Recent ucsc items

Cosmological Applications of Strong Gravitational Lensing

Fri, 11 Sep 2026 00:00:00 +0000

Strong gravitational lensing is poised to become one of the strongest probes of cosmology. Though rare, strong lensing is highly sensitive to the geometry of the universe and the distribution of mass in foreground galaxies or clusters. While strong lensing has long been used to study distant magnified objects, the past decade has seen rapid progress in applying SL to novel studies of dark matter and dark energy. I provide a survey of these possibilities, with a focus on studies of dark matter in lensing galaxy clusters. I present the most rigorous constraint to date on Self-Interacting Dark Matter (SIDM) at cluster scales, combining strong lensing with resolved stellar kinematics in lens system MACS J0138-2155. Additionally, I discuss a powerful possibility for constraining the dark energy equation of state with strong lensing, a technique known as compound lens cosmography, and encouraging results with a remarkable lens system known as the Carousel Lens.

Is Your VPN Getting You Blocked?

Fri, 11 Sep 2026 00:00:00 +0000

There are many valid reasons for someone to browse the internet privately, and Virtual Private Networks (VPNs) are one method of achieving this. Although primarily used to provide confidentiality and anonymity by encrypting internet traffic and masking IP addresses, users may choose to use a VPN for multiple purposes. However, this raises questions about whether, and how differently, content across the internet is portrayed to VPN users. VPN providers do not all route their traffic the same way, and this study analyzes these differences by investigating two major VPN providers, NordVPN and Surfshark. We measure and quantify the accessibility of popular websites to users of these two VPNs, comparing outcomes against a non-VPN control connection to determine whether, and to what extent, VPN use affects a user's ability to reach and use ordinary websites. This raises a central question: is VPN-related blocking better explained by the network a VPN happens to use, or by...

Advancing quantitative fatty acid signature analysis (QFASA) for cetacean diet estimation: Methodological evaluation and ecological application

Fri, 11 Sep 2026 00:00:00 +0000

Quantifying cetacean diet is critical for understanding ecological and physiological processes but remains inherently challenging. Quantitative fatty acid signature analysis (QFASA) is a diet determination method with the potential to generate detailed, long-term diet estimates, but its use in cetaceans has been limited. My dissertation presents the first application of QFASA in bottlenose dolphins (Tursiops truncatus, hereafter “dolphins”). It addresses key impediments to QFASA’s broader application in cetaceans, evaluates its performance in professional-care and free-ranging dolphins, compares it to other diet determination methods, and explores the estimates’ ecological implications. In Chapter 1, I used dolphins under professional care with known diets to derive calibration coefficients (CCs) and explore the temporal integration period of blubber fatty acids. I found that dolphin- and blubber layer-specific CCs produced lower-error estimates and identified major prey more...

Network Load Balancing For Geographically Distributed Datacenters

Fri, 11 Sep 2026 00:00:00 +0000

As datacenters scale up and become more geographically distributed, wide-area network inter-datacenter traffic, which typically consists of data-heavy tasks, has become increasingly prevalent. Some of the noteworthy challenges raised by the coexistence and interaction between inter- and intra-datacenter traffic are the differences in their QoS requirements, link utilization, and round-trip times. To the best of our knowledge, these challenges have not yet been addressed by current datacenter load balancers. To highlight this gap, we conducted a comparative performance study of state-of-the-art datacenter load balancers. Through extensive simulations, we study how they perform under different network topologies and workloads, including intra-datacenter, inter-datacenter, and mixed intra- and inter-datacenter workloads that reflect how datacenters have evolved to keep up with their continuously changing driving application landscape. Our study shows that current load balancers are...

Black Holes as Precision Probes of Dark Sectors and Fundamental Physics

Fri, 11 Sep 2026 00:00:00 +0000

This thesis investigates the observational and phenomenological consequences of large gravitationally coupled dark sectors, using black holes and high-frequency gravitational waves as the primary probes. The work spans four interconnected studies, progressing from broad model-independent constraints on dark sector size, through the physics of primordial black holes as a dark matter candidate, to a detailed reexamination of black hole evaporation dynamics, and culminating in a quantitative assessment of high-frequency gravitational-wave signals from superradiant boson clouds. The first study derives comprehensive constraints on the number of dark degrees of freedom N from multiple astrophysical and collider observables. Hawking evaporation of stellar-mass black holes observed by LIGO/Virgo provides the dominant bound: using the merger event GW190924 021846, with chirp mass 5.7 M⊙ and inferred age (1.16±0.04)×1010 yr, we constrain N ≲ 5×1058 for massless spin-0 dark sectors...

Modified Mean Curvature Flow in Fuchsian Manifolds

Fri, 11 Sep 2026 00:00:00 +0000

The equidistant surfaces in a Fuchsian manifold form a canonical foliation by constant mean curvature surfaces. It is therefore natural to ask whether a prescribed leaf of this foliation can be reached by evolving an arbitrary graphical surface. We answer this question affirmatively using the modified mean curvature flow. Let (M³, ḡ)=(ℝ×Σ, dr²+cosh²(r)g₀) be a Fuchsian manifold, where (Σ,g₀) is a closed hyperbolic surface. For any σ∈(−2, 2), we consider the flow ??/??=−(?−?)? starting from an arbitrary smooth closed geodesic graph over the central totally geodesic surface. We prove that the flow exists smoothly for all time, remains graphical, and converges smoothly to the unique equidistant surface Σ(?_?), where ?_?=arctanh(?/2) whose mean curvature is ?. The initial graph is required only to be strictly graphical; no smallness assumption or quantitative angle–height pinching condition is imposed. The main difficulty is that strict graphicality alone does not provide...

Barcode Growth for Toric Domains

Fri, 11 Sep 2026 00:00:00 +0000

In this thesis, we study barcode growth functions of the symplectic homology of Liouville domains. We show that the barcode growth function of a smooth convex/concave or real analytic toric domain grows at most like a polynomial of degree half the dimension of the domain. In particular, the barcode entropy of such a domain is zero and its slow barcode entropy is bounded by half the dimension, reflecting the complete integrability of the Reeb flow on the boundary. We extend the definition of barcode growth functions to star-shaped domains with non-smooth boundary via smooth approximations in the symplectic Banach–Mazur distance, and show that the polynomial bound persists for non-smooth convex/concave toric domains. We also show that barcode entropy and slow barcode entropy are invariants of the exact symplectomorphism type of the interior. As applications, we obtain obstructions to exact symplectomorphisms between interiors of Liouville domains.

Finding Freedom in the Post-Utopian Ruins: Li Xiaojiang’s 40 Years of Women’s Thought

Fri, 11 Sep 2026 00:00:00 +0000

This dissertation investigates works of Li Xiaojiang (1951-2025), a foundational figure in the development of women’s studies in post-socialist China who received comparatively little attention in international scholarship. Li has been criticized for essentialist understanding of sex and gender and for advocating women’s self-improvement in ways that appeared complicit with China’s state-led modernization and emerging market economy. Without dismissing these criticism, this dissertation argues that they capture only part of Li’s theoretical and political significance. Reading her work across four decades, I recover a sustained concern with a fundamental political question: how might women cultivate subjective capacity and political agency under conditions that seem to leave little for either? The dissertation traces Li thought roughly chronologically. I first examine her writings of the 1980s for which she received the most criticism for. Drawing on the body of texts that...

Ranked Enumeration over Circuits via Implicit Representations

Fri, 11 Sep 2026 00:00:00 +0000

We study the problem of enumerating the satisfying assignments of smooth multivalued d-DNNF circuits in sum order. We measure the cost in terms of a preprocessing phase and the delay between consecutive answers, charging for both the size of the circuit and the number of variables. Producing each answer as a complete assignment takes time linear in the number of variables. We propose an algorithmic framework that avoids this cost by producing answers in an implicit representation. After preprocessing quasilinear in the size of the circuit, the delay for tree-shaped circuits is logarithmic in the number of answers already produced and independent of the number of variables. For general circuits, preprocessing incurs an additional factor of the number of variables, and one further term remains in the delay, logarithmic in the number of variables. An answer can be recovered explicitly from its implicit representation in additional linear time.

Centering Healing, Countering Denial: Journeys Toward Racial Healing in Black Communities and Uncovering White People's Denial of Black Racial Trauma

Fri, 11 Sep 2026 00:00:00 +0000

Racial trauma (i.e., trauma resulting from racist experiences) is a persistent and harmful psychological consequence of racism, yet it is denied or minimized by dominant cultural narratives and ideologies. The current work explores how Black communities can heal from racial trauma and how racial trauma is perceived in White communities. Study 1 examines Black community healing from intergenerational racial trauma, using secondary analysis of interviews with Black participants who visited key historical sites from the transatlantic slave trade in Ghana, West Africa. I employed an integrative methodological framework rooted in Black epistemologies, including the methodology of surrender, the daughtering method, and the H.U.N.C.H. method. Findings illuminate how place-based, community-centered, and ancestrally grounded experiences can facilitate healing from intergenerational racial trauma. Study 2 examined how White participants perceive racial trauma, exploring how different levels...

Writing Music to Fit: The Place of Music in South Korean Ch'angjak Musicals

Fri, 11 Sep 2026 00:00:00 +0000

This dissertation examines how the secondary position of music to drama in South Korean ch'angjak musicals (창작뮤지컬, originally created musical theater) has been historically and structurally established. Integrating archival research, score analysis, and ethnographic fieldwork in the Taehangno theater district of Seoul, it argues that the genre's production mechanisms, its development processes, the curricula that train its practitioners, and the conventions of its criticism and audience feedback are all organized with dramatic considerations taking priority.The musicians in ch'angjak musicals often experience frustration at this secondary position, and at having musical judgments that diverge from those around them. This dissertation, however, does not read this as a musical deficiency of the genre. Rather, it demonstrates that the resulting sound reflects a negotiation among differently formed musicalities—that of the music team, shaped by musical training, and that of the writers,...

Multiwavelength Modeling of the Blazar 1ES 0647+250 and the Impact of Cosmic Voids on the High-Energy Detection of Active Galactic Nuclei

Fri, 11 Sep 2026 00:00:00 +0000

Multiwavelength spectra of active galactic nuclei (AGN) are affected by intrinsic AGN emission mechanisms fueled by the source environment and cosmic propagation along our line of sight (LoS), neither of which is fully understood. This thesis explores the former through multiwavelength data analysis and modeling of a particular blazar using a synchrotron-self-Compton model, and the latter specifically LoS effects due to photon-induced electromagnetic cascades developing in and out of cosmic voids through simulations of energetic (E> 100 MeV) photon propagation over cosmological distances.Three very high-energy (E > 100 GeV) states of the distant (20.45±0.10) blazar 1ES 0647+250 observed by the Very Energetic Radiation Imaging Telescope Array System are identified, and the emission zone is modeled using a leptonic synchrotron-self-Compton and blob-in-jet framework. It is found that one of the simplest scenarios that can describe the multiwavelength properties of the three...

