic to the traditional approach is the systematic reduction of our experiential (and more generally, mental) lives, to the parts of it that are consciously accessible to us from the first-person point of view.
Drawing on the literature in linguistics, neuroscience and in trauma theory, I argue that our experiential life is more complex than this traditional picture of the mind suggests. One’s experiences, for instance, are not always consciously accessible, and yet may not be ‘physical’ in the traditional philosophical sense. By developing this alternative Chomskyan framework, I move away from monist-versus-dualist frameworks to understand experience, pursuing instead normative frameworks and trauma-theoretic frameworks to understand it. I argue that these frameworks are more explanatorily powerful than the traditional paradigm in explaining the nature of our experiential life
Aiding Complex Multimodal Reasoning with Contextual and Structural Information
No full textMultimodal reasoning involves integrating information from multiple data modalities —such as text, images, and videos — to perform a wide range of tasks, including Visual Question Answering, Visual Entailment, Captioning, Retrieval, and more. While current multimodal models have shown strong performance on these standard tasks, they often struggle with more complex scenarios that demand external knowledge, richer context, or the ability to process large and intricate data inputs. This thesis explores these challenging aspects of multimodal reasoning and proposes targeted solutions to help models overcome these limitations.
We focus on two broad categories of complex tasks: those that benefit from external context and those that benefit from structured representations of data. External context refers to additional information necessary for solving a task, beyond what is explicitly available in the input — for instance, knowledge from external sources or temporal context derived from surrounding data. Structured representations, on the other hand, involve organizing raw inputs into meaningful forms, such as graphs or hierarchies, which help simplify reasoning over complex or large-scale data. To address these challenges, we propose a set of complementary solutions. For tasks requiringexternal knowledge, we introduce methods that integrate information from sources such as Google Search and Large Language Models.
To address temporal context gaps, we develop techniques to extract relevant contextual cues from the source video surrounding the multimodal task instance. Additionally, to handle large or densely structured data, we propose methods that convert raw inputs into compact, structured representations — such as graphs or hierarchies — which make the data more accessible for models to interpret and reason over.
Collectively, the solutions proposed in this thesis aim to enhance the reasoning capabilities of multimodal models, equipping them to handle a broader spectrum of real-world scenarios. These advancements mark a step forward in improving the robustness and applicability of multimodal reasoning systems in domains such as general-purpose robotics, digital agents, autonomous driving, and beyond
Determinants of vector-borne avian pathogen occurrence in a mosaic of habitat fragmentation in California
Get PDFBackground
As habitat fragmentation increases, ecological processes, including patterns of vector-borne pathogen prevalence, will likely be disrupted, but ongoing investigations are necessary to examine this relationship. Here, we report the differences in the prevalence of Lyme disease (Borrelia burgdorferi sensu lato, s.l.) and haemoproteosis (Haemoproteus spp.) pathogens in avian populations of a fragmented habitat. B. burgdorferi s.l. is a generalist pathogen that is transmitted by Ixodes pacificus vectors in California, and Haemoproteus is an avian parasite transmitted by Culicoides vectors.
Methods
To determine whether biotic (avian and mammalian abundance) or abiotic characteristics (patch size and water availability) correlated with infection prevalence change, we screened 176 birds sampled across seven sites in oak woodland habitat in northern California.
Results
While biotic factors correlated with an increase in both pathogens, infection prevalence of Haemoproteus spp. was only associated with individual-level traits, specifically foraging substrate and diet, and B. burgdorferi s.l. was associated with community-level characteristics, both total mammal and, specifically, rodent abundance. Proximity to water was the only abiotic factor found to be significant for both pathogens and reinforces the importance of water availability for transmission cycles. Larger patch sizes did not significantly affect infection prevalence of Haemoproteus, but did increase the prevalence of B. burgdorferi.
Conclusions
These results highlight that while environmental factors (specifically habitat fragmentation) have a limited role in vector-borne pathogen prevalence, the indirect impact to biotic factors (community composition) can have consequences for both Haemoproteus and B. burgdorferi prevalence in birds. Given the pervasiveness of habitat fragmentation, our results are of broad significance. Graphical abstrac
Leonardeschi in Wartime: Giovanni Antonio Boltraffio, Giovanni Agostino da Lodi, and Andrea Solario after the French Occupation of Milan, 1499-1510
No full textGiovanni Antonio Boltraffio, Giovanni Agostino da Lodi, and Andrea Solario belong to a group of early modern artists referred to collectively as the “Leonardeschi,” so named because they worked in the orbit of Leonardo da Vinci (d. 1519) either directly (as pupils) or indirectly (as associates or followers). The dissertation reconsiders these three artists as products of their proximity not only to Leonardo and his first Milanese workshop, but also to a broader context of conflict and emergency in early sixteenth-century Milan.
