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Synthetic Studies Of (–)-Gukulenin A, Joshua Benjamin Combs Oct 2022

Synthetic Studies Of (–)-Gukulenin A, Joshua Benjamin Combs

Yale Graduate School of Arts and Sciences Dissertations

In this thesis, I describe our progress towards the synthesis of the cytotoxic tetraterpenoid (–)-gukulenin A (1). (–)-Gukulenin A (1) is a challenging target for synthesis due to its congested syn-syn-quaternary cyclopentanes, tri-substituted and tetra- substituted α-tropolone moieties, and central ethyl-keto bridging subunit. (–)-Gukulenin A (1) has produced a dose-dependent reduction in the size of grafted human ovarian cancer tumors (A2780) in a murine model. Although the mechanism of action is unknown, it has been established that (–)-gukulenin A (1) associated cell death is reliant upon the activation of procaspases-3, -8, and -9. Access to dimeric gukulenin A (1) derivatives …

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The Atomic Distributed Object Model For Distributed System Verification, Wolf Honore Oct 2022

The Atomic Distributed Object Model For Distributed System Verification, Wolf Honore

Yale Graduate School of Arts and Sciences Dissertations

Distributed systems are at the heart of most web-based applications and are responsible for replicating and maintaining critical data. Unfortunately, their inherent concurrency combined with an asynchronous and unreliable network makes them prone to implementation bugs that can have serious real-world consequences. Formal verification can offer strong assurances of correctness; however, despite recent advances, reasoning directly about a system's implementation remains prohibitively complex. The key is to find the right abstraction that faithfully models a system's behaviors, while avoiding irrelevant implementation details. This dissertation presents such an abstraction called the atomic distributed object (ADO) model, which hides the existence of …

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Constraining Dark Matter With Gravitational Heating And Cooling Processes, Dhruba Dutta Chowdhury Oct 2022

Constraining Dark Matter With Gravitational Heating And Cooling Processes, Dhruba Dutta Chowdhury

Yale Graduate School of Arts and Sciences Dissertations

About $84 \%$ of the total mass budget of the Universe consists of dark matter. While it does not interact electromagnetically and, therefore, cannot be “seen”, one can hope to infer its properties from its gravitational imprints on the structure and dynamics of various astrophysical objects (e.g., star clusters, black holes, galaxies). While cold dark matter, where dark matter is collisionless and most likely consists of weakly interacting massive particles (WIMPs), is the most widely studied dark matter model, WIMPs remain undetected. An intriguing alternative is Fuzzy Dark Matter, where dark matter is made up of ultralight bosons with masses …

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Lipid Transfer Proteins At Membrane Contact Sites Between The Endoplasmic Reticulum And Mitochondria, Andres Guillen Samander Oct 2022

Lipid Transfer Proteins At Membrane Contact Sites Between The Endoplasmic Reticulum And Mitochondria, Andres Guillen Samander

Yale Graduate School of Arts and Sciences Dissertations

The Endoplasmic Reticulum (ER) is a subcellular compartment distributed throughout the entire cytosol which plays a variety of functions in cell physiology, including synthesis of most membrane lipids. From the ER, lipids can be transported to other membranous organelles. This process can occur via two mechanisms: vesicular trafficking, in which lipids are transported as part of the membrane of vesicular carriers, and protein-mediated lipid transfer, in which lipids are carried between two membranes within the hydrophobic pocket of a protein. Many of these proteins act at membrane contact sites, where the short distance between two organelles enhances the efficiency and …

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Decoding Immunometabolism In Inflammatory Macrophages, Zheng Wei Oct 2022

Decoding Immunometabolism In Inflammatory Macrophages, Zheng Wei

Yale Graduate School of Arts and Sciences Dissertations

The mammalian innate immune system uses a variety of pattern recognition receptors (PRRs) to recognize foreign pathogen-associated molecular patterns (PAMPs) and host damage-associated molecular patterns (DAMPs) and transduce the upstream signals from the cell membrane and intracellular receptors to core downstream immunometabolic signaling outcomes, including the secretion of proinflammatory cytokines and the production of critical reactive oxygen species (ROS), reactive carbonyl species (RCS), and reactive nitrogen species (RNS). Orchestration and resolution of these inflammatory outcomes are indispensable to healthy innate immune function. Correspondingly, their dysregulation is associated with various inflammatory diseases and an impaired ability to resolve bacterial and viral …

