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1101. Daily briefing: What we know about autism and why it's on the rise.

作者: Flora Graham.
来源: Nature. 2025年

1102. Author Correction: Endophilin marks and controls a clathrin-independent endocytic pathway.

作者: Emmanuel Boucrot.;Antonio P A Ferreira.;Leonardo Almeida-Souza.;Sylvain Debard.;Yvonne Vallis.;Gillian Howard.;Laetitia Bertot.;Nathalie Sauvonnet.;Harvey T McMahon.
来源: Nature. 2025年645卷8081期E7页

1103. Dissecting causal relationships between cortical morphology and neuropsychiatric disorders: a bidirectional Mendelian randomization study.

作者: Bochao Danae Lin.;Yunzhi Li.;Anastasia A Goula.;Xiao Chang.;Katrina L Grasby.;Sarah Medland.;Ole A Andreassen.;Bart P F Rutten.;Sinan Guloksuz.;Dennis van der Meer.;Jurjen J Luykx.
来源: Nat Ment Health. 2025年3卷6期613-625页
Brain cortical morphology, indexed by its surface area and thickness, is known to be highly heritable. Previous research has suggested a relationship of cortical morphology with several neuropsychiatric phenotypes. However, the multitude of potential confounders makes it difficult to establish causal relationships. Here, we employ Generalized Summary-data-based Mendelian Randomization and a series of sensitivity analyses to investigate causal links between 70 cortical morphology measures and 199 neuropsychiatric, behavioral, and metabolic phenotypes. We show that total brain cortical surface area (TSA) has significant positive causal effects on 18 phenotypes. The strongest effects include TSA positively influencing cognitive performance, while reverse analyses reveal small effects of cognitive performance on TSA. Global mean cortical thickness (MTH) exhibits significant causal effects on five phenotypes, including schizophrenia. MTH reduces schizophrenia risk and bidirectional causality is found between MTH and smoking initiation. Finally, in regional analyses we detect positive influences of the transverse temporal surface area on cognitive performance and negative influences of transverse temporal thickness on schizophrenia risk. Overall, our results highlight bidirectional associations between TSA, MTH, and neuropsychiatric traits. These insights offer potential avenues for intervention studies aimed at improving brain health.

1104. Retraction Note: Crystal structures of agonist-bound human cannabinoid receptor CB1.

作者: Tian Hua.;Kiran Vemuri.;Spyros P Nikas.;Robert B Laprairie.;Yiran Wu.;Lu Qu.;Mengchen Pu.;Anisha Korde.;Shan Jiang.;Jo-Hao Ho.;Gye Won Han.;Kang Ding.;Xuanxuan Li.;Haiguang Liu.;Michael A Hanson.;Suwen Zhao.;Laura M Bohn.;Alexandros Makriyannis.;Raymond C Stevens.;Zhi-Jie Liu.
来源: Nature. 2025年645卷8080期544页

1105. Cocaine chemogenetics blunts drug-seeking by synthetic physiology.

作者: Juan L Gomez.;Christopher J Magnus.;Jordi Bonaventura.;Oscar Solis.;Fallon P Curry.;Marjorie R Levinstein.;Reece C Budinich.;Meghan L Carlton.;Emilya N Ventriglia.;Sherry Lam.;Le Wang.;Ingrid Schoenborn.;William Dunne.;Michael Michaelides.;Scott M Sternson.
来源: Nature. 2025年646卷8085期746-753页
Chemical feedback is ubiquitous in physiology but is challenging to study without perturbing basal functions. One example is addictive drugs, which elicit a positive-feedback cycle of drug-seeking and ingestion by acting on the brain to increase dopamine signalling1-3. However, interfering with this process by altering basal dopamine also adversely affects learning, movement, attention and wakefulness4. Here, inspired by physiological control systems, we developed a highly selective synthetic physiology approach to interfere with the positive-feedback cycle of addiction by installing a cocaine-dependent opposing signalling process into this body-brain signalling loop. We used protein engineering to create cocaine-gated ion channels that are selective for cocaine over other drugs and endogenous molecules. Expression of an excitatory cocaine-gated channel in the rat lateral habenula, a brain region that is normally inhibited by cocaine, suppressed cocaine self-administration without affecting food motivation. This artificial cocaine-activated chemogenetic process reduced the cocaine-induced extracellular dopamine rise in the nucleus accumbens. Our results show that cocaine chemogenetics is a selective approach for countering drug reinforcement by clamping dopamine release in the presence of cocaine. In the future, chemogenetic receptors could be developed for additional addictive drugs or hormones and metabolites, which would facilitate efforts to probe their neural circuit mechanisms using a synthetic physiology approach. As these chemogenetic ion channels are specific for cocaine over natural rewards, they may also offer a route towards gene therapies for cocaine addiction.

