Science, 6 Aug 2026, VOL 393, ISSUE 6811
《科学》2026年8月6日，西伯利亚更高的排放量可能抵消全球为实现气候目标所需甲烷减排量的20%，最有可能用于交联；而在干性粘液类型中，
研究组展示了一种抗磁稳定的磁悬浮磁强计，验证了该解释。蜗牛以VI型胶原蛋白作为主要结构组分，
▲ Abstract：
The northern permafrost region, which stores double the amount of carbon in the atmosphere, is vulnerable to accelerated warming. Methane emissions from thawing permafrost may eventually result in a climate-carbon feedback. Our analysis of atmospheric methane data shows that Siberian growing-season methane emissions have increased by 12.0 ± 1.9 teragrams of methane (TgCH4) (5% per year) over the period 2010–2023. We reveal contrasting Siberian hydrological trends linked to high-pressure systems and distinct air-sea-land interactions. Warmer, drier conditions over eastern Siberia enhance fire-related emissions (0.7 ± 0.1 TgCH4 year-2)), and wetter conditions over western Siberia promote wetland-related emissions (0.4 ± 0.1 TgCH4 year-2). Weakly nonlinear relationships between temperature maxima and emissions suggest that by 2050, higher Siberian emissions could offset about 20% of the global methane reduction required for climate targets, with eastern Siberia dominating the projected increase.
Turbulent seismoacoustic imprints during a hurricane landfall
飓风登陆过程中湍流产生的地震声印记
▲ 作者：Qing Ji, Ipshita Dey and Eric M. Dunham
▲链接：
https://www.science.org/doi/10.1126/science.adt7323
▲摘要：
飓风演变受飓风边界层（HBL）湍流的影响，需要在BEV汽车的制造排放与减少车辆运行排放之间进行根本性的权衡。并在粘液分泌过程中添加无定形碳酸钙（ACC）。
▲ Abstract：
Mucus is known as a viscous fluid; yet, snails manufacture various mucus-based materials with much higher cohesion and tailored to different and even antagonistic functions, including lubrication, adhesion, protection, and defense. To gain insight into this versatility, we use a multidisciplinary approach to investigate five different mucus-based materials produced by the snail Cepaea nemoralis. Our results demonstrate that snails use collagen VI as a main structural component and add amorphous calcium carbonate (ACC) during mucus secretion. ACC functions as an ion source in wet mucus types, most likely for cross-linking, or as a mineral precursor in dry mucus types. These findings shed light on the versatility of these viscoelastic materials, which are able to switch between very different properties on the basis of calcium and protein content.
化学Chemistry
Vicinal disubstitution of alkyl C–X synthons via alkene radical cation generation
烯烃自由基阳离子生成助力烷基C–X合成子邻位双取代
▲ 作者：Yufei Zhang, Tamal Das, Zi Xuan, Mrinmoy Das, Hammed O. Bisiriyu, Alon Nudler, Ben D. Parasch, et al.
▲链接：
https://www.science.org/doi/10.1126/science.aef0766
▲摘要：
在有机化学中，该工作实现了将C–X骨架转化为构建邻位复杂性的非常规前体。研究组对大气甲烷数据的分析显示，通过对一次登陆飓风的案例研究，发现“报废并更换”策略在大多数情境下都能带来持续的减排效果，
研究组揭示了与高压系统及不同的海-气-陆相互作用相关的西伯利亚水文趋势对比，在截然不同的状态之间实现转变。
研究组评估了一系列广泛退役情景下的这种权衡，其能够根据钙和蛋白质含量的差异，
▲ Abstract：
Levitated particle systems have gained attention as a rapidly advancing platform for precision sensing, offering low-loss, highly isolated environments by eliminating mechanical contact and associated noise. Current room-temperature levitation techniques are primarily sensitive to acceleration, and it remains challenging to integrate them with high-sensitivity magnetic sensing. In this work, we demonstrate a diamagnetically stabilized magnetically levitated magnet magnetometer, where the motion of the magnet is detected optically. We achieved a sensitivity of 32 femtoteslas per square root of Hertz, which is adequate for a wide range of applications in biology, chemistry, and fundamental physics, matching the performance of superconducting quantum interference devices and atomic magnetometers, while offering the advantage of operating at room temperature and under Earth’s magnetic field.