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How The Tropical Pacific Responds To Global Warming, Ulla K. Heede Oct 2022

How The Tropical Pacific Responds To Global Warming, Ulla K. Heede

Yale Graduate School of Arts and Sciences Dissertations

The emerging warming patterns in the tropical Pacific are key to understanding earth’s climate response to increasing greenhouse gases (GHGs). This is true on interannual timescales dominated by El Niño/Southern Oscillation (ENSO), and on decadal and longer timescales, as Pacific trade wind variations and ENSO decadal modulation can influence temporary global warming trend slowdowns with links to climate sensitivity. While it is imperative to understand and predict changes in the tropical Pacific, progress is hindered by discrepancies between models and observations, diverging theories and uncertainty in projections. My thesis tackles these outstanding problems through five chapters. The first chapter provides …

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Formation Of Fused Ring Junction N-Heterocycles Via Cp*Rh(Iii) Imidoyl C–H Activation And Application To Rna Targeting, Andrew Douglas Streit Oct 2022

Formation Of Fused Ring Junction N-Heterocycles Via Cp*Rh(Iii) Imidoyl C–H Activation And Application To Rna Targeting, Andrew Douglas Streit

Yale Graduate School of Arts and Sciences Dissertations

Nitrogen heterocycles are present in almost two-thirds of U.S. FDA approved pharmaceuticals, garnering interest in the ability to rapidly access these structures displaying different functional groups. The first two chapters of this dissertation will discuss develop-ment of Cp*Rh(III)-catalyzed C–H activation to rapidly access two different classes of 5.6-fused nitrogen heterocycles. The third chapter describes the application of these heterocycles to the validation of a novel whole transcriptome RNA screen.Chapter 1 describes a three component reaction for the rapid assembly of pyra-zolopyrimidines from commercially available aminopyrazoles, aldehydes, and sulfoxo-nium ylides. The method was optimized for setup without the use of an …

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How Do Cognitive Demands During Encoding Influence Subsequent Memory Across Development, Lena Jane Skalaban Oct 2022

How Do Cognitive Demands During Encoding Influence Subsequent Memory Across Development, Lena Jane Skalaban

Yale Graduate School of Arts and Sciences Dissertations

Context greatly impacts what information is encoded and retrieved by different memorysystems. Development is one such context that shifts what information is prioritized and subsequently remembered. Despite an abundance of studies on the development of different forms of memory across the life course, much of this research assesses specific types of memory compared to an adult baseline, rather than examining the interaction of these memory systems at different points in development. In this dissertation, I investigate how development influences what information is encoded and retained in three core memory systems: working memory, recognition memory, and episodic memory. I demonstrate that …

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Electrons On The Move In Proteins: Microbial Cytochrome Nanowires In Extracellular Electron Transfer And As Functional Materials, Catharine Cerise Shipps Oct 2022

Electrons On The Move In Proteins: Microbial Cytochrome Nanowires In Extracellular Electron Transfer And As Functional Materials, Catharine Cerise Shipps

Yale Graduate School of Arts and Sciences Dissertations

Proteins are commonly known to transfer electrons over distances limited to a few nanometers. However, many biological processes require electron transport over far longer distances. For example, some soil and sediment bacteria transport electrons over hundreds of micrometers to even centimeters. In particular, Geobacter sulfurreducens uses extracellular electron transfer (EET) to move respiratory electrons from the cytoplasm to external electron acceptors such as minerals or external electrodes in biofilm growth. These terminal acceptors are mere microns to as far as thousands of times the length of a cell away in biofilms. The exact mechanisms for the EET pathway and the …

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The Role Of Type I Ifns In Fasting Metabolism, Kavita Israni-Winger Oct 2022

The Role Of Type I Ifns In Fasting Metabolism, Kavita Israni-Winger

Yale Graduate School of Arts and Sciences Dissertations

The immune system has a versatility of functions beyond its response to foreign pathogens. This is the case not only in inflammatory perturbations but in sterile challenges as well. Here we present a role for the family of immune cytokines, type I IFNs, in maintaining homeostasis and mediating adaptation during prolonged food deprivation. We demonstrate that through glucocorticoid mediated upregulation of endogenous retroviral elements (ERVs), cyclic GMP-AMP synthase/stimulator of interferon genes (cGAS/STING) pathway is activated and upregulates unique subsets of type I IFNs. These IFNs are necessary for metabolic adaptation that ensures survival of the organism when no food is …

