前沿速递 | ncs 集萃：2026-08-13 期
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1. 宇宙黎明时期被气体包裹且因气体而发红的黑洞
A gas-enshrouded and gas-reddened black hole at cosmic dawn
『Abstract』The physical processes that led to the formation of billion-solar-mass black holes within the first 700 million years of cosmic time, a period known as cosmic dawn, remain a puzzle. Several theoretical scenarios have been proposed to seed and rapidly grow black holes, but direct observations of these mechanisms remain elusive. Here we present a source 660 million years after the Big Bang that exhibits singular properties: among the largest hydrogen Balmer breaks reported at any redshift, broad multi-peaked Hβ emission, and Balmer line absorption in several transitions. We model this source as an enshrouded black hole in which the Balmer break and absorption features are a result of extremely dense, turbulent gas forming a dust-free envelope around a supermassive black hole. This source may provide evidence of an early black hole embedded in dense gas-a theoretical configuration proposed to rapidly grow black holes by super-Eddington accretion. Radiation from the black hole seems to dominate almost all observed light, leaving limited room for contribution from its host galaxy. If the source merged with its brighter neighbour, it would resemble the recently discovered 'little red dots' with perplexing spectral energy distributions. The redness of the black hole is due to gas, not dust, and scattering, not kinematics, gives rise to the complex line shapes and luminosities-black hole masses of these sources may therefore be overestimated by orders of magnitude.
『摘要』
在宇宙时间的前7亿年（即宇宙黎明时期）内形成数十亿太阳质量的黑洞，其物理过程至今仍是一个谜。人们提出了多种理论情景来解释黑洞的种子形成和快速生长，但这些机制尚未得到直接观测证实。本研究展示了一个在大爆炸后6.6亿年的天体，它具有独特性质：在所有红移中氢巴尔末跃变最大、宽多峰Hβ发射以及多个跃迁中的巴尔末线吸收。我们将其建模为一个被包裹的黑洞，其中巴尔末跃变和吸收特征是由围绕超大质量黑洞形成的无尘包层中极端致密且湍动的气体所致。该天体可能为早期嵌入致密气体的黑洞提供了证据——这种理论配置可通过超爱丁顿吸积实现黑洞的快速增长。黑洞辐射几乎主导了所有观测到的光，宿主星系的贡献微乎其微。若该天体与其更亮的邻居合并，则与近期发现的具有复杂光谱能量分布的“小红点”类似。黑洞呈现红色源于气体而非尘埃，而散射而非动力学效应导致了复杂的谱线形状和光度——因此这类天体的黑洞质量可能被高估数个数量级。
『总结』
研究揭示大爆炸后6.6亿年的特殊天体，或为早期黑洞通过超爱丁顿吸积快速生长提供证据，并指出传统方法可能严重高估此类天体的黑洞质量。
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2. 外部螺旋星云中的众多弓形激波
Numerous bow shocks in the outer Helix Nebula
『Abstract』Near the end of their lives, low-mass and intermediate-mass stars expel metal-enriched material in winds and outflows, ultimately producing planetary nebulae. The ejected material is expected to fragment and mix into the interstellar medium (ISM), but this final assimilation step has been difficult to observe directly. Here we report evidence for this process in the form of 22 bow shocks in the eastern outskirts of the Helix Nebula, detected in Hα emission with the partially completed MOTHRA telescope. Unlike the large-scale wind-ISM bow shocks commonly observed around evolved stars, the shocks are compact and associated with individual clumps of gas. Going outward from the central star, the radius of curvature Rc decreases by a factor of roughly 102 over the radial range r = 0.4-1.4 pc. This is accompanied by a morphological transition from thin, well-defined bows to fuzzy, patchy structures. We interpret these changes as progressive stripping and fragmentation of asymptotic giant branch-shell remnants as they interact with the ISM. The slope of the observed Rc-r relation implies a loss of fragment coherence on a timescale of roughly 104 years, providing a rare direct constraint on the timescale for disruption and entrainment of fragmented stellar ejecta into the ISM.