Circularly Symmetric Disks Whose Transport Twistor Spaces Admit Global Blow-Down Maps

Fri, 11 Sep 2026 00:00:00 +0000

In the literature on X-ray transform and Transport Twistor (TT) space, blow-down maps describe the degeneracy of the TT space of an oriented Riemannian surface, while collapsing (yet separating) geodesics of the unit tangent bundle of that surface. In the literature [3], such maps have been constructed for simple surfaces of near-constant curvature (see Definition 1.1), showing that the interior of their TT space is biholomorphic to an open set in standard C 2 . The construction there relied on a microlocal argument leveraging the absence of conjugate points.In this dissertation, we construct explicit circularly symmetric examples, including examples with conjugate points, whose transport twistor spaces admit a global blow-down map.

Base-level lowering rates control a landslide process transition in California's Franciscan mélange

Fri, 11 Sep 2026 00:00:00 +0000

California’s Franciscan mélange is well-known for hosting persistent, slow-moving earthflows, a landslide style favored by the unit’s significant local variability in shear strength (e.g. Medley, 2001; Kim et al., 2004; Roering et al., 2015). Big Sur’s mélange, however, is unusual: landslide mapping there reveals both recent (e.g. the 2017 Mud Creek landslide) and prehistoric rotational landslides on slopes that are unusually steep for this lithology. Because rotational landslides and earthflows pose markedly different hazards, understanding what drives the shift in failure style is critical for hazard assessment. Here we test the hypothesis that the rate of base-level lowering governs the transition between earthflow and rotational failure. We synthesize landslide mapping and analysis of high-resolution topography across two Franciscan mélange settings with contrasting rates of base-level lowering: the South Fork Eel River canyon, where river incision drives base-level lowering...

Genomic Conflicts Across Evolutionary Scales

Fri, 11 Sep 2026 00:00:00 +0000

Genomic conflict arises when genetic elements increase their own proliferation despite imposing costs on their hosts. This dissertation examines how these conflicts emerge, persist, and reshape genomes across evolutionary timescales through three studies integrating gamete sequencing, comparative transcriptomics, long-read isoform sequencing, and population genomics. First, I investigated pollen-acting segregation distortion in crosses within and between Arabidopsis lyrata and A. halleri populations. Distortion was absent from crosses between closely related parents but widespread and variable in more divergent crosses, including crosses within species. Repeated, opposing distortions across chromosomes and genome-wide non-independence among loci were more consistent with negative epistatic incompatibilities than with independent single-locus drivers, demonstrating that reproductive barriers can arise early during population divergence. Second, I examined transcript processing...

Expert-Guided Integration of Raman Spectroscopy, X-Ray Diffraction, and Machine Learning for Mineralogical Interpretation of Mars-Relevant Materials

Fri, 11 Sep 2026 00:00:00 +0000

Planetary exploration requires extracting physically meaningful information from incomplete measurements acquired under environmental, instrumental, and operational constraints. This dissertation integrates Raman spectroscopy, X-ray diffraction (XRD), mineral physics, and computational analysis to expand the information recoverable from measurements of Mars-relevant materials. Raman spectroscopy provides the central connection among these studies because its vibrational frequencies, intensities, and spectral shapes encode not only mineral identity, but also bonding, hydration, crystallinity, temperature, structural disorder, and crystallographic orientation. Three studies progressively examine mineral phase identification, mineral physical state, and how it is crystallographically organized. A convolutional neural network trained using high-volume, wide within-class Raman datasets and demonstrated robust mineral classification under dusty, low-signal, and otherwise nonideal conditions...

SORh: Hyperbolic Relaxation Methods For Elliptic Problems In Computational Fluid Dynamics

Fri, 11 Sep 2026 00:00:00 +0000

This thesis investigates iterative methods for solving elliptic partial differential equations (PDEs) in computational fluid dynamics (CFD), with particular emphasis on self-gravity modeled by Poisson’s equation. Available solution strategies—including direct factorizations, FFT-based methods, multigrid, and classical relaxation schemes—offer different balances among computational cost, scalability, implementation complexity, and adaptability to changing boundaries and mesh structures. In this work, we examine how hyperbolic pseudo-time dynamics can be used to balance these considerations while providing a simple, local route to an elliptic steady state.To explore this question, we develop SORh, a relaxation framework derived from a hyperbolic pseudo-time reformulation of elliptic equations. Its linear discretization belongs to the established accelerated over-relaxation (AOR) family and reduces exactly to classical successive over-relaxation (SOR) at unit CFL. The derivation...

Essays in Development and Environmental Economics

Fri, 11 Sep 2026 00:00:00 +0000

This dissertation examines how public policy and infrastructure shape environmental quality, local economic activity, governance, and health. Across three chapters, it combines spatial data, village-level survey evidence, and quasi-experimental research designs to study the effects of environmental and infrastructure policies in Indonesia and India. The first chapter studies the environmental consequences of China’s 2018 National Sword policy, which restricted waste imports and redirected large volumes of plastic waste toward Southeast Asia. Global plastic waste generation has increased significantly over the past two decades, while recycling rates have remained low, and high-income countries continue to export low-quality waste to countries with limited processing capacity. Using spatial and temporal variation in exposure to waste pollution, this chapter estimates the causal effect of increased plastic inflows on fine particulate matter (PM2.5) across Indonesia. The analysis...

Advanced Electrode Design for High-Rate Alkaline Water Splitting

Fri, 11 Sep 2026 00:00:00 +0000

Electrochemical water splitting provides promising technology for green hydrogen production. Among different electrolysis technologies, alkaline water splitting is attractive because it can use earth-abundant electrode materials and relatively low-cost materials. However, efficient operation at industrially relevant current densities remains challenging due to gas bubble accumulation, ion-transport resistance, sluggish anodic kinetics. These limitations become more severe under high-rate conditions, where rapid gas generation and fast ionic consumption can reduce electrode-electrolyte contact and increase the overall cell voltage.This dissertation focuses on advanced electrode design and interfacial engineering strategies to address these challenges. First, nickel nanocone-modified surfaces were developed to improve gas bubble detachment. The nanocone structures created a superaerophobic interface, leading to shorter bubble residence times and smaller bubble detachment sizes during...

Geospatial Optimization of California's Organic Waste Diversion System: Transportation, Compliance, and Infrastructure Planning

Fri, 11 Sep 2026 00:00:00 +0000

Organic materials decomposing in landfills generate methane, making landfills a major anthropogenic methane source in the United States. Methane has a warming effect approximately 86 times greater than carbon dioxide on a per-mass basis over a 20-year horizon. California has responded with Senate Bill 1383 (SB 1383), which requires a 75% reduction in organic waste disposal relative to 2014 levels. Composting is a major pathway for achieving this goal while producing a soil amendment that can improve soil properties and promote soil carbon storage. Yet California’s existing composting system processes only about 6.5 million metric tons (MMT) of organic material annually, compared with approximately 14.3 MMT that must be diverted, creating substantial spatial, regulatory, and infrastructure challenges.This dissertation develops statewide geospatial optimization frameworks integrating 447 waste-generating jurisdictions, approximately 200 existing composting facilities, more than...

Report on the Replication of Shinn & Blumstein (1984)

Fri, 11 Sep 2026 00:00:00 +0000

This study examines how American English listeners use two temporal parameters, amplitude rise time (ART) and transition duration (TD), to diagnose consonant manner, replicating previous work on the /b/-/w/ contrast (Shinn & Blumstein, 1984). A tripartite free response pattern is found, replicating stop and approximant responses at fast-ART, fast-TD, and slow-ART, slow-TD regions of the stimulus space, respectively, and replicating critical fricative responses in the slow-ART, fast-TD region of the stimulus space. This confirms that listeners do not require frication to report hearing fricatives. However, likely due to changes in synthesis parameters, we fail to replicate the original categorization responses, and find approximant responses in the fast-ART, slow-TD region of the stimulus space, akin to the results of Walsh & Diehl (1991), where the original experiment finds stop responses. Taken together, these results present a complex –if early– picture about the role...

Characterizing Endocrine Variation in North Pacific Humpback Whales: A Blubber-Based Investigation Across Physiological and Behavioral Contexts

Fri, 11 Sep 2026 00:00:00 +0000

Hormones provide a direct measure of the physiological state of wild animals. Yet, the natural variation that underlies endocrine biomarkers remains poorly characterized in North Pacific humpback whales (Megaptera novaeangliae), a population recovering from commercial whaling while facing increasingly variable ocean conditions. In this dissertation, I characterized variation in reproductive steroids and glucocorticoids measured from minimally invasive skin–blubber biopsies collected on the Hawaiʻi breeding grounds (2014–2025) and the Southeast Alaska feeding grounds (2023–2025), spanning sex, reproductive class, season, social context, and region.In male humpback whales (Chapter 1), androgens and progesterone were elevated on the breeding grounds, and androgens declined across the breeding season, consistent with males arriving in a heightened reproductive state and exhibiting reduced androgen production as the breeding season progressed. Reproductive hormone profiles did not...

Scalabe Phylo-Pangenomics

Fri, 11 Sep 2026 00:00:00 +0000

The COVID-19 pandemic generated genomic data at unprecedented scale, with tens of millions of SARS-CoV-2 genomes deposited in public repositories and thousands of new sequences added each day. This dissertation develops methods for analyzing genomic datasets at this scale, unified by the idea that encoding genomes according to their evolutionary relationships can make otherwise intractable computations practical. First, I evaluate online phylogenetic inference, in which new genomes are continuously added to an existing tree, and compare parsimony-based methods with maximum-likelihood approaches under pandemic time constraints. For densely sampled SARS-CoV-2 genomes, online inference with UShER and matOptimize produces trees comparable to established maximum-likelihood methods while requiring orders of magnitude less time and memory. I then develop tools that make phylogenies containing millions of genomes useful for downstream analysis and visualization. ShUShER enables privacy-preserving...

Toward Sustainable and Secure Open Source Software: Discovery, Measurement, and Defense

Fri, 11 Sep 2026 00:00:00 +0000

In March 2024, a backdoor was discovered in xz Utils, a widely-used open source data compression library present in nearly every major Linux distribution. The attack was discovered days before merging into major distributions, and if this had happened, it would have allowed attackers to execute arbitrary code on millions of systems worldwide via SSH.The success of this backdoor was enabled by two failures. The first was technical: weaknesses in the software supply chain allowed a malicious actor to inject code into a widely trusted release. The second was human: the project's only maintainer, overwhelmed and burned out after years of maintaining critical infrastructure alone, was the target of a multi-year social engineering campaign, in which a malicious actor built trust under a false identity and gradually obtained commit access to the project. This incident shows that software security failures and sustainability failures are not independent: an overburdened, unsupported maintainer...

