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The Experimental Space of the Diagram According to Peirce, Deleuze and Goodman: Concerning Composite Photography, Chronophotography, and Painting
No full textIn this article I examine the perspectives of Charles Sanders Peirce, Gilles Deleuze, and Nelson Goodman on diagrams in order to assess the variety of meanings of diagrammatic reasoning, form, and manipulation. I argue that diagrammatic reasoning may not only guide the understanding of the functioning of schemas, graphs, and chains of equations, but also—as I show in this article—the functioning of scientific images, photographs, and artistic paintings. More precisely, I focus on the relationship between the concept of diagram, the composite photographs by Francis Galton studied by Charles Sanders Peirce, works of art such as the paintings by Francis Bacon studied by Gilles Deleuze, and scientific images (especially aggregate images such as those of black holes), while taking account of the distinction between autographic and allographic semiotic systems
A Peircean Lens on Cinematic Special Effects
No full textThe aim of this paper is to reconsider how Peirce’s conceptions of iconicity and especially indexicality can help us logically account for some of the issues that pertain to representation in the cinema. To this end, the study centers on the practice of special effects as a way to reground the entire area of thinking about indexicality within the study of moving images. The author wishes to show how Peirce’s concepts not only remains viable for thinking about cinema but also offer a powerful tool for critically analyzing images
Food, Talk, and Knitting: Mutually Constitutive Elements in a Process of Adult Language Socialization
No full textLanguage socialization, the process by which individuals acquire identity markers associated with particular communities of practice, continues throughout life (Ochs 2000; Garrett and Baquedano-Lopez 2002); food often plays an important role creating environments where socialization can take place (e.g. Ochs and Shohet 2006). This paper considers the process by which some people, while learning to knit, are also socialized into identity as “knitter”, a process marked and facilitated by shared food consumption. Examining data gathered through participant-observation within two knitting groups, coupled with data drawn from a large on-line survey of the knitting community at large, I argue that food and language are mutually constitutive of the socialization experience for knitters, not simply due to co-occurrence, but because they indirectly index ideologies which underpin different knitting identities; that is, knitting and food are both semiotic resources in the expression of broader identities which have ideological and social coherence. Among some groups of knitters, this is a broader identity of service, sacrifice, and community building; among others, it is an identity associated with values of self-expression and feminism
Language and Territorialization: Food Consumption and the Creation of Urban Indigenous Space
No full textIn this paper we analyze two March 2010 events in Ottawa, Canada involving the preparation and consumption of seal-meat: one an Inuit seal feast, held at a Inuit community center, in which raw seal was carved and eaten in accordance with traditional Inuit practices; the other a “seal lunch”, held in the Parliamentary Dining Room for Members of Parliament, in support of the Canadian seal-hunt. Methodologically, we make use of both participatory action research and detailed textual analysis of media reports, and frame our analysis in terms of moral geographies, social and cultural values associated with food, and meaning-making systems embedded in discourses, which serve to construct and constitute particular power relations. Doing so leads us to claim that the two seal-meal events drew on and conveyed radically different meanings. The Inuit meal, though not overtly political, represented an act of food sovereignty and a claim to Inuit territoriality in the city. The Parliamentary seal lunch, by contrast, had a clear political aim, as a form of protest against the European Union decision to ban seal meat and other products. Yet, while purporting to support Inuit seal-hunting, the Parliamentary meal effectively communicated the utter foreignness of seal meat and Inuit foodways with respect to Western tastes and discourses about food and environmentalism—a fact that emerges through our ethnographic and media analysis of the two seal lunch events
On-Surface Dynamics Visualized via Supersonic Molecular Beam Scattering and Scanning Tunneling Microscopy
No full textOn-surface reaction dynamics play a critical role in chemical processes ranging from heterogeneous catalysis to the fabrication of semiconductors for electronic devices. Research presented in this thesis interrogates interfacial dynamics with angstrom-level resolution using an in situ scanning tunneling microscope in line with a supersonic molecular beam. A triply differentially pumped molecular beam line provides angle- and energy-selected gas molecules to access at times highly activated surface chemistry such as the dissociative adsorption of nitrogen on Ru(0001). Tight control of incident molecular kinetic energy and impinging angle paired with the ability to visualize the on-surface products of single molecule dissociation events provides previously unattainable insight into the energy dissipation channels governing reactivity in the N2/Ru(0001) system. Results demonstrate long-ranged non-thermal motion of N atoms following dissociation over a range of incident impact conditions. Next, nanolithography using a field emitting probe to dissociate CH species and localize oxygen atoms is revealed, promising the creation of nanopatterned 2D devices, quantum sensors, or next-generation catalysts using surface species as “atomic ink.” Growing graphene across the Ru(0001) surface produces a moiré patterned interface, and scattering ground state atomic oxygen reveals the role spin-flipping dynamics play in reactivity across monolayer versus bilayer graphene. Site-specificity and diffusivity of atomic oxygen on the moiré is shown to be coverage dependent with multiparticle interactions leading to correlated surface diffusion and higher surface mobility. The role of multiparticle interactions is again emphasized through co-deposition of buckminsterfullerene and atomic oxygen on moiré patterned graphene lending insight to thin film growth. Overall, results demonstrate a new direction in molecular scattering in which tight control of incident molecular kinematics is coupled with atomically resolved microscopy to probe on-surface dynamics