『摘要』
在生命末期，低质量和中质量恒星通过星风和物质外流排出富含金属的物质，最终形成行星状星云。被抛射出的物质预计会碎裂并融入星际介质（ISM），但这一最终的同化过程很难直接观测到。本研究报告了在螺旋星云东郊发现的22个弓形激波的证据，这些激波是通过部分建成的MOTHRA望远镜在Hα发射中探测到的。与通常在演化恒星周围观察到的大尺度星风-星际介质弓形激波不同，这些激波较为紧凑且与单个气体团块相关联。从中心恒星向外延伸，在径向范围r = 0.4–1.4秒差距内，曲率半径Rc减小了约102倍。同时，形态也从薄而清晰的弓形转变为模糊、斑驳的结构。我们将这些变化解释为渐近巨星分支壳层残余物在与星际介质相互作用时发生的渐进剥离和碎裂。观察到的Rc-r关系的斜率表明，碎片的连贯性会在大约104年的时间尺度上丧失，这为破碎恒星喷出物进入星际介质的破坏和夹带时间尺度提供了罕见的直接限制。
『总结』
研究在螺旋星云东郊发现22个弓形激波，揭示低质量和中等质量恒星生命末期排出的物质在与星际介质作用时会发生渐进剥离和碎裂，其碎片连贯性约在104年丧失，为相关时间尺度提供直接限制。
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3. 生态进化反馈重塑了果蝇系统中的竞争动态。
Eco-evolutionary feedback reshapes competitive dynamics in an orchard fly system.
『Abstract』The feedback between competition and evolution is central to hypotheses about the origin and maintenance of species diversity. Yet, whether competition-induced evolution is sufficiently rapid, consistent, and strong to maintain diversity on ecological timescales remains unresolved. We conducted an outdoor mesocosm experiment with four pairs of orchard fly species in which we manipulated species' ability to evolve to one another during interspecific competition. We found significant competition-induced rapid evolution across phenotypes, which typically shifted in parallel across species. This evolution strongly affected the competitive population dynamics of all species pairs, typically boosting the rarer species' abundance, and in one pair, reversing the abundance hierarchy. These results suggest that feedback between competition and evolution may be common and maintain species diversity on ecological timescales.
『摘要』
竞争与进化之间的反馈作用是物种多样性起源与维持假说的核心。然而，竞争引发的进化是否足够迅速、持续且强大，从而在生态时间尺度上维持物种多样性，这一问题仍未得到解决。我们开展了一项户外中宇宙实验，研究对象为四对果蝇物种，实验中我们在种间竞争过程中操控了各物种的相互进化能力。研究发现，表型层面存在显著的由竞争引发的快速进化现象，不同物种的表型变化通常呈平行趋势。这种进化对所有物种对的竞争种群动态产生了显著影响，通常会提高稀有物种的数量，在一组物种对中甚至逆转了数量等级顺序。这些结果表明，竞争与进化之间的反馈可能普遍存在，并在生态时间尺度上维持着物种多样性。
『总结』
通过户外中宇宙实验发现竞争可引发果蝇表型的快速平行进化，该进化能改变物种竞争动态并维持生态时间尺度的物种多样性。
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4. 抗肌萎缩蛋白聚糖的木糖磷酸酶活性对其受体功能进行自我调节。
Xylose phosphatase activity of dystroglycan self-regulates its receptor function.
『Abstract』Dystroglycan (DG) is an extracellular matrix receptor crucial for tissue development and pathogen entry. DG harbors a long, complex glycan called matriglycan. Loss of matriglycan or reduction in its length disrupts DG function, causing dystroglycanopathies. However, the mechanism regulating matriglycan length is unknown. In this study, we found that a xylose kinase facilitated the initiation of matriglycan synthesis by adding a phosphate to the xylose of the matriglycan primer. Matriglycan elongation occurred when the phosphate was removed by the N-terminal domain of DG (DGN). DGN has the conserved DXDXT/V active site motif found in haloacid dehalogenase domains of phosphohydrolases. Mutations in this site abolished DGN phosphatase activity, reduced matriglycan length, and caused muscle disease in mice. Thus, DG has an unexpected xylose phosphatase function involved in regulating matriglycan extension.
