编译|未玖
nature, 17 october 2024, volume 634, issue 8034
《自然》2024年10月17日，第634卷，8034期
天文学astronomy
young asteroid families as the primary source of meteorites
年轻的小行星族是陨石的主要来源
▲ 作者：m. bro, p. vernazza, m. marsset, f. e. demeo, r. p. binzel, d. vokrouhlicky, et al.
▲链接：
https://www.nature.com/articles/s41586-024-08006-7
▲摘要：
了解明亮流星及其陨石样本的起源是天文学中最古老的问题之一，在更大尺度上对人类产生影响。到目前为止，只有大约6%的陨石坠落与其来源（月球、火星或小行星（4）灶神星）有密切关联。
研究组发现大约70%的陨石起源于最近发生在580万年前、760万年前和不到4000万年前的三次d > 30千米小行星的分裂。这些分裂主要发生在著名的karin小行星族、著名且古老的koronis小行星族和massalia小行星族，是h和l普通球粒陨石在陨石坠落中占主导地位的起源。
这些年轻的小行星族在所有主带小行星中都具有独特的高丰度小碎片。其大小—频率分布在几千万年内仍保持陡峭，暂时超过了最大的古老小行星族（例如花神星和灶神星）产生的米级碎片。支持性证据包括相关尘埃带的存在、h球粒陨石的宇宙射线暴露年龄以及陨石的大气前轨道分布。
▲ abstract：
understanding the origin of bright shooting stars and their meteorite samples is among the most ancient of astronomy-related questions, which at larger scales has human consequences. as of today, only approximately 6% of meteorite falls have been firmly linked to their sources (moon, mars or asteroid (4) vesta). here we show that approximately 70% of meteorites originate from three recent break-ups of d > 30 km asteroids that occurred 5.8, 7.6 and less than about 40 myr ago. these break-ups, including the well-known karin family, took place in the prominent yet old koronis and massalia families and are at the origin of the dominance of h and l ordinary chondrites among meteorite falls. these young families are distinguished among all main belt asteroids by having a uniquely high abundance of small fragments. their size–frequency distribution remained steep for a few tens of millions of years, exceeding temporarily the production of metre-sized fragments by the largest old asteroid families (for example, flora and vesta). supporting evidence includes the existence of associated dust bands, the cosmic-ray exposure ages of h-chondrite meteorites and the distribution of the pre-atmospheric orbits of meteorites.
the massalia asteroid family as the origin of ordinary l chondrites
马萨利亚小行星族是普通l球粒陨石的起源
▲ 作者：m. marsset, p. vernazza, m. bro, c. a. thomas, f. e. demeo, b. burt, et al.
▲链接：
https://www.nature.com/articles/s41586-024-08007-6
▲摘要：
对中奥陶纪石灰岩和地球撞击坑中微陨石的研究表明，大约4.66亿年前，我们的星球见证了普通l球粒陨石物质的大量坠落，这可能是奥陶纪冰河时代和生物多样性重大转变的起源。主带中一颗大型小行星的解体很可能是这次大规模撞击的原因。目前，这种解体产生的物质仍然主导着陨石坠落（占所有坠落物的20%以上）。
研究组提供了光谱观测和动力学证据，表明马萨利亚小行星族碰撞是这场灾难性事件的唯一可信来源，也是当今地球上坠落的最丰富陨石类别。这个小行星族正好位于内带，在低倾角轨道上，这与观测到的l—球粒陨石样近地天体和集中在1.4°的行星际尘埃分布相一致。
▲ abstract：
studies of micrometeorites in mid-ordovician limestones and impact craters on earth indicate that our planet witnessed a massive infall of ordinary l chondrite material about 466 million years ago that may have been at the origin of an ordovician ice age and major turnover in biodiversity. the breakup of a large asteroid in the main belt is the likely cause of this massive infall. currently, material originating from this breakup still dominates meteorite falls (>20% of all falls). here we provide spectroscopic observations and dynamical evidence that the massalia collisional family is the only plausible source of this catastrophic event and the most abundant class of meteorites falling on earth today. this family of asteroids is suitably located in the inner belt, at low-inclination orbits, which corresponds to the observed distribution of l-chondrite-like near-earth objects and interplanetary dust concentrated at 1.4°.
材料科学material sciences
robust chemical analysis with graphene chemosensors and machine learning
石墨烯化学传感器和机器学习助力稳健化学分析
▲ 作者：andrew pannone, aditya raj, harikrishnan ravichandran, sarbashis das, ziheng chen, collin a. price, et al.
