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Archaeological Insights into the Role of Religion in Funerary Rituals of Early Colonial Delaware: The Elkins Site Burial Ground Case Study
No full textThe Elkins site burial ground is located in New Castle, Delaware. The first record
of land ownership is from 1864, when Amos Nichols purchased the property. The Elkins
site comprises a house site and a small burial ground, consisting of five sets of skeletal
remains: one sub-adult male, two adult females, and two adult males. The ancient DNA evidence suggests that all five skeletons belonged to people of European descent. The Delaware Valley was a region of significant European migration during the seventeenth
and eighteenth centuries. There is a lack of research on the burial practices of early Americans within the Delaware Valley. By further examining the burials discovered at the Elkins site burial ground, it is possible to gain a deeper understanding of the role of
religion in these funerary rituals. This thesis focused solely on the remains located in the burial ground at The Elkins site burial ground. The burials were examined to compare with other cemeteries
dating to the same time frame, as well as nearby cemeteries. The primary focus was on the positions in which the individuals were buried, hand placement, burial shrouds, as
examined through the analysis of shroud pin usage, as well as the shape and lid style of
the coffins in which the individuals were interred. The Elkins burial ground yielded no grave goods other than pins, which were identified as shroud pins. By examining other nearby burial grounds, it was believed that this thesis would provide more information about the role of religion in funerary rites within eighteenth-century Delaware; however,
the available data was insufficient to draw a definitive conclusion.Extension Studie
Simultaneous in situ measurements of B cell clonality and single cell transcriptomes
No full textThe B cell response to antigen is carried out within various compartments of different tissues. B cell pathologies often coincide with a malformation of one or many of these tissue compartments, highlighting a direct connection between tissue organization and dysregulation. To better interrogate this connection, spatial transcriptomics has evolved to encompass a suite of new tools that have promised an unprecedented molecular description of whole tissue architecture. A breakout technique in this field is Multiplexed Error-Robust Fluorescence in situ Hybridization (MERFISH). MERFISH is an image-based single-cell transcriptomic tool that leverages optical barcodes to extend the scalability of traditional single-molecule FISH approaches to near transcriptome-level. MERFISH has been used to atlas a diverse range of cell types and states in the brain, liver, and gastrointestinal tract. However, as a probe-based approach, MERFISH was unable to distinguish between highly homologous gene targets such as the components of the B cell receptor, ultimately prohibiting MERFISH from tracking the interactions of specific B cell clones.
Here, I present a technical extension to MERFISH, hereby termed B Cell Receptor MERFISH (BCR-MERFISH), that equips the standard MERFISH measurement with the ability to assign clone IDs to plasma B cells. BCR-MERFISH uses an orthogonal optical barcoding set to detect and label IGHV, IGKV, IGLV, and Fc usage within single cells. Importantly, BCR-MERFISH is co-stainable with standard MERFISH libraries and places unique plasma B cell clones in their defined, native tissue contexts – allowing the user to identify key cellular interactions that occur between unique clones and their neighboring cells. I have validated the accuracy of BCR-MERFISH through transient transfections of specific IGHV and IGKV genes in HEK293 cells, a transgenic mouse with a biased expression of a known IGHV/IGKV pair, and by comparing its results to BCR-sequencing of matched ileal slices from wild-type mice.
I have used BCR-MERFISH in germ-free mice to reveal an enrichment of recurrent plasma cell clones within the lamina propria compared to that of specific pathogen-free mice – a phenomenon that was suggested by an enrichment of the same recurrent clonotypes found in the Peyer’s Patch germinal centers of germ-free mice.
I show that BCR-MERFISH can capture the spatial distribution of specific clones across both the mucosal and intestinal axes. Regarding the mucosa, the lamina propria of the villi recruits Ccr9+ plasma cells via the secretion of Ccl25. I demonstrate that in wild-type specific pathogen-free mice, that the distribution of unique plasma B cell clones is not dependent on the sequence of the BCR. However, despite the uniformity within the layers of the villus, certain plasma cell clones show significant enrichment within proximal, medial, and distal ileum. Furthermore, certain clones even exhibit a common co-occurrence with either their sisters or other specific plasma B cell clones. Together, I believe that BCR-MERFISH offers a path to many new insights into a wide range of immunological questions that require a more comprehensive description of the immune tissue environment compared to other existing technologies.Biological and Biomedical Science
From Temperature Extremes to Ocean Circulation: Insights from the Transport of Tracers
No full textTracers are ubiquitous in both the atmosphere and the ocean. This dissertation develops a tracer-transport-based perspective to provide a new quantitative toolbox and novel insights into two key problems in atmospheric and oceanic sciences.
