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Republicans are flagged more often than Democrats for sharing misinformation on X’s Community Notes

We use crowd-sourced assessments from X’s Community Notes program to examine whether there are partisan differences in the sharing of misleading information. Unlike previous studies, misleadingness here is determined by agreement across a diverse community of platform users, rather than by fact-checkers. We find that 2.3 times more posts by Republicans are flagged as misleading compared to posts by Democrats. These results are not base rate artifacts, as we find no meaningful overrepresentation of Republicans among X users. Our findings provide strong evidence of a partisan asymmetry in misinformation sharing which cannot be attributed to political bias on the part of raters, and indicate that Republicans will be sanctioned more than Democrats even if platforms transition from professional fact-checking to Community Notes.

Mesoporous Enhanced Heterostructured Halide Solid Electrolytes with High Air Stability and High Abundance for Sustainable Sodium Metal Batteries

Abstract Chlorides and fluorides solid‐state electrolytes (SEs) exhibit contrasting extremes in ionic conductivity and moisture sensitivity. In light of these conflicting factors, we introduce a NaCl‐based SE reinforced by mesoporous α‐AlF 3 (denoted as HS‐AlF 3 ), leading to a heterostructure halide architecture, designated as NHxy (where x/y represents the mass ratio of NaCl to HS‐AlF 3 ). The high dispersion of NaCl and HS‐AlF 3 during mechanochemical process enables the generation of defective and amorphous structures and nanodomains in NHxy along with F‐Cl anion substitution effect at grain boundaries. These factors collectively promote Na ion transport in NHxy, especially along the NaCl based heterostructures with AlF 3 and NaF. This class of SEs achieves the high ionic conductivity approaching 10 −4 S cm −1 at 30 °C. Specifically, NH54 exhibits excellent long‐term air stability at 35% relative humidity, maintaining high ion conductivity without degradation. The raw material cost of this Na‐based electrolyte is less than $10 USD kg −1 when considering the production in a large scale. The corresponding Na//Na symmetric cells demonstrate the stable cycling for at least 1000 h at 0.1 mA cm − 2 . The Na//Na 3 V 2 (PO 4 ) 3 cells assembled with the NH54 after air exposure exhibit the remarkable longevity, sustaining over 400 cycles at 60 °C. The conversion‐type Na/NH54/FeF 3 cells deliver a high capacity of 500 mAh g −1 . This work opens the new pathways for inorganic SEs with enhanced economic value, ion conductivity, air stability and suitability for energy‐dense conversion reaction batteries.

An endosymbiotic origin of the crimson pigment from the lac insect

Symbioses with microorganisms expand the genetic and metabolic repertoire of many insects. The lac insect Kerria lacca (Hemiptera: Sternorrhyncha) is a phloem-feeding scale insect that is brightly colored due to the presence of natural polyhydroxy-anthraquinone pigments called laccaic acids. The deep red pigments possibly provide defense against pathogens and predators and are commercially important as dyes in textiles, lacquerware, and cosmetics. Laccaic acids are categorized as polyketides comprising an anthraquinone backbone decorated with tyrosine or its derivatives. However, the genetic basis of these pigments remains unknown, as insects are not known to produce aromatic polyketides or tyrosine de novo. Here, we sequence the genome of the lac insect and its two endosymbionts— Wolbachia and a hitherto unidentified, transovarially transmitted yeast-like symbiont (YLS). We found no evidence for the host or Wolbachia to be able to synthesize the pigments. The pigments and their precursors were also not detected in the host plant. Genomic, transcriptomic, and metabolomic analyses combined with fluorescence microscopy identified and characterized YLS as the sole producer of the pigment’s polyketide backbone and tyrosine moiety, demonstrating an endosymbiotic origin of the lac pigments. A nonreducing polyketide synthase gene cluster encoding the laccaic acid backbone was identified. Furthermore, the YLS genome encoded essential amino acids and vitamins that are deficient in the insect’s phloem diet. Experimental fungicide-treated insects exhibited reduced concentrations of laccaic acids and tyrosine, along with decreased body size and weight, indicating a mutualistic association between the lac insect and its YLS.