▲链接：
https://www.nature.com/articles/s41586-024-08003-w
▲摘要：
离子敏感场效应晶体管（isfets）已成为化学传感应用中不可或缺的工具。isfets通过将化学溶液组成的变化转换成电信号来运行，使其成为环境监测、医疗诊断和工业过程控制的理想选择。isfet技术的最新进展（包括功能化多路复用阵列和先进数据分析）提高了其性能。
研究组阐明了结合机器学习算法来构建预测模型的优势，该模型使用isfet传感器生成的广泛数据集来进行分类和量化任务。这种整合也为isfet的工作提供了超越人类专业知识的新视角。
此外，该策略还克服了与循环间、传感器间和芯片间变化相关的实际难题，为isfet在商业应用中的广泛采用铺平了道路。具体而言，研究组使用非功能化石墨烯基isfet阵列生成的数据来训练人工神经网络，这些神经网络具有识别食品欺诈、食品腐败和食品安全问题的卓越能力。
研究组预计，紧凑、节能和可重复使用的石墨烯基isfet技术与稳健机器学习算法的融合，有可能彻底改变精细化学和环境变化的检测，提供适用于广谱应用的快速、数据驱动的见解。
▲ abstract：
ion-sensitive field-effect transistors (isfets) have emerged as indispensable tools in chemosensing applications. isfets operate by converting changes in the composition of chemical solutions into electrical signals, making them ideal for environmental monitoring, healthcare diagnostics and industrial process control. recent advancements in isfet technology, including functionalized multiplexed arrays and advanced data analytics, have improved their performance. here we illustrate the advantages of incorporating machine learning algorithms to construct predictive models using the extensive datasets generated by isfet sensors for both classification and quantification tasks. this integration also sheds new light on the working of isfets beyond what can be derived solely from human expertise. furthermore, it mitigates practical challenges associated with cycle-to-cycle, sensor-to-sensor and chip-to-chip variations, paving the way for the broader adoption of isfets in commercial applications. specifically, we use data generated by non-functionalized graphene-based isfet arrays to train artificial neural networks that possess a remarkable ability to discern instances of food fraud, food spoilage and food safety concerns. we anticipate that the fusion of compact, energy-efficient and reusable graphene-based isfet technology with robust machine learning algorithms holds the potential to revolutionize the detection of subtle chemical and environmental changes, offering swift, data-driven insights applicable across a wide spectrum of applications.
化学chemistry
reductive alkyl–alkyl coupling from isolable nickel–alkyl complexes
可分离镍-烷基配合物的还原烷基-烷基偶联
▲ 作者：samir al zubaydi, shivam waske, volkan akyildiz, hunter f. starbuck, mayukh majumder, curtis e. moore, et al.
▲链接：
https://www.nature.com/articles/s41586-024-07987-9
▲摘要：
两种烷基亲电试剂的选择性交叉偶联以构建复杂分子仍是有机合成中的一个挑战。已知的反应针对特定亲电试剂进行优化，不适用于常见烷基构建单元（如胺、羧酸和卤化物）产生的可互换变化的亲电底物。这些局限性限制了可被改性的烷基底物类型，并最终限制了可以探索的化学空间。
研究组报道了解决这些局限性的通用策略，以实现烷基—烷基交叉偶联反应的组合方法。这种方法依赖于发现异常持久的ni（烷基）配合物，这些配合物可通过烷基卤化物、氧化还原活性酯或吡啶鎓盐的氧化加成直接形成。所得烷基配合物可被分离或直接伸缩至与第二个烷基亲电试剂偶联，这代表了此前未知的交叉选择反应。
通过脱卤、脱羧或脱胺基偶联的各种组合，氨基酸、天然产物、药物和类药物构建块的快速多样化展示了这种合成能力的实用性。除应用范围广泛外，这项工作还通过晶体学分析、立体化学探针和光谱研究，为合成相关ni（烷基）配合物的有机金属化学提供了见解。
▲ abstract：
the selective cross-coupling of two alkyl electrophiles to construct complex molecules remains a challenge in organic synthesis. known reactions are optimized for specific electrophiles and are not amenable to interchangeably varying electrophilic substrates that are sourced from common alkyl building blocks, such as amines, carboxylic acids and halides. these limitations restrict the types of alkyl substrate that can be modified and, ultimately, the chemical space that can be explored. here we report a general solution to these limitations that enables a combinatorial approach to alkyl–alkyl cross-coupling reactions. this methodology relies on the discovery of unusually persistent ni(alkyl) complexes that can be formed directly by oxidative addition of alkyl halides, redox-active esters or pyridinium salts. the resulting alkyl complexes can be isolated or directly telescoped to couple with a second alkyl electrophile, which represent cross-selective reactions that were previously unknown. the utility of this synthetic capability is showcased in the rapid diversification of amino acids, natural products, pharmaceuticals and drug-like building blocks by various combinations of dehalogenative, decarboxylative or deaminative coupling. in addition to a robust scope, this work provides insights into the organometallic chemistry of synthetically relevant ni(alkyl) complexes through crystallographic analysis, stereochemical probes and spectroscopic studies.
electrocatalytic reductive deuteration of arenes and heteroarenes
芳烃和杂芳烃的电催化还原氘代反应
▲ 作者：faxiang bu, yuqi deng, jie xu, dali yang, yan li, wu li, et al.