Learned Gridless Representations of Cone Beam Computed Tomography Scans

Fri, 11 Sep 2026 00:00:00 +0000

Medical image representation has long been dominated by voxel-grid matrices. While their inherent structure and order work efficiently for various linear transformations and provide a seamless visualization method on monitors, they fail to preserve the topology of the scan and to encode sparse information in a memory-efficient way.The recent emergence of machine learning-based continuous coordinate-based scene representations such as neural radiance fields and Gaussian splatting has provided alternative representation techniques. These approaches overfit the weights of a model by iterative differentiable rendering and have been shown to be more compact than grid representations. Moreover, they are then able to perform novel view synthesis from any given camera pose.Off-grid representations translate directly to Cone Beam Computed Tomography sparse-view acquisitions, where streaking and quantum noise artifacts are dominant. Using differentiable rendering, a continuous representation...

Éclater le langage : translation, resistance, and the lesbian and feminist network of Montreal

Fri, 11 Sep 2026 00:00:00 +0000

This dissertation explores writing and translation as modes through which to interpret problematics of language and gender in literature. In relation to the community I study, translating and writing are not separate gestures, but rather two vital pieces of a queer, feminist ontology that resists hierarchies and binaries within language. I examine the practice of writing-translation in a group of women living and working in Montreal during the 1980s and 90s—the Montreal lesbian feminist network. This period, together with the physical space of urban Montreal and its radical history, influenced the experimental art produced. During this time, Montreal served as a central meeting place for lesbian and feminist writers, poets, artists, literary translators, and performers from Anglophone and Francophone backgrounds. Though incredibly diverse in their experiences and histories, these women shared a common interest in expressing anti-hierarchical perspectives on gender, sexuality,...

First-Generation Latina Graduate Students Engaging Conocimiento Across Contradictory Expectations in Their Academic and Home Worlds

Fri, 11 Sep 2026 00:00:00 +0000

First-generation Latina graduate students navigate multiple and often contradictory expectations and experiences across different settings (e.g., academia, home life). For example, while graduate education can create opportunities for professional growth and future possibilities, it can also position students within settings that privilege dominant ways of knowing and being while devaluing their own cultural knowledge, familial relationships, and lived experiences. These contradictory experiences can create tight spaces that foster emotional turmoil and fragmentation while also creating opportunities for reflection and transformation. To understand these experiences, I draw from Gloria Anzaldúa's (1987) Borderlands theory, which examines how individuals navigate multiple, often contradictory social, cultural, and political worlds. Anzaldúa also theorizes that through the seven-stage process of conocimiento, individuals critically make meaning of these contradictions, ultimately...

Territorial Discipline: Unsettling Histories of the Land-Grant College System

Fri, 11 Sep 2026 00:00:00 +0000

What does it mean to take the dispossession of Indigenous land as central to the history of American higher education? This dissertation examines the history and context of the 1862 Morrill Land-Grant Act to pose a theorization of the land-grant college system as a critical site of settler-colonial dispossession. Looking at the problem and process of the material basis of disciplinary formation and institution building, this inquiry is organized along three lines of flight. First, how does the land-grant university produce institutional history that crops out its dispossessive conditions of possibility? I examine the university archives of Pennsylvania State University and Michigan State University alongside genres of commemoration and memorialization to position the production of forgetting as a key feature of the settler-colonial university. Secondly, how have Indigenous modes of agriculture been delegitimized and displaced through the disciplinary formation of scientific agriculture?...

Grounding with Agents

Fri, 11 Sep 2026 00:00:00 +0000

In my dissertation I investigated how we expect artificial agents (e.g., chatbots, voice assistants, robots) to ground with people. I focused on two aspects of grounding: (a) how people interpret errors from an agent and (b) how people expect agents to contribute to resolving errors in communication. Two experiments inform how we expect technology to engage in navigating grounding in a conversation. Additionally, these experiments offer insight into how similarly we want technology to mimic human speech behaviors or if we have differing expectations for how technology should communicate.Experiment 1 uses a Wizard of Oz (WOz) design where a voice assistant (VA), in this case an Alexa, commits phoneme level speech errors (swaps, anticipations, and perseverations) across three between-subjects conditions: (1) no errors (no speech errors committed), (2) errors (speech errors are committed), and (3) errors with correction (speech errors are committed and immediately self-corrected...

Carboxyhemoglobin and depletion of blood oxygen in sleeping elephant seals

Fri, 11 Sep 2026 00:00:00 +0000

An exceptionally large blood O2 store underlies the remarkable dive performance of elephant seals. However, elevated carboxyhemoglobin (COHb) concentrations in these seals complicate estimations of blood O2 content and O2 depletion rates, and may also affect monitoring of brain oxygenation in seals with new non-invasive near-infrared (NIR) recorders. Using hemoximetry analyses of blood samples during sleep apneas of juvenile northern elephant seals (Mirounga angustirostris), we constructed in vivo Hill plot equations and O2–Hb dissociation curves (ODCs). We found: (a) COHb and methemoglobin (both of which do not bind O2 and increase hemoglobin (Hb) affinity for O2) comprised 8% of Hb, (b) an in vivo P50 (partial pressure of O2 at 50% Hb saturation, an index of O2 affinity of Hb) of 27.1 mm Hg that was Hg 3.4 mm Hg less than that previously determined with an in vitro laboratory approach, and (c) when the in vivo and in vitro Hill plot equations were applied to arterial,...

Environmental Consequences in Coastal Wetland Following World’s largest Lithium-Ion Battery Storage Facility Fire: Vegetation and Soil Influences

Fri, 11 Sep 2026 00:00:00 +0000

On January 16, 2025, a major fire occurred at the Moss Landing Power Plant Facility located adjacent to the Elkhorn Slough, one of the largest remaining coastal wetlands in California. The fire burned 3 days becoming the largest battery-facility fire in the world to date. Lithium-ion battery fires potentially pose a risk to human and ecological health, as they can release trace metals, specifically: nickel, manganese, and cobalt that can be dangerous when surpassing safety exposure limits (Pennington, 2025). As societies shift towards alternative energy formats, there is a greater demand for battery energy storage infrastructure; however, these infrastructures carry risks. This study aimed to extend initial post-fire assessments by examining long-term effects of trace metal release and metal transport pathways. Sediment samples and random quadrat vegetation surveys were collected from 2 marsh sites, in the Elkhorn Slough. Samples were analyzed utilizing field portable X-ray fluorescence...

Potential and evidence for local adaptation in corals

Fri, 11 Sep 2026 00:00:00 +0000

Climate change poses an existential threat to tropical corals, but corals vary in their thermal tolerance at multiple spatial scales. Here, I evaluate the spatial scales at which corals show potential and evidence for local temperature adaptation.In Chapter 1, I evaluate the scale at which microclimates are detectable by comparing remotely sensed sea surface temperatures to data from in situ temperature loggers on reefs worldwide. I found that the remote dataset constitutes a good proxy for maximum monthly mean temperatures, but missed sub-daily variation as well as peak temperatures in the hottest microclimates. In Chapter 2, I used Acropora tenuis samples from the Philippines to evaluate isolation by distance patterns in both coral hosts and their algal symbionts. I found four near-panmictic taxa within our Acropora cf. tenuis samples, consistent with long (20km+) larval dispersal distances, but significant spatial structuring in their symbiotic algae. In Chapter 3, I looked...

Antibodies, Diet, and the Microbiota: Bacterial-Dependent Induction of Anti-Fiber Antibodies and How They Influence Microbial Biology

Fri, 11 Sep 2026 00:00:00 +0000

Protein and glycan antigens synthesized by gut microbes stimulate circulating and secreted antibody production. Despite continuous exposure of hosts to the plant glycans that constitute dietary fiber, it remains unclear whether these foreign structures induce mucosal immune responses. We report that humans and mice generate antibodies specific for common glycans in plant foods. Oral exposure to individual fiber types induced T cell-independent, glycan-specific IgM and IgA. The induction of anti-fiber antibodies required colonization by particular microbes, since germ-free mice and mice harboring representatives of several bacterial phyla failed to respond. The OMM12 model community was sufficient to rescue antibody induction, and dietary fiber glycans were detected on the surfaces of OMM12 microbes, suggesting a route by which bacteria trigger anti-fiber immune responses. Our results reveal a direct impact of dietary fiber on the adaptive immune system with implications for host...

Rational Design of Nanomaterials for Electrocatalytic Reactions

Fri, 11 Sep 2026 00:00:00 +0000

Electrochemical water splitting is widely recognized as a promising strategy for sustainable hydrogen production, where the development of efficient, stable, and cost-effective electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is of critical importance. Among various transition metal catalysts, ruthenium (Ru)-based materials have attracted significant attention due to their remarkable catalytic activity, tunable electronic structure, and relatively lower cost compared to platinum-group metals such as Pt and Ir. However, challenges remain in optimizing Ru utilization efficiency, regulating its electronic configuration, and achieving rapid and scalable synthesis of high-performance bifunctional catalysts. This dissertation focuses on the rational design, rapid synthesis, and mechanistic understanding of Ru-based nanostructured electrocatalysts for efficient electrochemical water splitting. Chapter 1 introduces the fundamental principles...

Bayesian Modeling and Scalable Inference for Count Time Series in Infectious Disease Surveillance

Fri, 11 Sep 2026 00:00:00 +0000

Real-time monitoring of infectious disease outbreaks calls for statistical models that recover interpretable quantities such as the time-varying reproduction number from noisy count data, track posterior uncertainty, and run on time scales compatible with daily updates. Existing methods address these aims through separate model classes. Discrete-time Hawkes-type models, Poisson autoregressions, and distributed lag models each capture self-exciting transmission through alternative parameterizations of the same conditional mean structure, but they have been developed across separate software packages with model-specific inference routines, which makes structural model comparison cumbersome in practice. This dissertation develops a unified Bayesian framework for count time series in disease surveillance, organized around three threads. First, a class of dynamic generalized transfer function models places the three modeling families inside a common modular state-space class built...

Essays in Macroeconomics: Measuring Economic Slack in Labor Markets and Business Cycles

Fri, 11 Sep 2026 00:00:00 +0000

This dissertation consists of three essays in macroeconomics. The first essay examines labor-market efficiency by incorporating part-time employment. The second and third essays study real-time recession detection, using labor market data in Japan and real-time GDP data in the United States. Chapter 1 extends the sufficient-statistics formula for efficient unemployment developed by Michaillat and Saez (2021a) to account for part-time employment. I introduce two additional sufficient statistics that measure the share of part-time employment and part-time hours relative to full-time hours. Applying the framework to the United States (1951–2026) and Japan (1970–2025), I compare the effects of total part-time employment and involuntary part-time employment on efficient unemployment. Total part-time employment has substantially larger effects than involuntary part-time employment. While involuntary part-time employment provides information about labor-market slack, the main change...

Genetic Determinants of Antimicrobial Peptide Responses in Vibrio cholerae

Fri, 11 Sep 2026 00:00:00 +0000

Cationic antimicrobial peptides (CAMPs) are key components of innate immunity that provide defense against bacterial pathogens. Vibrio cholerae, the causative agent of cholera, colonizes the small intestine, where it encounters CAMPs produced by the host epithelium. Although several CAMP-responsive pathways have been characterized, the full complement of genetic determinants that enable V. cholerae to sense, adapt to, and survive CAMP stress remains incompletely understood. Bacterial responses to environmental stress often involve two-component signaling (TCS) systems, including the CarRS system, which is critical for CAMP resistance and is one of the few regulators known to negatively regulate biofilm formation in V. cholerae. However, the mechanisms underlying CarRS-mediated antimicrobial resistance and biofilm regulation remain poorly understood. To comprehensively define the genetic and regulatory mechanisms underlying the V. cholerae CAMP response, we combined whole-genome...