Heightened interest in the human X and Y chromosomes

Constructions of Biaryl‐Bridged Macrocycles Through Phosphine‐Ligand‐Controlled Switch of Selectivity Between Intra‐ and Intermolecular Cyclizations

Abstract The rigid biaryl‐bridged macrocycles serve as core scaffolds in numerous bioactive molecules. However, constructing biaryl‐bridged macrocycles smaller than 14‐membered ring remains challenging, partially due to the strain present in the cyclic intermediates formed during their synthesis. Here, we report that a Pd catalyst supported by P( t Bu) 3 effectively promotes the intramolecular ortho C─H arylation of phenols with aryl bromides, leading to the efficient synthesis of both strained 2‐hydroxybiaryl‐bridged macrocycles and strain‐free bimolecular counterparts. The success of this Pd‐catalyzed intramolecular cyclization in generating strained macrocycles originates from the dissociation of the P( t Bu) 3 ligand from the Pd center, which facilitates dual chelation of functional groups of substrates to the Pd center of palladacycle intermediate for alleviating its strain. Additionally, Pd catalysts supported by PPh 3 promote intermolecular cyclization of the same substrates, enabling formation of larger macrocycles bridged by two 2‐hydroxybiaryl motifs. These two distinct cyclization modes illustrate how phosphine ligands control the switch of chemoselectivity in Pd‐catalyzed cyclizations.

A bittersweet relationship between the cell cycle, circadian clock, and diurnal fluctuations in taste

Global decline of apex scavengers threatens human health

Vertebrate scavengers play a critical role in ecosystem functioning worldwide. Through the cascading effects of their ecological role, scavengers can also alleviate the burden of zoonotic diseases on people. This importance to human health fuels a growing need to understand how vertebrate scavengers and their ecosystem services are faring globally in the Anthropocene. We reviewed the conservation status of 1,376 vertebrate scavenging species and examined the implications for human health. We uncovered that 36% of these species are threatened or decreasing in population abundance and that apex (large-bodied or obligate) scavengers are disproportionately imperiled. In contrast, mesoscavengers (small-bodied or facultative) are thriving from anthropogenic food subsidies and ecological release. We posit that this global shift in scavenger community structure increases carrion persistence enabling zoonotic pathogens to propagate. Our analysis also indicates that the release of mesoscavengers is associated with reservoir host proliferation, potentially further exacerbating human disease burdens. Urgently tackling the key threats to scavengers—intensive livestock production, land use change, wildlife trade, and the interactions among them—is critical to securing the long-term public health benefits of the world’s diverse scavenger communities.

Caveolin invasion of lipid territory

Humanized mice to model rare human diseases

Optimizing Molecular Packing and Interfacial Contact via Halogenated N‐Glycidyl Carbazole Small Molecules for Low Energy Loss and Highly Efficient Inverted Perovskite Solar Cells

Abstract Nonideal interfacial contact and non‐radiative voltage loss in self‐assembled monolayers (SAMs)‐based inverted perovskite solar cells (PSCs) limit their further development. Herein, two carbazole‐based molecules with different halogen atoms (X‐OCZ, X = Cl or Br) are developed as efficient interfacial regulators. The halogen effect not only finely modulates the molecular packing, crystallinity, and surface contact potential of the MeO‐2PACz analogue via self‐induced intermolecular interactions but also significantly influences the subsequent crystal growth of perovskite, thus resulting in the formation of high‐quality films with enhanced crystallinity, improved energy level alignment, and depressed non‐radiative recombination. Importantly, the Cl‐OCZ‐mediated device exhibits a minimal interfacial carrier transport energy barrier of 0.10 eV and an impressive charge collection efficiency of 93.6%. Moreover, the target device (aperture area: 0.09 cm 2 ) shows an exceptional efficiency of 26.57% (certified 26.4%) along with enhanced thermal and operational stability. The strategy is also extended to large area devices, delivering efficiencies of 25.0% for a 1 cm 2 device and 22.9% for a 12.96 cm 2 minimodule. This study highlights the halogen role of interfacial small molecules in optimizing molecular packing and interfacial contact toward highly efficient PSCs with minimized energy loss and non‐radiative recombination.