Like Leonardo, they were subject to the pressures, upheavals, and opportunities that accompanied the deposing of Duke Ludovico Sforza in 1499/1500 and the subsequent French occupation, which, in its first stage, lasted until 1512. The Leonardeschi, as the appellation implies, are typically analyzed through the prism of Leonardo and his influence.
My dissertation orients instead around a group of thematic pressure points (material scarcity, disguise, and spoliation) that informed Leonardesque painting and drawing during the first decade of the French incursion. A different emphasis allows for new understandings of the early Leonardeschi, their artworks, and the turbulent world in which their artistic personalities developed
Nanomedicine for Transmucosal Delivery of Drugs and Genome Editors
No full textTransmucosal delivery—via oral and intranasal routes—offers a compelling alternative to injection-based administration of biologics, enhancing patient compliance, enabling site-specific action, and reducing systemic toxicity. However, mucosal surfaces present significant physiological barriers to large molecules, including enzymatic degradation, mucus entrapment, and limited epithelial permeability. This dissertation presents nanomedicine-based strategies for non-invasive delivery of gene editors, small molecules, and peptide therapeutics across mucosal barriers, validated through preclinical studies that span genome editing, anti-inflammatory therapy, and metabolic disease intervention.
To enable oral gene editing, we developed a β-glucan-coated polyplex nanoparticle designed to overcome gastrointestinal degradation and target gut-associated lymphoid tissues (GLATs) via Dectin-1–mediated uptake. The formulation exhibited strong mucosal stability, plasmid protection, and cellular uptake in vitro. In vivo, it achieved intestinal transgene expression and functional genome editing in CRISPR-reporter mice. Mechanistic studies confirmed its selective uptake by M cells and immune cells in Peyer’s patches, offering a promising strategy for GALTs-specific gene modulation without injections.
For inflammatory bowel disease (IBD), we synthesized fluoxetine–PEG conjugates to enhance local gastrointestinal retention and minimize systemic exposure. Multi-arm PEG scaffolds improved mucosal stability and boosted serotonin transporter binding. In DSS-induced colitis models, oral PEG–4–FLX significantly reduced weight loss, colon shortening, and histological inflammation. These results highlight the value of rational conjugation chemistry to reengineer systemically active drugs for targeted, safer anti-inflammatory therapy within the gut.
To treat obesity through central nervous system pathways, we developed an intranasal polymeric nanoparticle for delivery of GLP-1 receptor agonists. This platform bypassed the blood–brain barrier via olfactory transport, enabling selective accumulation in specific brain regions. In diet-induced obese mice, treatment led to sustained weight loss, reduced food intake, and promising glycemic control. The approach minimized peripheral exposure and side effects, supporting intranasal delivery as a feasible, non-invasive strategy for targeting brain circuits in metabolic disease.
Collectively, this dissertation demonstrates the potential of nanomedicine-enabled transmucosal delivery to administer a diverse array of therapeutic modalities without injection. By integrating rational design with disease-specific needs, this work provides a foundation for translating non-invasive gene and drug therapies to the clinic across inflammatory, genetic, and metabolic disorders
Comprehensive Multimodal Profiling of Atherosclerosis Reveals Bhlhe40 as a Potential Regulator of Vascular Smooth Muscle Cell Phenotypic Modulation
No full textBackground:
Atherosclerosis is an inflammatory disease of the arterial vessels characterized by the accumulation of lipids and cells such as vascular smooth muscle cells (VSMCs), endothelial cells, fibroblasts, and immune cells, which form a plaque or lesion that obstructs proper blood flow. Studies have shown that the high lipid and inflammatory micro-environment within atherosclerotic plaques drive the phenotypic modulation of VSMCs from their contractile state to multiple modulated states such as fibroblast-like, myofibroblast-like, osteoblast-like, and macrophage-like states; as well as their uptake of lipids to form VSMC foam cells. While these modulated states have been well recognized in the field, the transcriptomic profile and molecular drivers underlying VSMC phenotypic modulation in atherosclerosis progression remain under characterized.
