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Table Of Contents Page, PNAS Volume 119, Number 47

Physical Sciences

Enhancing science education in developing countries has been a focal point of many studies and efforts, but reform has mainly been driven by top-down approaches that often face impediments. A shift to active learning pedagogies can potentially address ...
As a ubiquitous paradigm of instabilities and mixing that occur in instances as diverse as supernovae, plasma fusion, oil recovery, and nanofabrication, the Rayleigh–Taylor (RT) problem is rightly regarded as important. The acceleration of the fluid ...
Climate change necessitates a global effort to reduce greenhouse gas emissions while adapting to increased climate risks. This broader climate transition will involve large-scale global interventions including renewable energy deployment, coastal ...
Magnetic materials are essential for energy generation and information devices, and they play an important role in advanced technologies and green energy economies. Currently, the most widely used magnets contain rare earth (RE) elements. An outstanding ...
The input of the soluble micronutrients iron (Fe) and/or manganese (Mn) by mineral dust stimulates net primary productivity in the Fe/Mn-deficient Southern Ocean. This mechanism is thought to increase carbon export, thus reducing atmospheric CO2 during ...
We analyze the knowledge acquired by AlphaZero, a neural network engine that learns chess solely by playing against itself yet becomes capable of outperforming human chess players. Although the system trains without access to human games or guidance, it ...
Trends in extreme 100-y events of temperature and rainfall amounts in the continental United States are estimated, to see effects of climate change. This is a nontrivial statistical problem because climate change effects have to be extracted from “noisy” ...
Climate-model simulations exhibit approximately two times more tropical tropospheric warming than satellite observations since 1979. The causes of this difference are not fully understood and are poorly quantified. Here, we apply machine learning to ...
We report the observation of the smectic AF, a liquid crystal phase of the ferroelectric nematic realm. The smectic AF is a phase of small polar, rod-shaped molecules that form two-dimensional fluid layers spaced by approximately the mean molecular ...
Nearfield spectroscopic imaging techniques can be a powerful tool to map both cellular ultrastructure and molecular composition simultaneously but are currently limited in measurement capability. Resonance enhanced (RE) atomic force microscopy infrared (...
Consider the tight binding model of graphene, sharply terminated along an edge l parallel to a direction of translational symmetry of the underlying period lattice. We classify such edges l into those of “zigzag type” and those of “armchair type,” ...
The main mathematical result in this paper is that change of variables in the ordinary differential equation (ODE) for the competition of two infections in a Susceptible–Infected–Removed (SIR) model shows that the fraction of cases due to the new variant ...
Providing affordable and nutritious food to a growing and increasingly affluent global population requires multifaceted approaches to target supply and demand aspects. On the supply side, expanding irrigation is key to increase future food production, yet ...
Second harmonic generation microscopy (SHG) is generally acknowledged as a powerful tool for the label-free three-dimensional visualization of tissues and advanced materials, with one of its most popular applications being collagen imaging. Despite the ...

