Proceedings of the National Academy of Sciences
Articles in this Issue
A molecular lattice reinforces the sperm head–tail junction
Temperature-dependent feedbacks drive the pattern of Antarctic temperature change
Antarctica is an important component of the Earth’s climate system. Here we investigate temperature change in Antarctica across a range of timescales, from millennial to orbital, over the last...
MHC-I diversity enables rapid adaptation during a viral pandemic in wild rabbit populations
Emerging diseases can have devastating consequences for wild species, with long-term effects depending on the ability of the host to evolve resistance. Here, we show that major histocompatibility comp...
A brain circuit of bidirectional modulation of social and nonsocial cognition by androgens and estrogens in male mice
Androgens and estrogens rapidly influence brain function and behaviors critical to social species, including social recognition, which is essential for group living and modulating social interactions....
Discovering regularity and mechanisms of word sense acquisition in childhood
How does language use inform the emergence of word meanings in early life? Prior work in developmental psychology and the cognitive sciences typically focuses on studying word acquisition in children...
Emergent anisotropic three-phase order in critically doped superconducting diamond films
Two decades since its discovery, superconducting heavily boron-doped diamond (HBDD) still poses fundamental questions that need to be answered to unlock its full potential for quantum applications. We...
2024 global temperature record is consistent with model-predicted warming
We employ a semiempirical approach combining climate model simulations and observational temperatures to assess the likelihood of recent global temperature records. Monte Carlo simulations are used to...
Surrounding landscapes shape species persistence in fragmented forests
Do negative social ties accelerate aging in adults, or does aging erode social ties?
Sperm, egg, and embryo proteins critical for genetic adaptation of herring to low salinity in the Baltic Sea
How species genetically adapt to new environments is a central question in evolutionary biology. Here whole-genome sequencing combined with functional analysis is used to dissect how Atlantic herring,...
Choice of cardioplegia influences metabolomics of human cardiac tissue
Cardioplegia is often used prior to acquisition of human cardiac tissue to minimize warm ischemia time, which can severely confound studies of cardiac metabolism. However, there are several choices of...
Early evidence for a stable and flexible foraging niche in the evolution of <i>Homo</i>
Major evolutionary transitions in Homo (e.g., increased brain size, complex social behavior) are linked to reliance on high-quality foods. Increased meat consum...
Soil temperature fluctuations modulated millet agriculture evolution in Neolithic East Asia
Millet agriculture was foundational to the emergence of complex societies in Neolithic East Asia, yet the environmental mechanisms shaping its spatiotemporal development remain unresolved. Here, we pr...
Tracing the origins and recurrence of the South Atlantic Anomaly: A 2000-year absolute paleointensity record from central South America
A robust characterization of geomagnetic field strength in the Southern Hemisphere over the past millennia is critical for understanding the (multi)centennial evolution of the South Atlantic Anomaly (...
Metabolic engineering of <i>Escherichia coli</i> for the biosynthesis of nylon 6 and nylon 6,6 monomers
Hexamethylenediamine (HMD), adipic acid, and ε-caprolactam (ε-CL) are essential C6 monomers used in the production of nylon 6,6 and nylon 6. Developing sustainable, bio-based routes to these compounds...
Disparate social structures are underpinned by distinct social rules across a primate radiation
Over six decades of research on wild baboons and their close relatives (collectively, the African papionins) have uncovered substantial variation in their behavior and social systems. While most papio...
The pig in the python: US decennial labor flows and economic opportunity, 1910–2040
This analysis revisits the relative cohort size hypothesis proposed by demographer Richard Easterlin in the 1960s. Easterlin argued that the economic and social prospects of a generation are influence...
PARP1 deficiency mitigates amyloid pathology, neurodegeneration, and cognitive decline in a familial Alzheimer’s disease model
Poly(ADP-ribose) (PAR) polymerase 1 (PARP1) has been implicated in DNA damage responses and neuroinflammation in Alzheimer’s disease (AD), yet its role in amyloid-beta (Aβ) pathology remains unclear....
Scientific authority cues increase the spread of misinformation
Despite extensive efforts to curb misinformation, it continues to spread on social media platforms. Research indicates that people rarely share content they know is false, rather, they do so unintenti...
Blue- versus green-absorbing anion channelrhodopsins, essential tools in optogenetics, differ fundamentally in gating mechanisms
The genomes of many protists encode at least one pair of spectrally distinct cation or anion channelrhodopsins. Two cation channelrhodopsins (CCRs) initiate different transduction cascades in...
Selective divergence between Grokipedia and Wikipedia articles
The launch of Grokipedia, an AI-generated encyclopedia developed by xAI, was presented as a response to perceived ideological and structural biases in Wikipedia, with the goal of producing more “truth...
Multiscale fatigue crack initiation in hierarchical additively manufactured alloys
Bioinspired hierarchical microstructures offer a route toward engineered fatigue resistance in additively manufactured alloys. However, it remains unclear how discrete structural constituents independ...
Streamlined optical training of large-scale modern deep learning architectures with direct feedback alignment
Modern deep learning relies nearly exclusively on dedicated electronic hardware accelerators. Photonic approaches, with low consumption and high operation speed, are increasingly considered for infere...
NAT10/ac <sup>4</sup> C drives intrahepatic cholangiocarcinoma by suppressing transposable elements via chromatin remodeling
Intrahepatic cholangiocarcinoma (ICC) poses a significant clinical challenge due to its insidious onset, aggressive biological behavior, and propensity for early metastasis, contributing to a dismal 5...
Regulated development of cannibalistic supergiant cells in the ciliate <i>Euplotes gigatrox</i>
Virtually all paradigms in developmental biology apply to differentiating cells and tissues within multicellular animals and plants. However, unicellular eukaryotes, which must simultaneously perform...