California Institute of Technology

Tracing the Cosmic Origins: Machine Learning Reconstruction of the Primordial Density Field from EoR Observations

Abstract Reconstructing the initial conditions of the Universe from late-time tracers would unlock cosmological information buried by non-linear structure formation and astrophysics. We reconstruct the initial density field corresponding to z = 300, with its linear amplitude extr...

Enantioselective Reactions of Palladium Enolate Intermediates: Beyond Allylic Alkylation

Conspectus The enantioselective Pd-catalyzed allylic alkylation reaction has proven to be an incredibly powerful and versatile methodology for the construction of stereoenriched building blocks bearing all-carbon quaternary centers. We have contributed to this field by investigat...

Mechanoadaptive nanowire viscoplastic composites with strain-enhanced conductivity for reprocessable bioelectronic interfaces

Bioelectronic interfaces must mechanically conform and adapt to biological tissues while maintaining stable electrical performance during motion and deformation. Existing soft conductors, however, often couple mechanical strain to electrical resistance, accumulate interfacial str...

Death and chemotaxis: Bacterial chemotaxis enables collective escape from phage predation

Bacteriophages (“phage”) are viruses that prey on bacteria in diverse environments, from biological tissues to soils. In many of these environments, bacterial hosts are constantly migrating, yet how bacterial migration is influenced by phage predation remains poorly understood. U...

Tipping point forecasting in nonstationary dynamics on function spaces

Tipping points are abrupt, drastic, and often irreversible changes in the evolution of nonstationary and chaotic dynamical systems. For instance, increased greenhouse gas concentrations are predicted to lead to drastic decreases in low cloud cover, referred to as a climatological...

LIGO Detector Characterization in the Second and Third Parts of the Fourth Observing Run

Abstract LIGO detector characterization efforts enabled the confident detection of gravitational waves from hundreds of compact binary coalescences during the fourth observing run. Reliable production of high quality detector data and rapid noise mitigation efforts allow the extr...

Fungal frontiers for sustainability: unlocking the hidden kingdom

Fungi have repeatedly delivered transformative advances across industries, from medicine to food to materials, yet these breakthroughs have emerged from a narrow base of organisms and well-studied systems. Although mycology has taken a big leap forward in the past decades because...

Data-Driven Reduced-Complexity Modeling of Fluid Flows: A Community Challenge

We introduce a community challenge designed to facilitate direct comparisons between data-driven methods for compression, forecasting, and sensing of complex aerospace flows. The challenge is organized into three tracks that target these complementary capabilities: compression (c...

Near-Flatband Resonances in Bilayer Moire Superlattices for Visible-to-Infrared Meta-Optics

Abstract Flat photonic bands enable extreme light confinement, slow-light effects, and angle-robust resonances that are valuable for meta-optics and integrated photonics. Here we report the design, fabrication, and experimental characterization of 1D Moiré superlattices formed b...

Scalable Gaussian Process for Learning Non‐Ergodic Ground Motion Model From Physics‐Based Simulations With Application to Power Infrastructure Assessment

ABSTRACT This study presents the development and application of a scalable non‐ergodic ground motion model (NGMM) for the Los Angeles area. The NGMM is trained and validated on physics‐based simulated ground‐motion data from a recent Statewide California Earthquake Center (SCEC)...

Compositional control of magnetocaloric performance and energy losses in LaFe11.5−( x + y )Co x Ni y Si1.5 alloys

Alloys of La(Fe,Si)13 with transition metal substitutions are promising magnetocaloric materials. Here, we systematically investigate Co and Ni substitution in LaFe11.5−(x+y)CoxNiySi1.5 to tune the magnetic and structural properties and assess the resulting impacts on magnetocalo...

Varying Mechanisms Dominate Formate Formation in Electrochemical CO2 Reduction on Cu, Au, and Pb: A Constant Potential DFT-Based Microkinetic Analysis

Abstract Electrochemical CO2 reduction offers a route to convert renewable electricity into fuels and chemicals while closing the anthropogenic carbon cycle. However, the technology struggles to surpass the lab scale as it is limited by low selectivity and energy efficiency. Thes...

A fast radio burst at redshift 2, three billion years after the Big Bang

Fast radio bursts (FRBs) are millisecond-duration radio transients from extragalactic sources. Their frequency and polarization properties are affected by plasma and magnetic fields along the line of sight to Earth. We report radio observations of FRB 20240304B and near-infrared...

Improved estimation of net ecosystem CO 2 exchange over North America using LSTM-based flux upscaling (2001–2021)

Accurate estimation of regional-scale terrestrial carbon budgets is of great importance but remains challenging. With particular advantages, the Long Short-Term Memory (LSTM) network method shows potential for improving regional carbon budget upscaling estimations. Here, using LS...

BioForge: A Fast and Safe Macromolecular Structure Preparation Library in Rust

Abstract Summary BioForge is the first macromolecular structure preparation library for Rust, complementing sequence-analysis libraries such as Rust-Bio with cleaning, geometry-based missing-atom repair, protonation, and solvation as a force-field-agnostic preprocessing stage. Ac...

Soundboard Fractures in the Bent Side/Cheek Corner of Harpsichords

The following study is the result of an investigation over several years, seriously because the 2025 Eaton fire interfered substantially. It was prompted by a comment in the Jackrail Forum communications by Domenico Statuto regarding an internet publication by Geert Karman (see l...

Electrochemical Hydroformylation with a Homogeneous Rhodium Catalyst

Abstract Electrochemical hydroformylation is an attractive pathway to synthesize aldehydes at ambient conditions using electrons sourced from renewable energy as a reductant instead of hydrogen gas sourced from energy-intensive steam methane reforming. However, previously reporte...

Chemoenzymatic Synthesis of ( E,E,Z )-Humulene-Derived Natural Products

Abstract Meroterpenoid natural products derived from the 11-membered macrocycle humulene are of great interest due to their potent biological activities and intricate architectures. Whereas molecules derived from the most available (E,E,E)-humulene isomer have been thoroughly inv...

Generalized Nonlinear Bayesian Pulsar Timing with ENTERPRISE

Abstract We use the Bayesian methods in the ENTERPRISE package to examine the fully general parameterization of pulsar timing models in tandem with noise. We investigate four pulsars, PSRs J1600–3053, J2043+1711, J0740+6620, and J1640+2224, through the lens of Bayesian timing. We...

Transcription pause and elongation regulators mediate somatic hypermutation

Somatic hypermutation (SHM) creates point mutations in the variable regions of immunoglobulin genes in activated B cells to support antibody affinity maturation1. SHM is initiated by activation-induced deaminase (AID), and the single-stranded DNA substrate of this cytosine deamin...