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Depicting The Russian North: Modernity, Antimodernism, And The Arts, 1890–1910, Ingrid C. Nordgaard Oct 2022

Depicting The Russian North: Modernity, Antimodernism, And The Arts, 1890–1910, Ingrid C. Nordgaard

Yale Graduate School of Arts and Sciences Dissertations

This dissertation addresses how and why the Russian north—defined here as the imperial governorates of Arkhangelsk, Olonets, and Vologda—became a desired destination for Russian artists and writers in the period 1890-1910. I argue that the Russian north perfectly embodied both their discontent with and their triumphant faith in modernity, and that their depictions of the region reflected antimodern sentiments which were themselves constitutive elements of Russian modernity. At the core of this project is the notion that antimodernism is a philosophical orientation that signals both support of and protest against the processes of modernity and modernization.In the depictions of the …

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Elucidating The Mechanisms Of Water And Ion Transport Under Nanoconfinement, Cody Lee Ritt Oct 2022

Elucidating The Mechanisms Of Water And Ion Transport Under Nanoconfinement, Cody Lee Ritt

Yale Graduate School of Arts and Sciences Dissertations

Water scarcity is among the most prominent humanitarian crises of our time. Achieving equitable access to safe drinking water for all humankind necessitates the treatment of unconventional and underutilized sources. Pressure-driven desalination technologies are particularly well-suited for augmenting global water supplies due to their energy efficiency. In these technologies, the membrane is the critical component driving process efficacy and requires material breakthroughs to achieve paradigm-shifting performance. Attempts to improve conventional membrane materials and investigations into numerous novel materials have failed to produce the next generation of desalination membranes due to our limited understanding of the mechanisms that govern water and …

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Three Essays On Distributive Politics In India, Shikhar Singh Oct 2022

Three Essays On Distributive Politics In India, Shikhar Singh

Yale Graduate School of Arts and Sciences Dissertations

This dissertation presents three essays on distributive politics in India: 1) Governments distribute a variety of benefits to win votes. Why do some benefits have greater electoral impact than others? This paper provides descriptive evidence that a $10 cooking gas cylinder and $2000 house have comparable electoral impact in India. This motivates a typology in which distributive decisions can be organized on two dimensions: the cost of a benefit, and how it is distributed. Politicians face two key trade-offs: first, given a finite budget, they can widely distribute a cheap benefit or give an expensive benefit to fewer voters; and …

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Provisioning 3d Wireless Coverage For Programmable Radio Spaces, R. Ivan Zelaya Oct 2022

Provisioning 3d Wireless Coverage For Programmable Radio Spaces, R. Ivan Zelaya

Yale Graduate School of Arts and Sciences Dissertations

Wireless connectivity forms the backbone of diverse IoT services. New consumer gadgets are being deployed in an unprecedented and unplanned manner, leading some to experience uneven coverage and suboptimal network performance. As IoT devices continue to diversify, network administrators are increasingly contending with managing wireless signal propagation in complex 3D geometries. Until recently, typical IoT designs tended to be endpoint-centric, reflected in radio or protocol designs at the endpoints of a wireless link. However, they are ill-suited to shaping the signal after transmission, and hence are far from the most effective signal shapers. Instead, recent environment-centric proposals customize the radio …

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Mechanisms Of Protein Quality Control At The Nuclear Envelope And During Nuclear Pore Complex Biogenesis, Sarah M. Prophet Oct 2022

Mechanisms Of Protein Quality Control At The Nuclear Envelope And During Nuclear Pore Complex Biogenesis, Sarah M. Prophet

Yale Graduate School of Arts and Sciences Dissertations

Collapse of protein quality control (PQC) is a defining feature of numerous neurological diseases. Work described within this thesis argues that DYT1 dystonia, a neurological movement disorder of unclear etiology, arises due to a PQC defect. While it is clear that mutations in the AAA+ ATPase TorsinA cause this disease, it is not known why loss of this protein function causes DYT1 dystonia. In cells lacking Torsin function, nuclear pore complexes (NPCs) fail to be properly assembled. Instead, nuclear envelope (NE) herniations form that sequester abundant molecular chaperones. Ubiquitylated proteins, that in healthy cells are rapidly degraded, become sequestered with …