Abrupt shift of El Niño periodicity under CO ₂ mitigation

Removing CO 2 from the atmosphere is emerging as a viable strategy to mitigate global warming, yet the responses of the climate system to CO 2 reduction remain uncertain. One of the most uncertain aspects of El Niño behavior is the change in periodicity in response to CO 2 forcing [O. Alizadeh, Earth-Sci. Rev. 235 , 104246 (2022)]. In this study, we show that climate models consistently project an abrupt shortening of El Niño periodicity once CO 2 reductions commence in ramp-up and ramp-down CO 2 experiments. Besides the contribution of slow mean state changes, this phenomenon is shown to be driven by a southward shift of the Intertropical Convergence Zone (ITCZ) [J.-S. Kug, et al. , Nat. Clim. Chang. 12 , 47–53 (2022)] and the consequent narrowing of El Niño’s spatial pattern, which enhances the effectiveness of ocean heat recharge/discharge processes, thereby shortening its periodicity. This suggests that the abrupt shift in El Niño periodicity results from a cascading reaction involving ITCZ dynamics and El Niño’s spatial configuration. These findings highlight the critical role of the global energy balance in shaping El Niño characteristics.

Human influence on climate detectable in the late 19th century

The physics of the heat-trapping properties of CO 2 were established in the mid-19th century, as fossil fuel burning rapidly increased atmospheric CO 2 levels. To date, however, research has not probed when climate change could have been detected if scientists in the 19th century had the current models and observing network. We consider this question in a thought experiment with state-of-the-art climate models. We assume that the capability to make accurate measurements of atmospheric temperature changes existed in 1860, and then apply a standard “fingerprint” method to determine the time at which a human-caused climate change signal was first detectable. Pronounced cooling of the mid- to upper stratosphere, mainly driven by anthropogenic increases in carbon dioxide, would have been identifiable with high confidence by approximately 1885, before the advent of gas-powered cars. These results arise from the favorable signal-to-noise characteristics of the mid- to upper stratosphere, where the signal of human-caused cooling is large and the pattern of this cooling differs markedly from patterns of intrinsic variability. Even if our monitoring capability in 1860 had not been global, and high-quality stratospheric temperature measurements existed for Northern Hemisphere mid-latitudes only, it still would have been feasible to detect human-caused stratospheric cooling by 1894, only 34 y after the assumed start of climate monitoring. Our study provides strong evidence that a discernible human influence on atmospheric temperature has likely existed for over 130 y.

Increased frequency of planetary wave resonance events over the past half-century

We demonstrate a tripling in the frequency of planetary wave resonance events over the past halfcentury, coinciding with the rise in persistent boreal summer weather extremes. This increase aligns with changes in the underlying climate conditions favoring these events, including amplified Arctic warming and land–sea thermal contrast. We also observe increased prevalence of resonant amplification events following the mature phase of strong El Niño events, suggesting that such events may precondition the mean state conditions in ways that favor large-scale quasi-stationary wave patterns and quasi-resonant wave amplification. Since the impact of anthropogenic warming on quasi-resonant amplification is not well captured by current-generation climate models, it is likely that models are underpredicting the potential increase, indicating even greater risk of persistent extreme summer weather events with ongoing warming.

Solvent‐Driven Interconversion of Pyridine Dicarbanion‐Bonded Ag ₁₃ Nanocluster Isomers

Abstract Solvent screening is pivotal for optimizing metal‐catalyzed reactions, yet its impact on the in situ formation and reactivity of polynuclear organometallic clusters remains underexplored. We herein isolate two distinct thirteen‐membered silver cluster isomers, Ag 13 ‐A and Ag 13 ‐M , in acetone and methanol, respectively. Significantly, we demonstrate the interconversion of these isomers facilitated by solvent manipulation. Mechanistic studies on the solvent‐driven Ag 13 ‐A to Ag 13 ‐M transformation reveal this transformation proceeds with a low activation energy (23.39 ± 0.81 kcal mol −1 ) and positive entropy, involving counter anion dissociation, ligand twisting, and re‐coordination. The observed differences in thermal stability and reactivity between two isomers are attributed to variations in Ag–Ag interactions and surface ligand arrangements, underscoring the critical role of solvent selection in affecting the whole organic transformation through in situ formed clusters. These results highlight the necessity of considering organometallic cluster intermediates in solvent screening.

