編譯|未玖
Nature, 3 July 2025, Volume 643, Issue 8070
《自然》2025年7月3日，第643卷，8070期
天文學Astronomy
Carbonate formation and fluctuating habitability on Mars
火星上碳酸鹽的形成和宜居性的波動
▲ 作者：Edwin S. Kite, Benjamin M. Tutolo, Madison L. Turner, Heather B. Franz, David G. Burtt, Thomas F. Bristow, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09161-1
▲摘要：火星表面宜居性喪失的原因尚不明確，同位素數據表明存在碳酸鹽的“缺失匯”。火星沉積巖（包括蓋爾隕石坑內約4千米厚的地層）記錄了表層和淺層地下液態水的古氣候。這些水體是間歇性的，空間分布零散且不連貫，且在火星地質史后期一直持續存在。如果其沉積巖形成如地球般將二氧化碳封存為豐富的碳酸鹽（最近在蓋爾坑原位證實了這一點），那么這些特征便可合理解釋。
研究表明，太陽光度、液態水和碳酸鹽形成之間的負反饋可以解釋火星零散綠洲的存在。在該模型中，太陽光度的增強促進了液態水的穩定性，從而形成碳酸鹽，降低了大氣二氧化碳的分壓，反而限制了液態水。混沌軌道攝動調控干濕循環。該負反饋將液態水限制在綠洲中，使火星自調節為一個沙漠星球。研究將融雪建模為水源，但該反饋也可將地下水作為水源。模型輸出表明，蓋爾坑完整記錄了表層和近表層環境中液態水穩定性的預期主要事件。最終，大氣厚度接近水的三相點，削弱了液態水的持續穩定性，從而降低了地表環境中的宜居性。研究假設在蓋爾坑發現的碳酸鹽含量具有代表性，因此該觀點屬于可檢驗假說而非確鑿證據。
▲ Abstract： The cause of Mars’s loss of surface habitability is unclear, with isotopic data suggesting a ‘missing sink’ of carbonate. Past climates with surface and shallow-subsurface liquid water are recorded by Mars’s sedimentary rocks, including strata in the approximately 4-km-thick record at Gale Crater. Those waters were intermittent, spatially patchy and discontinuous, and continued remarkably late in Mars’s history—attributes that can be understood if, as on Earth, sedimentary-rock formation sequestered carbon dioxide as abundant carbonate (recently confirmed in situ at Gale). Here we show that a negative feedback among solar luminosity, liquid water and carbonate formation can explain the existence of intermittent Martian oases. In our model, increasing solar luminosity promoted the stability of liquid water, which in turn formed carbonate, reduced the partial pressure of atmospheric carbon dioxide and limited liquid water. Chaotic orbital forcing modulated wet–dry cycles. The negative feedback restricted liquid water to oases and Mars self-regulated as a desert planet. We model snowmelt as the water source, but the feedback can also work with groundwater as the water source. Model output suggests that Gale faithfully records the expected primary episodes of liquid water stability in the surface and near-surface environment. Eventually, atmospheric thickness approaches water’s triple point, curtailing the sustained stability of liquid water and thus habitability in the surface environment. We assume that the carbonate content found at Gale is representative, and as a result we present a testable idea rather than definitive evidence.