Music, Online Community, and Parasocial Relationships: Lizzo as a Case Study

Fri, 11 Sep 2026 00:00:00 +0000

The purpose of this dissertation is to consider an alternative methodological framework for studying popular music and musicians particularly within historically marginalized groups. I explore the parasocial relationships between online fan audiences and musicians with Lizzo the artist as a case study. I chose Lizzo as a case study because of her platform online, where she communicates with fans to shape her musical culture and the art she produces. Moreover, Lizzo was faced with online “cancel-culture” due to sexual assault allegations that are complicated through her background as a marginalized woman of color. Through the social media platforms Instagram, Twitter, Reddit, and TikTok, this dissertation examines how online communities are mediated through an appreciation of Lizzo’s music. I also consider the implication of technology and a lack of shared geographical location, to question the imagined community’s authenticity for fans. I investigate negative responses to Lizzo...

Auslander-Reiten Theory for Equivariant Sheaves on Trees

Fri, 11 Sep 2026 00:00:00 +0000

In this thesis, we investigate the category of equivariant sheaves on a locally finite tree. We view this setting as an interesting junction between the representation theory of p-adic groups, and the geometric methods coming from quiver theory. Inspired by methods from quiver theory, we show that the category of (smooth) equivariant sheaves on a tree X is equivalent to a certain hereditary module category HX-mod. We construct HX explicitly as the endomorphism ring of a projective generator, which emulates the construction of path algebras for quivers, and Hecke algebras for p-adic groups. In this light, we investigate the implications of Auslander-Reiten theory in this context. In particular we provide a thorough investigation of a large class of sheaves known as the pre-injective component, and give recursive formulae for their cohomology.

Crop Response Under Water Deficit is Shaped by Adjustments in Plant Structure, Function, and Fruit Yield and Quality

Fri, 11 Sep 2026 00:00:00 +0000

As climate conditions become warmer and drier, there is an increased threat to agricultural productivity. Increased temperatures and reduced water availability can impede crop performance and reduce yields. However, the relative effects of drought on different crops and the consequences for yield is less well understood, specifically, the physiological and structural principles that underpin crop performance under water deficit. Understanding the limits of economically important crops, especially as growers transition towards more sustainable forms of agriculture, is critical. In order for these transitions to occur, it is useful to identify the crop varieties and the suite of traits that will allow them to thrive under limited resources. To identify these suite of traits that allow crops to survive under water deficit, I studied a combination of physiological, anatomical, and morphological traits in strawberries, tomatoes, and beans, grown under well-watered and water-deficit...

Loanwords in syntax: The projection of internal arguments

Fri, 11 Sep 2026 00:00:00 +0000

This dissertation argues that DP arguments cannot and should not be subsumed under a c(ategory)-selectional analysis, and are not licensed by the mechanisms that guide head-complement relations. I present three in-depth investigations of Sino-Korean loanwords and the construction of Sino- and native Korean complex predicates, making the following claims about the nature of internal argument realization: 1.) Internal arguments, unlike external arguments, cannot be severed from the lexical predicate, and are not introduced by a functional projection, of either the verbal or nominal domain (Chapter 2). In fact, Sino-Korean loanwords empirically necessitate that a categorical syntactic entities— Roots— are themselves internal argument introducers.2.) DP arguments are not always syntactically projected, though they are always semantically represented (Chapter 3). Syntactic argument projection, rather than being obligatory, is in fact one of two possible routes for the syntactic realization...

Data Centers Lower Nearby Housing Values

Thu, 10 Sep 2026 00:00:00 +0000

Artificial intelligence is driving unprecedented investment in data centers, yet the local costs and benefits of these facilities remain largely unmeasured. We estimate how households value nearby data center development using a newly constructed database of U.S. data centers and housing transaction data. Our statistical analysis uses a matched stacked event study design that compares housing transactions near newly announced large data centers with transactions in observably similar areas near data centers that are announced later. Large data centers reduce housing values within 3 miles by 3% on average over the following 5 years. The effect is highly localized: prices within 1 mile fall by 7.2% on average, with smaller effects beyond 1 mile. Price declines persist for at least 5 years and are larger for hyperscale and high-capacity data centers, urban locations, and the first large data center in an area. Consistent with increasing public awareness of data center externalities,...

Pelagic food web realignment supports resilient larvae of Southern Bluefin Tuna in a warming ocean

Thu, 10 Sep 2026 00:00:00 +0000

Many of the oceans' top predatory fishes at low to mid latitudes face an uncertain future as their vulnerable larvae deal with higher environmental temperature and reduced productivity associated with climate change. However, ocean ecosystem models that predict a general decline of zooplankton prey with warming and stratification hardly ever account for complexities in pelagic food webs that might make them resilient in providing food resources for larvae. We illustrate such complexities in comparing feeding interactions of larval Southern Bluefin Tuna (SBT) between two studies conducted 35 y apart in the same spawning region off northwest Australia. In the first (1987), SBT larvae fed and grew at low rates demonstrably limited by zooplankton prey. In the second (2022), feeding and growth were significantly higher despite substantially warmer conditions. The difference reflects a realignment in larval feeding preference from copepods to appendicularians, which allows a more direct...

A structural bridge between dengue virus tandem xrRNAs facilitates coordination of exonuclease resistance.

Wed, 2 Sep 2026 00:00:00 +0000

Orthoflavivirus RNA genomes resist host 5'-3' exoribonucleases to produce subgenomic flaviviral RNAs (sfRNAs). This resistance is conferred by exoribonuclease-resistant RNA (xrRNA) structures within the viral 3' untranslated region that often occur in tandem, and whose function can be coupled. In dengue virus serotype 2 (DENV2), this coupling results in changing patterns of sfRNA identity and abundance associated with the ability of the virus to adapt to host vs. vector infections. The physical basis of this coupling was unknown. Using a combination of virology, biochemistry, bioinformatics, structural biology, and biophysics, we explored the structural and sequence determinants of tandem xrRNA coupling in DENV2. We discovered that the spatial proximity, order, and structural integrity of the tandem xrRNAs are all important for coupling. Furthermore, an unpaired A-rich linker that lies between the two xrRNAs is essential in stabilizing a specific structure that correlates to coupling....

SIM 2.0: Floor Plan Vectorization via VLM Semantic Normalization with Pixel-Wise Self-Consistency

Wed, 2 Sep 2026 00:00:00 +0000

SIM 2.0: Floor Plan Vectorization via VLM Semantic Normalization with Pixel-Wise Self-Consistency

Combined effective field theory interpretation of Higgs boson, electroweak vector boson, top quark, and multijet measurements

Mon, 31 Aug 2026 00:00:00 +0000

Constraints on Wilson coefficients (WCs) corresponding to dimension-6 operators of the standard model effective field theory (SMEFT) are determined from a simultaneous fit to seven sets of CMS measurements probing Higgs boson, electroweak vector boson, top quark, and multijet production. Measurements of electroweak precision observables are also included and provide complementary constraints to those from the CMS experiment. The CMS measurements, using LHC proton-proton collision data at s=13Te$$\sqrt{s}=13\,\text {Te}\text {V} $$, corresponding to integrated luminosities of 36.3 or 138fb-1$$\,\text {fb}^{-1}$$, are chosen to provide sensitivity to a broad set of operators, for which consistent SMEFT predictions can be derived. These are primarily measurements of differential cross sections which are parameterized as functions of the WCs. In measurements targeting t(t¯)X$${\text {t}} (\bar{\textrm{t}})\text {X} $$ production, SMEFT effects are modelled at the detector level. Individual...

A review and analysis of Fourier transform spectroscopy in the soft x-ray region: advancing historical designs with modern technology

Sat, 29 Aug 2026 00:00:00 +0000

We present a comprehensive review of Fourier transform spectroscopy in the soft x-ray region, focusing on Mach-Zehnder interferometer configurations. This study evaluates advantages over traditional grating-based methods, including higher resolution potential (>10,000) and rapid data acquisition. We examine historical implementations and their limitations, highlighting how recent advances in laser interferometry, mechanical stability, and detector technology may enable successful development. Through detailed simulations of interferometer schemes and beam splitter designs, we demonstrate how modern piezoelectric stages and feedback systems could overcome previous technical challenges. Applications for resonant inelastic x-ray scattering (RIXS) experiments at advanced light sources are discussed.

Use of Citizen Science, Social Media, and AI to Track White Whales in the Kingdom of Tonga and Australian Waters

Fri, 28 Aug 2026 00:00:00 +0000

Use of Citizen Science, Social Media, and AI to Track White Whales in the Kingdom of Tonga and Australian Waters

Structural and fluid evolution of a young accretionary complex: The Hoh rock assemblage of the western Olympic Peninsula, Washington

Thu, 27 Aug 2026 00:00:00 +0000

The Hoh rock assemblage of the western Olympic Peninsula, Washington, was Deposited in Eocene to Miocene time, and accreted, deformed, uplifted, and eroded by the late Miocene. Northeast-dipping fault zones within the Hoh are characterized by intensely deformed mud matrix mélange, and they range from ∼200 m to >1,000 m thick; kinematic indicators within the matrix indicate thrusting to the west-southwest. Both hanging-wall and footwall sections are strongly folded and faulted. Wall-rock sections are lithostratigraphically distinct, with hanging walls composed of massive coarse sandstone and conglomerate, and footwall sections composed of thin- to medium- bedded sandstone and siltstone. Folds within the wall-rock sections are oblique to, and are truncated by, the later fault-zone mélanges, indicating that the fault zones postdate folding. Evidence of fluid involvement in the Hoh rocks includes petroliferous outcrops, carbonate and clay cement, and veins of carbonate and laumontite....

High density of structurally controlled, shallow to deep water fluid seep indicators imaged offshore Costa Rica

Thu, 27 Aug 2026 00:00:00 +0000

We used high‐resolution mapping to document 161 sites of potential fluid seepage on the shelf and slope regions where no geophysical seep indicators had been reported. Identified potential seabed seepage sites show both high‐backscatter anomalies and bathymetric expressions, such as pockmarks, mounds, and ridges. Almost all identified seabed features are associated with bright spots and flat spots beneath, as mapped within the 3‐D seismic grid. We obtained EM122 multi‐beam data using closely spaced receiver beams and 4–5 times overlapping multi‐beam swaths, which greatly improved the sounding density and geologic resolvability of the data. At least one location shows an acoustic plume in the water column on a 3.5 kHz profile, and this plume is located along a fault trace and above surface and subsurface seepage indicators. Fluid indicators are largely associated with folds and faults within the sediment section, and many of the faults continue into and offset the reflective basement....