『摘要』
抗肌萎缩蛋白聚糖（Dystroglycan，DG）是一种细胞外基质受体，对组织发育和病原体入侵至关重要。DG携带一种名为基质聚糖的复杂长链多糖。基质聚糖缺失或长度缩短会破坏DG功能，导致抗肌萎缩蛋白聚糖病。然而，调控基质聚糖长度的机制尚不清楚。本研究发现，木糖激酶通过向基质聚糖引物的木糖上添加磷酸基团来促进基质聚糖合成的起始。当N端结构域（DGN）去除该磷酸基团时，基质聚糖发生延伸。DGN具有保守的DXDXT/V活性位点基序，存在于磷酸水解酶的卤酸脱卤酶结构域中。该位点的突变使DGN磷酸酶活性丧失、基质聚糖长度缩短，并在小鼠中引发肌肉疾病。因此，DG具有意想不到的木糖磷酸酶功能，参与调控基质聚糖的延伸。
『总结』
研究发现DG具有木糖磷酸酶功能，其N端结构域通过去磷酸化调控基质聚糖延伸，相关位点突变会导致肌肉疾病。
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5. 人工冬眠揭示了与记忆保持相关的突触记忆痕迹结构。
Artificial hibernation reveals synaptic engram architecture associated with memory retention.
『Abstract』Memories leave lasting physical changes at the synaptic level. Although stable, larger spines are thought to support memory, the high turnover of dendritic spines and the drifting of neuronal representations after memory formation suggest alternative possibilities. To elucidate the structural trace underlying memory retention, we used a mouse model of artificial hibernation. During hibernation, hippocampal neurons exhibited a substantial reduction in their activity and an extensive elimination of dendritic spines and synapses. Despite these changes, their memory and associated hippocampal neuronal representations remained intact. We found that a subset of spines characterized by synaptic contacts with multisynaptic boutons is maintained during hibernation. These findings suggest that synaptic engram architecture, rather than larger spines per se, is resilient to network remodeling and associated with long-term memory retention.
『摘要』
记忆会在突触层面留下持久的生理变化。尽管人们认为稳定且较大的树突棘能够支持记忆，但树突棘的高周转率以及记忆形成后神经元表征的漂移表明还存在其他可能性。为了阐明维持记忆的结构痕迹，我们使用了人工冬眠小鼠模型。在冬眠期间，海马体神经元的活动显著减少，树突棘和突触大量消除。尽管发生了这些变化，它们的记忆及相关海马体神经元表征依然完好无损。我们发现，在冬眠过程中，与多突触纽扣有突触接触的一类树突棘得以保留。这些发现表明，突触印记结构而非较大树突棘本身，对网络重塑具有抗性并与长期记忆保持相关联。
『总结』
研究利用人工冬眠小鼠模型发现，记忆相关的海马体神经元活动及树突棘虽在冬眠时大幅减少，但特定与多突触纽扣接触的树突棘被保留，表明突触印记结构而非大体积树突棘是长期记忆保持的关键。
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6. 真核生物染色体，一种通过体积相变实现相互转化的双态系统。
The eukaryote chromosome, a two-state system with interconversion by a volume phase transition.
『Abstract』The formation of metaphase chromosomes requires the activity of condensins, DNA translocases that reduce chromosomal length through the process of loop extrusion. Reduction of length, however, does not account for the increase in density of chromatin in condensed states. Here, we show that eukaryotic chromosomes are ionic hydrogels and that the chromosomal material is a two-state system, with interconversion between condensed and decondensed states through a volume phase transition, analogous to a liquid-gas transition. Ionic contacts between histone tails and DNA, formed and broken by histone acetylation and deacetylation, may control the transition and be responsible for condensation in heterochromatin and decondensation in euchromatin.
『摘要』
中期染色体的形成需要凝聚蛋白的活性，这种DNA转位酶通过环挤出过程缩短染色体长度。然而，长度的缩短并不能解释染色质在浓缩状态下密度增加的原因。本研究表明真核生物染色体是离子水凝胶，染色体物质是一个两态系统，通过体积相变（类似于液气转变）在浓缩和去浓缩状态之间相互转化。组蛋白尾部与DNA之间的离子接触由组蛋白乙酰化和去乙酰化作用形成和破坏，可能控制这一转变过程，并导致异染色质的浓缩和常染色质的去浓缩。
『总结』
研究表明真核生物染色体为离子水凝胶且是两态系统，通过体积相变在浓缩和去浓缩状态间转化，组蛋白相关作用或控制此转变及染色质不同状态的浓缩情况。
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7. 高血压的跨器官单细胞分析。
A cross-organ single-cell analysis of hypertension.