▲链接：
https://www.nature.com/articles/s41586-024-07989-7
▲摘要：
氘在有机分子中的掺入在药物化学和材料科学中应用广泛。例如，氘化药物austedo、donafenib和sotyktu最近已获批准。有多种方法可以合成高氘掺入的氘代化合物。然而，芳烃（普遍存在的化学原料）还原氘代至饱和环化合物的方法鲜能实现。
研究组描述了一种可扩展、通用的电催化方法，使用制备的氮掺杂电极和氧化氘（d2o）进行（杂）芳烃的还原性氘代和氘代脱氟，得到全氘代和饱和氘碳产物。该策略已成功应用于13种高氘代药物分子的合成。
机理研究表明，在氮掺杂钌电极存在下，由d2o电解产生的钌—氘物种是直接还原芳香族化合物的关键中间体。这种制备高氘标记饱和（杂）环化合物的快速且经济高效的方法可应用于药物开发和代谢研究。
▲ abstract：
the incorporation of deuterium in organic molecules has widespread applications in medicinal chemistry and materials science. for example, the deuterated drugs austedo, donafenib and sotyktu have been recently approved. there are various methods for the synthesis of deuterated compounds with high deuterium incorporation. however, the reductive deuteration of aromatic hydrocarbons—ubiquitous chemical feedstocks—to saturated cyclic compounds has rarely been achieved. here we describe a scalable and general electrocatalytic method for the reductive deuteration and deuterodefluorination of (hetero)arenes using a prepared nitrogen-doped electrode and deuterium oxide (d2o), giving perdeuterated and saturated deuterocarbon products. this protocol has been successfully applied to the synthesis of 13 highly deuterated drug molecules. mechanistic investigations suggest that the ruthenium–deuterium species, generated by electrolysis of d2oin the presence of a nitrogen-doped ruthenium electrode, are key intermediates that directly reduce aromatic compounds. this quick and cost-effective methodology for the preparation of highly deuterium-labelled saturated (hetero)cyclic compounds could be applied in drug development and metabolism studies.
地球科学earth science
jet stream controls on european climate and agriculture since 1300 ce
自公元1300年以来，大气急流对欧洲气候和农业的影响
▲ 作者：guobao xu, ellie broadman, isabel dorado-lián, lara klippel, matthew meko, ulf büntgen, et al.
▲链接：
https://www.nature.com/articles/s41586-024-07985-x
▲摘要：
大气急流是北半球中纬度地区气候变化的重要动力驱动因素。北大西洋—欧洲地区夏季急流纬度（eu jsl）位置的现代变化促进了欧洲西北部和东南部之间气压、温度、降水和干旱的双极模式。人们对eu jsl变率及其对区域极端气候和社会事件的影响知之甚少，特别是在人为变暖之前。
基于三个温度敏感的欧洲树木年轮记录，研究组重建了公元1300~2004年间夏季eu jsl的年际变化（r2= 38.5%），并将其与独立的历史气候记录和社会记录（如葡萄收成、粮食价格、瘟疫和人类死亡率）进行了比较。
研究组展示了公元1300年来与eu jsl变率相关的对比鲜明的夏季极端气候，以及生物物理、经济和人口影响，包括野火和流行病。根据对急流行为改变和极端气候加剧的预测，该研究结果强调了在评估扩大的未来气候风险时考虑eu jsl变率的重要性。
▲ abstract：
the jet stream is an important dynamic driver of climate variability in the northern hemisphere mid-latitudes. modern variability in the position of summer jet stream latitude in the north atlantic–european sector (eu jsl) promotes dipole patterns in air pressure, temperature, precipitation and drought between northwestern and southeastern europe. eu jsl variability and its impacts on regional climatic extremes and societal events are poorly understood, particularly before anthropogenic warming. based on three temperature-sensitive european tree-ring records, we develop a reconstruction of interannual summer eu jsl variability over the period 1300–2004 ce (r2 = 38.5%) and compare it to independent historical documented climatic and societal records, such as grape harvest, grain prices, plagues and human mortality. here we show contrasting summer climate extremes associated with eu jsl variability back to 1300 ceas well as biophysical, economic and human demographic impacts, including wildfires and epidemics. in light of projections for altered jet stream behaviour and intensified climate extremes, our findings underscore the importance of considering eu jsl variability when evaluating amplified future climate risk.
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