Methods:
In this study, we aimed to understand how VSMCs transition to macrophage-like and lipid-rich foam cells during atherosclerosis progression and the molecular factors regulating this process. We first performed a multiomics study using single-cell RNA and CITE-seq, on a lineage tracing atherosclerotic Ldlr-/- mouse model fed with a high-fat diet at multiple time points (each time point reflective of disease progression). This allowed for the identification of VSMCs and their derived cell types in atherosclerotic lesions in vivo. Our multiomics study and immunohistochemical staining were also extended to human atherosclerotic lesions to study the transcriptomic profile and differentially expressed proteins unique to VSMCs, their subtypes, and phenotypically modulated states during disease progression, including VSMC-macrophage-like cells and VSMC-foam cells.
Furthermore, to understand the modulation of contractile VSMCs to VSMC foam cells, we conducted bulk RNA sequencing of atherosclerotic plaques from conditional VSMC-lineage tracing Ldlr-/- mouse models maintained on a high-fat diet. Using LipidTox staining, VSMCs and VSMC-derived foam cells were identified and isolated using flow cytometry at key time points representing late and advanced stages of disease progression and further sequenced to characterize their genomic profile and identify a panel of key transcriptional regulators upregulated in late to advanced stages of atherosclerosis progression. Further re-analysis of our single-cell data on the expression pattern of these transcription regulators showed their expression within VSMC subpopulations at the single-cell level, with the transcription factor Bhlhe40 showing the highest specificity of being differentially expressed in modulated VSMC clusters. To understand the functional role of Bhlhe40, we performed an siRNA knockdown of Bhlhe40 in primary mouse VSMCs under atherosclerotic stress induced by TNFα and MBD-Cholesterol.
Results:
Our single-cell analysis revealed that VSMC-derived macrophage-like cells are a rare cell population even in advanced stages of atherosclerosis, while a substantial number of VSMC-lineage foam cells existed in mouse atherosclerotic lesions. Histological studies utilizing immunohistochemistry and in situ hybridization provided additional critical insights into the localization of rare VSMC-derived macrophage-like cells within atherosclerotic lesions. Notably, these studies further showed that in both mice and humans, VSMC-derived macrophage-like cells are very few compared to their myeloid-derived counterparts in lesions.
In contrast, lipid staining combined with bulk RNA sequencing analyses demonstrated that approximately 70% of foam cells in advanced lesions are derived from VSMCs. These VSMC-derived foam cells showed enrichment in gene pathways associated with proliferation, migration, and cancer-related transcription factors, supporting the hypothesis that VSMC-derived cells in atherosclerosis exhibit characteristics akin to tumor biology.
Our findings also reveal that the expression of the Basic Helix-Loop-Helix Family Member E40, Bhlhe40 (also known as Dec1), a pro-inflammatory transcription factor, is activated in VSMC-derived foam cells during atherosclerosis progression and enriched in modulated and proliferative VSMC-derived cells measured by scRNA-seq of atherosclerotic lesions in mice and humans. Upstream regulator analysis suggests that Bhlhe40 may play a pivotal role in driving the differentiation of VSMCs into foam cells. Furthermore, functional in vitro studies in mouse primary VSMCs showed that siRNA Bhlhe40 knockdown inhibits VSMC phenotypic modulation and lipid uptake during atherosclerotic stress induced in vitro.
Conclusions:
These findings advance our understanding of VSMC phenotypic modulation in atherosclerosis and identify Bhlhe40 as a regulator of VSMC foam cell formation during development and progression of atherosclerosis. Elucidating the molecular and transcriptomic landscape of VSMC-modulated cells will significantly contribute to the field and address key gaps in the current understanding of atherosclerosis while offering potential pathways for innovative therapeutic strategies
Nano-optics and Nano-photocurrents in van der Waals Quantum Materials
No full textIn this dissertation, we will use local and nonlocal detection of scanning nearfield signals to unravel emerging quantum phenomena in van der Waals quantum materials at nanoscale.
In Chapter 1, we will introduce the materials and methodologies for this dissertation. Two prototype van der Waals material systems, graphene and transition metal dichalcogenides (TMD) with their unconventional allotropes will be discussed. We will also introduce the measurable quantities and principles for using multi-messenger scanning nearfield optical microscopy to study van der Waals materials.
In Chapter 2 and 3, we will focus on nearfield light-matter interactions in monolayer graphene subject to DC currents. Specifically, we will discuss the discovery of Fizeau drag effect in graphene plasmonics in Chapter 2, and currrent-driven nonequilibrium effects probed by nano-optics and nano-photocurrents in Chapter 3.
In Chapter 4, we will reveal the flatband excitons in a three-dimensional super-twisted transition metal dichalcogenide, as well as its other unique properties.
