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Connective tissue nevi: A case report of a uniquely presenting eyelid collagenoma
No full textPurpose: The purpose of this article is to report a unique clinical presentation of an eyelid collagenoma. Additionally, we review connective tissue nevi as a whole and describe the spectrum of collagenoma variants in relation to their specific syndromic associations. Observations: A 71-year-old female with a past medical history of cataract extraction, and remote amblyopia requiring patching presented to ophthalmology clinic with a chief complaint of an asymptomatic orbital lesion persistent over the last two years. Physical exam revealed a 0.5 cm tan-purple erythematous left upper eyelid papule with associated mild ipsilateral ptosis. Eye exam demonstrated 20/25 vision bilaterally. The patient opted for surgical excision of the lesion. Intraoperatively the lesion was found to be adherent to the overlying skin and underlying tarsal plate. Thus, the lesion was resected en bloc and required orbicularis muscle repair. Post-operative follow-up exam eight days after the initial procedure demonstrated a well-apposed linear scar site with minimal ecchymosis. The patient ultimately healed without complication. Based upon clinical features including shape, color, and external vascularity the lesion was initially favored to be a benign hemangioma. However, subsequent tissue diagnosis instead revealed the lesion to be a benign collagenoma. Conclusions and importance: While uncommon, benign connective tissue nevi including collagenomas can present as a single or rarely multiple facial lesion(s). Collagenomas can occur sporadically or as part of a genetic syndrome. Unique clinical presentations of collagenoma(s) may be a subtle indication of an underlying syndrome. Thus, the clinical features that are most important to assess on physical exam include the lesion focality (i.e., single vs. multi-focal), location of the lesion(s), and dermatologic configuration (i.e., papular or nodular vs. plaque-like vs. cerebriform etc.). Of note, while typically tan-pink in color on physical exam, collagenomas may be erythematous, as in our case, and can thus be mistaken for vascular lesions. Collagenomas are non-cystic in nature and thus from our experience do not appear to be amenable to surgical marsupialization. Lastly, if biopsy is pursued, an accurate diagnosis of collagenoma is important due to the aforementioned potential syndromic implications as well as a minimal though non-zero risk of recurrence.</p
High-resolution spectroscopy of barium monofluoride: Odd isotopologues, hyperfine structure, and isotope shifts
No full textBarium monofluoride (BaF) is a promising molecular species for precision tests of fundamental symmetries and interactions. We present a combined theoretical and experimental study of BaF spectra and isotope shifts, focusing in particular on the poorly understood odd isotopologues and . . By comparing state-of-the-art ab initio calculations with high-resolution fluorescence and absorption spectroscopy data, we provide a benchmark for electronic structure theory and disentangle the hyperfine and rovibrational spectra of the five most abundant isotopologues, from to . The comprehensive knowledge gained enables a King plot analysis of the isotope shifts that reveals the odd-even staggering of the barium nuclear charge radii. It also paths the way for improved laser cooling of rare BaF isotopologues and crucially supports future measurements of nuclear anapole and Schiff moments
Revisiting Ostension in Folkloristics
No full textSemiotic analysis in folkloristics usefully centers on iconicity, ostension, and indexicality as modes of representation active in performances of expressive culture. In this essay I focus on the semiotic mode of ostension, wherein a thing is used to represent itself, which I have found helpful in thinking about the efficacy of artistic performances at the heart of my ethnographic research over the years. Here I draw on my previous work with a child’s fantasy play and with verbal narrative performance to signal the enormous analytical potential that lurks in this somewhat neglected member of the triad. In both of these instances, the turn to ostension stands in contrast to the enveloping framework of iconicity, representation through likeness, a move, I contend, that opens possibilities for an epiphany, a transcending of normally discrete ontological sectors. I close the essay with a treatment of ostension in a ritual setting, the mesa or ritual table of an Andean day of the dead ceremony, where it works in tandem with iconic and indexical elements to create a dynamic model of the cosmos, but with the specific mission of fostering remarkable levels of immediacy
Specificity, length and luck drive gene rankings in association studies
No full textStandard genome-wide association studies (GWAS) and rare variant burden tests are essential tools for identifying trait-relevant genes. Although these methods are conceptually similar, by analysing association studies of 209 quantitative traits in the UK Biobank, we show that they systematically prioritize different genes. This raises the question of how genes should ideally be prioritized. We propose two prioritization criteria: (1) trait importance — how much a gene quantitatively affects a trait; and (2) trait specificity — the importance of a gene for the trait under study relative to its importance across all traits. We find that GWAS prioritize genes near trait-specific variants, whereas burden tests prioritize trait-specific genes. Because non-coding variants can be context specific, GWAS can prioritize highly pleiotropic genes, whereas burden tests generally cannot. Both study designs are also affected by distinct trait-irrelevant factors, complicating their interpretation. Our results illustrate that burden tests and GWAS reveal different aspects of trait biology and suggest ways to improve their interpretation and usage.</p
Ritual as Enunciative Praxis: Some Reflections for Kasuragi, Japan