Learning With Diagrams and Visualizations: Visual, Learner, and Contextual Factors

Thu, 27 Aug 2026 00:00:00 +0000

Diagrams and visualizations can be seen throughout educational materials, such that their presence is almost ubiquitous. The assumption is that including visualizations in lessons will lead to greater learning. In this paper, I review the psychological and educational literature to examine how the presence of visualizations influences learning in STEM fields. In particular, I examine how the effectiveness of a visualization depends on characteristics of the visualization, the learner, and the context. Characteristics of the visualization are important insofar as they highlight relevant information and reduce extraneous details. Learner characteristics influence how people learn with visualizations, but more work is needed to isolate these relations. The characteristics of the context are a critical but underexplored area in multimedia learning. This review highlights that visualizations are not universally helpful for learning, but rather their effect depends on a myriad of factors...

Structural aspects of diapiric mélange emplacement: the Duck Creek diapir

Thu, 27 Aug 2026 00:00:00 +0000

The Duck Creek mélange is one of a series of diapiric mud intrusions into the slope cover sequence of the Cascadia Accretionary Wedge. The diapir originated deep within the accreted Hoh sequences and has intruded approximately 1 km up into the 2–3 km thick Pliocene Quinault slope cover sequences at its current level of exposure in coastal seacliffs. Analyses of the geometry and kinematic indicators at the current exposure level strongly suggest that this part of the diapir intruded at a low angle to form an inclined sill or dyke-like body at least 0.5 km in diameter. Microstructural analysis indicates a zonation of deformational features between the core and margins of the diapir resulting from an evolving series of fabrics and the increasing concentration of strain towards the margins. Specifically, we interpret early independent particulate flow (IPF) fabrics as indicating deformation in a low effective stress environment with the possibility of turbulence during initial mobilization...

Early Pleistocene ecosystem turnover in South Siberia linked to abrupt regional cooling

Thu, 27 Aug 2026 00:00:00 +0000

Earth system feedbacks can amplify greenhouse gas forcing but are difficult to quantify, particularly on land where long palaeoclimate records are scarce. Here we reconstructed warm-season temperatures and vegetation at Lake Baikal, Russia, over the past 8.6 million years. We document gradual late Neogene cooling that was punctuated by an abrupt transition approximately 2.7 million years ago to severe cold temperatures during glacial periods. Forests were replaced by open steppe–tundra ecosystems and permafrost probably extended into South Siberia during these Early Pleistocene cold intervals. Compiled palaeobotanical data suggest this ecosystem turnover occurred throughout the Arctic and subarctic, although the timescale of these changes is less understood. Reconstructed Early Pleistocene glacial temperatures and vegetation resemble Late Pleistocene glacial periods at Lake Baikal, despite much warmer mean global temperatures in the Early Pleistocene. These geologic observations...

Sea bottom characteristics and geochemistry of oil and gas seeps in the Gulf of Mexico

Thu, 27 Aug 2026 00:00:00 +0000

Abstract From 2015 to 2018, TGS conducted a comprehensive multiclient oil and gas seep mapping survey in the Gulf of Mexico (GOM). The basis for identifying seeps on the sea bottom was a high-resolution multibeam echosounder survey, mapping approximately 880,000 km2 of the sea bottom deeper than 750 m water depth, at a bathymetric resolution of 15 m, and a backscatter resolution of 5 m. We identified more than 5000 potential oil and/or gas seeps, and of those, we cored approximately 1500 for hydrocarbon geochemical analysis. The sea bottom features best related to hydrocarbon seepage in the GOM are high backscatter features, mud volcanoes, pock marks, brine pools, “popcorn” texture, fault traces, and anticlinal crests. We also tracked gas plumes in the water column back to the sea bottom to provide an additional criterion for hydrocarbon seepage. Cores from sea bottom targets recovered liquid oil, tar, and gas hydrates. Oil extract and gas analyses of samples...

Geophysical evidence for gas geohazards off Iskenderun Bay, SE Turkey

Thu, 27 Aug 2026 00:00:00 +0000

High-resolution seafloor and sub-surface data were acquired as part of a site survey in Iskenderun Bay, SE Turkey to characterize the geohazards at the location of the proposed drilling site. A 3km×3km geophysical study reveals a pockmark field which trends NE and NNE, similar to the trend of major fault systems in the area. The pockmarks, with an average diameter of 35m, reach their highest density in the northern part of the detailed survey area, with 13features/km2. Acoustic anomalies in the seismic records (acoustic turbidity, blanking, enhanced reflectors) below the proposed drilling site indicated potential shallow gas beneath it. The local seismic anomalies (amplitude and frequency) parallel to stratigraphy were assigned a low gas risk. As a result of the active neotectonics in the area, the pockmark field presented a potential hazard for drilling at the original location. The geohazard study resulted in moving the proposed drilling site eastward to an area of fewer pockmarks,...

From Permits to Samples: Addressing Key Challenges for High-Quality Reference Genome Generation in Europe.

Thu, 27 Aug 2026 00:00:00 +0000

High-quality reference genome assemblies have become essential for deepening our understanding of biodiversity, yet obtaining them for many species remains surprisingly challenging. Drawing on experiences from the European Reference Genome Atlas (ERGA) community, we focus on permit and sample-handling procedures leading up to nucleic acid sequencing, covering tasks such as ensuring ethical and legal compliance, verifying accurate species identification, maintaining sample integrity during transport, and isolating high-quality DNA or nuclei. While many of the challenges and solutions we discuss are broadly relevant, our regulatory and logistical examples are primarily from Europe. By synthesising practical guidance, we highlight the crucial importance of taxonomic expertise, proper vouchering and biobanking, rigorous cold-chain management or alternative preservation methods, and emphasise adherence to packaging and shipping requirements for biological materials. We showcase examples...

Evidence for superelevation, channel incision, and formation of cyclic steps by turbidity currents in Eel Canyon, California

Thu, 27 Aug 2026 00:00:00 +0000

We performed a multibeam survey of Eel Canyon, offshore northern California. The survey revealed a significant bend in the canyon that appears to be due to the oblique compressional tectonics of the region. A series of steps within a linear depression, ∼280 m above the canyon floor, extends from the canyon rim at this bend to the subduction zone and a distinct fan-like topographic rise. We hypothesize that the linear depression is a distributary channel and the steps are cyclic-step bedforms created by turbidity currents. Our interpretation indicates that turbidity currents are able to run up and overspill the 280-m-high canyon wall, resulting in a partial avulsion of the canyon and the construction of a fan lobe that is offset from the canyon mouth. Simple hydraulic calculations show that turbidity currents generated in the canyon head from failure of 2–3 m of material would be capable of partially overflowing the canyon at this bend, assuming steady-uniform flow, full conversion...

Use of multibeam bathymetry and backscatter to improve seabed geochemical surveys — Part 1: Historical review, technical description, and best practices

Thu, 27 Aug 2026 00:00:00 +0000

Abstract Oil and gas seeps have been a key tool in hydrocarbon exploration since ancient times. Basin-wide reconnaissance exploration, focused on basic geology and identification of hydrocarbon seepage, has been typical of onshore basin analysis since the beginning of the petroleum industry. Since the discovery of marine chemosynthetic “cold seep” communities in the mid-1980s, and their association with offshore oil and gas seepage, the energy industry has been mapping seeps to target them for exploration and avoid them in development. For exploration, the successful sampling of oil or gas at the seafloor reduces exploration risk by demonstrating generative source rock, maturation, migration, and charge — all key data about the subsurface petroleum systems. In the marine environment, seep communities and associated diagenetic precipitates can modify the bathymetry and/or the backscatter and can be imaged by multibeam echo sounder (MBES). MBES can provide detailed bathymetry of...

Fluid flow along a strike-slip fault at the toe of the Oregon accretionary prism: Implications for the geometry of frontal accretion

Thu, 27 Aug 2026 00:00:00 +0000

Sediment offscraping and accretion takes place predominantly by landward-vergent thrusting along most of the Oregon accretionary prism north of latitude 44°50'N. This indicates very low basal shear stress, probably due to near-lithostatic fluid pressure on the décollement horizon. Recent multichannel seismic and sidescan sonar studies have demonstrated the existence of an oblique, basement-involved, left-lateral strike-slip fault, termed the Wecoma fault. It cuts abyssal plain sediments and oceanic basement of the subducting plate. Where the Wecoma fault intersects the wedge thrust front at 45°09'N, accretion to the wedge occurs through an anomalous seaward-vergent thrust. Linear, fault-parallel erosional gullies, which trend obliquely across the slope on the seaward flank of the frontal anticline in the accretionary wedge, are interpreted as marking the surface traces of splays of the Wecoma fault. Data collected during six Alvin dives on and around these gullies demonstrate...

Geolipidomics: Non‐Targeted Analysis of Rapidly Heated Geologic Samples With Gas‐Chromatography‐Mass Spectrometry

Thu, 27 Aug 2026 00:00:00 +0000

Abstract Lipids are powerful tools for reconstructing paleoenvironments and geologic processes because of their ubiquity and preservation in the rock record. Traditionally, organic geochemistry studies are targeted analyses of known biomarker compounds with known responses to past environmental conditions or geologic processes. With the recent development of the lipidomics field in the biological sciences, there is an opportunity for non‐targeted analysis to identify new biomarkers. However, lipids in the rock record integrate processes from biologic to geologic (i.e., diagenesis, heating, catagenesis) resulting in more chemically complex matrices than biological samples. As non‐targeted “‐omics” approaches are transferred from biology and applied to sediment, soil, and rock samples to perform geolipidomics, they must be evaluated and potentially adapted for geologic samples. Here we compare four non‐targeted methods of extracting features consisting of a peak area and spectrum...

A comparison of relative stopping power derived by fast kV‐switching dual‐energy CT, single‐energy CT, and proton CT in phantom and tissue

Thu, 27 Aug 2026 00:00:00 +0000

BACKGROUND: The accuracy of relative stopping power (RSP) is a critical aspect for safe treatment planning in proton therapy. Dual-energy CT (DECT) has the ability to estimate RSP more accurately than conventional single-energy CT (SECT) due to its improved material separation. RSP accuracy is commonly determined in homogeneous phantom material as it can be more challenging to determine in heterogeneous biological tissues. Proton CT (pCT) is a modality that directly determines RSP and can be used as a comparative benchmark for evaluating the RSP accuracy of DECT and SECT derived values across homogeneous and heterogeneous material. PURPOSE: In this study, DECT was compared to SECT in both homogeneous phantom inserts of known RSP and heterogeneous tissue samples of unknown RSP using pCT as a quantitative reference. The purpose of this study was to assess the ability of DECT to improve RSP estimation over SECT in unknown RSP of heterogeneous tissues. METHODS: A variety of homogeneous...