Working Together Apart: Culture, Conflict, and Teamwork in Chinese Professional Basketball
No full textThis dissertation investigates diversity and organizational performance through an indepth study of intrateam relationship and teamwork within a Chinese professional basketball club. I question why the club consistently failed to achieve coordinated and effective teamwork before and after the COVID-19 pandemic—but not during the pandemic, despite having highly skilled players from around the world, a collectivist organizational structure, and access to world-class resources. Drawing on 36 months of ethnographic research, over 190 interviews, and more than 600 hours of training and game footage, I demonstrate how distinct early training experiences shape players’ approaches to training, collaboration, competition, and rule interpretation. By comparing players from foreign private basketball academies with those trained in local Chinese programs, I show that interactions with coaches, teammates, competitors, and referees are shaped by and transmit the cultural contexts of players’ early training institutions. Compared to their locally trained counterparts, foreign and privileged Chinese players tended to approach opportunities and resources in training, collaboration, competition, and rule enforcement more proactively. These asymmetries in access and influence fostered persistent conflicts that ultimately undermined the club’s efforts to cultivate effective teamwork. While the culture-based explanation explained the struggle with teamwork before and after the pandemic, it does not answer why and how the team produced improved performance during the games in pandemic seasons. I find that a provisional organizational structure that I call “rotational scrimmage” enabled players from distinct class background overcome entrenched conflict during the process of training, collaboration, and competition. By introducing structured competition, rotational scrimmage promoted cross-class contact between previously antagonistic members and introduced competitions between players from the same class background. The scrimmages effectively weakened entrenched class-based xi conflicts, facilitating cross-class collaborations and fostering team synergy. In contrast, before and after the pandemic, an ordinary structure promoting a highly collectivist training regimen without rotational competition within teams led to failure when players from the same class background pursued their own goals at the expense of the goals of the players from different class contexts. Through four independent chapters with each addressing dynamics of training, collaboration, competition, and rule interpretation, this dissertation examines the dialectical relationship between transnational cultural economy and local production processes. Within each chapter, I show how the transnational flow of basketball talent to China transmits American cultural practices into local club operations, and clubs and players in rising powers like China simultaneously negotiate with and contest American cultural dominance in professional basketball. By tracing these interactions, the dissertation reveals how global cultural forces are both embedded within and transformed by local organizational practices
Molecular Basis of Diverse Gating Mechanism in Voltage-Gated Sodium and Potassium Channels
Get PDFThe action potential is the elementary unit for biological excitability in the animal kingdom. At the molecular level, voltage-gated ion channels underlie the action potential. Voltage-gated sodium (Nav) channels allow the influx of Na+ ions, initiating the depolarizing phase of the action potential and subsequently, voltage-gated potassium (Kv) channels carry the outward K+ current, restoring the membrane potential to the resting state. The precisely coordinated transitions among the conductive and nonconductive states of these ion channels give rise to the action potentials. From the broad hundreds-millisecond-long cardiac action potential to the fast action potentials in Purkinje neurons that subside within 10 milliseconds, the gating of the ion channels shape the action potentials and shape the physiology. All Nav and Kv channels possess an activation gate controlled by voltage. Upon depolarization, the voltage sensors in the channel activate and subsequently open the activation gate. However, the activation gate is not the only gate. In Nav channels, milliseconds after the opening of the activation gate, the fast inactivation gate closes, driving the channels into the nonconductive fast inactivated state. Contrary to the fast-acting fast inactivation gate in Nav channels, the slow inactivation gate in Kv channels closes over seconds or even tens of seconds. The various gates in the ion channels allow for the diverse behaviors of the ion channels and play fundamental roles in countless processes. This thesis aims to elucidate the molecular basis of the diverse gating mechanisms in Nav and Kv channels with a special emphasis on Nav channel fast inactivation. Utilizing electrophysiology, molecular dynamics, voltage clamp fluorimetry and single-particle cryo-EM, we provide mechanistic insights into fast inactivation mechanism in Nav channels and the activation/slow inactivation mechanisms in Kv channels