No full textThis article uses the concept of enunciative praxis from Paris School semiotics, showing its possible intersections with Michael Silverstein’s idea of ritualization as “dynamic figuration,” and with other anthropological theories of ritual. I explore these intersections through an analysis of ritual action in a community of ascetic practice involved in the revival of the pilgrimage to the “Sutra Mounds of the Twenty-Eight Lodges of Katsuragi” (Katsuragi no nijūhasshuku kyōzuka), a mountain area in central Japan. Following these pilgrims, we ‘walk’ through different forms of ritualization, from an informal “interaction ritual” to a highly metricalized “full-tilt ritual,” passing through examples of ritual apprenticeship involving missteps and adjustment. I argue that the concepts of enunciation and enunciative praxis offer an accurate framework to describe the metapragmatic dynamics through which social roles are performatively redefined via verbal and nonverbal semiotic acts. Finally, by looking at the way notions of personhood, subjectivity, sacred language, and the cosmos are conceptualized by members of this ascetic group, I show how an impersonal and diagrammatic conception of enunciation—what I would like to call, after Marshall Sahlins, metapersonal enunciation—best fits the world-remaking rituals enacted by these ascetic practitioners
Images and/as Language in Nepal’s Older and Vulnerable Deaf Person’s Project
No full textDrawing on ethnographic research in Nepal’s Older and Vulnerable Deaf Person’s Project (ODP), this article explores the ways in which engagement with pictorial images in the ODP helped deaf elders cultivate the physical, semiotic, and pragmatic skills that underpin the reception and reproduction of conventionalized Nepali Sign Language (NSL) forms. This pedagogy emerged in part because local understandings of NSL as a named and objectified language have been grounded in pictorial illustrations of signers performing standardized lexical items in sign language dictionaries, posters, and primers. An analysis of an ODP session demonstrates how elders’ image-making practices in some cases worked to center their communicative practices on the standard lexical items in which local deaf sociality was grounded; in others cases it worked to exceed the relatively narrow view of NSL that these texts objectified. Analysis of these dynamics, along with my own use of pictorial images as a mode of generating, reflecting, and circulating analyses of language use, helps us consider the semiotic processes through which ideologies of image and language may be mutually constitutive, as well as how such a relationship can be regimented or unsettled
The Return of the Windigo, Again
No full textThis article continues the discussion of “And Some Guys Dream Bad Things” in this issue, an unreconstructed structural reading of the Algonquian windigo. Here, I take the occasion to reflect on what a specifically Peirce-inspired semiotic readings of windigo might consist of. A survivor of psychological anthropology (“culture bound syndromes”), functionalism, structuralism, cultural materialism, and even political economy, the windigo has yet to experience semiotic. I briefly introduce the two here, gesturing wildly in brief transit at a few among many possible sites of connection
Three Ways to Tame Structured Data
Get PDFThis dissertation presents three different problems in recovering underlying structure from data in diverse scientific fields, each also elucidating a different flavor of applied mathematical approaches. The first is a problem in manifold learning inspired by cryo-electron microscopy. We consider the problem of recovering a one-dimensional curve embedded in high dimensional space from a high noise observations centered around the curve. We prove a sample complexity lower bound to demonstrate an inherent difficulty in recovering the underlying curve from data, then provide an asymptotically optimal algorithm based on the method of moments. This work demonstrates how analytic and algebraic techniques can be applied to summary statistics to navigate the challenges of high dimensional, noisy data. The second problem we study is an optimal transport problem on discrete spin systems. We formulate a relaxation of the Glauber dynamics on the Ising model as an optimal transport problem in discrete time and space with an exponentially large number of variables. We then devise numerical techniques for tractably solving this algorithm at the scale of over one billion variables. This work highlights numerical and algorithmic approaches in applied mathematics. Finally, we move to the world of computational chemistry and develop a machine learning framework that simultaneously serves as a generative and foundational model for 3D conformers of small molecules. Our model is able to synthesize information across a large library of molecules and effectively learn what the manifold of plausible molecular conformers looks like, as well as learn mappings from conformers to molecular properties of interest. At the core of our method is a novel molecular representation that models conformers not as discrete point clouds but as dense fields. This work exemplifies the role of data-driven techniques in complex scientific domains. We hope this dissertation represents the rich diversity of domains and techniques in applied mathematics
A Psychedelic Reorientation to Death: Implications for how we attend to the fear and anxiety of death
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Tailoring Chloride Solid Electrolytes for Reversible Redox
Get PDFSolid-state electrolytes enable next-generation batteries that can theoretically deliver higher energy densities while improving device safety. However, when fabricating cathodes for all-solid-state batteries, solid-state electrolytes must be combined with the active materials in high weight fractions in order to achieve sufficient ionic percolation within the cathode composite. This requirement drastically hinders the practicality of solid-state batteries as the solid-state electrolyte is conventionally designed to be electrochemically inactive and is effectively electrochemical “dead weight”, lowering both the gravimetric and volumetric energy density of the cell. In this work, a well-known solid-state electrolyte, Na2ZrCl6, is modified by aliovalent substitution of inactive Zr4+ cations with redox-active M5+ (M = Nb or Ta) cations to create a series of Na2–xMxZr1–xCl6 solid solutions that possess both high ionic conductivities and active sites for Na+ storage. The Na+ intercalation mechanisms of these solid-solution materials, in addition to those of the NaMCl6 end-member materials, are elucidated in this work. It was discovered that both the niobium- and tantalum-containing chlorides exhibit rather high electrochemical potentials (2.2–2.8 V vs Na9Sn4), making them ideal catholytes to pair with commonly used oxide cathode materials like NaCrO2. This synergistic pairing leads to a cathode composite with an 83–102% increase in energy density and 39–81% improvement in areal discharge capacity compared to a redox-innocent solid electrolyte. This approach highlights the benefits of designing and employing redox-active solid-state electrolytes that can reversibly intercalate charge-carrying cations, opening up a broad new avenue for solid-state electrolyte discovery and solid-state battery design