Thermal Reactions of Smectite Minerals at Earthquake Timescales

Thu, 27 Aug 2026 00:00:00 +0000

Abstract Frictional heating causes a transient temperature rise in fault zones during earthquakes that leads to metamorphic reactions within the fault rocks. The products of these reactions provide potential evidence of earthquakes in both the outcrop and drill core. Clay minerals such as smectites are commonly found in faults. When heated, they experience a sequence of reactions with increasing temperature: dehydration, dehydroxylation, and decomposition. Clay reactions have been suggested as rock record evidence of past earthquakes, but whether these reactions are fast enough to occur over earthquake timescales (seconds‐minutes) depends on unknown reaction kinetics. We conducted ramped and isothermal heating experiments up to 900°C on smectite clays using in situ X‐ray diffraction (XRD) to monitor reactions as they progressed. Dehydration was variable across experiments due to sensitivity to ambient humidity and therefore accurate kinetics could not be determined for this reaction....

Slope basins, headless canyons, and submarine palaeoseismology of the Cascadia accretionary complex

Thu, 27 Aug 2026 00:00:00 +0000

A combination of geomorphological, seismic reflection and geotechnical data constrains this study of sediment erosion and deposition at the toe of the Cascadia accretionary prism. We conducted a series of ALVIN dives in a region south of Astoria Canyon to examine the interrelationship of fluid flow and slope failure in a series of headless submarine canyons. Elevated head gradients at the inflection point of canyons have been inferred to assist in localized failures that feed sediment into a closed slope basin. Measured head gradients are an order of magnitude too low to cause seepage‐induced slope failure alone; we therefore propose transient slope failure mechanisms. Intercanyon slopes are uniformly unscarred and smooth, although consolidation tests indicate that up to several metres of material may have been removed. A sheet‐like failure would remove sediment uniformly, preserving the observed smooth intercanyon slope. Earthquake‐induced liquefaction is a likely trigger for...

CRITICAL VALUES ROBUST TO P-HACKING

Thu, 27 Aug 2026 00:00:00 +0000

CRITICAL VALUES ROBUST TO P-HACKING

High-resolution Surveys for Geohazards and Shallow Gas: NW Adriatic (Italy) and Iskenderun Bay (Turkey)

Thu, 27 Aug 2026 00:00:00 +0000

The need for quantifying and understanding the distribution of shallow gas is both of academic interest and of relevance to offshore facilities. The combination of seafloor mapping, subbottom profiling, and multi-channel seismic data can provide information on regions of possible shallow gas, where the gas impacts the acoustic properties of the host material and the seafloor. In this paper, we present two case studies – one academic and one industry – that evaluate the distribution of shallow gas in two field areas in the Mediterranean. In the first case study, geophysical data from Iskenderun Bay, southeastern Turkey, indicate the presence and distribution of shallow gas. Pockmarks on the seafloor are associated with acoustic wipeout in the shallow subbottom data. Although deeper seismic data do not show bright spots or other indicators of possible gas, instantaneous frequency analysis clearly shows laterally restricted anomalies indicating gas-rich zones. The interpretation...

Children's understanding of COVID-19 and the flu in three demographically distinct U.S. communities.

Thu, 27 Aug 2026 00:00:00 +0000

Children's understanding of illness reflects their developing views of the biological world and predicts the protective measures they engage in. However, most of the research to date has focused on children from the communities surrounding research universities and as such might not provide a generalizable view of how children across the United States think about illnesses and viruses. This is of particular concern with regard to the COVID-19 pandemic, as Black and Latinx communities experienced more hospitalizations and deaths, and rural conservative communities were the targets of misinformation. We examined beliefs about two illnesses (COVID-19 and the flu) in 5- to 12-year-old children (N = 313) and their parents (N = 194), from three different types of communities across the United States: university communities (N_children = 104; N_parents = 64), low-socioeconomic-status Black and Latinx communities (N_children...

Distinct genomic architectures but the same gene underlie the convergent evolution of a plant supergene.

Thu, 27 Aug 2026 00:00:00 +0000

Evolution reflects a balance between innovation and constraint, often repurposing existing components in new contexts. Convergent evolution exemplifies this interplay, with similar traits evolving independently in different species, yet the genomic mechanisms enabling this repeatability remain poorly understood. Here, by analyzing 10 chromosome-scale genome assemblies, including seven newly generated, we found that the S-locus supergene (a cluster of tightly linked genes controlling a floral dimorphism called distyly) arose independently multiple times within the primrose family, Darwin's iconic system for studying distyly. In each case, the same gene was independently duplicated and co-opted. However, the resulting genomic architectures differed, ranging from hemizygous (present on one chromosome copy) to heterozygous (on both copies), challenging the prevailing view that hemizygosity is intrinsic to S-loci and suggesting alternative evolutionary routes to distyly...

Twentieth century extreme precipitation detected in a high-resolution, coastal lake-sediment record from California

Thu, 27 Aug 2026 00:00:00 +0000

California faces increasing economic and societal risks from extreme precipitation and flooding associated with atmospheric rivers (ARs) under projected twenty-first century climate warming. Lake sediments can retain signals of past extreme precipitation events, allowing reconstructions beyond the period of instrumental records. Here, we calibrate AR-related extreme precipitation from the last century to proxy data from lake sediments collected in the latitudinal zone of the highest frequency landfall for modern ARs in California. Excursions in erosional proxy data (Ti/Al) are positively and significantly correlated (rmedian = 0.45, pmedian = 0.04) with modern records of integrated vapor transport (IVT, kg m−1 s−1), a key metric of AR intensity, using correlations that incorporate age-model uncertainty. Despite the land-use change near the study site, the data suggest intense and long-lasting AR storms are identifiable in this sedimentary record. These results allow...

An exploration of assembly strategies and quality metrics on the accuracy of the rewarewa (Knightia excelsa) genome.

Thu, 27 Aug 2026 00:00:00 +0000

We used long read sequencing data generated from Knightia excelsa, a nectar-producing Proteaceae tree endemic to Aotearoa (New Zealand), to explore how sequencing data type, volume and workflows can impact final assembly accuracy and chromosome reconstruction. Establishing a high-quality genome for this species has specific cultural importance to Māori and commercial importance to honey producers in Aotearoa. Assemblies were produced by five long read assemblers using data subsampled based on read lengths, two polishing strategies and two Hi-C mapping methods. Our results from subsampling the data by read length showed that each assembler tested performed differently depending on the coverage and the read length of the data. Subsampling highlighted that input data with longer read lengths but perhaps lower coverage constructed more contiguous, kmers and gene-complete assemblies than short read length input data with higher coverage. The final genome assembly was constructed into...

A diatom-based quantitative sea-ice proxy for the Bering and Chukchi seas

Thu, 27 Aug 2026 00:00:00 +0000

Sea ice affects Earth's climate system on both regional and global scales. Its incorporation into climate can be used to achieve more accurate predictions of future climate. However, instrumental records of sea-ice concentration do not extend earlier than 1978. In an effort to extend this record, we constructed a proxy using the generalized additive model based on relative abundances of five easy-to-identify diatom species found in sediment samples across the Bering and Chukchi seas. Here we present the first quantitative diatom-based sea-ice proxy developed for Beringia. The developed proxy has been applied to two sediment cores in the Bering Sea ranging from 0 to 25.7 ka (HLY0204 51JPC) and 369 to 430 ka (IODP Exp 323 Site U1345) and one in the Chukchi Sea ranging from 2.7 to 10 ka (HLY0204 24JPC). The obtained reconstructions of sea-ice concentrations are similar, but not identical to previously published qualitative and nearby records based on other proxies....

Contextualising samples: supporting reference genomes of European biodiversity through sample and associated metadata collection.

Thu, 27 Aug 2026 00:00:00 +0000

The European Reference Genome Atlas (ERGA) consortium aims to generate a reference genome catalogue for all of Europe's eukaryotic biodiversity. The biological material underlying this mission, the specimens and their derived samples, are provided through ERGA's pan-European network. To demonstrate the community's capability and capacity to realise ERGA's ambitious mission, the ERGA Pilot project was initiated. In support of the ERGA Pilot effort to generate reference genomes for European biodiversity, the ERGA Sampling and Sample Processing committee (SSP) was formed by volunteer experts from ERGA's member base. SSP aims to aid participating researchers through (i) establishing standards for and collecting of sample/specimen metadata; (ii) prioritisation of species for genome sequencing; and (iii) development of taxon-specific collection guidelines including logistics support. SSP serves as the entry point for sample providers to the ERGA genomic resource production infrastructure...

Astrovirus and norovirus infections and their association with diarrheal symptoms in immunocompromised children

Thu, 27 Aug 2026 00:00:00 +0000

Human astroviruses are a common cause of viral gastroenteritis and are often underdiagnosed. While infections are typically mild or asymptomatic in immunocompetent hosts, astrovirus can cause prolonged and severe disease in immunocompromised individuals. Here, we conducted a case-control study to evaluate the clinical presentation of astrovirus infections in paediatric oncology patients. Our findings were compared to two groups: (1) norovirus infections in the same immunocompromised cohort, and (2) a cohort of immunocompetent children with and without diarrheal symptoms. Astrovirus was detected in 9.8% of immunocompromised patients, with prolonged shedding seen in multiple cases. Astrovirus infection was associated with an increased odds of diarrhoea, although this association weakened when adjusting for co-infections. In contrast, norovirus was not significantly associated with diarrhoea in immunocompromised patients, despite prolonged shedding in 24% of the cohort. High rates...

Financial value of nature: coastal housing markets, mangroves, and climate resilience

Thu, 27 Aug 2026 00:00:00 +0000

Measuring the financial value of nature is difficult, often resulting in insufficient funding directed to nature conservation and restoration. As coastal risks increase due to development and climate change, a tangible benefit of nature is the protection it offers against storm damage. Many studies from the risk industry and others assess the direct effects of wetlands for reducing damage during storms. However, the value of wetlands for coastal protection could extend to many other benefits, including home prices in areas where storms are common. We use property-level housing transaction data from Zillow and show that proximity to mangroves in Florida moderates home price decline and dispersion following major hurricanes. The effects are substantial in magnitude, reducing the probability of losing a quarter or more of the housing value by 2–7 percentage points, which corresponds to 20–40-thousand-dollar value for a million-dollar property, conditional on a hurricane.

A Riemann–Hilbert approach to asymptotic analysis of Toeplitz+Hankel determinants II

Thu, 27 Aug 2026 00:00:00 +0000

In this article, we further develop the Riemann–Hilbert formalism introduced in our earlier work [Gharakhloo and Its, SIGMA 16 (2020), 100] for the asymptotic analysis of Toeplitz+Hankel determinants with distinct Toeplitz and Hankel symbols. In that work, we showed that the associated Riemann–Hilbert problem can be analyzed by the Deift–Zhou nonlinear steepest descent method under a special restriction on the winding numbers of the symbols. This restriction excludes several natural cases, including the zero–winding configuration for both ϕ and w. The main goal of the present paper is to extend the asymptotic analysis of Toeplitz+Hankel determinants to a broader class of winding–number configurations. As an application, we study the case associated with the Ising model on the zig–zag layered half–plane with critical boundary magnetic field, for which the winding numbers of the Toeplitz and Hankel symbols are 0 and −1, respectively. In this setting, we compute the asymptotics of...