物理學Physics
Energy–speed relationship of quantum particles challenges Bohmian mechanics
量子粒子的能量-速度關系挑戰玻姆力學
▲ 作者：Violetta Sharoglazova, Marius Puplauskis, Charlie Mattschas, Chris Toebes & Jan Klaers
▲鏈接：
https://www.nature.com/articles/s41586-025-09099-4
▲摘要：經典力學將粒子動能（因其運動而保持的能量）描述為恒正值。相比之下，量子力學則用波函數描述粒子運動，其中可能出現局域負動能區域。當波函數振幅顯著衰減時，就會發生這種現象，通常與量子隧穿效應有關。研究分析了兩個耦合波導系統中粒子的量子力學運動，其中波導間的粒子數轉移充當計時器，從而確定了粒子沿波導軸的速度。通過將該方案應用于反射勢壘的指數衰減量子態，研究確定了具有局域負動能粒子的能量-速度關系。研究發現粒子的能量越低（即局域動能越負），勢壘內測量的速度就越高。
該發現為正在進行的隧穿時間爭議提供了新見解，可被視為對量子力學中玻姆軌跡的測試。對于后者，研究組發現所測的能量-速度關系與玻姆力學中引導方程所假設的粒子動力學不一致。
▲ Abstract： Classical mechanics characterizes the kinetic energy of a particle, the energy it holds due to its motion, as consistently positive. By contrast, quantum mechanics describes the motion of particles using wave functions, in which regions of negative local kinetic energy can emerge. This phenomenon occurs when the amplitude of the wave function experiences notable decay, typically associated with quantum tunnelling. Here, we investigate the quantum mechanical motion of particles in a system of two coupled waveguides, in which the population transfer between the waveguides acts as a clock, allowing particle speeds along the waveguide axis to be determined. By applying this scheme to exponentially decaying quantum states at a reflective potential step, we determine an energy–speed relationship for particles with negative local kinetic energy. We find that the smaller the energy of the particles—in other words, the more negative the local kinetic energy—the higher the measured speed inside the potential step. Our findings contribute to the ongoing tunnelling time debate and can be viewed as a test of Bohmian trajectories in quantum mechanics. Regarding the latter, we find that the measured energy–speed relationship does not align with the particle dynamics postulated by the guiding equation in Bohmian mechanics.
材料科學Materials Science
Efficient near-infrared harvesting in perovskite–organic tandem solar cells
鈣鈦礦-有機疊層太陽能電池中的高效近紅外采集
▲ 作者：Zhenrong Jia, Xiao Guo, Xinxing Yin, Ming Sun, Jiawei Qiao, Xinyu Jiang, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09181-x
▲摘要：鈣鈦礦和有機半導體的寬帶隙可調性使鈣鈦礦-有機疊層太陽能電池的開發具有很高的理論效率。然而，已報道的鈣鈦礦-有機疊層太陽能電池的認證效率仍低于單結鈣鈦礦太陽能電池，主要是因為窄帶隙有機子電池中的近紅外光生電流不足。
研究設計并合成了一種不對稱的非富勒烯受體（NFA）P2EH-1V，其特征是單側共軛π橋，可在保持理想激子解離和納米形貌的同時將光學帶隙降低到1.27?eV。瞬態吸收光譜證實了從P2EH-1V向給體PM6的有效空穴轉移。基于P2EH-1V的器件在保持電荷產生效率的情況下，將非輻射電壓損失降低了0.20?eV。 研究實現了17.9%的有機底部電池效率，短路電流密度（Jsc）高達28.60 mA cm?2。此外還最大限度地減少了界面復合損失，使鈣鈦礦頂部電池能夠實現優異的1.37?V開路電壓（Voc）和85.5%的填充因子（FF）。這些進展使得鈣鈦礦-有機疊層太陽能電池在大于1 cm2的孔徑面積上實現了26.7%的創紀錄效率（經認證為26.4%）。
▲ Abstract： The broad bandgap tunability of both perovskites and organic semiconductors enables the development of perovskite–organic tandem solar cells with promising theoretical efficiency. However, the certified efficiencies of reported perovskite–organic tandem solar cells remain lower than those of single-junction perovskite solar cells, primarily because of insufficient near-infrared photocurrent in narrow-bandgap organic subcells. Here we design and synthesize an asymmetric non-fullerene acceptor (NFA), P2EH-1V, featuring a unilateral conjugated π-bridge to reduce the optical bandgap to 1.27?eV while maintaining ideal exciton dissociation and nanomorphology. Transient absorption spectroscopy confirms efficient hole transfer from P2EH-1V to the donor PM6. Devices based on P2EH-1V exhibit reduced non-radiative voltage losses of 0.20?eV without compromising charge-generation efficiency. We achieve a 17.9% efficiency for the organic bottom cell, with a high short-circuit current density (Jsc) of 28.60?mA?cm?2. Furthermore, we minimize interface recombination losses, enabling the perovskite top cell to achieve an impressive open-circuit voltage (Voc) of 1.37?V and a fill factor (FF) of 85.5%. These advancements result in perovskite–organic tandem solar cells achieving a record efficiency of 26.7% (certified at 26.4%) over an aperture area greater than 1?cm2.