The first problem concerns atmospheric temperature extremes (Chapter 1). By treating temperature as a tracer governed by its transport equation, I propose a new framework to quantify how different physical processes control the probability distribution functions (PDFs) of temperature at any given location. Using this framework, we find that horizontal temperature advection is the dominant control on local temperature extremes, governing extreme events over the mid-to-high-latitude oceans and approximately 60 % of the global land area. We further use this framework to decompose the contributions of different eddy and mean components of advection to the global distribution of temperature standard deviation and skewness. In particular, we show that the eddy-mean interaction term, v′ · ∇ T̄, makes a significant contribution to skewness—a contribution that has been largely overlooked in previous studies. This term highlights the potential amplification of temperature skewness due to changes in the waveness of atmospheric circulation and polar amplification. Finally, we briefly discuss the broader implications of this framework: it can be extended to understand the spatial distribution of other key tracers in the atmosphere and ocean, such as pollutants.
The second problem addresses the relationship between ocean circulation and the spatial distribution of ocean water age (Chapters 2 and 3). Starting from the age-tracer transport equation, I derive a conservation law for age: for any control volume, the total age flux across its boundary equals the volume of the control domain (Chapter 2). This conservation law allows us to infer diapycnal mixing and overturning circulation directly from the spatial distribution of age. Using a set of idealized single-basin MITgcm simulations, we demonstrate that the global overturning rate across different density levels can be quantitatively estimated from the age difference between upwelling and downwelling regions. We further show that this framework can be applied to regional ocean circulation. For example, by analyzing the zonal-mean vertical profile of age at the equator, we estimate the deep overturning rate in the North Pacific, yielding results consistent with previous studies.
This age framework is also applied to investigate the physical controls on the ventilation of mid-depth North Pacific waters—the oldest waters in the modern ocean (Chapter 3). We find that diapycnal mixing is the dominant control on ventilation in this region, while isopycnal mixing and overturning circulation play secondary roles. Based on this finding, we propose a method to estimate basin-scale effective diapycnal diffusivity from the vertical profile of horizontally averaged age. Applying this method to observational radiocarbon data, we obtain a bottom-enhanced diffusivity profile with magnitudes on the order of 10⁻⁴ m² s⁻¹, consistent with previous estimates. However, our inferred diffusivities are somewhat larger than those from state-of-the-art bottom-up estimates, highlighting the uncertainty in basin-scale diffusivity and the need for further investigation. The three applications of the age framework—global overturning, deep North Pacific circulation, and mid-depth North Pacific ventilation—demonstrate the potential of the age framework to enhance our understanding and quantification of past and present ocean circulation.Engineering and Applied Sciences - Engineering Science
Strange metal from metallic quantum phase transitions with spatial disorder
No full textPhysicsAuthor's Origina
Digital Influence Strategies in Information Warfare: A Multimodal, Cross-Platform Comparative Analysis of Russia Today and China Global Television Network
No full textNear-peer competitors like Russia and China have recognized the potential of social media as an asymmetric tool of influence in information warfare and a critical component of modern irregular warfare. Russia’s state-a liated global media outlets housed within RT (formerly Russia Today), which claim more than 10 billion YouTube views and 150 million monthly news network views, use coordinated account networks to amplify messaging and sow discord in target countries. China, which claims more than 150 million followers on CGTN (China Global Television Network) alone, strives to use Chinese state media to shape perceptions of China globally.
Recent multi-platform influence operations underscore the need for an urgent response. The Wagner Group, a Russian private military company, recently engaged in sophisticated disinformation campaigns across platforms like Facebook, YouTube, and Telegram. Leveraging paid influencers and bloggers, such efforts have been particularly active in shaping narratives, sowing discord, and advancing foreign geopolitical interests in Africa. Similarly, past reports highlight China’s coordinated dissemination of propaganda and disinformation through state-controlled media outlets and networks of inauthentic accounts. The complex challenges that multi-platform influence operations pose warrant a nuanced understanding of how they are designed, executed, and countered.
A multi-level analysis of the digital strategies of RT and CGTN across multiple social media platforms helps provide understanding and counter near-peer competitors in the information domain. Examining five years of content across various platforms, languages, modalities, targeted audiences, and audience interactions reveals how these states leverage asymmetric options in digital influence campaigns. Understanding applications of emerging technologies is crucial for the contribution of the U.S. Special Operations Forces (SOF) to win by exploring information warfare of near-peer competitors and developing effective counter-strategies against their strategic influence in the digital information space.Version of Recor