『Abstract』Hypertension is a leading cause of disease burden and mortality. Here, we present a single-cell analysis of hypertension and end-organ damage across six organs and tissues in angiotensin II-treated mice, Dahl salt-sensitive rats, and spontaneously hypertensive rats. We identified gene programs associated with blood pressure and renal injury, including a conserved vascular smooth muscle cell program and cross-segment renal tubular programs, along with tissue-specialized endothelial adaptations and coordinated changes across cell types in select organs. Integration with human genomic data revealed model-specific and shared cell type-trait links. We prioritized a noncoding variant (rs28451064) and used genome editing to demonstrate its in vivo effect on blood pressure and allele-specific regulation of local genes. Our study provides a multimodel, cross-organ cellular resource for hypertension research.
『摘要』
高血压是导致疾病负担和死亡的主要原因。在此，我们对血管紧张素II处理的小鼠、Dahl盐敏感性大鼠和自发性高血压大鼠的六个器官和组织进行了单细胞分析，以研究高血压及终末器官损伤。我们确定了与血压和肾损伤相关的基因程序，包括保守的血管平滑肌细胞程序和跨节段肾小管程序，以及组织特异性内皮适应性改变和特定器官中细胞类型的协调变化。通过整合人类基因组数据，揭示了模型特异性和共享的细胞类型-性状关联。我们确定了一个非编码变异（rs28451064）为优先研究对象，并利用基因编辑技术证明了其对体内血压的影响以及对局部基因的等位基因特异性调控作用。我们的研究为高血压研究提供了多模型、跨器官的细胞资源。
『总结』
该研究对多种动物模型的多个器官进行单细胞分析，确定了与血压和肾损伤相关基因程序，整合人类基因组数据揭示关联，还发现一个非编码变异及其影响，为高血压研究提供细胞资源。
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8. 全范德华异质结构中的室温多铁性。
Room-temperature multiferroicity in all-van der Waals heterostructures.
『Abstract』Multiferroics host simultaneous and coupled ferroic orders, allowing disparate external stimuli to induce abrupt transformations in their structures and properties. Creating multiferroicity in two-dimensional (2D) van der Waals (vdW) platforms would add the elements of strong quantum confinement, enhanced quasiparticle excitations, and wide tunability to the capabilities of these systems. In this work, we constructed vdW heterostructures of ferromagnetic triiron gallium ditelluride (Fe3GaTe2) and ferroelectric copper indium thiophosphate (CuInP2S6) to integrate their respective orders. We observed strong interferroic coupling at room temperature by demonstrating ferroelectrically reconfigurable magnetic anisotropy of 2D Fe3GaTe2. The interferroic magnetoelectricity diminished with increasing Fe3GaTe2 thickness, revealing the interfacial nature of heterostructure multiferroicity. Our discovery of all-vdW heterostructure multiferroicity opens the door to the artificial assembly of vdW layers for designer 2D multiferroics.
『摘要』
多铁性材料同时具有耦合的铁性序，允许不同的外部刺激引发其结构和性质的突变。在二维（2D）范德华（vdW）体系中构建多铁性将为其功能增添强量子限制、增强的准粒子激发和广泛可调性等元素。本研究中，我们构建了铁磁性的三铁镓二碲化物（Fe3GaTe2）与铁电性的铜铟硫代磷酸盐（CuInP2S6）的范德华异质结构，以整合它们各自的铁性序。通过展示二维Fe3GaTe2的铁电可重构磁各向异性，我们在室温下观察到了强烈的铁序间耦合。随着Fe3GaTe2厚度的增加，铁序间磁电效应减弱，揭示了异质结构多铁性的界面特性。我们对全范德华异质结构多铁性的发现为人工组装范德华层以设计二维多铁性材料开辟了道路。
『总结』
研究构建了铁磁性与铁电性材料的二维范德华异质结构，观察到室温下的强烈铁序间耦合，且该效应随厚度增加而减弱，揭示了界面特性，为设计二维多铁性材料提供了新途径。
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9. 突破纹理压电陶瓷的性能瓶颈。
Overcoming the performance ceiling of textured piezoelectric ceramics.