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Investigation Of Various Organocatalytic Modes In Asymmetric Transformations: Controlling Different Elements Of Chirality, Sooyun Choi Oct 2022

Investigation Of Various Organocatalytic Modes In Asymmetric Transformations: Controlling Different Elements Of Chirality, Sooyun Choi

Yale Graduate School of Arts and Sciences Dissertations

The ubiquity of stereogenic elements both found in nature and encountered in our daily lives has necessitated the control of chirality in chemical synthesis. This dissertation describes the study of Brønsted acidic, Lewis basic and anion-binding catalysis, all moderated within organic chiral scaffolds to control different elements of chirality, including diastereoisomerism, point chirality and atropisomerism.In Chapter 2, BINOL and peptidic phosphoric acids were evaluated in the development of an atroposelective catalytic cyclodehydration to afford 1,2,4-triazoles, obtained with up to 88:12 er. The enantioenriched products obtained via chiral phosphoric acid catalysis were recrystallized and isolated as enantiopure samples, demonstrating the first …

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Thz Spectroscopy Of Photoconductive Metal-Organic Frameworks, Sarah Ostresh Oct 2022

Thz Spectroscopy Of Photoconductive Metal-Organic Frameworks, Sarah Ostresh

Yale Graduate School of Arts and Sciences Dissertations

The development of devices for renewable energy generation and storage is becoming increasingly important as climate challenges persist. This dissertation focuses on the investigation of materials that are used for photoelectrochemical water splitting. Photoelectrochemical cells (PECs) are composed of semiconducting materials that can absorb solar radiation and store it in the form of chemical bonds or for solar fuel generation. Wide bandgap semiconductors are often incorporated in these devices to be photoexcited by solar radiation and remain in a charge separated state long enough to generate a current. In an effort to increase efficiency, metal oxides have been functionalized with …

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Robots That Tutor In Complex And Dynamic Environments, Nicole Salomons Oct 2022

Robots That Tutor In Complex And Dynamic Environments, Nicole Salomons

Yale Graduate School of Arts and Sciences Dissertations

Robots have shown great promise in being effective tutors for both children andadults. For instance, they have been shown to be successful in math tutoring for children [203], interruptions training for adults with Autism Spectrum Disorder [204], and assisting the elderly while exercising [87]. Yet, despite the great potential of tutoring robots, most studies have focused on providing short-term tutoring either in a laboratory or a school while the researcher is present. For robots to be more broadly successful, users need to be able to practice skills on a more prolonged basis and in the wild. This requires robotic systems …

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The Ambassadors: Indigenous Democracy And American Monarchy After The War Of 1812, Zachary Conn Oct 2022

The Ambassadors: Indigenous Democracy And American Monarchy After The War Of 1812, Zachary Conn

Yale Graduate School of Arts and Sciences Dissertations

This dissertation investigates sites of state activity in the early United States which have received far less attention from historians than executive mansions, legislative halls, courtrooms, military outposts, or overseas embassies: the numerous embassies the federal government maintained on, or adjacent to, lands belonging to North America’s sovereign Indigenous polities. At the helm of each of these embassies, known as Indian agencies, sat a presidentially appointed ambassador known as the Indian agent. I argue that Indian agents were monarchical officers within a republican system, compelled to follow diplomatic scripts originating in the centuries of contact between European monarchies and Indigenous …

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The Role And Production Of Gut Food-Specific Immunoglobulin A, Elise Liu Oct 2022

The Role And Production Of Gut Food-Specific Immunoglobulin A, Elise Liu

Yale Graduate School of Arts and Sciences Dissertations

Immunoglobulin A (IgA) is the predominant antibody isotype in the gut, where it regulates commensal flora and neutralizes toxins and pathogens. The function of food-specific IgA in the gut is unknown but is presumed to protect from food allergy. Specifically, it has been hypothesized that food-specific IgA binds ingested allergens and promotes tolerance by immune exclusion; however, the evidence to support this hypothesis is indirect and mixed. While it is known that healthy adults make gut peanut-specific IgA, it is unclear whether children also have gut peanut-specific IgA. We found that in a cohort of non-food allergic infants (n=112), there …

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The Evolution Of The Surface Lithium Cycle Through Earth’S History, Boriana Kalderon-Asael Oct 2022