Chapter Seven Understanding Strategy Change: Contextual, Individual, and Metacognitive Factors

Thu, 27 Aug 2026 00:00:00 +0000

Learning, development, and response to instruction often involve changes in the strategies that learners use to solve problems. In this chapter, our focus is on mathematical problem solving in both children and adults. We offer a selective review of research on three classes of factors that may influence processes of strategy change in mathematical problem solving: contextual factors, individual factors, and metacognitive factors. Contextual factors involve information that learners encounter in the learning context, such as feedback about prior strategies and examples of alternative strategies. Individual factors involve the abilities, dispositions, and knowledge that learners bring to the learning context. Metacognitive factors involve knowledge about strategies and factors that affect the application of strategies-including perceptions of problem difficulty, confidence in the strategies one already knows, and judgments about the qualities of alternative strategies. These factors...

A multiproxy reconstruction of changes in sea ice and primary productivity at IODP Site U1339 (Umnak Plateau, Bering Sea) during Marine Isotope Stage 11

Thu, 27 Aug 2026 00:00:00 +0000

Abstract The extreme warmth of Marine Isotope Stage (MIS) 11 has been extensively studied in the terrestrial realm; however, less is known about its expression in the North Pacific. Here, we present a multiproxy record from Integrated Ocean Drilling Program (IODP) Site U1339 in the southeastern Bering Sea (Umnak Plateau). We use sedimentology, diatoms, and organic geochemistry to reconstruct sea ice and primary productivity from the end of MIS 12 to the beginning of MIS 10 (430–368 ka) at this site. In late MIS 12, the Umnak Plateau experienced extensive seasonal sea ice cover, with spring sea ice concentration near 100%. Based on diatoms and ice-rafted debris, sea ice declined to year-round ice-free conditions during deglaciation but readvanced during the interglacial climatic optimum. In contrast, sea ice has not been present at the Umnak Plateau throughout the Holocene. During MIS 11, sea ice at this site may have persisted due to a more easterly and/or weaker Aleutian Low....

Use of multibeam bathymetry and backscatter to improve seabed geochemical surveys — Part 2: Best practices and case studies in seep hunting for exploration, with an emphasis on Indonesia

Thu, 27 Aug 2026 00:00:00 +0000

Abstract The successful sampling of seafloor oil and gas seeps can provide information on source rock, migration, maturation, and charge that can impact exploration decisions. Although 3D seismic data can be interpreted for potential seafloor seeps, multibeam can be acquired over larger areas at lower cost and in a shorter turnaround time, with bathymetry, backscatter, and water column imagery leading to the interpretation of potential seafloor seep targets. The use of multibeam-based exploration early in an exploration project can provide information on the petroleum systems in an area and also areas where no evidence of a petroleum system is present on the seafloor. We have developed case studies of block-specific seep hunting and regional multibeam surveys. For regional surveys, multibeam can be combined with 2D seismic data, ultrashort baseline (USBL)-positioned piston coring, heat flow, high-resolution subbottom profiles, marine gravity and magnetics, and core geochemistry...

The origin and development of the Miocene northwest African savanna

Thu, 27 Aug 2026 00:00:00 +0000

Like many of Earth's subtropical open ecosystems, the African savanna originated in the Miocene Epoch (23.0 to 5.3 Ma), one of the best historical analogs for future climate states. The first C₄ grass, C₃ tree, and shrub savanna developed in the subtropics after ~10 Ma in northwest Africa, but the terrestrial sedimentary record of the region is not well preserved, making it difficult to determine when, how, and why the African landscape opened. Here, we leverage plant-wax biomarkers extracted from the marine sedimentary archive to document the origination and history of open ecosystems through Miocene northwest Africa. We show that a C₃ grass-rich savanna with no modern analog replaced closed woodlands and forests during the middle Miocene (~15 to 14 Ma), a period of global cooling and aridification. This nonanalog ecosystem transitioned into the C₄ savanna in stages in the late Miocene (most rapidly between 7.4 to 6.4 Ma) as global...

Building a Portuguese coalition for biodiversity genomics

Thu, 27 Aug 2026 00:00:00 +0000

The diverse physiography of the Portuguese land and marine territory, spanning from continental Europe to the Atlantic archipelagos, has made it an important repository of biodiversity throughout the Pleistocene glacial cycles, leading to a remarkable diversity of species and ecosystems. This rich biodiversity is under threat from anthropogenic drivers, such as climate change, invasive species, land use changes, overexploitation, or pathogen (re)emergence. The inventory, characterisation, and study of biodiversity at inter- and intra-specific levels using genomics is crucial to promote its preservation and recovery by informing biodiversity conservation policies, management measures, and research. The participation of researchers from Portuguese institutions in the European Reference Genome Atlas (ERGA) initiative and its pilot effort to generate reference genomes for European biodiversity has reinforced the establishment of Biogenome Portugal. This nascent institutional network...

Transgressive deposits along the actively deforming Eel River Margin, Northern California

Thu, 27 Aug 2026 00:00:00 +0000

New high-resolution CHIRP seismic data acquired along the Eel River margin, northern California, reveal that stratal architecture and sediment thickness of the Holocene transgressive deposits are, in large part, controlled by tectonic deformation and sediment supply. A thick (>20m) transgressive deposit is observed across the Eel margin, a forearc basin that is undergoing active folding perpendicular to the coastline at rates of mm/yr. The transgressive deposits on the Eel margin exhibit marked variations in thickness alongshore; being thickest in the Eel River Syncline and thinnest over the Eureka Anticline. The divergent character of the infill in the syncline suggests that deposition is syntectonic. Fault displacement and structural relief observed along the transgressive surface are consistent with deformation rates measured onshore. The transgressive surface is offset ~0.5m across the Eureka Anticline suggesting deformation has been active since ~10ka. Two distinct acoustic...

Author Correction: The European Reference Genome Atlas: piloting a decentralised approach to equitable biodiversity genomics

Thu, 27 Aug 2026 00:00:00 +0000

Author Correction: The European Reference Genome Atlas: piloting a decentralised approach to equitable biodiversity genomics

Electrochemical energy for living systems

Sun, 23 Aug 2026 00:00:00 +0000

Plastoquinone and ubiquinone play essential roles in the electron transport chains of chloroplasts and mitochondria by coupling electron transport to the transfer of protons across membranes. The energy of the resulting proton gradient is used to synthesize adenosine triphosphate (ATP), the energy currency of all life. How did quinones first become involved in this process? We have detected several quinone compounds in carbonaceous meteorites that can transport protons in a liposome model system. It is possible that such compounds were available to transport protons in primitive versions of electron transport in early life.

Measurement of the Higgs boson production in association with top quarks in multilepton final states in pp collisions at s=13 TeV with the ATLAS detector

Thu, 20 Aug 2026 00:00:00 +0000

A measurement of the associated production of a top-quark pair with the Higgs boson (tt¯H$$ t\overline{t}H $$) in multilepton final states is presented. The analysis is based on a data sample of proton-proton collisions at s=13$$ \sqrt{s}=13 $$ TeV recorded with the ATLAS detector at the CERN Large Hadron Collider and corresponding to an integrated luminosity of 140 fb−1. Six final states defined by the number and flavour of reconstructed charged leptons are combined in a simultaneous likelihood fit to extract the tt¯H$$ t\overline{t}H $$ signal and constrain the most relevant backgrounds. The measured tt¯H$$ t\overline{t}H $$ cross-section normalised to Standard Model (SM) prediction is σtt¯H/σSM=0.63−0.19+0.20$$ {\sigma}_{t\overline{t}H}/{\sigma}^{\mathrm{SM}}=0.{63}_{-0.19}^{+0.20} $$. This result corresponds to an observed (expected) significance of 3.3σ (5.3σ). Additionally, two other fits are used to measure the tt¯H$$ t\overline{t}H $$ cross-section differentially in bins...

Search for higgsinos in compressed mass spectra using low-momentum tracks in pp collisions at s=13 TeV with the ATLAS detector

Wed, 19 Aug 2026 00:00:00 +0000

This paper presents two searches for the electroweak production of higgsinos with compressed mass spectra using 140 fb−1 of s=13$$ \sqrt{s}=13 $$ TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider. Events are required to feature an energetic jet, large missing transverse momentum, and at least one low-momentum charged particle that serves as a candidate higgsino decay product. In the first search, targeting higgsino mass splittings in the range of 0.3–1 GeV, the higgsinos are expected to predominantly decay into pions that are identified as low-momentum charged particles with large transverse impact parameters due to the long higgsino lifetime (cτ ≈ ?(0.1–10 mm)), and neural networks are used to discriminate between signal and background processes. The second search targets larger mass splittings in the range of 1–3 GeV, where the higgsinos are expected to decay promptly into low-momentum leptons, one of which is identified by dedicated...

Characterization of nuclear breakup as a function of hard-scattering kinematics using dijets measured by ATLAS in p+Pb collisions

Wed, 19 Aug 2026 00:00:00 +0000

This Letter analyzes the sensitivity of event geometry estimators to the initial-state kinematics of hard scattering in proton–lead collisions. This analysis uses dijets as a proxy for the parton–parton scattering configuration, correlating it with event geometry estimators, namely the energy deposited in the Zero-Degree Calorimeter and the transverse energy recorded in the Forward Calorimeter in the Pb-going direction. The analysis uses data recorded by the ATLAS detector at the Large Hadron Collider with a nucleon–nucleon center-of-mass energy of 8.16 TeV, corresponding to an integrated luminosity of 56 nb − 1 . The jets are measured within the pseudorapidity interval −2.8  <  η  <  4.5, where positive η values correspond to the direction of the proton beam. Results are presented as a function of the Bjorken-x of the parton originating from the proton, xp . Both event geometry estimators are found to be dependent on xp , with the energy deposited in the Zero-Degree Calorimeter...

Search for decays of the Higgs boson into pair-produced pseudoscalar particles decaying into τ+τ−τ+τ− using pp collisions at s=13 TeV with the ATLAS detector

Wed, 19 Aug 2026 00:00:00 +0000

A search for a pair of low-mass pseudoscalars a that promptly decay into τ-leptons is presented using 140 fb −1 of proton–proton collision data at 13 TeV centre-of-mass energy recorded with the ATLAS detector at the Large Hadron Collider. The result is used to place constraints on exotic decays of the Higgs boson into four τ-leptons, H→aa→τ+τ−τ+τ−. This search focuses on events with either one or two τ-leptons decaying into hadrons and neutrinos, and the remaining three or two τ-leptons decaying into either electron or muon and neutrinos. No significant excess is observed above the expected Standard Model background and upper limits at the 95% confidence level on B(H→aa→τ+τ−τ+τ−) are set ranging from 0.06 to 0.23, depending on the mass ma ranging from 15 to 60 GeV.

