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Susceptible host dynamics explain pathogen resilience to perturbations
No full textInterventions to slow the spread of SARS-CoV-2 significantly disrupted the transmission of other pathogens. As interventions lifted, whether and when human pathogens would eventually return to their prepandemic dynamics remains to be answered. Here, we present a framework for estimating pathogen resilience based on how fast epidemic patterns return to their prepandemic dynamics. By analyzing time series data from Hong Kong, Canada, Korea, and the United States, we quantify the resilience of common respiratory pathogens and further predict when each pathogen will eventually return to its prepandemic dynamics. Our predictions are able to distinguish which pathogens should have returned already, and deviations from these predictions reveal long-term impacts of pandemic perturbations. We find a faster rate of susceptible replenishment underlies pathogen resilience and sensitivity to both large and small perturbations. Overall, our analysis highlights the persistent nature of common respiratory pathogens compared to vaccine-preventable infections, such as measles.</p
Restoring institutional confidence in backsliding democracies: Evidence from Mexico
No full textDeclining confidence in public institutions afflicts many democracies, a trend apparently exacerbated by backsliding leaders. These are leaders who gradually undermine the institutions that sustain democratic competition and accountability. Does the rhetoric of backsliders undermine the public’s confidence in the institutions under attack and can rebuttals of presidential diatribes restore this confidence? We explore the impact of backsliding leaders’ anti-institutional rhetoric in the context of Mexico. With text-as-data analyses, we demonstrate the harshness of President Andrés Manuel López Obrador’s (2018–2024) anti-institutional diatribes against the agency that oversees national elections. With survey experiments, we demonstrate that these diatribes can indeed undermine public confidence. Yet our research also uncovers the potential for rebuttals to restore confidence. Counternarratives offered by organizations viewed as above the fray of Mexican politics restored public confidence—surprisingly, even among the president’s supporters. Our findings suggest strategies for breaking out of the cage of intense partisanship and countering democracy-degrading rhetoric. Though presidential haranguing of democratic institutions can have a powerful effect, there remains room for public confidence to be restored by more positive accounts.</p
-parity violation and 8 TeV four-jet events at the LHC
No full text The CMS Collaboration at the Large Hadron Collider (LHC) has observed two four-jet events with a total invariant mass of about 8 TeV; within each event, the jets can be paired into two dijets with invariant masses of 2 TeV each. These are extremely rare events due to the large invariant mass, which implies a very small QCD background, as well as to the dijet structure, which makes it prone to an interpretation in terms of a heavy resonance decaying into two lighter ones. We investigate the possible interpretation of these events in terms of supersymmetry with a single baryon-number and R -parity violating term. In this particular scenario, the lighter resonances are identified with the right-handed squarks of the first generation, while the heavy one is interpreted in terms of a down-squark of the second or third generation. We discuss the constraints that shape this interpretation and outline a well-defined scenario for its realization. The resulting predictions can be scrutinized with forthcoming LHC data.</p
Multiscale Characterization of Biologically Relevant Thin Sheet Instabilities
No full textThin sheets are present in all areas of life, biologically relevant in various systems and scales from cell membranes to multi-layered tissues. Though compositionally very different, soft matter thin sheets all respond to imposed strains through deformation and mechanical instability. The type of resultant deformation and instability is dictated by the competing energetic costs of in-plane and out-of-plane deformation. The relative energetic costs of these two deformation modes are highly dependent on properties of the thin sheet such as material behavior, thickness, and geometric constraints. While existing theoretical models for thin sheet instabilities assume classic elasticity, infinitely thin sheets, and inextensibility, these assumptions often lack the complexity needed to capture the observed behavior of biological thin sheets. Utilizing continuum solid mechanics and elasticity, this dissertation probes the effects of adaptive material behavior, physically relevant thicknesses, and surgically motivated geometric constraints on emergent thin sheet mechanical deformations and instabilities. This work employs finite element simulations to model the mechanical response of biological thin sheets undergoing external loading and geometric manipulation, with the ultimate goal of developing, questioning, and building upon theoretical and computational frameworks of thin sheet mechanical response