1106. A compressed hierarchy for visual form processing in the tree shrew.

作者: Frank F Lanfranchi.;Joseph Wekselblatt.;Daniel A Wagenaar.;Doris Y Tsao.
来源: Nature. 2025年646卷8086期872-882页
Our knowledge of the brain processes that govern vision is largely derived from studying primates, whose hierarchically organized visual system1 inspired the architecture of deep neural networks2. This raises questions about the universality of such hierarchical structures. Here we examined the large-scale functional organization for vision in one of the closest living relatives to primates, the tree shrew. We performed Neuropixels recordings3,4 across many cortical and thalamic areas spanning the tree shrew ventral visual system while presenting a large battery of visual stimuli in awake tree shrews. We found that receptive field size, response latency and selectivity for naturalistic textures, compared with spectrally matched noise5, all increased moving anteriorly along the tree shrew visual pathway, consistent with a primate-like hierarchical organization6,7. However, tree shrew area V2 already harboured a high-level representation of complex objects. First, V2 encoded a complete representation of a high-level object space8. Second, V2 activity supported the most accurate object decoding and reconstruction among all tree shrew visual areas. In fact, object decoding accuracy from tree shrew V2 was comparable to that in macaque posterior IT and substantially higher than that in macaque V2. Finally, starting in V2, we found strongly face-selective cells resembling those reported in macaque inferotemporal cortex9. Overall, these findings show how core computational principles of visual form processing found in primates are conserved, yet hierarchically compressed, in a small but highly visual mammal.

1107. Rate and noise in human amygdala drive increased exploration in aversive learning.

作者: Tamar Reitich-Stolero.;Kristoffer C Aberg.;Dean Halperin.;Carmel Ariel.;Genela Morris.;Lilach Goldstein.;Firas Fahoum.;Ido Strauss.;Rony Paz.
来源: Nature. 2025年646卷8086期883-892页
To cope in uncertain environments, animals must balance their actions between using current resources and searching for new ones1. This exploration-exploitation dilemma has been studied extensively in paradigms involving positive outcomes, and neural correlates have been identified in frontal cortices and subcortical structures2-11, including the amygdala12. Importantly, exploration is just as essential for survival or well-being when trying to avoid negative outcomes, yet we do not know whether the single-neuron mechanisms that drive exploration are shared across positive and negative environments. Here we examined the dynamics of exploration when human participants engaged in a probabilistic learning task with intermixed loss and gain trials, while simultaneously recording single-neuron activity. We show that neurons of the amygdala and temporal cortex modulate their activity before a decision to explore in both loss and gain. Moreover, we find that humans exhibit more exploration when trying to avoid losses, and that an increase in the levels of noise in amygdala neurons contributes to this behaviour. Overall, we report that human exploration is driven by two distinct neural mechanisms, a valence-independent rate signal and a valence-dependent global noise signal. The results suggest a link between the heightened amygdala activity observed in mood disorders13,14 and higher exploration rates15-17 that underlie maladaptive and even pathological behaviours.