Biological Sciences

The formation of cell polarity is essential for many developmental processes such as polar cell growth and spatial patterning of cell division. A plant-specific ROP (Rho-like GTPases from Plants) subfamily of conserved Rho GTPase plays a crucial role in ...
Human history is written in both our genes and our languages. The extent to which our biological and linguistic histories are congruent has been the subject of considerable debate, with clear examples of both matches and mismatches. To disentangle the ...
Autophagy is a cellular catabolic pathway generally thought to be neuroprotective. However, autophagy and in particular its upstream regulator, the ULK1 kinase, can also promote axonal degeneration. We examined the role and the mechanisms of autophagy in ...
Anatomy of the first flying feathered dinosaurs, modern birds and crocodylians, proposes an ancestral flight system divided between shoulder and chest muscles, before the upstroke muscles migrated beneath the body. This ancestral flight system featured ...
Legumes establish endosymbiotic associations with nitrogen-fixing rhizobia, which they host inside root nodules. Here, specific physiological and morphological adaptations, such as the production of oxygen-binding leghemoglobin proteins and the formation ...
Humans are argued to be unique in their ability and motivation to share attention with others about external entities—sharing attention for sharing’s sake. Indeed, in humans, using referential gestures declaratively to direct the attention of others ...
Senescence in pancreatic beta cells plays a major role in beta cell dysfunction, which leads to impaired glucose homeostasis and diabetes. Therefore, prevention of beta cell senescence could reduce the risk of diabetes. Treatment of nonobese diabetic (NOD)...
In the early stages of meiosis, maternal and paternal chromosomes pair with their homologous partner and recombine to ensure exchange of genetic information and proper segregation. These events can vary drastically between species and between males and ...
Lyme spirochetes have coevolved with ticks to optimize transmission to hosts using tick salivary molecules (TSMs) to counteract host defenses. TSMs modulate various molecular events at the tick–host interface. Lymphotoxin-beta receptor (LTβR) is a vital ...
RNA-binding proteins contain intrinsically disordered regions whose functions in RNA recognition are poorly understood. The RNA chaperone Hfq is a homohexamer that contains six flexible C-terminal domains (CTDs). The effect of the CTDs on Hfq’s integrity ...
The complex interplay between genetics, culture, and environment forms an individual’s biology, influencing their behavior, choices, and health. However, to what extent information derived from this intertwined network could be quantitatively summarized ...
Homologous enzymes with identical folds often exhibit different thermal and kinetic behaviors. Understanding how an enzyme sequence encodes catalytic activity at functionally optimal temperatures is a fundamental problem in biophysics. Recently it was ...
Mitochondria have their own DNA (mtDNA), which encodes essential respiratory subunits. Under live imaging, mitochondrial nucleoids, composed of several copies of mtDNA and DNA-binding proteins, such as mitochondrial transcription factor A (TFAM), actively ...
Cytoplasmic incompatibility (CI) is the most common reproductive manipulation produced by Wolbachia, obligately intracellular alphaproteobacteria that infect approximately half of all insect species. Once infection frequencies within host populations ...
The increase of CO2 emissions due to human activity is one of the preeminent reasons for the present climate crisis. In addition, considering the increasing demand for renewable resources, the upcycling of CO2 as a feedstock gains an extensive importance ...
Neural computational power is determined by neuroenergetics, but how and which energy substrates are allocated to various forms of memory engram is unclear. To solve this question, we asked whether neuronal fueling by glucose or lactate scales differently ...
Severe COVID-19 is characterized by a prothrombotic state associated with thrombocytopenia, with microvascular thrombosis being almost invariably present in the lung and other organs at postmortem examination. We evaluated the presence of antibodies to ...
Somatic copy number alterations (SCNAs), generally () losses containing interferons and interferon-pathway genes, many on chromosome 9p, predict immune-cold, immune checkpoint therapy (ICT)-resistant tumors (); however, genomic regions mediating these ...
Fungi are central to every terrestrial and many aquatic ecosystems, but the mechanisms underlying fungal tolerance to mercury, a global pollutant, remain unknown. Here, we show that the plant symbiotic fungus Metarhizium robertsii degrades methylmercury ...
Topological analysis of protein residue networks (PRNs) is a common method that can help to understand the roles of individual residues. Here, we used protein kinase A as a study object and asked what already known functionally important residues can be ...

Social Sciences

There are long-standing concerns that peer review, which is foundational to scientific institutions like journals and funding agencies, favors conservative ideas over novel ones. We investigate the association between novelty and the acceptance of ...
Discrimination is not only an objective fact but also a subjective judgment. While extensive research has studied discrimination as an objective fact, we study the judgment of discrimination and show that it is malleable while holding objective ...
For countries to rapidly decarbonize, they need strong leadership, according to both academic studies and popular accounts. But leadership is difficult to measure, and its importance is unclear. We use original data to investigate the role of presidents, ...
Uterine leiomyoma is the most common tumor in women and causes severe morbidity in 15 to 30% of reproductive-age women. Epidemiological studies consistently indicate a correlation between leiomyoma development and exposure to endocrine-disrupting chemical ...
Anti-Black racism remains a pervasive crisis in the United States. Racist social systems reinforce racial inequalities and perpetuate prejudicial beliefs. These beliefs emerge in childhood, are difficult to change once entrenched in adolescence and ...
Online reviews significantly impact consumers’ decision-making process and firms’ economic outcomes and are widely seen as crucial to the success of online markets. Firms, therefore, have a strong incentive to manipulate ratings using fake reviews. This ...
About one in six Asian Americans have fallen victim to anti-Asian racism during the COVID-19 pandemic [J. Lee, K. Ramakrishnan, aapidata.com/blog/discrimination-survey-2022/]. By examining anti-Asian racism in the United States primarily as a domestic ...
A multimethod archaeometry study (zooarchaeological, isotopic, ancient DNA, paleobotanical, and radiocarbon dating) of a spider monkey sacrificed in the ceremonial center of Teotihuacan, Mexico (1 to 550 CE) is interpreted as a diplomatic gift exchange ...

Perspective

Traditional general circulation models, or GCMs—that is, three-dimensional dynamical models with unresolved terms represented in equations with tunable parameters—have been a mainstay of climate research for several decades, and some of the pioneering ...

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