人工智能Artificial Intelligence
Computer-vision research powers surveillance technology
計算機視覺研究助力監控技術
▲ 作者：Pratyusha Ria Kalluri, William Agnew, Myra Cheng, Kentrell Owens, Luca Soldaini & Abeba Birhane
▲鏈接：
https://www.nature.com/articles/s41586-025-08972-6
▲ 摘要： 越來越多的學者、政策制定者和基層群體認為，人工智能（AI）研究（尤其是計算機視覺研究）已成為開發和推動大規模監控的核心驅動力。然而，從計算機視覺運用到監控的途徑仍然存在爭議。
研究實證說明了監控AI技術鏈路的性質和范圍，揭示了計算機視覺領域和監控領域之間密切關系的廣泛證據。通過對計算機視覺研究論文和引用專利的分析，他們發現這些文獻中的大多數都能夠定位人體和身體部位。
將1990年代與2010年代進行比較，研究觀察到與下游監控專利相關的計算機視覺論文數量增長了五倍。此外，該研究結果挑戰了只有少數不良實體能夠進行監控的觀念。相反，研究發現人體目標鎖定已在整個領域常態化。考慮到混淆模式，這種常態化尤其引人注目。
研究揭示模糊的語言幫助實現避免直接提及以人體為目標，例如，通過將人類稱為“對象”進行規范化研究，而無需特別考慮。該研究結果表明計算機視覺研究和監控之間存在著深度綁定。
▲ Abstract： An increasing number of scholars, policymakers and grassroots communities argue that artificial intelligence (AI) research—and computer-vision research in particular—has become the primary source for developing and powering mass surveillance. Yet, the pathways from computer vision to surveillance continue to be contentious. Here we present an empirical account of the nature and extent of the surveillance AI pipeline, showing extensive evidence of the close relationship between the field of computer vision and surveillance. Through an analysis of computer-vision research papers and citing patents, we found that most of these documents enable the targeting of human bodies and body parts. Comparing the 1990s to the 2010s, we observed a fivefold increase in the number of these computer-vision papers linked to downstream surveillance-enabling patents. Additionally, our findings challenge the notion that only a few rogue entities enable surveillance. Rather, we found that the normalization of targeting humans permeates the field. This normalization is especially striking given patterns of obfuscation. We reveal obfuscating language that allows documents to avoid direct mention of targeting humans, for example, by normalizing the referring to of humans as ‘objects’ to be studied without special consideration. Our results indicate the extensive ties between computer-vision research and surveillance.