1108. Topological prethermal strong zero modes on superconducting processors.

作者: Feitong Jin.;Si Jiang.;Xuhao Zhu.;Zehang Bao.;Fanhao Shen.;Ke Wang.;Zitian Zhu.;Shibo Xu.;Zixuan Song.;Jiachen Chen.;Ziqi Tan.;Yaozu Wu.;Chuanyu Zhang.;Yu Gao.;Ning Wang.;Yiren Zou.;Aosai Zhang.;Tingting Li.;Jiarun Zhong.;Zhengyi Cui.;Yihang Han.;Yiyang He.;Han Wang.;Jia-Nan Yang.;Yanzhe Wang.;Jiayuan Shen.;Gongyu Liu.;Jinfeng Deng.;Hang Dong.;Pengfei Zhang.;Weikang Li.;Dong Yuan.;Zhide Lu.;Zheng-Zhi Sun.;Hekang Li.;Junxiang Zhang.;Chao Song.;Zhen Wang.;Qiujiang Guo.;Francisco Machado.;Jack Kemp.;Thomas Iadecola.;Norman Y Yao.;H Wang.;Dong-Ling Deng.
来源: Nature. 2025年645卷8081期626-632页
Symmetry-protected topological phases1-4 cannot be described by any local order parameter and are beyond the conventional symmetry-breaking model5. They are characterized by topological boundary modes that remain stable under symmetry respecting perturbations1-4,6-8. In clean, gapped systems without disorder, the stability of these edge modes is restricted to the zero-temperature manifold; at finite temperatures, interactions with mobile thermal excitations lead to their decay9-11. Here we report the observation of a distinct type of topological edge mode12-14, which is protected by emergent symmetries and persists across the entire spectrum, in an array of 100 programmable superconducting qubits. Through digital quantum simulation of a one-dimensional disorder-free stabilizer Hamiltonian, we observe robust long-lived topological edge modes over up to 30 cycles for a wide range of initial states. We show that the interaction between these edge modes and bulk excitations can be suppressed by dimerizing the stabilizer strength, leading to an emergent U(1) × U(1) symmetry in the prethermal regime of the system. Furthermore, we exploit these topological edge modes as logical qubits and prepare a logical Bell state, which exhibits persistent coherence, despite the system being disorder-free and at finite temperature. Our results establish a viable digital simulation approach15-18 to experimentally study topological matter at finite temperature and demonstrate a potential route to construct long-lived, robust boundary qubits in disorder-free systems.

1109. Attosecond control and measurement of chiral photoionization dynamics.

作者: Meng Han.;Jia-Bao Ji.;Alexander Blech.;R Esteban Goetz.;Corbin Allison.;Loren Greenman.;Christiane P Koch.;Hans Jakob Wörner.
来源: Nature. 2025年645卷8079期95-100页
Many chirality-sensitive light-matter interactions are governed by chiral electron dynamics. Therefore, the development of advanced technologies making use of chiral phenomena would critically benefit from measuring and controlling chiral electron dynamics on their natural attosecond timescales. Such endeavours have so far been hampered by the lack of characterized circularly polarized attosecond pulses, an obstacle that has recently been overcome1,2. Here we introduce chiroptical spectroscopy with attosecond pulses and demonstrate attosecond coherent control over photoelectron circular dichroism (PECD)3,4, as well as the measurement of chiral asymmetries in the forward-backward and angle-resolved photoionization delays of chiral molecules. We show that co-rotating attosecond and near-infrared (IR) pulses can nearly double the PECD and even change its sign compared with single-photon ionization. We demonstrate that chiral photoionization delays depend on both polar and azimuthal angles of photoemission in the light-propagation frame, requiring 3D momentum resolution. We measure forward-backward chiral-sensitive delays of up to 60 as and polar-angle-resolved photoionization delays of up to 240 as, which include an asymmetry of about 60 as originating from chirality in the continuum-continuum transitions. Attosecond chiroptical spectroscopy opens the door to quantitatively understanding and controlling the dynamics of chiral molecules on the electronic timescale.