『Abstract』Textured piezoelectric ceramics could deliver the ultrahigh piezoelectricity of single crystals while retaining the mechanical robustness and cost-effectiveness of conventional ceramics, but after decades of effort, their piezoelectricity has not approached that of single crystals. We exploited compositional flexibility of textured ceramics, a critical advantage over single-crystal counterparts, using a machine-learning approach. Our samarium (Sm)-doped Pb(In1/2Nb1/2)O3-Pb(Sc1/2Nb1/2)O3-PbTiO3 textured ceramics exhibited an ultrahigh piezoelectric coefficient (d33) of 1720 picocoulombs per newton and a Curie temperature of 250°C. These values are comparable to, or even surpass, those of state-of-the-art single crystals. In situ x-ray diffraction and Rayleigh analysis indicate that their exceptional piezoelectricity is predominantly intrinsic rather than driven by domain switching. Leveraging these textured ceramics, we fabricated a piezoelectric accelerator that exhibits not only higher sensitivity but also substantially better reliability than its single-crystal counterparts.
『摘要』
织构化压电陶瓷既能具备单晶材料的超高压电性，又能保持传统陶瓷的机械强度和成本优势。然而经过数十年的研究，其压电性能仍无法与单晶相媲美。我们利用机器学习方法开发了织构化陶瓷的成分灵活性这一关键优势（这是相对于单晶材料的重要突破点）。实验表明，钐(Sm)掺杂的Pb(In1/2Nb1/2)O3-Pb(Sc1/2Nb1/2)O3-PbTiO3织构化陶瓷展现出超高压电系数（d33）达1720皮库仑每牛顿，居里温度为250°C，这些指标已达到甚至超越当前最先进的单晶材料水平。原位X射线衍射和瑞利分析证实，其优异压电性主要源于本征特性而非畴壁运动主导。基于该织构化陶瓷开发的压电加速度计，在灵敏度显著提升的同时，可靠性较单晶器件实现质的飞跃。
『总结』
通过机器学习优化成分设计，织构化压电陶瓷首次实现与单晶相当的超高压电性能，且兼具高可靠性和低成本优势，相关加速度计应用验证了其实用价值。
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10. 通过核碰撞追踪重子数。
Tracking the baryon number with nuclear collisions.
『Abstract』Baryon quantum number is found to be conserved since baryogenesis in the early Universe. Conventionally, each fractionally charged valence quark is understood to carry one-third of a baryon number. An alternative hypothesis posits that baryon number is instead carried by a baryon junction-a nonperturbative, Y-shaped gluonic configuration. Neither scenario has been verified experimentally. The STAR Collaboration reports measurements at mid-rapidity of baryon number (B) over the electric charge number difference (∆Q) in isobar nuclear collisions, and the net-proton yield along rapidity in photonuclear collisions. A larger B/∆Q ratio and less asymmetric net-proton yield are observed than predicted from models assigning baryon number to valence quarks. These findings, corroborated by previous measurements in Au+Au collisions, disfavor the valence quark picture.
『摘要』
自早期宇宙重子生成以来，重子量子数被发现是守恒的。传统观点认为，每个带分数电荷的价夸克携带三分之一的重子数。另一种假设则提出，重子数是由一种非微扰的、Y形胶子构型——重子结来承载的。这两种设想均未得到实验验证。STAR合作组报告了在同位素核碰撞中，对重子数（B）与电荷数差值（∆Q）之比在中间快度区的测量结果，以及光核碰撞中沿快度方向的净质子产额。相较于将重子数赋予价夸克的模型预测，观测到更大的B/∆Q比值和更不对称的净质子产额。这些发现与之前金-金（Au+Au）碰撞中的测量结果相互印证，不支持价夸子图景。
『总结』
研究发现自早期宇宙重子生成后重子量子数守恒，有传统和另一关于重子数承载方式的两种设想且都未被证实，STAR合作组的测量显示更大B/∆Q比值等，与之前测量相互印证，不支持价夸子图景。
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11. 古新世-始新世极热事件期间高浓度二氧化碳导致森林树冠衰退
Forest canopy decline under elevated CO<sub>2</sub> during the Paleocene-Eocene Thermal Maximum.