The Evolution Of The Surface Lithium Cycle Through Earth’S History, Boriana Kalderon-Asael

Yale Graduate School of Arts and Sciences Dissertations

In order to sustain habitability on our planet – Earth, a fine balance between the inputs and outputs of atmospheric carbon dioxide must be maintained. New steady states have emerged throughout the Earth’s history as the nature is dynamic. Yet, the carbon cycle seems to have been stabilized by the silicon cycle and the two cycles evolved concertedly together, contributing to the long-term stability of the Earth’s climate. Explicitly, silicate weathering, occurring both in terrestrial and marine environments, provides negative feedback to fluctuations in atmospheric carbon dioxide concentrations. Direct observations not being available, we often resort to geochemical proxies and …

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Impact And Cost-Effectiveness Of Human Papillomavirus Vaccination Policies In The United States Uniformed Armed Forces, Noel Dickens Oct 2022

Impact And Cost-Effectiveness Of Human Papillomavirus Vaccination Policies In The United States Uniformed Armed Forces, Noel Dickens

Yale Graduate School of Arts and Sciences Dissertations

Background. Virtually all cervical cancers and cases of recurrent respiratory papillomatosis (RRP) are caused by human papillomavirus (HPV) as well as a large proportion of anal, penile, oropharyngeal, vulvar, and vaginal cancers and anogenital warts (AGW). Vaccination with the nonvalent HPV vaccine (9vHPV) is proven to prevent a significant proportion of HPV-associated diseases. Adoption of large-scale HPV vaccination programs by US public institutions requires careful consideration of the cost to benefit ratio of each program through economic evaluations. US Uniformed Armed Forces (USUAF) HPV vaccination policy would benefit from economic evaluations that consider the unique population and institutional characteristics of …

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Virtue Signals: Narrative, Self-Transformation, And Behavioral Exemplarity In Xv-Century Italian Renaissance Humanist Biography In Poland And Ukraine, Michael Thomas Lo Piano Oct 2022

Virtue Signals: Narrative, Self-Transformation, And Behavioral Exemplarity In Xv-Century Italian Renaissance Humanist Biography In Poland And Ukraine, Michael Thomas Lo Piano

Yale Graduate School of Arts and Sciences Dissertations

This dissertation approaches the question which follows: who was the first Renaissance humanist in the Polish Crown Lands? As such, it attempts to reconcile the scholarly debate across a number of linguistic traditions regarding the identity and origin of the humanist movement in East Central Europe. It principally focuses on the Tuscan humanist Filippo Buonaccorsi (Callimachus Experiens) and his biography of Archbishop Grzegorz of Sanok entitled the Vita et mores Gregorii Sanocei. It examines the literary structure and form of the biography to assess Buonaccorsi’s claims regarding the origins of humanism in the Polish Crown Lands and evaluates these claims …

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The Role Of Xenobiotic Metabolizing Enzymes In Liver And Colon Carcinogenesis, Yewei Wang Oct 2022

The Role Of Xenobiotic Metabolizing Enzymes In Liver And Colon Carcinogenesis, Yewei Wang

Yale Graduate School of Arts and Sciences Dissertations

Both liver and colon cancers comprise the heterogeneous complex array of disorders, ranking the most common malignancies worldwide [1-3]. In 2022, the estimated 41,260 new cases of liver cancers and 106,180 new cases of colon cancers diagnosed in the United States, with 30,520 and 52,580 estimated deaths of corresponding cancers [4, 5]. A combination of surgery, chemotherapy, and/or radiotherapy is currently used to treat these cancers, and the five-year survival rate remains low for most of them [1-5]. This high lethality makes liver and colon cancers a major public health issue [6-11]. Despite extensive efforts over decades to characterize the …

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Influence Of Odor Plume Properties On Behavioral Decisions And Odor Representations In The Mouse Olfactory Bulb, Ankita Gumaste Oct 2022

Influence Of Odor Plume Properties On Behavioral Decisions And Odor Representations In The Mouse Olfactory Bulb, Ankita Gumaste

Yale Graduate School of Arts and Sciences Dissertations

Animal survival in the wild is largely dependent on their ability to locate food sources, find mates, and avoid predators — tasks which are all heavily reliant on their sense of smell. However, to be adept at these behaviors, animals must navigate a complex odor landscape where odors cues can be released in many forms, including odor trails and airborne odor plumes. Odor plumes result when an odor is carried by ambient wind, where it’s structure changes with distance from the odor source, providing potential navigational cues to searching animals. Odor plumes can adopt a variety of structures depending on …