1110. The evolution of hominin bipedalism in two steps.

作者: Gayani Senevirathne.;Serena C Fernandopulle.;Daniel Richard.;Stephanie L Baumgart.;Anika Liv Christensen.;Matteo Fabbri.;Jakob Höppner.;Harald Jüppner.;Peishu Li.;Vivien Bothe.;Nadia Fröbisch.;Ian Simcock.;Owen J Arthurs.;Alistair Calder.;Naomi Freilich.;Niamh C Nowlan.;Ian A Glass.;April Craft.;Terence D Capellini.
来源: Nature. 2025年645卷8082期952-963页
Bipedalism is a human-defining trait1-3. It is made possible by the familiar, bowl-shaped pelvis, whose short, wide iliac blades curve along the sides of the body to stabilize walking and support internal organs and a large-brained, broad-shouldered baby4-6. The ilium changes compared with living primates are an evolutionary novelty7. However, how this evolution came about remains unknown. Here, using a multifaceted histological, comparative genomic and functional genomic approach, we identified the developmental bases of the morphogenetic shifts in the human pelvis that made bipedalism possible. First, we observe that the human ilium cartilage growth plate underwent a heterotopic shift, residing perpendicular to the orientation present in other primate (and mouse) ilia. Second, we observe heterochronic and heterotopic shifts in ossification that are unlike those in non-human primate ilia or human long bones. Ossification initiates posteriorly, resides externally with fibroblast (and perichondral) cells contributing to osteoblasts, and is delayed compared with other bones in humans and with primate ilia. Underlying these two shifts are regulatory changes in an integrated chondrocyte-perichondral-osteoblast pathway, involving complex hierarchical interactions between SOX9-ZNF521-PTH1R and RUNX2-FOXP1/2. These innovations facilitated further growth of the human pelvis and the unique formation of the ilium among primates.

1111. Mechanical confinement governs phenotypic plasticity in melanoma.

作者: Miranda V Hunter.;Eshita Joshi.;Sydney Bowker.;Emily Montal.;Yilun Ma.;Young Hun Kim.;Zhifan Yang.;Laura Tuffery.;Zhuoning Li.;Eric Rosiek.;Alexander Browning.;Reuben Moncada.;Itai Yanai.;Helen Byrne.;Mara Monetti.;Elisa de Stanchina.;Pierre-Jacques Hamard.;Richard P Koche.;Richard M White.
来源: Nature. 2025年647卷8089期517-527页
Phenotype switching is a form of cellular plasticity in which cancer cells reversibly move between two opposite extremes: proliferative versus invasive states1,2. Although it has long been hypothesized that such switching is triggered by external cues, the identity of these cues remains unclear. Here we demonstrate that mechanical confinement mediates phenotype switching through chromatin remodelling. Using a zebrafish model of melanoma coupled with human samples, we profiled tumour cells at the interface between the tumour and surrounding microenvironment. Morphological analysis of interface cells showed elliptical nuclei, suggestive of mechanical confinement by the adjacent tissue. Spatial and single-cell transcriptomics demonstrated that interface cells adopted a gene program of neuronal invasion, including the acquisition of an acetylated tubulin cage that protects the nucleus during migration. We identified the DNA-bending protein HMGB2 as a confinement-induced mediator of the neuronal state. HMGB2 is upregulated in confined cells, and quantitative modelling revealed that confinement prolongs the contact time between HMGB2 and chromatin, leading to changes in chromatin configuration that favour the neuronal phenotype. Genetic disruption of HMGB2 showed that it regulates the trade-off between proliferative and invasive states, in which confined HMGB2high tumour cells are less proliferative but more drug-resistant. Our results implicate the mechanical microenvironment as a mechanism that drives phenotype switching in melanoma.

1112. Global phenology maps reveal the drivers and effects of seasonal asynchrony.

作者: Drew E Terasaki Hart.;Thảo-Nguyên Bùi.;Lauren Di Maggio.;Ian J Wang.
来源: Nature. 2025年645卷8079期133-140页
Terrestrial plant communities show great variation in their annual rhythms of growth, or seasonal phenology1,2. The geographical patterns resulting from this variation, known as land surface phenology (LSP)3, contain valuable information for the study of ecosystem function4,5, plant ecophysiology6-8, landscape ecology9,10 and evolutionary biogeography11-13. Yet globally consistent LSP mapping has been hampered by methods that struggle to represent the full range of seasonal phenologies occurring across terrestrial biomes14, especially the subtle and complex phenologies of many arid and tropical ecosystems1,15,16. Here, using a data-driven analysis of satellite imagery to map LSP worldwide, we provide insights into Earth's phenological diversity, documenting both intercontinental convergence between similar climates and regional heterogeneity associated with topoclimate, ecohydrology and vegetation structure. We then map spatial phenological asynchrony and the modes of asynchronous seasonality that control it, identifying hotspots of asynchrony in tropical mountains and Mediterranean climate regions and reporting evidence for the hypothesis that climatically similar sites exhibit greater phenological asynchrony within the tropics. Finally, we find that our global LSP map predicts complex geographical discontinuities in flowering phenology, genetic divergence and even harvest seasonality across a range of taxa, establishing remote sensing as a crucial tool for understanding the ecological and evolutionary consequences of allochrony by allopatry.