『Abstract』Uncertainty remains regarding the impact of rapid anthropogenic warming on forest ecosystem structure, biodiversity, and function. As an analog, we reconstruct forest canopy density and compositional change in Wyoming, USA, through the Paleocene-Eocene Thermal Maximum (PETM), an interval of abrupt carbon increase and warming ~56 million years ago. We develop a proxy to quantify leaf area index and assess shifts in floral composition using palynomorphs. Forest canopies opened abruptly at onset of PETM warming, landscape erosion increased, and vegetation shifted from broad-leaved angiosperm to fern- and palm-dominated ecosystems. When combined with regional data, these patterns suggest that continental-scale changes in plant communities cause landscape destabilization. These shifts also have implications for multimillennial-scale hydrologic and carbon cycle feedbacks in the climate system.
『摘要』
快速人为变暖对森林生态系统结构、生物多样性和功能的影响仍存在不确定性。作为类比，我们通过古新世-始新世极热事件（PETM，约5600万年前碳含量和气温急剧上升的时期）重建了美国怀俄明州森林冠层密度和组成变化。我们开发了一种替代指标来量化叶面积指数，并利用孢粉形态评估植物群落组成的转变。在PETM变暖开始时，森林冠层突然变得稀疏，地表侵蚀加剧，植被从阔叶被子植物向以蕨类和棕榈为主的生态系统转变。结合区域数据后，这些模式表明，植物群落在大陆尺度的变化会导致景观不稳定化。这些转变还对气候系统中持续数千年的水文和碳循环反馈产生影响。
『总结』
快速人为变暖对森林生态系统影响不确定，研究通过古新世 - 始新世极热事件重建美国怀俄明州森林相关情况，发现该事件中森林冠层等有变化，且植物群落大陆尺度变化致景观不稳，还影响气候系统反馈。
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12. 编码感觉历史偏差的丘脑皮层回路。
A thalamocortical circuit encoding deviations from sensory history.
『Abstract』Prior expectations guide attention and support perceptual filtering during decision-making. In mice performing a visual discrimination task, choices depended on trial-by-trial differences between consecutive stimuli (|ΔDir|). We hypothesized that thalamic lateral posterior (LP; rodent pulvinar) projections to prefrontal areas such as the anterior cingulate cortex (ACC), previously implicated in selective attention and predictive processing, could support history-dependent evaluation of current sensory evidence. In this work, we report that optogenetic manipulations of LP-ACC axons disrupted history-dependent evaluation of current sensory evidence, producing |ΔDir|-dependent choice biases. Two-photon imaging showed that LP-ACC axons represented stimuli along a task-dependent low-dimensional curved manifold whose geometry scaled with |ΔDir|, emphasizing larger deviations from recent evidence. These findings identify the LP-ACC as a thalamocortical pathway that implements a contrastive, history-referenced representation of sensory evidence during decisions.
『摘要』
在决策过程中，先前期望会引导注意力并支持感知过滤。在执行视觉辨别任务的小鼠中，其选择取决于连续刺激之间的逐次差异（|ΔDir|）。我们假设，丘脑外侧后核（LP；啮齿动物丘脑枕）投射到前额叶区域（如前扣带回皮质ACC），鉴于这些区域先前已被证实与选择性注意和预测性处理有关，因此可能有助于对当前感觉证据进行基于历史记录的评估。在本研究中，我们发现光遗传学操纵LP-ACC轴突会破坏对当前感觉证据的历史依赖性评估，从而产生依赖于|ΔDir|的选择偏差。双光子成像显示，LP-ACC轴突沿着一个低维弯曲流形表示刺激，该流形的几何形状随|ΔDir|变化而缩放，强调了与近期证据的较大偏差。这些发现表明，LP-ACC是丘脑皮层通路，可在决策过程中实现对感觉证据的对比性、基于历史参考的表征。
『总结』
研究发现丘脑外侧后核投射到前扣带回皮质的通路在决策中对感觉证据进行基于历史的评估，光遗传学操纵此通路会破坏这种评估并产生选择偏差，双光子成像揭示了相关机制。
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13. 化石齿鳞揭示海洋生产力如何影响鲨鱼基线及恢复潜力。
Fossil denticles reveal how ocean productivity shapes shark baselines and recovery potential.