Search for dimuon resonance in the 35 to 75 GeV mass range using 140 fb−1 of 13 TeV pp collisions with the ATLAS detector

Tue, 18 Aug 2026 00:00:00 +0000

A model-independent search for low-mass resonances decaying into pairs of oppositely charged muons is presented. The analysis uses proton-proton collision data corresponding to an integrated luminosity of 140 fb−1, recorded by the ATLAS detector at the Large Hadron Collider between 2015 and 2018. The search targets hypothetical dimuon resonances in the invariant mass range from 35 GeV to 75 GeV. The modelling of this mass region is particularly challenging for conventional analytic background parameterisations. To address this, a Gaussian process regression technique is used to model the background. The dimuon mass spectrum is analysed for potential signals, and no statistically significant excess is observed. Upper limits at the 95% confidence level are set on the fiducial production cross-section of new resonances decaying promptly into muons, ranging from 20 fb to 110 fb, depending on the resonance mass. These results are further interpreted in the context of dark-photon and...

Mobile genetic elements shape microbial diversity and functions in thawing permafrost soils

Tue, 18 Aug 2026 00:00:00 +0000

Ecosystems are shaped by communities of microorganisms whose niches and impacts depend on functional profiles influenced by gene gains and losses. Culture-based experiments demonstrate that mobile genetic elements (MGEs) can mediate gene flux, but quantitative understanding of these dynamics in natural systems remains limited. Here we develop and apply a systematic, meta-omic framework to investigate MGEs in a complex natural system using an 8-year soil time series collected at Stordalen Mire, in Sweden’s thawing permafrost margin. In this climate-critical peatland, we identify ~2.1 million MGE recombinases across 89 microbial phyla and assess ecological distributions, affected functions, past mobility and current activity. This revealed an active mobilome that shapes natural genetic diversity via differential impacts on major phyla and affects a wide range of functions, including metabolic genes involved in carbon flux and nutrient cycling. These findings and this analytic framework...

Observation of structures in the J/ψ+ψ(2S) mass spectrum with the ATLAS detector

Tue, 18 Aug 2026 00:00:00 +0000

A search for resonant structures in the mass spectrum is performed using proton-proton collision data at , corresponding to an integrated luminosity of , recorded by the ATLAS experiment at the LHC. The decay channels of and are analyzed. An excess near 6.9 GeV is observed in both channels with a combined significance of . No significant signal is observed near 7.2 GeV, and an upper limit on its yield relative to is provided. A simultaneous fit with the di- channel is carried out under assumptions regarding the resonance interferences, yielding a ratio of the partial decay widths between the and di- channels of for the resonance near 6.9 GeV.

Prey group cohesion mediates the outcome of predator–prey interactions under artificial lighting

Mon, 17 Aug 2026 00:00:00 +0000

Abstract The highest rates of piscivorous predation in the field have been recorded during crepuscular light levels associated with sunrise and sunset or artificial lighting at night (ALAN). Hypothetically, this occurs because, under low‐light conditions, prey lose the ability to visually sense and evade approaching predators, while predators maintain the ability to visually sense and attack prey. However, many prey fishes form social groups, where visually sensing and responding to one another is a key component of anti‐predator behaviours. Thus, for social prey, higher rates of predation under crepuscular conditions could additionally involve the deterioration of prey group behaviours with diminishing light. We conducted a laboratory study exposing groups of predator‐naïve, hatchery‐raised juvenile rainbow trout ( Oncorhynchus mykiss ) to natural‐origin piscivorous largemouth bass ( Micropterus salmoides ) under one of three light treatments: ‘high’—representative of brighter...

Characterizing the Distribution of Oncorhynchus mykiss Genetic Diversity in the Klamath River Basin Before Dam Removal

Sat, 15 Aug 2026 00:00:00 +0000

Genetic assessments serve as powerful tools to evaluate the effects of anthropogenic habitat fragmentation on natural populations. In the Klamath River Basin, construction of four dams from 1912 to 1962 had a profound impact on the distribution of anadromous fishes, blocking access to over 751 river kilometers of critical habitat. To characterize the genetic diversity and connectivity among Oncorhynchus mykiss in the basin prior to the historic removal of the four dams in 2024, we genotyped 2466 samples at 193 presumably neutral and 105 putatively adaptive markers. Using complementary population genetic analyses, we found a clear division between coastal and inland O. mykiss lineages located primarily downstream and upstream of the outlet of Upper Klamath Lake, and little genetic structure associated with dams. Further, we detected distinct inland and coastal genetic lineages upstream of the lake outlet supporting the hypothesis that ancestral inland O. mykiss...

Improving Student Sensory Experiences in the University Library

Thu, 13 Aug 2026 00:00:00 +0000

In 2026, staff at the UC Santa Cruz University Library conducted a project aimed to understand and improve student sensory experiences in library spaces. We recruited 11 undergraduate students to engage in co-design sessions wherein students discussed sensory-related experiences in the library and ideated potential changes that would improve those experiences. These recommended changes were in the areas of communication, facilities, policies, the room booking website, and the equipment and supplies at the library.

This report includes a review of the literature on the impact sensory sensitivities have on undergraduate experiences and an overview on how academic libraries are addressing sensory sensitivities. It also details the methodology researchers used to conduct co-design sessions with students and the changes recommended by the student participants.

The role of species distribution models and multiple data sources in implementing dynamic ocean management

Thu, 13 Aug 2026 00:00:00 +0000

We use the Whale Safe initiative as a case study to investigate the efficacy of species distribution models (SDMs) for dynamic ocean management in a relatively data-rich context. This program combines SDMs, passive acoustic monitoring and opportunistic sightings data to help reduce whale-ship collisions off California, USA. Blue whale SDM predictions were significantly correlated with the in situ observations of whale presence (sightings and passive acoustic detections), suggesting that the model is a reliable source for indicating blue whale presence. We also demonstrated from this multiyear program the value of integrating multiple sources of inference (sightings, acoustics and SDMs) for achieving dynamic management. The results indicated the potential benefit of using validated SDMs in less data-rich regions to support dynamic ocean management when in situ real-time data sources are sporadic or unavailable.

Beyond the Ridge: Rethinking Thermal Windows in Beluga Whales

Thu, 13 Aug 2026 00:00:00 +0000

Beyond the Ridge: Rethinking Thermal Windows in Beluga Whales

Seabed Wide-Angle Reflection Coefficient and Source Radiation Pattern Measurements From a Low-Frequency Multibeam Sonar

Thu, 13 Aug 2026 00:00:00 +0000

In acoustic remote sensing, the seabed frequency-domain reflection coefficient contains significant geoacoustic information, namely the depth and frequency dependence of sediment sound speed, density, and attenuation. Typical reflection measurements are performed with a towed source and/or receivers to obtain a range of seabed reflected angles. It is shown here that the measurements can be performed using a hull-mounted low-frequency multibeam sonar with an offboard fixed or drifting hydrophone. To obtain the reflection coefficient (as well as scattering strength and other quantities of potential interest), the multibeam sonar radiation pattern must be known. Radiation patterns and absolute levels of the Kongsberg SBP29 multibeam sonar are measured and reflection coefficient measurements are presented in two geologically dissimilar environments, the Eel River shelf, CA and the Santa Barbara Basin, CA. The reflection coefficient frequency and angle dependences are explored via...

Key RNA-binding domains in the La protein establish tRNA modification levels in Trypanosoma brucei

Thu, 13 Aug 2026 00:00:00 +0000

The RNA-binding protein La is found in most eukaryotes, and despite being essential in many organisms, its function is not completely clear. Trypanosoma brucei, the causative agent of human African trypanosomiasis, encodes a 'classical' La protein (TbLa) composed of a La-motif, two RNA recognition motifs (RRM1 and RRM2α), a C-terminal short basic motif (SBM), and a nuclear localization signal (NLS). In T. brucei, like in most eukaryotes, position 34 of tRNATyr, -Asp, -Asn and -His is modified with queuosine (Q34). The steady-state levels of queuosine-modified tRNA in the insect form (procyclic) of T. brucei can fluctuate dynamically depending on growth conditions, but the mechanism(s) controlling Q34 levels are not well understood. A well-established function of La is in precursor-tRNA 3'-end metabolism, but in this work, we demonstrate that La also controls Q34-tRNA levels. Individual domain deletions showed that while deletion of La motif or RRM1 causes dysregulation of Q34-tRNA...

UAV-Based Estimation of Fuel Structure and Dynamics in a California Canyon Fire Experiment

Thu, 13 Aug 2026 00:00:00 +0000

UAV-Based Estimation of Fuel Structure and Dynamics in a California Canyon Fire Experiment

Cross-Track Seabed Imaging and Buried Object Detection With a Multibeam Sonar

Thu, 13 Aug 2026 00:00:00 +0000

What lies underneath the ocean floor is of interest to a wide variety of disciplines. The focus here is imaging the upper tens of meters of material beneath the seafloor. The sub-bottom profiler is a valuable tool to that end, producing a 2-D image in depth below the seafloor and along the track of the ship. Geoscientists and engineers are frequently interested in not only the subseabed beneath the ship but also either side or cross-track of the ship. We show an approach to cross-track imaging using a low-frequency multibeam sub-bottom profiler. The main result is the detection of a buried 0.2-m diameter pipeline at a range of nearly 1-km cross-track from the ship in 230-m water depth. This is a swath width coverage of eight times the water depth or nominally an angular range of 76 from nadir. These results have implications not only for buried object detection but also for other potential applications including exploring seabed spatial variability.

"Build a Kit" & "Kit at Home:" Designing Playful, Location-Based Augmented Reality for Individual Emergency Preparedness

Wed, 12 Aug 2026 00:00:00 +0000

Preparing for natural hazards can feel overwhelming or abstract for non-experts. While playful extended reality (XR) has shown potential to support learning around climate-related topics, empirical evidence on its role in natural hazard preparedness remains limited. We employed an iterative, user-centered design approach to develop two Augmented Reality (AR) minigames, Build a Kit and Kit at Home, designed to support emergency preparedness skill-building and real-world action-taking. We evaluated both games in a mixed-methods study (N=22), with participants completing gameplay both independently and during guided community pop-up events at a flood-prone riverfront location, to examine how environmentally situated play shapes user experience. Results indicate that playful AR effectively supported participants' understanding of and confidence in individual emergency preparedness, while locally situated gameplay heightened situational awareness. This work contributes early empirical...

Synthesis of ZrN: Pursuing Phase Purity

Wed, 12 Aug 2026 00:00:00 +0000

In recent years, the superconducting properties of compounds containing lighter elements have proven to be a promising area of research. For example, highly pressurized hydride superconductors were predicted and experimentally shown to have extremely high superconducting phase transition temperatures. This motivates investigations of other light element superconductors: e.g., those containing nitrogen. Here we report results for the synthesis of bulk polycrystalline zirconium nitride. This was done by reacting zirconium under a nitrogen atmosphere using two separate methods: (i) an electrical arc furnace and (ii) an induction furnace. This is followed by crushing and annealing of the resulting specimen under a nitrogen atmosphere. Powder x-ray diffraction measurements confirm that the crystalline structure matches that of ZrN. Temperature dependent electrical transport measurements reveal metallic behavior for high temperatures with a superconducting transition at Tc = 10.4 K,...