Controlling diverse robots by inferring Jacobian fields with deep networks
通過深度網絡推斷雅可比場來操控多種機器人
▲ 作者：Sizhe Lester Li, Annan Zhang, Boyuan Chen, Hanna Matusik, Chao Liu, Daniela Rus, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09170-0
▲摘要：反映自然生物體的復雜結構和多樣化功能是機器人技術的長期挑戰。現代制造技術極大擴展了硬件的可行性，但使用這些系統需要控制軟件將所需的動作轉換為驅動指令。
傳統機器人可很容易地建模為由關節連接的剛性連桿，但建模和控制仿生機器人仍面臨挑戰。這些機器人通常很柔軟，或由幾種材料制成，缺乏傳感能力，并且可能會隨著使用而損耗其材料特性。
研究介紹了一種使用深度神經網絡將機器人的視頻流映射到其視覺運動雅可比場（3D點云對機器人致動器的靈敏度）的策略。該方法僅需要一個攝像頭就可以控制機器人，對機器人的材料、驅動或傳感沒有任何預設，且通過觀察隨機命令的執行，在沒有專家干預的情況下進行自主訓練。
該研究在一套致動、材料、制造和成本方面各不相同的多樣化機器人操作器上演示了該策略，最終實現了精確的閉環控制，并還原了每個機器人的因果動力學結構。由于該策略使用通用相機作為唯一傳感器來實現機器人控制，研究預計該工作將拓寬機器人系統的設計空間，并有望降低機器人自動化門檻。
▲ Abstract： Mirroring the complex structures and diverse functions of natural organisms is a long-standing challenge in robotics. Modern fabrication techniques have greatly expanded the feasible hardware, but using these systems requires control software to translate the desired motions into actuator commands. Conventional robots can easily be modelled as rigid links connected by joints, but it remains an open challenge to model and control biologically inspired robots that are often soft or made of several materials, lack sensing capabilities and may change their material properties with use. Here, we introduce a method that uses deep neural networks to map a video stream of a robot to its visuomotor Jacobian field (the sensitivity of all 3D points to the robot’s actuators). Our method enables the control of robots from only a single camera, makes no assumptions about the robots’ materials, actuation or sensing, and is trained without expert intervention by observing the execution of random commands. We demonstrate our method on a diverse set of robot manipulators that vary in actuation, materials, fabrication and cost. Our approach achieves accurate closed-loop control and recovers the causal dynamic structure of each robot. Because it enables robot control using a generic camera as the only sensor, we anticipate that our work will broaden the design space of robotic systems and serve as a starting point for lowering the barrier to robotic automation.
化學Chemistry
One-carbon homologation of alkenes 烯烴的單碳同系物
▲ 作者：Marcus C. Grocott & Matthew J. Gaunt
▲鏈接：
https://www.nature.com/articles/s41586-025-09159-9
▲ 摘要： 單碳同系物是結構相關且功能相似的有機分子，其鏈長僅相差一個亞甲基（-CH2-）單元。在包括藥劑、天然產物、農用化學品、香料和石油產品的許多種類分子中，同系物成員在不同化合物之間表現出的細微物理化學特征差異可能會使其功能顯著分化。
因此，高效合成同系物是分子發現計劃中的一項重要策略。盡管幾種官能團的同系化策略是可行的，但烯烴中單碳鏈延伸的直接和通用方法仍是一個合成難點。
研究報道了一種催化單碳同系物的工藝，對簡單和復雜分子中的許多類烯烴都適用。通過利用一種新型多功能烯丙基砜試劑的本征反應性（一種包括交叉復分解和裂解-反烯級聯的簡化一鍋法工藝），他們將一個亞甲基單元插入烯烴鏈中。
將該工藝應用于幾個結構和功能復雜的分子中，研究展示了這種實際轉化如何產生以前無法合成的環孢素A同系物。這些同系物表現出可調的藥理學和生物學特性，有望作為親環蛋白抑制劑（在許多疾病領域具有巨大潛力的靶標）的候選先導物。
▲ Abstract： One-carbon homologues are structurally related and functionally identical organic molecules whose chain lengths differ by a single methylene (–CH2–) unit. Across many classes of molecule—including pharmaceutical agents, natural products, agrochemicals, fragrances and petroleum products—the physicochemical characteristics exhibited by members of a homologous series subtly differ from one compound to another, which can impart remarkable differences to their function. The efficient generation of homologues is, therefore, an important strategy in molecular discovery programmes. Despite the availability of homologation strategies for several functional groups, direct and general methods for one-carbon chain extension in alkenes remain an unmet synthetic need. Here we report a catalytic one-carbon homologation process that is effective for many classes of alkene in simple and complex molecules. By leveraging the intrinsic reactivity of a new multifaceted allylsulfone reagent, a streamlined one-pot process, involving cross-metathesis and a fragmentation–retro-ene cascade, formally inserts a single methylene unit into the alkene chain. Among the applications of this process to several structurally and functionally complex molecules, we demonstrate how this practical transformation generates previously unexplored homologues of cyclosporine A. These homologues exhibit modulated pharmacological and biological properties and could provide promising leads as cyclophilin inhibitors, a target that has great potential in many disease areas.
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