『Abstract』Shark populations on coral reefs have declined globally, but few baselines exist to quantify natural variability before human impact. Using fossil dermal denticles preserved in reef sediments, we reconstructed shark communities across the Isthmus of Panama before substantial exploitation [~7 to 3 thousand years ago (ka)] and recently (past century). We found differences in shark baselines and responses to fishing between the oceans on either side of the Isthmus. Reefs in the Pacific supported an ~20-fold higher shark abundance than Caribbean reefs before human impact. Caribbean shark populations-particularly pelagic species-have declined by 75% since the mid-Holocene, whereas their Pacific counterparts persisted over millennia despite higher fishing pressure. These contrasting trajectories are consistent with differences in oceanic productivity that dictate regional carrying capacities, highlighting the importance of incorporating oceanographic context into marine conservation targets.
『摘要』
全球范围内珊瑚礁上的鲨鱼种群数量有所下降，但几乎没有基线数据可用于量化人类影响之前的自然变化。我们利用保存在珊瑚礁沉积物中的化石皮肤齿，重建了巴拿马地峡在遭受大规模捕捞之前（约7000年至3000年前）和近期（过去一个世纪）的鲨鱼群落。我们发现，地峡两侧海洋中鲨鱼的基线水平及其对捕捞的反应存在差异。在人类活动影响前，太平洋珊瑚礁的鲨鱼丰度约为加勒比海珊瑚礁的20倍。自全新世中期以来，加勒比海的鲨鱼种群（尤其是远洋物种）减少了75%，而其太平洋同类尽管面临更大的捕捞压力，却延续了数千年之久。这些截然不同的演变轨迹与决定区域环境承载力的海洋生产力差异相吻合，凸显了在制定海洋保护目标时纳入海洋学背景的重要性。
『总结』
全球珊瑚礁鲨鱼种群减少，研究通过化石重建巴拿马地峡不同时期鲨鱼群落，发现太平洋与加勒比海鲨鱼基线和受捕捞影响情况不同，这凸显海洋生产力差异及将海洋学背景纳入海洋保护目标的重要性。
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14. 由促进剂驱动的重结晶获得高度织构化的钌。
Promoter-driven recrystallization affording highly textured ruthenium.
『Abstract』The electrical properties of polycrystalline materials are governed by crystallite characteristics and spatial arrangement. We grew ruthenium polycrystals with a near-complete out-of-plane preferred orientation and predominantly low-energy grain boundaries on amorphous dielectric substrates, without relying on epitaxial growth or lattice-matched conditions. Whereas prior studies used high-density, high-quality polycrystalline materials derived from high-purity sources, we exploited trace carbon as a transient promoter at grain boundaries, revealing that it generated transient free volume during recrystallization and thus facilitated atomic migration, driving the dynamic vertical and horizontal orientation of grains. Our findings provide microscopic insights into the engineering of grain boundary kinetics through controlled trace element incorporation. The developed strategy is applicable to other polycrystalline materials, offering versatility for advanced material design and applications.
『摘要』
多晶材料的电性能由晶粒特征和空间排列决定。我们在非晶介电衬底上生长出了具有近乎完全的面外择优取向且主要为低能晶界的钌多晶，此过程无需依赖外延生长或晶格匹配条件。先前的研究使用源自高纯度原料的高密度、高质量多晶材料，而我们利用微量碳作为晶界处的瞬态促进剂，发现其在再结晶过程中会产生瞬态自由体积，从而促进原子迁移，推动晶粒的动态垂直和水平取向。我们的研究结果为通过控制微量元素掺入来调控晶界动力学提供了微观层面的见解。所开发的策略适用于其他多晶材料，在先进材料设计与应用方面具有通用性。
『总结』
研究发现利用微量碳作瞬态促进剂可在非晶介电衬底上制备出特定取向的钌多晶，为调控晶界动力学提供微观见解，该策略适用性广。
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15. 东非及印度洋下方地幔深部的地球物理-地球化学联合分区图
A joint geophysical-geochemical deep-mantle zoning map beneath East Africa and the Indian Ocean.