In Chapter 5, we will discuss the quantum geometric photocurrents in crystalline multilayer graphene, with intrinsic domainless ferroelectricity probed by shift current.
In conclusion, with a series of original discoveries in graphene and TMD, this dissertation establishes nano-optics and nano-photocurrents as sensitive probes of the emerging quantum properties in van der Waals materials at a range of temperatures and energy scales
Innate spectral preference and multisensory learning mechanisms in D. Melanogaster
No full textLight plays a multifaceted role in shaping behavior, yet the innate value of different wavelengths and their role in learning remain poorly understood. Here, I investigate how Drosophila Melanogaster uses spectral cues to guide both innate phototaxis and learned olfactory associations. Using a high-throughput Y maze assay, I systematically characterize innate preferences across a broad range of wavelengths and intensities.
I show that phototactic behavior can be explained by two principal components—an achromatic and a chromatic axis—that together account for over 90% of behavioral variance. To trace the neural basis of these behaviors, I map photoreceptor contributions to phototaxis from the retina through the lobula. I further test the hypothesis that spectral light carries innate valence signals that can reinforce associative learning. Using monochromatic light as an unconditioned stimulus in a classical conditioning paradigm, I demonstrate wavelength- and intensity-dependent learning: violet light elicits either appetitive or aversive associations depending on intensity, while blue light consistently drives aversive learning. These effects are modulated by PAM and PPL1 dopaminergic circuits, as wellas by Rh7 and CRY photoreceptor pathways.
Finally, I show that spectral cues can also function as contextual signals in multisensory learning, enabling flies to retrieve odor memories in a context-dependent manner. Functional imaging had revealed that UV light robustly activates γd Kenyon cells (KCs), with a majority of responses being UV-selective. Consistent with these responses, I show that flies can use UV as a contextual cue to associate odors with reward. The extent of contextual learning varied by wavelength, with UV vs dark supporting it best, and blue, amber, and red showing limited or no support. In addition, our results suggest extinction-like dynamics, aligning with a reinforcement learning framework. Together, these results reveal that spectral information carries both innate and learned value, and they outline a circuit framework for how light guides complex behaviors in the fly brain
Probing graphene heterostructures with atomic force microscopy techniques
No full textThe ability to control and probe the properties of van der Waals (vdW) heterostructures, particularly twisted graphene-based systems, has become a key area of research in the field of experimental condensed matter physics. These systems exhibit unique electronic and mechanical behaviors which are highly tunable using various parameters such as the relative rotational twist angle between layers, strain, and material combinations. When two layers of vdW materials are stacked with slight rotational misalignment or placed on substrates with differing lattice constants, they form a moiré superlattice which can dramatically alter the material's electronic band structure.
These superlattices can give rise to unique physical phenomena, including correlated electronic states, exotic phases of matter, and unusual transport properties, making the control and characterization of them an area of significant interest in condensed matter physics research. Beyond playing host to an array of tunable correlated electronic phenomena, these moiré systems are also promising for applications within quantum sensing, optoelectronics, and nanostructure engineering. However, much of the research thus far on fundamental physics and applications of moiré phenomena has been conducted under cryogenic conditions, often with high-quality, small-area samples exhibiting low levels of disorder.
This dissertation addresses the challenge of controlling moiré disorder and gaining real-time feedback while characterizing and studying these vdW systems at room temperature, where disorder and its impact on the material properties become more significant. It focuses on the development of novel experimental approaches to manipulate and characterize moiré superlattices in situ, providing new insights into how two-dimensional moiré systems can be controlled and measured. The materials studied primarily consist of graphene and hexagonal boron nitride (hBN), and the characterization was carried out using a variety of atomic force microscopy (AFM) techniques, including lateral force microscopy (LFM), piezoresponse force microscopy (PFM), and conductive AFM (CAFM).
The results underscore the atomic force microscope as an indispensable tool for the characterization of emerging two-dimensional quantum materials. Its versatility in ambient conditions demonstrate it to be powerful in not only controllably straining and manipulating moiré heterostructures, but also in effectively characterizing the complex domain structures within these systems across a range of length scales, capturing the fine details of moiré patterns, strain-relaxation processes, and domain-dependent material behaviors. The ability to study these materials in situ at room temperature opens new possibilities for understanding the relationship between disorder, structure, and electronic behavior in graphene-based moiré systems. This work contributes to the development of new strategies for engineering vdW materials with tailored properties, and offers valuable insights into the potential to correlate the structural variations of the moiré pattern with the macroscopic transport properties of the material