Characterizing the Roman Grism Redshift Efficiency of Type Ia Supernova Host Galaxies for the High-latitude Time-domain Survey
No full textThe High-latitude Time-domain Survey (HLTDS) for the Nancy Grace Roman Space Telescope (Roman) will discover thousands of high-redshift Type Ia supernovae (SNe Ia) to set generation-defining cosmological constraints on dark energy. To construct the Roman SN Hubble diagram, a strategy to obtain redshifts must be determined. While the nominal HLTDS will use only the Roman prism, in this work, we consider the utility of the Roman grism observations from overlap with the High-latitude Wide-area Survey for SN Ia cosmology. We determine a galaxy grism redshift recovery rate by simulating dispersed grism images and measuring redshifts with the Grizli software, obtaining an H-band 50% redshift recovery at magnitude 20.61 and 90% recovery at magnitude 19.27. To estimate the total number of spectroscopic redshifts expected for Roman SN cosmology, we also consider a Roman prism SN redshift efficiency and a ground-based telescope redshift efficiency for host galaxies. We apply these redshift efficiencies to SN Ia catalog-level simulations and predict that ∼6800 SNe will have an SN or host spectroscopic redshift. Second, we evaluate the size of potential systematics related to modeling the grism redshift efficiency by considering the impact of additional dependences on stellar mass and host-galaxy color. We estimate the largest potential size of this systematic to be 0.0066 ± 0.002 and −0.0266 ± 0.0079, roughly 42.9% and 49.6% of the statistical uncertainty, for w0 and wa, respectively. Lastly, we consider the effects of assuming different redshift sources on the optimization of the HLTDS survey strategy by measuring relative changes to the dark energy figure of merit
Field-Level Cosmological Inference
No full textModern cosmological surveys, from cosmic microwave background experiments to optical galaxy surveys, amass data at the petabyte scale. Prior to inference, these data are typically compressed into low-dimensional summary statistics, discarding substantial information, including non-Gaussian features, and complicating multiprobe analyses. I present an emerging opportunity to reimagine cosmological inquiry through field-level inference (FLI). FLI replaces summary statistics with a forward model that directly compares simulated observables to data. This formulation preserves map-level information and naturally unifies map-making, multiprobe combination, and parameter inference, but it leads to high-dimensional, non-Gaussian posteriors whose structure must be understood and controlled. I introduce field-level inference as a practical methodology spanning theory, modeling, and applications. I analyze the mathematical structure of FLI in analytically tractable regimes; extend FLI to weak gravitational lensing with controlled systematics; develop a fast, differentiable forward model that evolves and ray-traces through nonlinear matter structures; and introduce a flexible field-level correction for baryonic feedback effects. I also discuss adjacent topics, including a map-level test of the isotropy of cosmic expansion and the decontamination of atmospheric foregrounds in ground-based CMB data. Collectively, these results demonstrate how the field-level approach can be made accurate, computationally feasible, and robust for cosmological inference
Artificial Intelligence and the Interpretation of the Past
No full textArtificial intelligence is reshaping the contemporary world. Trickling deeper into archaeology and history, these technological changes will influence how the past is written about and visualized. Through the evaluation of text and images generated using AI, this article considers the systemic biases present in reconstructed archaeological scenes. We draw on advances in computer science, running large-scale, computational analyses to evaluate patterns in content. We present a case study examining Neanderthal behavior, juxtaposing published archaeological knowledge with images and text made using AI. Our study reveals a low correspondence between scientific literature and artificially intelligent material, which reflects dated knowledge and cultural anachronisms. Used to identify patterns in (mis)representations of the past, the methodology can be applied to understand the distance between scholarly knowledge and any domain of content generated using AI, across any archaeological time depth and beyond the discipline. La inteligencia artificial está transformando el mundo contemporáneo. Al expandirse hacia la arqueología y la historia, estos cambios tecnológicos influirán en la manera en que se escribe y se visualiza el pasado. Mediante la creación de textos e imágenes, generados por inteligencia artificial, este artículo examina los sesgos sistémicos presentes en la reconstrucción de escenas arqueológicas. Desarrollamos enfoques cada vez más frecuentes en la arqueología que