『Abstract』Geochemical signatures of hotspot lavas suggest that their mantle sources are compositionally distinct, but their source locations remain elusive. Mapping hotspots to their deep origins is complicated by the presence of interconnected, low-seismic velocity networks in the mantle, where plumelike anomalies often deviate from vertical conduits. We propose a graph theory-based framework to systematically trace ensembles of plume paths using a high-resolution regional tomographic model. Applied to eight East African and Indian Ocean hotspots, our method identified clustered source zones near the core-mantle boundary. Multivariate analysis of the isotope ratios of hotspot-related basalts reveals a broadly similar clustering. Together, these independent observations provide a first-order joint geophysical-geochemical zoning map in this region, with at least three distinct domains within the African large low-shear-velocity province (LLSVP).
『摘要』
热点熔岩的地化特征表明，其地幔源区成分独特，但具体位置仍难以确定。由于地幔中存在相互连通的低地震波速网络，且羽状异常往往偏离垂直通道，将热点与其深部起源进行对应十分复杂。我们提出了一种基于图论的框架，利用高分辨率区域层析成像模型系统地追踪羽流路径集合。将该方法应用于东非和印度洋的八个热点时，我们的方法在核幔边界附近确定了聚集的源区。对与热点相关的玄武岩同位素比值进行的多元分析显示出了大致相似的聚类情况。这些独立的观测结果共同为该地区提供了首个一阶联合地球物理-地球化学分区图，其中非洲大低剪切波速省（LLSVP）内至少有三个不同的区域。
『总结』
热点熔岩地化特征显示其地幔源区成分独特但位置难寻，因地幔结构复杂定位困难，研究提出基于图论的框架追踪羽流路径，应用后确定源区并发现相关玄武岩同位素比值有相似聚类，得出该地区首个联合分区图及三个不同区域。
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16. 使用针对肝期后期的抗疟药物进行化学疫苗接种可诱导产生对疟疾的持久免疫力。
Chemovaccination with a late-liver-stage antimalarial induces durable immunity against malaria.
『Abstract』Plasmodium falciparum sporozoite vaccines, in which parasites are attenuated at the liver stage, provide high efficacy but require complex manufacture and intravenous administration of high sporozoite doses. We found that a single low-dose P. berghei sporozoite exposure (intravenous or mosquito bite) and treatment with a plasmepsin IX and X (PMIX/X) inhibitor, either WM382 or MK-7602, that produced "chemo-attenuated liver merozoites" (CALM) induced sterile immunity in mice for up to 21 months. Protection involved anti-circumsporozoite protein (CSP) antibodies and CD8+ T cells, including liver-resident memory subsets that recognized diverse antigens (SERA1, RPL6, GAP50, RNT, PHIST, S20, and RBP). WM382 also attenuated P. falciparum liver merozoites, and conservation of PMIX/X active sites supports pan-Plasmodium potential for preventing malaria. CALM vaccination merits clinical evaluation, including by natural mosquito exposure if long-acting injectable PMIX/X inhibitor formulations prove feasible.
『摘要』
在肝脏阶段使寄生虫减毒的恶性疟原虫子孢子疫苗具有高效性，但需要复杂的制造工艺和静脉注射高剂量子孢子。我们发现，单次低剂量的伯氏疟原虫子孢子暴露（静脉注射或蚊子叮咬）以及使用组织蛋白酶IX和X（PMIX/X）抑制剂WM382或MK-7602进行治疗，可产生“化学减毒肝脏裂殖子”（CALM），在小鼠体内诱导长达21个月的无菌免疫。保护作用涉及抗环子孢子蛋白（CSP）抗体和CD8+ T细胞，包括识别多种抗原（SERA1、RPL6、GAP50、RNT、PHIST、S20和RBP）的肝脏驻留记忆亚群。WM382还可使恶性疟原虫肝脏裂殖子减毒，且PMIX/X活性位点的保守性支持其预防疟疾的全疟原虫潜力。如果长效注射用PMIX/X抑制剂配方可行，CALM疫苗值得进行临床评估，包括通过自然蚊虫叮咬接种的方式。
『总结』
研究发现单次低剂量伯氏疟原虫子孢子暴露结合特定抑制剂治疗产生的CALM可在小鼠中诱导长期无菌免疫，相关机制涉及多种免疫成分，且该策略对恶性疟原虫也有潜在效果，若长效注射抑制剂可行则CALM疫苗值得临床评估。
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