Humans program artificial delegates to accurately solve collective-risk dilemmas but lack precision

In an era increasingly influenced by autonomous machines, it is only a matter of time before strategic individual decisions that impact collective goods will also be made virtually through the use of artificial delegates. Through a series of behavioral experiments that combine delegation to autonomous agents and different choice architectures, we pinpoint what may get lost in translation when humans delegate to algorithms. We focus on the collective-risk dilemma, a game where participants must decide whether or not to contribute to a public good, where the latter must reach a target in order for them to keep their personal endowments. To test the effect of delegation beyond its functionality as a commitment device, participants are asked to play the game a second time, with the same group, where they are given the chance to reprogram their agents. As our main result we find that, when the action space is constrained, people who delegate contribute more to the public good, even if they have experienced more failure and inequality than people who do not delegate. However, they are not more successful. Failing to reach the target, after getting close to it, can be attributed to precision errors in the agent’s algorithm that cannot be corrected amid the game. Thus, with the digitization and subsequent limitation of our interactions, artificial delegates appear to be a solution to help preserving public goods over many iterations of risky situations. But actual success can only be achieved if humans learn to adjust their agents’ algorithms.

Monocytes use protrusive forces to generate migration paths in viscoelastic collagen-based extracellular matrices

Circulating monocytes are recruited to the tumor microenvironment, where they can differentiate into macrophages that mediate tumor progression. To reach the tumor microenvironment, monocytes must first extravasate and migrate through the type-1 collagen rich stromal matrix. The viscoelastic stromal matrix around tumors not only stiffens relative to normal stromal matrix, but often exhibits enhanced viscous characteristics, as indicated by a higher loss tangent or faster stress relaxation rate. Here, we studied how changes in matrix stiffness and viscoelasticity impact the three-dimensional (3D) migration of monocytes through stromal-like matrices. Interpenetrating networks of type-1 collagen and alginate, which enable independent tunability of stiffness and stress relaxation over physiologically relevant ranges, were used as confining matrices for 3D culture of monocytes. Increased stiffness and faster stress relaxation independently enhanced the 3D migration of monocytes. Migrating monocytes have an ellipsoidal or rounded wedge-like morphology, reminiscent of amoeboid migration, with accumulation of actin at the trailing edge. Matrix adhesions were dispensable for monocyte migration in 3D, but migration did require actin polymerization and myosin contractility. Mechanistic studies indicate that actin polymerization at the leading edge generates protrusive forces that open a path for the monocytes to migrate through in the confining viscoelastic matrices. Taken together, our findings implicate matrix stiffness and stress relaxation as key mediators of monocyte migration and reveal how monocytes use pushing forces at the leading edge mediated by actin polymerization to generate migration paths in confining viscoelastic matrices.

Synergistic Mechanism for Unconventional Anodic Reaction of Aldehyde Oxidation for Hydrogen Production

Abstract Anodic reactions involving non‐faradaic processes have significantly expanded the potential application of anodic oxidation half‐reactions. Metallic Cu materials can catalyze an unconventional anodic aldehyde oxidation reaction involving the non‐faradaic H 2 production (AOR‐H 2 ). AOR‐H 2 has distinct advantages of ultra‐low thermodynamic potentials and high value‐added redox products, etc., but the question of exactly how reduction steps occur during AOR‐H 2 , is something which has long puzzled scientists. Here we illustrate the novel synergistic mechanism of nonelectrochemical/electrochemical redox steps in AOR‐H 2 . Aldehyde undergoes hydration, deprotonation, and spontaneous C–H homolytic cleavage to generate H 2 , and then is electrochemically oxidized to form carboxylate. Decorating Cu catalysts with metallic Pt species, supported by theoretical calculations, leads to a 12‐fold increase in the intrinsic activity of AOR‐H 2 . This work inspires researchers to develop novel cathodic and anodic reactions involving the non‐faradaic process for breaking through the limit of existing energy conversion systems.