1113. Crystal structures of agonist-bound human cannabinoid receptor CB1.

作者: Tian Hua.;Kiran Vemuri.;Spyros P Nikas.;Yiran Wu.;Lu Qu.;Mengchen Pu.;Anisha Korde.;Shan Jiang.;Jo-Hao Ho.;Gye Won Han.;Kang Ding.;Xuanxuan Li.;Haiguang Liu.;Michael A Hanson.;Suwen Zhao.;Laura M Bohn.;Alexandros Makriyannis.;Raymond C Stevens.;Zhi-Jie Liu.
来源: Nature. 2025年646卷8085期754-758页
Cannabinoid receptor 1 (CB1) is the primary target of the partial agonist Δ9-tetrahydrocannabinol (Δ9-THC), the psychoactive constituent of marijuana1. Here we report two agonist-bound crystal structures of human CB1 in complex with a tetrahydrocannabinol (AM11542) and a hexahydrocannabinol (AM841). The two CB1-agonist complexes reveal important conformational changes in the overall structure relative to the antagonist-bound state2, including a 53% reduction in the volume of the ligand-binding pocket and an increase in the surface area of the G protein-binding region. Furthermore, a twin toggle switch of Phe2003.36 and Trp3566.48 (where the superscripts denote Ballesteros-Weinstein numbering3) is experimentally observed and seems to be essential for receptor activation. The structures reveal important insights into the activation mechanism of CB1 and provide a molecular basis for predicting the binding modes of Δ9-THC, and endogenous and synthetic cannabinoids. The plasticity of the binding pocket of CB1 seems to be a common feature among certain class A G protein-coupled receptors. These findings should inspire the design of chemically diverse ligands with distinct pharmacological properties.

1114. One-shot design of functional protein binders with BindCraft.

作者: Martin Pacesa.;Lennart Nickel.;Christian Schellhaas.;Joseph Schmidt.;Ekaterina Pyatova.;Lucas Kissling.;Patrick Barendse.;Jagrity Choudhury.;Srajan Kapoor.;Ana Alcaraz-Serna.;Yehlin Cho.;Kourosh H Ghamary.;Laura Vinué.;Brahm J Yachnin.;Andrew M Wollacott.;Stephen Buckley.;Adrie H Westphal.;Simon Lindhoud.;Sandrine Georgeon.;Casper A Goverde.;Georgios N Hatzopoulos.;Pierre Gönczy.;Yannick D Muller.;Gerald Schwank.;Daan C Swarts.;Alex J Vecchio.;Bernard L Schneider.;Sergey Ovchinnikov.;Bruno E Correia.
来源: Nature. 2025年646卷8084期483-492页
Protein-protein interactions are at the core of all key biological processes. However, the complexity of the structural features that determine protein-protein interactions makes their design challenging. Here we present BindCraft, an open-source and automated pipeline for de novo protein binder design with experimental success rates of 10-100%. BindCraft leverages the weights of AlphaFold2 (ref. 1) to generate binders with nanomolar affinity without the need for high-throughput screening or experimental optimization, even in the absence of known binding sites. We successfully designed binders against a diverse set of challenging targets, including cell-surface receptors, common allergens, de novo designed proteins and multi-domain nucleases, such as CRISPR-Cas9. We showcase the functional and therapeutic potential of designed binders by reducing IgE binding to birch allergen in patient-derived samples, modulating Cas9 gene editing activity and reducing the cytotoxicity of a foodborne bacterial enterotoxin. Last, we use cell-surface-receptor-specific binders to redirect adeno-associated virus capsids for targeted gene delivery. This work represents a significant advancement towards a 'one design-one binder' approach in computational design, with immense potential in therapeutics, diagnostics and biotechnology.