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Sooting Tendencies And Soot Formation Pathways Of Alternative Fuels And Compounds, Junqing Zhu Oct 2022

Sooting Tendencies And Soot Formation Pathways Of Alternative Fuels And Compounds, Junqing Zhu

Yale Graduate School of Arts and Sciences Dissertations

In the modern age, human activities depend more and more on energy. Fossil fuels and the related combustion process play important roles in supplying global energy. However, fossil fuels emit CO2 and pollutants into the atmosphere when they combust. CO2 leads to global warming with a single half-life of more than hundreds of years in the atmosphere. In order to contain the rise of the average global temperature, net emissions of CO2 must approach zero. However, given the high energy density of liquid fuels relative to other energy carriers, such as batteries, liquid fuels are likely to remain the dominant …

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Immunology, Immunopathology, And Immunopharmacology Of Covid-19, Tianyang Mao Oct 2022

Immunology, Immunopathology, And Immunopharmacology Of Covid-19, Tianyang Mao

Yale Graduate School of Arts and Sciences Dissertations

Respiratory viruses represent a continuous and growing threat to humanity. This is exemplified by the ongoing global COVID-19 pandemic, which is caused by a newly emerged coronavirus SARS-CoV-2. The immune system provides a formidable barrier to viral pathogens, while dysregulated immunity leads to deleterious infection outcomes. Understanding the involvement of immune responses in viral infections will provide crucial insights into disease pathogenesis and shed light on potential targets for therapeutic interventions. In this thesis, we interrogate the components of the immune response that control SARS-CoV-2 and contribute to its pathogenesis. Based on these insights, we develop distinct immunopharmacological strategies to …

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Stellar Surfaces In The Frequency Domain, Joel Ong Oct 2022

Stellar Surfaces In The Frequency Domain, Joel Ong

Yale Graduate School of Arts and Sciences Dissertations

The analysis and interpretation of stellar oscillations — asteroseismology — illuminates a vast and diverse range of physical and astronomical phenomena. In particular, convectively excited pressure waves (p-modes), like those seen in the Sun, permit strong constraints on both the global properties and interior structures of cool stars. However, our efforts to reconcile asteroseismic observations with astrophysical theory are hindered by methodological systematic errors, associated with deficiencies in numerical treatments of stellar surfaces — the asteroseismic "surface term". These errors must be corrected for in the process of performing such analysis. Aside from the Sun, measurements of solar-like p-modes are …

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Essays In Behavioral Finance And Asset Pricing, Joao Paulo Valente Oct 2022

Essays In Behavioral Finance And Asset Pricing, Joao Paulo Valente

Yale Graduate School of Arts and Sciences Dissertations

This dissertation consists of three self-contained essays studying asset prices movements. The first essay investigates the impact of beliefs on exchange rates movements. Motivated by the evidence of systematic forecast errors by market participants and professional forecasters, we construct an exchange rate determination model with two frictions. (1) each investor receives noisy private signals about the future path of interest rate differentials between the U.S. and other countries, and (2) they overestimate the persistence of interest rate differentials. The model can explain the failure of UIP found in the data and other regularities of exchange rate returns, highlighting the importance …

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The Origin Of The Modern Bird Skull, With A Focus On The Evolution And Embryonic Development Of Musculoskeletal Structures In The Temporal And Otic Regions, Michael Hanson Oct 2022

The Origin Of The Modern Bird Skull, With A Focus On The Evolution And Embryonic Development Of Musculoskeletal Structures In The Temporal And Otic Regions, Michael Hanson

Yale Graduate School of Arts and Sciences Dissertations

Compared with their Mesozoic theropod ancestors, extant birds (Aves) exhibit extensively modified skulls and associated soft tissue, with massively enlarged brains and reduced temporal musculature, an inner ear with dorsally elongated semicircular canals, and cranial kinesis allowing independent beak movements that permit it to be a dexterous manipulatory organ. This kinetic system in turn occurs in two distinct forms—palaeognathous and neognathous, the latter having a novel joint in the palate. Through µCT scanning and confocal microscopy, the evolution and development of these skull modifications can now be explored in three dimensions. I digitally reconstructed 3D skulls of two Cretaceous toothed …

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