Cardiovascular Benefits of Reducing Household Air Pollution and Machine Learning-Based Approaches to Vascular Health Assessment in Low Resource Rural Settings
No full textCardiovascular disease (CVD) is the leading cause of premature morbidity and mortality worldwide, disproportionately affecting populations in low- and middle-income countries (LMICs) where household air pollution (HAP) from biomass fuel combustion remains a pervasive yet under-addressed environmental risk. Despite widespread recognition of the cardiopulmonary consequences of air pollution, the relationship between personal exposure to HAP and subclinical or preclinical markers of cardiovascular health is poorly characterized, particularly in LMICs. This dissertation investigates the cardiovascular health burden of HAP and the benefits of clean fuel intervention, while pioneering the application of machine learning for scalable vascular risk assessment in rural Bangladesh. Leveraging longitudinal data from the Bangladesh Global Environmental and Occupational Health (GEOHealth) Hub HAP study (2016–2021), which included 600 rural adults exposed predominantly to biomass fuel emissions, three interrelated research aims were pursued: (1) evaluating the associations of personal exposures (PM2.5, black carbon, carbon monoxide) with subclinical vascular and preclinical cardiovascular markers (carotid intima-media thickness (cIMT), brachial artery distensibility (BAD), and reactive hyperemia index (RHI)); (2) assessing the effects of a 26-month exclusive clean fuel (LPG) intervention on these endpoints among women; and (3) developing machine learning models, including convolutional neural networks, to predict BAD from carotid ultrasound images alongside clinical and sociodemographic variables. Cross-sectional analysis of baseline data revealed consistently adverse but modest (non-significant) associations between pollutant exposures and cIMT/BAD, while personal black carbon exposure was robustly (significant) linked to impaired endothelial function (RHI), underscoring the susceptibility of vascular endothelium to biomass combustion-derived pollution even in relatively healthy young adults. The clean fuel intervention achieved sustained reductions in key pollutant exposures but resulted in limited short-term improvement in subclinical vascular structures, while signs of functional vascular benefit suggest the importance of longer-term follow-up and multi-component risk mitigation strategies. Exposure-response analysis illuminated strong associations between cumulative particulate exposures and cIMT progression, supporting the biological plausibility of chronic air pollution as a modifiable driver of early vascular changes. Conventional cardiovascular risk factors (age, blood pressure, BMI) remained dominant determinants of vascular endpoints. Machine learning approaches demonstrated the technical feasibility of predicting BAD using combinations of clinical, sociodemographic, and CNN-extracted image features; however, clinical and sociodemographic markers explained most of the variance while imaging contributed incremental precision. This approach demonstrates the pragmatic utility of machine learning for scalable, non-invasive vascular risk stratification where direct testing is inaccessible. Collectively, these findings provide epidemiological, clinical, and methodological evidence supporting household air pollution reduction, especially targeting black carbon and PM2.5, as a viable public health strategy for early cardiovascular risk mitigation in LMIC populations. The dissertation underscores the imperative for multi-pronged intervention strategies, advanced analytic frameworks, and expanded application of machine learning-based assessment to address health inequities and inform policy for sustainable vascular health improvement in high-risk, under-resourced communities
Editorial: Unlocking the power of gut microbiota to improving health and welfare in non-ruminant livestock
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Random Regular Graph States Are Complex at Almost Any Depth
No full textGraph states are fundamental objects in the theory of quantum information due to their simple classical description and rich entanglement structure. They are also intimately related to instantaneous quantum polynomial-time (IQP) circuits, which have applications in quantum pseudorandomness and quantum advantage. For us, they are a toy model to understand the relation between circuit connectivity, entanglement structure, and computational complexity. In the worst case, a strict dichotomy in the computational universality of such graph states appears as a function of the degree of a regular graph state [Ghosh et al., Phys. Rev. Lett. 131, 030601 (2023)]. In this paper, we study the average-case complexity of simulating random graph states of varying degree when measured in random product bases and give distinct evidence that a similar complexity-theoretic dichotomy exists in the average case. Specifically, we consider random -regular graph states and prove three distinct results: First, we show two families of IQP circuits of depth and show that they anticoncentrate for any 2 1/2) when measured in a random - plane product basis. This implies anticoncentration for random constant-regular graph states. Second, in the regime =Θ() with ∈(0,1), we prove that random -regular graph states contain polynomially large grid graphs as induced subgraphs with high probability. This implies that they are universal resource states for measurement-based computation. Third, in the regime of high degree ( ∼/2), we show that random graph states are not sufficiently entangled to be trivially classically simulable, unlike Haar-random states. Proving the three results requires different techniques—the analysis of a classical statistical-mechanics model using Krawtchouck polynomials, graph-theoretic analysis using the switching method, and analysis of the ranks of submatrices of random adjacency matrices, respectively