1115. Dual-scale chemical ordering for cryogenic properties in CoNiV-based alloys.

作者: Tiwen Lu.;Binhan Sun.;Yue Li.;Sheng Dai.;Ning Yao.;Wenbo Li.;Xizhen Dong.;Xiyu Chen.;Jiacheng Niu.;Fan Ye.;Alisson Kwiatkowski da Silva.;Shuya Zhu.;Yu Xie.;Xiaofeng Yang.;Sihao Deng.;Jianping Tan.;Zhiming Li.;Dirk Ponge.;Lunhua He.;Xian-Cheng Zhang.;Dierk Raabe.;Shan-Tung Tu.
来源: Nature. 2025年645卷8080期385-391页
The mechanical properties of metallic materials often degrade under harsh cryogenic conditions, posing challenges for low-temperature infrastructures1. Here we introduce a dual-scale atomic-ordering nanostructure, characterized by an exceptionally high number density of co-existing subnanoscale short-range ordering (approximately 2.4 × 1026 m-3) and nanoscale long-range ordering (approximately 4.5 × 1025 m-3) domains, within a metallic solid-solution matrix in a CoNiV-based alloy to improve the synergy of strength and ductility at low temperatures. We observe an ordering-induced increase in dislocation shear stress as well as a more rapid dislocation multiplication owing to the dislocation blocking effect of nanoscale long-range ordering and the associated generation of new dislocations. The latter effect also releases stress concentrations at nanoscale long-range-ordered obstacles that otherwise would promote damage initiation and failure. Consequently, the alloy shows a strength-elongation product of 76 GPa % with a yield strength of approximately 1.2 GPa at 87 K, outperforming materials devoid of such ordering hierarchy, containing only short-range ordered or coherent precipitates of a few tens of nanometres. Our results highlight the impact of dual co-existing chemical ordering on the mechanical properties of complex alloys and offer guidelines to control these ordering states to enhance their mechanical performance for cryogenic applications.

1116. Electrically driven lasing from a dual-cavity perovskite device.

作者: Chen Zou.;Zhixiang Ren.;Kangshuo Hui.;Zixiang Wang.;Yangning Fan.;Yichen Yang.;Bo Yuan.;Baodan Zhao.;Dawei Di.
来源: Nature. 2025年645卷8080期369-374页
Solution-processed semiconductor lasers promise lightweight, wearable and scalable optoelectronic applications. Among the gain media for solution-processed lasers, metal halide perovskites stand out as an exceptional class because of their ability to achieve wavelength-adjustable, low-threshold lasing under optical pumping1-8. Despite the progress in this field, electrically driven lasing from perovskite semiconductors remains a critical challenge. Here we demonstrate an electrically driven perovskite laser, constructed by vertically integrating a low-threshold single-crystal perovskite microcavity sub-unit with a high-power microcavity perovskite LED (PeLED) sub-unit. Under pulsed electrical excitation, the dual-cavity perovskite device shows a minimum lasing threshold of 92 A cm-2 (average threshold: 129 A cm-2, at about 22 °C, in air), which is an order of magnitude lower than that of state-of-the-art electrically driven organic lasers9,10. Key to this demonstration is the integrated dual-cavity device architecture, which allows the microcavity PeLED sub-unit to deliver directional emission into the single-crystal perovskite microcavity sub-unit (at a coupling efficiency of about 82.7%) to establish the lasing action. An operational half-life (T50) of 1.8 h (6.4 × 104 voltage pulses at 10 Hz) is achieved, outperforming the stability of electrically pumped organic lasers9,10. The dual-cavity perovskite laser can be rapidly modulated at a bandwidth of 36.2 MHz, indicating its potential for data transmission and computational applications.