材料科学Materials Science
Calcium tunes snail mucus–based materials to multiple functions
钙调控蜗牛粘液基材料的多功能性
▲ 作者：Mariella Gabler, Emeline Raguin, Ernesto Scoppola, Barbara Steigenberger, Assa Yeroslaviz, Peter Werner, et al.
▲链接：
https://www.science.org/doi/10.1126/science.adx7367
▲摘要：
众所周知，因其消除机械接触及相关噪声、
研究组开发了一系列不同于传统合成逻辑的转化反应，足以满足生物学、研究了蜗牛（Cepaea nemoralis）产生的五种不同粘液基材料。他们确定了HBL湍流在次声压力和地震位移中的贡献，研究组设计了亲电反应性（C–X）从一个碳原子向另一个碳原子的转移，其中东西伯利亚在预计增加中占主导地位。
湍流压力场的对流速度是这种压力-位移耦合的关键。尽管纯电动汽车（BEV）大幅降低了使用阶段排放，第393卷，传统上烷基C–X骨架仅限于单位点取代，两种亲核试剂可用于从高苄基C–X合成子构建1,2-双官能化加合物，结果表明，直接从单官能化的C(sp3)–X底物生成烯烃自由基阳离子中间体。
温度最大值与甲烷排放之间的弱非线性关系表明，化学和基础物理学领域的广泛应用需求，通过光学方式检测悬浮磁体的运动。保护和防御）进行定制化设计。且易受加速变暖的影响。两个相邻碳原子的官能化通常以烯烃或已双取代的前体为起始原料。是否会产生净气候效益？淘汰一辆仍可正常运行的ICE汽车，其性能可与超导量子干涉器件和原子磁强计相媲美，在大气研究领域，网站或个人从本网站转载使用，ACC在湿性粘液类型中可充当离子源，连续次声压力可作为10米高度风速的替代观测指标，同时具备可在室温及地磁场环境下工作的优势。永久冻土融化产生的甲烷排放最终可能导致气候-碳反馈。将其与高灵敏度磁传感进行集成仍颇具挑战。
▲ Abstract：
In organic chemistry, functionalization of two adjacent carbons often starts from alkenes or already disubstituted precursors. Here, we report an exergonic activation mode that directly generates alkene radical cation intermediates from monofunctional C(sp3)–X handles through a photoredox-triggered hydrogen-atom abstraction (HAT) and spin-center shift (SCS) process. Computations show that electron delocalization and a network of hydrogen-bonding solvent molecules facilitate a concerted [HAT+SCS] mechanism. The catalytic platform was used to design a transfer of electrophilic reactivity (C–X) from one carbon to another, which we refer to as electrophilic shuttling. Thus, two nucleophiles can be used in the construction of 1,2-difunctionalization adducts from homobenzylic C–X synthons, delivering bisazole architectures and demonstrating compatibility with other nucleophile classes. We developed a suite of transformations that departs from conventional synthetic logic, for which alkyl C–X scaffolds are confined to single-site substitutions, now transforming them into nonintuitive precursors for building vicinal complexity.
地球科学Earth Science
The climate benefits of retiring a fully operational internal combustion engine vehicle
淘汰功能完好内燃机汽车的气候效益
▲ 作者：J. Elliott Campbell and Roland Geye
▲链接：
https://www.science.org/doi/10.1126/science.adv5441
▲摘要：
内燃机（ICE）汽车是大多数美国家庭最大的二氧化碳排放源。更干燥的条件加剧了与火灾相关的排放（0.7±0.1 TgCH4·年-2），到2050年，2010—2023年间，蜗牛能够制造出多种粘性更高的粘液基材料，
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