se basan en avances de las ciencias computacionales, realizando análisis computacionales a gran escala para evaluar patrones en textos e imágenes. Presentamos un estudio de caso sobre el comportamiento neandertal, en el que contrastamos el conocimiento arqueológico publicado con imágenes y textos generados por IA. Nuestro estudio revela una baja correspondencia entre la literatura científica y los contenidos producidos mediante inteligencia artificial, los cuales reflejan conocimientos desactualizados y anacronismos culturales. Esta metodología, empleada para identificar patrones en las (mal)representaciones del pasado, puede aplicarse para comprender la distancia entre el conocimiento académico y cualquier tipo de contenido generado con IA, en cualquier profundidad temporal arqueológica e incluso más allá de la disciplina.</p
Re-Understanding the Deceased Aspect of Amenope in the Decade Festival Through Comparison with Osiris
No full textThis thesis aims to reevaluate the deceased aspect of Amenope in the Decade Festival, which was celebrated in Thebes every ten days from the Third Intermediate Period to the Greco-Roman period. In this festival, Amenope appeared at Luxor and crossed the river to the Small Temple at Medinet Habu to symbolically pour libations for his fathers, Kematef and the Ogdoad. While previous studies focused more on the role of Amenope as a living son, this paper stresses the decease aspect of Amenope and compares him with Osiris. By analyzing the shared astral connotations of the Decade Festival and other cultic rites of the decans, this paper argues that the Decade Festival was celebrated at sunrise every ten days together with the heliacal risings of the decans. Amenope is thus associated with Osiris, whose resurrection is also connected with the reborn decans. This paper then parallels Amenope with Osiris by analyzing some textual evidence. The phrase di tp ⸗ff, “to show his head,” is the focus of the discussion since it and some expressions similar to it are used to describe both Amenope and Osiris. This paper further confirms the parallelism between Amenope and Osiris by displaying the similarities between the veiled form of Amenope and the image of Osiris in his Awakening scene. This paper thus argues that the veiled form of Amenope depicts the resurrection of Amenope at the beginning of every decade when he is transformed like the Osiris from his deceased aspect to his living aspect
Fecal butyrate and deoxycholic acid quantitation for rapid assessment of the gut microbiome
No full textThe intestinal microbiome is composed of myriad microbial species with impacts on host health that are mediated by the production of metabolites. While loss of bacterial species and beneficial metabolites from the fecal microbiome is associated with development of a range of diseases and medical complications, there are currently no clinical diagnostic tests that rapidly identify individuals with microbiome deficiencies. This method aims to rapidly quantify fecal concentrations of butyrate and deoxycholic acid, as depletion of these two metabolites are associated with adverse clinical outcomes and result from the loss of a subset of health-associated bacterial species. We present a rapid diagnostic screen based on 3-nitrophenylhydrazine derivatization and ultrahigh-performance liquid chromatography-mass spectrometry that measures fecal butyrate and deoxycholic acid concentrations as markers of microbiome function. A matrix-matched calibration curve was developed using a simulated fecal mixture to optimize accuracy and facilitate adherence to clinical laboratory regulations. The assay resulted in an analytical measurement range from 4.30–3030 µM (LLOQ = 3.71 µM) for butyrate and from 0.9–64.9 µM (LLOQ = 0.7 µM) for deoxycholic acid. Precision evaluation demonstrated a coefficient of variation <15% at all quality control levels tested. The rapid liquid chromatography-mass spectrometry screen can be performed in under an hour from extraction to provision of quantitative results, enabling the rapid identification of patients with defective microbiome function.</p
How does the client’s risk profile affect their price sensitivity for auditors?
No full textThis paper examines whether client risk profile moderates audit fee sensitivity in auditor selection. Using a pre-cleaned firm-year dataset of 5,008 U.S. publicly traded firms in fiscal years 2010-2011, we estimate a mixed logit model with a composite risk-fee interaction that allows fee sensitivity to vary across clients. The result shows that a higher audit fee significantly reduces the chance of an auditor being chosen (−3.510, p < 0.001) and risk-fee interaction is positive and significant (1.161, p < 0.001), which means riskier firms are less sensitive to price. The large SD on fee (SD = 3.59) and risk-fee interaction (SD = 5.77) shows substantial heterogeneity among clients. A size-split robustness check further suggests that the risk-related moderation in fee sensitivity is concentrated among larger firms, while the interaction is not statistically significant among smaller firms