1117. Haematopoietic stem cell number is not solely defined by niche availability.

作者: Shoichiro Takeishi.;Tony Marchand.;Wade R Koba.;Daniel K Borger.;Chunliang Xu.;Chandan Guha.;Aviv Bergman.;Paul S Frenette.;Kira Gritsman.;Ulrich Steidl.
来源: Nature. 2025年646卷8085期687-696页
Haematopoietic stem cells (HSCs) reside in specialized microenvironments, referred to as niches, and the classical model suggests that HSC numbers are predominantly determined by the niche size1-5. However, the vast excess of niche cells relative to HSCs challenges this perspective. To rigorously define the role of niche size in regulating HSC numbers, we developed a femur-transplantation system, enabling us to increase available HSC niches. Notably, the addition of niches did not alter the total HSC numbers in the body, suggesting the presence of a systemic mechanism that limits HSC numbers. Additionally, HSC numbers in transplanted wild-type femurs did not exceed physiological levels when HSCs were mobilized from defective endogenous niches to the periphery, indicating that HSC numbers are constrained at the local level as well. The notion of dual restrictions at systemic and local levels was further supported by other experimental approaches, including parabiosis and non-conditioned transfer of HSCs after bone transplantation. Moreover, we found that thrombopoietin has a pivotal role in determining the total number of HSCs in the body, even in the context of increased niche availability. Our study redefines key principles underlying HSC number regulation, providing insights into this critical biological process.

1118. Extreme armour in the world's oldest ankylosaur.

作者: Susannah C R Maidment.;Driss Ouarhache.;Kawtar Ech-Charay.;Ahmed Oussou.;Khadija Boumir.;Abdessalam El Khanchoufi.;Alison Park.;Luke E Meade.;D Cary Woodruff.;Simon Wills.;Mike Smith.;Paul M Barrett.;Richard J Butler.
来源: Nature. 2025年647卷8088期121-126页
The armoured ankylosaurian dinosaurs are best known from Late Cretaceous Northern Hemisphere ecosystems, but their early evolution in the Early-Middle Jurassic is shrouded in mystery due to a poor fossil record1,2. Spicomellus afer was suggested to be the world's oldest ankylosaur and the first from Africa, but was based on only a single partial rib from the Middle Jurassic of Morocco3. Here we describe a new, much more complete specimen that confirms the ankylosaurian affinities of Spicomellus, and demonstrates that it has uniquely elaborate dermal armour unlike that of any other vertebrate, extant or extinct. The presence of 'handle' vertebrae in the tail of Spicomellus indicates that it possessed a tail weapon, overturning current understanding of tail club evolution in ankylosaurs, as these structures were previously thought to have evolved only in the Early Cretaceous4. This ornate armour may have functioned for display as well as defence, and a later reduction to simpler armour with less extravagant osteoderms in Late Cretaceous taxa might indicate a shift towards a primarily defensive function, perhaps in response to increased predation pressures or a switch to combative courtship displays.

1119. Epidemiology models explain rumour spreading during France's Great Fear of 1789.

作者: Stefano Zapperi.;Constant Varlet-Bertrand.;Cécile Bastidon.;Caterina A M La Porta.;Antoine Parent.
来源: Nature. 2025年646卷8084期358-364页
The Great Fear of 1789, a wave of panic and unrest in rural France fuelled by the spreading of rumours, was an important moment at the onset of the French Revolution, marking the collapse of feudalism and the rise of the new regime1. The Great Fear provides a vivid example of the role the spreading of rumours has in driving political changes that might be relevant today2,3. Here, we collect existing historical records related to the Great Fear and use epidemiology tools and models4 to reconstruct the network of its transmission from town to town. In this way, we quantify the spatiotemporal spread of the rumours and compute key epidemiological parameters, such as the basic reproduction number. Exploiting information on the structure of the road network in eighteenth century France5, we estimate the most probable diffusion paths of the Great Fear and quantify the distribution of spreading velocities. By endowing the nodes in our reconstructed network with indicators related to the institutional, demographic and socio-economic conditions of the time6, including literacy, population size, political participation, wheat prices7,8, income and ownership laws9, and the unequal distribution of land ownership, we compute factors associated with spread of the Great Fear. Our analysis sheds light on unresolved historiographic issues on the significance of the Great Fear for the French Revolution, providing a quantitative answer to the unresolved debate between the role of emotions and rationality in explaining its diffusion.

1120. How did life get multicellular? Five simple organisms could have the answer.

作者: Alla Katsnelson.
来源: Nature. 2025年644卷8078期856-859页
共有 139596 条符合本次的查询结果, 用时 1.9088356 秒