Siderite and ferric oxyhydroxides imply interlinked carbon, iron, and halogen cycles on Mars

Pure siderite [Fe II CO 3 ] was recently discovered in abundant quantities (4.8 to 10.5 wt.%) by the Curiosity rover at Gale crater, Mars. Diagenetic alteration of siderite likely caused the carbonate-sequestered CO 2 to be released back into the atmosphere and consequently produced ferric [Fe(III)] oxyhydr(oxide) minerals. Here, using laboratory experimentation, we demonstrate that while closed system acid diagenesis—as proposed for Gale crater—is incapable of effective siderite alteration in Mars-relevant fluids, oxyhalogen compounds (chlorate and bromate) can weather siderite not only at acidic pH but also in near-neutral Mars-relevant solutions. The ferric oxyhydroxide minerals produced as a consequence are controlled by the diagenetic fluid composition. While photooxidation is possible, the mutually exclusive products of alteration—magnetite (Fe 3 O 4 ) during ultraviolet irradiation and ferric oxyhydroxide (FeOOH) by oxyhalogens—demonstrate that siderite at Gale crater underwent chemical weathering by chlorate and bromate brines owing to the complete absence of magnetite in drill samples containing siderite. We propose a top–down oxyhalogen brine percolation model to explain the iron mineralogy of the sulfate-rich unit at Gale crater. We conclude that siderite alteration by acidic fluids alone cannot explain the redox disequilibrium witnessed in Gale crater sediments as promulgated before and siderite weathering by oxyhalogen brines is the most likely explanation. It is highly likely that the halogen cycle on Mars is interlinked to the iron and the carbon cycle on early and current Mars.

Collective cooperative intelligence

Cooperation at scale is critical for achieving a sustainable future for humanity. However, achieving collective, cooperative behavior—in which intelligent actors in complex environments jointly improve their well-being—remains poorly understood. Complex systems science (CSS) provides a rich understanding of collective phenomena, the evolution of cooperation, and the institutions that can sustain both. Yet, much of the theory in this area fails to fully consider individual-level complexity and environmental context—largely for the sake of tractability and because it has not been clear how to do so rigorously. These elements are well captured in multiagent reinforcement learning (MARL), which has recently put focus on cooperative (artificial) intelligence. However, typical MARL simulations can be computationally expensive and challenging to interpret. In this perspective, we propose that bridging CSS and MARL affords new directions forward. Both fields can complement each other in their goals, methods, and scope. MARL offers CSS concrete ways to formalize cognitive processes in dynamic environments. CSS offers MARL improved qualitative insight into emergent collective phenomena. We see this approach as providing the necessary foundations for a proper science of collective, cooperative intelligence. We highlight work that is already heading in this direction and discuss concrete steps for future research.

Synergistic C─N Coupling for Efficient Cyclohexanone Oxime Synthesis from Ambient Air by Supported Molecular Catalysts

Abstract Electrocatalytic synthesis of cyclohexanone oxime from rich nitrogen resources is a promising alternative to traditional industrial processes. However, the difficulties in unraveling atomic‐scale catalytic mechanisms and managing selective C─N coupling still pose great challenges to realizing considerable yield and selectivity, and therefore rational catalyst design to boost collaborative C─N coupling for oxime synthesis is particularly attractive. In the present work, molecular catalysts are demonstrated to be unique for oxime synthesis under mild conditions, i.e., iron bis(pyridyl)amine‐bipyridine (FeBPAbipyH) modified MWCNTs@CP (multi‐walled carbon nanotubes coated carbon fiber paper) cathodes produced cyclohexanone oxime from NO 2 − and cyclohexanone, attaining mass‐specific efficiency of 87.00 mg h −1  cm −2  mg cat −1 , Faradaic efficiency (FE) of 77.3%, and exclusive carbon selectivity, which is the best efficiency known to date in H‐cell. Mechanistic studies showed that the FeBPAbipyH molecular skeleton exhibited intimate interaction with both cyclohexanone and NO 2 − , and catalyzed selective NO 2 − ‐to‐NH 2 OH reduction for C─N bond in situ. The in‐depth understanding of substrate‐catalyst interactions and synergic C─N coupling from molecular points of view offers valuable insights to boost collaborative synthesis of organic nitrogen compounds. Further integrating plasma‐driven N 2 oxidation and electrocatalysis enabled cyclohexanone oxime formation at 61.73 mg h −1  cm −2  mg cat −1 on the FeBPAbipyH/MWCNTs@CP electrode, and the whole synthetic and separation process is projected to be profitable with a promising cost of $2709 ton −1 , which is much lower than the breakeven point (∼$10 000 ton −1 ), representing a sustainable pathway to nitrogenous chemical synthesis from abundant resources under ambient conditions.